Differential device

Abstract

The invention provides a differential device which can maintain turning performance and improve trafficability. A differential device (1) is provided with: a differential case (7) rotatably disposed; a pinion (11) that is rotatably supported within the differential case and revolves by the rotation of the differential case; and a pair of side gears (13, 15) that mesh with the pinion gear and are rotatable relative to each other, in which the pinion gear and the side gears are configured from a bevel gear set, and a first planar portion (39) that is orthogonal to the rotation axis is provided on the rear surface side of the gear portion of the side gears. The differential case is provided with a second planar portion (41) which is orthogonal to the rotating shaft and is disposed so as to face the first planar portion (39) so as to be able to abut against the first planar portion (39), and a first abutting force is applied between the first planar portion (39) and the second planar portion (41) by a biasing member (43). The meshing reaction force between the pinion gear and the side gear imparts a second abutting force between the first planar portion (39) and the second planar portion (41).

Description

TECHNICAL FIELD

[0001] The present application relates to a differential device. BACKGROUND

[0002] In the past, as a differential device, there has been one that is provided with a differential case configured to be rotatable, and a pinion gear supported in the differential case so as to be able to self-rotate and revolve by rotation of the differential case. Further, there is known a structure provided with a pair of side gears that are able to relatively rotate and mesh with the pinion gear (see Patent Literature 1). In this differential device, the pinion gear and the side gears are constituted by bevel gear sets. A pressing member constituted by a conical spring washer is disposed between the differential case and the side gears in the axial direction.

[0003] The pressing member presses the side gears toward the pinion gear side, and makes the backlash of the side gears and the pinion gear to be 0. Therefore, each time the teeth that mesh with the pinion gear are exchanged one by one, the side gears reciprocate in the rotational axis direction, and are slightly vibrated in the rotational axis direction. The slight vibration of the side gears is transmitted to the tire, and is imparted to the tire in the width direction. The tire to which the slight vibration is imparted increases the coefficient of friction with respect to the rotation direction of the road surface, and suppresses the slip of the tire.

[0004] PRIOR ART DOCUMENTS

[0005] PATENT LITERATURE

[0006] Patent Literature 1: Japanese Patent Application Laid-Open No. 2011-247300 SUMMARY

[0007] PROBLEMS TO BE SOLVED BY THE INVENTION

[0008] However, in the differential device of Patent Literature 1 described above, if the pressing force of the pressing member, that is, the initial torque is increased, the region of the differential restriction characteristic can be expanded, but the running resistance of the left and right wheels increases, the vehicle is difficult to turn, and the cornering performance is reduced.

[0009] The present application has been achieved in view of the problems of the related art. Further, an object of the present application is to provide a differential device that is capable of improving the passability while maintaining the cornering performance.

[0010] MEANS FOR SOLVING THE PROBLEMS

[0011] The differential device according to the present embodiment includes a differential case configured to be rotatable, a pinion supported in the differential case so as to be able to rotate about its own axis and revolve by rotation of the differential case, and a pair of side gears engaged with the pinion and able to rotate relative to each other, the pinion and the side gears being configured by a bevel gear set, a first flat surface portion orthogonal to the rotation axis is provided on the back surface side of the gear portion of the side gear, a second flat surface portion orthogonal to the rotation axis is provided in the differential case and is disposed so as to be able to abut against the first flat surface portion, a first abutting force is applied between the first flat surface portion and the second flat surface portion by a force applying member, and a second abutting force is applied between the first flat surface portion and the second flat surface portion by the meshing reaction force of the pinion and the side gears.

[0012] Effects of Invention

[0013] According to the present application, a differential device that is able to improve passability while maintaining cornering performance can be provided. BRIEF DESCRIPTION OF DRAWINGS

[0014] Figure 1 is a cross-sectional view of the differential device of the first embodiment.

[0015] Figure 2 is a perspective view of the force applying member and the plate of the differential device of the first embodiment.

[0016] Figure 3 is a characteristic line graph of the torque characteristics of the differential device of the present embodiment, the torque characteristics of a comparative example, and the initial torque.

