JP2019143744A - Drive unit - Google Patents

Abstract

To provide a drive unit which can suppress the leakage of a lubricant from a mating face caused by a scatter of the lubricant.SOLUTION: A baffle plate 27 is arranged at a side face of a gear 16 which is accommodated in a main body case 10 in which a lubricant is stored, and partitions at least a clearance between a first case 12 and a second case 13 constituting the main body case 10 into a first region 28 being a region including a gear 16, and a second region 29 being a region not including the gear 16. The baffle plate 27 comprises a barrier part 32 in a position higher than an oil level height of the lubricant stored in the first region 28. The barrier part 32 is arranged between a part 26a of a mating face 26 of the first case 12 and the second case 13, and a portion 16a-1 of teeth 16a of the gear 16 opposing the part 26a, and blocks out a part of the lubricant which is scattered by the scoop-up of the gear 16 so as not to progress toward the part 26a of the mating face 26.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a drive device including a baffle plate in a main body case in which lubricating oil is stored.

  2. Description of the Related Art A transaxle in which a transmission and a differential gear are integrated is known as a vehicle drive device. As a differential gear lubrication system, so-called scooping lubrication is known in which lubricating oil is scooped up by a large-diameter ring gear to fly to each part. A baffle plate is provided in the differential case in order to control the flow of the lubricating oil by scraping lubrication or reduce the agitation resistance of the lubricating oil (for example, see Patent Document 1). The baffle plate includes a stirring unit that temporarily stores the lubricating oil stirred by the ring gear, and a storage unit that temporarily stores a part of the lubricating oil scraped up by the ring gear without returning to the stirring unit. It is a plate that partitions it. Therefore, a part of the lubricating oil wound up by the ring gear returns to the storage part and stays there, so that the oil level height (oil level height in a stationary state) in the stirring part is lowered, and accordingly the stirring resistance is reduced. Can be reduced.

  In scraping lubrication, lubricating oil attached to a rotating body such as a ring gear is carried to a high position by the rotating body and allowed to flow down to an appropriate location, and the lubricating oil is scattered to an appropriate location by centrifugal force generated by rotating with the rotating body. The lubrication is performed by distributing them. Therefore, it is not necessary to provide a special power source for lubrication, and a wide range of lubrication is possible. In addition, when supplying lubricating oil toward a specific lubrication location, the scattered lubrication is captured by an appropriate pocket provided inside the case of the drive device, and then from there to a specific lubrication location via an oil passage. Lube oil should be introduced.

Japanese Patent Application Laid-Open No. 2015-178887

  A rotating body such as a diff ring gear used for scraping lubrication is generally housed in a case in order to retain lubricating oil and shield it from external dust. In addition, the case is usually divided into structures because of the need for ease of assembly. In the case of the split structure, the diff ring gear itself has a large outer diameter, while the diff ring gear itself has a large outer diameter, and in the above-described transaxle, the outer diameter of the location where the diff ring gear is disposed. Alternatively, since the outer dimension becomes large, the split surface (matching surface) of the case is set on the outer peripheral side of the diff ring gear. Therefore, when the diff ring gear rotates, a part of the lubricating oil scooped up from the lower storage portion frequently scatters from the diff ring gear and collides with the mating surface. Normally, a sealing material is interposed between the mating surfaces to ensure liquid-tightness (oil-tightness), but the lubricating oil frequently collides with the mating surfaces and the diff ring gear rotates at high speed. In some cases, when the lubricating oil collides at a high speed, there is a possibility that the lubricating oil leaks or oozes out from the mating surfaces because the internal pressure of the case becomes high.

  The present invention has been conceived by paying attention to the above technical problem, and it is an object of the present invention to provide a drive device capable of suppressing leakage of lubricating oil from a mating surface due to scattering of lubricating oil. .

  In order to achieve the above object, according to the present invention, a gear and lubricating oil scraped up by the gear are contained in a main body case in which the first case and the second case are integrated by bringing their mating surfaces into contact with each other. The lubricating oil is divided into a first region in which the gear is accommodated and a second region in which the gear is not accommodated and is disposed on a side portion of the gear, and the oil level of the lubricating oil in the second region In the driving apparatus including the baffle plate that maintains the height higher than the oil level in the first region, at least a part of the mating surface is located on the outer peripheral side of the gear so as to face the gear, A portion of the mating surface between a portion of the gear that faces part of the mating surface and a portion of the mating surface and at a position that is higher than the oil level of the lubricating oil stored in the first region. The above Is characterized in that the barrier portion for shielding from the lubricating oil scattered from the Ya are provided integrally on said baffle plate.

