JP2011518290A - Device for adjusting the amount of eccentricity for a crank CVT transmission - Google Patents

Abstract

  An apparatus for adjusting the amount of eccentricity of a rotational axis of an eccentric member relative to a rotational axis of a crank shaft of a crank CVT transmission, wherein the crankshaft having at least one guide region for the eccentric member is provided. The outer peripheral surface of the eccentric member is suitable for fitting a rolling bearing, has a worm, the crankshaft has a hollow chamber in the axial direction, and the worm has a crankshaft. Is inserted into the hollow chamber. Furthermore, in order to displace the eccentric member constituting member in the direction perpendicular to the axial direction of the crankshaft by the rotation of the worm, a displacement unit is provided in at least one guide region.

Description

  The present invention relates to a crank CVT transmission, and more particularly to an adjusting device for adjusting a drive shaft of a crank CVT transmission for changing an eccentric amount of an eccentric member constituting a drive shaft.

  A crank CVT transmission is known, for example, in DE 10243533 A1. In this transmission, a displaceable eccentric body drive device including an eccentric body constituting member is provided on an input shaft that can be driven by an engine and forms a drive shaft in relation to the transmission. The eccentric body driving device is coupled to the driven shaft via a connecting rod-shaped coupling member. The driven shaft forms an output shaft in relation to the transmission. The driven shaft is driven by the stroke of the coupling member being transmitted to the shaft via the freewheel device. The freewheel device is provided between the coupling member and the driven shaft.

  Furthermore, the device in German Offenlegungsschrift 10 243 533 is provided with an electric machine. The electric machine can be selectively connected via drive means only to the drive side of the transmission, only to the engine, or simultaneously to the drive side and the engine. The drive side of the transmission is formed by a driven shaft, and the engine is formed by an internal combustion engine.

  The drive shaft has a notch extending in the axial direction of the shaft for adjusting the amount of eccentricity and thus for adjusting the stroke of the coupling member. The notch houses the displacement shaft. The displacement shaft is rotatably supported in the notch. The displacement shaft has an outer dentition, and the teeth of the outer dentition engage with the teeth of the inner dentition of the eccentric member. The displacement shaft is centered or supported in the notch of the drive shaft via the outer dentition section forming the addendum circle of the outer dentition. By the rotation of the displacement shaft with respect to the drive shaft, the eccentric member constituting member of the eccentric member unit rotates or turns around the corresponding guide region via the tooth rows engaged with each other. The center line of the eccentric member constituting member changes along a circle having the center point as the center point of the guide region by the rotation of the displacement shaft. An interval decrease or increase occurs. This means that the amount of eccentricity of the eccentric member relative to the rotational axis of the drive shaft is reduced or increased, and consequently the amount of stroke that can be transmitted to the coupling member or connecting rod is also reduced or increased.

  The objective of this invention is providing the apparatus which adjusts the eccentric amount of the eccentric body structural member with respect to the rotating shaft line of an input shaft which can transmit the high drive moment of a crankshaft. Furthermore, an object of the present invention is to provide a crank CVT transmission provided with the above device.

  The object is achieved by a device for adjusting the amount of eccentricity comprising the features of claim 1 or a crank CVT transmission comprising the features of claim 8. Advantageous configurations are set forth in the dependent claims.

  The philosophy underlying the present invention uses a drive shaft having a spur gear adjustment portion provided in a known crank CVT transmission and a worm drive device having a thread adjustment portion for changing the amount of eccentricity. It is to exchange with the drive shaft to do. Thus, since a self-locking screw thread can be used, unlike the known configuration, it is not necessary to continuously energize the adjustment motor during constant running, that is, when there is no change in the gear ratio. Furthermore, since a very high gear ratio can be achieved as a whole from the combination of the screw thread drive and the worm drive, no extra transmission is required for adjustment. This also provides advantages with respect to weight and construction space. As a result, the crankshaft can be configured with extremely high rigidity based on the largest possible cross-section, so that a high driving moment can be transmitted.

  In particular, an apparatus according to the present invention for adjusting the amount of eccentricity of the rotational axis of the eccentric member relative to the rotational axis of the crankshaft of the crank CVT transmission accommodates a coupling member, for example, a connecting rod-shaped coupling member. A crankshaft having at least one guide region for an eccentric member having an outer peripheral surface suitable for fitting of the rolling bearing, and a worm. The crankshaft has a hollow chamber extending in the axial direction. A worm is inserted into the hollow chamber and is supported so as to be non-slidable in the axial direction, although it is rotatable. In at least one guide region of the crankshaft, a displacement unit for sliding the eccentric member is provided in a direction perpendicular to the axial direction of the crankshaft engaged with the worm. Is performed by rotating the worm.

