JP2729225B2 - Manufacturing method of grooved bolt - Google Patents

Description

The present invention relates to a method for manufacturing a grooved bolt having a function of displaying a rotation angle, and more particularly to a grooved bolt used as a component for adjusting a suspension alignment of an automobile. And a method for producing the same.

<Conventional Technology> As a component for adjusting suspension alignment of a vehicle, a grooved bolt capable of accurately grasping a rotation angle of a bolt is known.

In this grooved bolt, as disclosed in, for example, Japanese Patent Application Laid-Open No. 63-130234, a vertical groove is provided from the middle to the end of the shaft of the bolt on which the male screw is engraved, and ,
An eccentric disk is fixed below the neck of the bolt head.

The rotation angle (position of the vertical groove) of the grooved bolt can be determined by relying on an angular scale radially displayed on the surface of the eccentric disk.

Generally, in this type of grooved bolt, it is important that the formation direction of the vertical groove coincides with the center of the angular scale of the eccentric disk.

<Problems to be Solved by the Invention> There are the following problems in the conventional technology for manufacturing grooved bolts.

<A> It is difficult in terms of manufacturing to manufacture the vertical groove in such a way that the direction of formation of the vertical groove coincides with the center of the angular scale of the eccentric disk.

 Therefore, the incidence of defective bolts is relatively high.

<B> From the viewpoint of cost reduction, there is a demand for a proposal of a manufacturing technique capable of improving production efficiency.

<C> Not only is it difficult to perform cold working with a bolt former, but also a press die is required for each eccentric disk having a different diameter, which makes the eccentric disk production less compatible.

<Object of the present invention> The present invention has been made in order to solve the above-mentioned problems. The purpose of the present invention is to reduce the number of steps and to set the position of the vertical groove and the angle scale of the eccentric disk. An object of the present invention is to provide a grooved bolt that can be easily and accurately adjusted.

<Structure of the present invention> In order to achieve the above object, the present invention provides a bolt portion having a screw on the outer periphery of a shaft portion and having a vertical groove along the axial direction of the shaft portion on which the screw is cut. A method of manufacturing a grooved bolt, comprising: an eccentric disk having an angular scale coinciding with the vertical groove forming direction, which is fixed to a portion below the neck of the head of the bolt portion,
Positioning the eccentric disk in a specific direction, inserting a bolt forming material having no longitudinal grooves or screws into the eccentric disk, pressing the bolt in the axial direction, Engraving a vertical groove on the circumferential surface of the bolt, crimping the eccentric disk under the neck of the bolt head, and fixing the same, and engraving an angular scale corresponding to the vertical groove forming direction on the eccentric disk The above three steps are performed in parallel, and then a thread is engraved on the outer periphery of the shaft portion over a predetermined range to manufacture a grooved bolt.

<Example> Hereinafter, an example of the present invention will be described with reference to the drawings.

<A> Overall structure of grooved bolt FIG. 2 shows the entire grooved bolt 1 as a final product.

The grooved bolt 1 includes a bolt portion 2 and an eccentric disk 3.

<B> Bolt Part The bolt part 2 is composed of a hexagonal head 21 and a shaft part 22.

Small teeth 23 for caulking the eccentric disk 3 are engraved on the outer periphery of the shaft 22 closest to the head 21.

Further, a screw portion 24 is formed from the middle of the shaft portion 22 to the free end, and two vertical grooves 25a, 25b are formed concavely from the middle of the screw portion 24 to the free end.

These two vertical grooves 25a and 25b are formed at symmetrical positions of the axis of the shaft portion 22.

<C> Eccentric disk The eccentric disk 3 has a bolt hole 31 at a position slightly off the center of the disk as shown in FIG.
A single groove 32 is engraved on the periphery farthest from the center of the bolt hole, and a small-diameter through hole is formed on the line connecting the center of the bolt hole 31 and the single groove 32.
33 are open.

Since the single groove 32 and the through hole 33 are position indications for specifying the formation position of the vertical groove 25a, the single groove 32 may be omitted.

The eccentric disk 3 can be easily manufactured by a single punching using a press machine.

An angle scale for displaying the rotation angle of the grooved bolt 1 is finally provided on the upper surface of the eccentric disk 3 as shown in FIG.
34 are radially provided, and the center of the angle scale 34 coincides with the vertical groove 25a.

