JP2018146021A - Differential device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a differential device capable of reducing falling-down in an axial direction, of a side gear of a ring gear.SOLUTION: A differential device 11 includes a plurality of differential gears 32, a plurality of differential gear supporting members 34 respectively supporting one differential gear 32, a pair of output gears 33a, 33b respectively engaged with the plurality of differential gears 32, a supporting member 35 having a plurality of supporting portions 51 for supporting one end portion of each of the plurality of differential gear supporting members 34, and an input member 21 accommodating at least the supporting member 35, the plurality of differential gears 32 and the plurality of differential gear supporting members 34 inside. The supporting member 35 has a connecting portion 53 in which a radial outer end portion 53a kept into contact with an inner peripheral face of the input member 21, is divided into at least two, between two supporting portions 51 adjacent to each other.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a differential device mounted on a vehicle such as a four-wheeled vehicle.

  2. Description of the Related Art Conventionally, in a differential device, a technique for supporting one end of a short pinion shaft with a support member is known (for example, the second embodiment of Patent Document 1 and Patent Document 2).

Japanese Patent No. 516776 Japanese Patent No. 5167877

  However, in the techniques described in Patent Documents 1 and 2, when the shape of the differential device is changed from a spherical shape to another shape, such as flattening, the ring gear cannot withstand the load load, and the ring gear However, there is a possibility that the body gear may be bent such that it bends in the side gear side (in the axial direction of the side gear).

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a differential device that can reduce the fall of the ring gear in the axial direction of the side gear.

  To achieve the above object, one differential device according to the present invention includes a plurality of differential gears, a plurality of differential gear support members each supporting one differential gear, and the plurality of differential gears. A pair of output gears each meshing with the gear; a support member having a plurality of support portions for supporting one end of each of the plurality of differential gear support members; at least the support member; and the plurality of differential gears And an input member that accommodates the plurality of differential gear support members therein, and the support member is in contact with the inner peripheral surface of the input member between two adjacent support portions. The part has a connecting part that is divided into at least two parts.

  In order to achieve the above object, another differential device according to the present invention includes a plurality of differential gears having a convex portion at one end, and a pair of outputs that mesh with the plurality of differential gears, respectively. A gear, a support member having a plurality of support portions that support the convex portions of each of the plurality of differential gears, and an input member that accommodates at least the support member and the plurality of differential gears therein. The support member has a connecting portion in which a radially outer end portion that comes into contact with the inner peripheral surface of the input member is divided into at least two portions between two adjacent support portions.

  Preferably, the connecting portion has at least two radially outer end portions in a cross section taken along a virtual plane including a rotation axis of the output gear.

  Preferably, the connecting portion is in contact with the inner peripheral surface of the input member along a partial cylindrical surface coaxial with the rotation axis of the output gear.

  ADVANTAGE OF THE INVENTION According to this invention, the fall with respect to the axial direction of the side gear of a ring gear can be reduced.

It is sectional drawing which shows typically the whole structure of the differential gear which concerns on one Embodiment of this invention. It is a partial exploded perspective view of a differential. It is an expanded partial sectional view of a differential gear mechanism.

  Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

  FIG. 1 schematically shows the overall configuration of a differential 11 according to an embodiment of the present invention. The automobile is provided with a transmission case (not shown) disposed next to an engine (not shown) as a power source mounted on the automobile and accommodating a transmission (not shown) and the differential device 11. The transmission case 12 supports a pair of left and right output shafts 13a and 13b that are respectively connected to the axle so as to be rotatable about the central axis CL. The two output shafts 13 a and 13 b are arranged coaxially with each other and each have one end coupled to the differential device 11 in the mission case 12.

