JP2013181546A - Fastening structure and fastening method of annular member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the reliability of an integral product formed by fastening an annular member and a member to be fastened by press-fitting.SOLUTION: A wedge member 16 disposed between press-fitting surfaces 12a, 14a between a differential case 12 and a ring gear 14 receives a force Tof an axial direction between the differential case 12 and the ring gear 14 on its one slope 16a to divide the force Tof the axial direction in a radial direction. A force of the axial direction applied between the press-fitting surfaces 12a, 14a between the differential case 12 and the ring gear 14 is reduced. A rotation force P of a direction opposite to the radial direction as a component of a force of the radial direction increases surface pressure between the press-fitting surface 12a of the differential case 12 and a press-fitting surface 16b of the wedge member 16 and surface pressure between one slope surface 14a of the ring gear 14 and one slope surface 16a of the wedge member 16. Then, a, respectively, reaction force of the axial direction generated in each of press fitting surfaces 12a, 14a, 14e, 16a, 16b is increased as a whole (F+F).

Description

  The present invention relates to an annular member fastening structure and a fastening method.

Conventionally, a method of press-fitting an annular member into a separate member to be fastened to form an integral part has been widely used. As an example, a differential, differential case assembly, which is a component of an automobile drive system, is used. Assembling structure is mentioned. The differential case assembly 10 shown in FIG. 7A is configured by fastening a differential case (differential case) 12 and a ring gear 14. 7 (b), the cylindrical outer peripheral surface 12a of the differential case 12 and the inner peripheral surface 14a of the ring gear 14 serve as a press-fit surface, and the ring gear 14 is pressed into the differential case 12 in the axial direction. Thus, both are integrated. In this state, a reaction force P in the radial direction due to the press-fitting allowance is generated on the outer peripheral surface 12a of the differential case 12 and the inner peripheral surface 14a of the ring gear 14, and the axial friction force F = μP thereby causes both shafts The direction position is fixed.

Further, in order to more reliably position the ring gear 14 in the axial direction with respect to the differential case 12, a stopper portion 12b that protrudes annularly in the radial direction is formed on the proximal end side (right side in FIG. 7) of the differential case 12 in the axial direction. The one side surface 14b of the ring gear 14 is in contact with the stopper portion 12b. Further, the front end portion in the axial direction of the differential case 12 (the left end portion in FIG. 7) is caulked to constitute a caulking portion 12c, which is bitten into a notch 14d formed on the other side surface 14c of the ring gear 14 (for example, a patent) Reference 1). As shown in FIG. 8, the notches 14d are V-shaped concave portions formed at equal intervals in the circumferential direction at corners where the inner peripheral surface 14a of the ring gear 14 and the other side surface 14c intersect. is there. Therefore, the ring gear 14 press-fitted into the differential case 12 has its one side surface 14b regulated by the stopper portion 12b of the differential case 12, and the other side surface 14c regulated by the caulking portion 12c of the differential case 12, so that the axial and circumferential positions thereof are regulated. 12 and the ring gear 14 are positioned relative to each other.

European Patent Application No. 0647789

However, an axial force may be applied to the differential case 12 and the ring gear 14 by the force acting on the differential case assembly 10 during operation of the automobile. In particular, when the ring gear 14 is a helical gear, the torque T is applied to the ring gear 14 as shown in FIG. 7C, so that not only the meshing radial reaction force _Tr but also the meshing gear is engaged. A large thrust reaction force T _s is generated. At this time, the axial frictional force F = μP is generated on the outer peripheral surface 12a of the differential case 12 and the inner peripheral surface 14a of the ring gear 14 as described above. Here, as shown in FIG. 7C, when the torque T is a light load _TL , the frictional force F exceeds the meshing thrust reaction force Ts, and the axial direction between the differential case 12 and the ring gear 14 increases. Misalignment X does not occur. However, the torque T is, when a heavy load T _H as shown in FIG. 7 (d), the frictional force F is to exceed the frictional force F meshing thrust counterforces Ts occurs in press-fitting surface . The axial displacement X between the ring gear 14 and the differential case 12 due to the thrust reaction force due to the minute gap between the ring gear and the differential case due to the inevitable spring back of the caulking portion 12c of the differential case 12 (X> 0) is generated. Further, when the difference between the differential case 12 and the ring gear 14 is repeated, the press-fitting surfaces 12a and 14a between the ring gear 12 and the differential case 14 are worn, reducing the press-fitting allowance of both, reducing the surface pressure of the press-fitting surfaces 12a and 14a, The frictional force on the press-fitting surfaces 12a and 14a is reduced. Furthermore, by the reaction force F ₂ in the axial direction caused between the notches 14d of the crimping portion 12c and the ring gear 14 of the differential case 12, there is a risk of causing deformation to caulking portion 12c.

