EP3947927B1 - Sliding sleeve cam system and engine - Google Patents

Description

The invention relates to a sliding cam system according to the preamble of claim 1. Furthermore, the invention relates to an engine with such a sliding cam system.

A sliding cam system of the type mentioned above is, for example, made of USS2010/ 236506 A1 and DE 10 2011 054 218 A1 known.

The known sliding cam system has a rotatably mounted camshaft. The camshaft comprises several sliding cams. The sliding cams are axially movable. The axial movement of the sliding cams is initiated by an actuator.

For this purpose, a coupling rod is firmly connected to a sliding cam via a shift fork, which is immediately moved axially by the actuator. When the sliding cam moves axially, the coupling rod moves with the sliding cam.

The coupling rod comprises guides. The guides are firmly connected to the coupling rod. The guides are each assigned to a further sliding cam. The further sliding cams have pins that interact with the respective guides in such a way that the further sliding cams are moved in accordance with the movement of the sliding cam that is firmly connected to the coupling rod.

The sliding cam system described above has the following disadvantages.

When designing and manufacturing engines, it is important that the available installation space is used efficiently. The coupling rod with guides requires a lot of space due to its design. Furthermore, the manufacturing effort and cost of such a coupling rod are comparatively high.

The invention is therefore based on the object of specifying a sliding cam system of the type mentioned at the beginning, by means of which installation space can be saved and that can be implemented with low production and cost expenditure. The invention is also based on the object of specifying an engine with such a sliding cam system.

• das Schiebenockensystem durch den Gegenstand des Anspruchs 1 oder den Gegenstand des Anspruchs 14 und
• den Motor durch den Gegenstand des Anspruchs 15
  gelöst.

According to the invention, this object is achieved with regard to

• the sliding cam system by the subject matter of claim 1 or the subject matter of claim 14 and
• the engine by the subject matter of claim 15
  solved.

Specifically, the object is achieved by a sliding cam system for an internal combustion engine with at least one camshaft comprising a carrier shaft with at least two sliding cam elements. The sliding cam elements each comprise a switching gate with at least one switching groove, wherein the sliding cam elements can be displaced axially to the carrier shaft by at least one actuator pin. At least one adjusting element is arranged parallel to a longitudinal axis of the carrier shaft, wherein the adjusting element can be displaced axially in the direction of the longitudinal axis of the carrier shaft. In other words, the adjusting element can be displaced axially along the longitudinal axis of the carrier shaft. The adjusting element has at least two coupling pins, wherein a first coupling pin is arranged in the region of the first sliding cam element and a second coupling pin is arranged in the region of the second sliding cam element. The coupling pins each interact with a switching gate of the respective associated sliding cam element in such a way that a movement of the first sliding cam element initiated by the actuator pin can be transferred to the second sliding cam element by the adjusting element.

The sliding cam system according to the invention allows the transmission of an axial movement of a conventionally switched sliding cam element to at least one further sliding cam element.

Conventionally switched means that the axial movement is initiated by an actuator, in particular by an actuator pin.

In order to move the first sliding cam element in an axial direction, the actuator pin engages in a first switching groove of the switching gate of the first sliding cam element. The actuator pin cannot be moved in the axial direction of the carrier shaft. The actuator pin is guided in sections in the switching groove and is limited by at least one flank of the switching groove. The sliding cam element can be moved in an axial direction due to the course of the switching groove. The actuator pin is only arranged in the switching groove during the displacement process.

The first coupling pin engages in a second switching groove. The first coupling pin is permanently arranged in the second switching groove. When the first sliding cam element is displaced, the first coupling pin interacts with the second switching groove in such a way that the axial movement of the sliding cam element is transferred to the adjustment element.

In one possible embodiment, the movement is transmitted to the adjustment element at different times due to the angular offset of the actuator pin. In another possible embodiment, the first sliding cam element comprises an annular groove into which the first coupling pin permanently engages, thus enabling the adjustment element to be moved at the same time.

The second coupling pin is arranged on the adjustment element offset from the first coupling pin in the axial direction of the carrier shaft. The second coupling pin interacts with a second sliding cam element. More precisely, the second coupling pin engages in a switching groove of the switching gate of the second sliding cam element. Due to the axial movement of the adjustment element, the second coupling pin is arranged on a flank of the switching groove of the second sliding cam element. The second coupling pin applies a force to the flank of the switching groove of the second sliding cam element, which moves the second sliding cam element axially in accordance with the movement of the first sliding cam element. It is conceivable that the adjustment element comprises several coupling pins that interact with further sliding cam elements.

The advantage of the sliding cam system according to the invention is that the adjustment element has a simple and space-saving design. Since the coupling pins of the adjustment element are inserted into the guides of the sliding cam elements engage, the adjusting element can be arranged closer to the carrier shaft, which means that less installation space is required by the camshaft.

Preferred embodiments of the invention are specified in the subclaims.

The adjustment element is arranged parallel to a longitudinal axis of the carrier shaft. This makes it easy to implement a movement in the axial direction of the carrier shaft. It is conceivable that the adjustment element is arranged on a rail for this purpose.

In a particularly preferred embodiment, the adjustment element comprises at least one receiving element and the carrier shaft comprises at least one locking element, which interact with one another during operation in such a way that the adjustment element is locked between two position changes. The advantage is that the adjustment element is locked in this way and the sliding cam element does not carry out any undesired movements, for example triggered by impacts or vibrations.

In a further embodiment, the locking element forms an abutment for the receiving element, so that the locking element is at least partially subjected to the forces acting during the change in position of the at least second sliding cam element.

For this purpose, a circular disk is arranged on the carrier shaft and extensions are arranged on the adjustment element. During operation, the circular disk is arranged between the extensions. The extensions limit the circular disk in the axial direction. The circular disk forms an abutment for the extensions of the adjustment element. In other words, the adjustment element is supported by an extension against the circular disk. The circular disk thus absorbs the switching forces of the second sliding cam element. The circular disk comprises a recess which is formed at an angle of rotation of the circular disk in such a way that when the adjustment element changes axially, the circular disk does not collide with any extension.

The adjustment element advantageously comprises a spring-ball lock. This additionally secures the adjustment element axially. This means that axial movement of the adjustment element in the area of the recess in the circular disk is only possible possible if the axial movement is initiated by the first sliding cam element.

In a preferred embodiment, the at least one actuator pin and the at least two coupling pins are offset in a circumferential direction of the carrier shaft, in particular offset by 90° in a circumferential direction of the carrier shaft. More precisely, the actuator pin and the coupling pin are offset from one another in the circumferential direction. This makes it possible to switch the sliding cam elements in an offset manner. Alternatively, other angular offsets, for example greater than 90° or less than 90°, are conceivable.

Particularly preferably, the switching gate of the first sliding cam element comprises a first switching groove and at least one second switching groove, wherein the first switching groove is provided for receiving the at least one actuator pin and the second switching groove is provided for receiving the first coupling pin.

The separate switching grooves advantageously enable a phase-shifted movement of the adjusting element or the sliding cam elements.

It is also particularly preferred that the first switching groove and the second switching groove have the same angle of rotation, with the radius of the first switching groove being larger than the radius of the second switching groove. This makes it possible to switch the sliding cam elements in an offset manner. Alternatively, other degrees of offset are conceivable.

It is advantageous if the first and second switching grooves of the first sliding cam element have a V-shaped profile at least in sections. By changing the groove width in the axial direction of the carrier shaft, a continuous displacement of the sliding cam element can be achieved. Other shapes, for example S-shaped, are conceivable.

Particularly advantageously, the first switching groove of the first sliding cam element has a Y-shaped profile at least in sections. This makes it possible for the first sliding cam element to comprise a second switching groove for the first coupling pin, which is arranged in such a way that the second sliding cam can be moved directly.

Particularly preferably, the second switching groove for the first coupling pin is arranged at least partially centrally in the Y-shaped first switching groove. This enables a direct displacement of the second sliding cam element.

The second switching groove is also advantageously designed as a groove extending over the circumference with a constant radius, in which the first coupling pin is permanently arranged such that an axial displacement of the first sliding cam element can be transferred directly to the adjustment element. More precisely, it is thus possible for a time-delayed or phase-shifted axial movement of the at least second sliding cam element to depend only on the switching gate of the at least second sliding cam element.

In a further preferred embodiment, the first switching groove of the first sliding cam element has areas with different radii, which are each assigned to an area of the first sliding cam element, in particular an entry area, a displacement area and an ejection area. This results in a smooth retraction and extension of the actuator pin and an essentially continuous displacement of the first sliding cam element.

It is advantageous if the switching gate of the second sliding cam element has a V-shaped profile at least in sections. The V-shaped profile is easy to implement, for example by milling.

The carrier shaft advantageously comprises at least a third, in particular at least a fourth, sliding cam element. This means that the sliding cam system can be used in larger internal combustion engines. It is conceivable that the sliding cam system comprises several camshafts.

In a preferred embodiment, the sliding cam elements are designed as double sliding cam elements, wherein each of the double sliding cam elements is designed to control valves of two cylinders.

