JP4096617B2 - Bolt mounting aid - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a bolt mounting aid.
[0002]
[Prior art]
As a structure in which a bolt is press-fitted into a through hole provided in a flange, for example, there is a bearing device that supports driving wheels of an automobile. The basic configuration of this bearing device will be described with reference to FIGS. 1 and 2 presented in the embodiment.
[0003]
In the figure, 1 is a bearing device, 2 is a hub shaft, 3 is a double-row outward angular ball bearing, 6 is a disc rotor of a disc brake device, and 9 is a wheel of a wheel.
[0004]
Bolts 10 are inserted into the through holes 24 provided at several places on the circumference of the flange 21 of the hub shaft 2 in a state where the bolts 10 protrude and are hooked in the axial direction and the circumferential direction.
[0005]
The bolt 10 has serrations 13 formed only in the region on the head side in the shaft portion. The bolt 10 is press-fitted into the through hole 24 by pressurizing the head 11. By this press-fitting, the serration 13 of the bolt 10 bites into the circular inner peripheral surface of the through hole 24, and the bolt 10 is prevented from coming off from the through hole 24 and is prevented from rotating.
[0006]
The nut 15 is screwed into the bolt 10 so that the disc rotor 6 and the wheel 9 are sandwiched and fixed between the outer surface of the flange 21 on the vehicle outer side and the nut 15.
[0007]
[Problems to be solved by the invention]
In the bearing device described above, the mounting angle of the bolt 10 with respect to the flange 21 is defined so that the inclination angle of the central axis P of the bolt 10 with respect to the central axis O of the hub shaft 2 falls within a predetermined allowable range. In order to satisfy such a regulation, conventionally, the bolt 21 is turned with high precision so that the bolt seating surface of the flange 21 is perpendicular to the central axis O of the hub shaft 2.
[0008]
The hub shaft 2 is conventionally shaped by forging and then turned on the mounting surfaces (22, 23) of the double-row outward angular ball bearing 3 and the outer surface of the flange 21 on the hub shaft 2. It is manufactured by. In addition, conventionally, a turning process is further applied to the region that becomes the seating surface of the bolt 10 on the inner surface of the flange 21 on the vehicle inner side. Adding a turning process to the bolt bearing surface causes a cost increase.
[0009]
In order to reduce the cost, the present inventor has been diligently researching so that the turning process for the bolt bearing surface can be omitted.
[0010]
[Means for Solving the Problems]
The bolt mounting assisting tool of the present invention is configured such that a bolt is inserted into a through hole provided in a circumferential direction of the flange of a shaft body having a flange extending radially outward, and is provided at the tip of the shaft portion. A bolt mounting aid used in press-fitting with the side protruding, wherein the bolt shaft portion is provided on the outer periphery of a region to be inserted into the through hole of the flange and bites into the through hole. A serration, a thread groove provided on the outer periphery of the region protruding from the through hole, and an intermediate diameter portion provided between the serration and the screw groove and projecting from the through hole. It has a support part that supports one side of the downstream side in the press-fitting direction with a surface, and in the support part, in the region corresponding to the through-hole of the flange, A guide portion is provided that guides the shaft portion of the bolt protruding in various ways and keeps the inclination of the center axis of the bolt with respect to the center axis of the shaft body within a predetermined allowable range, and the guide portion is the support portion. In the region corresponding to the through hole of the flange in parallel with the central axis of the shaft body , the fitting gap between the circular hole and the shaft portion of the bolt is the center of the shaft body By controlling to a dimension that limits the inclination of the central axis of the bolt with respect to the shaft, the inner diameter of the circular hole is formed slightly larger than the diameter of the tip circle of the thread groove of the bolt , and the circular hole opening side is formed larger than the inner diameter so as not to interfere with the outer diameter of the inner diameter and an intermediate diameter portion of the circular hole for the intermediate diameter portion of the bolt.
[0011]
The shaft body is, for example, a hub shaft provided in a bearing device that supports wheels.
[0012]
In this case, the support portion receives an axial load when the bolt is press-fitted. The guide portion provided in the support portion guides the press-fitting operation of the bolt into the through hole of the flange while properly maintaining the posture of the bolt. That is, since the posture of the bolt can be determined by the accuracy of the guide portion, the flatness of the region that becomes the seat surface of the bolt in the flange can be ignored. Therefore, it is not necessary to turn the region of the flange that becomes the bearing surface of the bolt as in the conventional example.
