JPH03216231A - Manufacture of axial parts - Google Patents

Abstract

PURPOSE:To prevent burrs from being generated by providing a through hole in a diametrical direction in an axial part, crossing the hole with a groove in parallel with an axial direction of the surface of an axial part and forming the through hole on the cold-forged groove bottom. CONSTITUTION:In manufacture of an axial part 11 having the through hole 20 provided on the axial part 14 and the groove 19 which extends in parallel from the axial end in the axial direction on the surface of the axial part 14 and crosses the through hole 20, first, the groove 19 is cold-forged then, the through hole 20 is formed on the bottom part 19a of the groove 19. In this way, the burrs generated at the opening part of the through hole 20 are positioned at the groove bottom part 19a and are not generated at the thread part formed on the axial surface, consequently, a nut can be screwed in without removing the burrs.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention provides a diametrical through hole provided in a shaft portion, and a through hole extending parallel to the axial direction from the shaft end on the surface of the shaft portion. The present invention relates to a method for manufacturing a shaft-shaped component having a cross section that intersects with a cross section.

(Prior Art) For example, the connecting portion between a knuckle arm fixed to the wheel side of an automobile and a tie rod or a member on the vehicle body side generally has a shape shown in Fig. 8 (I) called a ball joint. A shaft-like part is used. This ball joint 1 includes a large-diameter spherical head 2, a shaft portion 3 having a smaller diameter than the spherical head 2 and a tapered surface 3a, and a shaft portion 3 having an even smaller diameter than the shaft portion 3 and having a threaded surface. It consists of a small diameter shaft part 4 in which a part 4a (male thread part) is formed, and as shown in the figure,
The spherical head 2 is supported by the vehicle body side member 6 via the coupling member 5, and the end 7a of the knuckle arm 7 is fitted into the tapered surface 3a of the shaft 3.
Further, the end portion 7a is fastened to the shaft portion 3 by a nut 8 screwed onto the threaded portion 4a. This results in
A knuckle arm 7 is connected to the vehicle body side member 6 so as to be swingable about the spherical head 2 of the ball joint 1. Furthermore, Figure 8 (II
), the small-diameter shaft portion 4 may have a through hole 9 formed in its diametrical direction.
In addition, loosening of the nut 8 is prevented by inserting the split bottle 10 so as to abut one side of the nut 8 screwed onto the threaded portion 4a.

Further, as an example of a shaft-shaped component other than the ball joint 1, there is a pin member 1' constituting a transmission chain as shown in FIG. 9(I). This pin member 1' consists of a head 2' and a shaft part 3', and the shaft part 3' is connected to a pair of roller link plates 66' and a bottle link plate 7'.
By inserting it into the connecting portion with 7', these are alternately and continuously connected. As shown in an enlarged view in FIG. 9 (II), the tip of the shaft portion 3' of the bottle member 1' has an insertion hole 9' with a diameter of It is formed in the direction.

(Problem to be solved by the invention) However, as shown in FIG.
When forming the through hole 9 together with the threaded portion 4a in the small diameter shaft portion 4 of A burr was generated in the opening of the through hole 9 opened on the surface of the through hole 9 during screw forming, and this burr became an obstacle, making it difficult to smoothly insert the split pin 10 into the through hole 9. .

Moreover, contrary to the above, a threaded portion 4a is provided on the surface of the small diameter shaft portion 4.
After forming, the through hole 9 is formed by punching or cutting.
If an attempt is made to form the through hole 9, a burr generated at the opening thereof will protrude into the threaded portion 4a, and as a result,
It was not possible to smoothly screw the nut 8 into the threaded portion 4a. In either case, after the through-hole 9 is formed, it is necessary to deburr the opening of the through-hole 9, which increases the number of work steps and reduces the productivity of this type of product. This would lead to an increase in costs.

In addition, as shown in FIG. 9, in the case where a through hole 9' is formed at the tip of the shaft portion 3' of the pin member 1' constituting the transmission chain, through which the split bottle 10' for preventing slippage is inserted. In this case, burrs are formed on the surface of the shaft portion 3', and these burrs become an obstacle to the roller link plate 6.
It was not possible to smoothly insert it into the connecting portion between '6' and pin link plates 7', 7', and even in this case, deburring work was required.