  According to the present invention, the position of the mating surface is higher between the portion of the gear facing the part of the mating surface and the part of the mating surface and higher than the oil level of the lubricating oil stored in the first region. A barrier portion that shields part of the oil from the lubricating oil scattered from the gear is provided integrally with the baffle plate. For this reason, the lubricating oil flying at a position higher than the oil level height of the lubricating oil stored in the first region and between the part of the mating surface and the gear part can be blocked. For this reason, lubricating oil leakage from part of the mating surfaces can be suppressed.

It is sectional drawing which shows an example of the differential gear of this invention. It is a perspective view which shows a baffle plate. It is a top view which shows a guide member. It is sectional drawing which shows the guide member cut | disconnected along the AA line shown in FIG. It is sectional drawing which shows the guide member cut | disconnected along the BB line shown in FIG. It is an enlarged view which shows the guide member shown in FIG. It is a principal part perspective view which shows other embodiment of a barrier part. It is principal part sectional drawing which shows another embodiment of a barrier part. It is a principal part perspective view which shows another embodiment of a barrier part.

  Below, the drive device which is an example of this invention is demonstrated. The drive device is a device that is mounted on a vehicle and transmits the power of a driving force source such as an engine to the drive wheels. For example, the speed change function, the torque distribution function for the left and right drive wheels, and the differential of the left and right drive wheels are performed. The differential mechanism (differential gear) to be integrated may be configured as an integrated device.

  FIG. 1 is a cross-sectional view showing an example of a differential gear of the present invention. FIG. 1 shows the lower half from the axis 8 of the rotation axis of the drive shaft, and the lower half is not shown because it is substantially axially symmetric with the upper half. As shown in FIG. 1, the differential gear 9 is accommodated in an accommodation chamber 11 provided inside a differential case 10. The storage chamber 11 is formed in a sealed state by combining at least the first case 12 and the second case 13. A differential case 14 is stored in the storage chamber 11 in a state of being rotatably supported by a bearing 15. A ring gear 16 as an input gear is fixed to the differential case 14 with, for example, bolts. The ring gear 16 is the largest gear among the gears constituting the differential gear 9. Torque is transmitted to the ring gear 16 from, for example, a final output gear (not shown) of the transmission. The ring gear 16 may be a helical gear, for example. The differential case 10 is an example of a main body case in the embodiment of the present invention. The ring gear 16 is an example of a gear in the embodiment of the present invention.

  A pinion shaft 18 is held on the differential case 14, and a pinion gear 19 is rotatably held on the pinion shaft 18. The differential case 14 holds the left and right end portions of the first drive shaft 20 and the second drive shaft 21 in a rotatable manner. The first drive shaft 20 and the second drive shaft 21 are provided with left and right first side gears 23 and second side gears 24 so as to rotate integrally. The first side gear 23 and the second side gear 24 mesh with the pinion gear 19. Since the differential function itself of the differential gear 9 configured as described above is well known, detailed description thereof is omitted here.

  The first case 12 and the second case 13 may be high-pressure cast products made of, for example, an aluminum alloy. Since a draft angle is formed at the opening ends of the first case 12 and the second case 13, the mating surface (joint portion) 26 on the inner surfaces of the first case 12 and the second case 13 is centered on the axis 8. Projecting radially outward. The ring gear 16 is disposed below the accommodation chamber 11 in the vehicle height direction so that the teeth 16 a provided on the outer periphery face the inside of the mating surface 26. The ring gear 16 scrapes up the lubricating oil stored in the storage chamber 11 in the rotational direction (tangential direction) by rotating. The lubricating oil that has been scooped up flies upward of the storage chamber 11 and lubricates gear groups, bearings, and the like disposed in the storage chamber 11.

  A baffle plate 27 is provided between the ring gear 16 and the second case 13. The baffle plate 27 is a plate that divides a chamber for storing lubricating oil into a first region 28 and a second region 29 in a region below the axis 8 in the storage chamber 11, that is, a region below the gravity direction. The first region 28 is provided on the first case 12 side in the vehicle width direction across the baffle plate 27, and the second region 29 is provided on the second case 13 side. The ring gear 16 is disposed in the first region 28. A part of the ring gear 16 including at least the teeth 16 a is immersed in the lubricating oil stored in the first region 28. The baffle plate 27 is disposed on the side surface on the second case 13 side with respect to the differential case 14 and the ring gear 16 so as to cover a region below the differential case 14.

  As for the baffle plate 27, the outer periphery 27a in the area | region below the height direction of a vehicle is being fixed to the inner wall of the 2nd case 13 via the sealing member, for example. For this reason, the baffle plate 27 partitions a room for storing the lubricating oil into a first region 28 and a second region 29 in a region below the axis 8 in the storage chamber 11. The first region 28 and the second region 29 communicate with each other through a region above the axis 8, that is, the space above the baffle plate 27. The second region 29 stores part of the lubricating oil that has been scraped up and returned by the rotation of the ring gear 16.

