JP2007139167A - Differential - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent local abutting of a side gear to an input member, and to improve durability of a differential. <P>SOLUTION: The differential 300 includes the rotatable input member, and a differential mechanism 2 rotatable by the input member and permitting the differential between first and second output shafts. The differential mechanism 2 includes first and second differential members respectively connected to the first and the second output shafts and relatively rotatable with each other, and a clutch for fastening one of the first and the second differential members and the input member and restricting the differential between the first and the second output shafts. The clutch includes a clutch member pushed toward the input member by the one differential member, and the clutch member is movable with respect to the one differential member along the radial direction. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a differential having a differential limiting mechanism.

The related differential includes a differential case and a pair of side gears housed in the differential case and capable of differential movement. Each side gear is connected to an axle. The differential includes a cone clutch capable of limiting the differential between the side gears. The cone clutch includes a cone surface of a differential case and a side gear that are slidably fastened to each other.
The cone surface of the differential case centers the side gear. The boss portion of the differential case centers the axle.
Japanese Patent Laid-Open No. 2003-254408

  However, the boss portion and the cone surface are arranged close to each other in the rotation axis direction. Close centered double centering should be avoided as it will cause local contact to the axle boss or local contact to the side gear cone surface.

  An object of the invention is to provide a differential with improved durability.

  The inventive features provide the following differentials. The differential includes a rotatable input member. The differential includes a differential mechanism that is rotatable by the input member and allows a differential between the first and second output shafts. The differential mechanism includes first and second differential members that are connected to the first and second output shafts and are rotatable relative to each other. The differential includes a clutch that restricts a differential between the first and second output shafts by fastening one of the first and second differential members and the input member. The clutch includes a clutch member that is pushed toward the input member by the one differential member. The clutch member is movable in the radial direction with respect to the one differential member.

  A radial gap may be provided between the clutch member and the one differential member.

  The clutch member may be rotatable in synchronization with the one differential member.

  The clutch member may be coupled to the one differential member by an uneven portion provided mutually.

  The clutch may be a cone clutch.

  A connecting portion that is connected to the output shaft may be formed on an inner peripheral side of the one differential member, and the clutch member may be disposed radially outward with respect to the connecting portion.

  The first and second differential members may include a connection gear portion that forms the differential mechanism, and the clutch member may be disposed on the outer side in the rotation axis direction with respect to the connection gear portion.

  The input member and the output shaft may directly support each other, and the differential member and the input member may support each other via the clutch member.

  The clutch member is positioned by the input member, and the one side gear is not positioned with respect to the input member. This structure prevents local contact of the side gear with the input member and improves durability.

  An embodiment of the invention will be described with reference to FIGS. Similar members are denoted by the same reference numerals, and description thereof is omitted.

Referring to FIG. 1, drive train 100 includes an engine 101 as a power source and a transmission 103 connected to engine 101. The drive train 100 includes a center differential 200 as an output unit of the transmission 103 and a transfer 210 connected to the center differential 200.
The transfer 210 includes a front differential 220 that is rotatably connected to the side gear 205 of the center differential 210. The transfer 210 includes a drive gear 213 rotatably connected to the side gear 207 of the center differential 200. The transfer 210 includes a pinion gear 217 that is rotatably connected to the drive gear 213. The transfer 210 includes a hydraulic clutch 230 that can be connected to the drive gear 213 and the front differential 20.

  Side gears 223 and 225 of front differential 220 are connected to both axles 107 and 111 connected to front wheels 109 and 113, respectively.

  Drive train 100 includes a propeller shaft 115 connected to pinion gear 217, and a rear differential 300 connected to propeller shaft 115 via pinion gear 117. The side gears 24 and 23 of the rear differential 300 are connected to axles 119 and 123 (output shafts) connected to the rear wheels 121 and 125.

  The present invention can be applied to any of the center differential 200, the front differential 220, and the rear differential 300, but is mounted on the rear differential 300 as an example.

  Referring to FIG. 2, a differential 300 as a rear differential includes a differential case 1 as an input member, a differential mechanism 2 that can be rotated by the differential case 1, and a differential limiting mechanism 3 that limits the differential of the differential mechanism 2. including.