The present invention deals with the above-mentioned situation, and when manufacturing a shaft-like component in which a through-hole for inserting a split bottle or the like to prevent it from falling out, or a threaded part is formed together with the through-hole, It is an object of the present invention to provide a manufacturing method that can manufacture a shaft-shaped component that can be suitably used without performing a deburring operation on the opening of the through-hole after the through-hole is formed. (Means for Solving the Problems) In order to solve the above problems, the present invention is characterized by the following configuration.

That is, in a method for manufacturing a shaft-shaped component having a diametrical through hole provided in the shaft, and a groove on the surface of the shaft extending parallel to the axial direction from the shaft end and intersecting the through hole, first, , the groove is formed by forging, and then the through hole is formed so that the opening is located at the bottom of the well.

(Function) According to the above manufacturing method, first, a groove extending parallel to the axial direction from the shaft end is formed on the surface of the shaft by forging, and then an opening is positioned at the bottom of the groove. Since a through hole is formed, the opening is not located on the surface of the shaft. Therefore, when a threaded portion is formed on the surface of the shaft portion after the through-hole is formed, there is no possibility that a burr will occur in the opening located at the bottom of the groove due to the thread forming. Thereby, it is possible to smoothly insert a split pin or the like into the through hole without deburring the opening. Also, in the case where a hole is formed by heading, and then, contrary to the above, a threaded part is formed on the surface of the shaft part, and then a through hole is formed, the opening of the through hole is located at the bottom of the groove. Since the opening is located at the same position, the crack formed in the opening will not protrude into the threaded portion formed on the surface of the shaft. Thereby, the nut can be smoothly screwed into the threaded portion without deburring the opening. in this way,
In either case, after the through-hole is formed, the split bottle and the nut can be smoothly installed without deburring the opening.

Further, for example, the shaft-like part is used as a pin member for connecting a roller link plate and a bottle link plate forming an oval shape of a transmission chain, and the shaft part is provided with a split bottle for preventing slippage. Even in the case of forming a through hole for passing through the shaft, the opening of the through hole is opened at the bottom of the hole formed in the shaft, and the hole formed in the opening protrudes from the surface of the shaft. There is no. As a result, the pin member can be smoothly inserted into the connecting portion between the roller wonk plate and the pin link plate without having to perform a deburring operation on the opening.

Furthermore, when a threaded portion is formed on the surface of the shaft of the shaft-like component as described above, by pressing the outer circumferential surface of the nut screwed onto the threaded portion in the axial direction. By making the inner circumferential surface of the nut bite into the groove formed in the shaft, it is possible to prevent the nut from wearing out. (Example) Hereinafter, an example of the present invention will be described based on the drawings. FIG. 1 is a front view of a ball joint shown as an example of a shaft-shaped component formed by the manufacturing method according to the present invention.
, a shaft portion 13 having a smaller diameter than the spherical head 12 and having a tapered surface 13a formed thereon, and a small diameter shaft having a smaller diameter than the shaft portion 13 and having a threaded portion 14a (externally threaded portion) formed on the surface thereof. As shown in the figure, the spherical head 12 is supported on a predetermined member 16 side via a coupling member 15, and a tapered surface 13a on the shaft portion 13.
A predetermined member 17 is fitted therein, and the member 17 is fastened to the shaft portion 13 by a nut 18 screwed onto the threaded portion 14a. As a result, for example, for one predetermined member 16, the other predetermined member 17
are connected to each other so as to be swingable around a spherical head 12 of a ball joint 11.

As shown in an enlarged view in FIG. 2.3, the small-diameter shaft portion 14 is formed with a pair of shafts 19.19 extending parallel to the axial direction from the shaft end, and each shaft 19.19. 1
A diametrical through hole 20 is formed such that the opening is located at the bottom portions 19a, 19a of the threaded portion 14a, and a cotter pin is inserted into the through hole 20 so as to abut one side of the nut 18 screwed into the threaded portion 14a. (not shown) is inserted to prevent the nut 18 from loosening.

Note that the formation position of the through hole 20 is at the pole joint l.
- It is appropriately set in accordance with the thickness of the predetermined member l7 fitted to the shaft portion 13 of 11 and the nuts 1 and l8 for fastening the member 17.

