JP4318196B2 - Power transmission device for automobile - Google Patents

Description

[0001]
[Technical field to which the invention belongs]
The present invention comprises a propulsion shaft and a clutch device interposed between a driving means for traveling and a differential (differential), and this clutch device is a free end portion (protrusion) of the output shaft of the driving means or the input shaft of the differential. The present invention relates to a power transmission device in an automobile that is externally fitted to and supported by an end portion.
[0002]
[Prior art]
Conventionally, there is a power transmission device for an automobile described in Japanese Patent Laid-Open No. 10-71865.
[0003]
According to the above publication, the automobile includes a driving drive unit and a differential supported by a vehicle body, a propulsion shaft that enables the output shaft of the drive unit and the input shaft of the differential to be interlocked with each other, and the output shaft. Alternatively, a clutch device is provided between the free end portion of the input shaft and the propulsion shaft so as to connect and disconnect the power transmission between the free end portion and the propulsion shaft.
[0004]
A step portion is formed between the base portion and the midway portion so that the outer diameter dimension of the base portion of the free end portion is larger than that of the midway portion in the axial direction of the free end portion. A regulating body is attached to the protruding end. Then, the clutch device is externally fitted and supported so as to be slidable in the axial direction at the midway portion, and the step portion and the regulating body are extremely small in the axial direction of the clutch device (for example, (1 μm) is allowed to slide beyond a predetermined level while allowing sliding.
[0005]
In the above case, the step surface of the step portion extending from the middle portion side of the free end portion to the base portion side is a surface orthogonal to the axis of the free end portion, and the outer peripheral surface of the intermediate portion and the above The joint between the stepped portion and the stepped surface is formed to have orthogonal corners.
[0006]
As described above, the clutch device is allowed to slightly slide in the axial direction with respect to the free end portion. The reason for this is as follows.
[0007]
That is, the clutch device is externally fitted to the middle portion of the free end portion and is rotated with the free end portion in the axial direction. An outer member that is rotatable and interlocked with the propulsion shaft is provided, and power transmission between the inner member and the outer member can be freely connected and disconnected.
[0008]
In the above configuration, as a `` virtual technology '', a nut is screwed to the outermost end portion of the free end portion instead of the regulating body, and the inner members are integrally fastened to the stepped surface by the nut, Therefore, it is conceivable to fix each inner member of the clutch device to the free end so that it cannot slide in the axial direction with respect to the free end.
[0009]
However, if it does as mentioned above, since each said inner member is a long thing in the whole axial direction, these inner members are given the external force by fastening of the said nut, and a part of axial direction deform | transforms in radial direction. When this occurs, the center of gravity of the clutch device is deviated from the axial center of the free end portion in the radial direction, and the clutch device may vibrate when rotating together with the free end portion.
[0010]
Therefore, it is avoided that an external force in the axial direction is applied to the clutch device to fix the clutch device to the free end. As a result, as described above, the clutch device Slight sliding in the axial direction is allowed.
[0011]
When the vehicle is running, the clutch device is normally disengaged, and the driving force from the driving means is transmitted only to the front wheels. State.
[0012]
On the other hand, for example, when the front wheel enters the mud and runs idle while the vehicle is running, the clutch device is automatically connected, and in this case, the driving force from the driving means is The vehicle is transmitted to the front and rear wheels together, and the vehicle is brought into a front and rear four-wheel drive state, so that it is possible to escape from the muddy state.
[0013]
[Problems to be solved by the invention]
By the way, recently, it has been proposed that the clutch device includes a solenoid, and the clutch device is operated to be connected / disconnected by the on / off operation of the solenoid. It is larger than the addition of the solenoid and its peripheral devices.
[0014]
For this reason, when the above-described clutch device is supported by being externally fitted to the free end portion of the output shaft or the input shaft as in the prior art, a large weight of the clutch device is provided on the base side of the free end portion. A large moment is given based on.
[0015]
Therefore, a large stress tends to be concentrated at the joint portion formed so that the outer peripheral surface of the midway portion of the free end portion and the step surface are orthogonal to each other due to the large moment described above. Is not preferable because it reduces the life of the free end.
[0016]
In the above-mentioned “virtual technology”, the free end portion and each inner member of the clutch device are integrated with each other by fastening, so that the outer peripheral surface of the middle portion of the free end portion and the step surface of the step portion described above The joint portion is reinforced by each of the clutch devices, and stress concentration at the joint portion is suppressed.