On the respective sliding cam elements, valve cams, in particular cam sections with one or more cam contours, of a single cylinder as well as valve cams, in particular cam sections with one or several cam contours, from several adjacent cylinders. The valve cams of the respective sliding cam element can have different valve lifts.

For example, double sliding cam elements can be used that include valve cams from two adjacent cylinders. In other words, the double sliding cam elements can be designed to actuate valves from two adjacent, in particular separate, cylinders. In this case, the camshaft can have exactly two double sliding cam elements, with each double sliding cam element controlling at least one valve from two adjacent cylinders during operation. Such camshafts can be used in four-cylinder variants of internal combustion engines.

Alternatively, the sliding cam elements can be designed to control at least one valve of a single cylinder. In this case, the camshaft can have exactly three sliding cam elements. Such camshafts can be used in three-cylinder variants of internal combustion engines.

In general, valve cams for associated intake valves and/or associated exhaust valves can be arranged on the respective sliding cam elements or double sliding cam elements or just on one of the sliding cam elements or double sliding cam elements. The combination of valve cams for associated intake valves and associated exhaust valves on the sliding cam element(s) or double sliding cam elements can be used for internal combustion engines with only one camshaft. This camshaft can be used, for example, as a single overhead camshaft (SOHC) in internal combustion engines.

In a preferred embodiment, the switching grooves of the first and second sliding cam elements are arranged offset from one another at an angle of rotation such that the second sliding cam element can be displaced along a longitudinal direction of the carrier shaft at a time offset from the first sliding cam element.

The time-delayed displacement of the sliding cam element enables a time-delayed activation and/or deactivation of the valves of a cylinder of an internal combustion engine.

In a further embodiment, the second and the third sliding cam element each have a V-shaped profile at least in sections, wherein the V-shaped profiles each have a constant radius.

The V-shaped profiles with constant radius are advantageous because no entry or ejection path is necessary in the second and third sliding cam elements.

Particularly preferably, the switching grooves of the first, second and third sliding cam elements are arranged offset from one another at an angle of rotation such that the second and third sliding cam elements can each be displaced at a time offset from the first sliding cam element along a longitudinal direction of the carrier shaft.

This makes it possible to activate and/or deactivate the valves of a cylinder, or in particular of several cylinders, at different times.

In a preferred embodiment, the sliding cam elements each have at least one cam section for controlling a valve of a cylinder, wherein at least one lifting cam contour for actuating the valve is formed in the cam section. The sliding cam elements each preferably have at least two cam sections for controlling valves of only one cylinder, wherein at least one lifting cam contour for actuating the respective valve is formed in the cam sections. In other words, the sliding cam elements can each switch valves of only one cylinder. The cam sections of the sliding cam elements are thus assigned to only one cylinder.

This advantageously enables the sliding cam elements to be designed in several different variants. For example, the cam section can have several cam contours, preferably with different strokes, so that the associated valve can be actuated in several switching stages, i.e. with different strokes.

In a preferred embodiment, the sliding cam elements, in particular double sliding cam elements, each have at least two cam sections for controlling valves of two adjacent cylinders.

At least one lifting cam contour is formed in each of the two cam sections for actuating the valve of one of the two adjacent cylinders. The sliding cam elements, in particular double sliding cam elements, preferably each have at least four cam sections for controlling valves of two adjacent cylinders, with at least one lifting cam contour being formed in the cam sections for actuating the respective valve. In other words, the sliding cam elements, in particular double sliding cam elements, can each switch valves of two cylinders. The cam sections of the sliding cam elements, in particular double sliding cam elements, are each assigned to two cylinders.

Advantageously, double sliding cam elements with more than one cam section are made possible here, which can have several cam contours, preferably with different strokes. This makes it possible to actuate the respective valves in several switching stages, i.e. with different strokes.

In general, the respective cam section is used to control an associated valve of a cylinder. In other words, the associated valve can be actuated by the cam section, i.e. a stroke can be transferred to it, or the associated valve can not be actuated and the cylinder can therefore be switched off.

The respective cam section preferably has at least two lifting cam contours, in particular at least three lifting cam contours, for actuating the valve, wherein the lifting cam contours each comprise different strokes. This allows the associated valve to be operated in two switching stages. In other words, when the sliding cam element is axially displaced, the associated valve can be actuated with two different strokes. In a further variant, the respective cam section can have at least three lifting cam contours with different strokes. This allows the associated valve to be operated in a total of three switching stages. When the sliding cam element is axially displaced, the associated valve can thus be actuated with three different strokes. The described multi-stage control of a valve of a cylinder enables increased variability in the control of the valve and thus of the internal combustion engine. For example, this allows the change between different operating modes of the internal combustion engine, e.g. full load operation, partial load operation.

Further preferably, the cam section additionally has at least one zero-lift cam contour for switching off the cylinder assigned to the valve, wherein the zero-lift cam contour is adjacent to a/the lifting cam contour. The cam section can have a lifting cam contour and an adjacent zero-lift cam contour. When the sliding cam element is axially displaced, it is possible to switch between the lifting cam contour or the zero-lift cam contour. This corresponds to a two-stage control of the valve. Alternatively, the cam section can have two lifting cam contours with different strokes and an adjacent zero-lift cam contour. When the sliding cam element is axially displaced, it is possible to switch between the two lifting cam contours or between one of the two lifting contours and the zero-lift cam contour. This corresponds to a three-stage control of the valve. Other combinations of several lifting cam contours and at least one zero-lift cam contour are possible.

Within the scope of the invention, the lifting cam contour corresponds to a contour that causes a lift of the associated valve during operation. The lifting cam contour is part of a lifting cam. The zero-lift cam contour does not cause a lift of the associated valve. The zero-lift cam contour is part of a zero-lift cam. The zero-lift cam contour is preferably circular, in particular cylindrical. The zero-lift cam contour is advantageously used for cylinder deactivation.

In one embodiment, at least one multiple actuator with at least two actuator pins, in particular at least three actuator pins, is provided, by means of which the sliding cam elements can be brought into at least two, in particular three, axial positions in order to enable different switching positions, in particular for two-stage, three-stage or multi-stage control, for the valves. The two actuator pins of the multiple actuator enable the sliding cam elements coupled to one another by the adjustment element to be moved between a total of two axial positions. In this embodiment, the at least one cam section of the respective sliding cam element preferably has a lifting cam contour and a zero-lift cam contour or two lifting cam contours with different strokes. By combining the multiple actuator with two actuator pins and The cam section has two contours, enabling two-stage control of the valve assigned to the cam section.

In a variant with three actuator pins of the multiple actuator, the sliding cam elements coupled to one another by the adjustment element can be moved between a total of three axial positions. In this embodiment, the at least one cam section of the respective sliding cam element preferably has two lifting cam contours with different strokes and one zero-lift cam contour or a total of three lifting cam contours with different strokes. The combination of the multiple actuator with three actuator pins and the cam section with a total of three contours enables three-stage control of the valve assigned to the cam section.

In a further embodiment, the first sliding cam element and the multiple actuator are arranged in a first axial region of the carrier shaft and the second and/or third sliding cam element is/are arranged in a second axial region of the carrier shaft adjacent to the first axial region. In a further embodiment, the first sliding cam element and the multiple actuator are arranged in the longitudinal direction of the carrier shaft between the second and the third sliding cam element, in particular in the middle, and the second and/or third sliding cam element is/are arranged in a second axial region of the carrier shaft adjacent to the first axial region. By arranging the sliding cam elements and the multiple actuator differently, the sliding cam system can be variably adapted to the existing installation space situation and the tolerance position.

In a further preferred embodiment, the locking element has at least in sections a circular disk or an annular disk, wherein the locking element is arranged between the first and the second sliding cam element or between the second and the third sliding cam element. Alternatively, the locking element can be arranged between an axle end of the carrier shaft and one of the sliding cam elements. The axle end is the longitudinal end of the carrier shaft. When the camshaft is designed with two double sliding cam elements, the locking element can be arranged between the two double cam elements or between an axle end or longitudinal end of the carrier shaft and a of the double cam elements. A design of the camshaft with more than two double sliding cam elements is possible.

The circular disk or the ring disk are advantageous because they each have a flat surface that is suitable as an abutment in an axial direction of the carrier shaft.

In a further preferred embodiment, the locking element is formed integrally with the carrier shaft. Preferably, the locking element is formed by at least one recess in the carrier shaft. The recess can be formed by at least two circumferential grooves and at least one longitudinal passage connecting the grooves. The grooves can be formed radially circumferentially in the carrier shaft. During operation, the receiving element is arranged in one of the two grooves, at least partially depending on the axial position of the sliding cam elements. If the axial position of the sliding cam elements and thus of the adjustment element is changed during operation during a displacement process, the receiving element moves through the longitudinal passage and changes from the first to the second circumferential groove. The receiving element is supported against the groove walls in order to transfer the forces occurring during the axial displacement to the carrier shaft. This design of the recess is used in a two-stage control of the valves, in particular by two contours of the respective cam sections.

With a three-stage control of the valves, in particular by three contours of the respective cam sections, the recess can be formed by a total of three circumferential grooves and two longitudinal passages. In this case, one longitudinal passage connects two grooves, so that a total of three axial positions are possible when the sliding cam elements are moved axially. The power transmission from the receiving element to the carrier shaft can take place as described above.

