JP2010007699A - Differential device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a differential device capable of reliably feeding lubricating oil to a sliding part between a driving shaft and a supporting part of a differential case. <P>SOLUTION: The differential device 1 comprises a differential case 3 which is rotatably stored in a carrier 2 with lubricating oil sealed therein, and a ring gear 4 being fixed thereto, a pair of side gears 5, 7 which are stored in the differential case 3 in a relatively rotatable manner, a pinion 9 to be engaged with the pair of side gears 5, 7, and a driving shaft connected to the pair of side gears 5, 7. Hollow insertion parts 13, 15 with the driving shaft being inserted on both end sides in the axial direction are formed in the differential case 3. Sliding supports 17, 19 for slidably supporting the driving shaft are provided on inner circumferences of the insertion parts 13, 15. Feed passages 21, 23 which communicate the sliding supports 17, 19 and the outer circumferential sides of the insertion parts 13, 15 to feed the scraped lubricating oil to the ring gear 4 by the rotation of the differential case 3 are formed in the insertion parts 13, 15. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a differential device applied to a vehicle.

  Conventionally, as a differential device, a parallel shaft type differential device and a bevel gear type differential device are known. In such a differential device, various proposals have been made to introduce lubricating oil that is swung up by a ring gear fixed to the differential case so as to be integrally rotatable (see, for example, Patent Documents 1 to 3).

  For example, in the differential device of Patent Document 1, a recess is provided on the outer periphery of the differential case to collect the lubricating oil scooped up by the ring gear, and a through hole is provided in the differential case to connect the recess and the inside of the differential case. It is easy to introduce lubricating oil. Further, in the differential device of Patent Document 2, in addition to the structure of Patent Document 1, a lubricating oil receiving rib is provided so that the lubricant collected in the recesses by rotation of the differential case is not scattered outside the differential case, and the rotation of the differential case is performed. Even at times, the lubricating oil can be sufficiently introduced into the differential case.

  However, in the differential devices of Patent Documents 1 and 2, the lubricating oil can be supplied to the gear meshing portion of the differential gear set housed in the differential case and the sliding portion of the differential case and the differential gear set. The lubricating oil cannot be sufficiently supplied to the sliding portion between the drive shaft that is inserted into the differential case and connected to the differential gear set and the support portion of the differential case that supports the drive shaft.

Therefore, in the differential device of Patent Document 3, a flow path is provided on the axially outer side of the sliding portion between the drive shaft and the support portion of the differential case, and the lubricating oil is allowed to flow into the inside of the differential case from the flow path to slide the sliding portion. Is lubricated.
JP-A-8-270764 Japanese Utility Model Publication No. 5-83526 Japanese Patent Laid-Open No. 2007-232118

  However, in recent years, the lubricating oil sealed in the carrier that accommodates the differential case has been decreasing due to a reduction in stirring resistance due to the lubricating oil, cost reduction, and the like. For this reason, if a flow path is provided outside in the axial direction of the sliding portion between the drive shaft and the support portion of the differential case as in Patent Document 3, the distance from the ring gear increases and the ring gear is scraped up. There was a possibility that the lubricating oil could not reach the flow path sufficiently.

  Therefore, an object of the present invention is to provide a differential device that can reliably supply lubricating oil to a sliding portion between a drive shaft and a support portion of a differential case.

  According to the first aspect of the present invention, a differential case in which a ring gear is fixed and rotatably accommodated in a carrier in which lubricating oil is sealed, a pair of side gears accommodated in the differential case so as to be relatively rotatable, and the pair of side gears mesh with each other. A pinion that allows differential rotation of the pair of side gears and that is rotationally driven integrally with the differential case in the rotation direction of the differential case; and a drive shaft that is inserted into the differential case and connected to the pair of side gears. A differential device, wherein the differential case is provided with a hollow insertion portion through which the drive shaft is inserted at both ends in the axial direction, and the inner periphery of the insertion portion is slidably supported by the drive shaft. A sliding support portion is provided, and the insertion portion communicates with the sliding support portion and an outer peripheral side of the insertion portion to rotate the differential case. Wherein the supply path in which the lubricating oil scooped up to the ring gear is supplied is provided.

  Invention of Claim 2 is a differential apparatus of Claim 1, Comprising: The said supply path is provided in the inside of the said differential case of the axial direction of the said insertion part, The outer periphery of the said sliding support part and the said drive shaft A guide path that guides the lubricating oil supplied from the supply path to the outside of the differential case in the axial direction is provided in any one of the portions where the sliding support portion is located. To do.

