JP2009138899A - Differential device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a differential device improved so as to restrain the occurrence of seizure and abnormal abrasion of a pinion bearing even in a state of lifting the vehicle body front side upward. <P>SOLUTION: An inside space of a differential case 1 is formed of a first space 20 and a second space 21 separated from the first space 20. A ring gear 2, a pinion gear 61 and the pinion bearing 3 on the pinion gear side are arranged in the first space 20, and first lubricating oil 5 is stored for lubricating the pinion bearing 3 on the pinion gear side, the ring gear 2 and the pinion gear 61. A pinion bearing 4 on the anti-pinion gear side is arranged in the second space 21, and second lubricating oil 8 is stored for lubricating the pinion bearing 4 on the anti-pinion gear side. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a differential device, and more particularly to a differential device that is less likely to cause seizure even when starting uphill.

  When the car turns a curve, there is a difference in the length of the trajectory through which the left and right wheels pass, so it is necessary to change the rotational speed of the left and right wheels. A differential device is mainly used in an automobile as a differential gear device for adjusting the rotational speed of the left and right wheels while applying the same torque to the left and right wheels. As a differential device, there is generally a system in which a differential gear mechanism is provided in a differential case together with lubricating oil, and the lubricating oil is scooped up by a ring gear and supplied to each part during operation. In such a differential device, it is most difficult and important to supply oil to a pinion bearing that is heavily loaded. Therefore, Patent Document 1 proposes a technique for reducing the rotational resistance of a ring gear or the like while ensuring the lubrication performance of the pinion bearing.

As shown in FIG. 3, in this type of differential device 200, the pinion shaft 206 is supported by two sets of a pinion bearing 203 and a pinion bearing 204. Above the pinion bearing 203 and the pinion bearing 204, there are provided a lubricating oil guide path 207 for guiding the lubricating oil 205 that has been lifted by the rotation of the ring gear 202, and two sets of outlet openings 272 of the lubricating oil guide path 207 are provided. The lubricating oil 205 is supplied to each of the upper portions of the two sets of bearings by providing the upper portions of the intermediate points of the bearings. Since this lubricating oil guide path 207 has a downward slope toward the two sets of bearings, it is lifted up from the lubricating oil reservoir 251 by the ring gear 202 and enters the lubricating oil guide path 207 from the inlet opening 271. The lubricating oil 205 is supplied to the upper side of the pinion shaft 206 that is the midpoint between the two sets of bearings along a gradient. A part of the supplied lubricating oil 205 is supplied to the upper portions of the two sets of pinion bearing 203 and pinion bearing 204 through the pinion shaft 206. Further, another part of the supplied lubricating oil 205 is transferred to the lower lubricating oil reservoir 252 and the lubricating oil reservoir 253 through the pinion shaft 206 and then supplied to the lower portions of the two sets of bearings. At the center of the lubricating oil reservoir, there is provided a protrusion 210 that protrudes upward from the lower part of the inner wall surface of the differential case 1 so that the lubricating oil 205 flows evenly through both the pinion bearing 203 and the pinion bearing 204.
JP 2006-161957 A

