JP2017075649A - Intermediate shaft with dust cover - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a structure which can regulate the axial movement of a dust cover with respect to an objective split shaft without causing a weight increase of the objective split shaft (inner shaft) which is externally fit to the dust cover.SOLUTION: The axial movement of a dust cover 9 which is externally fit to an inner shaft 10 is regulated by a stopper ring 28 which is externally supported to the inner shaft 10. The displacement of the stopper ring 28 with respect to the inner shaft 10 is prevented by a screw stop of such a form that the inner shaft 10 is gripped between a tip of a screw 30 which is screwed into a screw hole existing at one point of the stopper ring 28 in a circumferential direction, and a portion located at a side opposite to the screw hole out of the stopper ring 28 in a radial direction.SELECTED DRAWING: Figure 1

Description

  The present invention constitutes a steering device and is disposed between an intermediate shaft disposed in a state of being inserted through a through hole provided in a dash panel of a vehicle body, and an outer peripheral surface of the intermediate shaft and an inner peripheral edge of the through hole The present invention relates to an intermediate shaft with a dust cover, which is combined with a dust cover for closing a gap.

  An automobile steering device is configured as shown in FIG. 6 (see, for example, Patent Document 1). The movement of the steering wheel 1 operated by the driver is transmitted to the input shaft 6 of the steering gear unit 5 via the steering shaft 2, the universal joint 3a, the intermediate shaft 4, and another universal joint 3b. As a result, the pair of left and right tie rods 7 and 7 are pushed and pulled by the rack and pinion mechanism built in the steering gear unit 5, so that the left and right pair of steered wheels correspond to the operation amount of the steering wheel 1. A rudder angle is given. In the illustrated steering device, an electric assist device is incorporated in which an assisting force corresponding to the force applied by the driver to the steering wheel 1 is applied to the steering shaft 2 by an electric motor 8.

  The intermediate shaft 4 is arranged in a state of being inserted through a through hole provided in a dash panel of the vehicle body. Such an intermediate shaft 4 includes a plurality of split shafts that are arranged coaxially and that are adjacent to each other in the axial direction and combined to enable torque transmission. Further, the target split shaft, which is any one of the split shafts, has an annular shape for closing a gap existing between the outer peripheral surface of the intermediate shaft 4 and the inner peripheral edge of the through hole. The dust cover is externally fitted.

  For the intermediate shaft with a dust cover, which is a combination of the intermediate shaft and the dust cover as described above, the dust cover moves in the axial direction until it is assembled to the vehicle body, and comes out of the target split shaft, Alternatively, it is preferable to have a configuration that can prevent damage from riding on a large-diameter male serration provided at the end of the target split shaft. For this purpose, for example, a locking groove extending over the entire circumference is formed in a portion of the target split shaft that is axially removed from a portion where the dust cover is fitted, and a retaining ring is provided in the locking groove. It is possible to adopt a configuration in which the dust cover is prevented from moving in the axial direction by bringing the dust cover into contact with the retaining ring when the dust cover moves in the axial direction. It is done. However, when such a configuration is adopted, the strength of the target split shaft is reduced at the portion where the locking groove is formed. Therefore, the strength should not be insufficient even at the portion where the strength is reduced. There is a possibility that the outer diameter of the entire target split shaft is increased, which increases the weight of the target split shaft.

JP 2015-21596 A

  In view of the circumstances as described above, the present invention provides a structure of an intermediate shaft with a dust cover that can regulate the axial movement of a dust cover that is externally fitted to the target split shaft without incurring the weight of the target split shaft. It was invented to realize.

An intermediate shaft with a dust cover according to the present invention constitutes a steering device and is arranged in a state of being inserted through a through hole provided in a dash panel of a vehicle body, an outer peripheral surface of the intermediate shaft, and an inside of the through hole And an annular dust cover used for closing a gap existing between the periphery.
Of these, the intermediate shaft has a plurality of split shafts that are coaxially arranged and combined adjacently in the axial direction to allow torque transmission.
The dust cover is externally fitted to a target split shaft, which is one of the split shafts.
Further, the dust cover has a shaft based on contact with an annular stopper ring that is externally supported by a portion of the target split shaft that is positioned on one side in the axial direction from a portion where the dust cover is externally fitted. Movement in one direction is restricted.
The stopper ring has a screw hole in a part in a circumferential direction, and is positioned on the opposite side of the screw hole in the radial direction with respect to the screw hole and the stopper ring screwed into the screw hole. The target split shaft is sandwiched between the parts to be separated (in other words, the target split by the tip of the screw and the part of the stopper ring that is located on the opposite side in the radial direction with respect to the screw hole) By the screwing of the aspect in which the outer peripheral surface of the shaft is gripped, movement in the axial direction relative to the target split shaft is prevented.