  The present invention has been made in view of the above problems, and the object of the present invention is to cause a force to act on an integrated product formed by fastening an annular member and a member to be fastened by press-fitting, thereby causing a shift between the two. This is to prevent the situation more reliably and to further improve the reliability of this integrated product.

(Aspect of the Invention)
The following aspects of the present invention exemplify the configuration of the present invention, and will be described separately for easy understanding of various configurations of the present invention. Each section does not limit the technical scope of the present invention, and some of the components of each section are replaced, deleted, or further while referring to the best mode for carrying out the invention. Those to which the above components are added can also be included in the technical scope of the present invention.

(1) An annular member, a fastened member that press-fits the annular member, and a wedge member that is a separate member from both the annular member and the fastened member, and the annular member is axial with respect to the fastened member An annular member fastening structure in which the wedge member is press-fitted into a press-fit surface between the annular member and the fastened member (Claim 1).
In the fastening structure of the annular member described in this section, the wedge member disposed between the press-fitting surfaces of the annular member and the fastening member has an axial direction between the annular member and the fastening member on the inclined surface. In response to the force, this axial force is divided in the radial direction. Then, the axial force applied between the press-fit surfaces of the annular member and the fastened member is reduced, and the radial component force is applied to the surface pressure (radial reaction in the press-fit surface of the annular member and the fastened member). As a result, the axial reaction force generated on each press-fitting surface is increased as a whole.

(2) In the above item (1), the wedge member has a single inclined surface with respect to a press-fitting direction of the annular member and the fastened member, and an inner peripheral surface of the annular member is provided with respect to the fastened member. An annular member fastening structure in which a single inclined surface having a complementary shape for receiving the wedge member is formed from the same direction as the press-fitting direction of the annular member (Claim 2).
In the fastening structure of the annular member described in this section, the one inclined surface with respect to the press-fitting direction of the annular member and the fastened member of the wedge member disposed between the press fitting surfaces of the annular member and the fastened member is annular. In response to an axial force between the member and the member to be fastened, the axial force is also divided in the radial direction. Thereby, the axial force in the direction of dropping the annular member from the fastened member is reduced, and the radial component force increases the surface pressure at the press-fitting surface between the annular member and the fastened member. And the axial reaction force which generate | occur | produces on the press-fit surface of an annular member and a to-be-fastened member is increased as a whole. As a result, the frictional force in the axial direction increases and the axial component force from the one inclined surface is also added, so that the sum of the frictional force and the axial component force exceeds the meshing thrust reaction force. Or avoiding a significant drop.

(3) In the above item (1), the wedge member has both inclined surfaces with respect to the press-fitting direction of the annular member and the fastened member, and the wedge member is received on the inner peripheral surface of the annular member. An annular member fastening structure in which both inclined surfaces having complementary shapes are formed.
In the fastening structure of the annular member described in this section, both inclined surfaces of the wedge member disposed between the press-fitting surfaces of the annular member and the fastened member with respect to the press-fitting direction of the annular member and the fastened member are annular. In response to an axial force between the member and the member to be fastened, the axial force is also divided in the radial direction. As a result, the axial force in the direction in which the annular member is detached from the fastened member and the opposite direction is reduced, and the radial component force reduces the surface pressure on the press-fitting surface between the annular member and the fastened member. Increase. And the axial reaction force which generate | occur | produces on the press-fit surface of an annular member and a to-be-fastened member is increased as a whole. As a result, the frictional force in the axial direction increases and the axial component force from both inclined surfaces is added, so that the sum of the frictional force and the axial component force exceeds the meshing thrust reaction force. Or avoiding a significant drop. In addition, since the inclined surfaces of the wedge member disposed between the press-fitting surfaces of the annular member and the fastened member with respect to the press-fitting direction of the annular member and the fastened member are both inclined surfaces, any of the axial directions The above-mentioned predetermined action is exhibited also in the direction of.

(4) A fastening structure for an annular member in which the wedge member is annular in the above items (1) to (3) (claim 4).
In the fastening structure of the annular member described in this section, the wedge member is formed in an annular shape, so that the entire press-fitting surface of the annular member and the member to be fastened is provided as described in (1) to (3) above. It has the effect of.
(5) The fastening structure of the annular member in which the wedge member is separated and arranged at a plurality of positions spaced in the circumferential direction in the above items (1) to (3).
In the fastening structure of the annular member described in this section, the wedge member is separately disposed at a plurality of positions spaced apart in the circumferential direction, so that the wedge member of the press-fitting surfaces of the annular member and the fastened member is arranged. The predetermined action described in the items (1) to (3) is exhibited at the place where the member is disposed.