[0017]
That is, the present application is based on the premise that there is a problem that the clutch device is allowed to slide in the axial direction with respect to the free end portion and stress concentration may occur in the joint portion of the free end portion. It becomes.
[0018]
The present invention has been made paying attention to the above situation, and a clutch device is externally fitted and supported on the free end portion of the output shaft of the driving means for driving or the input shaft of the differential. An object of the present invention is to further improve the life of the free end in a power transmission device in an automobile that is allowed to slide in the axial direction with respect to the free end.
[0019]
[Means for Solving the Problems]
The power transmission device for an automobile of the present invention for solving the above-described problems is as follows. In addition, the code | symbol attached | subjected to each term in this term does not limit and interpret the technical scope of this invention to the content of the term of the following "embodiment of invention".
[0020]
The invention of claim 1 includes a driving drive unit 8 and a differential 6 that are supported by the vehicle body 2, and a propulsion shaft 11 that enables the output shaft 20 of the drive unit 8 and the input shaft 17 of the differential 6 to be interlocked with each other. The clutch device 12 is interposed between the propulsion shaft 11 and the free end portion 21 of the output shaft 20 or the input shaft 17 and allows the power transmission between the free end portion 21 and the propulsion shaft 11 to be freely connected and disconnected. And a stepped portion 21c between the base portion 21a and the midway portion 21b so that the outer diameter dimension of the base portion 21a of the free end portion 21 is larger than that of the midway portion 21b in the axial direction of the free end portion 21. On the other hand, a restricting body 21d is attached to the protruding end portion of the free end portion 21, and the clutch device 12 is externally fitted and supported by the spline so as to be slidable in the axial direction on the midway portion 21b. Step part 21c A regulating member 21d is, in the power transmission device in a motor vehicle which is adapted to restrict the sliding above a predetermined while allowing very little sliding in the axial direction of the clutch device 12,
[0021]
The stepped portion 21c is tapered in the axial direction toward the intermediate portion 21b, and the end portion outer peripheral surface of the intermediate portion 21b on the stepped portion 21c side and the outer peripheral surface of the stepped portion 21c. The joining surface 46 is an arc concave surface, and the outer peripheral surface of the stepped portion 21c and the joining surface 46 are non-molded portions of the spline, and the outer peripheral surface of the stepped portion 21c and the joining surface 46 are externally fitted. The entire inner peripheral surface of the clutch device 12 can be a non-molded portion of the spline, and the entire inner peripheral surface of the clutch device 12 can be brought into surface contact with the outer peripheral surface of the stepped portion 21c and the joining surface 46. It is what.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0023]
1-3, the code | symbol 1 is a motor vehicle, The arrow Fr has shown the front of this motor vehicle 1. In FIG.
[0024]
A pair of left and right front wheels 3 and 3 are suspended by a suspension device at a front portion of a vehicle body 2 of the automobile 1, and a front differential 4 which is a front differential is interposed between the front wheels 3 and 3. A pair of left and right rear wheels 5 and 5 are suspended from the rear portion of the vehicle body 2 by a suspension device, and a rear differential 6 as a rear differential is interposed between the rear wheels 5 and 5. The front differential 4 and the rear differential 6 are respectively supported by the vehicle body 2 via the suspension device.
[0025]
Drive means 8 is provided which is supported by the front portion of the vehicle body 2 and can output a driving force for traveling. The driving means 8 includes an engine 9 supported on the front portion of the vehicle body 2 and a transfer 10 connected to the engine 9 via a transmission 9a. The engine 9 includes the transmission 9a and the transfer 10. The front wheels 3 are interlocked and connected via a front differential 4. The rear wheels 5 are linked to the engine 9 via a transmission 9 a, a transfer 10, a propulsion shaft 11, a clutch device 12, and a rear differential 6. That is, the automobile 1 is a front engine front drive (FF) car. 1 and 2 indicate the rotation direction of the propulsion shaft 11.
[0026]
The rear differential 6 includes a differential case 14 that is supported by the vehicle body 2, an input shaft 17 that is supported on the differential case 14 via a bearing 16 so as to be rotatable about an axial center 15 that extends in the front-rear direction, and the differential case 14. And a differential main body (not shown) that transmits the driving force from the engine 9 received in the internal space 18 and input to the input shaft 17 to the left and right rear wheels 5 and 5 with a predetermined torque distribution.