  While the vehicle is traveling, the height of the first oil level L1 in the first region 28 is set to a position that is higher by a predetermined amount than the tooth 16a at the lowest position in the vehicle height direction (lowest position in the gravity direction). Yes. Further, the height of the first oil surface L1 in the first region 28 is set to be lower than the second oil surface L2 in the second region 29 in order to reduce the stirring resistance by the ring gear 16. That is, when the vehicle travels, the ring gear 16 rotates, and when the ring gear 16 rotates, the lubricating oil in the first region 28 is scooped up by the ring gear 16 and each gear disposed in the storage chamber 11 and its rotation support portion. Lubricate etc. A portion of the lubricating oil that has been scraped down falls to the second region 29 via the space above the first region 28. Thus, the lubricating oil moves from the first region 28 to the second region 29, and the height of the second oil surface L2 of the second region 29 is increased, while the first oil surface L1 of the first region 28 is increased. The height of becomes lower. By reducing the oil level height of the first region 28, the lubricating oil resistance when the ring gear 16 rotates is reduced.

  FIG. 2 is a perspective view showing a baffle plate. As shown in FIG. 2, the baffle plate 27 includes a main body portion 31 and a barrier portion 32. The main body 31 is disposed close to the side surface of the ring gear 16. The barrier portion 32 is disposed at a position higher than the first oil surface L1 of the lubricating oil stored in the first region 28, and bends toward the main body portion 31 between the mating surface 26 and the teeth 16a. Is provided. At least a portion 26 a of the mating surface 26 is located on the outer peripheral side of the gear 16 so as to face the gear 16. The barrier portion 32 is disposed between the portion 16 a-1 facing the portion 26 a of the mating surface 26 in the gear 16 and the portion 26 a of the mating surface 26.

  The barrier portion 32 has a substantially plate shape having a flat surface that covers a part of the teeth 16a, and a part of the lubricating oil that is caused to fly upward in the rotation direction of the ring gear 16 by scraping the ring gear 16 is a mating surface. Shield so as not to go to 26. The scattering direction is substantially tangential to the outer periphery of the gear 16. A part 26 a of the mating surface 26 is a portion located on an extension of a substantially tangent line on the outer periphery of the gear 16. The portion 16 a-1 of the gear 16 is a tooth facing the portion 26 a of the mating surface 26. Hereinafter, the part 26 a of the mating surface 26 may be simply referred to as the mating surface 26. Further, the portion 16a-1 of the gear 16 may be simply referred to as a tooth 16a.

  The barrier portion 32 may be provided integrally with the baffle plate 27 or may be provided separately. In the embodiment shown in FIG. 2 as an example, the barrier portion 32 is formed separately from the baffle plate 27. That is, the barrier portion 32 is provided integrally with the guide member 33 that is separate from the baffle plate 27. The guide member 33 includes a support portion 34 that supports the barrier portion 32 and fixes the barrier portion 32 to the main body portion 31. The main body 31 has an opening 36 for exposing the boss 35 protruding toward the second drive shaft so as to cover the differential case 14.

  The baffle plate 27 is fixed to the second case 13 by a fixture 38 such as a bolt inserted through a plurality of mounting holes formed in the main body 31. Some of the fixtures, for example, the fixture 38 a, may also be used as a fixture that fixes the guide member 33 that fixes the support portion 34 to the second case 13 to the main body portion 31. The support portion 34 has a positioning portion 39 for determining the posture of the guide member 33. The positioning portion 39 is formed by being bent at a predetermined angle with respect to the main body portion 31, and contacts the inclined surface portion 40 between the main body portion 31 and the boss portion 35 when attached to the main body portion 31. Then, the direction of the guide member 33 is determined to be a predetermined direction.

  FIG. 3 is a plan view showing the guide member. FIG. 3 is a view as seen from the second case 13 side in the vehicle width direction. As shown in FIG. 3, the barrier portion 32 has a receiving surface portion 42 that receives the lubricating oil flying in the direction of arrow C shown in FIG. The direction of arrow D shown in the figure indicates the direction of rotation of the ring gear 16. The direction of arrow C is the tangential direction of the outer periphery of the gear 16.

  FIG. 4 is a cross-sectional view showing the guide member cut along the line AA shown in FIG. As shown in FIG. 4, the receiving surface portion 42 is a surface facing the flying lubricating oil. That is, the receiving surface portion 42 is a gently curved surface so that the height along the height direction of the vehicle from the root 42a connected to the support portion 34 toward the farthest distal end 42b in the vehicle width direction gradually increases. . The receiving surface portion 42 is an inclined surface that flows toward the inner wall side of the second case 13 without staying after receiving the flying lubricant.