  Advantageously, the eccentric body component consists of two members. Both members are coupled by, for example, screwing at the time of assembly to the crankshaft to form an eccentric member constituting member unit. This allows easy assembly.

  According to an advantageous configuration, the at least one guide region is arranged eccentrically with respect to the axis of the crankshaft. In particular, when a plurality of guide areas are provided and all of these guide areas are arranged eccentrically with respect to the axis of the crankshaft, the eccentric member is additionally added from this position by the displacement unit. It is also possible to provide a stroke at the starting position without being moved. Therefore, since the predetermined gear ratio can be already achieved in the starting state, the moving distance of the eccentric member can be kept relatively small. Alternatively, if the moving distance of the eccentric member provided by the displacement unit is selected to be relatively large and at the same time the eccentric member is provided in the eccentric guide region itself, the crank CVT transmission The spread of the gear ratio (Spreizung) can be increased.

  According to a particularly advantageous configuration, the displacement unit has a worm wheel that engages the worm. The worm wheel is stationary in the direction of displacement, but is rotatably supported in the guide region, and is coupled to the eccentric body component member via a thread device, so that the thread between the worm wheel and the thread device is By changing the position of the device, the eccentric member can slide relative to the crankshaft.

  According to another particularly advantageous configuration, the thread device is configured as a self-locking thread. Thus, it can be said that the drive motor for the worm is energized only when it is desired to actually change the transmission gear ratio.

  The screw thread device may be configured as a fixed screw, that is, a screw that is supported on the eccentric member so as not to rotate. In this configuration, the corresponding thread is formed on the worm wheel as a female thread.

  Advantageously, a plurality of guide areas and eccentric body components are arranged along the axial direction of the crankshaft together with the arranged displacement units. Since the displacement unit can be moved by one common worm, synchronous displacement of all the eccentric body components is guaranteed.

It is a perspective view of a crank CVT transmission. It is a perspective view of the apparatus which adjusts the amount of eccentricity of the transmission shown in FIG. 1, and the amount of eccentricity is the minimum. It is a figure corresponding to Drawing 2A, and the amount of eccentricity is the maximum. It is a front view of the apparatus which adjusts the amount of eccentricity, and the amount of eccentricity is the minimum. It is a figure corresponding to Drawing 3A, and the amount of eccentricity is the maximum. It is a cross-sectional view of the device for adjusting the amount of eccentricity in a plane perpendicular to the axial direction of the crankshaft. It is a cross-sectional view in the longitudinal direction of the device for adjusting the amount of eccentricity, the amount of eccentricity is the smallest. It is a figure corresponding to Drawing 5A, and the amount of eccentricity is the maximum. It is a perspective view of the drive shaft which is not provided with the worm wheel unit. It is a perspective view of the drive shaft provided with the worm wheel unit. It is a perspective view of a drive shaft provided with a screw transmission. It is a perspective view of a drive shaft provided with a screw transmission. It is a perspective view of a worm wheel unit. It is sectional drawing of a worm wheel unit. It is a perspective view of a worm wheel. It is a perspective view of the screw provided with the rotation prevention part used for the apparatus which adjusts the amount of eccentricity.

  Hereinafter, the present invention will be described by way of example with reference to the accompanying drawings.

  The crank CVT transmission 1 (casing is not shown) shown in the perspective view of FIG. 1 is oriented parallel to each other, and is rotatably supported by a casing (not shown). And a driven shaft 5. For example, torque introduced from the internal combustion engine to the crankshaft 4 is transmitted to the driven shaft 5 by the crank CVT transmission, and can act on the driven shaft 5 to drive, for example, a vehicle wheel. The transmission 1 provides an appropriate gear ratio.

  Further, the drive crankshaft 4 and the driven shaft 5 (output shaft) are connected to each other via a rolling bearing by connecting a connecting rod-shaped coupling member 8 arranged in the axial direction of the crankshaft 4 on the crankshaft 4. Driven via a plurality of eccentric body units 6 that are supported, and a corresponding plurality of freewheel units 7 that are arranged axially on the driven shaft 5 and that are connected to each other by a connecting member. Are connected to each other.