  When the intermediate shaft with a dust cover according to the present invention is implemented, for example, as in the invention described in claim 2, a portion in which serrations are not formed in the axial intermediate portion of the outer peripheral surface as the target split shaft The non-serrated portion is a male serrated portion having an outer diameter larger than the outer diameter of the non-serrated portion at one axial end adjacent to the one axial side of the non-serrated portion. When the dust cover is fitted on the male serration portion, and the stopper ring is moved to one side in the axial direction along the non-serration portion, the inner peripheral surface of the dust cover is the male serration. It can be provided at a position in contact with the dust cover prior to climbing on the part.

  When implementing the intermediate shaft with a dust cover of the present invention, for example, as in the invention described in claim 3, the non-serrated portion and the male serrated portion of the outer peripheral surface of the target split shaft are arranged on the stopper ring. Can be engaged with a stepped portion facing the other side in the axial direction.

  When the intermediate shaft with a dust cover according to the present invention is implemented, for example, as in the invention described in claim 4, the axially other side surface of the stopper ring is a portion in contact with the dust cover, and the stopper The other axial side surface of the ring can be arranged at the same axial position as the other axial end edge of the male serration portion.

When implementing the intermediate shaft with a dust cover of the present invention, the tip of the screw can be a pointed tip, as in the invention described in claim 5, for example.
In this case, for example, as in the invention described in claim 6, the pointed end portion of the screw is made harder than a portion of the outer peripheral surface of the target split shaft facing the pointed end portion, and the pointed end portion is In the outer peripheral surface of the target split shaft, it is possible to mechanically bite into a portion facing the pointed end portion.

When implementing the intermediate shaft with a dust cover according to the present invention, for example, as in the invention described in claim 7, a structure for preventing the screw from loosening with respect to the screw hole can be provided.
Examples of the locking structure include a structure in which the screw and the stopper ring are bonded and fixed, and a plastic deformation portion formed on at least one member of the screw and the stopper ring. A structure to be fitted, a structure in which a locking nut is screwed into a portion of the screw protruding from the outer peripheral surface of the stopper ring, or a washer is elastic between the head of the screw and the outer peripheral surface of the stopper ring. The structure etc. which are pinched | interposed to can be employ | adopted.

According to the intermediate shaft with a dust cover of the present invention configured as described above, the axial movement of the dust cover that is externally fitted to the target split shaft can be regulated without increasing the weight of the target split shaft. .
That is, in the case of the present invention, the dust cover is based on contact with a stopper ring that is externally supported by a portion of the target split shaft that is positioned on one side in the axial direction with respect to a portion where the dust cover is externally fitted. Therefore, movement to one side in the axial direction is restricted. The stopper ring can be prevented from moving in the axial direction with respect to the target split shaft. The screw hole of the stopper ring and the screw hole screwed into a screw hole existing in a part of the stopper ring in the circumferential direction. This is achieved by screwing in such a manner that the target split shaft is sandwiched between portions positioned on the opposite side in the radial direction. Therefore, in the case of the present invention, in order to prevent the stopper ring from moving in the axial direction with respect to the target split shaft, it is not necessary to provide a locking groove over the entire circumference on the outer peripheral surface of the target split shaft. . Therefore, with respect to the target split shaft, the outer diameter of the entire target split shaft is increased so that the portion provided with the locking groove does not have insufficient strength. Movement to one side can be restricted.

The partial cutting side view which shows the 1st example of embodiment of this invention. Sectional drawing (A) which expands and shows the a section of FIG. 1, and bb sectional drawing (B) of (A). The figure similar to (A) of Drawing 2 showing the 2nd example of an embodiment of the invention. The figure similar to (A) of Drawing 2 showing the 3rd example. The figure similar to FIG. 2 which shows the 4th example. The partially cut side view which shows an example of the steering apparatus known conventionally.

[First example of embodiment]
A first example of the embodiment of the present invention will be described with reference to FIGS.
The intermediate shaft with a dust cover of this example constitutes a sports car specification steering device, and is arranged in a state of being inserted through a through hole provided in a dash panel of a vehicle body, and an outer peripheral surface of the intermediate shaft 4a And an annular dust cover 9 used to close a gap existing between the inner periphery of the through hole and a stopper ring for restricting the axial movement range of the dust cover 9 relative to the intermediate shaft 4a 28.