[0027]
The propulsion shaft 11 enables the output shaft 20 of the driving means 8 and the input shaft 17 of the rear differential 6 to be interlocked with each other. The input shaft 17 is supported on the differential case 14 by the bearing 16 as described above at one end side (rear side), and the other end side (front side) protrudes forward from the differential case 14. A free end 21 is provided.
[0028]
The clutch device 12 is interposed between the free end 21 of the input shaft 17 and the rear end of the propulsion shaft 11, and transmits power between the free end 21 of the input shaft 17 and the propulsion shaft 11. Can be freely connected and disconnected. That is, the clutch device 12 inputs the driving force from the engine 9 of the driving means 8 through the propulsion shaft 11 and transmits the driving force to the input shaft 17 of the rear differential 6 so as to be freely connected and disconnected.
[0029]
A step portion between the base portion 21a and the midway portion 21b so that the outer diameter dimension of the base portion 21a of the free end portion 21 of the input shaft 17 is larger than that of the midway portion 21b in the axial direction of the free end portion 21. 21c is formed. On the other hand, a restricting body 21d exemplified by a snap ring is detachably attached to the protruding end of the free end 21.
[0030]
The clutch device 12 is externally fitted by a spline so as to be slidable in the axial direction in the middle portion 21b of the free end portion 21 and supported by the middle portion 21b. In this case, the stepped portion 21c and the regulating body 21d regulate the sliding of the clutch device 12 beyond a predetermined amount while allowing a very slight sliding of the clutch device 12 in the axial direction.
[0031]
The clutch device 12 will be described in more detail. The clutch device 12 is disposed on the shaft 15 and is supported by a midway portion 21b of the free end portion 21 of the input shaft 17, and a pilot clutch 23. And a cam mechanism 24 for interlockingly connecting the main clutch 22 to the pilot clutch 23.
[0032]
The main clutch 22 constitutes an outer shell of the clutch device 12 and inputs a driving force from the engine 9 so as to be rotatable about the axis 15 so that a pair of front and rear is provided at the free end 21 of the input shaft 17. A clutch housing 27 supported by the bearings 25 and 26, a clutch plate 29 contained in the clutch housing 27 and rotating together with the clutch housing 27, and a spline at a midway portion 21b of the free end 21 of the input shaft 17. A cylindrical rotating body 28 which is externally fitted and rotated together with the input shaft 17, and is externally fitted to the rotating body 28 and rotated together with the rotating body 28 so that it can be frictionally joined to the clutch plate 29. Thus, a clutch plate 30 that rotates in conjunction with the clutch plate 29 is provided.
[0033]
The pilot clutch 23 includes a clutch plate 32 that rotates together with the clutch housing 27, and a clutch plate 33 that can be frictionally joined to the clutch plate 32 and rotate in conjunction with the clutch plate 32 by the joining. ing.
[0034]
The cam mechanism 24 includes a first cam member 34 that rotates together with the clutch plate 33 of the pilot clutch 23, a second cam member 35 that rotates together with the input shaft 17, and the second cam member 35 that serves as the first cam member. And a spherical cam follower 36 that is interlocked and connected to the cam 34 by cam engagement.
[0035]
The clutch device 12 rotates together with the clutch housing 27 and makes the armature 39 capable of being attracted and attracted by the armature 39 opposed to the clutch plates 32 and 33 of the pilot clutch 23 and the magnetic force generated by the input of current. A solenoid 40 that allows the armature 39 to be pressed against the clutch plates 32 and 33, and a support 43 that is located on the shaft 15 and is connected to the differential case 14 by a connector 42 and supports the solenoid 40, And a bearing 44 interposed between the clutch housing 27 and the support 43.
[0036]
In FIGS. 1 and 4, the stepped portion 21c is formed into a truncated cone shape in a taper shape toward the intermediate portion 21b almost in the axial direction, and is opposed to the stepped portion 21c in the axial direction. The inner peripheral surface of the end (rear end) of the rotating body 28 also has a tapered shape toward the midway portion 21b and has a truncated cone shape, and the outer peripheral surface of the stepped portion 21c and the rotating body 28 is in surface contact with the inner peripheral surface of the end portion.