  A connecting rod-shaped coupling member 8 is rotatably supported on each free wheel unit 7 in a pivotal attachment region 47 formed integrally with the outer ring 45 of the free wheel unit 7. The freewheel unit 7 itself is formed by a polygonal contour 50 formed on the outer peripheral surface of the driven shaft 5 in association with a clamp body 42 formed by a roller. The clamp body 42 is inserted between the polygonal contour 50 and the inner peripheral surface of the outer ring 45. Thus, the clamping action is achieved in relation to the roller which is the clamping body 42 via the contoured inner travel path as a “roller freewheel”. In one relative rotation direction between the outer ring 45 and the shaft 5, the clamp body 42 can relatively block the rotation of the above components, and the shaft 5 and the outer ring can only rotate together. Does not move. In other relative rotation directions, the locking action by the clamp body 42 is not formed, or a so-called switchable freewheel is provided. The switchable freewheel has two block positions in addition to a neutral position that allows relative rotation of the shaft 5 and the outer ring 45. In the two block positions, the two constituent members are blocked in the first or second relative rotation direction, and rotate together in the first and second rotation directions. Thereby, the rotation direction of the driven shaft 5 that is the output shaft can be changed, and for example, reverse movement can be performed.

  2A to 12 show the assembled eccentric body unit 6 and the individual components of the eccentric body unit 6 in detail. 2A to 5B, various devices 10 for adjusting the amount of eccentricity of the rotational axis of the eccentric member 12 provided on the crankshaft 4 with respect to the rotational axis of the crankshaft 4 are illustrated differently. ing. That is, the device 10 is shown in a perspective view in FIGS. 2A and 2B, and the eccentric member 12 has different eccentric amounts in FIGS. 2A and 2B. 3A and 3B are front views of the crankshaft 4, and the eccentric member 12 also has different eccentric amounts. FIG. 4 is a sectional view, and the section is a cut surface perpendicular to the axial direction of the crankshaft 4. 5A and 5B are longitudinal sectional views along the axial direction of the crankshaft 4, and different eccentric amounts are also shown.

  As shown in the drawings, an apparatus 10 for adjusting the amount of eccentricity has a plurality of eccentric body units 6 each having an eccentric body constituting member 12 disposed on a crankshaft 4 one after the other in the axial direction. ing. Since the eccentric body unit 6 is configured substantially the same, only one will be described here.

  In particular, rolling bearings 17, such as ball bearings, are arranged around a plurality of eccentric body constituting members 12 that are formed in a circular shape as a whole. Via a rolling bearing 17, a coupling member 8, which is only schematically shown in FIGS. 2A to 4, is supported. Bearings via other suitable bearings instead of ball bearings are likewise possible for the coupling member 8.

  Each eccentric member 12 consists of two halves 13 and 14 that are provided by bisecting the eccentric member 12 approximately along the diametrical direction. When the crankshaft 4 is assembled, the halves 13 and 14 of the eccentric member are screwed together by screws 15 by notches and threads provided in the halves 13 and 14 (see FIG. 4).

  The eccentric member 12 is supported in a suitable guide area 18 of the crankshaft 4 so as to be movable in a plane perpendicular to the axis of the crankshaft. The guide area 18 is an eccentric area disposed on the crankshaft 4. The eccentric area is configured as a slider guide. A crankshaft 4 with a suitable guide area 18 can be best seen in FIG. In the embodiment shown in FIG. 6, four guide regions 18 are provided, and the provided eccentric member 12 can move in the guide regions 18 provided. Since the four guide areas 18 are provided, these guide areas 18 are rotated by 90 ° with respect to the axis of the crankshaft in the circumferential direction. As a result, the moving direction of the eccentric member is also shifted in the circumferential direction of the crankshaft axis by 90, and the eccentric amount inherent to the eccentric member 12 is also the axis of the crankshaft 4. Therefore, the strokes provided by the individual eccentric member 12 are equal when the crankshaft 4 is rotated 360 °, that is, at the same angular interval, from the crankshaft 4 to the crank CVT. It is transmitted to the driven shaft 5 of the transmission. When more than four eccentric body units 6 are provided, these eccentric body units 6 can be appropriately shifted in the circumferential direction based on the same amount of eccentricity with respect to the moving direction, and , And can be appropriately shifted based on the orientation of the eccentric body unit 6. In particular, the guide region 18 is moved from the center to the same extent with respect to the axis of the crankshaft 4, that is, has the same amount of eccentricity. In the case of n guide regions 18, 360 ° It is important that they are arranged to rotate with respect to each other by / n.