(6) An annular member fastening structure according to (4) above, wherein the wedge member is divided into a plurality of portions in the circumferential direction.
In the fastening structure of the annular member described in this section, the wedge member is divided into a plurality of parts in the circumferential direction, so that the arrangement of the wedge member with respect to the press-fitting surface of the annular member and the fastening member is divided into the wedge members. This is done for each piece. Then, by combining each divided piece to constitute an annular wedge member, the entire press-fitting surface of the annular member and the fastened member is formed over the predetermined section described in (1) to (3) above. It has an effect.
(7) The fastening structure of the annular member according to (4), wherein the wedge member is elastic and has a C shape.
The annular member fastening structure described in this section is configured so that the wedge member is elastic and has a C shape, so that when the wedge member is disposed on the press-fitting surface of the annular member and the fastening member, the wedge member is The member is elastically deformed into a reduced diameter state, and the wedge member is inserted through the press-fitting surface located on the radially outer side. Then, the wedge member is temporarily fixed to the press-fitting surface by elastically returning the wedge member to the expanded diameter state. In this state, the wedge member is disposed on the press-fitting surface of the annular member and the fastened member by press-fitting the annular member and the fastened member. In this aspect, the predetermined action described in the above items (1) to (3) is exerted over almost the entire press-fitting surface of the annular member and the fastened member excluding the C-shaped cut portion of the wedge member. It is.

(8) A fastening structure of an annular member according to (1) to (7), wherein the wedge member is press-fitted between the press-fitting surfaces of the annular member and the fastened member (Claim 6).
In the fastening structure of the annular member described in this section, the wedge member is press-fitted between the press-fitting surfaces of the annular member and the fastening member, so that the wedge member is interposed between the annular member and the fastening member. However, a reaction force in the radial direction is generated due to the press-fitting allowance, thereby accelerating an increase in the axial frictional force.
(9) An annular member fastening structure according to (1) to (8) above, wherein the annular member is a ring gear and the member to be fastened is a differential case.
The fastening structure of the annular member described in this section exhibits the predetermined action described in the above items (1) to (8) by the wedge member disposed on the ring gear and the press-fitting surface of the differential case.

(10) A fastening structure of an annular member in which a flange is formed on the annular member in the items (1) to (9) (claim 8).
In the fastening structure of the annular member described in this section, torque is applied to the helical formed on the annular member, so that the press-fitting surfaces of the annular member and the fastened member are not only meshing radial but meshing. Thrust reaction force is generated. This meshing thrust reaction force is also divided in the radial direction on the slope of the wedge member disposed between the press-fitting surfaces of the annular member and the fastened member. The axial force applied between the press-fitting surfaces of the annular member and the fastened member is reduced, and the radial component force increases the surface pressure at the press-fitting surface of the annular member and the fastened member. The axial reaction force generated on the press-fitting surface is increased as a whole.

(11) A method for fastening an annular member and a fastened member into which the annular member is press-fitted, and simultaneously or when a ring gear as the annular member is press-fitted in an axial direction into a differential case as the fastened member. Later, a fastening method in which a wedge member is disposed between both press-fitting surfaces (claim 9).
In the fastening method described in this section, the wedge member disposed between the press-fitting surfaces of the ring gear and the differential case is inserted between the ring gear and the differential case at the same time or after press-fitting the ring gear in the differential case in the axial direction. In response to the axial force, the axial force is also divided in the radial direction. Then, the axial reaction force is reduced as a whole by reducing the axial force and increasing the surface pressure at the press-fitting surface between the ring gear and the differential case by the radial component force. It will increase.

(12) In the above (11), the wedge member is formed so as to have a single inclined surface with respect to the press-fitting direction of the ring gear and the differential case, and the inner surface of the ring gear is attached to the differential case. A single inclined surface having a complementary shape for receiving the wedge member is formed from the same direction as the press-fitting direction of the ring gear, and after the ring gear is press-fitted into the differential case, both the ring gear and the differential case are A fastening method in which the wedge member is disposed between the press-fitting surfaces (Claim 10).
In the fastening method described in this section, the one inclined surface of the wedge member arranged between the press-fitting surface of the ring gear and the differential case with respect to the press-fitting direction of the ring gear and the differential case is between the ring gear and the differential case. In response to the axial force, the axial force is also divided in the radial direction. The axial force in the direction of dropping the ring gear from the differential case is reduced, and the radial component force increases the surface pressure at the press-fitting surface between the ring gear and the differential case. And the axial reaction force which generate | occur | produces in a ring gear, a differential case, and a press-fit surface is increased as a whole. As a result, the frictional force in the axial direction increases and the axial component force from the one inclined surface is also added, so that the sum of the frictional force and the axial component force exceeds the meshing thrust reaction force. Or avoiding a significant drop.

