EP1561012B1 - Rotary actuator system for controlling the stroke of gas exchange valves in the cylinder head of an internal combustion engine - Google Patents

Abstract

The invention relates to a rotary actuator system (1, 1a) for controlling the stroke of at least two gas exchange valves (2, 2', 3, 3') with an identical action in a cylinder head (4) of an internal combustion engine. Said system consists of a first pivoting motor (5), equipped with a first shaft (6), on which at least one first actuating element (7, 7a) is located and a second pivoting motor (5 ), equipped with a second shaft (6'), on which at least one second actuating element (7', 7a') is located. One actuating element (7, 7a, 7', 7a') is provided for at least one gas exchange valve (2, 2', 3, 3') and the first and second pivoting motors (5, 5') are point-symmetrical. A force transmission element (8, 8a, 8', 8a') is located between the actuating element (7, 7a, 7', 7a') and the gas exchange valve (2, 2', 3, 3'). The inventive configuration in the valve train reduces the masses that are displaced, permitting higher speeds during the operation of the internal combustion engine.

Description

The invention relates to a rotary actuator device for stroke control of at least two identical gas exchange valves in a cylinder head of an internal combustion engine according to the features in the preamble of patent claim 1.

It starts from the German publication DE 198 25 964 A1 out. In this, a valve train for an internal combustion engine is proposed, which is designed as a spring-mass vibration system. It consists essentially of a swivel motor with a longitudinally extending in the cylinder head shaft, and a lever-like exciter device for each gas exchange valve. The exciter devices can be coupled to the shaft in accordance with the operating state of the internal combustion engine. The swivel motor only performs a pivoting movement in the sense of a stroke of the gas exchange valves. The shaft and the exciter devices which can be coupled thereto are virtually a camshaft with releasable cams. At the end of each cam, at the point of contact with the gas exchange valve, a roller is arranged to minimize friction. The valve train has two mutually point mirrored swivel motors, each with associated camshaft for all the same gas exchange valves.

A disadvantage of the described embodiment, the large inertial forces and the resulting moments that limit the maximum speed of the internal combustion engine.

Object of the present invention is therefore to reduce the moving masses in a generic valve train.

This object is solved by the features in the characterizing part of patent claim 1.
Advantageously, in an embodiment according to claim 1, the moving masses are reduced in the valve train. The reduction in mass also reduces the resulting moments and thus the mechanical load on the entire valve train, as a result of which higher rotational speeds are possible. In addition, the internal friction of the valve train is substantially reduced, whereby the fuel consumption of the internal combustion engine decreases.

In the embodiment according to claim 2 creates a compact small drive unit for two cylinders. This unit can be expanded in conjunction with claim 9 to a modular concept, so that this unit can be used for any internal combustion engine whose number of cylinders per cylinder row is divisible by 2. A selective structural adaptation to the respective internal combustion engine is not necessary in this modular design.

This modular structure is further elaborated in claim 3. In this embodiment variant, both the inlet and the outlet side of the individual cylinder pairs are constructed with the same modular assemblies. By this measure, the production costs are reduced.

Particularly noteworthy is in claim 4, that in a two-sided obstruction of the valve drive device, both inlet and outlet side, only a parallel displacement of the rotary actuator device must be performed. Further adaptation work on the cylinder head is not necessary.

The embodiment according to the claims 5 to 7 serves to reduce friction in the valve train with simultaneous backlash of the valve train components. The support of the power transmission element, on the one hand on a hydraulic valve clearance compensation element and on the other hand on a gas exchange valve, reduces the moving masses, since in this arrangement, the hydraulic valve clearance compensation element can be arranged in the cylinder head, whereby at the same time a safe and simple oil supply is ensured, Compared to the prior art, in which a bucket tappet is arranged between the rotating means and gas exchange valve, the cup in the embodiment according to the invention is completely eliminated, whereby this mass is eliminated from the moving valve train.

In order to achieve a compact design, according to claim 8, the axes of the spark plug holes in the extension region of a device can be entangled against each other in order to maintain good insertion and removal conditions of the ignition device, such as. a spark plug to obtain the smallest possible compact unit for the rotary actuator device. The size of a device is again significantly reduced by this measure in the modular structure.

A further reduction of the size is achieved by the embodiment according to claim 10, since in such an embodiment, the stator surrounding the rotor does not extend over 360 ° radially on the circumference. By this design variant, the highest packing density of components is achieved.

Fig. 1

zeigt eine schematische Darstellung einer Aufsicht auf zwei einlasssowie auslassseitig auf einem Zylinderkopf einer Brennkraftmaschine verbauten Drehaktor-Vorrichtung,

Fig. 2

zeigt eine schematische Darstellung einer Seitenansicht von zwei einlass- sowie auslassseitig auf einem Zylinderkopf einer Brennkraftmaschine verbauten Drehaktor-Vorrichtung.