  As shown in the cross section of FIG. 4, the displacement unit 20 that adjusts the amount of eccentricity of the rotational axis of the eccentric member 12 relative to the rotational axis of the crankshaft 4 can be seen optimally from FIG. 7. , Provided in the guide region 18 of the crankshaft 4. The displacement unit 20 is shown in a perspective view in FIG. 9, and is specifically shown in a sectional view in FIG.

  In particular, the displacement unit 20 has a worm wheel 22 which is also shown in a perspective view in FIG. The worm wheel 22 has an internal thread 24, and the internal thread 24 extends over the worm wheel in the displacement direction of the eccentric member 12 and is configured as a self-locking thread 24. The screw thread 24 engages with a screw 26 (shown in FIG. 12) that is supported in each eccentric member 12 so as not to rotate in the displacement direction. The thread 24 and the male thread of the screw 26 together form a screw device. By rotation of the worm wheel 22 with respect to the screw 26, the worm wheel 22 that is supported so as not to slide in the displacement direction on the crankshaft 4 and the stationary screw 26 with respect to the eccentric member 12 are displaced relative to each other. Moved in the direction. Thereby, adjustment and change of the eccentric amount of the eccentric member 12 with respect to the crankshaft 4 are performed.

  In order to prevent the rotation of the screw 26, the opposite end portions of the screw 26 have a polygonal outline, specifically, a rectangular extension portion 27 in the present embodiment. The extension 27 engages with a corresponding notch provided in the eccentric member, and thus prevents the screw 26 from rotating. The thread of the screw 26 is formed as a male thread and corresponds to the female thread 24 in the worm wheel 22 based on the self-locking action.

  In order to support the displacement unit 20 in the notch in the crankshaft 4 provided for the displacement unit 20, in particular in the guide area 18 of the crankshaft 4, a radial bearing 28 and a thrust bearing 29 are provided. As a result, the worm wheel 22 is pivotable about an axis that coincides with the thread axis of the thread 24, but is supported so as not to slide in the axial direction. Furthermore, the radial bearing 28 prevents the movement in the radial direction, but allows the rotation. For this purpose, the worm wheel 22 is provided with a suitable guide area 30 for the radial bearing 28 and a suitable guide area 31 for the thrust bearing 29. In order to insert the worm wheel 22 into each guide area 18, each guide area 18 is configured with a tapered notch. The tapered notch allows introduction of the worm wheel 22 from one side. The worm wheel 22 is fixed together with the bearings 28 and 29 by a nut 32 after being inserted.

  Further, the worm wheel 22 is provided with a toothed region 34. Since the toothed region 34 is located on the outer peripheral surface of the worm wheel 22 and is suitable for engaging with the worm 40 (not shown in FIG. 10), the displacement rotation movement of the worm 40 is the rotation movement. Introduced in.

  In FIGS. 8A and 8B, the crankshaft 4 including the guide region 18 and the inserted displacement unit 20 is shown in different perspective views including the screw 26.

  Further, the position and positioning of the worm 40 can be recognized from the cross section shown in FIGS. 5A and 5B in the longitudinal direction of the crankshaft 4. The worm 40 is inserted into a hollow chamber 41 formed as an axial hole. The hollow chamber 41 extends as a blind hole in the crankshaft 4 in the longitudinal direction, that is, the axial direction. In the present embodiment, the positions of the worm 40 and the worm wheel 22 are selected so that the toothed region 34 of the worm wheel 22 can mesh with the worm 40. The worm 40 itself is rotatably supported as a needle bearing 43 and is inserted into the hollow chamber 41, and the position in the axial direction is maintained by the thrust bearing 44.

  When it is desired to change the amount of eccentricity of the eccentric member 12 with respect to the rotational axis of the crankshaft 4, that is, when the rotational axis of the eccentric member 12 is to be moved relative to the rotational axis of the crankshaft 4, this is not shown. The worm 40 is rotated by an electric motor or other drive device. The worm 40 cannot move in the axial direction based on the fixation in the axial direction. The worm 40 engages with the worm wheel 22 housed in the guide area 18 of the crankshaft 4 of the displacement unit 20. The worm wheel 22 is similarly rotated by the rotation of the worm 40. Accordingly, the position of the displacement unit 20 is brought to the position of the eccentric body component member 12 by the thread engagement between the screw 26 fixed to the eccentric body component member 12 and the displacement unit 20 fixed to the crankshaft 4. It is relatively changed. Therefore, the stroke that can be transmitted to the coupling member 8 (see FIG. 1) is changed. This also changes the transmission ratio of the transmission 1. Due to the rotation of the worm 40 and the rotation of the worm wheel 22 accompanying the rotation of the worm 40, the worm wheel 22 moves along the axial direction of the screw 26, and consequently the displacement of the eccentric member 12 with respect to the crankshaft 4. Move in the direction.