[0018]
DETAILED DESCRIPTION OF THE INVENTION
In this embodiment, a bearing device 1 that supports driving wheels of an automobile as shown in FIG. 1 and FIG. Here, prior to the description of the bolt mounting aid of the present invention, the configuration of the bearing device 1 will be described.
[0019]
The bearing device 1 shown in the figure has a hollow hub shaft 2 and a double-row outward angular ball bearing 3. The hub shaft 2 corresponds to the shaft body described in the claims.
[0020]
That is, a flange 21 extending radially outward is provided near one end of the hub shaft 2, and the double-row outward angular contact ball bearing is located in a region on the inner side of the vehicle with respect to the flange 21 in the hub shaft 2. 3 is packaged.
[0021]
The double row outward angular ball bearing 3 includes a single outer ring 31 having two rows of raceway grooves, a single inner ring 32 having a single row of raceways fitted to the small-diameter outer peripheral surface 22 of the hub shaft 2, and two A plurality of balls 33 arranged in a row and two crown-shaped cages 34 and 35 are provided, and the large-diameter outer peripheral surface 23 of the hub shaft 2 is configured as one inner ring. A flange 36 extending outward in the radial direction is provided on the outer periphery of the outer ring 31.
[0022]
Through-holes 24 are provided at several places on the circumference of the flange 21 of the hub shaft 2, and the bolts 10 are inserted into the through-holes 24 in a state of being caught in the axial direction and the circumferential direction. Has been. The bolt 10 has, for example, a cylindrical head portion 11 and a shaft portion 12. In the shaft portion 12, serrations 13 are provided on the outer periphery of the region near the head 11, and screw grooves 14 are provided on the outer periphery of the region near the tip. The tooth tip circle diameter of the serration 13 is set larger than the tooth tip circle diameter of the thread groove 14.
[0023]
Then, the flange 36 of the outer ring 31 of the double row outward angular ball bearing 3 is attached non-rotatingly with the bolt 8 to the carrier 7 which is a part of the vehicle body, and the drive shaft 4 is provided on the inner periphery of the hub shaft 2. Are spline-fitted and joined together by the nut 5. Further, the disc rotor 6 of the disc brake device and the wheel 9 of the wheel are sandwiched between the outer surface of the flange 21 of the hub shaft 2 (surface on the vehicle outer side) and the nut 15 screwed to the bolt 10. It is fixed.
[0024]
Next, an embodiment of the bolt mounting aid according to the present invention will be described with reference to FIGS.
[0025]
The bolt mounting auxiliary tool 40 in the illustrated example assists in mounting the bolt 10 in an appropriate posture with respect to the through hole 24 of the flange 21 of the hub shaft 2 in the bearing device 1 described above. In general, in the field of the bearing device 1, a tilt allowable range is defined such that the tilt of the central axis of the bolt 10 with respect to the central axis of the hub shaft 2 is, for example, 1 degree or less. What is within this allowable tilt range is called a proper posture.
[0026]
Specifically, the bolt attachment assisting tool 40 has a support portion 41 that receives the surface on the downstream side in the press-fitting direction of the bolt 10 in the flange 21 of the hub shaft 2, that is, the outer surface on the vehicle outer side.
[0027]
In the center of the support portion 41, a depressed portion 42 into which the vehicle outer side cylindrical portion 25 of the hub axle 2 is inserted in a non-contact state is provided.
[0028]
Further, in the region corresponding to the through hole 24 of the flange 21 in the support portion 41, the shaft portion 12 of the bolt 10 that gradually protrudes from the through hole 24 with the start of press-fitting of the bolt 10 into the through hole 24 is guided, A circular hole 43 is provided as a guide portion for keeping the inclination of the central axis P of the bolt 10 with respect to the central axis O of the hub axle 2 within the allowable inclination range.