(13) In the above (11), the wedge member is formed to have both inclined surfaces with respect to the press-fitting direction of the ring gear and the differential case, and the wedge member is formed on the inner peripheral surface of the ring gear. Forming both inclined surfaces having complementary shapes for receiving and arranging the inclined surfaces of the wedge member to coincide with the inclined surfaces of the ring gear, and then press-fitting the ring gear into the differential case. Then, the fastening method of disposing the wedge member between the press-fit surfaces of both the ring gear and the differential case (Claim 11).
In the fastening method described in this section, both inclined surfaces of the wedge member arranged between the press-fitting surfaces of the ring gear and the differential case with respect to the press-fitting direction of the ring gear and the differential case are provided between the ring gear and the differential case. In response to the axial force, the axial force is also divided in the radial direction. Thereby, the axial force in the direction in which the ring gear is dropped from the differential case and the opposite direction is reduced, and the radial component force increases the surface pressure at the press-fitting surface between the ring gear and the differential case. And the axial reaction force which generate | occur | produces on the press-fit surface of a ring gear and a differential case is increased as a whole. As a result, the frictional force in the axial direction increases and the axial component force from both inclined surfaces is added, so that the sum of the frictional force and the axial component force exceeds the meshing thrust reaction force. Or avoiding a significant drop. In addition, since the inclined surfaces of the wedge member disposed between the press-fitting surfaces of the annular member and the fastened member with respect to the press-fitting direction of the annular member and the fastened member are both inclined surfaces, any of the axial directions The above-mentioned predetermined action is exhibited also in the direction of.

(14) The fastening method according to (11) to (13) above, wherein the wedge member is formed in an annular shape (claim 12).
In the fastening method described in this section, the wedge member is formed in an annular shape, so that the predetermined action described in the above items (11) to (13) is achieved over the entire press-fitting surface of the ring gear and the differential case. It is.
(15) The fastening method according to (11) to (13) above, wherein the wedge member is separately arranged at a plurality of locations spaced in the circumferential direction.
In the fastening method described in this section, the wedge member is arranged separately at a plurality of locations spaced in the circumferential direction, so that the wedge member is disposed at the portion where the wedge member is disposed among the press-fitting surfaces of the ring gear and the differential case. The predetermined actions described in the items (11) to (13) are exhibited.

(16) The fastening method according to (11) to (13), wherein the wedge member is divided into a plurality of parts in the circumferential direction.
In the fastening method described in this section, since the wedge member is divided into a plurality of parts in the circumferential direction, the arrangement of the wedge member with respect to the press-fitting surface of the ring gear and the differential case is in order for each divided piece constituting the wedge member. To do. Then, by combining each divided piece to form an annular wedge member, over the entire press-fitting surface of the annular member and the fastened member, the predetermined items described in (11) to (13) above It has an effect.
(17) The fastening method according to the above items (11) to (13), wherein the wedge member is elastic and has a C shape.
In the fastening method described in this section, since the wedge member is elastic and has a C shape, the wedge member is reduced in diameter when the wedge member is disposed on the press-fitting surface of the ring gear and the differential case. The wedge member is inserted through a press-fitting surface that is elastically deformed toward the outside in the radial direction. Then, the wedge member is temporarily fixed to the press-fitting surface by elastically returning the wedge member to the expanded state. In this state, the wedge member is disposed on the press-fitting surface of the ring gear and the differential case by press-fitting the ring gear and the differential case. In this aspect, the predetermined action described in the above items (11) to (13) is achieved over substantially the entire press-fitting surface of the annular member and the fastened member excluding the C-shaped cut portion of the wedge member. It is.

(18) The fastening method according to (11) to (17), wherein the wedge member is press-fitted between the press-fitting surfaces of the ring gear and the differential case (claim 14).
In the fastening method described in this section, since the wedge member is press-fitted between the press-fitting surfaces of the ring gear and the differential case, the radial direction due to the press-fitting allowance also exists between the wedge member, the ring gear and the differential case. The reaction force is generated and the axial frictional force is increased accordingly.
(19) In the above (11) to (18), a fastening method is provided in which a ring is formed on the ring gear (claim 15).
In the fastening method described in this section, torque is applied to the helical formed on the ring gear, so that not only the meshing radial but also the meshing thrust reaction force is generated on the press-fit surfaces of the ring gear and the differential case. To do. This meshing thrust reaction force is also distributed in the radial direction on the slope of the wedge member disposed between the press-fit surfaces of the ring gear and the differential case. The axial force applied between the ring gear and the differential case between the press-fit surfaces is reduced, and the radial component force increases the surface pressure at the press-fit surface between the ring gear and the differential case. The generated axial reaction force is increased as a whole.

  Since the present invention is configured as described above, the force is applied to the integrated product formed by fastening the annular member and the member to be fastened by press-fitting, thereby preventing the occurrence of a shift between them more reliably. It is possible to further improve the performance.