  By the way, an automobile does not always travel only on a substantially horizontal road surface. When the automobile travels uphill, as shown in FIG. 4, the vehicle body front side of the automobile is inclined to a state where it is lifted by the road surface inclination angle θ <b> 1, so that the differential device 200 also faces the vehicle body front side upward. The road surface is lifted by an inclination angle θ1. Therefore, the downward gradient of the lubricating oil guide path 207 is reduced, and the amount of the lubricating oil 205 supplied to a position on the pinion shaft 206 is insufficient, as well as being an intermediate point between the pinion bearing 203 and the pinion bearing 204. Further, a large amount of lubricating oil 205 to be supplied to the upper portions of the pinion bearing 203 and the pinion bearing 204 through the pinion shaft 206 is supplied to the pinion bearing 203 on the rear side of the vehicle body at a low position. Supply to the pinion bearing 204 becomes insufficient. Further, the lubricating oil reservoir 252 and the lubricating oil 205 dropped into the lubricating oil reservoir 253 are also supplied in a large amount to the lower part of the pinion bearing 203 on the rear side of the vehicle body, which is lower than the pinion bearing 204 on the front side of the vehicle body. Supply to the lower part of the pinion bearing 204 on the side becomes insufficient, causing seizure of the pinion bearing 204 on the front side of the vehicle body and abnormal wear, which becomes a problem. In particular, when the differential device 200 is started or when the outside air temperature is extremely low, the viscosity of the lubricating oil 205 is large and its fluidity is poor, so that the lubricating oil 205 is supplied to the pinion bearing 204 on the front side of the vehicle body. Becomes even more difficult. Further, when traveling downhill on the back, the rotation direction of the ring gear 202 is opposite to the rotation direction shown in FIG. Accordingly, the supply of the lubricating oil 205 to the pinion bearing 204 on the front side of the vehicle body is completely eliminated, and seizure of the pinion bearing 204 on the front side of the vehicle body and abnormal wear are likely to occur.

  The present invention has been made to solve such problems, and is improved so as to suppress the occurrence of seizure and abnormal wear of the pinion bearing on the front side of the vehicle body even when the front side of the vehicle body is lifted upward. It is an object of the present invention to provide a differential device.

  A differential device according to the present invention includes a pinion gear, and a pinion shaft that transmits power via the pinion gear, and rotatably supports the pinion shaft, and the pinion gear side and the anti-pinion in the axial direction of the pinion shaft A differential device includes a pinion bearing arranged side by side on a gear side, a ring gear meshed with the pinion gear, and a differential case in which the pinion shaft, the pinion bearing, the ring gear, and the pinion gear are provided. The space inside the differential case is provided with a ring gear, a pinion gear, and a pinion bearing on the pinion gear side, and a first space in which a first lubricating oil for lubricating the pinion bearing on the pinion gear side is stored. The second space is separated from the first space and is provided with a pinion bearing on the anti-pinion gear side, and contains a second lubricating oil for lubricating the pinion bearing on the anti-pinion gear side. Features.

  According to the above configuration, even when the differential case is inclined when traveling uphill, the lower portion of the pinion bearing on the pinion gear side is immersed in the first lubricating oil, and the first lubricating oil It will always be lubricated. Further, the lower part of the pinion bearing on the side opposite to the pinion gear is always lubricated by the second lubricating oil while being immersed in the second lubricating oil. As a result, seizure occurrence and abnormal wear at the lower part of the pinion bearing can be suppressed even on an uphill road, and seizure occurrence and abnormal occurrence at the lower part of the pinion bearing can be prevented even when traveling downhill on the back. Abrasion can be suppressed.

  The differential device according to the present invention partitions the first space and the second space, prevents the first lubricating oil from flowing out from the first space to the second space, and the second space. It is preferable to further include a seal member for preventing the lubricating oil from flowing out from the second space to the first space.

  According to the above configuration, even when the differential case is inclined, the second lubricating oil accommodated in the second space does not flow out from the second space to the first space by the seal member. As a result, it is possible to reliably prevent the second lubricating oil from flowing out and decreasing in the second space, and the lower part of the pinion bearing on the side opposite to the pinion gear is always lubricated by the second lubricating oil. The state can be reliably maintained. Further, since it is possible to prevent the second lubricating oil from flowing out into the first space and increasing the lubricating oil stored in the first space, it is possible to prevent an increase in the stirring resistance of the lubricating oil in the first space. can do. Therefore, the power loss caused by the stirring resistance is reduced, and the fuel efficiency can be improved. In addition, since the seal member can prevent the first lubricating oil containing the wear powder of the ring gear and the pinion gear from flowing out from the first space to the second space, the above-described conventional differential device can be prevented. Compared with the pinion bearing, the life of the pinion bearing provided in the second space is improved.

