JP2019078384A - Differential device for vehicle - Google Patents

Abstract

To provide a differential device for vehicle that stops a pinion shaft from coming out of a through hole when relatively large rotational torque is generated at the pinion shaft.SOLUTION: A first fixed member 32 and a second fixed member 34 has wall parts 32b, 34b made independent into regions where a pinion shaft 22 is stopped from coming out of through holes 12b, 12c, and engagement projection parts 32c, 34c made independent into regions where the pinion shaft 22 is stopped from rotating on a center axis C2, respectively, so even if relatively large rotational torque is generated at the pinion shaft 22 to cause the engagement projection part 32c of the first fixed member 32 and the engagement projection part 34c of the second fixed member 34 to be broken by an engaged part 22c of the pinion shaft 22, the wall part 32b of the first fixed member 32 and the wall part 34b of the second fixed member 34 can stop the pinion shaft 22 from coming out of through holes 12b, 12c.SELECTED DRAWING: Figure 1

Description

  According to the present invention, a pinion shaft inserted in a through hole formed in a differential case, a pinion gear accommodated in the differential case and supported rotatably around a central axis by the pinion shaft, and the pinion shaft as the differential case In a vehicle differential apparatus comprising: a fixing member fixed and preventing a removal of the pinion shaft from the through hole and a rotation member preventing rotation of the pinion shaft about the central axis, the pinion shaft is relatively fixed around the central axis. The present invention relates to a technique for preventing removal of the pinion shaft from the through hole even when a large rotational torque is generated and the fixing member is broken.

  (A) a differential case rotatably supported about one rotation axis, (b) a pinion shaft inserted in a through hole formed in the differential case, (c) housed in the differential case, the pinion shaft A pinion gear rotatably supported about a central axis orthogonal to the one rotation axis, and (d) the pinion shaft is fixed to the differential case, and the pinion shaft passes through the through hole and the center of the pinion shaft A differential device for a vehicle is known which comprises: a fixing member which prevents rotation about an axis. For example, the vehicle differential device described in Patent Document 1 is that. In the differential device for a vehicle of Patent Document 1, a shaft-side locking recess formed by recessing a part of an end surface of the pinion shaft on the case outer peripheral side of the differential case and a case outer peripheral surface of the differential case so as to pass through the shaft-side locking recess. An annular recess is formed, and an annular fixing member is resiliently fitted in the annular recess. In the vehicle differential device of Patent Document 1 configured as described above, the inner peripheral surface of the annular fixing member is on the shaft side of the pinion shaft by the annular fixing member abutting on the end of the pinion shaft. By the abutment of the locking recess and the abutment of the side surface of the annular fixing member with the side wall surface of the annular groove, the disengagement of the pinion shaft from the through hole and the rotation of the pinion shaft around the central axis are possible. It is supposed to be blocked.

JP-A-7-167253

  By the way, in the differential device for vehicles like patent document 1, the end part of the said pinion shaft is made to contact | abut to the said fixing member, the omission from the said through hole of the said pinion shaft and the said central axis line of the said pinion shaft. When the fixing member is broken, for example, a relatively large rotational torque around the central axis is generated in the pinion shaft due to, for example, seizure of the pinion shaft and the pinion gear. There was a concern that the shaft could get out of the through hole.

  The present invention has been made against the background described above, and the object of the present invention is for a vehicle that prevents removal of the pinion shaft from the through hole when a relatively large rotational torque is generated on the pinion shaft. To provide a differential device.

  According to a first aspect of the present invention, there is provided: (a) a differential case rotatably supported around one rotation axis, a pinion shaft inserted in a through hole formed in the differential case, and the differential case housed in the differential case; A pinion gear rotatably supported about a central axis orthogonal to the one rotation axis by the pinion shaft, and the pinion shaft are fixed to the differential case, and the pinion shaft passes through the through hole and the pinion shaft A differential device for a vehicle, comprising: a fixing member for preventing rotation around a central axis, wherein (b) the fixing member is connected to a base to be fastened to the differential case, and (c) to the base, the pinion (D) protruding into the through hole from the end of the wall, the wall being in contact with the end face of the shaft; Engaged portion formed on the side surface of the trunnion shaft and engage in include, the engaging projections to prevent rotation about the central axis of the pinion shaft.