  Between the transmission case 12 and the individual output shafts 13a and 13b, annular seal members 14a and 14b are mounted. The seal members 14a and 14b liquid-tightly seal between the mission case 12 and the rotating output shafts 13a and 13b. In the present embodiment, an oil pan (not shown) that stores a predetermined amount of lubricating oil facing the internal space of the mission case 12 is formed at the bottom of the mission case 12. The lubricating oil stored in the oil pan is scooped up and scattered in the internal space of the mission case 12 by the rotation of the movable element of the reduction gear mechanism 16 and the differential case 15 described later. In this way, the mechanical motion portions existing inside and outside the differential case 15 described later are lubricated by the lubricant dispersed by the rotation of the movable element of the reduction gear mechanism 16 and the differential case 15 described later.

  The differential device 11 includes, for example, a differential case 15 that is supported by the transmission case 12 so as to be rotatable about a central axis CL, and a differential gear mechanism 17 that serves as a differential mechanism housed in the differential case 15.

  The differential case (case, input member) 15 includes, for example, a first cover member (one side surface) that covers one side surface (one side surface, the other side surface) of the differential gear mechanism 17 along a virtual plane orthogonal to the central axis CL. The other side surface (the other side surface) of the differential gear mechanism 17 facing the first cover member 18 along a virtual plane perpendicular to the central axis CL. The second cover member (the other cover member, the one cover member, the case, and the input member) 19 that covers one side surface, and the outer periphery of the first cover member 18 and the second cover member 19 are coupled to the first cover. And a ring member 21 that covers the differential gear mechanism 17 from a direction different from that of the member 18 and the second cover member 19 (outward in the radial direction of side gears 33a and 33b described later).

  Outward gear teeth 22 are provided on the outer peripheral surface of the ring member (driven member, case, input member) 21. The gear teeth 22 are arranged annularly coaxially with the central axis CL. Further, the gear teeth 22 of the ring member 21 mesh with the gear teeth 23 of the reduction gear mechanism 16. Therefore, engine power is transmitted from the transmission to the differential case 15. Therefore, the ring member 21 functions as a so-called ring gear (driven gear) and also functions as an input member. The ring member 21 covers one end (the other end) of a plurality of pinion shafts 34 described later.

  The first cover member 18 includes, for example, a first cover body 24 formed in a disc shape having a space in the center with the central axis CL as the center, and a second cover from the inner peripheral end of the first cover body 24. And a cylindrical first bearing portion (first boss portion) 25 that protrudes on the opposite side to the member 19 (the axial direction outward of side gears 33a and 33b described later).

  The second cover member 19 includes, for example, a second cover body 26 formed in a disc shape having a space in the center with the central axis CL as the center, and the first cover from the inner peripheral end of the second cover body 26. And a cylindrical second bearing portion (second boss portion) 27 protruding to the opposite side to the member 18 (the axial direction outward of side gears 33a and 33b described later).

  The differential gear mechanism 17 includes, for example, a plurality of pinion gears (differential gears) 32 that are rotatably supported around a rotation axis 31 that is orthogonal to the central axis CL, and a plurality of differential gear mechanisms 17 that are rotatably supported around the central axis CL. A pair of side gears (output gears) 33 a and 33 b (that is, a first side gear (first output gear) 33 a and a second side gear (second output gear) 33 b) that mesh with the pinion gear 32, and an axis coaxial with the rotation axis 31. And a plurality of pinion shafts (shafts, differential gear support members) 34 that rotatably support each pinion gear 32, and a support that supports the other end (one end) of each pinion shaft 34. Member 35.

  Each pinion gear 32 includes, for example, a support body 37 having a shaft hole 36 that rotatably receives the pinion shaft 34, and a gear tooth portion 38 that protrudes outward in the radial direction of the pinion gear 32 from the support body 37. The shaft hole 36 has, for example, a cylindrical shape. A plurality of gear teeth are annularly arranged around the axis of the pinion shaft 34 in the gear tooth portion 38.

  A slide surface 41 is formed on the back surface of the support 37 so as to spread from the periphery of the shaft hole 36 radially outward of the pinion gear 32 and be received by the receiving surface 39 on the inner periphery of the ring member 21. The slide surface 41 is constituted by a partial spherical surface having a center C on the central axis CL, for example. A washer (not shown) may be interposed between the receiving surface 39 of each ring member 21 and the slide surface 41 of the pinion gear 32.