It is sectional drawing which shows the component of the fastening structure of the annular member based on the 1st Embodiment of this invention. (A)-(e) is a fragmentary sectional view which shows the fastening procedure of the fastening structure of the annular member shown by FIG. FIG. 2 is a partial cross-sectional view illustrating a relationship between forces generated between an annular member and a member to be fastened in the fastening structure for the annular member shown in FIG. , (C) shows a heavy load. It is sectional drawing which shows the component of the fastening structure of the annular member based on the 2nd Embodiment of this invention. (A)-(e) is a fragmentary sectional view which shows the fastening procedure of the fastening structure of the annular member shown by FIG. FIGS. 5A and 5B are partial cross-sectional views illustrating a relationship between forces generated between the annular member and the fastened member in the fastening structure of the annular member shown in FIG. 4, and FIG. , (C) shows a heavy load. (A) is a schematic diagram which shows a differential case assembly as an example of the fastening structure of the conventional annular member, (a) at the time of no load, (b) at the time of light load, (c) at the time of heavy load, It is a fragmentary sectional view explaining the relationship of the force which arises between an annular member and a to-be-fastened member. FIG. 8 is a partial view of the ring gear shown in FIG. 7, (a) is a perspective view showing the notch, (b) is a front view of the notch, (c) is a cross-sectional view taken along line AA of (b), (d ) Is a sectional view taken along line BB in FIG.

The best mode for carrying out the present invention will be described below with reference to the accompanying drawings. In the following description, parts that are the same as or correspond to those in the prior art are assigned the same reference numerals, and detailed descriptions thereof are omitted.
FIG. 1 shows an example in which the annular member fastening structure according to the first embodiment of the present invention is employed in a differential case assembly 10 (see FIG. 7A). Also in this example, the cylindrical outer peripheral surface 12a of the differential case 12 and the inner peripheral surface 14a of the ring gear 14 serve as a press-fit surface, and the ring gear 14 is pressed into the differential case 12 in the axial direction so that they are integrated. It is what is done. Further, the differential case assembly 10 includes a wedge member 16 that is separate from both the ring gear 14 and the differential case 12. In the example of FIG. 1, the wedge member 16 has an annular shape. Then, the ring gear 14 is press-fitted in the axial direction with respect to the differential case 12, and the wedge member 16 is disposed between the press-fit surfaces 12 a and 14 a of the differential case 12 and the ring gear 14 to constitute the differential case assembly 10.

  1 has a press-fitting surface (16a, 16b) facing the press-fitting surface 12a of the differential case 12 and the press-fitting surface 14a of the ring gear 14, and the former is one side surface of the wedge member 16. It is formed as a single inclined surface 16a with respect to the press-fitting direction of the differential case 12 and the ring gear 14 in such a manner that the outer diameter increases from 16c toward the other side surface 16d. In addition, the part shown with the code | symbol 16e is the notch formed in the side surface 16d of the wedge member 16, and has the same shape as the notch 14d shown in FIG. On the other hand, on the inner peripheral surface 14a of the ring gear 14, the wedge member 16 is received at the intersection with the side surface 14c of the ring gear 14 from the same direction as the press-fitting direction of the ring gear 14 with respect to the differential case 12 (left direction in FIG. 1). A single inclined surface 14e having a complementary shape is formed. Moreover, the inclination angle and installation range of the single inclined surfaces 14e and 16e are set to a range suitable for producing the effects described below. The wedge member 16 is press-fitted between the press-fitting surfaces 12 a and 14 a of the differential case 12 and the ring gear 14. In addition, the ring gear 14 of FIG. 1 is formed with a helical 14f.

  FIG. 2 shows a procedure for press-fitting the ring gear 14 and the wedge member 16 into the differential case 12. First, the differential case 12 is fixed to a jig or the like, and as shown in FIG. 2A, the press-fitting surface 14a of the ring gear 14 is made to coincide with the press-fitting surface 12a of the differential case 12, and the side surface 14c of the ring gear 14 is set by a press machine or the like. Pressure. Then, as shown in FIG. 2B, the press-fitting operation of the ring gear 14 is continued until one side surface 14b of the ring gear 14 comes into contact with the stopper portion 12b. Subsequently, as shown in FIG. 2C, the press-fitting surface 12a of the differential case 12 and the press-fitting surface 16b of the wedge member 16 are made to coincide with each other, and pressure is applied to the side surface 14c of the ring gear 14 by a press machine or the like. . Then, as shown in FIG. 2D, the wedge member 16 is press-fitted until the one inclined surface 16a of the wedge member 16 comes into contact with the one inclined surface 14e formed on the press-fit surface 14a of the ring gear 14. to continue. Finally, as shown in FIG. 2 (e), the tip end portion in the axial direction of the differential case 12 is caulked to form the caulking portion 12 c and bite into the notch 16 e formed on the side surface 14 c of the wedge member 16. Complete the assembly work.