  ADVANTAGE OF THE INVENTION According to this invention, the differential apparatus improved so that generation | occurrence | production of the seizure of pinion bearing and abnormal wear might be suppressed also in the state where the vehicle body front side was lifted upwards can be provided.

Hereinafter, an embodiment of a differential device embodying the present invention will be described with reference to FIGS.
As shown in FIG. 1, the differential case 1 included in the differential device 100 according to the present embodiment has a vehicle body front side portion 12 having a substantially cylindrical shape having a central axis in the longitudinal direction of the vehicle body, and a vehicle body rear side portion 11. Is a substantially short cylindrical shape having a central axis in the left-right direction of the vehicle body.

  A substantially ring-shaped ring gear 2 is rotatably provided inside the vehicle body rear side portion 11 of the differential case 1. A pinion gear 61 is provided at the end of the pinion shaft 6 on the rear side of the vehicle body, and the pinion gear 61 is configured to mesh with the ring gear 2. The other end of the pinion shaft 6 protrudes from the vehicle body front side of the differential case 1 and is connected to a power side such as a propeller shaft (not shown).

  In addition, a pinion shaft 6 and pinion bearings 3 and 4 are provided inside the differential case 1. More specifically, a substantially annular pinion bearing 3 is fixed to the inner wall surface of the vehicle body front side portion 12 of the differential case 1 and in the vicinity of the end near the ring gear 2. A substantially annular pinion bearing 4 is fixed to the inner wall surface of the vehicle body front side portion 12 of the differential case 1 and to the vehicle body front side from the portion where the pinion bearing 3 is fixed. That is, in the axial direction of the pinion shaft 6, the pinion bearing 3 is provided on the pinion gear 61 side, and the pinion bearing 4 is provided on the anti-pinion gear side, and these pinion bearings 3 and 4 are connected to the shaft of the pinion shaft 6. It is juxtaposed in the direction. The pinion shaft 6 is rotatably supported by the two sets of the pinion bearing 3 and the pinion bearing 4. More specifically, the outer peripheral surface of the outer ring 31 constituting the pinion bearing 3 is fitted and fixed to the inner wall surface of the differential case 1, and a raceway surface is formed on the inner peripheral surface of the outer ring 31. On the other hand, the inner peripheral surface of the inner ring 32 constituting the pinion bearing 3 is fitted and fixed to the outer peripheral surface of the pinion shaft 6, and a raceway surface is formed on the outer peripheral surface of the inner ring 32. Further, a rolling element 33 is arranged so as to be able to roll in contact with the raceway surface of the outer ring 31 and the raceway surface of the inner ring 32. Similarly, the outer peripheral surface of the outer ring 41 constituting the pinion bearing 4 is fitted and fixed to the inner wall surface of the differential case 1, and a raceway surface is formed on the inner peripheral surface of the outer ring 41. On the other hand, the inner peripheral surface of the inner ring 42 constituting the pinion bearing 4 is fitted and fixed to the outer peripheral surface of the pinion shaft 6, and a raceway surface is formed on the outer peripheral surface of the inner ring 42. A rolling element 43 is arranged so as to be able to roll in contact with the raceway surface of the outer ring 41 and the raceway surface of the inner ring 42.

  In the present embodiment, as shown in FIG. 1, the space inside the differential case 1 is formed in the first space 20 formed in the vehicle body rear side portion 11 and the vehicle body front side portion 12. The second space 21 is configured.

  The first space 20 is provided with the ring gear 2, the pinion gear 61, and the pinion bearing 3 on the pinion gear 61 side, and the pinion bearing 3, the ring gear 2, and the pinion gear 61 on the pinion gear side are lubricated. A first lubricating oil 5 is stored. The lower part of the pinion bearing 3 is immersed in the first lubricating oil 5. Further, a lubricating oil reservoir 51 is provided in the lower portion of the first space 20, and the first lubricating oil 5 is accumulated therein. Therefore, the lower part of the ring gear 2 is in contact with the first lubricating oil 5.