Within the scope of the invention, the receiving element is suitable for receiving the locking element, in particular the circular disk or the annular disk, and for being received by the locking element, in particular the recess of the carrier shaft.

The integral design of the locking element has the advantage that a locking element as a separate component can be omitted. The locking element is replaced by the recess in the carrier shaft. This simplifies the structure of the sliding cam system and saves costs.

In a further embodiment, at least one camshaft bearing, in particular a roller bearing and/or a plain bearing, is provided. A part of the camshaft bearing forms the locking element. This embodiment also has the advantage that components are reduced and costs are therefore saved.

In a preferred embodiment, the carrier shaft has at least two locking elements. Furthermore, the receiving element of the adjusting element preferably forms at least one extension which interacts with one or both locking elements during operation, so that at least one of the two locking elements can be at least partially subjected to the forces acting when the second and/or third sliding cam element changes position. During operation, the locking element can be arranged on one of the two locking elements or between the two locking elements, depending on the axial position of the sliding cam elements. The locking elements limit the extension in the axial direction. The locking elements each form an abutment for the extension of the adjusting element. During operation, the adjusting element with extension is supported against one of the two locking elements. The locking element thus absorbs the switching forces of the second or third sliding cam element. The locking element comprises a recess which is formed at an angle of rotation of the locking element in such a way that the locking element does not collide with the extension when the adjusting element changes axially.

In a further preferred embodiment, the carrier shaft has at least one locking element. Furthermore, the receiving element of the adjustment element preferably forms at least two extensions, which interact with the locking element during operation, so that the locking element can be at least partially subjected to the forces acting when the second and/or third sliding cam element changes position. The locking element can be arranged on one of the two extensions during operation, depending on the axial position of the sliding cam elements, or can be arranged between the two extensions. The extensions limit the locking element in the axial direction. The locking element forms an abutment for the extensions of the adjustment element. In other words, the adjustment element is supported against the locking element with one of the two extensions or both extensions. The The locking element thus absorbs the switching forces of the second or third sliding cam element. The locking element comprises a recess which is formed at a rotation angle of the locking element in such a way that when the adjustment element changes axially, the locking element does not collide with any extension.

The various combinations of extensions and locking elements of the two aforementioned designs make it possible to absorb the adjustment forces that occur for a three-stage control of valves. The adjustment forces are transferred from the respective receiving element to the respective locking element at all three axial positions, thus relieving the load on the system.

In a further particularly preferred embodiment, a stop is formed in a cylinder head, in particular in a cylinder cover, and the adjusting element has a stop element which cooperates with the stop in the cylinder head such that the axial displacement of the adjusting element is limited.

This defines the starting point and the end point of the axial displacement of the adjustment element. Furthermore, the stop and the stop element prevent unwanted movements of the adjustment element.

In a preferred embodiment, the receiving element is the stop element, whereby during operation the receiving element together with the stop of the cylinder head limits the axial displacement of the adjustment element. In this case, the stop and receiving element form a single element. This reduces the number of components and the effort involved in manufacturing. This saves costs.

In a further preferred embodiment, the adjusting element has at least one stop end in the direction of displacement, which interacts with a counterpart, in particular the cylinder head, during operation in such a way that the axial displacement of the adjusting element is limited. The stop end can be formed by a longitudinal end of the adjusting element. The adjusting element preferably has two longitudinal ends and thus two stop ends, which limit a displacement path along the longitudinal axis of the carrier shaft. For this purpose the longitudinal ends can interact with stop areas of the cylinder head cover.

This also has the advantage that the starting point and the end point of the axial displacement of the adjustment element are fixed. Furthermore, this reduces the number of components, since the longitudinal ends of the adjustment element limit the axial displacement path instead of a separate stop element.

It is advantageous if the locking element is arranged on the carrier shaft in a rotationally fixed manner and is displaceable along a longitudinal direction of the carrier shaft, wherein the locking element is guided axially in the cylinder head, in particular in the cylinder head cover.

By guiding or supporting the locking element in the cylinder head, it is possible for all axial positions to be specified by the cylinder head. This is advantageous for determining the manufacturing tolerances.

The bearing can be designed as one piece or two pieces with the cylinder head. A one-piece design with the cylinder head enables cost-effective and easy production. This also saves installation space and weight.

The two-part design enables the use of various high-strength materials. This makes it possible to absorb greater forces and reduce wear. The bearings can also be replaced if necessary. Furthermore, the influence of different thermal expansions on different materials can be kept small. For example, the cylinder cover can be made of aluminum and the support shaft of steel. The play in the switching gates, the cam widths and thus the displacement paths can be kept small in this way. Overall, the dynamic switching forces that occur in the camshaft can be better controlled.

In a further embodiment, the locking element is arranged on the carrier shaft in a rotationally fixed manner and is fixed in the longitudinal direction of the carrier shaft.

The locking element, which is arranged on the carrier shaft in a rotationally fixed manner and fixed in the longitudinal direction, is advantageous in terms of manufacturing tolerances, since almost all axial positions are predetermined by the camshaft. Furthermore, the thermal expansion only affects the groove width of the primary cam. The play in the shift gates, the cam widths and thus the displacement paths can be kept small, which makes the dynamic shifting forces easier to control.

If the locking element is arranged on the support shaft in a rotationally fixed and longitudinally fixed manner, the spring-ball locking of the adjusting element can preferably have the function of the stop.

This means that the stop in the cylinder head and the stop element can be eliminated.

Further preferably, the adjusting element is arranged offset at a rotation angle to the at least one actuator pin.

It is particularly advantageous if the second switching groove is arranged at an axial end of the first sliding cam element next to the first switching groove or the second switching groove is arranged between two axial ends of the first sliding cam element, wherein the second switching groove extends substantially over the entire circumference of the first sliding cam element.

The arrangement of the adjustment element offset by an angle of rotation and the above-described arrangement of the second switching groove on the first sliding cam element is advantageous because the adjustment element does not obstruct the actuator pins and vice versa.

In one embodiment, the first switching groove of the first sliding cam element is at least partially Y-shaped or at least partially S-shaped.

According to the independent claim 14, the invention relates to a sliding cam system for an internal combustion engine with at least one camshaft comprising a carrier shaft with at least two double sliding cam elements, each of which is designed to control valves of two cylinders, wherein the double sliding cam elements each comprise a switching gate with at least one switching groove and at least one cam section with at least one lifting cam contour. The double sliding cam elements are connected axially to the Carrier shaft displaceable. Furthermore, at least one adjustment element is arranged parallel to a longitudinal axis of the carrier shaft, which is axially displaceable in the direction of the longitudinal axis of the carrier shaft. The adjustment element has at least two coupling pins, wherein a first coupling pin 17a' is arranged in the region of the first double sliding cam element and a second coupling pin is arranged in the region of the second double sliding cam element. The coupling pins each interact with a switching gate of the respective associated double sliding cam element in such a way that a movement of the first double sliding cam element initiated by the actuator pin can be transferred to the second double sliding cam element by the adjustment element.

Reference is made here to the advantages explained in connection with the sliding cam system according to claim 1. Furthermore, the sliding cam system according to claim 14 can alternatively or additionally have individual features or a combination of several features previously mentioned in relation to the sliding cam system according to claim 1.

Within the scope of the invention, an engine with at least one such sliding cam system is also disclosed and claimed. It is possible for the engine to have several, in particular at least two, sliding cam systems according to the invention. In particular, the engine can have six cylinders arranged in series. Two of the aforementioned sliding cam systems can be used here. The two sliding cam systems of the six-cylinder engine can have a common carrier shaft on which the sliding cam elements of the two sliding cam systems are arranged so as to be axially displaceable. Preferably, at least two actuators, in particular multiple actuators, are used for the axial adjustment of the sliding cam elements, with one actuator preferably axially displacing the sliding cam elements of one of the two sliding cam systems during operation. The invention is explained in more detail below using exemplary embodiments with reference to the accompanying drawings.