<D> Method of Use The grooved bolt 1 is used by inserting a disc-shaped stop plate 9 as shown in FIG.

A pair of tongues 92, 92 protrude from the inner periphery of the eccentric hole 91 of the stop plate 9.
And restricts the rotation and direction of the stop plate 9.

These tongue pieces 92a, 92b are formed in accordance with the cross section of the longitudinal grooves 25a, 25b.

 Next, a method of manufacturing the grooved bolt 1 will be described.

<A> Step of Correcting the Supply Position of the Eccentric Disk The group of eccentric disks 3 having no angle scale 34 as shown in FIG. 4 is transferred to the direction correcting device 4 by a known phase means.

The direction correcting device 4 includes a rotating magnet 41 and a sensor such as a photoelectric tube.
42, and the rotation of the rotating magnet 41 is stopped by a signal from the sensor 42.

Then, when the eccentric disk 3 passes directly below the rotating magnet 41, the rotating magnet 41 lifts one surface of the eccentric disk 3 by magnetism and rotates in a specific direction.

With the rotation of the eccentric disk 3, the through hole 33 keeps revolving, and the through hole
When 33 comes directly below the stationary sensor 42, the sensor 42
Detecting 33, a rotation stop signal is issued to the drive unit of the rotating magnet 41, and the direction of the through hole 33 of the eccentric disk 3 is aligned in a specific direction.

<B> Step of setting eccentric disk As shown in FIG. 5, the transfer arm 5 immediately lifts the eccentric disk 3 whose supply direction has been corrected and transfers it to the press lower die 6.

The transfer arm 5 includes a pair of holding parts 51 and a rod-shaped guide tentacle 52.
Consists of

The holding unit 51 may be either a suction by negative pressure or an electromagnet.

The transfer arm 5 has a structure in which the guide tentacle 52 and the attachment portion 51 are linked, and the eccentric disk 3 is not attached and transferred unless the tip of the guide tentacle 52 is inserted into the through hole 33.

The press lower die 6 has a through hole 61 and a receiving hole 62 communicating with an entrance of the through hole 61.

The through hole 61 is located at a position slightly deviated from the center of the housing hole 62, and the eccentric relationship between the two holes 61 and 62 is the same as the eccentric relationship between the eccentric disk 3 and the bolt hole 31.

In the lower half of the inner circumference of the through hole 61, two parallel to the axis of the through hole 61.
There are three strips 63, 64 protruding.

These strip blades 63, 64 are blades for cutting the vertical grooves 25a, 25b of the grooved bolt 1, as shown in FIG. 6, and have different cutting shapes.

The receiving hole 62 has the same shape as the eccentric disk 3, the depth of the recess is equal to the thickness of the eccentric disk 3, and the receiving hole 62 has a projection on the bottom surface of the receiving hole 62.
There are 65 protruding.

The projection 65 penetrates the through hole 33 of the eccentric disk 3 and
Is provided at a position corresponding to the through hole 33 of the eccentric disk 3.

In this embodiment, as shown in FIG. 6, when the press lower die 6 is viewed from the axial direction of the through hole 61, a straight line connecting the projection 65, the center of the receiving hole 62, and the center of the through hole 61, Strip blade 63,
The case where the straight line passing through the center of the strip blades 63 and 64 is formed on the same row so as to overlap with the straight line passing through the center of the 64, but the straight line passing through the center of the It suffices if it coincides with the center of the projection group.

Then, the transfer arm 5 transfers the eccentric disk 3 to just above the accommodation hole 62 of the press lower die 6, and then descends and sets the eccentric disk 3 in the accommodation hole 62.

At this time, since the transfer arm 5 operates so that the through hole 33 coincides with the protrusion 65 of the press lower die 6, the mutual alignment of the protrusion 65 with the through hole 33 and the bolt hole 31 with the through hole 61 is accurately performed. Will be

When the setting of the eccentric disk 3 is completed, the moving arm 5 returns to the original position for the next setting of the eccentric disk 3.

<C> Step of setting bolts Next, the bolt portion 2 where the vertical grooves 25a and 25b are not engraved
Is inserted into the through-hole 61 through the bolt hole 31.

The lower end of the shaft portion 22 abuts on the upper portions of the blades 63 and 64, and the bolt portion 2 does not descend any further.