Now, according to the first embodiment of the present invention configured as described above, the following operational effects can be obtained. That is, as shown in FIGS. 3A to 3C, the wedge member 16 disposed between the press-fitting surfaces 12 a and 14 a of the differential case 12 and the ring gear 14 is formed on the single inclined surface 16 a with the differential case 12. by receiving the axial force T _s between the ring gear 14, also is a component force of the force T _s of the axial to the radial direction. Then, the axial force applied between the press-fit surfaces 12a and 14a of the differential case 12 and the ring gear 14 is reduced, and the radial reaction force P as a radial component force is applied to the press-fit surface 12a of the differential case 12. The surface pressure at the press-fitting surface 16b of the wedge member 16 and the surface pressure at the one inclined surface 14a of the ring gear 14 and the one inclined surface 16a of the wedge member 16 are increased. As a result, the axial reaction force (F + F _CS ) generated on the press-fitting surfaces 12a, 14a, 14e, 16a, and 16b can be increased as a whole.

As shown in FIG. 3B, when the torque T is a light load _TL , the axial frictional force F = μP is increased, and the axial direction from the one inclined surface 14a is increased. When the force F _{CS is} also applied, the sum of the friction force F and the axial component force F _CS exceeds the meshing thrust reaction force Ts, and the axial displacement X (X = 0) between the differential case 12 and the ring gear 14. ) Does not occur. Further, as shown in FIG. 3 (c), even when the torque T is heavy load T _H, the frictional force F = .mu.P the axial direction is increased, and the axial direction from the single inclined surface 14a also to join a larger reaction force F _CS of the sum of component force F _CS friction force F and the axial direction, meshing can be avoided far below the thrust reaction forces Ts. Therefore, even if an axial deviation X (X> 0) is generated between the ring gear 12 and the differential case 14 due to the inevitable minute gap between the ring gear 12 and the differential case 14, the amount of generation is small. It becomes possible to suppress.
Further, even if the shift between the ring gear 12 and the differential case 14 is repeated, the press-fitting surfaces 12a and 14a between the differential case 12 and the ring gear 14 are prevented from being worn, the press-fitting allowance of both is reduced, and the press-fitting surfaces 12a and 14a It is possible to avoid a decrease in the surface pressure and a decrease in the frictional force F on the press-fitting surfaces 12a and 14a. Then, the axial reaction force F ₂ (see FIG. 7D) generated between the caulking portion 12c of the differential case 12 and the notch 14d of the ring gear 14 can be reduced, and deformation of the caulking portion 12c can be avoided. Become.

  Since the wedge member 16 according to the first embodiment of the present invention has an annular shape, the press-fitting surfaces (12a, 14e, 16a, 16b) of the wedge member 16, the differential case 12, and the ring gear 14 are provided. As a whole, the above-mentioned predetermined effects are exhibited. However, as will be described later (see FIG. 4), the wedge member 16 may be divided into a plurality of parts in the circumferential direction. Moreover, even if the wedge member 16 is appropriately disposed separately at a plurality of positions spaced apart in the circumferential direction, the above-described predetermined effect can be obtained at the position where the wedge member is disposed.

In the first embodiment of the present invention, the wedge member 16 is press-fitted between the press-fitting surface 12a of the differential case 12 and the one inclined surface 14e formed on the press-fitting surface 14a of the ring gear 14. a wedge member 16, also between the differential case 12 and the ring gear 14, the reaction force P in the radial direction by the press-fitting margin occurs, are urging the reaction force F in the axial direction by which the increase of the F _CS. Further, the means for fixing the wedge member 16 to the differential case 12 and the ring gear 14 is also unnecessary. However, the wedge member 16 does not necessarily need to be press-fitted between the differential case 12 and the ring gear 14, and even if it is disposed between the differential case 12 and the ring gear 14, an axial component force F _CS Therefore, the axial reaction force (F + F _CS ) generated on each press-fitting surface can be increased as a whole.
In the first embodiment of the present invention, the ring gear 14 has the teeth 14f and the torque T is applied to the ring gear 14, so that not only the meshing radial reaction force _Tr but also the meshing thrust reaction. A case where the force T _s is generated is described as an example. However, even if the ring gear 14 is, for example, a spur gear, by adopting the configuration according to the first embodiment of the present invention, the same effect can be obtained when receiving some external force in the axial direction. It will be understood that