[0017] Figure 4 is a cross-sectional view of the differential device of the second embodiment.

[0018] Figure 5 is a cross-sectional view of the differential device of the third embodiment. DETAILED DESCRIPTION

[0019] Hereinafter, the differential device of the present embodiment will be described in detail using the drawings. Furthermore, the dimensional ratios of the drawings are exaggerated for ease of explanation and can differ from actual ratios.

[0020] (First Embodiment)

[0021] Use Figures 1-3 The first embodiment will be described.

[0022] As Figure 1As shown, the differential device 1 of this embodiment is disposed, for example, between a drive source (not shown) such as an engine or electric motor and the left and right wheels (not shown). The driving force from the drive source is transmitted to the differential device 1 via a transmission (not shown), and the driving force is distributed to the left and right wheels (not shown) via a pair of output axes.

[0023] like Figure 1 , Figure 2 As shown, the differential device 1 includes a differential mechanism 3 and a differential limiting part 5.

[0024] The differential mechanism 3 includes a differential housing 7, a pinion shaft 9, a pinion 11, and a pair of side gears 13 and 15.

[0025] The differential housing 7 has bosses 17 and 19 formed on both axial sides, each rotatably supported on a stationary component such as a planetary carrier via bearings 21 and 23 on its outer periphery. A flange 27 is formed in the differential housing 7, on which a gear ring 25 is fixed. The gear ring 25 meshes with a power transmission gear (not shown) that transmits driving force, causing the differential housing 7 to rotate. The differential housing 7 houses a pinion shaft 9, a pinion 11, and a pair of side gears 13 and 15.

[0026] The pinion shaft 9 engages with a hole formed in the differential housing 7 at its end, and is prevented from disengaging and rotating by a pin, and is driven to rotate integrally with the differential housing 7. The pinion shaft 9 is housed in a block component 29 that positions a pair of side gears 13 and 15 in the axial direction with both ends exposed to the outside. A pinion 11 is supported on each of the two ends of the pinion shaft 9.

[0027] Multiple pinions 11 are arranged at equal intervals (in this case, two) around the circumference of the differential housing 7. Each pinion 11 is supported on the end side of the pinion shaft 9 and revolves around the differential housing 7. Each pinion 11 is rotatably supported on the pinion shaft 9 in a manner that allows it to be rotated when the meshing pair of side gears 13 and 15 rotate differentially. The pinions 11 transmit the driving force input to the differential housing 7 to the pair of side gears 13 and 15.

[0028] A pair of side gears 13 and 15 are housed within the differential housing 7 in a manner that allows them to rotate relative to each other. The pair of side gears 13 and 15 mesh with a pinion 11. The pinion 11 and the pair of side gears 13 and 15 are composed of a bevel gear set. Spline-shaped output sections 31 and 33 are provided on the inner circumference of the pair of side gears 13 and 15, outputting the driving force transmitted to them. A pair of output shafts 35 and 37 are integrally rotatably connected to the output sections 31 and 33, and these output shafts 35 and 37 are integrally rotatably connected to the left and right wheels.

[0029] The differential restriction portion 5 is provided between the differential case 7 and each of the pair of side gears 13, 15. The differential restriction portion 5 has a first flat portion 39 and a second flat portion 41 which slide against each other, and a force applying member 43.

[0030] The first flat portion 39 is provided on the back side of the gear portion of the side gears 13, 15. The first flat portion 39 extends in a direction orthogonal to the rotation axis of the side gears 13, 15. The first flat portion 39 is arranged so as to be able to abut against the second flat portion 41 in the direction of the rotation axis. The inner end portion of the first flat portion 39 on the inner diameter side is a recessed portion 40 which is recessed toward the pinion gear 11 side in a manner to be away from the second flat portion 41 in the axial direction. Therefore, the inner end portion of the first flat portion 39 on the inner diameter side does not slide against the second flat portion 41, and does not affect the differential restriction characteristics of the differential restriction portion 5.