[0037]
Further, the joint surface 46 between the end portion outer peripheral surface of the midway portion 21b on the stepped portion 21c side and the end portion outer peripheral surface of the stepped portion 21c on the midway portion 21b side is from the radially outer side. When viewed from the line of sight, the arcuate concave surface is formed. For this reason, the diameters of the end portions of the midway portion 21b and the stepped portion 21c facing each other are the same.
[0038]
In FIGS. 1 to 4, when the solenoid 40 is not in operation when the automobile 1 is running, the clutch device 12 is disengaged. For this reason, the driving force of the engine 9 is the transfer 10. The vehicle 1 is transmitted only to the left and right front wheels 3 via the front differential 4, and the vehicle 1 is brought into the front two-wheel drive state.
[0039]
On the other hand, when the solenoid 40 is operated by passing a current through the solenoid 40, the armature 39 is attracted by the magnetic force, and the armature 39 presses the clutch plates 32 and 33 of the pilot clutch 23. Friction-join each other. Then, the first cam member 34 of the cam mechanism 24 is rotated in conjunction with the clutch housing 27, and the first cam member 34 is displaced around the axis 15 with respect to the second cam member 35 ( Arrow A in FIG. 3, dashed line).
[0040]
Then, the cam follower 36 in which the second cam member 35 is cam-engaged with the first cam member 34 pushes the second cam member 35 with a large component force in the direction along the axis 15. (Arrow B in FIG. 3, two-dot chain line). Then, the second cam member 35 presses the clutch plates 32 and 33 of the main clutch 22 to frictionally join each other.
[0041]
That is, the clutch device 12 is connected and the driving force from the engine 9 is transmitted to the left and right rear wheels 5 and 5 via the clutch device 12 and the rear differential 6, thereby driving the front and rear four wheels. A state is obtained.
[0042]
In the above case, the current value flowing through the solenoid 40 is automatically adjustable based on the driving state of the automobile 1, and the clutch device 12 is adjusted by adjusting the magnetic force of the solenoid 40 by adjusting the current value. The amount of driving force transmitted from the engine 9 to the rear wheels 5 and 5 can be adjusted. And by this adjustment, the driving | running | working of the motor vehicle 1 by a desired four-wheel drive state is enabled.
[0043]
According to the said structure, the level | step-difference part 21c is made into the taper shape toward the said intermediate part 21b side in the axial direction, and the mutual joint surface 46 of the outer peripheral surface of the said intermediate part 21b and the outer peripheral surface of the said step part 21c. Is an arc concave surface.
[0044]
For this reason, since the joining surface 46 in which the outer peripheral surfaces of the midway part 21b and the stepped part 21c of the free end part 21 are joined to each other changes smoothly, the midway part 21b of the free end part 21 and the midway part 21b Compared to the conventional technique in which the joint portion between the step portion of the step portion extending from the side to the base portion 21a side and the step portion has an orthogonal corner, the joint surface 46 according to the above embodiment has a stress concentration. Occurrence is more reliably prevented.
[0045]
Therefore, in the automobile in which the clutch device 12 is externally fitted and supported on the free end portion 21 of the input shaft 17 of the rear differential 6 and the clutch device 12 is allowed to slide in the axial direction with respect to the free end portion 21. In the power transmission device, the life of the free end 21 is further improved.
[0046]
FIG. 5 shows the durability of the conventional technology in which the clutch device 12 is externally fitted to and supported by the free end portion 21 of the input shaft 17 of the rear differential 6 in the power transmission device, and that according to the above embodiment. The graph which contrasted the result of experiment is shown.
[0047]
When the three free end portions 21 according to the prior art and the two free end portions 21 according to the above embodiments are loaded so as to repeatedly apply substantially the same moments, As shown in FIG. 2, the free end 21 according to the conventional technique was all damaged by repeated loading of about 5 million times. However, as indicated by white circles in the figure, the free end portion 21 according to the above embodiment did not break even when the load was repeated 20 million times. Therefore, this experiment was stopped because no further experiment was necessary.
[0048]
That is, according to the experimental result, it can be seen that the life of the free end 21 according to the embodiment is significantly improved.
[0049]
2, a clutch device 12 is interposed between the free end portion 21 of the output shaft 20 of the driving means 8 and the propulsion shaft 11, and the clutch device 12 The power transmission between the free end portion 21 and the propulsion shaft 11 may be freely connected and disconnected. In this case, the output shaft 20 of the driving means 8 may have the same configuration as the input shaft 17 of the rear differential 6. The same effect as described above occurs.