  According to the first aspect of the invention, the fixing member projects into the through hole from the base fastened to the differential case, the wall connected to the base and abutting on the end face of the pinion shaft, and the tip of the wall. And an engagement protrusion which engages with an engaged portion formed on a side surface of the pinion shaft to prevent the pinion shaft from rotating about the central axis. As a result, the end face of the pinion shaft abuts against the wall portion of the fixed member to prevent the pinion shaft from coming off from the through hole, and the engaged portion of the pinion shaft is engaged with the fixed member The rotation of the pinion shaft about the central axis is blocked by coming into contact with the projection. Furthermore, in the fixing member, the wall portion may be a portion that prevents removal of the pinion shaft from the through hole, and the engagement protrusion may be a portion that prevents rotation of the pinion shaft about the central axis. Because they are independent, even if a relatively large rotational torque is generated in the pinion shaft and the engagement projection of the fixing member is broken by the engaged portion of the pinion shaft, the wall of the fixing member The part can prevent the pinion shaft from coming out of the through hole.

BRIEF DESCRIPTION OF THE DRAWINGS It is sectional drawing explaining the structure of the differential device for vehicles to which this invention was applied suitably. It is a perspective view explaining the structure of the 1st fixing member provided in the differential device for vehicles of FIG. 1, and a 2nd fixing member. It is a perspective view which shows the shape of the edge part of the pinion shaft provided in the differential device for vehicles of FIG. It is sectional drawing explaining the structure of an example of the conventional differential device for vehicles. It is a figure explaining the vehicle differential apparatus of the other Example of this invention.

  In the embodiment of the present invention, (a) the engaged portion formed on the side surface of the pinion shaft is formed by a plane perpendicular to the diameter of the pinion shaft and parallel to the central axis, (b) the differential case In order to fasten a ring gear, it has a flange portion provided on the outer peripheral side around the one rotation axis, and (c) the fixing member is bent from a single plate material to form the base portion, the wall portion And (d) the base portion is in the form of a disc having a central hole, and a fastening bolt for fastening the ring gear to the flange portion is passed through the central hole. (E) the wall portion has an arc-shaped cross section, and forms a partial cylindrical shape which protrudes in a direction parallel to the one rotation axis from a part of the outer peripheral edge of the base , The tip end of the arc The engagement projection is formed so as to reduce the circumferential length of the surface, and (f) the engagement projection is bent in a direction parallel to the central axis from the tip of the wall portion, and is formed on the side surface of the pinion shaft It is inserted between the engaging portion and the inner circumferential surface of the through hole. Therefore, the wall portion has an arc-shaped cross section, and forms a partial cylindrical shape which protrudes in a direction parallel to the one rotation axis from a part of the outer peripheral edge of the base, and the circumferential length of the arc-shaped cross section The engagement protrusion is bent in a direction parallel to the central axis from the tip of the wall portion, and the engaged portion formed on the side surface of the pinion shaft and the through hole are formed. In the fixing member, the strength of the wall portion is suitably larger than the strength of the engaging protrusion, and a relatively large rotational torque is generated in the pinion shaft. In this case, even if the engagement protrusion is broken, the wall portion is less likely to be broken. Further, the differential case has a flange portion protruding to the outer peripheral side around the one rotation axis to fasten a ring gear, the base is a disc having a central hole, and the ring gear is Since the fastening bolt to be fastened to the flange part is fastened to the flange part by penetrating the center hole, the ring gear and the fixing member can be fastened together to the differential case by the fastening bolt, for example, There is no need to add a fastening bolt separate from the fastening bolt in order to fasten the fixing member to the differential case.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In the following embodiments, the drawings are appropriately simplified or modified, and the dimensional ratios and shapes of the respective parts are not necessarily drawn accurately.

  FIG. 1 is a cross-sectional view of a differential device (vehicle differential device) 10 according to an embodiment of the present invention. The differential device 10 is a well-known differential gear device that transmits the driving force from a driving force source of a vehicle, such as an engine, to the pair of left and right wheels while allowing the rotational speed difference between the pair of left and right wheels.