[0031] The second flat portion 41 is provided on a plate 45 which is arranged so as to be able to rotate integrally with the differential case 7. In addition, the second flat portion 41 is a structure which is formed or arranged so as to rotate in conjunction with the differential case 7 directly or indirectly, and is a structure which abuts against the first flat portion 39 in a manner to generate relative rotation. By providing the second flat portion 41 on the plate 45, the design of the second flat portion 41 can be performed independently of the design of the differential case 7. The plate 45 is formed in a ring shape in a manner to have an opening 47 which penetrates in the direction of the rotation axis. By providing the opening 47 in the plate 45, it is possible to easily supply lubricating oil to the second flat portion 41, and it is possible to improve the lubricating property. The second flat portion 41 is a ring-shaped portion of the plate 45, and is arranged so as to be able to abut against the first flat portion 39 in the direction of the rotation axis. The second flat portion 41 extends in a direction orthogonal to the rotation axis of the differential case 7 in a manner to be parallel to the first flat portion 39.

[0032] A plurality of (six in this case) engagement protrusions 49 are provided on the plate 45 at equal intervals in the circumferential direction of the second flat portion 41, and protrude toward the inner diameter side from the second flat portion 41. The engagement protrusions 49 engage with a plurality of (six in this case) engagement recesses 50 formed in the differential case 7. The engagement protrusions 49 and the engagement recesses 50 constitute a linking portion 51 which enables the plate 45 to rotate integrally with the differential case 7. The linking portion 51 is arranged on the inner diameter side of the first flat portion 39 and the second flat portion 41. Therefore, the linking portion 51 does not protrude to the outer side in the radial direction, and it is possible to downsize the differential case 7 in the radial direction. The pinion gear 11 and the pair of side gears 13, 15, the block member 29, and the plate 45 are fitted into the differential case 7 from the peripheral wall (not shown) of the differential case 7.

[0033] The urging member 43 is formed of one member continuous with the plate 45. The urging member 43 is provided with a plurality of (six in this case) elastic portions in the plate 45 at portions linking the second flat portion 41 and the engagement protrusion 49. Pressing forces of these elastic portions act as a whole to exert the urging force of the urging member 43. The urging member 43 is inclined so that the pressing portion 53 linked to the second flat portion 41 side is located on the pinion 11 side than the engagement protrusion 49 with respect to the rotational axis direction. The pressing portion 53 of the urging member 43 is disposed at a position on the outer diameter side than the linking portion 51 in a state where the plate 45 is disposed to the differential case 7. The urging member 43 abuts against the annular fulcrum member 57 housed in the housing groove 55 continuously formed in the circumferential direction on the outer diameter side of the linking portion 51 of the differential case 7 in a state where the plate 45 is disposed to the differential case 7. In addition, the fulcrum member 57 is stopped at a plurality of portions in the circumferential direction in the housing groove 55. However, the annular fulcrum member 57 is not essential, and the axial end portion of the plate 45 on the inner diameter side can abut against the axial end portion of the engagement recess 50 formed in the differential case 7 to receive the reaction force of the urging force.

[0034] The urging member 43 imparts the first abutting force of the second flat portion 41 pressing the first flat portion 39 with the abutting portion of the fulcrum member 57 as a fulcrum. The first abutting force of the urging member 43 brings the first flat portion 39 and the second flat portion 41 into abutment, generates a frictional resistance to the differential restriction portion 5, and imparts the initial torque. By imparting the initial torque to the differential restriction portion 5, it is possible to stabilize the differential restriction characteristic. The first abutting force of the urging member 43 is input to the block member 29 disposed between the pair of side gears 13, 15. By receiving the first abutting force of the urging member 43 by the block member 29, it is possible to secure the backlash in the gear portions of the pinion 11 and the side gears 13, 15.

[0035] The first flat portion 39 and the second flat portion 41 in the differential restriction portion 5 are imparted with the second abutting force from the pair of side gears 13, 15 moved in the axial direction by the meshing reaction force with the pinion 11 according to the magnitude of the driving force (driving torque) input to the differential case 7. The differential restriction portion 5 brings the first flat portion 39 and the second flat portion 41 to slide by imparting the second abutting force to the first flat portion 39 and the second flat portion 41, thereby restricting the differential of the differential mechanism 3. Such a differential restriction portion 5 becomes a torque-sensing type friction clutch.