  The differential case 1 includes a peripheral wall 11 that surrounds the differential mechanism 2, and a flange 12 that extends radially outward from the peripheral wall 11. The differential case 1 includes side walls 13 and 14 extending radially inward from both ends of the peripheral wall 11 and bosses 16 and 17 extending axially outward from the inner periphery of the peripheral walls 13 and 14, respectively. The bosses 16 and 17 and the output shafts 126 and 122 that are part of the axles 123 and 119 and are connected to the wheels 125 and 121 by the constant velocity joints 130 and 128 so as to rotate together are directly supported by the support parts 124 and 120. Is in a supportive relationship.

  The peripheral wall 11 has the 1st attachment hole 11a penetrated to radial direction in the center part. The peripheral wall 11 has a second mounting hole 11b that extends in the axial direction and communicates with the first mounting hole. The peripheral wall 11 has a flow hole 11c that is positioned 90 ° from the first mounting hole 11a. The peripheral wall 11 has conical inner walls 11d and 11e at both ends in the axial direction. The inner walls 11d and 11e approach the rotational axis of the differential case 1 as they extend outward in the axial direction.

  The flange 12 has a mounting hole 12a into which a bolt for fixing the ring gear 26 (see FIG. 1) is inserted.

  The side walls 13 and 14 have flow holes 13a and 14a penetrating in the axial direction. The side walls 13 and 14 have a plurality of detents 13b and 14b protruding in the axial direction from the inner wall. These detents 13b and 14b are positioned at equal intervals in the circumferential direction.

  The cylindrical boss portions 16 and 17 are rotatably supported by the differential carrier 41 (see FIG. 1). The axles 123 and 119 are inserted into the bosses 16 and 17, respectively.

  The differential mechanism 2 includes a pinion shaft 21 fixed to the differential case 1 using a spring pin 18. The spring pin 18 is inserted into the second mounting hole 11 b and passes through the pinion shaft 21. The pinion shaft 21 is a reference in the axial direction of the differential 300. The differential mechanism 2 includes a pinion gear 22 that can rotate around the pinion shaft 21. A spherical washer 27 is disposed between the pinion gear 22 and the inner surface of the peripheral wall 11. The spherical washer 27 supports the back surface of the pinion gear 22 and receives its centrifugal force and meshing reaction force.

  The differential mechanism 2 includes first and second side gears 23 and 24 (hereinafter referred to as side gears) that mesh with the pinion gear 22. The side gears 23 and 24 are not positioned by the differential case 1, but are centered with respect to the axles 123 and 119. The side gears 23 and 24 are in a supporting relationship with the differential case 1 with clutch members 31 and 32 described later interposed therebetween.

  The side gears 23 and 24 include connecting gear portions 23b and 24b having teeth 23a and 24a on the inner side in the axial direction. The connecting gear portions 23b and 24b include annular pressing portions 23j and 24j protruding to the opposite side to the teeth 23a and 24a in the axial direction.

  The side gears 23 and 24 include cylindrical shaft portions 23 c and 24 c that are supported by the inner peripheral surfaces of the side walls 13 and 14.

  The side gears 23 and 24 include connecting portions 23d and 24d between the shaft portions 23c and 24c and the connecting gear portions 23b and 24b. The connecting portions 23d and 24d include four spline grooves 23f and 24f as uneven portions extending in the axial direction on the outer peripheral wall 23e (see FIG. 3). The spline grooves 23f and 24f are positioned at equal intervals in the circumferential direction. The spline grooves 23f and 24f have a semicircular arc bottom 23f1.

  The side gears 23 and 24 have splines 23g and 24g as connecting portions extending in the axial direction on the inner peripheral side thereof. The splines 23g and 24g are connected to the axles 123 and 119.

  The differential limiting mechanism 3 includes a cone clutch 30 between the side gears 23 and 24 and the differential case 1. The cone clutch 30 includes an annular first and second clutch members 31 and 32 (hereinafter referred to as clutch members) and first and second taper rings 33 and 34 (hereinafter referred to as taper rings) that slide relative to each other. including. However, the first and second clutch members 31 and 32 may be directly slid with the differential case 1 except for the tapering.