  Each of the pair of side gears 33a and 33b includes, for example, a cylindrical shaft portion 43 having a shaft hole 42 into which the tip ends of the output shafts 13a and 13b are respectively spline-fitted, and the shaft portion 43 to the side gears 33a and 33b. Of the ring-shaped teeth 44 having gear teeth meshing with the plurality of pinion gears 32 at positions radially outward of the teeth, and teeth from the axially inward ends of the shaft 43 side gears 33a and 33b. An intermediate wall portion 45 formed in a flat plate shape extending outward in the radial direction of the side gears 33a and 33b toward the inner peripheral end portion of the portion 44. The relative rotation of the first side gear 33 a and the second side gear 33 b causes the pinion gear 32 to rotate around the rotation axis 31.

  The shaft portions 43 are covered with the corresponding first bearing portions 25 and second bearing portions 27, respectively. The output shafts 13a and 13b are fitted into the corresponding side gears 33a and 33b so as not to be relatively rotatable. In this way, the individual side gears 33a and 33b are rotatably supported by the bearings 46a and 46b via the differential case 15.

  The support member 35 includes, for example, a first main body portion 47 formed in an annular shape around the center axis CL, and a second main body portion 48 positioned radially outward of the side gears 33a and 33b with respect to the first main body portion 47. And having. In the present embodiment, the first main body portion 47 and the second main body portion 48 are integrally formed.

  Referring also to FIG. 2, the first main body portion 47 is, for example, a shaft that supports the other end portion (one end portion) of each of the plurality of pinion shafts 34 at equal intervals in the circumferential direction of the side gears 33 a and 33 b. A plurality of support portions 51 each having a hole 49 and a plurality of connection bodies (connection bodies) 52 that connect (connect) two adjacent support portions 51 are provided.

  For example, the second main body 48 is not formed radially outward of the support gear 51 of the first main body 47 and the side gears 33a and 33b around the support 51 (part of the coupling body 52). A plurality of connecting portions 53 are formed on the outer sides in the radial direction of the other side gears 33a and 33b of the first main body 47. That is, the second main body portion 48 has a plurality of connecting portions (connecting portions) 53 that are formed radially outward of the side gears 33 a and 33 b of some of the connecting bodies 52. Therefore, between the plurality of adjacent two connecting portions 53, that is, radially outward of the plurality of support portions 51 of the first main body portion 47 and the side gears 33a and 33b around the support portions 51, respectively. A space 54 that can accommodate the pinion gear 32 is formed.

  The connecting portion 53 has a radially outer end portion 53 a that is in contact with the inner peripheral surface of the ring member 21 and the radially outer end 53 aa of the connecting portion 53. The connection part 53 is divided into at least two or more in the cross section cut | disconnected by the virtual plane containing the central axis CL toward the radial direction outer end 53aa of the connection part 53. FIG. The connecting portion 53 is in a position separated from each other in the axial direction of the central axis CL (of the side gears 33a and 33b) and contacts the inner surface of the ring member 21 through a generatrix parallel to the central axis CL.

  The radially outer end portion 53a of the connecting portion 53 is, for example, a first portion extending in the circumferential direction around the central axis CL at a position away from the imaginary plane 56 including all the rotation axis 31 of the pinion gear 32 toward the first cover member 18 side. A first partial cylindrical body (partial cylindrical body, second partial cylindrical body) 57a and a second partial cylindrical body (partial) extending in the circumferential direction around the central axis CL at a position away from the virtual plane 56 toward the second cover member 19 side. A cylindrical body, a first partial cylindrical body) 57b and a concave portion 58 that is recessed between the first partial cylindrical body 57a and the second partial cylindrical body 57b so as to be separated from the inner surface of the ring member 21 and extend in the circumferential direction.