  Among these, the intermediate shaft 4a and the front outer shaft 11 are the inner shaft 10 and the front outer shaft 11 which are a plurality of split shafts that are arranged coaxially and are combined in the axial direction so as to allow torque transmission. And a rear outer shaft 12.

  Of these, the inner shaft 10 that is the target split axis is a substantially cylindrical member made of steel. On the outer peripheral surface of such an inner shaft 10, a cylindrical surface portion 13 that is a non-serration portion is provided at an intermediate portion in the axial direction, a front male serration portion 14 is provided at a front end portion, and a rear male serration portion 15 is provided at a rear end portion. It is provided in a state adjacent to the axial direction. The outer diameters (diameters of circumscribed circles of the convex portions) of the front and rear male serration portions 14 and 15 are slightly larger than the outer diameter of the cylindrical surface portion 13 (for example, about 0.3 to 2 mm). . In the case of this example, the front male serration portion 14 corresponds to the serration portion described in the claims. In addition, such an inner shaft 10 forms the male side serrations 14 and 15 on the front side and the rear side by performing a rolling process on both ends in the axial direction of the bowl-shaped member having a total length of a predetermined rolling lower diameter. Built.

  The front outer shaft 11 is a substantially circular tubular member made of steel. A female serration portion 16 is provided in the rear half of the inner peripheral surface of the front outer shaft 11. In addition, an axial slit 17 is provided at one place in the circumferential direction of the rear half of the front outer shaft 11 so that the rear half of the front outer shaft 11 can be elastically expanded and contracted. Further, a pair of flange portions 18 and 18 are provided at two positions on the outer peripheral surface of the front outer shaft 11 with the axial slit 17 sandwiched from both sides in the circumferential direction. In addition, a through hole 19 and a screw hole 20 are provided in a portion where the flange portions 18 and 18 are aligned with each other. The male screw portion of the bolt 21 inserted through the through hole 19 is screwed into the screw hole 20. Further, the base portion of the rear yoke 22 constituting the front universal joint 3b (see FIG. 6) is coupled to the front end portion of the front outer shaft 11 so as to transmit torque. In addition, the front portion of the front male serration portion 14 of the inner shaft 10 is in serration engagement (engaged so as to be able to transmit torque) to the female serration portion 16. When the bolt 21 is tightened in this state, the female serration portion 16 and the front male male portion 16 and the front male male portion 16 are elastically reduced in diameter based on the presence of the axial slit 17. The serration portion 14 is strongly frictionally engaged, and the axial sliding between the two serration portions 14 and 16 is prevented. On the other hand, when the bolt 21 is loosened, a frictional engagement force between the female serration portion 16 and the front male serration portion 14 is obtained as the rear half portion of the front outer shaft 11 is elastically restored and expanded in diameter. Is lowered, and axial sliding between the two serration portions 14 and 16 is allowed. With this configuration, when the intermediate shaft 4a is assembled to the vehicle body, the bolt 21 is loosened so that the position of the front outer shaft 11 in the axial direction relative to the inner shaft 10 can be adjusted. The bolt 21 is tightened at the time of conveyance before being assembled to the body or after being assembled to the vehicle body, so that relative displacement in the axial direction between the inner shaft 10 and the front outer shaft 11 can be prevented.

  The rear outer shaft 12 is a substantially tubular member made of steel. A female serration portion 23 is provided at the front end portion of the inner peripheral surface of the rear outer shaft 12. Further, a base portion of a front yoke 24 constituting the rear universal joint 3a (see FIG. 6) is coupled to the rear end portion of the rear outer shaft 12 by an elastic shaft joint structure so as to transmit torque. ing. In addition, the entire rear male serration portion 15 of the inner shaft 10 is engaged with the female serration portion 23 (engaged so that torque can be transmitted). Further, in this state, the front end portion of the rear outer shaft 12 is pressed and plastically deformed by a pair of jigs sandwiched from both sides in the radial direction, and the female serration portion 23 and the rear male portion are formed by the plastic deformation portion. The serration portion 15 is strongly frictionally engaged. With such a configuration, in a normal state, the female serration portion 23 and the rear male serration portion 15 do not slide in the axial direction, but an axial impact force is applied to the plastic deformation portion by a primary collision. Is applied, the rear end portion of the inner shaft 10 is pushed into the rear outer shaft 12 against the frictional engagement force in the plastic deformation portion, so that the impact force can be reduced. It has become.