Fig. 1

eine perspektivische Ansicht eines erfindungsgemäßen Ausführungsbeispiels eines Schiebenockensystems;

Fig. 2

eine weitere perspektivische Ansicht eines erfindungsgemäßen Ausführungsbeispiels eines Schiebenockensystems;

Fig. 3

eine Seitenansicht eines erfindungsgemäßen Ausführungsbeispiels eines Schiebenockensystems;

Fig. 4

eine weitere Seitenansicht eines erfindungsgemäßen Ausführungsbeispiels eines Schiebenockensystems;

Fig. 5

eine perspektivische Ansicht eines weiteren erfindungsgemäßen Ausführungsbeispiels eines Schiebenockensystems;

Fig. 6

eine Seitenansicht eines erfindungsgemäßen Ausführungsbeispiels eines Schiebenockensystems in einem Zylinderkopf;

Fig. 7

eine weitere Seitenansicht des Schiebenockensystems gemäß Fig. 6;

Fig. 8

eine Seitenansicht eines weiteren erfindungsgemäßen Ausführungsbeispiels eines Schiebenockensystems;

Fig. 9

eine weitere Seitenansicht des Schiebenockensystems gemäß Fig. 8;

Fig. 10

eine Seitenansicht eines erfindungsgemäßen Ausführungsbeispiels eines Schiebenockensystems in einem Zylinderkopf;

Fig. 11

eine perspektivische Ansicht eines weiteren erfindungsgemäßen Ausführungsbeispiels eines Schiebenockensystems;

Fig. 12

eine Seitenansicht des Schiebenockensystems gemäß Fig. 11;

Fig. 13

eine perspektivische Ansicht eines weiteren erfindungsgemäßen Ausführungsbeispiels eines Schiebenockensystems;

Fig. 14

eine Seitenansicht des Schiebenockensystems gemäß Fig. 13;

Fig. 15

eine perspektivische Ansicht eines weiteren erfindungsgemäßen Ausführungsbeispiels eines Schiebenockensystems;

Fig. 16

eine Seitenansicht des Schiebenockensystems gemäß Fig. 15;

Fig. 17

eine schematische Darstellung einer Trägerwelle eines weiteren erfindungsgemäßen Ausführungsbeispiels eines Schiebenockensystems;

Fig. 18

eine schematische Darstellung einer Trägerwelle mit Arretierelement und eines Verstellelements eines weiteren erfindungsgemäßen Ausführungsbeispiels eines Schiebenockensystems.

Showing:

Fig. 1

a perspective view of an embodiment of a sliding cam system according to the invention;

Fig. 2

a further perspective view of an embodiment of a sliding cam system according to the invention;

Fig. 3

a side view of an embodiment of a sliding cam system according to the invention;

Fig. 4

a further side view of an embodiment of a sliding cam system according to the invention;

Fig. 5

a perspective view of another embodiment of a sliding cam system according to the invention;

Fig. 6

a side view of an embodiment of a sliding cam system in a cylinder head according to the invention;

Fig. 7

another side view of the sliding cam system according to Fig. 6 ;

Fig. 8

a side view of another embodiment of a sliding cam system according to the invention;

Fig. 9

another side view of the sliding cam system according to Fig. 8 ;

Fig. 10

a side view of an embodiment of a sliding cam system in a cylinder head according to the invention;

Fig. 11

a perspective view of another embodiment of a sliding cam system according to the invention;

Fig. 12

a side view of the sliding cam system according to Fig. 11 ;

Fig. 13

a perspective view of another embodiment of a sliding cam system according to the invention;

Fig. 14

a side view of the sliding cam system according to Fig. 13 ;

Fig. 15

a perspective view of another embodiment of a sliding cam system according to the invention;

Fig. 16

a side view of the sliding cam system according to Fig. 15 ;

Fig. 17

a schematic representation of a carrier shaft of another embodiment of a sliding cam system according to the invention;

Fig. 18

a schematic representation of a carrier shaft with locking element and an adjusting element of a further embodiment of a sliding cam system according to the invention.

The Figures 1 to 4 show the same embodiment of a sliding cam system from different perspectives.

The sliding cam system comprises a carrier shaft 11. A first and a second sliding cam element 12a, 12b are arranged on the carrier shaft 11 so as to be axially movable relative to a longitudinal axis of the carrier shaft 11. It is conceivable that more than two sliding cam elements are arranged on the carrier shaft 11. The carrier shaft 11 comprises three roller bearings 20. One roller bearing 20 is arranged at each of the axial ends of the carrier shaft 11 and another roller bearing 20 is arranged between the sliding cam elements 12a, 12b. The roller bearings 20 are locked in place by retaining rings 21. The number of roller bearings 20 and retaining rings 21 as well as the positions of the bearing points are variable. The sliding cam elements 12a, 12b comprise a switching gate 13 and a cam contour 22.

The switching gate 13 of the first sliding cam element 12a comprises a first and a second switching groove 14a, 14b. The switching grooves 14a, 14b are V-shaped at least in sections. In other words, the width of the two switching grooves 14a, 14b is not constant. The width is to be understood as the distance between the flanks of the switching grooves 14a, 14b in the axial direction to the carrier shaft 11. The flanks of the switching grooves 14a, 14b approach one another in the V-shaped section.

The two switching grooves 14a, 14b are arranged at the same angle of rotation. The first switching groove 14a has a larger radius than the second switching groove 14b.

The term radius is understood to mean the distance between the groove base surface of the first or second switching groove 14a, 14b and the central longitudinal axis of the carrier shaft 11. Thus, the outer diameter of the switching gate 13 and the radius of the groove base surface determine the groove depth.

The first switching groove 14a comprises a step. In other words, the first switching groove 14a is designed as a projection or a step. The first switching groove 14a has a varying radius. This means that the first switching groove 14a has sections with a larger radius and a smaller radius. The radius is changed continuously. The areas are each assigned to an entry area, an extension area or a displacement area.

The second switching groove 14b has a constant radius. The width of the second switching groove 14b is smaller than the width of the first switching groove 14a.

Two actuator pins 15 are arranged on the carrier shaft 11. The actuator pins 15 are essentially only movable in a direction orthogonal to the central longitudinal axis of the carrier shaft 11. The actuator pins 15 are assigned to the first switching groove 14a. This means that the actuator pins only interact with the first switching groove 14a. The actuator pins 15 are spaced apart from one another in the axial direction of the carrier shaft 11. As a result, depending on the position of the first sliding cam element, one of the two actuator pins 15 can be inserted into the first switching groove 14a. By inserting the actuator pins 15, an axial movement of the first sliding cam element 14a can be initiated.

For this purpose, an actuator pin 15 is inserted into the first switching groove 14a. By reducing the width of the groove, the inserted actuator pin 15 interacts with a flank of the first switching groove 14a. More precisely, the inserted actuator pin 15 applies a force to a flank of the first switching groove 14a that is directed opposite to the flank. This causes the axial displacement of the first sliding cam element 12a. The direction of the displacement therefore depends on the flank with which the inserted actuator pin 15 interacts. An actuator pin 15 is assigned to each flank of the first switching groove 14a.

An adjusting element 16 is arranged parallel to the carrier shaft 11. The adjusting element 16 is axially movable. The adjusting element is offset by 90° to the actuator pins 15. Alternatively, other angular offsets are conceivable. The adjusting element 16 comprises a first and a second coupling pin 17a, 17b and a receiving element 18. The first and second coupling pins 17a, 17b are each arranged at an axial end of the adjustment element 16. The receiving element 18 comprises three extensions and is arranged between the axial ends of the adjustment element 16. The coupling pins 17a, 17b and the receiving element 18 extend orthogonally to the central longitudinal axis of the carrier shaft 11.

The first coupling pin 17a is associated with the second switching groove 14b of the first sliding cam element 12a. The first and second coupling pins 17a, 17b are arranged essentially rotatably on the adjustment element 16. The first coupling pin 17a is permanently in engagement with the second switching groove 14b of the first sliding cam element 12a.

The first coupling pin 17a is subjected to a force by a flank of the second switching groove 14b. The adjustment element 16 is displaced in the direction of action of the force. Since the adjustment element 16 and thus the coupling pins 17a, 17b are offset from one another by 90° in the circumferential direction and the first and second switching grooves 14a, 14b are arranged at the same angle of rotation, the displacement of the adjustment element 16 takes place with a corresponding time offset or phase shift.

The second coupling pin 17b is arranged in the area of the second sliding cam element 12b. The second sliding cam element 12b comprises a switching groove 14. The switching groove 14 has a V-shaped section. The second coupling pin 17b is permanently engaged with the switching groove 14. The switching groove 14 of the second sliding cam element 12b is arranged in such a way that the second sliding cam element 12b can be switched at a different time than the first sliding cam element 12a.

By moving the adjustment element 16, the second coupling pin 17b is moved axially in the switching groove 14. More precisely, the second coupling pin 17b is moved to one of the flanks of the switching groove 14. The second coupling pin 17b interacts with the switching groove 14 in essentially the same way as the actuator pins 15 interact with the first switching groove 14a of the first sliding cam element 12a.

The carrier shaft 11 comprises a circular disk-shaped locking element 19. Alternatively, other geometries are conceivable. The locking element 19 is between the first and the second sliding cam element 12a, 12b. The locking element 19 is axially limited by the receiving element 18. The locking element 19 has a supporting function. The locking element 19 forms an abutment for the receiving element 18. The locking element 19 absorbs the forces during the switching process and thus enables the adjustment element 16 to be fixed. Furthermore, the interaction of the receiving element 18 and the locking element 19 prevents the first sliding cam element 12a from being moved unintentionally. The receiving element 18 comprises two receptacles for the locking element 19. The locking element 19 comprises a recess. This makes it possible to move the adjustment element through the circular disk. For this purpose, the recess is arranged in the area of the corresponding angle of rotation. The recess is arranged in the circular disk in such a way that the adjusting element 16 is moved through the recess during an axial movement. It is conceivable that the adjusting element 16 additionally comprises a spring-ball locking mechanism (not shown).

In summary, the previously described

Sliding cam system by means of the adjusting element 16 enables phase-shifted switching of the sliding cam elements 12a, 12b using a single actuator. This allows the total number of actuators in the sliding cam system to be significantly reduced.