  A third aspect of the present invention is the differential apparatus according to the first or second aspect, wherein the insertion portion is provided with a large-diameter portion having an inner diameter larger than the sliding support portion on the inner side of the differential case in the axial direction. It is characterized by being.

  A fourth aspect of the present invention is the differential apparatus according to the third aspect, wherein the drive shaft is provided with a small-diameter portion having an inner diameter smaller than the sliding support portion, and the small-diameter portion and the large-diameter portion A lubricating oil reservoir for storing the lubricating oil is provided between them.

  A fifth aspect of the present invention is the differential apparatus according to any one of the first to fourth aspects, wherein the fixed portion to which the ring gear of the differential case is fixed is directed from the outer diameter side toward the inner diameter side. A plurality of ribs inclined so as to gradually increase in thickness are provided, and the supply path is located in the vicinity of the end portion on the inner diameter side of the rib.

  The differential device according to claim 1 is provided with a sliding support portion that slides and supports the drive shaft on the inner periphery of the insertion portion through which the drive shaft of the differential case is inserted, and the insertion portion includes a sliding support portion and an insertion portion. Since the supply path for supplying the lubricating oil scraped up by the ring gear by the rotation of the differential case is provided in communication with the outer peripheral side, the lubricating oil can be directly supplied to the sliding support portion.

  Therefore, the lubricating oil can be reliably supplied to the sliding portion between the drive shaft and the support portion of the differential case.

  The differential apparatus according to claim 2, wherein the supply path is provided on the inside of the differential case in the axial direction of the insertion portion, and the supply path is provided in one of the sliding support portion and a portion where the sliding support portion on the outer periphery of the drive shaft is located. Since the guide path for guiding the lubricant supplied from the outside to the outside of the differential case in the axial direction is provided, the lubricant introduced from the supply path can be reliably supplied to the outside in the axial direction inside the differential case.

  In the differential device according to the third aspect, since the insertion portion is provided with a large-diameter portion having an inner diameter larger than that of the sliding support portion on the inner side of the differential case in the axial direction, the lubricating oil introduced from the supply path is supplied to the large-diameter portion. In addition to facilitating distribution, the lubricating oil can be provided with a centrifugal pump function to facilitate introduction of the lubricating oil into the differential case.

  In the differential device according to the fourth aspect, the drive shaft is provided with a small-diameter portion having an inner diameter smaller than that of the sliding support portion, and a lubricating oil reservoir for collecting lubricating oil is provided between the small-diameter portion and the large-diameter portion. It is possible to prevent the lubricating oil introduced into the differential case from being exhausted.

  The differential device according to claim 5 is provided with a plurality of ribs inclined so as to gradually increase in thickness from the outer diameter side toward the inner diameter side in the fixed portion to which the ring gear of the differential case is fixed, and the supply path has an inner diameter of the rib Therefore, it is possible to easily introduce the lubricating oil scraped up by the ring gear into the supply path via the rib.

  A differential apparatus according to an embodiment of the present invention will be described with reference to FIGS.

  The differential device 1 of the present embodiment includes a carrier 2 in which lubricating oil is enclosed, a differential case 3 rotatably accommodated in the carrier 2 and a ring gear 4 fixed thereto, and a relative rotation accommodated in the differential case 3. A pair of side gears 5, 7, and a pinion 9 that meshes with the pair of side gears 5, 7 and that allows differential rotation of the pair of side gears 5, 7 and that is rotationally driven integrally with the differential case 3 in the rotational direction of the differential case 3; The drive shaft 11 is inserted into the differential case 3 and connected to the pair of side gears 5 and 7 (only one drive shaft is shown, but the same drive shaft is also connected to the side gear 7). The differential case 3 is provided with hollow insertion portions 13 and 15 through which the drive shaft 11 is inserted at both end sides in the axial direction, and the inner periphery of the insertion portions 13 and 15 slides with the drive shaft 11. Sliding support portions 17 and 19 are provided. The insertion portions 13 and 15 communicate with the sliding support portions 17 and 19 and the outer peripheral side of the insertion portions 13 and 15, and the ring gear 4 is rotated by the rotation of the differential case 3. Supply paths 21 and 23 are provided to which the lubricating oil scraped up is supplied.

  Further, the supply paths 21 and 23 are provided in an intermediate portion on the inner side of the differential case 3 in the axial direction of the insertion portions 13 and 15, and supply portions are provided in portions where the slide support portions 17 and 19 on the outer periphery of the drive shaft 11 are located. A spiral groove 25 is provided as a guide path for guiding the lubricating oil supplied from the paths 21 and 23 to the outside of the differential case 3 in the axial direction.