  The first partial cylindrical body 57a is, for example, a first partial cylindrical surface (second partial cylindrical surface, partial cylindrical surface) 59a extending outward in the circumferential direction around the central axis CL (axially outward in the side gears 33a and 33b). Have The first partial cylindrical body 57a is in surface contact with the first cover member 18 at the axially outer end 61a of the side gears 33a and 33b partitioned by a plane orthogonal to the central axis CL. The second partial cylindrical body 57b is, for example, a second partial cylindrical surface (first partial cylindrical surface, partial cylindrical surface) 59b that extends outward in the circumferential direction around the central axis CL (axially outward in the side gears 33a and 33b). Have The second partial cylindrical body 57b is in surface contact with the second cover member 19 at the axially outer end 61b of the side gears 33a and 33b partitioned by a plane orthogonal to the central axis CL.

  The inner surface (receiving surface 39) of the ring member 21 is centered at, for example, a first cylindrical surface 62a continuous in the circumferential direction around the central axis CL and a position away from the first cylindrical surface 62a in the axial direction of the central axis CL. Between the second cylindrical surface 62b that is continuous in the circumferential direction around the axis CL, and between the first cylindrical surface 62a and the second cylindrical surface 62b, the circumferential direction is continuous around the central axis CL, and the recess is separated from the central axis CL. And a curved concave surface 63 having a uniform cross-sectional shape in the circumferential direction. The first partial cylindrical surface 59a of the connecting portion 53 contacts the first cylindrical surface 62a of the ring member 21 by the surface. The second partial cylindrical surface 59b of the connecting portion 53 contacts the second cylindrical surface 62b of the ring member 21 by the surface. Thus, the connecting portion 53 contacts the inner peripheral surfaces (more specifically, the first cylindrical surface 62a and the second cylindrical surface 62b) of the ring member 21 at the partial cylindrical surfaces 59a and 59b in the axial direction of the central axis CL. Further, the slide surface 41 of the pinion gear 32 contacts the curved concave surface 63 of the ring member 21 with a line in an imaginary plane including the central axis CL.

  As shown in FIG. 3, the partial cylindrical bodies 57 a and 57 b are sandwiched between the first cover member 18 and the second cover member 19 in the axial direction of the central axis CL. The partial cylindrical surfaces 59a and 59b of the partial cylindrical bodies 57a and 57b define a generatrix 64 for each cross section cut along a virtual plane including the central axis CL. The first cylindrical surface 62a and the second cylindrical surface 62b of the ring member 21 define a generatrix 65 for each cross section cut along a virtual plane including the central axis CL. The connecting portion 53 contacts the ring member 21 at the bus bars 64 and 65. The outer peripheral surface 18a of the first cover member 18 and the outer peripheral surface 19a of the second cover member 19 are in contact with (contact with) the first cylindrical surface 62a and the second cylindrical surface 62b of the ring member 21, respectively.

  Next, the operation of this embodiment will be described. In the differential device 11 of the present embodiment, the pinion gear 32 does not rotate about the pinion shaft 34 when the differential case 15 receives rotational force from the engine via the reduction gear mechanism 16, and the central axis of the differential case 15 together with the differential case 15. (Rotation axis) When revolving around CL, the left and right side gears 33a and 33b are rotationally driven from the differential case 15 via the pinion gear 32 at the same speed, and the driving force of the side gears 33a and 33b is evenly distributed to the left and right output shafts 13a. , 13b. Further, when a difference in rotational speed occurs between the left and right output shafts 13a and 13b due to turning of the automobile or the like, the pinion gear 32 revolves around the central axis (rotation axis) CL of the differential case 15 while rotating so that the pinion gear 32 A rotational driving force is transmitted to the left and right side gears 33a and 33b while allowing differential rotation. The above is the same as the operation of a conventionally known differential.

  By the way, in assembling the differential device 11 of the present embodiment, for example, the ring member 21 is first coupled to the first cover member 18. In the joining operation, the ring member 21 is placed on the work table in a posture in which the central axis is orthogonal to the table surface, for example. The first cover member 18 is fitted inside the ring member 21 so that the first bearing portion 25 of the first cover member 18 is on the upper side. When fitted, the first cover member 18 is positioned at a predetermined position with respect to the axial direction of the ring member 21. After positioning, for example, the outer periphery of the first cover member 18 is welded to the ring member 21.