  As shown in FIG. 1, the differential device 10 has a container-like differential case (differential case) 12 rotatably supported by a housing which is a non-rotational member (not shown) around a rotational axis (single rotational axis) C1 and a differential case 12. The ring gear 16 integrally fixed to the outer peripheral portion 12a of the first embodiment by a plurality of fastening bolts 14a and 14b etc., the cylindrical pinion shaft 22 inserted in the through holes 12b and 12c formed in the differential case 12, and the differential case 12 The pinion gears 18 and 20 rotatably supported about the central axis C2 orthogonal to the rotation axis C1 by the pinion shaft 22, and a pair of left and right side gears 24 and 26 meshing with the pinion gears 18 and 20, respectively. There is. The ring gear 16 is connected to a driving power source of the vehicle, such as an engine, so that power can be transmitted.

  As shown in FIG. 1, the differential case 12 includes a first case member 28 and a second case member 30. The first case member 28 has a cylindrical large diameter cylindrical portion 28a through which the aforementioned through holes 12b and 12c penetrate and an insertion hole through which a part of a drive shaft (not shown) connected by spline fitting to the side gear 26 is inserted. A cylindrical small diameter cylindrical portion 28c having a diameter smaller than that of the large diameter cylindrical portion 28a on which 28b is formed, an end portion of the small diameter cylindrical portion 28c on the second case member 30 side and a second case member 30 side of the large diameter cylindrical portion 28a And a flange-like flange 28e projecting from the end on the second case member 30 side of the large diameter cylindrical portion 28a to the outer peripheral side around the rotation axis C1. And are integrally provided. Further, the second case member 30 has a cylindrical cylindrical portion 30b formed with an insertion hole 30a through which a part of a drive shaft (not shown) connected by spline fitting to the side gear 24 is formed, and a second cylindrical member 30b A flange-like flange 30c is provided integrally with the end on the side of the case member 28 so as to protrude to the outer peripheral side around the rotation axis C1. The outer peripheral portion 12 a of the differential case 12 described above is formed by overlapping the flange portion 28 e of the first case member 28 and the flange portion 30 c of the second case member 30.

  In the differential device 10, as shown in FIGS. 1 and 2, the pinion shaft 22 is fixed to the differential case 12, and the through holes 12b and 12c formed in the differential case 12 of the pinion shaft 22 and the differential case of the pinion shaft 22. A pair of first fixing members (fixing members) 32 and a second fixing member (fixing members) 34 are provided to prevent the rotation of the motor 12 around the central axis C2 with respect to 12.

  As shown in FIGS. 1 and 2, the first fixing member 32 is connected to a base 32a fastened to the outer peripheral portion 12a of the differential case 12 by a fastening bolt 14a and the base 32a, and an end face of the pinion shaft 22 on the pinion gear 18 side. 22b engaged with the wall 22a and the through hole 12b formed in the differential case 12 from the end of the wall 32b and engaged with the engaged portion 22c formed on the side 22b of the pinion shaft 22 And a projection 32c. The second fixing member 34 has a base 34a fastened to the outer peripheral portion 12a of the differential case 12 by a fastening bolt 14b, and a wall 34b connected to the base 34a and abutting on an end face 22d of the pinion shaft 22 on the pinion gear 20 side. An engagement projection 34c is provided in the through hole 12c formed in the differential case 12 from the end of the wall portion 34b and is engaged with the engagement portion 22c of the pinion shaft 22. As shown in FIG. 2, the first fixing member 32 and the second fixing member 34 have the same shape, and the first fixing member 32 and the second fixing member 34 are a single plate material, for example, a metal. The base portions 32a and 34a, the wall portions 32b and 34b, and the engagement protrusions 32c and 34c are integrally provided by being bent from a plate or the like.