[0050]
The automobile 1 may be a rear engine rear drive (RR) car or the like. In this case, the rear differential 6 may be replaced with a front differential 4.
[0051]
【The invention's effect】
The effects of the present invention are as follows.
[0052]
According to a first aspect of the present invention, there is provided a driving means and a differential for driving supported by the vehicle body, a propulsion shaft that enables the output shaft of the drive means and the input shaft of the differential to be interlocked with each other, A clutch device interposed between the free end portion and the propulsion shaft and capable of connecting / disconnecting power transmission between the free end portion and the propulsion shaft, the outer diameter of the base portion of the free end portion being A stepped portion is formed between the base portion and the midway portion so as to be larger than that of the midway portion in the axial direction of the free end portion, and a restricting body is attached to the protruding end portion of the free end portion, and the midway portion The clutch device is externally fitted and supported by a spline so as to be slidable in the axial direction, and the stepped portion and the regulating body allow the clutch device to slide very slightly in the axial direction. To regulate sliding beyond a predetermined level In the power transmission device in automobiles,
[0053]
The stepped portion has a taper shape in the axial direction toward the midway side, and the joint surface between the end outer peripheral surface of the midway portion on the stepped portion side and the outer peripheral surface of the stepped portion is an arc concave surface The outer peripheral surface and the joint surface of the stepped portion are made non-molded portions of the spline, and the inner peripheral surface of the portion of the clutch device that is externally fitted to the outer peripheral surface of the stepped portion and the joint surface The whole is formed as a non-molded portion of the spline, and the entire inner peripheral surface of the clutch device can be brought into surface contact with the outer peripheral surface and the joint surface of the stepped portion.
[0054]
For this reason, since the joining surface where each outer peripheral surface of the free end part and each outer peripheral surface of the step part joins smoothly changes, it extends from the mid part of the free end part to the base side from the mid part side. Compared to the conventional technique in which the joint portion between the step portion and the step surface has an orthogonal corner, it is more reliably prevented that stress concentration occurs on the joint surface according to the present invention. The
[0055]
Therefore, a clutch device is externally fitted to and supported by the free end portion of the output shaft of the drive means or the differential input shaft, and the clutch device is allowed to slide in the axial direction with respect to the free end portion. In this power transmission device, the life of the free end portion is further improved.
[Brief description of the drawings]
FIG. 1 is an enlarged cross-sectional view taken along line 1-1 in FIG.
FIG. 2 is an overall plan view of an automobile.
3 is an enlarged sectional view taken along line 3-3 in FIG.
FIG. 4 is a partially enlarged view of FIG. 1;
FIG. 5 is a graph showing experimental results.
[Explanation of symbols]
1 Car 2 Car body 5 Rear wheel 6 Rear differential
8 Driving means 11 Propulsion shaft 12 Clutch device 17 Input shaft 20 Output shaft 21 Free end portion 21a Base portion 21b Midway portion 21c Stepped portion 21d Restricting body 46 Joining surface

Claims (1)

Driving driving means and differentials supported by the vehicle body, a propulsion shaft capable of interlockingly connecting the output shaft of the driving means and the input shaft of the differential, the free end portion of the output shaft or the input shaft, and the propulsion shaft A clutch device interposed between the free end and the propulsion shaft, and the outer diameter of the base of the free end is in the axial direction of the free end. A stepped portion is formed between the base and the midway so as to be larger than that of the midway, while a restricting body is attached to the protruding end of the free end, and slides in the axial direction on the midway The clutch device is externally fitted and supported by a spline so that it can be freely moved, and the stepped portion and the regulating body slide more than a predetermined amount while allowing a very slight sliding of the clutch device in the axial direction. In automobiles that are supposed to regulate In a force transmission device,
The stepped portion is in its axial direction and tapered shape toward the middle portion, the end portion outer peripheral surface of the step portion side of the intermediate portion and, mutual bonding surface arc concave and the outer peripheral surface of the step portion The outer peripheral surface and the joint surface of the stepped portion are made non-molded portions of the spline, and the inner peripheral surface of the portion of the clutch device that is externally fitted to the outer peripheral surface of the stepped portion and the joint surface A power transmission device for an automobile in which the whole is a non-molded portion of the spline, and the entire inner peripheral surface of the clutch device can be brought into surface contact with the outer peripheral surface and the joint surface of the step portion.

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