[0036] In the differential device of the related art, the side gears 13, 15 are forced by the force applying member to the side of the pinion 11, and the backlash in the gear portions of the pinion 11 and the side gears 13, 15 is made to be zero. Therefore, each time the teeth engaging with the pinion 11 are exchanged one by one, the side gears 13, 15 reciprocate in the rotation axis direction, and a slight vibration in the rotation axis direction is generated. The slight vibration of the side gears 13, 15 is transmitted to the wheels, and a slight vibration is imparted to the wheels in the width direction of the wheels. The wheels to which the slight vibration is imparted increase the friction coefficient with respect to the rotation direction of the road surface, and the wheels are suppressed from idling. In such a differential device, if the force of the force applying member, that is, the initial torque is increased, the region of the differential restriction characteristic can be expanded. However, if the initial torque is excessively increased, the differential rotation of the left and right wheels is easily absorbed, the travel resistance is increased, the vehicle is difficult to turn, and the cornering performance is reduced.

[0037] In contrast, in the differential device 1, the first flat portion 39 and the second flat portion 41 are provided between the differential case 7 and the side gears 13, 15. Between the first flat portion 39 and the second flat portion 41, the first abutting force as the initial torque is imparted by the force applying member 43. The engagement reaction force of the pinion 11 and the side gears 13, 15 imparts the second abutting force between the first flat portion 39 and the second flat portion 41. The first flat portion 39 and the second flat portion 41 to which the second abutting force is imparted can obtain the differential restriction characteristic of restricting the differential of the differential restriction mechanism 3 (the pair of side gears 13, 15) by the sliding of each other. Therefore, as long as the first abutting force of the force applying member 43 is adjusted in accordance with the desired differential restriction characteristic, the initial torque does not become excessively high. Therefore, the differential restriction characteristic does not become excessively high, the cornering performance of the vehicle can be maintained, the wheels are suppressed from idling, and the passability of the vehicle is improved.

[0038] In the differential restriction portion 5, the first abutting force generated by the force applying member 43 is input from the second flat portion 41 to the first flat portion 39, and the second abutting force generated by the engagement reaction force is input from the first flat portion 39 to the second flat portion 41. Therefore, in the rotation axis direction, the directions of the initial torque and the differential restriction characteristic of the torque induction type become opposite directions, and thus stable performance in which each characteristic is exerted can be obtained.

[0039] The surface of at least one of the first flat portion 39 and the second flat portion 41 (here, the second flat portion 41) is provided with a friction member 59. By providing the friction member 59 between the first flat portion 39 and the second flat portion 41, the friction characteristics of the first flat portion 39 and the second flat portion 41 are stabilized and the wear is suppressed, and thus the differential restriction characteristic is stabilized. In addition, the friction member 59 can be integrally fixed to the first flat portion 39 side.

[0040] An oil groove is provided on the surface of at least one of the first flat portion 39 and the second flat portion 41.Figure 1 In the example of FIG. 8, the oil groove 48 is provided to the second flat portion 41. The lubricating oil flowing into the inside of the differential case 7 flows in the oil groove. By providing the oil groove between the first flat portion 39 and the second flat portion 41, the frictional characteristics of the first flat portion 39 and the second flat portion 41 are stabilized and the wear is suppressed, and the differential limiting characteristics are stabilized. In addition, the oil groove can be provided to the surface of the friction member 59 which is directly or indirectly fixed to the second flat portion 41 or the first flat portion 39.

[0041] Here, the differential limiting characteristics of the differential limiting portion 5 are evaluated by the torque ratio (torque bias ratio: TBR) of the pair of side gears 13, 15. The TBR is indicated by the ratio of the torque of the low-rotation side to the torque of the high-rotation side. The lockup rate of the differential limiting portion 5 required to become the target TBR is obtained by the formula (TBR-1) / (TBR+1). The clutch torque in the differential limiting portion 5 when the input torque is T and the lockup rate of the differential limiting portion 5 is C can be found by the formula TxC.