  As shown in FIG. 3, the engaged portion 22c formed on the side surface 22b of the pinion shaft 22 is formed by a surface 22e which is orthogonal to the diameter D of the pinion shaft 22 and parallel to the central axis C2. As shown in FIG. 1, the surface 22e formed on the pinion shaft 22 is formed from one end to the other end of the pinion shaft 22 in the longitudinal direction of the pinion shaft 22, and the side surface 22b of the pinion shaft 22 is A surface 22 f parallel to the surface 22 e formed on the pinion shaft 22 is formed.

  As shown in FIGS. 1 and 2, the base 32a of the first fixing member 32 is a disk having a central hole 32d, and the ring gear 16 is a flange of the first case member 28 which is the outer peripheral portion 12a of the differential case 12. A fastening bolt 14a fastened to the portion 28e and the flange portion 30c of the second case member 30 is fastened to the flange portions 28e and 30c by penetrating the center hole 32d. The base 34 a of the second fixing member 34 has a disk shape having a central hole 34 d, and fastens the ring gear 16 to the flange 28 e of the first case member 28 and the flange 30 c of the second case member 30. The fastening bolt 14b is fastened to the flanges 28e and 30c by penetrating the center hole 34d.

  As shown in FIG. 2, the wall 32 b of the first fixing member 32 and the wall 34 b of the second fixing member 34 each have an arc-shaped cross section, and a part of the outer periphery of the bases 32 a and 34 a, that is, the outer periphery It forms a partial cylindrical shape which protrudes in a direction parallel to the direction of the rotation axis C1 from a half circumferential portion of the above, and is formed such that the circumferential length L of the arc-shaped cross section decreases as the tip end.

  As shown in FIGS. 1 to 3, the engaging projection 32 c of the first fixing member 32 is bent in the direction parallel to the central axis C 2 from the tip of the wall 32 b and is formed on the side 22 b of the pinion shaft 22. It is inserted between the engaged portion 22c and the inner circumferential surface 12d of the through hole 12b. Further, the engagement projection 34c of the second fixing member 34 is bent in a direction parallel to the central axis C2 from the tip of the wall 34b, and is engaged with the engaged portion 22c formed on the side surface 22b of the pinion shaft 22. It is inserted between the inner circumferential surface 12e of the hole 12c.

  In the differential device 10 configured as described above, the end face 22a of the pinion shaft 22 abuts on the wall 32b of the first fixing member 32, and the end face 22d of the pinion shaft 22 contacts the wall 34b of the second fixing member 34. Since it contacts, the omission from the through holes 12b and 12c formed in the differential case 12 of the pinion shaft 22 is prevented. Further, since the engaged portion 22c of the pinion shaft 22 abuts on the engagement projection 32c of the first fixing member 32 and the engagement projection 34c of the second fixing member 34, the central axis of the pinion shaft 22 with respect to the differential case 12 Rotation around C2 is blocked.

  FIG. 4 is a cross-sectional view showing a conventional differential device 100. As shown in FIG. As shown in FIG. 4, in the differential device 100, the differential case 102 rotatably supported around the rotation axis C3 and the through holes 102a and 102b formed in the differential case 102 are inserted and accommodated in the differential case 102. A pinion shaft 108 rotatably supporting a pinion gear 104, 106 around a central axis C4 orthogonal to the rotation axis C3 and a pinion shaft 108 are fixed to the differential case 102, and the pinion shaft 108 passes through the through holes 102a, 102b and the pinion The fixing pin 110 which is a fixing member which blocks | prevents rotation of the central axis C4 of the shaft 108 is provided.

  In the conventional differential device 100 configured in this way, the fixing pin 110 prevents removal of the pinion shaft 108 from the through holes 102a and 102b and rotation of the pinion shaft 108 around the central axis C4, so that, for example, the pinion The pinion shaft 108 comes out of the through holes 102a and 102b when the fixing pin 110 is broken due to rotational torque around the relatively large central axis C4 generated in the pinion shaft 108 due to seizure of the shaft 108 and the pinion gears 104 and 106 or the like. There is a fear. Further, in the conventional differential device 100, in order to form the insertion hole 102c for inserting the fixing pin 110 in the differential case 102, it is necessary to make the thickness of the differential case 102 thicker than, for example, the differential case 12 of the differential device 10 of this embodiment. As a result, the weight of the differential case 102 or the differential device 100 is increased.