  Next, the combined body of the first cover member 18 and the ring member 21 is placed so that the first bearing portion 25 of the first cover member 18 is on the lower side and the first cover body 24 of the first cover member 18 is on the upper side. . Subsequently, a washer for the side gear 33a is disposed at an appropriate position on the first cover member 18 from above. Next, the first side gear 33 a is placed on the first cover body 24 of the first cover member 18. At this time, the shaft portion 43 of the first side gear 33 a is inserted into the first bearing portion 25 of the first cover body 24. The washer for the side gear 33a is positioned on the back surface of the tooth portion 44 of the first side gear 33a.

  Next, the pinion gear 32 and the pinion shaft 34 are mounted on the support member 35. In mounting, the pinion shafts 34 are inserted into the respective shaft holes 49 of the support member 35. The pinion gear 32 is inserted into each pinion shaft 34 inserted in the support member 35 so as to be displaceable in the axial direction of the pinion gear 32. When the pinion gear 32 is attached to the support member 35, the pinion gear 32 is accommodated in the space 54 of the support member 35.

  Next, the support member 35 is fitted inside the ring member 21. Prior to fitting, the pinion gear 32 is maximally pushed toward the shaft hole 36 of the support member 35. As a result, the distance from the central axis of the support member 35 to the slide surface 41 of the pinion gear 32 is smaller than the inner diameter of the ring member 21. In this way, the interference between the pinion gear 32 and the ring member 21 is avoided when fitting.

  When the support member 35 is fitted into the ring member 21, the radially outer end of the connecting portion 53 of the support member 35 with respect to the side gears 33a and 33b along the second cylindrical surface 62b and the first cylindrical surface 62a of the ring member 21. 53a slides. Then, the support member 35 is pushed into the ring member 21 until the axially outer end 61a of the first partial cylindrical body 57a of the connecting portion 53 with respect to the side gears 33a and 33b hits the first cover member 18. Further, the pinion gear 32 is moved to a predetermined position in the radial direction of the side gears 33a, 33b so that the individual pinion gears 32 are engaged with the teeth 44 of the first side gear 33a at a predetermined position in the radial direction of the side gears 33a, 33b. Then, the slide surface 41 of the pinion gear 32 is brought into contact with the receiving surface 39 of the ring member 21.

  Next, the second side gear 33 b is placed on the support member 35 so that the teeth 44 of the second side gear 33 b mesh with the plurality of pinion gears 32. Next, the washer for the side gear 33b is disposed on the second side gear 33b so as to be positioned on the back surface of the tooth portion 44 of the second side gear 33b. Then, the second cover member 19 is fitted inside the ring member 21 so that the second bearing portion 27 of the second cover member 19 is on the upper side. The second cover member 19 is pushed into the ring member 21 until it hits the axially outer end 61b of the connecting portion 53 with respect to the side gears 33a, 33b. When the second cover member 19 is completely fitted into the ring member 21, for example, the outer periphery of the second cover member 19 is welded to the ring member 21.

  According to the present embodiment, the support member 35 is in contact with the inner peripheral surface of the ring member 21 (the inner peripheral surface on the radial direction side of the support member 35 of the differential case 15) between two adjacent support portions 51. The radial outer end 53a of 35 (with respect to the side gears 33a and 33b) has a connecting portion 53 that is divided into at least two in the axial direction of the support member 35 (of the side gears 33a and 33b). The rigidity of the device 11 can be increased, and the inclination of the side gears 33a and 33b of the gear teeth 22 provided on the ring member 21 in the axial direction can be reduced.