Next, an example of the manufacturing process of the ball joint 11 according to the manufacturing method of this embodiment will be explained based on FIG. 4. Note that this ball joint 11 is constructed using a plurality of forging stations each consisting of a pair of punches and a gouger, and a metal round bar cut to a predetermined size is successively forged in stages between each forging station. It is now molded using a well-known heading molding machine. That is, Fig. 4 (I
), at a predetermined forging station (A), an intermediate molded product 11' in which a spherical head 12, a shaft portion 13, and a small diameter shaft portion 14 have been formed at each preceding forging station is punched 21 By driving the tip of the intermediate molded product 11' into the die 23 which is fitted and fixed in the die block 22, the intermediate molded product 11' A pair of grooves 19, 19 are formed in the small diameter shaft portion 14 at. Next, with the ejecting operation of the knockout bottle 24,
The intermediate molded product 11' discharged from the die 23 is transferred to the forging station (B).
), the punch 25 is inserted into the die 26, and in this state, the punching tool 27 provided on the upper surface of the Gui block 22 and the die 26 is lowered by an appropriate driving means, and the intermediate molded product is cut by the tip thereof. Bottom part 19a of each groove l9, 19 formed in small diameter shaft part 14 at 11'
, 19a is formed. At the time of forming the through hole 20, the blank b punched out by the punching tool 27 is discharged to the outside of the machine through the discharge holes 22a and 26a provided below the die 26 and the Gui block 22. . Thereafter, on the outer periphery of the small diameter shaft portion 14,
As shown in FIG. 1, by forming the threaded portion 14a, a ball joint 11 having a predetermined shape is formed.

The threaded portion 14a can be formed continuously with the forging by, for example, arranging a conventionally known oval thread rolling device on the downstream side of the forging station (B). Alternatively, the intermediate molded product 11
' may be taken out of the heading molding machine and then formed by cutting or rolling in a separate process. Also,
In this embodiment, in the forging station (B), the through hole 20 is formed by punching between the grooves 19, 19 of the intermediate JFR molded product 11'. After the product 11' is taken out of the heading molding machine, the through holes 20 may be formed between the blanks 19, 19 by punching or cutting in a separate step.

Note that the knockout pin 24 has grooves 24 corresponding to the protrusions 23a, 23a formed on the inner peripheral surface of the die 23.
a, 24a are formed.

As described above, according to the manufacturing method of this embodiment, first, a pair of grooves 19, 19 extending parallel to the axial direction from the shaft end are formed on the surface of the small diameter shaft portion 14 by forging, and then the grooves 19 , 19 bottom 19a. The through hole 20 is formed such that the opening is located at the opening 19a.
0 is never located on the surface of the small diameter shaft portion 14. Therefore, when forming the threaded portion 14a on the surface of the small diameter shaft portion 14 after forming the through hole 20, each
There is no possibility that burrs will form in the openings located at the bottoms 19a, 19a of the screws due to thread forming.

Thereby, a split bottle or the like can be smoothly inserted into the through hole 20 without deburring the opening. Further, a pair of grooves 19, 19 are formed by forging, and then, contrary to the above, the threaded portion 14 is formed on the surface of the small diameter shaft portion 14.
a and then the through hole 20, the opening of the through hole 20 is located at the bottom 1 of each groove 19, 19.
9a. 19a, there is no possibility that a burr generated in the opening will protrude into the threaded portion 4a formed on the surface of the small diameter shaft portion 14. Thereby, the nut l8 can be smoothly screwed into the threaded portion 14a without removing the burr from the opening. In either case, after the through hole 20 is formed, the split bottle and the nut 1 can be smoothly removed without deburring the opening.
8 can be attached to the small diameter shaft portion 14.

Furthermore, as shown in FIG. 2, by pressing the outer circumferential surface of the nut 18 screwed onto the threaded portion 14a in the axial direction, the inner circumferential surface of the nut 18 is pressed against the small diameter shaft portion 14. By biting into one of the pair of grooves 19, it is possible to prevent the nut 18 from loosening.

Further, as shown in Fig. 5.6, the shaft-shaped parts formed by the manufacturing method of this embodiment are connected to each pair of roller link plates 37, 37 and bottle link plates 38, 38 that constitute the transmission chain. The head 32 and the shaft 33 are integrally formed, and the shaft 33 is fitted with a split bottle (see figure) to prevent it from coming off. through-hole 40 for inserting (not shown)
Even in the case where the opening of the through hole 40 is formed in the shaft part 33, the bottom part 39a,
39a, so that the gap formed in the opening does not protrude from the surface of the shaft portion 33. Thereby, the pin member 31 can be smoothly inserted into the connecting portion between the roller link plate 37 and the bottle link plate 38 without removing the burr from the opening.