[0042] For example, in the differential limiting portion 5, the two sliding surfaces which slide against each other are provided as conical sliding surfaces which are obliquely arranged so as to cross the rotation axis. In the conical sliding surfaces, the second abutting force generated by the meshing reaction force of the pinion 11 and the side gears 13, 15 of the bevel gear set is excessively received, and the TBR (differential limiting characteristics) becomes excessively high. If the TBR becomes excessively high, the first abutting force of the biasing member 43 as the initial torque must also be made high.

[0043] In contrast to this, in the differential limiting portion 5, the first flat portion 39 and the second flat portion 41 which slide against each other are orthogonal sliding surfaces with respect to the rotation axis, and the TBR (differential limiting characteristics) does not become excessively high. Therefore, the differential limiting characteristics of the differential limiting portion 5 are not excessively increased, and the first abutting force of the biasing member 43 does not need to be excessively increased.

[0044] Here, Figure 3 A characteristic line diagram showing the torque characteristics 61 of the differential limiting portion 5 of the present embodiment and the torque characteristics 63 of the differential limiting portion of the comparative example is shown in FIG. 10. In addition, in the differential limiting portion 5 of the present embodiment, the TBR obtained by the sliding friction of the first flat portion 39 and the second flat portion 41 which are respectively set by the present embodiment of the application and slide against each other is set to 1.5, and in the differential limiting portion of the comparative example, the TBR obtained by the sliding friction in the inside of the differential device using a general bevel gear is set to 1.3. In addition, the initial torque 65 in the differential limiting portion 5 of the present embodiment, the initial torque 67 in the differential limiting portion of the comparative example, and the initial torque 69 when the initial torque is expanded are shown in FIG. 11. In addition, the initial torque of the differential limiting portion 5 of the present embodiment and the differential limiting portion of the comparative example is set to the same value. Figure 3 In addition, in the differential limiting portion 5 of the present embodiment, the TBR obtained by the sliding friction of the first flat portion 39 and the second flat portion 41 which are respectively set by the present embodiment of the application and slide against each other is set to 1.5, and in the differential limiting portion of the comparative example, the TBR obtained by the sliding friction in the inside of the differential device using a general bevel gear is set to 1.3. In addition, the initial torque 65 in the differential limiting portion 5 of the present embodiment, the initial torque 67 in the differential limiting portion of the comparative example, and the initial torque 69 when the initial torque is expanded are shown in FIG. 11. In addition, the initial torque of the differential limiting portion 5 of the present embodiment and the differential limiting portion of the comparative example is set to the same value.

[0045] From Figure 3 It is understood that, compared with expanding the initial torque to expand the effective range, setting the initial torque to the same value and setting the TBR to 1.5 can obtain greater effect. In addition, there is no such side effect that the vehicle is difficult to turn. In contrast, if only the initial torque is increased as the initial torque 69, the side effect of the turning performance deterioration that the vehicle is difficult to turn on the low torque side is likely to occur.

[0046] In such a differential device 1, there are provided a differential case 7 configured to be rotatable, and a pinion 11 supported in the differential case 7 so as to be able to rotate around the differential case 7 and revolve around the differential case 7 by rotation of the differential case 7. In addition, there are provided a pair of side gears 13, 15 which are engaged with the pinion 11 and are able to rotate relative to each other. In addition, the pinion 11 and the side gears 13, 15 are configured by a bevel gear set. In addition, a first flat surface portion 39 orthogonal to the rotation axis is provided on the back side of the gear portion of the side gears 13, 15. In addition, a second flat surface portion 41 orthogonal to the rotation axis and configured to be able to abut against the first flat surface portion 39 is provided on the differential case 7. In addition, between the first flat surface portion 39 and the second flat surface portion 41, a first abutting force is imparted by a force applying member 43. Furthermore, a second abutting force is imparted between the first flat surface portion 39 and the second flat surface portion 41 by the meshing reaction force of the pinion 11 and the side gears 13, 15.