In the following the invention with reference to a preferred embodiment is explained in more detail in two figures.

Fig. 1

shows a schematic representation of a plan view of two inlet and outlet side installed on a cylinder head of an internal combustion engine Drehaktor device,

Fig. 2

shows a schematic representation of a side view of two inlet and outlet side installed on a cylinder head of an internal combustion engine rotary actuator device.

The reference numerals in Fig. 1 also apply to the same components in Fig. 2 ,

Fig. 1 shows a schematic plan view of two inlet and outlet side on a cylinder head 4, an internal combustion engine, not shown, built rotary actuator devices 1, 1a, for the stroke control of four equivalent gas exchange valves 2, 2 ', 3, 3'. The structure consists essentially of the first rotary actuator device 1 and the second, for the first parallel shifted, rotary actuator device 1a. Between the rotary actuator devices 1 and 1a, in the cylinder head 4, not shown, a first bore 10 and a second bore 10 'are arranged. The first bore 10 and the second bore 10 'are each arranged centrally to a cylinder, not shown. The first bore 10 and the second bore 10 'serve to receive an ignition device, not shown, for each cylinder. The rotary actuator devices 1, 1a are identical and differ only by the location of the obstruction. The rotary actuator device 1 is provided for an intake side, the rotary actuator device 1 a for an exhaust side of the internal combustion engine. In the following, only the rotary actuator device 1 will be explained in more detail, since all information can be transferred to the second rotary actuator device 1a.

The rotary actuator device 1 essentially has a first and a second, point-mirrored, half rotary actuator device 14, 14 'for the stroke control of two identical gas exchange valves. The first half Drehaktor device 14 consists of a first pivot motor 5 with a stationary first shaft 6, to which two first actuating elements 7, 7a are arranged stationary. The first actuating elements 7, 7a, here cams, interact with a respective first force transmission element 8, 8a. The power transmission elements 8, 8a are supported on one side each on a first clearance compensation element 9, 9a and on the opposite side in each case on a first gas exchange valve 2, 2 'from. The same applies to the second half rotary actuator device 14 '. This consists of a second pivot motor 5 ', with a stationary second shaft 6'. To the second shaft 6 ', two further second actuating elements 7', 7a 'are arranged stationary. These are in interaction with two second power transmission elements 8 ', 8a', which in turn on the one hand to two second clearance compensation elements 9, 9a 'and on the other hand on two second gas exchange valves 3, 3' are supported.

In the present embodiment, the rotary actuator device 1, consisting of the first and the second half rotary actuator device 14, 14 'is provided for two cylinders of the internal combustion engine. Each half rotary actuator device 14, 14 'actuates two identical gas exchange valves, here the inlet gas exchange valves for two cylinders of the internal combustion engine. In a further embodiment, a half Drehaktor device 14, 14 'may be provided only for a single gas exchange valve. Also, the use of a half Drehaktor device 14, 14 'for two cylinders, each with only one gas acting equivalent valve is possible.

In the present embodiment, the first gas exchange valves 2, 2 'and the second gas exchange valves 3, 3' on a line, whereby the first shaft 6 and the second shaft 6 'and the first and second half Drehaktor device 14, 14' in parallel aligned with each other. However, in other variants, the gas exchange valves can also assume a different position, whereby slightly different geometric arrangements are conceivable.

The first shaft 6 and the second shaft 6 'are camshafts and the first actuators 7, 7a and the second actuators 7', 7a 'are cams. The first power transmission elements 8, 8a and the second power transmission elements 8 ', 8a', are rocker arms, however, it is also possible to use rocker arms or roller rocker arms. The first clearance compensation elements 9, 9a and the second clearance compensation elements 9 ', 9a' are hydraulic valve clearance compensation elements, which are preferably incorporated directly into the cylinder head 4. As a result, a simple hydraulic supply is possible. All features that are shown for the rotary actuator device 1, also apply to the second rotary actuator device 1a.

Fig. 2 shows a schematic side view of the two rotary actuator device 1, 1a. Between the rotary actuator device 1 and the second rotary actuator device 1a is the first bore 10, for a not shown ignition device for the first cylinder. As under Fig. 1 already described the two rotary actuator devices 1 and 1 a are identical and point-only mirrored to each other, only the rotary actuator device 1 will be explained in more detail below again.