Further, as shown in FIG. 7, a pair of grooves 59, 59 are respectively formed at both ends of the shaft of the pin member 51 as a shaft-shaped component by forging, and then a pair of grooves 59, 59 are formed at the bottom 59a of each arm 59, 59.
The a through holes 60 and 60 may be formed such that the opening is located at 59a.

Note that the plurality of grooves 19 and 19 are formed so that the through holes 20 and 40.60 are orthogonally formed, and the openings of the through holes 20 and 40.60 are positioned at the bottom accordingly. ...19.39...39.59...5
9 (Effects of the Invention) As described above, according to the present invention, the through hole is formed such that the opening is located at the bottom of the groove formed on the surface of the shaft by compression. This prevents the opening from being located on the surface of the shaft. As a result, when a threaded portion is formed on the surface of the shaft portion after the through-hole is formed, there is no possibility that a flash will occur in the opening located at the bottom of the groove due to thread forming. Therefore, a split bottle or the like can be smoothly inserted into the through-hole without deburring the opening. Furthermore, even in the case where a groove is formed by forging, and then, contrary to the above, a threaded part is formed on the surface of the shaft part and then a through hole is formed, the burrs generated at the opening of the through hole are Since the burr is located at the bottom of the groove, the burr does not form on the threaded portion formed on the surface of the shaft portion.

Thereby, the nut can be smoothly screwed into the threaded portion without deburring the opening.

In this way, in any case, after the through-hole is formed, the cotter pin and nut can be installed smoothly without having to deburr the opening. It becomes possible to reduce the number of steps, and it is possible to improve the productivity and reduce the cost of this type of shaft-shaped component.

Further, for example, the shaft-shaped component is used as a bin member for connecting a roller link plate and a bin link plate that constitute a transmission chain, and a split bin for preventing slipping is attached to the shaft part. Even when forming a through hole for insertion, according to the manufacturing method of the present invention,
Since the opening of the through-hole is opened at the bottom of the hole formed in the shaft, the gap formed in the opening does not protrude onto the surface of the shaft. As a result, the bottle member can be smoothly inserted into the connecting portion between the roller link plate and the pin link plate without performing a deburring operation on the opening.

Furthermore, as mentioned above, if a threaded portion is formed on the surface of the shaft portion of the shaft-shaped component, the outer circumferential surface of the nut screwed onto the threaded portion may be pressed in the axial direction. By making the inner circumferential surface of the nut bite into the groove formed in the shaft portion, it is possible to prevent the nut from loosening.

[Brief explanation of drawings]

1 to 7 show embodiments of the present invention. FIG. 1 is a front view of a ball joint shown as an example of a shaft-shaped component molded by one manufacturing method in this embodiment, and FIG. 1st
Figure 3 is an enlarged end view taken along the line ■-■ in the figure, Figure 3 is a sectional view taken along the line ■-■ in Figure 2, and Figures 4 (1) and (II) respectively show the forming process of the ball joint according to the manufacturing method of this example. 5 is a front view of a pin member constituting a transmission chain shown as an example of other shaft-shaped parts; FIG. 6 is a schematic process diagram shown in FIG.
The figure is a sectional view taken along the line Vl--Vl in Fig. 5, and Fig. 7 is a front view of another shaft-shaped component. In addition, Fig. 8 (I),
(II) is a front view of a conventional ball joint, an enlarged end view of the main part of the ball joint, and FIGS. 9(1) and (I
f) is a front view of a bottle member constituting a conventional transmission chain and an enlarged end view of a main part of the bottle member. 11 31 51...Shaft-shaped part (11...Ball joint, 31.51...Bin member), 14,3
3.53...shaft part (14...small diameter shaft part), 19,3
9.59... Clear, 19a, 39a, 59a... Bottom, 20, 40.60... Through hole. 1. Lucky Philosophy》 Fig./15 Li, -II1 Fig. 4 (ml Fig. 8 Fig. 9 (I [) Fig. 9 (I) (II) also

Claims (1)

[Claims] (1) A method for manufacturing a shaft-like component having a diametrical through hole provided in the shaft, and a groove on the surface of the shaft extending parallel to the axial direction from the shaft end and intersecting the through hole. A method of manufacturing a shaft-shaped component, characterized in that first, the groove is formed by forging, and then the through hole is formed so that the opening is located at the bottom of the groove.