[0047] The first flat surface portion 39 and the second flat surface portion 41 to which the second abutting force is imparted are able to obtain a differential limiting characteristic that limits the differential of the pair of side gears 13, 15 by sliding against each other. Therefore, as long as the first abutting force of the force applying member 43 is adjusted in accordance with the desired differential limiting characteristic, the initial torque does not become excessively high. Therefore, the differential limiting characteristic does not become excessively high, the turning performance of the vehicle can be maintained, and the wheel spin is suppressed, and the passability of the vehicle is improved. In addition, the first flat surface portion 39 and the second flat surface portion 41 become sliding surfaces orthogonal to the rotation axis, so the differential limiting characteristic does not become excessively high. Therefore, the differential limiting characteristic does not need to be excessively high, and the first abutting force of the force applying member 43 does not need to be excessively high.

[0048] Therefore, in such a differential device 1, it is possible to improve the passability while maintaining the turning performance.

[0049] In addition, the second flat surface portion 41 is provided on a single plate 45 configured to be able to rotate integrally with the differential case 7. Furthermore, a linking portion 51 linking the differential case 7 and the plate 45 so as to be able to rotate integrally is provided on the inner diameter side of the first flat surface portion 39 and the second flat surface portion 41.

[0050] By providing the second flat portion 41 on the plate 45, the design of the second flat portion 41 can be carried out independently of the design of the differential housing 7. Furthermore, the connecting portion 51 is disposed on the inner diameter side of the first flat portion 39 and the second flat portion 41. Therefore, the connecting portion 51 does not extend radially outward, enabling the differential housing 7 to be miniaturized radially.

[0051] In addition, the force-applying component 43 is formed from a component that is continuous with the plate 45, and the pressing part 53 that imparts the first abutment force is positioned on the outer diameter side of the connecting part 51.

[0052] Therefore, by means of the force-applying member 43, which is formed by a single component continuous with the plate 45, a first contact force can be applied between the first planar portion 39 and the second planar portion 41. In addition, the number of components can be reduced.

[0053] In addition, the inner end portion of the first planar portion 39 is configured to be separated from the second planar portion 41 in the direction of rotation axis, on the inner diameter side.

[0054] Therefore, the inner end of the first planar portion 39 will not slide against the second planar portion 41 on the inner diameter side, and will not affect the differential limiting characteristics.

[0055] In addition, the plate 45 is provided with an opening 47 that extends through the rotation axis.

[0056] Therefore, lubricating oil can be easily supplied to the second flat portion 41, thereby improving lubricity.

[0057] Additionally, a block member 29 is disposed between a pair of side gears 13 and 15. Moreover, the first abutting force of the force-applying member 43 is applied to the pair of side gears 13 and 15 via the block member 29.

[0058] By bearing the first abutting force of the force-applying member 43 on the block member 29, the backlash in the gear portions of the pinion 11 and the side gears 13 and 15 can be ensured. Furthermore, the first abutting force generated by the force-applying member 43 is input from the second plane portion 41 to the first plane portion 39, and the second abutting force generated by the meshing reaction force is input from the first plane portion 39 to the second plane portion 41. Therefore, in the direction of rotation, the directions of initial torque generation and differential limiting characteristics become opposite, thus enabling stable performance that fully utilizes their respective characteristics.

[0059] In addition, a friction element 59 is provided on the surface of at least one of the first flat portion 39 and the second flat portion 41.

[0060] Therefore, the frictional characteristics between the first planar portion 39 and the second planar portion 41 can be stabilized, wear can be suppressed, and the differential limiting characteristics can be stabilized.

[0061] In addition, an oil groove is provided on the surface of at least one of the first flat portion 39 and the second flat portion 41.

[0062] Therefore, the frictional characteristics between the first planar portion 39 and the second planar portion 41 can be stabilized, wear can be suppressed, and the differential limiting characteristics can be stabilized.

[0063] (Second Implementation)

[0064] use Figure 4 The second embodiment will be described.

[0065] In the differential device 101 of this embodiment, the force-applying member 103 is disposed between at least one of a pair of side gears 13, 15 and the block member 29.

[0066] Furthermore, the same reference numerals are used to mark the same structures as in the first embodiment, and the functional descriptions are omitted with reference to the first embodiment. However, since the structures are the same, the functions / effects are the same.