  Since all the eccentric body units 12 provided on the crankshaft 4 are simultaneously equally displaced by the single worm 40 via the displacement device 20, a special device for synchronizing different displacements can be used for each eccentric. Not required for body component 12. Since the screw thread 26 is formed in a self-locking manner in relation to the female screw thread 24 of the worm 22, each of the eccentric body constituting members 12 is cranked even when the adjustment motor for rotating the worm 40 is not energized. It remains in the relative position of the eccentric member 12 with respect to the shaft 4. As a result, when it is not desired to change the transmission ratio of the transmission 1, continuous energization is not necessary. Furthermore, the overall distance between the worm 40 and the displacement between the crankshaft 4 and the eccentric body component 12 provides a very high transmission ratio, so that the electric motor can be used without an additional intermediary transmission. 40 can be driven directly. Furthermore, since the crankshaft 4 as a whole can have a relatively large cross section in the region of the guide region 18, the crankshaft 4 can be configured with a relatively high rigidity.

  DESCRIPTION OF SYMBOLS 1 Crank CVT transmission, 4 Crankshaft, 5 Driven shaft, 6 Eccentric body unit, 7 Free wheel unit, 8 Coupling member, 10 Apparatus for adjusting eccentricity, 12 Eccentric body component, 13, 14 Eccentric body Half of component, 15 screw, 17 rolling bearing, 18 guide area, 20 displacement unit, 22 worm wheel, 24 female thread, 26 screw, 27 extension, 28 radial bearing, 29 thrust bearing, 30 guide area, 31 radial bearing , 32 nut, 34 toothed area, 40 worm, 41 hollow chamber, 42 clamp body, 43 needle bearing, 44 thrust bearing, 45 outer ring, 47 pivoting area, 50 polygon contour

Claims (8)

In the device (10) for adjusting the amount of eccentricity of the rotational axis of the eccentric body constituting member (12) relative to the rotational axis of the crankshaft (4) of the crank CVT transmission (1),
A crankshaft (4) having at least one guide region (18) is provided for the eccentric member (12), and the outer peripheral surface of the eccentric member (12) is for fitting the rolling bearing (17). Suitable for
A worm (40), the crankshaft (4) has a hollow chamber (41) in the axial direction, the worm (40) is inserted into the hollow chamber (41) of the crankshaft (4),
Displacement provided in at least one guide region (18) to displace the eccentric member (12) in a direction perpendicular to the axial direction of the crankshaft (4) by the rotation of the worm (40). An apparatus for adjusting the amount of eccentricity of the rotational axis of the eccentric member constituting member relative to the rotational axis of the crankshaft of the crank CVT transmission, comprising a unit (20).   The eccentric member (12) is composed of two members, and the two members (13, 14) are connected to each other when assembled to the crankshaft (4). The device described.   3. The device according to claim 1, wherein the at least one guide area is arranged eccentrically with respect to the axis of the crankshaft.   The displacement unit (20) has a worm wheel (22) engaged with the worm (40), and the worm wheel (22) is stationary in the direction of adjusting the eccentricity, but the guide region (18). And is coupled to the eccentric member (12) via a screw device (24, 26), and the eccentric member (12) is disposed on the crankshaft (4). 4. The device according to claim 1, wherein the device is slidable relative to the guide area provided.   Device according to claim 4, characterized in that the screw device (24, 26) is constructed in a self-locking manner.   The screw device is configured as a female screw thread (24) formed on the worm wheel (22) and a male screw thread of a screw (26) supported so as not to rotate relative to the eccentric member (12). The device according to claim 4 or 5, characterized in that   A plurality of guide areas (18) and a plurality of eccentric body constituting members (12) are arranged along the axial direction of the crankshaft (4), and a plurality of guide areas (18) and a plurality of eccentric body constituting members (12) are arranged. 7) Device according to any one of the preceding claims, characterized in that it is moved by one common worm (40).   A device (10) for adjusting the amount of eccentricity of the rotational axis of the eccentric body constituting member (12) relative to the rotational axis of the crankshaft (4) according to any one of claims 1 to 7. Crank CVT transmission.

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