  FIG. 5 is a cross-sectional view showing the guide member cut along the line BB shown in FIG. As shown in FIG. 5, the receiving surface portion 42 receives the flying lubricating oil 5 a and then branches a part 5 b of the lubricating oil 5 a to the ring gear 16 side so that the entire lubricating oil 5 a does not face the mating surface 26. To suppress.

  FIG. 6 is an enlarged view showing the guide member shown in FIG. As shown in FIG. 6, when the ring gear 16 rotates in the direction of the arrow D, the lubricating oil stored in the first region 28 is scraped up, and the picked-up lubricating oil is ejected in the direction of the arrow E. . Part of the lubricant oil that has flown is abutted against the barrier portion 32 so as not to face the mating surface 26. That is, as described with reference to FIG. 4, the lubricating oil is guided in a direction not toward the mating surface 26 so that a part of the flying lubricating oil does not stay in the receiving surface portion 42. As a result, the discharged lubricating oil can be discharged better, and drag loss due to the ring gear 16 can be reduced. Further, as described with reference to FIG. 5, a part of the lubricating oil received by the receiving surface portion 42 is diverted to the ring gear 16 side so that the lubricating oil does not go to the mating surface 26. Thereby, the impact force of the lubricating oil applied to the sealing agent provided on the mating surface 26 can be suppressed.

  FIG. 7 is a main part perspective view showing another embodiment of the barrier part. The barrier portion 44 shown in FIG. 7 is formed in a box shape. That is, the barrier portion 44 is formed in a plate shape without the curved receiving surface portion 42 described in FIG. The thickness of the plate-like tip is such that the first surface portion 44a facing the flying lubricant oil is thinner than the second surface portion 44b on the opposite side. For this reason, the first surface portion 44a guides the flying lubricant oil to the third surface portion 44c that faces the ring gear 16 side, and guides the lubricant oil in a direction that does not face the mating surface 26. As a result, the impact on the sealing agent applied to the mating surface 26 is reduced, and the amount of lubricating oil to be guided in a direction not facing the mating surface 26 is increased. be able to.

  FIG. 8 is a cross-sectional view of an essential part showing another embodiment of the barrier part. As shown in FIG. 8, the barrier portion 46 has a receiving surface portion 47 formed on a linear slope instead of the curved receiving surface portion 42 described in FIG. Even if the receiving surface portion 47 is a straight slope, the same or similar effect as described with reference to FIG. 4 can be obtained.

  FIG. 9 is a main part perspective view showing still another embodiment of the barrier part. The guide member 50 shown in FIG. 9 is made by stamping a plate material. The barrier member 51 and the receiving surface portion 52 are provided separately so that the guide member 50 can be formed from a single plate material by bending. The barrier portion 51 is bent from the support portion 34 between the teeth 16a and the mating surface 26 with respect to a fold line 53 parallel to the height direction of the vehicle. Guide to the receiving surface 52 side. The receiving surface portion 52 is bent from the support portion 34 between the teeth 16a and the mating surface 26 with respect to a fold line 54 parallel to the front-rear direction of the vehicle. 2 Guide toward the case side. Note that the guide member 50 is not limited to being made by press molding using, for example, a metal plate, but may be made by die molding using a resin.

  Although the embodiments have been described above, the present invention is not limited to the embodiments, and appropriate modifications can be made within the scope of the claims. For example, the drive device is not limited to the differential gear 9. Further, the gear for scooping up the lubricating oil is not limited to the ring gear 16.

  DESCRIPTION OF SYMBOLS 9 ... Differential gear, 10 ... Differential case, 12 ... 1st case, 13 ... 2nd case, 16 ... Ring gear, Gear part 16a-1, 16a ... Teeth, 26 ... Mating surface, 26a ... A part of mating surface, 27 ... Baffle plate, 28 ... 1st area | region, 29 ... 2nd area | region, 32, 44, 46, 51 ... Barrier part.

Claims (1)

A gear and lubricating oil scraped up by the gear are accommodated in a main body case in which the first case and the second case are integrated by bringing the respective mating surfaces into contact with each other, and disposed on the side of the gear. And the oil level height of the lubricating oil in the second region is divided into a first region in which the gear is accommodated and a second region in which the gear is not accommodated. In the drive with a baffle plate that maintains higher than
At least a part of the mating surface is positioned on the outer peripheral side of the gear so as to face the gear;
One of the mating surfaces is positioned between a portion of the gear that faces a part of the mating surface and a part of the mating surface and higher than the oil level of the lubricating oil stored in the first region. A drive device characterized in that a barrier portion for shielding the portion from the lubricating oil scattered from the gear is provided integrally with the baffle plate.

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