[0067] like Figure 4 As shown, the force-applying component 103 is composed of a disc spring. The force-applying component 103 is respectively disposed between a pair of side gears 13, 15 and the block component 29 in the direction of rotation. The force-applying component 103 is radially supported on the block component 29. The force-applying component 103 applies force to the side gears 13, 15 toward the inner surface of the differential housing 7, imparting a first abutting force as an initial torque between the first planar portion 39 and the second planar portion 41. The first abutting force of the force-applying component 103 is input from the first planar portion 39 to the second planar portion 41. On the other hand, a second abutting force generated by the meshing reaction force is input from the first planar portion 39 to the second planar portion 41. Therefore, in the direction of rotation, the direction generating the initial torque and the differential limiting characteristic becomes the same direction, thus enabling a larger TBR (differential limiting characteristic) to be generated with a smaller force from the force-applying component 103.

[0068] In this differential assembly 101, a force-applying member 103 is disposed between at least one of a pair of side gears 13, 15 and a block member 29. Each plate 45, forming a second flat portion 41 opposite to the first flat portion 39 of the pair of side gears 13, 15, is separately disposed from the force-applying member 103 as described above. Therefore, the plate 45 can be formed from a planar flat plate, which can suppress the structural complexity of the inner surface side of the differential housing 7.

[0069] The first abutting force generated by the force-applying component 103 is input from the first flat portion 39 to the second flat portion 41, and the second abutting force generated by the meshing reaction force is input from the first flat portion 39 to the second flat portion 41. Therefore, in the direction of rotation axis, the direction in which the initial torque and differential limiting characteristics are generated are the same, so a large differential limiting characteristic can be generated with a small force from the force-applying component 103.

[0070] (Third Implementation)

[0071] use Figure 5 The third embodiment will be described.

[0072] In the differential device 201 of this embodiment, the force-applying member 203 is disposed between the differential housing 7 and the plate 45 and is supported radially by the differential housing 7.

[0073] Furthermore, the same reference numerals are used to mark structures that are the same as those in other embodiments, and functional descriptions are omitted with reference to other embodiments, but since they are the same structures, the resulting functions / effects are the same.

[0074] like Figure 5 As shown, the force-applying component 203 is composed of a disc spring. The force-applying component 203 is respectively disposed between a planar plate 45 located on the back side of the gear portion of a pair of side gears 13, 15 and the rotation axis direction of the differential housing 7. The force-applying component 203 is radially supported by a portion whose inner diameter side is located on the outer diameter side of the connecting portion 51 of the differential housing 7. Alternatively, the force-applying component 203 can be radially supported on the plate 45, or its outer diameter side can be supported on the differential housing 7. The force-applying component 203 applies force to the plate 45 towards the side gears 13, 15, applying a first abutting force as an initial torque between the first planar portion 39 and the second planar portion 41. The first abutting force generated by the force-applying component 203 is input from the second planar portion 41 to the first planar portion 39. On the other hand, a second abutting force generated by the meshing reaction force is input from the first planar portion 39 to the second planar portion 41. Therefore, in the direction of rotation, the directions of generating initial torque and differential limiting characteristics become opposite, thus enabling stable performance that allows each characteristic to be fully utilized. By separating the force-applying component 203 from the plate 45, the plate 45 with the second flat portion 41 and the force-applying component 203 that imparts the first contact force can be designed independently. Therefore, the structure is simplified, the degree of design freedom is increased, the setting and modification of characteristics are easier, and it can be constructed at low cost.

[0075] In this differential assembly 201, the force-applying member 203 is disposed between the differential housing 7 and the plate 45, and is supported radially by the differential housing 7. Each plate 45, forming a second flat portion 41 opposite to the first flat portion 39 of the pair of side gears 13, 15, is separately disposed from the force-applying member 103 as described above. Therefore, the plate 45 can be formed from a planar flat plate, which can suppress the structural complexity of the inner surface of the differential housing 7. An opening 47 is provided in the plate 45. The function of the opening 47 is the same as in the first embodiment.