  Further, the insertion portions 13 and 15 are provided with large diameter portions 27 and 29 having an inner diameter larger than that of the sliding support portions 17 and 19 on the inner side of the differential case 3 in the axial direction. The large diameter portions 27 and 29 are provided at positions on the inner side in the axial direction with respect to the supply paths 21 and 23 communicating with the sliding support portions 17 and 19.

  Further, the drive shaft 11 is provided with a small-diameter portion 31 having an inner diameter smaller than that of the sliding support portions 17 and 19, and a lubricating oil reservoir 33 that collects lubricating oil between the small-diameter portion 31 and the large-diameter portions 27 and 29. Is provided.

  Further, a flange portion 35 as a fixed portion to which the ring gear 4 of the differential case 3 is fixed is provided with a plurality of ribs 37 inclined so as to gradually increase in thickness from the outer diameter side toward the inner diameter side. 21 is provided in the vicinity of the end on the inner diameter side of the rib 37, and is located at the inner diameter side tip of the rib 37 in this embodiment.

  As shown in FIGS. 1 to 7, the differential case 3 includes a case main body 39 and a cover member 41. The case main body 39 and the cover member 41 are provided with hollow insertion portions 13 and 15 through which the drive shaft 11 is inserted at both ends in the axial direction. The outer periphery of the insertion portions 13 and 15 is supported by a bearing (not shown), so that the differential case 3 is rotatably accommodated and supported by the carrier 2 in which lubricating oil is enclosed. The case main body 39 and the cover member 41 are formed with a flange portion 35, the ring gear 4 is fixed to the flange portion 35, and the case main body 39 and the cover member 41 are integrally fixed by a bolt 43. . The differential case 3 accommodates a pinion shaft 45, a pinion 9, and a pair of side gears 5, 7, and a drive shaft 11 is inserted and connected to the pair of side gears 5, 7.

  An end of the pinion shaft 45 engages with the differential case 3 and is prevented from being detached by a pin 47, and the pinion 9 that is supported by being rotated integrally with the differential case 3 is revolved. The pinion 9 transmits a driving force to the pair of side gears 5 and 7 and is rotatably supported on the pinion shaft 45 so as to be driven to rotate when a differential rotation occurs between the pair of meshing side gears 5 and 7. . A spherical washer 49 is disposed between the pinion 9 and the differential case 3.

  The pair of side gears 5 and 7 are supported by the differential case 3 on the outer periphery of the boss portions 51 and 53 so as to be relatively rotatable. Further, the drive shaft 11 is splined to the inner circumference of the boss portions 51 and 53 so as to be integrally rotatable with the pair of side gears 5 and 7. Thrust washers 55 and 57 are disposed between the back side of the pair of side gears 5 and 7 and the differential case 3.

  The drive shaft 11 is inserted into the inner periphery of the insertion portions 13 and 15 of the differential case 3 and is slidably supported by the sliding support portions 17 and 19 of the insertion portions 13 and 15, and one end side in the axial direction is a pair of side gears. 5 and 7 are connected. Moreover, the shaft member (not shown) which contact | abuts the axial direction end surface of the insertion parts 13 and 15 and is connected with the wheel on either side in the axial direction other end side of the drive shaft 11 is bolted through a constant velocity joint etc. The fixed portion 59 is integrally provided.

  In such a drive shaft 11, since the fixing portion 59 of the drive shaft 11 is in contact with the axial end surfaces of the insertion portions 13 and 15, it is difficult to introduce lubricating oil into the inside of the differential case 3 from this portion. It was difficult to sufficiently lubricate the moving support portions 17 and 19. Although it is conceivable to provide a lubricating oil supply path at the axial ends of the insertion parts 13 and 15, as described above, since the lubricating oil tends to decrease, the lubricating oil is supplied to the axial end supply path. It was difficult to introduce. Therefore, in the differential device 1, the lubricating oil can be reliably supplied to the sliding support portions 17 and 19 of the differential case 3.