  The dust cover 9 includes a cover body 25 and a seal member 26. Among these, the cover main body 25 is made of a synthetic resin in an annular shape, and includes a cylindrical portion 27 at the radially inner end. The seal member 26 is made of a rubber cylinder and has a radially outer half that is formed in the axially intermediate portion of the inner peripheral surface of the cylindrical portion 27 over the entire circumference. It is held and fixed inside. Such a dust cover 9 is fitted on the cylindrical surface portion 13 of the inner shaft 10. In this state, the inner peripheral surface of the seal member 26 is in elastic contact with the cylindrical surface portion 13 over the entire circumference, and both axial ends of the inner peripheral surface of the cylindrical portion 27 are in the cylindrical shape. The surface portion 13 is in proximity or lightly in contact. In this state, the dust cover 9 can be moved in the axial direction along the cylindrical surface portion 13 (sliding in the axial direction of the seal member 26 with respect to the cylindrical surface portion 13). Accordingly, the axial position of the dust cover 9 with respect to the cylindrical surface portion 13 can be adjusted when assembled to the vehicle body. In the case of this example, a cut (not shown) is provided at one place in the circumferential direction of the dust cover 9 (the cover body 25 and the seal member 26), and by expanding the width of the cut elastically, The cylindrical surface portion 13 can be inserted into the inner diameter side of the dust cover 9 through the portion between the cuts. Further, when the dust cover 9 is in a free state (elastically restored state), the width of the cut becomes substantially zero.

  The stopper ring 28 is formed in an annular shape having a rectangular cross section by a material having a required strength, such as a metal such as an iron-based alloy or an aluminum alloy, or a fiber-reinforced plastic. The inner diameter of the stopper ring 28 is slightly larger than the outer diameters of the front and rear male serration portions 14 and 15 of the inner shaft 10. Further, a screw hole 29 penetrating in the radial direction is provided at one central portion in the circumferential direction of the stopper ring 28. Such a stopper ring 28 is externally supported by a portion near the front end of the cylindrical surface portion 13, which is a portion of the cylindrical surface portion 13 of the inner shaft 10 that is positioned in front of the portion where the dust cover 9 is externally fitted. Has been. For this purpose, specifically, the stopper ring 28 is loosely fitted to the front end portion of the cylindrical surface portion 13 through the front end portion or the rear end portion of the inner shaft 10 and then screwed into the screw hole 29. By tightening the screw 30, the cylindrical surface portion 13 is strongly clamped between the tip portion of the screw 30 and a portion of the stopper ring 28 located on the opposite side in the radial direction with respect to the screw hole 29. Stopping. Thereby, the shaft of the stopper ring 28 with respect to the cylindrical surface portion 13 is formed by strongly frictionally engaging the tip surface of the screw 30 and the inner peripheral surface of the stopper ring 28 with both side portions in the radial direction of the cylindrical surface portion 13. The movement of the direction is prevented. In the illustrated example, the inner surface of the head 31 of the screw 30 (the lower surface of FIGS. 1 and 2A) is the outer periphery of the stopper ring 28 with the screw 30 tightened as described above. Although the surfaces are brought into contact, when the present invention is carried out, it is not necessary to bring these two surfaces into contact with each other.

  In the case of this example, the screw 30 is bonded and fixed to the stopper ring 28 with an adhesive such as a screw lock agent previously applied to the screw 29 with the screw 30 tightened as described above. By doing so, the screw 30 is prevented from loosening. When the present invention is carried out, the structure for preventing the screw 30 from loosening is formed, for example, on at least one member of the screw 30 and the stopper ring 28 in addition to the structure for adhesively fixing as described above. A structure in which the plastic deformation portion (caulked portion) is engaged with the other member, a structure in which a locking nut is screwed into a portion of the screw 30 protruding from the outer peripheral surface of the stopper ring 28 and tightened, A structure or the like in which a washer is elastically sandwiched between the head 31 of the screw 30 and the outer peripheral surface of the stopper ring 28 can be employed.