[0076] By separating the force-applying member 203 from the plate 45, the plate 45 with the second flat portion 41 and the force-applying member 203, which imparts the first abutment force, can be designed independently. Therefore, the structure is simplified, design freedom is increased, and the setting and modification of characteristics are easier, allowing for low-cost construction. If the force-applying member 203 is appropriately positioned to abut against the differential housing 7 on the side of the plate 45 opposite to the pressing side, the deflection of the force-applying member 203 can be controlled, and the value of the initial torque and differential limiting characteristics can be easily managed. In this appropriate setting, other components such as the annular fulcrum member 57 of the first embodiment can also be configured, or protrusions or flat surfaces can be formed on the force-applying member 203 and the differential housing 7.

[0077] The above describes this embodiment, but this embodiment is not limited thereto, and various modifications can be made within the scope of the spirit of this embodiment.

[0078] For example, an oil groove is provided on the first flat surface and a friction element is provided on the second flat surface, but it is not limited to this. Any combination of friction element and oil groove, such as providing friction element or oil groove on both sides or providing friction element or oil groove on only one side, is also possible.

[0079] Furthermore, while disc springs are used in the force-applying components due to their efficient force application and space configuration, other elements can be utilized, taking into account their shape and number, as long as they are components that impart force. In the configuration relationship with the differential housing in this case, the selection of engagement positions and means, such as protrusions, holes, recesses, adhesives, welds, or the use of locking components, can be appropriately considered, taking into account the construction of the differential housing.

[0080] Symbol Explanation

[0081] 1, 101, 201—Differential assembly; 7—Differential housing; 11—Pin; 13, 15—Side gear; 29—Block component; 39—First flat part; 41—Second flat part; 43, 103, 203—Force-applying component; 45—Plate; 47—Opening; 51—Connecting part; 53—Pressing part; 59—Friction component.

Claims

1. A differential device, characterized in that, have: Differential housing, configured to rotate; The pinion is supported in the differential housing in a way that allows it to rotate on its own axis, and revolves around the differential housing as the differential housing rotates. as well as A pair of side gears that mesh with the pinion and are capable of rotating relative to it. The pinion and the side gear are composed of a bevel gear set. A first planar portion orthogonal to the rotation axis is provided on the back side of the gear portion of the side gear. The differential housing has a second planar portion that is orthogonal to the rotation axis and is positioned opposite to the first planar portion in a manner that allows it to abut against it. A first abutting force is applied between the first planar portion and the second planar portion by a force-applying component. The meshing reaction force between the pinion and the side gear imparts a second abutting force between the first planar portion and the second planar portion.

2. The differential device according to claim 1, characterized in that, The second flat portion is disposed on a plate, which is configured to rotate integrally with the differential housing. A connecting portion is provided on the inner diameter side of the first planar portion and the second planar portion, which connects the differential housing and the plate in a manner that allows them to rotate as a single unit.

3. The differential device according to claim 2, characterized in that, The force-applying component is formed from a component that is continuous with the plate, and the pressing portion that imparts the first abutment force is disposed on the outer diameter side of the connecting portion.

4. The differential device according to any one of claims 1 to 3, characterized in that, The first planar portion is disposed separately from the second planar portion in the direction of rotation axis from the inner end portion near the inner diameter side.

5. The differential device according to claim 2 or 3, characterized in that, The plate has an opening that extends through the axis of rotation.

6. The differential device according to claim 1 or 2, characterized in that, A block component is disposed between the pair of said side gears. The first abutting force of the force-applying component acts on the pair of side gears via the block component.

7. The differential device according to claim 2, characterized in that, The force-applying component is disposed between the differential housing and the plate.

8. The differential device according to claim 6, characterized in that, The force-applying component is disposed between at least one of the pair of side gears and the block component.

9. The differential device according to any one of claims 1 to 3, characterized in that, A friction element is provided on the surface of at least one of the first planar portion and the second planar portion.

10. The differential device according to any one of claims 1 to 3, characterized in that, An oil groove is provided on the surface of at least one of the first planar portion and the second planar portion.

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