Next, a second embodiment of the present invention will be described with reference to FIGS. In the following description, the same or corresponding parts as those of the prior art and the first embodiment of the present invention are denoted by the same reference numerals, and detailed description thereof is omitted.
FIG. 4 also shows an example in which the annular member fastening structure according to the second embodiment of the present invention is employed in the differential case assembly 10 (see FIG. 7A). The wedge member 16 according to this example has a press-fit surface 12a of the differential case 12 and press-fit surfaces (16a ′, 16b) facing the press-fit surface 14a of the ring gear 14, and the former is a press-fit of the ring gear 14 to the differential case 12. Both inclined surfaces 16a ′ with respect to the direction are formed. Both inclined surfaces 16 a ′ are formed symmetrically in the axial direction with respect to the central portion in the axial direction of the wedge member 16. Further, in the example shown in the figure, the wedge member 16 is divided into a plurality of arcs (three divisions), and each piece is combined to form an annular shape as in the example of FIG.
On the other hand, both inclined surfaces 14 e ′ having a complementary shape for receiving the wedge member 16 are formed on the inner peripheral surface 14 a of the ring gear 14. In this example, a notch 14d is formed on the side surface 14c of the ring gear 14 as in the prior art (see FIG. 8). In addition, the inclination angle and the installation range of both inclined surfaces 14e 'and 16' are set to a range suitable for producing the effects described below. Both inclined surfaces 14e 'are formed in an axially symmetric shape with respect to the axial center portion of the ring gear 14 (intermediate portion between the side surfaces 14b and 14c).

FIG. 5 shows a procedure for press-fitting the ring gear 14 and the wedge member 16 into the differential case 12. First, as shown in FIG. 5 (a), both inclined surfaces 16a 'of the wedge member 16 are aligned with both inclined surfaces 14e' formed on the press-fitting surface 14a of the ring gear 14, and FIG. Temporarily assemble both as shown. At this time, the wedge members 16 are arranged on the inclined surfaces 14e 'of the ring gear 14 in order for each divided piece, and each divided piece is combined to form an annular shape. At this time, an adhesive or the like can be used to temporarily fix the wedge member 16 to the both inclined surfaces 14 e ′ of the ring gear 14. Alternatively, a jig may be used to bias the wedge member 16 against the ring gear 14 until the wedge member 16 contacts the press-fitting surface 12a of the differential case 12.

Further, the wedge member 16 may be configured as a C-shaped elastic member. In this case, when the wedge member 16 is disposed with respect to the both inclined surfaces 14e ′ of the ring gear 14, the wedge member 16 is elastically deformed into a reduced diameter state, and the press-fit surface 14a of the ring gear 14 located on the radially outer side. The wedge member 16 is inserted through the screw. Then, both the inclined surfaces 16a 'of the wedge member 16 are made to coincide with the both inclined surfaces 14e' formed on the press-fitting surface 14a of the ring gear 14, and the wedge member 16 is elastically returned to the expanded diameter state, thereby the wedge member. The wedge member 16 can be temporarily fixed to both inclined surfaces 14e ′ of the ring gear 14 using the elasticity of the ring gear 14.

Subsequently, the differential case 12 is fixed to a jig or the like, and as shown in FIG. 5C, the press-fit surface 14a of the ring gear 14 is made to coincide with the press-fit surface 12a of the differential case 12, and the side surface of the ring gear 14 is pressed by a press machine or the like. A pressure is applied to 14c. Then, as shown in FIG. 5D, the press-fitting operation of the ring gear 14 and the wedge member 16 is continued until one side surface 14b of the ring gear 14 comes into contact with the stopper portion 12b. Finally, as shown in FIG. 5 (e), the axial end portion of the differential case 12 is caulked to form a caulking portion 12c, which is bitten into a notch 14d formed on the side surface 14c of the ring gear 14, thereby assembling. Complete the work.

Now, according to the second embodiment of the present invention configured as described above, the following operational effects can be obtained. That is, as shown in FIGS. 6A to 6C, the wedge member 16 disposed between the press-fitting surfaces 12a and 14a of the differential case 12 and the ring gear 14 has a differential case 12 on both slopes 16a ′. and by receiving the axial force T _s between the ring gear 14, also is a component force of the force T _s of the axial to the radial direction. Then, the axial force applied between the press-fit surfaces 12 a and 14 a of the differential case 12 and the ring gear 14 is reduced, and the radial reaction force P is applied to the press-fit surface 12 a of the differential case 12 and the press-fit surface 16 b of the wedge member 16. By increasing the surface pressure and the surface pressure on both inclined surfaces 14a 'of the ring gear 14 and both inclined surfaces 16a' of the wedge member 16, shafts generated on the press-fitting surfaces 12a, 14a, 14e ', 16a', 16b. The direction reaction force (F + F _CS ) can be increased as a whole.

In addition, the above-described predetermined thrust reaction force Ts in the axial direction in the direction in which the ring gear 14 is removed from the differential case 12 (left direction in FIG. 6) and the opposite direction (right direction in FIG. 6). Thus, even when the direction of the meshing reaction force is generated in the direction opposite to that shown in FIG. 6, the same effect can be obtained. Further, both inclined surfaces 16 a ′ of the wedge member 16 according to the present example are formed symmetrically with respect to the axial center of the wedge member 16, and both inclined surfaces 14 e ′ of the ring gear 14 are formed on the ring gear 14. It is formed in an axially symmetrical shape with respect to the axially central portion (intermediate portion of the side surfaces 14b and 14c). Therefore, the same operational effects can be achieved for any meshing thrust reaction force Ts in the axial direction. However, it is also possible to give a difference to the effect obtained with respect to the opposite axial direction by making the inclination angles of the two inclined surfaces different as necessary.
In addition, detailed description of the same effects as those of the first embodiment of the present invention will be omitted.