Fig. 5 describes a further embodiment of a sliding cam system. The sliding cam system essentially corresponds to the sliding cam system according to the Figures 1 to 4 . In contrast to the system described above, the sliding cam system shown comprises a third sliding cam element 12c and the first sliding cam element 12a has a differently shaped switching gate.

As in the embodiment above, the support shaft 11 comprises rolling bearings 20 and retaining rings 21. The rolling bearings 20 and retaining rings 21 are arranged at the axial ends of the support shaft 11 and between the sliding cam elements 12a, 12b, 12c.

The adjustment element 16 is arranged parallel to the carrier shaft 11. The adjustment element 16 is guided in a rail and offset by 45° to 60° in the circumferential direction to the actuator pins. The offset can alternatively for example, 90°. The adjustment element 16 comprises a third coupling pin 17c, which is arranged in the region of the third sliding cam element 12c.

An actuator 23 with the actuator pins 15 is arranged in the area of the first sliding cam element 12a. The first sliding cam element 12a has a Y-shaped first switching groove 14a.

The second switching groove 14b is designed as a groove extending over the entire circumference of the first sliding cam element 12a, in particular as an annular groove. The radius of the second switching groove 14b is smaller than the radius of the first switching groove 14a. The first and second switching grooves 14a, 14b therefore have different angles of rotation.

The first coupling pin 17a is permanently engaged with the second switching groove 14b as in the embodiment described above.

The continuous second switching groove 14b enables an immediate displacement of the adjusting element 16 without any time delay, i.e. the adjusting element 16 and the first sliding cam element 12a move essentially simultaneously.

The switching grooves 14 of the second and third sliding cam elements 12b, 12c are arranged on the outer peripheral surface in such a way that the sliding cam elements 12b, 12c can be switched with a time delay. The second and third coupling pins 17b, 17c act as for the Figures 1 to 4 already described with the switching grooves 14 in a known manner.

A locking element 19 is arranged between the second and third sliding cam elements 12b, 12c. The locking element 19 comprises a circular disk with a recess. An extension is arranged on the adjustment element 16 in the area of the circular disk. The circular disk forms a support for the extension. The circular disk works together with the extension during a displacement process in such a way that the first coupling pin is relieved during the displacement process. In other words, the extension is supported against the circular disk. The recess is arranged at the angle of rotation at which the displacement of the first adjustment element 16 takes place.

In Fig. 6 another embodiment of a sliding cam system is shown. The sliding cam system is arranged in a cylinder head 25.

The sliding cam system comprises three sliding cam elements 12a, 12b, 12c. In Fig. 5 the cam contours 22 enclose the switching groove 14. In Fig. 6 the cam contours 22 of the sliding cam elements 12a, 12b, 12c are arranged exclusively on one side in the axial direction next to the switching groove 14. The switching groove 14 will be discussed in more detail later.

The sliding cam elements 12a, 12b, 12c each have two cam sections 29, in each of which two cam contours 22 are formed. A first cam section 29a borders on the switching gate 13 of the sliding cam element 12a, 12b, 12c. A second cam section 29b is arranged at a distance from the first cam section 29a in the axial direction. The cam sections 29a, 29b of the respective sliding cam element 12a, 12b, 12c are of the same design. Alternatively, it is possible for the cam sections 29a, 29b of the respective sliding cam element 12a, 12b, 12c to differ from one another.

The total of two cam contours 22 per cam section 29 form a lifting cam contour 31, a defined lift and a zero lift cam contour 32. This also applies to the cam contours 22 according to the Fig. 1 to 4 The two cam contours 31, 32 are arranged adjacent to each other in the axial direction.

It is also possible that the respective cam sections 29 do not have a zero-lift cam contour 32, i.e. instead of the zero-lift cam contour 32 they have another lifting cam contour 31. The three lifting cam contours 31 can have different strokes.

By designing the cam sections 29 with two different cam contours 22, the valve of a cylinder assigned to the respective cam section 29 can be controlled in two different switching positions during operation. Specifically, a defined stroke can be transferred to the valve during operation by the lifting cam contour 31 and the valve can thus be actuated. In addition, the cylinder assigned to the valve can be switched off during operation by the zero-lift cam contour 32. This is referred to as a two-stage control of the cylinder's valve.

The first sliding cam element 12a comprises the first switching groove 14a and the second switching groove 14b. The first switching groove 14a has a Y-shaped switching gate 13. The second switching groove 14b extends along a circumferential direction of the first sliding cam element 12a.

The switching grooves 14 of the second and third sliding cam elements 12b, 12c are V-shaped.

The locking element 19 is arranged between the second and the third sliding cam element 12b, 12c. The locking element 19 has a circular disk or an annular disk. The locking element 19 is arranged on the support shaft 11 in a rotationally fixed manner. The circular disk or the annular disk has a recess, as described in the previous embodiments. The recess extends along a circumferential direction of the circular disk or the annular disk.

The cylinder head 25 comprises an axial bearing in which the circular disk or the annular disk of the locking element 19 is guided and/or mounted.

The adjustment element 16 is arranged offset to the actuator pins 15 at an angle of rotation about the longitudinal axis of the carrier shaft 11. Coupling pins 17a, 17b, 17c are arranged on the adjustment element 16 offset in the axial direction. The first coupling pin 17a engages in the second switching groove 14b of the first sliding cam element 12a. The second coupling pin 17b engages in the switching groove 14 of the second sliding cam element 12b and the third coupling pin 17c engages in the switching groove 14 of the third sliding cam element 12c.

A spring-ball locking device 24 is arranged between the first and the second coupling pin 17a, 17b. Instead of the ball, other shapes are possible.

The adjustment element 16 has a stop element 27. The stop element 27 is designed as an extension that extends in a direction orthogonal to a longitudinal direction of the adjustment element 16. Other shapes are possible. The stop element 27 is arranged between the first coupling pin 17a and the second coupling pin 17b. More precisely, the stop element 27 is arranged between the recesses or notches for the spring-ball lock 14 and the first coupling pin 17a.

The receiving element 18 is arranged between the second and the third coupling pin 17b, 17c. The receiving element 18 has a single extension that extends in the direction of the camshaft 10.

A stop 26 is arranged in the cylinder head 25. The stop 26 is designed as a recess in the cylinder head 25. The stop element 27 projects into the recess.

In Fig. 7 is the embodiment according to Fig. 6 shown without the cylinder head 25.

In Fig. 7 the axial bearing 28 for the locking element 19 is clearly visible. The axial bearing 28 is designed as a single part. The axial bearing has a connecting section that is connected to the cylinder head 25. Alternatively, the axial bearing can be designed as one piece with the cylinder head 25. The axial bearing 28 includes a through gap.

The in Fig. 8 and Fig. 9 The embodiments shown correspond essentially to the embodiment according to Fig. 6 and Fig. 7 .

In contrast to the Fig. 6 and 7 In the embodiments shown, the cylinder head 25 in Fig. 8 and 9 no axial bearing 28 for the locking element 19. The locking element 19 is arranged on the carrier shaft 11 in a rotationally fixed manner and fixed in the axial direction.

In Fig. 10 is a combination of the Figures 6 to 9 illustrated embodiment, in which a stop 26 is arranged in the cylinder head and the locking element 19 is fixed in a rotationally fixed manner and in the axial direction on the carrier shaft 11.

The attack 26 in Fig. 10 is not absolutely necessary. Alternatively, the stop 26 can be omitted. The freedom of movement of the adjustment element 16 is then limited by the spring-ball lock 24.

The first switching groove 14a of the first sliding cam element 12a serves to receive the actuator pins 15. The second switching groove 14b serves to receive the first coupling pin 17a.

When the adjustment element 16 is displaced, the receiving element 18 and the locking element 19 work together in such a way that the receiving element 18 moves through the recess in the circular disk. In other words, the recess in the circular disk is arranged at an angle of rotation to the longitudinal axis of the support shaft 11 such that the receiving element 18 changes from one side of the circular disk to the other when the first sliding cam element 12a is displaced. During the displacement of the second and/or the third sliding cam element 12b, 12c, the receiving element 18 is supported against the uninterrupted area of the circular disk. The circular disk or the ring disk can be subjected to the forces acting when the second and the third sliding cam element 12b, 12c are displaced. The locking element 19 with the circular disk forms an abutment for the extension of the adjustment element 16.

The locking element 19 enables two defined positions of the adjustment element 16.

The stop 26 and the stop element 27 limit the axial freedom of movement of the adjusting element 16.

The spring-ball locking mechanism 24 of the adjustment element 16 prevents unwanted movements of the adjustment element 16. This improves operational reliability. It is also possible for the spring-ball locking mechanism 24 to take over the function of the stop 26 and the stop element 27. This is particularly advantageous if the locking element 19 is fixed on the carrier shaft in the axial direction.

The linear guide of the adjusting element 16 is formed in the cylinder head 25. This enables active oiling of the adjusting element 16.