<D> Step of Pressing Bolt (FIG. 1) After the bolt portion is set on the lower press die 6, the upper press die 7 movably arranged vertically above the lower press die 6 is lowered to lower the bolt portion 2 The head 21 is pressurized.

The upper press die 7 has a concave portion 71 on its lower surface that is large enough to accommodate the head 21 of the bolt portion 2, and a projection for engraving an angle scale 34 is formed on the radial streak around the concave portion 21.

Therefore, if the pressurization is continued in a state where the head 21 of the bolt portion 2 is accommodated in the concave portion 71, the following three processes proceed in parallel.

One of them is that the blades 63 and 64
The other is a step of engraving 25a, 25b, and the other is a step of caulking the eccentric disk 3 into the bolt portion 2 with the small teeth 23 penetrating into the bolt hole 31, and resting the lower surface of the press upper die 7 on the other side. In this step, the angle scale 34 is engraved at an accurate position on the upper surface of the eccentric disk 3 by strongly pressing the upper surface of the eccentric disk 3.

As described above, in the present invention, the center of the angular scale 34 of the eccentric disk 3 and the formation of the vertical groove 25a are always formed without specially aligning the bolt portion 2 with the eccentric disk 3 and the strip blades 63, 64. When the directions match.

<E> Step of Forming Screw The bolt portion 2 after the pressing step is removed from the lower press die 6.

Then, a screw portion 24 is formed in the lower half of the shaft portion 22 of the bolt portion 2 by a known method.

As a means for forming the thread portion 24 on the shaft portion 22, for example, the thread portion 24 is rolled by passing between a pair of round dies or flat dies.

<Effects of the Present Invention> The present invention is as described above, and the following effects can be obtained.

<B> Until now, the vertical groove forming step, the eccentric disk fixing step, and the angle scale engraving step have been individually performed.

In the present invention, the above three steps can be performed simultaneously in one step only by pressing the belt portion, so that the number of steps can be reduced.

<B> The center of the angular scale of the eccentric disk and the direction of formation of the vertical groove can always be made to coincide exactly without the need to specially align the bolt portion with the eccentric disk or the strip blade.

Therefore, the occurrence rate of defective bolts can be extremely low.

<C> During the transfer of the eccentric disk, the eccentric disk can be supplied to the press lower die in a specific direction.

In addition, since the positioning projection is provided in the receiving hole of the lower press die, the eccentric disk can be accurately positioned.

<D> Conventionally, after an eccentric disk is provided with an angle scale, the eccentric disk is fixed to a bolt, so that the front and back of the eccentric disk must be managed.

According to the present invention, since the angle graduation is given simultaneously with the fixing of the eccentric disk and the bolt, it is not necessary to manage the front and back of the eccentric disk as in the related art.

Therefore, automation of manufacturing the grooved bolt is easy.

[Brief description of the drawings]

FIG. 1 is an explanatory view of a method of manufacturing a grooved bolt according to the present invention, and is a longitudinal sectional view of a press machine at the time of a step of pressing a bolt portion. FIG. Perspective view Fig. 3: Overall perspective view of the eccentric disk before the angle graduation is applied Fig. 4: Illustration of the process of correcting the direction of the eccentric disk Fig. 5: Setting the eccentric disk in the lower press die Explanatory drawing of process FIG. 6: Cross-sectional view of VI-VI in FIG.

Claims (1)

(57) [Claims] 1. A bolt portion having a screw on the outer periphery of a shaft portion and having a vertical groove along an axial direction of the shaft portion on which the screw is engraved;
In a method for manufacturing a grooved bolt comprising an eccentric disk fixed to an underside of a head of a head of the bolt portion and having an angular scale coinciding with a formation direction of a vertical groove, the eccentric disk is oriented in a specific direction The eccentric disk is inserted with a bolt forming material without a vertical groove or screw, and the bolt is pressed in the axial direction to form a vertical groove on the peripheral surface of the bolt. The process, the process of caulking and fixing the eccentric disk under the neck of the bolt head, and the process of engraving an angular scale corresponding to the forming direction of the longitudinal groove on the eccentric disk are performed in parallel. A method of manufacturing a grooved bolt, wherein a thread is engraved over a predetermined range on the outer periphery of a shaft portion.