  In any case, in the case of this example, by providing the stopper ring 28 as described above, when transporting the intermediate shaft with the dust cover before being assembled to the vehicle body, the intermediate shaft with the dust cover is attached to the vehicle body. When the dust cover 9 is moved forward along the cylindrical surface portion 13 of the inner shaft 10 during assembly, the front end surface of the cylindrical portion 27 constituting the dust cover 9 is located on the rear side surface of the stopper ring 28. Based on the contact, the dust cover 9 is further prevented from moving forward, and the inner peripheral surface of the seal member 26 constituting the dust cover 9 is in contact with the outer peripheral surface of the front male serration portion 23. I try to be able to prevent getting on (and getting damaged after getting on). In the case of this example, the adjustable range of the axial position of the dust cover 9 relative to the cylindrical surface portion 13 of the inner shaft 10 is such that the front end surface of the cylindrical portion 27 constituting the dust cover 9 is the rear side surface of the stopper ring 28. From the position in contact with the rear end surface of the cylindrical portion 27 to the position in contact with the front end surface of the rear outer shaft 12.

According to the intermediate shaft with the dust cover of the present example configured as described above, the movement of the dust cover 9 fitted on the inner shaft 10 in the axial direction (forward) is performed without increasing the weight of the inner shaft 10. Movement) can be regulated.
That is, in the case of this example, the dust cover 9 is externally supported by a portion of the cylindrical surface portion 13 of the inner shaft 10 that is externally supported by a portion located on the front side of the portion where the dust cover 9 is externally fitted. The movement to one side in the axial direction is restricted based on the contact with the rear side surface of 28. Further, the stopper ring 28 is prevented from moving in the axial direction with respect to the inner shaft 10. The stopper ring 28 and the tip of the screw 30 screwed into a screw hole 29 existing in one circumferential direction of the stopper ring 28 and the stopper ring 28. Of these, the inner shaft 10 is clamped between the screw hole 29 and a portion located on the opposite side in the radial direction. Therefore, in the case of this example, in order to prevent the stopper ring 28 from moving in the axial direction with respect to the inner shaft 10, it is necessary to provide a locking groove on the entire outer periphery of the inner shaft 10. Absent. Therefore, with respect to the inner shaft 10, the outer diameter of the inner shaft 10 is increased so that the portion provided with the locking groove does not have insufficient strength. The movement to can be regulated.

[Second Example of Embodiment]
A second example of the embodiment of the present invention will be described with reference to FIG.
In the case of this example, the position where the stopper ring 28 is externally fitted and supported with respect to the inner shaft 10 is slightly shifted forward from the case of the first example of the above-described embodiment. Accordingly, in the case of this example, the portion of the front side surface of the stopper ring 28 that is located on the opposite side of the screw hole 29 in the radial direction is the cylindrical surface portion 13 and the front male serration of the outer peripheral surface of the inner shaft 10. It is made to contact | abut (engage) the step part 32 which exists in the continuous part with the part 14, and turned to the rear side. Such a stepped portion 32 preferably exists on a virtual plane orthogonal to the axial direction of the inner shaft 10.
According to such a structure of this example, even when the front end surface of the cylindrical portion 27 (see FIG. 1) constituting the dust cover 9 bumps against the rear side surface of the stopper ring 28, the stopper ring 28 and By the engagement with the stepped portion 32, the stopper ring 28 can be hardly displaced forward. Further, the adjustable range of the axial position of the dust cover 9 with respect to the cylindrical surface portion 13 of the inner shaft 10 is widened by the amount of shifting the position where the stopper ring 28 is externally fitted and supported with respect to the inner shaft 10. I can do things.
Other configurations and operations are the same as those in the first example of the embodiment described above.

[Third example of embodiment]
A third example of the embodiment of the present invention will be described with reference to FIG.
Also in the case of this example, the position where the stopper ring 28 is externally supported with respect to the inner shaft 10 is shifted further forward than in the case of the first example of the embodiment described above. Specifically, the stopper ring 28 is externally supported on the rear end portion of the front male serration portion 14 of the inner shaft 10, and the rear side surface of the stopper ring 28 {the cylindrical portion 27 constituting the dust cover 9 ( 1) is arranged at the same axial position as the rear end edge (step 32) of the front male serration portion 14.
According to such a structure of this example, the cylindrical portion 27 and the seal member 26 (see FIG. 1) constituting the dust cover 9 are within the range where they do not ride on the outer peripheral surface of the front male serration portion 14. The adjustable range of the axial position of the dust cover 9 relative to the cylindrical surface portion 13 of the shaft 10 can be maximized.
Other configurations and operations are the same as those in the first example of the embodiment described above.