  However, in the differential device 10 of this embodiment, a relatively large rotational torque about the central axis C2 is generated in the pinion shaft 22 due to, for example, the seizure of the pinion shaft 22 and the pinion gears 18 and 20. Even if the engagement projection 32c of the first fixing member 32 and the engagement projection 34c of the second fixing member 34 are damaged by the engaged portion 22c, the wall portion 32b of the first fixing member 32 and the second fixing member The wall portion 34b of 34 can prevent the pinion shaft 22 from coming out of the through holes 12b and 12c.

  As described above, according to the differential device 10 of the present embodiment, the first fixing member 32 and the second fixing member 34 are respectively connected to the bases 32a and 34a fastened to the differential case 12 and the bases 32a and 34a. The wall portions 32b and 34b in contact with the end surfaces 22a and 22d of the pinion shaft 22, and the engagement portions formed on the side surface 22b of the pinion shaft 22 so as to protrude from the tips of the wall portions 32a and 34a into the through holes 12b and 12c. And engaging protrusions 32c, 34c that engage with the engaging portion 22c to prevent the pinion shaft 22 from rotating about the central axis C2. As a result, the end surfaces 22a and 22d of the pinion shaft 22 abut on the wall portion 32b of the first fixing member 32 and the wall portion 34b of the second fixing member 34, respectively, so that the pinion shaft 22 comes out of the through holes 12b and 12c. While being blocked, the engaged portion 22c of the pinion shaft 22 is in contact with the engagement projection 32c of the first fixing member 32 and the engagement projection 34c of the second fixing member 34, and the central axis C2 of the pinion shaft 22 Rotation around is blocked. Further, in the first fixing member 32 and the second fixing member 34, the wall portions 32b and 34b are prevented from coming off from the through holes 12b and 12c of the pinion shaft 22, and the engaging protrusions 32c and 34c are Therefore, a relatively large rotational torque is generated on the pinion shaft 22, and the first fixed member is engaged by the engaged portion 22c of the pinion shaft 22. Even if the engagement projection 32c of 32 and the engagement projection 34c of the second fixing member 34 are broken, the pinion shaft 22 is formed by the wall 32b of the first fixing member 32 and the wall 34b of the second fixing member 34. Can be prevented from coming out of the through holes 12b and 12c.

  Further, according to the differential device 10 of the present embodiment, (a) the engaged portion 22c formed on the side surface 22b of the pinion shaft 22 is a plane orthogonal to the diameter D of the pinion shaft 22 and parallel to the central axis C2. 22e, and (b) the differential case 12 has flange portions 28e and 30c provided on the outer peripheral side around the rotation axis C1 to fasten the ring gear 16; (c) the first fixing member 32 and the The two fixing members 34 are each bent from a single plate material and integrally include the bases 32a, 34a, the walls 32b, 34b, and the engaging projections 32c, 34c, and (d) the base 32a. , 34a is a disk having central holes 32d, 34d, and the fastening bolts 14a, 14b for fastening the ring gear 16 to the flanges 28e, 30c are central holes 32d, 34d. (E) wall portions 32b and 34b have an arc-shaped cross section and project from a part of the outer peripheral edge of the bases 32a and 34a in a direction parallel to the rotation axis C1. A partial cylindrical shape is formed, and the circumferential length L of the arc-shaped cross section becomes smaller toward the tip, and (f) the engaging protrusions 32c and 34c are parallel to the central axis C2 from the tips of the wall portions 32b and 34b It is bent in the following direction, and is inserted between the engaged portion 22c formed on the side surface 22b of the pinion shaft 22 and the inner peripheral surfaces 12d and 12e of the through holes 12b and 12c. Therefore, the wall portions 32b and 34b have an arc-shaped cross section, and form a partial cylindrical shape that protrudes in a direction parallel to the rotation axis C1 from a part of the outer peripheral edge of the bases 32a and 34a. The engagement protrusions 32c and 34c are bent in the direction parallel to the central axis C2 from the tips of the wall portions 32b and 34b, respectively, to form the side surfaces 22b of the pinion shaft 22. Since the formed engaged portion 22c and the inner peripheral surfaces 12d and 12e of the through holes 12b and 12c are inserted, the strengths of the wall portions 32b and 34b in the first fixing member 32 and the second fixing member 34 are obtained. Is suitably greater than the strength of the engaging projections 32c, 34c, and the wall sections 32b, 34c are damaged even if the engaging projections 32c, 34c are damaged when a relatively large rotational torque is generated in the pinion shaft 22. There is difficult to damage. Also, the differential case 12 has flange portions 28e and 30c protruding toward the outer periphery around the rotation axis C1 to fasten the ring gear 16, and the bases 32, 34 have a disk shape having central holes 32d and 34d. Since the fastening bolts 14a and 14b for fastening the ring gear 16 to the flanges 28e and 30c are passed through the center holes 32d and 34d by fastening them to the flanges 28e and 30c, the ring gear is engaged with the fastening bolts 14a and 14b. 16 and the first fixing member 32 and the second fixing member 34 can be fastened together to the differential case 12. For example, in order to fasten the first fixing member 32 and the second stationary member 34 to the differential case 12, fastening bolts 14a and 14b. There is no need to add a separate fastening bolt.