The Fig. 11 and 12 and 13 and 14 show two further embodiments of a sliding cam system. The sliding cam system according to the Fig. 11 to 14 essentially correspond to the sliding cam system according to the Fig. 9 and 10 In contrast to the sliding cam system according to the Fig. 9 and 10 There is no extension formed as a stop element 27 on the adjusting element 16. However, it is possible that the adjusting element 16 has a stop element 27, as in Fig. 6 described.

Furthermore, the two sliding cam systems according to the Fig. 11 to 14 A three-stage control of a valve of a cylinder is possible. In the sliding cam systems according to the Fig. 1 to 8 as well as the Fig. 9 and 10 only a two-stage control of a valve of a cylinder is possible, since the respective cam section has only two cam contours 22.

The two sliding cam systems according to the Fig. 11 to 14 are arranged in a cylinder head 25, not shown.

The respective sliding cam system comprises three sliding cam elements 12a, 12b, 12c. The first sliding cam element 12a has, as shown in the Fig. 6 to 10 shown, each has a switching gate 13 with a first switching groove 14a and a second switching groove 14b. The first switching groove 14a is Y-shaped. The first switching groove 14a can also have a different shape.

The second switching groove 14b is, as shown in the Fig. 6 to 10 designed as a radially circumferential groove. In other words, the second switching groove 14b is designed as an annular groove. The second switching groove 14b is arranged at an axial end of the first sliding cam element 12a and borders on the first switching groove 14a. Alternatively, the second switching groove 14b can be arranged at a different axial position on the first sliding cam element 12a.

The switching grooves 14 of the second and third sliding cam elements 12b, 12c are V-shaped.

The sliding cam elements 12a, 12b, 12c each have two cam sections 29, in each of which three cam contours 22 are formed. A first cam section 29a borders on the switching gate 13 of the sliding cam element 12a, 12b, 12c. A second cam section 29b is arranged at a distance from the first cam section 29a in the axial direction. The cam sections 29a, 29b of the respective sliding cam element 12a, 12b, 12c are of the same design. Alternatively, it is possible for the cam sections 29a, 29b of the respective sliding cam element 12a, 12b, 12c to differ from one another.

The total of three cam contours 22 per cam section 29 form two lifting cam contours 31 with different strokes and one zero-lift cam contour 32. The two lifting cam contours 31 are in axial Direction adjacent to each other. The zero-lift cam contour 32 borders on one of the two lifting cam contours 31 in the axial direction.

It is also possible that the respective cam sections 29 do not have a zero-lift cam contour 32, i.e. instead of the zero-lift cam contour 32 they have another lifting cam contour 31. The three lifting cam contours 31 can have different strokes.

By designing the cam sections 29 with three different contours 31, 32, the valve of a cylinder assigned to the respective cam section 29 can be controlled in three different switching positions during operation. Specifically, during operation, two different strokes can be transmitted to the valve by the two lifting cam contours 31 and thus the valve can be actuated. In addition, during operation, the cylinder assigned to the valve can be switched off by the zero-lift cam contour 32. This is referred to as a three-stage control of the cylinder's valve.

The sliding cam system according to the Fig. 11 and 12 has two locking elements 19 which are arranged on the carrier shaft 11 in a rotationally fixed manner. The locking elements 19 are arranged axially between the second and the third sliding cam element 12b, 12c. The locking elements 19 are each formed by a circular disk or an annular disk. The respective circular disk or the annular disk has, as described in the previous embodiments, a recess. The recess extends along a circumferential direction of the circular disk or the annular disk.

The two locking elements 19 are axially spaced apart from one another. The distance between the two locking elements 19 corresponds essentially to the width of a receiving element 18 of the adjusting element 16. The receiving element 18 is formed by a single extension 33 which extends in the direction of the camshaft 10. The extension 33 is designed such that an intermediate space 34 can accommodate the extension 33 axially between the two locking elements 19. The receiving element 18 is arranged between the second and the third coupling pin 17b, 17c.

In contrast to the sliding cam system according to Fig. 11 and 12 is in the sliding cam system according to Fig. 13 and 14 only one locking element 19 is arranged on the carrier shaft 11 in a rotationally fixed manner. However, here the adjusting element 16 Instead of one receiving element 18, it has a total of two receiving elements 18 in the form of extensions 33. The two receiving elements 18 extend in the direction of the longitudinal axis of the carrier shaft 11 and together form a fork shape.

The adjusting element 16 according to Fig. 11 to 14 is arranged offset to the actuator pins 15 at an angle of rotation about the longitudinal axis of the carrier shaft 11. Coupling pins 17a, 17b, 17c are arranged offset in the axial direction on the adjustment element 16. The first coupling pin 17a engages in the second switching groove 14b of the first sliding cam element 12a. The second coupling pin 17b engages in the switching groove 14 of the second sliding cam element 12b and the third coupling pin 17c engages in the switching groove 14 of the third sliding cam element 12c.

According to the Fig. 11 to 14 Furthermore, a multiple actuator 23 is arranged in the area of the first sliding cam element 12a, which has a total of three actuator pins 15. The three actuator pins 15 enable a total of three axial positions of the three sliding cam elements 12a, 12b, 12c.

The first coupling pin 17a is, as described above, permanently engaged with the second switching groove 14b. The continuously encircling second switching groove 14b enables the adjustment element 16 to be moved directly without a time delay, i.e. the adjustment element 16 and the first sliding cam element 12a move essentially simultaneously.

During an axial displacement, one of the three actuator pins 15 engages in the first switching groove 14a, so that the first sliding cam element 12a is moved in the axial direction by the course of the first switching groove 14a. The first sliding cam element 12a and the adjustment element 16 are pushed from a first axial position 36a to a second axial position 36b, which is in particular in the middle in the longitudinal direction of the carrier shaft 11. The second and third sliding cam elements 12b, 12c are axially displaced with a time delay by the coupling pins 17a, 17b.

With the sliding cam system according to Fig. 11 and 12 The individual extension 33 is moved by a first of the two locking elements 19 into the space 34 between the two locking elements 19, whereby the extension 33 absorbs the occurring adjustment forces of the second and third sliding cam element 12b, 12c to the second locking element 19. The extension 33 is located in the second axial position 36b between the two locking elements 19.

With the sliding cam system according to Fig. 13 and 14 In this case, a first of the two extensions 33 is moved axially through the cutout of the locking element 19, whereby the first extension 33 transfers the adjustment forces of the second and third sliding cam elements 12b, 12c to the individual locking element 19. The locking element 19 is located in the second axial position 36b in an area of the outer circumference between the two extensions 33.

By engaging the second, in particular the middle, of the three actuator pins 15 in the longitudinal direction of the carrier shaft 11 in the first switching groove 14a, the first sliding cam element 12a with the adjustment element 16 is pushed to a third, in particular last, axial position 36c. The second and third sliding cam elements 12b, 12c are thereby displaced further axially with a time delay by the coupling pins 17b, 17c.

With the sliding cam system according to Fig. 11 and 12 the extension 33 moves axially outwards from the intermediate space 34 between the two locking elements 19 and cooperates with the second locking element 19 to transmit the adjustment forces. The extension 33 is located at the third axial position 36c on the outside of the second locking element 19. In order to reverse the displacement process, the third actuator pin 15 engages in the first switching groove 14a, whereby the axial displacement direction is in the opposite direction.

With the sliding cam system according to Fig. 13 and 14 the second extension 33 moves axially outwards from the intermediate space 34 between the two locking elements 19 and cooperates with the second locking element 19 to transmit the adjustment forces. The extension 33 is located at the third axial position 36c on the outside of the second locking element 19. In order to reverse the displacement process, the third actuator pin 15 engages in the first switching groove 14a, whereby the axial displacement direction is in the opposite direction.

With the sliding cam system according to Fig. 13 and 14 In this case, a second of the two extensions 33 is moved axially through the cutout of the locking element 19, whereby the second extension 33 transfers the adjustment forces of the second and third sliding cam elements 12b, 12c to the individual locking element 19. In the third axial position 36c, the second extension 33 is located on the further outside of the locking element 19.

A spring-ball lock 24 is arranged between the first and second coupling pins 17a, 17b in order to releasably fix the adjustment element 16 in the longitudinal direction at the axial positions 36a, 36b, 36c. Other shapes are possible instead of the ball.

In summary, in the sliding cam systems according to the invention, a total of three cam contours, in particular lifting cam contours 31, zero-lift cam contours 32, and a multiple actuator 23 with at least three actuator pins 15 are required for a three-stage control of a valve.

The Fig. 15 and 16 In contrast to the sliding cam system according to the Fig. 1 to 4 Instead of two sliding cam elements for controlling valves of only one cylinder, two double sliding cam elements are designed to control valves of two cylinders.

The sliding cam system according to the Fig. 15 and 16 is also arranged in a cylinder head 25, not shown.

The first of the two double sliding cam elements 12a', 12b' has a switching gate 13 with a first switching groove 14a and a second switching groove 14b. The design of the switching gate 13 and the switching grooves 14a, 14b are as in the Fig. 11 to 14 described and arranged.

The switching groove 14 of the second double sliding cam element 12b' is V-shaped.