  The second space 21 is provided with a pinion bearing 4 on the side opposite to the pinion gear, and stores a second lubricating oil 8 that lubricates the pinion bearing 4 on the side opposite to the pinion gear. The lower part of the pinion bearing 4 is in a state of being immersed in the second lubricating oil 8. Lubricating oil reservoirs 52 and 53 are formed below the second space 21, and the second lubricating oil 8 is stored therein. The second space 21 is separated from the first space 20, and the first space 20 is separated from the first space 20 by a seal member 22 provided in a portion where the pinion shaft 6 penetrates the pinion bearing 3 on the pinion gear side. The second space 21 is partitioned.

  Supply of lubricating oil to the pinion bearing 3 and the pinion bearing 4 in the differential device 100 according to the present embodiment is performed as follows. The power transmitted from the engine (not shown) of the vehicle to which the differential device 100 is attached to the pinion shaft 6 via the propeller shaft (not shown) or the like rotates the ring gear 2 via the pinion gear 61. Then, as the ring gear 2 rotates, the first lubricating oil 5 housed in the first space 20 and in contact with the ring gear 2 is lifted up, and one of the first lubricating oil 5 lifted up The portion is guided to the upper part of the pinion bearing 3, and the upper part of the pinion bearing 3 is lubricated by the first lubricating oil 5. Further, since the lower part of the pinion bearing 3 is maintained in a state immersed in the first lubricating oil 5, the lower part of the pinion bearing 3 is lubricated by the first lubricating oil 5.

  In the second space 21, the second lubricating oil 8 accommodated in the second space 21 is scooped up and swung up with the rotation of the pinion shaft 6 and the pinion bearing 4. A part of the lubricating oil 8 is guided to the upper part of the pinion bearing 4, and the upper part of the pinion bearing 4 is lubricated by the second lubricating oil 8. Further, since the lower part of the pinion bearing 4 is maintained in a state immersed in the second lubricating oil 8, the lower part of the pinion bearing 4 is lubricated by the second lubricating oil 8.

  Next, the supply of lubricating oil to the pinion bearing 3 and the pinion bearing 4 when the vehicle using the differential device 100 according to the present embodiment starts on an uphill slope will be described with reference to FIG. In addition, since the basic principle of supply of lubricating oil is as above-mentioned, the overlapping description is abbreviate | omitted here.

  As shown in FIG. 2, when the inclination angle of the road surface on the uphill road with respect to the horizontal plane 80 is θ1, the differential device 100 is also lifted from the vehicle body front side by the inclination angle θ1 with respect to the horizontal plane. Even in a state where the front side of the vehicle body is lifted upward and the differential case 1 is inclined, in the first space 20, the first lubrication that is in contact with the ring gear 2 is caused by the rotation of the ring gear 2. The oil 5 is pumped up, and a part of the first lubricating oil 5 thus pumped up is guided to the upper part of the pinion bearing 3, and the upper part of the pinion bearing 3 is lubricated by the first lubricating oil 5. Further, as shown in FIG. 2, the lower part of the pinion bearing 3 is maintained in a state immersed in the first lubricating oil 5, so that the lower part of the pinion bearing 3 is lubricated by the first lubricating oil 5. Is maintained.

  Even in a state where the front side of the vehicle body is lifted upward and the differential case 1 is inclined, the second space 21 accommodated in the second space 21 is rotated in the second space 21 as the pinion shaft 6 rotates. The lubricating oil 8 is lifted up, and a part of the second lubricating oil 8 that has been lifted up is guided to the upper part of the pinion bearing 4, and the upper part of the pinion bearing 4 is lubricated by the second lubricating oil 8. . Further, as shown in FIG. 2, the lower part of the pinion bearing 4 is maintained in a state where it is immersed in the second lubricating oil 8, so that the lower part of the pinion bearing 4 is lubricated by the second lubricating oil 8. Is maintained.