  Next, another embodiment of the present invention will be described. The same reference numerals are given to parts common to the above-described first embodiment and the description will be omitted.

  FIG. 5 is a view for explaining a differential device (vehicle differential device) according to another embodiment of the present invention. The differential device of the present embodiment is different from the differential device 10 of the first embodiment in that engaged portions 22c are formed only at both ends of the pinion shaft 22, and the others are the first embodiment. Is substantially the same as the differential device 10 of FIG.

  Although the embodiments of the present invention have been described in detail with reference to the drawings, the present invention is also applicable in other aspects.

  For example, in the differential device 10 of the first embodiment and the differential device of the second embodiment, the first fixing member 32 and the second fixing member 34 remove the pinion shaft 22 from the through holes 12 b and 12 c and the pinion shaft 22. The second fixing member 34 is configured to prevent rotation around the central axis C2, but one of the through holes, for example, the through hole 12c has a structure in which the pinion shaft 22 does not come out. You do not have to That is, one fixing member can prevent the removal of the pinion shaft 22 from the through hole 12 b and the rotation of the pinion shaft 22 around the central axis C2.

  In the first embodiment described above, the side surface 22b of the pinion shaft 22 has a surface 22e perpendicular to the diameter D of the pinion shaft 22 functioning as the engaged portion 22c and parallel to the central axis C2, and the surface 22e. Although the parallel surface 22f is formed, for example, the surface 22f may not be formed on the side surface 22b of the pinion shaft 22.

  Note that what has been described above is merely an embodiment, and the present invention can be implemented in variously modified and improved forms based on the knowledge of those skilled in the art.

10: Differential device (differential device for vehicle)
12: differential case 12b, 12c: through hole 18, 20: pinion gear 22: pinion shaft 22a, 22d: end face 22b: side 22c: engaged portion 32: first fixing member (fixing member)
32a: base 32b: wall 32c: engagement projection 34: second fixing member (fixing member)
34a: base 34b: wall 34c: engagement projection C1: rotation axis (one rotation axis)
C2: Central axis

Claims (1)

A differential case rotatably supported around one rotation axis, a pinion shaft inserted in a through hole formed in the differential case, and a central axis which is accommodated in the differential case and is orthogonal to the one rotation axis by the pinion shaft A pinion gear rotatably supported therearound; and a fixing member that fixes the pinion shaft to the differential case and prevents the pinion shaft from coming out of the through hole and the pinion shaft from rotating about the central axis. A vehicle differential device comprising:
The fixing member is
A base fastened to the differential case,
A wall connected to the base and in contact with an end face of the pinion shaft;
An engagement projection which projects from the end of the wall portion into the through hole and which engages with the engaged portion formed on the side surface of the pinion shaft to block the rotation of the pinion shaft around the central axis; ,
And a differential device for a vehicle.

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