The double sliding cam elements 12a', 12b' each have four cam sections 29, in each of which two cam contours 22' are formed. Two cam sections 29 are arranged in the longitudinal direction on one axial side of the shift gate 13. In other words, the Switching gate 13 is arranged axially between two pairs of cam sections 29. The two first cam sections 29a of the pairs border on the switching gate 13 of the double sliding cam element 12a', 12b'. The second cam section 29b of the respective pair is arranged at a distance in the axial direction from the first cam section 29a of the same pair. The cam sections 29a, 29b of the respective double sliding cam element 12a', 12b' are of the same design. Alternatively, it is possible for the cam sections 29a, 29b of the respective double sliding cam element 12a', 12b' to differ from one another.

The total of two cam contours 22 per cam section 29 form two lifting cam contours 31 with different strokes. The lifting cam contours 31 are provided adjacent to one another in the axial direction.

It is also possible for the respective cam sections 29 to have a zero-lift cam contour 32 instead of one of the lifting cam contours 31.

By designing the cam sections 29 with two different lifting cam contours 31 each, the valve of a cylinder assigned to the respective cam section 29 can be controlled in two different switching positions during operation. Specifically, during operation, two different strokes can be transmitted to the valve by the lifting cam contours 31 and the valve can thus be actuated. This is referred to as a two-stage control of the cylinder's valve.

Alternatively, it is also possible for the cam sections 29 of the double sliding cam elements 12a', 12b' to have a total of three cam contours 22, so that a three-stage control of a valve of a cylinder is possible.

The sliding process of the double sliding cam elements 12a', 12b' takes place as in the Fig. 1 to 4 described. In the Fig. 15 and 16 Only the actuator with the two actuator pins 15 is not shown. Furthermore, the design of the adjustment element 16 and the locking element 19 corresponds to that shown in Fig. 13 and 14 These differ only in the number of possible axial positions. According to Fig. 15 and 16 Only two axial positions are possible when axially moving the double sliding cam elements 12a', 12b'. Furthermore, in contrast to the Fig. 13 and 14 no two Receiving elements 19 or extensions 33 are not provided, but only a single extension 33.

During operation, the extension 33 transmits the adjustment forces of the second double sliding cam element 12b' to the locking element 19 depending on the respective axial position. The locking element 19 is as in Fig. 11 to 14 Furthermore, the axial displacement process in the sliding cam system takes place according to Fig. 15 and 16 as in the Fig. 1 to 4 described.

According to Fig. 17 a carrier shaft 11 of a further embodiment of a sliding cam system is shown. In contrast to the sliding cam systems described above, the locking element 19 is formed integrally with the carrier shaft 11. The locking element 19 is formed by a recess 37 in the carrier shaft 11. The recess 37 can be formed by milling and/or turning. The recess 37 is formed by two circumferential grooves 38 and a longitudinal passage 39 connecting the grooves 38. The grooves 38 are formed radially circumferentially in the carrier shaft 11.

During operation, the receiving element 18 is partially arranged in one of the two grooves 38 depending on the respective axial position 36a, 36b of the sliding cam element 12a, 12b or double sliding cam element 12a', 12b'. If the axial position 36a, 36b and thus of the adjustment element 16 is changed during operation during a displacement process, the receiving element 18 passes through the longitudinal passage 39 and changes from the first to the second circumferential groove 36a, 36b. The receiving element 18 is supported against the groove walls in order to transfer the forces occurring during the axial displacement to the carrier shaft 11. This design of the recess 37 is used for a two-stage control of the valves, in particular by two contours of the respective cam sections 29. The locking element 19 as recess 37 of the carrier shaft 11 can be used in the sliding cam systems according to the Fig. 1 to 4 and/or Fig. 15 and 16 be used.

In the case of a three-stage control of the valves, in particular by three contours of the respective cam sections 29, the recess 37 can be formed by a total of three circumferential grooves 38 and two longitudinal passages 39. In this case, one longitudinal passage 39 connects two grooves 38, so that when the sliding cam elements 12a, 12b or A total of three axial positions 36a, 36b, 36c are possible for the double sliding cam elements 12a', 12b'. The power transmission from the receiving element 18 to the carrier shaft 11 can take place as described above.

Fig. 18 shows a schematic representation of a part of another embodiment of a sliding cam system. The sliding cam system has a carrier shaft 11 with a locking element 19. The locking element 19 can be arranged as in the Fig. 11 to 14 described. Furthermore, Fig. 18 an adjusting element 16 with a receiving element 18, which is designed as an extension 33. The extension 33 is also as in the Fig. 11 to 14 described. In the sliding cam system according to Fig. 18 the receiving element 18 serves not only for force transmission or support, but also as a stop that limits the axial displacement path. Alternatively or additionally, stop areas 41 are provided in a cylinder head (not shown), against which the adjusting element 16 strikes in the direction of displacement to limit the axial displacement path. For this purpose, the adjusting element 16 has two stop ends 42, which form the longitudinal ends of the adjusting element 16, which strike the respective stop area 41 during operation. Other alternatives for limiting the axial displacement path are possible.

The described embodiments of the invention can be combined with each other, as for example in Fig. 10 and is not limited to the variants described. In particular, the sliding cam systems can be designed according to the Fig. 1 to 5 and 11 to 17 a stop element 27, as in Fig. 7 This applies not only to the design of the stop element 27, but also to the type of design and interaction with the cylinder head cover 25.

In an advantageous embodiment of the invention, it can be provided that the switching gate 13 of the second sliding cam element 12b has a V-shaped profile at least in sections.

In a further advantageous embodiment of the invention, it can be provided that the carrier shaft 11 comprises at least one third, in particular at least one fourth, sliding cam element 12c.

In a further advantageous embodiment of the invention, it can be provided that the sliding cam elements 12a, 12b are designed as double sliding cam elements 12a', 12b', wherein each of the double sliding cam elements 12a', 12b' is designed to control valves of two cylinders.

In a further advantageous embodiment of the invention, it can be provided that the switching grooves 14 of the first and second sliding cam elements 12a, 12b are arranged offset from one another at an angle of rotation such that the second sliding cam element 12b can be displaced along a longitudinal direction of the carrier shaft 11 at a time offset from the first sliding cam element 12a.

In a further advantageous embodiment of the invention, it can be provided that the second and the third sliding cam element 12b, 12c each have a V-shaped profile at least in sections, wherein the V-shaped profiles each have a constant radius.

In a further advantageous embodiment of the invention, it can be provided that the switching grooves 14 of the first, second and third sliding cam elements 12a, 12b, 12c are arranged offset from one another at an angle of rotation such that the second and third sliding cam elements 12b, 12c can each be displaced at a time offset from the first sliding cam element 12a along a longitudinal direction of the carrier shaft 11.

In a further advantageous embodiment of the invention, it can be provided that the sliding cam elements 12a, 12a', 12b, 12b', 12c each have at least one cam section 29, in particular at least two cam sections 29, for controlling a valve of a cylinder in which at least one lifting cam contour 31 is formed for actuating the valve.

In a further advantageous embodiment of the invention, it can be provided that the sliding cam elements 12a, 12a', 12b, 12b', 12c each have at least two cam sections 29, in particular at least four cam sections 29, for controlling valves of two cylinders, wherein in each of the two cam sections 29 at least one Lifting cam contour 31 is designed to actuate the valve of one of the two cylinders.

In a further advantageous embodiment of the invention, it can be provided that the cam section 29 has at least two lifting cam contours 31, in particular at least three lifting cam contours 31, for actuating the valve, wherein the lifting cam contours 31 each comprise different strokes.

In a further advantageous embodiment of the invention, it can be provided that the cam section 29 additionally has at least one zero-lift cam contour 32 for switching off the cylinder assigned to the valve, wherein the zero-lift cam contour 32 adjoins a/the lifting cam contour 31.

In a further advantageous embodiment of the invention, it can be provided that at least one multiple actuator 23 with at least two actuator pins 15, in particular at least three actuator pins 15, is provided, by means of which the sliding cam elements 12a, 12b, 12c can be brought into at least two, in particular three, axial positions 36 in order to enable different switching positions for the valves.

In a further advantageous embodiment of the invention, it can be provided that the first sliding cam element 12a and the multiple actuator 23 are arranged in a first axial region of the carrier shaft 11 and the second and/or third sliding cam element 12b, 12c is/are arranged in a second axial region of the carrier shaft 11 adjacent to the first axial region.

In a further advantageous embodiment of the invention, it can be provided that the first sliding cam element 12a and the multiple actuator 23 are arranged in the longitudinal direction of the carrier shaft 11 between the second and the third sliding cam element 12b, 12c, in particular centrally.

In a further advantageous embodiment of the invention, it can be provided that the locking element 19 has at least in sections a circular disk or an annular disk, wherein the locking element 19 is arranged between the first and the second sliding cam element 12a, 12b or between the second and the third sliding cam element 12b, 12c or the Locking element 19 is arranged between an axle end of the support shaft 11 and one of the sliding cam elements 12a, 12b, 12c.

In a further advantageous embodiment of the invention, it can be provided that the locking element 19 is formed integrally with the carrier shaft 11, wherein the locking element 19 is formed by at least one recess 37, in particular at least two circumferential grooves 38 and at least one longitudinal passage 39 connecting the grooves 38, in the carrier shaft 11.