  The taper rings 33 and 34 include conical friction plates 33a and 34a extending obliquely with respect to the axial direction. The friction plates 33a and 34a are in contact with the inner walls 11d and 11e of the peripheral wall. The taper rings 33 and 34 include engagement plates 33b and 34b extending radially inward from the friction plates 33a and 34a. The engagement plates 33b and 34b are arranged at equal intervals in the circumferential direction. The engagement plates 33b and 34b engage with the rotation stoppers 13b and 14b to prevent the taper rings 33 and 34 from rotating.

  The taperings 33 and 34 are quenched after carburizing. The surfaces of the friction plates 33a and 34a have a number of grooves. This groove disperses the lubricating oil evenly and enhances oil retention. This prevents wear and heat generation and improves durability and stabilizes differential limiting.

  The clutch members 31 and 32 are positioned on the radially outer side of the splines 23g and 24g. The clutch members 31 and 32 are positioned on the outer side in the rotation axis direction of the coupling gear portions 23 b and 24 b of the side gears 23 and 24.

  The clutch members 31 and 32 have conical outer peripheral walls 31a and 32a extending obliquely with respect to the axial direction. The outer peripheral walls 31a and 32a slide with the friction plates 33a and 34a to act as a friction clutch. Referring to FIG. 3, clutch members 31 and 32 have cylindrical inner peripheral walls 31b and 32b. Between the inner peripheral walls 31b and 32b and the outer peripheral walls 23e and 24e, gaps are set that allow relative movement in the radial direction. As an example, a gap S1 is set. The gap S1 allows the clutch members 31 and 32 to move in the radial direction with respect to the side gears 23 and 24, and allows the clutch members 31 and 32 to be positioned with respect to the differential case 1.

  The clutch members 31 and 32 have convex portions 31c and 32c extending in the axial direction on the inner peripheral walls 31b and 32b. The convex portions 31c and 32c have a semicircular tip 31c1. The convex portions 31c and 32c are positioned in the spline grooves 23f and 24f so that the clutch members 31 and 32 and the side gears 23 and 24 can rotate in synchronization. A gap S1 is set between the convex portions 31c and 32c and the spline grooves 23f and 24f. The clutch members 31 and 32 are movable in the axial direction with respect to the side gears 23 and 24.

  Next, the operation of the differential 300 will be described.

  The engine 101 generates torque. This torque is transmitted to the pinion gear 117 through the transmission 103, the center differential 200, the transfer 210, and the propeller shaft 115.

  The pinion gear 117 rotates the differential case 1 while meshing with the ring gear 26. The differential case 1 rotates in synchronization with the pinion shaft 21, the pinion gear 22, the side gears 23 and 24, and the axles 123 and 119.

  When the ground resistance between the left and right wheels 125 and 121 and the road surface is different on the left and right, the side gears 23 and 24 rotate relative to each other to rotate the pinion gear 22 around the pinion shaft 21. This action causes a differential in the axles 123, 199. During this time, the clutch members 31 and 32 rotate in synchronization with the side gears 23 and 24 and rotate relative to the taperings 33 and 34.

  The side gears 23 and 24 that mesh with the pinion gear 22 of the differential mechanism according to the input torque to the differential case 1 cause the side gears 23 and 24 together with the clutch members 31 and 32 to move outward in the axial direction with respect to the pinion shaft 21 by the meshing reaction force. Move. The pressing portions 23j and 24j of the first and second side gears 23 and 24 press the clutch members 31 and 32 against the taper rings 33 and 34, respectively. The outer peripheral walls 31 a and 32 a of the clutch members 31 and 32 and the friction plates 33 a and 34 a of the taper rings 33 and 34 slide with each other to fasten the cone clutch 30. The engagement of the cone clutch 30 limits the relative rotation between the side gears 23 and 24, that is, the differential between the axles 123 and 119.