  Note that the amount of the first lubricating oil 5 stored in the first space 20 is such that the state where the lower part of the pinion bearing 3 is immersed in the first lubricating oil 5 can be maintained when the differential case 1 is inclined. The amount is not particularly limited. Similarly, the amount of the second lubricating oil 8 stored in the second space 21 is such that the lower part of the pinion bearing 4 is immersed in the second lubricating oil 8 when the differential case 1 is inclined. The amount is not particularly limited as long as it can be maintained.

  In addition, as described above, the first space 20 and the second space 21 are separated, and the first space 20 and the second space 21 are partitioned by the seal member 22, The first lubricating oil 5 and the second lubricating oil 8 do not mix. Accordingly, even when the differential case 1 is inclined, the second lubricating oil 8 accommodated in the second space 21 does not flow out from the second space 21 to the first space 20 by the seal member 22. . Therefore, it is possible to reliably prevent the second lubricating oil 8 from flowing out and reducing the second lubricating oil 8 in the second space 21. In addition, since it is possible to prevent the second lubricating oil 8 from flowing out into the first space and increasing the amount of lubricating oil stored in the first space 20, the stirring resistance of the lubricating oil in the first space 20 can be reduced. An increase can be prevented.

  When the uphill traveling is finished and the traveling is made on a flat road surface, the state where the differential device 100 is lifted to the front side of the vehicle body by the inclination angle θ1 with respect to the horizontal plane is released, and the differential device 100 is shown in FIG. Return to the state shown. At this time, the first lubricating oil 5 accommodated in the first space 20 does not flow out from the first space 20 to the second space 21 by the seal member 22. That is, the first lubricating oil 5 accommodated in the first space contains the wear powder of the ring gear 2 and the pinion gear 61. The first lubricating oil 5 containing this wear powder, Outflow from the first space 20 to the second space 21 is prevented.

According to the differential device 100 of the above embodiment, the following effects can be obtained.
(1) In the differential device 100 according to the above-described embodiment, the space inside the differential case 1 is provided with the ring gear 2, the pinion gear 61, and the pinion bearing 3 on the pinion gear side, and the first device that lubricates the pinion bearing 3 is provided. A first space 20 in which the lubricating oil 5 is stored and a second pinion bearing 4 separated from the first space 20 and provided with an anti-pinion gear side pinion bearing 4 are provided to lubricate the anti-pinion gear side pinion bearing 4. Is formed by the second space 21 in which the lubricating oil 8 is stored. Therefore, even when the vehicle body front side is lifted upward and the differential case 1 is tilted when traveling uphill, the lower part of the pinion bearing 3 is immersed in the first lubricating oil 5, 1 is always lubricated by the lubricating oil 5. Further, the lower part of the pinion bearing 4 is always lubricated by the second lubricating oil 8 in a state immersed in the second lubricating oil 8. As a result, it is possible to suppress the occurrence of seizure and abnormal wear in the lower portions of the pinion bearings 3 and 4 even on an uphill road. Similarly, even when traveling downhill on the back, it is possible to suppress the occurrence of seizure and abnormal wear in the lower portions of the pinion bearings 3 and 4.

  (2) In the differential device 100 of the above embodiment, the first space 20 and the second space 21 are partitioned, and the second lubricating oil 8 flows out from the second space 21 to the first space 20. A sealing member 22 is provided for preventing the occurrence of the failure. Accordingly, even when the differential case 1 is inclined, the second lubricating oil 8 accommodated in the second space 21 does not flow out from the second space 21 to the first space 20 by the seal member 22. . As a result, it is possible to reliably prevent the second lubricating oil 8 from flowing out and reducing the second lubricating oil 8 in the second space 21, so that the lower portion of the pinion bearing 4 is in the second lubrication. The state always lubricated by the oil 8 can be reliably maintained. In addition, since it is possible to prevent the second lubricating oil 8 from flowing out into the first space and increasing the amount of lubricating oil stored in the first space 20, the stirring resistance of the lubricating oil in the first space 20 can be reduced. An increase can be prevented. Therefore, the power loss caused by the stirring resistance is reduced, and the fuel efficiency can be improved. Further, the seal member 22 can prevent the first lubricating oil 5 containing the abrasion powder of the ring gear 2 and the pinion gear 61 from flowing out from the first space 20 to the second space 21. Compared with the pinion bearing 204 of the conventional differential device 200, the life of the pinion bearing 4 provided in the second space 21 is improved.