As described above, in the embodiment of the present invention, a fastening including an annular member, a fastened member into which the annular member is press-fitted, and a wedge member which is a separate member from the annular member and the fastened member. As an example of the structure, the differential case assembly 10 is taken as an example. However, the application target of the present invention is not limited to this. For example, even when the annular member having the inner teeth is press-fitted into the inner surface of the cylindrical member to be fastened, the same effect is obtained. Will be understood.

10: differential case assembly, 12: differential case, 12a: outer peripheral surface (press-fit surface), 12b: stopper portion, 12c: caulking portion, 14: ring gear, 14a: inner peripheral surface (press-fit surface), 14b: one side surface, 14c: The other side surface, 14d: notch, 14e: one inclined surface (press-fit surface), 14e ': both inclined surfaces (press-fit surface), 16: wedge member, 16a: one inclined surface (press-fit surface), 16a': both inclined surfaces (press-fitting surface) 16b: press-fitting surface, 16c: one side, 16d: the other side, 16e: notch, F: frictional force, _{F 2:} reaction force in the axial direction, P: radial reaction forces, T, T _{L, T H:} torque, _{T r:} meshing radial reaction force, _{T s:} meshing thrust counterforces, mu: coefficient of friction

Claims (15)

An annular member, a fastened member that press-fits the annular member, and a wedge member that is a separate member from both the annular member and the fastened member,
The annular member fastening structure, wherein the annular member is press-fitted in the axial direction with respect to the fastened member, and the wedge member is disposed between the press-fitting surfaces of the annular member and the fastened member. . The wedge member has a single inclined surface with respect to the press-fitting direction of the annular member and the fastened member, and the inner peripheral surface of the annular member is from the same direction as the press-fitting direction of the annular member with respect to the fastened member. 2. A fastening structure for an annular member according to claim 1, wherein one inclined surface having a complementary shape for receiving the wedge member is formed. The wedge member has both inclined surfaces with respect to the press-fitting direction of the annular member and the member to be fastened, and both inclined surfaces having complementary shapes for receiving the wedge member on the inner peripheral surface of the annular member. The fastening structure for an annular member according to claim 1, wherein a surface is formed. The fastening structure for an annular member according to any one of claims 1 to 3, wherein the wedge member has an annular shape. The said wedge member is divided | segmented into multiple in the circumferential direction, The fastening structure of the annular member of Claim 4 characterized by the above-mentioned. 6. The annular member fastening structure according to claim 1, wherein the wedge member is press-fitted between press-fitting surfaces of the annular member and the fastened member. The said annular member is a ring gear, The said to-be-fastened member is a differential case, The fastening structure of the annular member of any one of Claim 1 to 6 characterized by the above-mentioned. The fastening structure for an annular member according to any one of claims 1 to 7, wherein a flange is formed on the annular member. A fastening method between an annular member and a member to be fastened to press-fit the annular member,
A fastening method, wherein a wedge member is disposed between both press-fitting surfaces at the same time or after press-fitting a ring gear as an annular member into the differential case as the fastened member. The wedge member is formed so as to have one inclined surface with respect to the press-fitting direction of the ring gear and the differential case, and the inner peripheral surface of the ring gear from the same direction as the press-fitting direction of the ring gear with respect to the differential case, Forming a canted surface having a complementary shape for receiving the wedge member;
The fastening method according to claim 9, wherein the wedge member is disposed between the press-fit surfaces of both the ring gear and the differential case after the ring gear is press-fitted into the differential case. The wedge member is formed so as to have both inclined surfaces with respect to the press-fitting direction of the ring gear and the differential case, and the inner peripheral surface of the ring gear has a complementary shape for receiving the wedge member. After forming an inclined surface and arranging so that both inclined surfaces of the wedge member coincide with both inclined surfaces of the ring gear,
The fastening method according to claim 9, wherein the wedge member is disposed between the press-fitting surfaces of both the ring gear and the differential case in the same step when the ring gear is press-fitted into the differential case. The fastening method according to claim 9, wherein the wedge member is formed in an annular shape. The fastening method according to any one of claims 9 to 12, wherein the wedge member is formed by being divided into a plurality of portions in the circumferential direction. The fastening method according to any one of claims 9 to 13, wherein the wedge member is press-fitted between press-fitting surfaces of the ring gear and the differential case. The fastening method according to claim 9, wherein the ring gear is formed with a flange.

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