Above the valve stem end of the gas exchange valve 3, an inlet gas exchange valve, are juxtaposed the first half rotary anchor device 14, proximate to the first bore 10, and the second half rotary anchor device 14 ', further spaced from the first bore 10, on the cylinder head 4 attached. On the first pivot motor 5, a first stator 12 and a first rotor 13 can be seen, on the second pivot motor 5 'only the second stator 12' can be seen, the second rotor 13 'is of the centrally disposed second shaft 6', and the second actuator 7a 'obscured. The actuating element 7a 'rests on the schematically illustrated first force transmission element 8a'. The power transmission element 8a 'is supported on the one hand on the clearance compensation element 9a' and on the other hand on the gas exchange valve 3, which is mounted in the cylinder head 4. The gas exchange valve 3 is shown in the open position and closes in a closed position an intake passage 15 in the cylinder head 4. The corresponding outlet gas exchange valve 2 is also shown in the open position and closes in the closed position an exhaust passage 16 in the cylinder head 4th

In order to achieve the highest possible component density and thus a small size, the first stator 12 or the second stator 12 'surround the first rotor 13 and the second rotor 13' radially not on the entire circumference, but only approximately 270 °. The enclosure is preferably greater than 180 °, but always less than 360 °, whereby the mutually parallel shafts 6, 6 'structurally closer. This arrangement brings not only package advantages but also weight advantages. A further reduction in size is possible because the first bore 10 with the first axis 11 and the second bore 10 'with the second axis 11' are interlocked with each other, since in the embodiment according to the invention on the inlet side and on the outlet side a gas exchange valve and a clearance compensation element, respectively which have different space requirements.

LIST OF REFERENCE NUMBERS

1

Rotary actuator device

1a

Second rotary actuator device

2, 2 '

First gas exchange valve

3, 3 '

Second gas exchange valve

4

cylinder head

5

First swing motor

5 '

Second swing motor

6

First wave

6 '

Second wave

7, 7a

First actuator

7 ', 7a'

Second actuator

8, 8a

First power transmission element

8 ', 8a'

Second power transmission element

9, 9a

First clearance compensation element

9 ', 9a'

Second clearance compensation element

10

First drilling

10 '

Second hole

11

First axle

11 '

Second axis

12

First stator

12 '

Second stator

13

First rotor

13 '

Second rotor

14

First half rotary anchor device

14 '

Second half rotary anchor device

15

inlet channel

16

exhaust port

Claims (9)

1. A cylinder head comprising a rotary actuator (1, 1a) for controlling the stroke of at least two equally acting gas change valves (2, 2', 3, 3') in a cylinder head (4) of an internal combustion engine, the actuator comprising a first swivel motor (5) with a first shaft (6) on which at least one first actuating element (7, 7a) is disposed and a second swivel motor (5') with a second shaft (6') on which at least one second actuating element (7', 7a') is disposed, wherein an actuating element (7, 7a, 7', 7a') is provided for at least one gas change valve (2, 2', 3, 3') and the first and the second swivel motor (5, 5') are disposed in point mirror arrangement,
   characterised in that a force transmitting element (8, 8a, 8', 8a') is disposed between the actuating element (7, 7a, 7', 7a') and the gas change valve (2,2', 3,3'), wherein the engine comprises at least one first cylinder with a first ignition device in a bore in the cylinder head and one second cylinder with a second ignition device in a bore in the cylinder head and wherein at least a first axis (11) of the first bore (10) crosses or overlaps a second axis (11') of the second bore (10').
2. A cylinder head according to claim 1, wherein the engine has at least two cylinders,
   characterised in that at least one rotary actuator (1) is provided for two cylinders.
3. A cylinder head according to claim 1 or claim 2, wherein each cylinder has an inlet side and an outlet side,
   characterised in that the inlet side is associated with at least one first actuator (1) and/or the outlet side is associated with at least one second actuator (1a).
4. A cylinder head according to claim 3,
   characterised in that the second rotary actuator (1a) is offset in parallel with the first actuator (1).
5. A cylinder head according to any of the previously-mentioned claims,
   characterised in that the force transmitting element (8, 8a, 8', 8a') is a drag lever or a roller drag lever or a rocker arm.
6. A cylinder head according to any of the previously-mentioned claims,
   characterised in that the force transmitting element (8, 8a, 8', 8a') abuts a clearance compensating element (9, 9', 9a, 9a') on one side and a gas change valve (2, 2', 3, 3') on the other side.
7. A cylinder head according to claim 6,
   characterised in that the clearance compensating element (9, 9', 9a, 9a') is a hydraulic valve clearance compensating element.
8. A cylinder head according to any of the previously-mentioned claims,
   characterised in that at least two rotary actuators (1, 1a) are disposed in line with one another along a longitudinal axis of the engine.
9. A cylinder head according to any of the previously-mentioned claims, wherein the swivel motor comprises a stator and a rotor,
   characterised in that the stator (12) extends at least 180 radially round the rotor (13).

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