[0029]
The circular hole 43 is provided in parallel to the central axis O of the hub shaft 2. The opening side of the circular hole 43 is formed to have a large diameter so as not to interfere with an intermediate diameter portion between the serration 13 and the thread groove 14 in the shaft portion 12 of the bolt 10. The inner diameter R of the portion excluding the opening portion of the circular hole 43 is formed to be slightly larger than the tip circle diameter r of the thread groove 14 in the shaft portion 12 of the bolt 10. More specifically, the fitting gap between the circular hole 43 and the tooth tip of the screw groove 14 of the bolt 10 has a dimension that allows the inclination of the central axis P of the bolt 10 with respect to the central axis O of the hub shaft 2 to fall within the allowable tilt range. It is managed. As this fitting clearance, it can set to 0.05-0.1 mm, for example.
[0030]
The procedure for attaching the bolt 10 using such a bolt attachment auxiliary tool 40 will be described with reference to FIGS.
[0031]
First, the bearing device 1 is set in the vertical orientation, and the outer surface of the flange 21 of the hub shaft 2 is directed downward. The outer surface of the flange 21 of the bearing device 1 is mounted on the upper surface of the support portion 41 of the bolt mounting aid 40. At this time, as shown in FIG. 3, the vehicle outer side cylindrical portion 25 of the hub axle 2 is inserted into the recessed portion 42 in the center of the support portion 41 in a non-contact state, and the circular hole 43 of the support portion 41 is inserted. On the other hand, any one of the plurality of through holes 24 provided in the flange 21 is aligned coaxially.
[0032]
In this state, the shaft portion 12 of the bolt 10 is inserted into the through hole 24 of the flange 21. At this time, as shown in FIG. 4, the bolt 10 is inserted to a position where the tip side of the serration 13 abuts against the vehicle inner side opening of the through hole 24. Along with this, the tip end side of the shaft portion 12 of the bolt 10 protrudes from the through hole 24 and is inserted into the circular hole 43 of the bolt mounting aid 40.
[0033]
Next, the head 11 of the bolt 10 is pressurized in the direction of the downward arrow in FIG. 4 with a pressure device (such as a hydraulic cylinder) (not shown), so that the serration 13 of the bolt 10 is passed through the hole as shown in FIG. 24 is press-fitted. In this press-fitting process, the shaft portion 12 of the bolt 10 is guided by the inner peripheral surface of the circular hole 43 and is guided so that the center axis P of the bolt 10 is substantially parallel to the center axis O of the hub shaft 2. . Therefore, even if the region that becomes the seating surface of the bolt 10 is not smooth on the inner surface of the flange 21, the bolt 10 is press-fitted into the through hole 24 in an appropriate posture regardless of the region.
[0034]
In such a procedure, the remaining through holes 24 provided in the flange 21 of the hub shaft 2 are sequentially performed.
[0035]
If the bolt 10 is attached using such a bolt attachment auxiliary tool 40, it is not necessary to process the seating surface of the bolt 10 smoothly on the inner surface of the flange 21. Accordingly, the hub shaft 2 is manufactured by forging and then turning the mounting surface (22, 23) of the double row outward angular ball bearing 3 and the outer surface of the flange 21 on the hub shaft 2. As in the conventional example, it is not necessary to perform a turning process on a region that becomes the seating surface of the bolt 10 on the inner surface of the flange 21 on the vehicle inner side. Thus, in this embodiment, since the turning process with respect to the bolt bearing surface can be omitted, the cost can be reduced accordingly.
[0036]
In addition, this invention is not limited only to the said embodiment, Various application and deformation | transformation can be considered.
[0037]
(1) FIGS. 6-8 has shown the bolt attachment auxiliary tool 40 which concerns on other embodiment. The bolt mounting assisting tool 40 in this embodiment is different from that in the above embodiment in the guiding portion equipped therein. That is, a circular hole 45 having a larger diameter than the through hole 24 and parallel to the central axis O of the hub shaft 2 is formed in a region corresponding to the through hole 24 of the flange 21 in the support portion 41 of the bolt mounting aid 40. Is provided. In the circular hole 45, a slider 46 is housed so as to be reciprocally movable in the axial direction along the inner peripheral surface thereof, and a coil spring 47 for constantly resiliently biasing the slider 46 upward is housed. ing. Reference numeral 48 denotes a lid for closing the circular hole 45. The slider 46 is provided with a circular recess 49 into which the shaft portion 12 of the bolt 10 is inserted. An inner diameter R <b> 2 of the circular recess 49 is formed to be larger than a tooth tip circular diameter r of the screw groove 14 in the shaft portion 12 of the bolt 10, and the circular hole 43 and the tooth tip of the screw groove 14 of the bolt 10 are formed. The fitting gap is managed to a dimension that allows the inclination angle θ of the central axis P of the bolt 10 with respect to the central axis O of the hub shaft 2 to fall within the allowable inclination range described in the above embodiment. This fitting gap can be set to 0.05 to 0.1 mm, for example, as in the above embodiment.