[Fourth Example of Embodiment]
A fourth example of the embodiment of the present invention will be described with reference to FIG.
In the case of this example, the tip of the screw 30a is a pointed tip 33 having a pointed conical shape. Further, the pointed end portion 33 is harder than the portion of the outer peripheral surface of the inner shaft 10 that faces the pointed end portion 33. For this reason, in the case of this example, the screw 30a is made of steel, and at least the pointed end portion 33 of the screw 30a is subjected to hardening heat treatment. The pointed portion 33 is mechanically bitten into the outer peripheral surface of the inner shaft 10 with the screw 30a tightened.
According to such a structure of the present example, the pointed portion 33 mechanically bites into the outer peripheral surface of the inner shaft 10, so that the displacement of the stopper ring 28 with respect to the inner shaft 10 is further less likely to occur.
Other configurations and operations are the same as those in the first example of the embodiment described above.

  In addition, the structure which makes the pointed part of a screw | thread as mentioned above mechanically bite into the outer peripheral surface of an inner shaft is applicable also to the structure of the 2nd-3rd example of embodiment mentioned above. When applied to the structure of the third example of the embodiment, it is preferable that the tip of the screw is bitten into the groove portion of the front male serration portion 14 in terms of ease of application.

DESCRIPTION OF SYMBOLS 1 Steering wheel 2 Steering shaft 3a, 3b Universal joint 4, 4a Intermediate shaft 5 Steering gear unit 6 Input shaft 7 Tie rod 8 Electric motor 9 Dust cover 10 Inner shaft 11 Front outer shaft 12 Rear outer shaft 13 Cylindrical surface part 14 Front male serration Part 15 Rear male serration part 16 Female serration part 17 Axial slit 18 Flange part 19 Through hole 20 Screw hole 21 Bolt 22 Yoke 23 Female serration part 24 York 25 Cover body 26 Seal member 27 Cylindrical part 28 Stopper ring 29 Screw hole 30 30a Screw 31 Head 32 Step 33 Pointed end

Claims (7)

A steering device is configured, and an intermediate shaft arranged in a state of being inserted through a through hole provided in a dash panel of a vehicle body, and a gap existing between an outer peripheral surface of the intermediate shaft and an inner peripheral edge of the through hole are blocked. With an annular dust cover used for
Each of the intermediate shafts has a plurality of split shafts that are arranged coaxially and combined in a manner that allows torque transmission between adjacent ones in the axial direction.
The dust cover is externally fitted to a target split shaft, which is one of the split shafts.
The dust cover is axially single-sided based on contact with an annular stopper ring that is externally supported by a portion of the target split shaft that is positioned axially one side of the portion where the dust cover is externally fitted. Is restricted from moving to
The stopper ring has a screw hole in a part in the circumferential direction, and a portion of the stopper ring that is screwed into the screw hole and a part of the stopper ring that is located on the opposite side in the radial direction with respect to the screw hole. The intermediate shaft with a dust cover is designed to prevent movement in the axial direction with respect to the target split axis by screwing the target split axis between the two. The target split shaft has an outer diameter larger than the outer diameter of the non-serrated portion at the axially intermediate end portion of the outer peripheral surface, and at one axial end portion adjacent to one axial side of the non-serrated portion. Each having a male serration portion having
The dust cover is externally fitted to the non-serrated portion,
The stopper ring contacts the dust cover before the inner peripheral surface of the dust cover rides on the male serration portion when the dust cover moves to one axial direction along the non-serration portion. The intermediate shaft according to claim 1, wherein the intermediate shaft is provided at a position where the intermediate shaft is provided. The stopper ring is engaged with a stepped portion facing the other side in the axial direction, which is present in a continuous portion of the non-serrated portion and the male serrated portion of the outer peripheral surface of the target split shaft. The intermediate shaft described. The other side surface in the axial direction of the stopper ring is a part in contact with the dust cover, and the other side surface in the axial direction of the stopper ring is at the same axial position as the other axial end edge of the male serration portion. The intermediate shaft according to any one of claims 2 to 3, wherein the intermediate shaft is disposed. The intermediate shaft according to any one of claims 1 to 4, wherein a tip portion of the screw is a pointed pointed portion. The pointed end portion of the screw is harder than the portion of the outer peripheral surface of the target split shaft that faces the pointed end portion, and the pointed end portion of the outer peripheral surface of the target split shaft faces the pointed end portion. The intermediate shaft according to claim 5, wherein the intermediate shaft is mechanically cut into a portion to be engaged. The intermediate shaft according to any one of claims 1 to 6, wherein a loosening prevention structure for the screw with respect to the screw hole is provided.

Images