In addition, you may change the said embodiment as follows.
In the above embodiment, the lubricating oil reservoirs 52 and 53 are formed in the lower portion of the second space 21, but a configuration without the lubricating oil reservoirs 52 and 53 may be used. Even when the differential case 1 is tilted, the lubricating oil reservoirs 52 and 53 need to be specially provided if the lower part of the pinion bearing 4 can be maintained in a state where it is immersed in the second lubricating oil 8. There is no.

  In the above embodiment, the rolling element 33 and the rolling element 43 are tapered rollers, and the pinion bearing 3 and the pinion bearing 4 are tapered roller bearings, but other configurations may be used. For example, at least one of the rolling element 33 and the rolling element 43 may be a ball, and at least one of the pinion bearing 3 and the pinion bearing 4 may be a ball bearing.

  The differential device according to the present invention is a differential device improved so as to suppress the occurrence of seizure of pinion bearings and abnormal wear even in a state where the front side of the vehicle body is lifted upward. Can be widely installed.

It is drawing explaining one Embodiment of the differential apparatus to which this invention is applied, Comprising: It is sectional drawing of the up-down direction which passes along the central axis of a pinion axis | shaft. FIG. 2 is a cross-sectional view showing a state in which the vehicle body front side of the differential device shown in FIG. 1 is pulled upward at an inclination angle θ1. It is drawing explaining one Embodiment of the conventional differential apparatus, Comprising: It is sectional drawing of the up-down direction which passes along the central axis of a pinion axis | shaft. FIG. 4 is a cross-sectional view in which the vehicle body front side of the differential device shown in FIG.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Differential case, 2 ... Ring gear, 3 ... Pinion bearing (pinion gear side pinion bearing), 4 ... Pinion bearing (anti-pinion gear side pinion bearing), 5 ... First lubricating oil, 6 ... Pinion shaft, DESCRIPTION OF SYMBOLS 8 ... 2nd lubricating oil, 11 ... Vehicle body rear side part of differential case, 12 ... Vehicle body front side part of differential case, 20 ... 1st space, 21 ... 2nd space, 22 ... Seal member, 31 ... Outer ring, 32 ... inner ring, 33 ... rolling element, 41 ... outer ring, 42 ... inner ring, 43 ... rolling element, 51 ... lubricating oil reservoir, 52 ... lubricating oil reservoir, 53 ... lubricating oil reservoir, 61 ... pinion gear, 80 ... horizontal plane , Θ1: inclination angle with respect to the horizontal plane

Claims (2)

A pinion shaft provided with a pinion gear and transmitting power through the pinion gear;
A pinion bearing that rotatably supports the pinion shaft, and is arranged in parallel on the pinion gear side and the anti-pinion gear side in the axial direction of the pinion shaft;
A ring gear meshed with the pinion gear;
In a differential device comprising the pinion shaft, the pinion bearing, the ring gear, and a differential case in which the pinion gear is provided,
The space inside the differential case is provided with the ring gear, the pinion gear, and the pinion bearing on the pinion gear side, and contains the first lubricating oil that lubricates the pinion bearing on the pinion gear side The first space is separated from the first space, the pinion bearing on the anti-pinion gear side is provided, and a second lubricating oil that lubricates the pinion bearing on the anti-pinion gear side is stored. A differential device comprising the second space.   The first space and the second space are partitioned to prevent the first lubricating oil from flowing out from the first space to the second space, and the second lubricating oil 2. The differential device according to claim 1, further comprising a seal member for preventing the second gas from flowing out from the second space to the first space.

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