[0038]
In this case, the reciprocating motion of the slider 46 is guided by the inner peripheral surface of the circular hole 45 of the support portion 41, and the shaft portion 12 of the bolt 10 is slid against the inner peripheral surface of the circular concave portion 45 of the slider 46. Since it is made not to move, especially the thread groove 14 of the axial part 12 of the volt | bolt 10 will not be damaged.
[0039]
(2) The bolt mounting assisting tool 40 of the present invention can be used for a bearing device 1 for a driven wheel as shown in FIG. 9, for example.
[0040]
【The invention's effect】
In the present invention, in the process of press-fitting the bolt into the through hole of the flange, the bolt can be guided while maintaining the proper posture in which the central axis of the bolt is substantially parallel to the central axis of the shaft body. . Therefore, the bolt can be press-fitted into the through hole in an appropriate posture regardless of the fact that the region that becomes the seat surface of the bolt in the flange is not smooth. Therefore, if the bolts are attached using the bolt attachment auxiliary tool of the present invention, it is not necessary to smoothly process the area of the flange seating surface in the flange as in the conventional example, and the processing cost is reduced accordingly. become able to.
[Brief description of the drawings]
FIG. 1 is a cross-sectional view showing a bearing device for a drive wheel, which is an object of use of the bolt mounting aid of the present invention. FIG. 2 is a view of the bearing device of FIG. FIG. 4 is a cross-sectional view showing a bolt mounting aid according to an embodiment. FIG. 4 is a diagram showing a procedure for mounting a bolt using the bolt mounting aid of FIG. FIG. 6 is a sectional view showing a bolt mounting aid according to another embodiment of the present invention. FIG. 7 is a diagram showing a procedure for mounting a bolt using the bolt mounting aid of FIG. 8 is a view showing a state in which a bolt is mounted using the bolt mounting aid of FIG. 6. FIG. 9 is a side view showing a bearing device for a driven wheel to which the bolt mounting aid of the present invention can be applied. Explanation】
2 Hub shaft 10 Bolt 11 Bolt head 12 Bolt shaft portion 13 Bolt serration 14 Bolt thread groove 40 Bolt mounting aid 41 Support portion 43 for bolt mounting aid Circular hole of bolt mounting aid

Claims (1)

When a bolt is press-fitted into the through hole provided in the axial direction at several places on the circumference of the flange having a flange extending radially outward, with the tip end of the shaft protruding. Bolt mounting aid used for
A shaft portion of the bolt is provided on the outer periphery of the region inserted into the through hole of the flange and is serrated into the through hole, and a screw groove provided on the outer periphery of the region protruding from the through hole. An intermediate diameter portion provided between the serration and the thread groove and protruding from the through hole,
A support portion that supports one side surface of the flange on the downstream side in the press-fitting direction of the bolt,
A shaft portion of the bolt that gradually protrudes from the through hole as the bolt starts to be inserted into the through hole is guided to a region corresponding to the through hole of the flange in the support portion, and the central axis of the shaft body A guide portion is provided for keeping the inclination of the central axis of the bolt with respect to a predetermined allowable range;
The guide portion is a circular hole provided in a region corresponding to the through-hole of the flange in the support portion in parallel to the central axis of the shaft body ,
The fitting clearance between the circular hole and the shaft portion of the bolt is controlled to a dimension that restricts the inclination of the central axis of the bolt with respect to the central axis of the shaft body . While being formed slightly larger than the tip diameter of the thread groove ,
The bolt mounting aid, wherein the opening side of the circular hole has an inner diameter larger than the inner diameter of the circular hole and the outer diameter of the intermediate diameter part so as not to interfere with the intermediate diameter part of the bolt.

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