In a further advantageous embodiment of the invention, it can be provided that at least one camshaft bearing 20, in particular rolling bearing 20 and/or plain bearing, is provided, wherein a part of the camshaft bearing 20 forms the locking element 19.

In a further advantageous embodiment of the invention, it can be provided that the carrier shaft 11 has at least two locking elements 19 and the receiving element 18 of the adjusting element 16 forms at least one extension 33 which cooperates with one or both locking elements 19 during operation, so that at least one of the two locking elements 19 can be at least partially subjected to the forces acting upon a change in position of the second and/or third sliding cam element 12b, 12c.

In a further advantageous embodiment of the invention, it can be provided that the carrier shaft 11 has at least one locking element 19 and the receiving element 18 of the adjusting element 16 forms at least two extensions 33 which interact with the locking element 19 during operation, so that the locking element 19 can be at least partially subjected to the forces acting upon a change in position of the second and/or third sliding cam element 12b, 12c.

In a further advantageous embodiment of the invention, it can be provided that a stop 26 is formed in a cylinder head 25, in particular in a cylinder cover, and the adjusting element 16 has a stop element 27 which cooperates with the stop 26 in the cylinder head 25 such that the axial displacement of the adjusting element 16 is limited.

In a further advantageous embodiment of the invention, it can be provided that the receiving element 18 is the stop element 27 and limits the axial displacement of the adjusting element 16 during operation.

In a further advantageous embodiment of the invention, it can be provided that the adjusting element 16 has at least one stop end 42 in the direction of displacement, which during operation cooperates with a counterpart, in particular the cylinder head 25, such that the axial displacement of the adjusting element 16 is limited.

In a further advantageous embodiment of the invention, it can be provided that the locking element 19 is arranged on the carrier shaft 11 in a rotationally fixed manner and is displaceable along a longitudinal direction of the carrier shaft 11, wherein the locking element 19 is guided axially in the cylinder head 25, in particular in the cylinder head cover.

In a further advantageous embodiment of the invention, it can be provided that the locking element 19 is arranged on the carrier shaft 11 in a rotationally fixed manner and is fixed in the longitudinal direction of the carrier shaft 11.

In a further advantageous embodiment of the invention, it can be provided that the adjusting element 16 is arranged at an angle of rotation offset from the at least one actuator pin 15.

In a further advantageous embodiment of the invention, it can be provided that the second switching groove 14b is arranged at an axial end of the first sliding cam element 12a next to the first switching groove 14a or the second switching groove 14b is arranged between two axial ends of the first sliding cam element 12a, wherein the second switching groove 14b extends substantially over the entire circumference of the first sliding cam element 12a.

In a further advantageous embodiment of the invention, it can be provided that the first switching groove 14a of the first sliding cam element 12a is at least partially Y-shaped or at least partially S-shaped.

list of reference symbols

10

camshaft

11

carrier wave

12a

first sliding cam element

12b

second sliding cam element

12c

third sliding cam element

13

shift gate

14

shift groove

14a

first shift groove

14b

second shift groove

15

actuator pin

16

adjustment element

17a

first coupling pin

17b

second coupling pin

17c

third coupling pin

18

receiving element

19

locking element

20

rolling bearings

21

retaining rings

22

cam contour

23

actuator, multiple actuator

24

spring-ball locking mechanism

25

cylinder head

26

stop

27

stop element

28

Axial bearing

29

cam section

29a

first cam section

29b

second cam section

31

lifting cam contour

32

zero-lift cam contour

33

appendix

34

space between

36a

first axial position

36b

second axial position

36c

third axial position

37

recess

38

circumferential grooves

39

longitudinal passage

41

stop areas

Claims (15)

1. Shift cam system for an internal combustion engine with at least one camshaft (10), comprising a carrier shaft (11) with at least two shift cam elements (12a, 12b), which each comprise a shift gate (13) with at least one shift groove (14), wherein the shift cam elements (12a, 12b) are axially displaceable relative to the carrier shaft (11) by at least one actuator pin (15) and at least one adjusting element (16) is arranged parallel to a longitudinal axis of the carrier shaft (11), wherein the adjusting element (16) is axially displaceable in the direction of the longitudinal axis of the carrier shaft (11),
   wherein
   the adjusting element (16) has at least two coupling pins (17a, 17b), wherein a first coupling pin (17a) is arranged in the region of the first sliding cam element (12a) and a second coupling pin (17b) is arranged in the region of the second sliding cam element (12b) and the coupling pins (17a, 17b) each co-operate with a switching gate (13) of the respective associated sliding cam element (12a, 12b) in such a way that a movement of the first sliding cam element (12a) initiated by the actuator pin (15) can be transmitted to the second sliding cam element (12b) by the adjusting element (16), characterised in that the coupling pins (17a, 17b) cooperate with the switching groove (14) of the switching gate (13).
2. Shift cam system according to claim 1,
   characterised i n that
   the adjusting element (16) comprises at least one receiving element (18) and the carrier shaft (11) comprises at least one locking element (19), which interact with one another during operation in such a way that the adjusting element (16) is locked between two position changes.
3. Shift cam system according to claim 2,
   characterised i n that

   the locking element (19) forms an abutment for the receiving element (18), so that the locking element (19) can be

   at least partially subjected to

   the forces acting during the change in position of the at least second sliding cam element (12b).
4. Shift cam system according to one of the preceding claims, characterised i n that
   the adjusting element (16) comprises a spring-ball locking device.
5. Shift cam system according to one of the preceding claims, characterised i n that
   the at least one actuator pin (15) and the at least two coupling pins (17a, 17b) are offset in a circumferential direction of the carrier shaft (11), in particular by 90°.
6. Shift cam system according to one of the preceding claims, characterised i n that
   the switching gate (13) of the first sliding cam element (12a) comprises at least one first switching groove (14a) and at least one second switching groove (14b), wherein the first switching groove (14a) is provided for receiving the at least one actuator pin (15) and the second switching groove (14b) is provided for receiving the first coupling pin (17a).
7. Shift cam system according to one of the preceding claims, characterised i n that
   the first switching groove (14a) and the second switching groove (14b) have the same angle of rotation, the radius of the first switching groove (14a) being greater than the radius of the second switching groove (14b).
8. Shift cam system according to claim 7,
   characterised i n that
   the first and second switching grooves (14a, 14b) of the first sliding cam element (12a) have a V-shaped profile at least in sections.
9. Shift cam system according to one of claims 1 to 6,
   characterised i n that
   the first switching groove (14a) of the first sliding cam element (12a) has a Y-shaped profile at least in sections.
10. Shift cam system according to claim 9,
    characterised i n that

    the first sliding cam element (12a) comprises

    a second switching groove (14b) for the first coupling pin (17a), which is arranged such that the adjusting element (16) is directly displaceable.
11. Shift cam system according to claim 9 or 10,
    characterised i n that
    the second switching groove (14b) for the first coupling pin (17a) is arranged at least in sections centrally in the Y-shaped first switching groove (12a) and the second switching groove (14b) extends substantially over the entire circumference.
12. Shift cam system according to claim 11,
    characterised i n that
    the second switching groove (14b) is designed as a groove extending over the circumference, in particular an annular groove, with a constant radius, in which the first coupling pin (17a) is permanently arranged in such a way that an axial displacement of the first sliding cam element (12a) can be transmitted directly to the adjusting element (16).
13. Shift cam system according to one of the preceding claims,
    characterised i n that
    the first switching groove (14a) of the first sliding cam element (12a) has regions with different radii, which are each assigned to at least one region of the first sliding cam element (12a), in particular a retraction region, a displacement region and an ejection region.
14. Shift cam system for an internal combustion engine with at least one camshaft (10) comprising a carrier shaft (11) with at least two double shift cam elements (12a', 12b'), which are each designed to control valves of two cylinders, wherein the double shift cam elements (12a', 12b') each comprise a shift gate (13) with at least one shift groove (14) and at least one cam section (29) with at least one lift cam contour (31), wherein the double sliding cam elements (12a', 12b') are axially displaceable relative to the carrier shaft (11) by at least one actuator pin (15), and wherein at least one adjusting element (16) is arranged parallel to a longitudinal axis of the carrier shaft (11) and is axially displaceable in the direction of the longitudinal axis of the carrier shaft (11), characterised i n that
    the adjusting element (16) has at least two coupling pins (17a', 17b'), wherein a first coupling pin (17a') is arranged in the region of the first double sliding cam element (12a') and a second coupling pin (17b') is arranged in the region of the second double sliding cam element (12b') and the coupling pins (17a', 17b') co-operate in each case with a switching gate (13) of the respectively associated double sliding cam element (12a', 12b') in such a way that a movement of the first double sliding cam element (12a') initiated by the actuator pin (15) can be transmitted to the second double sliding cam element (12b') by the adjusting element (16), the coupling pins (17a, 17b) co-operating with the switching groove (14) of the switching gate (13).
15. Motor with at least one shift cam system, in particular several shift cam systems, according to one of the preceding claims.

Images