  Further, according to the present embodiment, the connecting portion 53 has at least a radially outer end portion 53a of the side gears 33a and 33b in a cross section taken along a virtual plane including the rotation axes (that is, the central axis CL) of the side gears 33a and 33b. Divided into two. Thereby, the axial fall of the side gears 33a and 33b of the gear teeth 22 can be reduced. In addition, since the connecting portion 53 has the first and second partial cylindrical surfaces 59 a and 59 b of the first and second partial cylindrical bodies 57 a and 57 b of the side gears 33 a and 33 b abut against the inner peripheral surface of the ring member 21. It is also possible to prevent the gear teeth 22 from being displaced.

  Further, according to the present embodiment, the configuration of the first main body portion 47 and the connecting portion 53 of the support member 35 can increase the rigidity and strength of the ring member 21 that receives a driving force from the outside with the input gear teeth 22. .

  Further, according to the present embodiment, the radially outer end portion 53 a of the support member 35 of the connecting portion 53 is recessed between the bus bars 64 so as to be separated from the inner surface of the ring member 21 and extends in the circumferential direction of the support member 35. A recess 58 is formed. Thereby, weight reduction of the supporting member 35 is realizable.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to embodiment mentioned above, A various design change is possible in the range which does not deviate from the summary.

  For example, although the differential device 11 according to the present embodiment includes the pinion shaft 34 and the pinion gear 32 as separate bodies, the present invention is not limited to this. In the present invention, for example, a pinion gear integrated with a pinion shaft in which one end portion in the axial direction of the pinion gear becomes a shaft portion (convex portion) may be used. In other words, the shaft portion 132a of the pinion shaft integrated pinion gear 132 having the shaft portion (convex portion) 132a at one end portion is supported by the individual shaft holes of the support member, so that the above-described differential device is You may make it comprise.

  DESCRIPTION OF SYMBOLS 11 ... Differential gear, 15 ... Differential case (case, input member), 21 ... Ring member (driven member, ring gear, driven gear, case, input member), 32 ... Pinion gear (differential gear), 33a ... First side gear (side gear) , First output gear, output gear), 33b ... second side gear (side gear, second output gear, output gear), 34 ... pinion shaft (shaft, differential gear support member), 35 ... support member, 51 ... support portion 53a, a connecting portion, 53a, a radially outer end, 59a, a first partial cylindrical surface (partial cylindrical surface, second circular partial cylindrical surface), 59b, a second circular partial cylindrical surface (partial cylindrical surface, first part). (Cylindrical surface), 132... Pinion gear (differential gear), 132 a.

Claims (4)

A plurality of differential gears (32);
A plurality of differential gear support members (34) each supporting one said differential gear (32);
A pair of output gears (33a, 33b) each meshing with the plurality of differential gears (32);
A support member (35) having a plurality of support portions (51) for supporting one end of each of the plurality of differential gear support members (34);
An input member (21) for accommodating therein at least the support member (35), the plurality of differential gears (32), and the plurality of differential gear support members (34);
With
The support member (35) has at least two radially outer end portions (53a) that abut against the inner peripheral surface of the input member (21) between two adjacent support portions (51). Having a connecting part (53),
Differential device. A plurality of differential gears (132) having convex portions (132a) at one end;
A pair of output gears (33a, 33b) each meshing with the plurality of differential gears (132);
A support member (35) having a plurality of support portions (51) for supporting the convex portions (132a) of the plurality of differential gears (132);
An input member (21) for accommodating at least the support member (35) and the plurality of differential gears (132);
With
The support member (35) has at least two radially outer end portions (53a) that abut against the inner peripheral surface of the input member (21) between two adjacent support portions (51). Having a connecting part (53),
Differential device. The connecting portion (53) has a radially outer end portion (53a) divided into at least two sections in a cross section cut along a virtual plane including the rotation axis (CL) of the output gear (33a, 33b).
The differential device according to claim 1 or 2. The connecting portion (53) contacts the inner peripheral surface of the input member (21) along partial cylindrical surfaces (59a, 59b) coaxial with the rotation axis (CL) of the output gear (33a, 33b).
The differential apparatus of any one of Claims 1-3.