  The insertion portions 13 and 15 of the differential case 3 are provided with supply paths 21 and 23 that communicate the sliding support portions 17 and 19 with the outer peripheral sides of the insertion portions 13 and 15. Lubricating oil scraped up by the ring gear 4 by the rotation of the differential case 3 is supplied to the supply paths 21 and 23. Further, a double threaded spiral groove 25 is provided in a portion where the sliding support portions 17 and 19 of the drive shaft 11 are located. The spiral groove 25 is provided so as to guide the lubricating oil supplied from the supply paths 21 and 23 to the outside of the differential case 3 in the axial direction. Large diameter portions 27 and 29 having an inner diameter larger than that of the sliding support portions 17 and 19 are provided inside the differential case 3 in the axial direction of the insertion portions 13 and 15. Further, the drive shaft 11 is provided with a small diameter portion 31 having an inner diameter smaller than that of the sliding support portions 17 and 19. Between the small-diameter portion 31 of the drive shaft 11 and the large-diameter portion 27 of the insertion portion 13, a lubricating oil reservoir 33 that stores lubricating oil is provided. A lubricating oil reservoir is similarly provided between the small diameter portion 31 of the drive shaft 11 inserted through the insertion portion 15 and the large diameter portion 29 of the insertion portion 15.

  Here, the outer diameter of the drive shaft 11 can be supported by the inner diameter of the insertion portions 13 and 15 by setting the inner diameter DH1 of the sliding support portions 17 and 19 and the outer diameter DS1 of the drive shaft 11 to be substantially equal. it can. Further, by increasing the inner diameter DH2 of the large diameter portions 27 and 29 relative to the inner diameter DH1 of the sliding support portions 17 and 19, the inner diameters of the insertion portions 13 and 15 are increased to improve the flow of the lubricating oil, and the lubricating oil Can have a centrifugal pump function. Further, by making the outer diameter DS2 of the small diameter portion 31 of the drive shaft 11 smaller than the inner diameter DH1 of the sliding support portions 17 and 19, the inner diameter DH2 of the large diameter portions 27 and 29 and the outer diameter DS2 of the small diameter portion 31 are reduced. An annular space can be formed between them, and a lubricating oil reservoir 33 can be provided.

  A plurality of ribs 37 are provided on the outer periphery of the flange portion 35 of the differential case 3 at equal intervals in the circumferential direction. The rib 37 is inclined so as to gradually increase in thickness in the axial direction from the outer diameter side toward the inner diameter side, and the supply path 21 is positioned at the inner diameter side tip of the rib 37. The rib 37 can improve the strength of the differential case 3 and can introduce the lubricating oil scraped up by the ring gear 4 through the rib 37 into the supply path 21. In addition, a plurality of hole portions 61 that penetrates the inside and the outside of the differential case 3 are provided between the ribs 37 on the inner diameter side. By providing the hole 61 between the ribs 37, the lubricating oil accumulated between the ribs 37 can be easily introduced into the differential case 3, and the gear meshing portion and the sliding portion inside the differential case 3 can be reliably lubricated. it can. In addition, the differential case 3 is provided with a plurality of flow portions 63 through which lubricating oil flows between the inside and the outside of the differential case 3.

  In such a differential device 1, sliding support portions 17 and 19 that slide and support the drive shaft 11 are provided on the inner periphery of the insertion portions 13 and 15 through which the drive shaft 11 of the differential case 3 is inserted. , 15 are provided with supply passages 21, 23 through which the sliding support portions 17, 19 are communicated with the outer peripheral sides of the insertion portions 13, 15 and the lubricating oil pumped up by the ring gear 4 by the rotation of the differential case 3 is supplied. Therefore, the lubricating oil can be directly supplied to the sliding support portions 17 and 19.

  Therefore, the lubricating oil can be reliably supplied to the sliding portion between the drive shaft 11 and the support portion of the differential case 3.

  The supply paths 21 and 23 are provided on the inner side of the differential case 3 in the axial direction of the insertion sections 13 and 15, and are supplied from the supply paths 21 and 23 to a portion where the sliding support parts 17 and 19 on the outer periphery of the drive shaft 11 are located. Since the spiral groove 25 for guiding the lubricated oil to the outside of the differential case 3 in the axial direction is provided, the lubricant flowing in from the supply passages 21 and 23 is reliably supplied to the outside in the axial direction inside the differential case 3. Can do.

  Furthermore, since the insertion portions 13 and 15 are provided with large diameter portions 27 and 29 having an inner diameter larger than that of the sliding support portions 17 and 19 on the inner side of the differential case 3 in the axial direction, they are introduced from the supply paths 21 and 23. The lubricating oil can be easily distributed to the large diameter portions 27 and 29, and the lubricating oil can be provided with a centrifugal pump function so that the lubricating oil can be easily introduced into the differential case 3.