  According to this embodiment, the clutch members 31 and 32 are positioned by the differential case 1, and the side gears 23 and 24 are not positioned by the differential case 1. The gap S1 described above absorbs minute vibrations and axial misalignment between the clutch member 31 and the side gear 23, and absorbs minute vibrations and axial misalignment between the clutch member 32 and the side gear 24, Stabilizes frictional vibration. That is, this structure prevents local contact and abnormal noise of the side gears 23 and 24 with respect to the differential case 1 and improves durability.

  Further, the clutch members 31 and 32 do not require a hook having a cone surface formed on the outer periphery of the side gears 23 and 24. This structure realizes a one-piece differential case 1 and achieves low cost.

  As described above, the differential of the present invention is a left and right independent suspension system in which constant velocity joints 128 and 130 are provided between the left and right wheel differentials such as the rear differential 300 (or the front differential 220) and the left and right wheels. This is particularly effective for improving the durability of the differential having the drive line.

  The differential 300 may include coupling mechanisms 23h and 31d that couple the side gear 23 and the clutch member 31A as shown in FIG. The coupling mechanism includes four spline grooves 23 h extending radially inward from the outer peripheral wall 23 e of the side gear 23. The spline groove 23h has a rectangular bottom 23h1. The coupling mechanism includes four convex portions 31d positioned in the spline groove 23h. The convex portion 31d extends radially inward from the inner peripheral wall 31b from the clutch member 31A and has a rectangular tip 31d1. A gap S1 is set between the tip 31d1 and the bottom 23h1.

  The differential mechanism according to the embodiment is not limited to a structure using a bevel gear, and can be applied to other differential mechanisms such as a planetary gear or a structure using a plurality of frames. The differential 300 according to the embodiment may be used for a center differential and a front differential.

It is a skeleton figure which shows the power transmission path | route of the vehicle containing the differential which concerns on embodiment of invention. FIG. 1 shows a radial cross-sectional view of the differential shown in FIG. 1, and the upper half and the lower half are sections that are displaced by 90 ° from each other. FIG. 3 is a cross-sectional view of a clutch member and a side gear along III-III in FIG. 2. It is sectional drawing of the clutch member and side gear which concern on a deformation | transformation form.

Explanation of symbols

1 differential case 2 differential mechanism 3 differential limiting mechanism 11 peripheral wall 12 flange 13, 14 side wall 13b, 14b non-rotating 16, 17 boss 22 pinion gear 23 first side gear 24 second side gear 23a, 24a teeth 23b, 24b connecting gear Part 23c, 24c shaft part
23d, 24d connecting portion 23e, 24e outer peripheral wall 23f, 24f spline groove 23g, 24g spline 23h spline groove 31 first clutch member 32 second clutch member 31a, 32a outer peripheral wall 31b, 32b inner peripheral wall 31c, 32c engaging projection 33 First taper ring
34 Second taper ring 33a, 34a Friction plate 33b, 34b Engagement plate 300 Differential

Claims (8)

A rotatable input member;
A differential mechanism that is rotatable by the input member and allows a differential between the first and second output shafts, the differential mechanism being connected to the first and second output shafts, respectively; Including first and second differential members rotatable relative to each other;
A clutch that restricts a differential between the first and second output shafts by fastening one of the first and second differential members and the input member; A clutch member that is pushed toward the input member by the one differential member;
The differential, wherein the clutch member is movable in a radial direction with respect to the one differential member.   The differential according to claim 1, wherein a radial gap is provided between the clutch member and the one differential member.   The differential according to claim 1, wherein the clutch member is rotatable in synchronization with the one differential member.   The differential according to claim 3, wherein the clutch member is coupled to the one differential member by an uneven portion provided to each other.   The differential according to claim 1, wherein the clutch is a cone clutch. A connecting portion connected to the output shaft is formed on the inner peripheral side of the one differential member,
The differential according to claim 1, wherein the clutch member is disposed radially outward with respect to the coupling portion. The first and second differential members include a connecting gear portion that forms the differential mechanism,
The differential according to claim 6, wherein the clutch member is disposed on the outer side in the rotation axis direction with respect to the connection gear portion. The input member and the output shaft are directly supporting each other,
The differential according to claim 1, wherein the differential member and the input member are in a relationship of supporting each other with the clutch member interposed therebetween.

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