  Further, the drive shaft 11 is provided with a small-diameter portion 31 having an inner diameter smaller than that of the sliding support portions 17 and 19, and a lubricating oil reservoir 33 is provided between the small-diameter portion 31 and the large-diameter portions 27 and 29. Therefore, it is possible to prevent the lubricating oil introduced into the differential case 3 from being exhausted.

  Further, a plurality of ribs 37 inclined so as to gradually increase in thickness from the outer diameter side toward the inner diameter side are provided on the flange portion 35 to which the ring gear 4 of the differential case 3 is fixed, and the supply path 21 has an inner diameter of the rib 37. Therefore, it is possible to easily introduce the lubricating oil scraped up by the ring gear 4 into the supply path 21 via the rib 37.

  In the differential device according to the embodiment of the present invention, the drive shaft is provided with a spiral groove as a guide path. However, a spiral groove may be provided in the sliding support portion of the insertion portion of the differential case. The guide path is not limited to the spiral groove, and may have any configuration as long as it can guide the lubricating oil from the supply path to the sliding support portion.

  Further, although the differential device according to the embodiment of the present invention is a bevel gear type differential device, the parallel shaft type differential device also includes a planetary gear having a configuration of a carrier, an internal gear, a pinion, a sun gear, and the like. The configuration of the present invention can also be applied to a type of differential apparatus.

It is XPZX sectional drawing in FIG. 3 of the differential apparatus which concerns on embodiment of this invention. It is a principal part expanded sectional view of the differential apparatus which concerns on embodiment of this invention. It is a left view of the differential apparatus which concerns on embodiment of this invention. It is a right view of the differential apparatus which concerns on embodiment of this invention. FIG. 4 is a cross-sectional view taken along the line X-X-X in FIG. 3 of the case body of the differential device according to the embodiment of the present invention. 5 is a PY cross-sectional view of the case main body of the differential device according to the embodiment of the present invention in FIG. It is PZ sectional drawing of FIG. 3 of the cover member of the differential apparatus which concerns on embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Differential apparatus 2 ... Carrier 3 ... Differential case 4 ... Ring gear 5, 7 ... A pair of side gear 9 ... Pinion 11 ... Drive shaft 13, 15 ... Insertion part 17, 19 ... Sliding support part 21, 23 ... Supply path 25 ... Spiral Groove (guideway)
27, 29 ... Large diameter part 31 ... Small diameter part 33 ... Lubrication oil reservoir 35 ... Flange part (fixed part)
37 ... Ribs

Claims (5)

A differential case that is rotatably accommodated in a carrier in which lubricating oil is sealed and a ring gear is fixed, a pair of side gears that are rotatably accommodated in the differential case, and a differential rotation of the pair of side gears that meshes with the pair of side gears A differential device provided with a pinion that is rotationally driven integrally with the differential case in the rotational direction of the differential case, and a drive shaft that is inserted through the differential case and connected to the pair of side gears,
The differential case is provided with a hollow insertion portion through which the drive shaft is inserted at both ends in the axial direction, and a sliding support portion that slides and supports the drive shaft is provided on the inner periphery of the insertion portion. The insertion portion is provided with a supply path through which the sliding support portion and the outer peripheral side of the insertion portion communicate with each other and to which the lubricating oil scraped up by the ring gear by rotation of the differential case is supplied. A differential device characterized by that. The differential device according to claim 1,
The supply path is provided on the inner side of the differential case in the axial direction of the insertion portion, and either one of the sliding support portion and the portion where the sliding support portion on the outer periphery of the drive shaft is located, A differential apparatus characterized in that a guide path is provided for guiding the lubricating oil supplied from the supply path to the outside of the differential case in the axial direction. A differential device according to claim 1 or 2,
The differential device according to claim 1, wherein a large-diameter portion having an inner diameter larger than that of the sliding support portion is provided in the insertion portion on the inner side of the differential case in the axial direction. A differential device according to claim 3, wherein
The drive shaft is provided with a small-diameter portion having an inner diameter smaller than that of the sliding support portion, and a lubricating oil reservoir for storing the lubricating oil is provided between the small-diameter portion and the large-diameter portion. A differential device. A differential device according to any one of claims 1 to 4,
The fixed portion of the differential case to which the ring gear is fixed is provided with a plurality of ribs inclined so as to gradually increase in thickness from the outer diameter side toward the inner diameter side, and the supply path is provided on the inner diameter side of the rib A differential apparatus, characterized in that the differential apparatus is located in the vicinity of an end portion of the first embodiment.

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