JPH0314937A - Shock absorber mounting eye and its manufacturing device and method - Google Patents

Abstract

PURPOSE:To prevent falling-out, slippage of a member inserted into an eye to improve general accuracy by stamping the end face of a bar-shaped solid material to provide a recessed part on the material, stamping again the material and blanking it to obtain a ring-shaped piece with belt-shaped stepped part, and stamping both end parts of the formed piece into a bell-mouth shape. CONSTITUTION:A material of specified size is installed in a die 19, and pressed by a punch 17 and an insert punch 16 to obtain a cylindrical formed piece 10 provided with a recessed part 11. The formed piece is installed in a die 29 and pressed by a punch 29 to obtain a formed piece 20 provided with recessed parts 21, 22. The piece is installed in a die 39 and pressed by a punch 38 to obtain a formed piece 30 provided with recessed pats 31, 32. Further, the formed piece is installed in a die 49 and pressed by a punch 48 to obtain a round-tube shaped half-finished product 40 with a stepped part 41. A punch 58 is then pressed against the half-finished product in a die 59 to obtain a formed piece 50 whose both end parts are formed into a bell-mouth shape. In this way, a highly precise eye can be manufactured efficiently and falling-out and slippage of an inserted member can be prevented by means of the stepped part.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application This invention relates to a shock absorber mounting eye (sway prevention mounting ring) used for the chassis of automobiles and two-wheeled vehicles.

BACKGROUND OF THE INVENTION Conventionally, shock absorber mounting eyes (hereinafter referred to as eyes) have been manufactured using hollow pipe material. Cut the pipe material to the specified length with a cutting tool or metal saw,
The eyes were obtained by chamfering both ends and then expanding the tube by press working.

Problems to be Solved by the Invention Conventional eyes were manufactured by press-expanding a pipe material with a uniform cross section, so the inner surface was flat.

For this reason, the problem of the member inserted into the eye falling out or shifting may occur.

Further, if there is a defect in the pipe material or an error occurs in the cutting process of the pipe material, there is a possibility that the error will remain in the final product obtained by press expansion. As described above, the conventional eye has problems in terms of accuracy.

Purpose of the Invention In view of the problems of the prior art, it is an object of the present invention to provide a shock absorber mounting eye that is highly accurate and capable of preventing the insertion member from coming off or slipping off, as well as its manufacturing device and manufacturing method. .

SUMMARY OF THE INVENTION In order to achieve the above objects, the present invention provides a shock absorber mounting eye according to claim 1, a shock absorber mounting eye manufacturing apparatus according to claim 2, and a shock absorber mounting eye according to claim 3. The gist is the manufacturing method.

Means for Solving the Problems The shock absorber mounting eye of the present invention is made of a generally annular molded product with expanded tubes at both ends. It is characterized by:

Further, the shock absorber mounting eye manufacturing apparatus of the present invention is an apparatus for manufacturing the above-mentioned eye, which comprises: a first punch having a recess in at least one end surface of a rod-shaped solid material; and a bottom of the recess. a second punch for punching out an annular molded product with a band-like step on the inner wall surface, and a third and fourth punch for expanding both ends of the annular molded product into a tubular shape. It is characterized by being a press device equipped with a punch.

It is preferable that the above-mentioned press device includes a fifth punch for forming a recess on the other end face of the hollow product having a recess on one end face. However, the fifth punch may have the same shape as the first punch, or may also serve as the first punch.

The method for manufacturing the shock absorber mounting eye of the present invention includes:
The method for manufacturing the above-mentioned eye includes a pressing process in which a rod-shaped solid material is press-formed and a recess is formed on at least one end surface, and the bottom of the recess is punched out by press-forming to form a band-shaped step. The present invention is characterized in that it includes a pressing step of forming a generally annular molded article having the following: and a pressing step of expanding both ends of the generally annular shaped article into a tubular shape by press molding.

In the above-described manufacturing method, it is desirable that a pressing step of forming a recess on one end surface of the molded product by performing press molding to provide a recess on the other end surface is also desirable.

Note that in this specification, punching also includes counter punching and knockout.

Function: Since the shock absorber mounting eye (hereinafter abbreviated as eye) of the present invention has a band-like stepped portion on the inner wall surface, it is possible to prevent the insertion member from slipping or coming off.

According to the eye manufacturing apparatus according to the present invention, since the eye is manufactured by continuous press molding, the eye can be manufactured efficiently and with excellent precision.

Similarly, according to the method for manufacturing an eye according to the present invention, the eye is manufactured by a series of press moldings, so that the eye can be manufactured efficiently and with high precision.

Example Embodiments of the present invention will be described below with reference to the drawings.

The press forming described below can be performed using a normal press machine. Here, explanation will be given with emphasis on punches, gougs, etc., and explanation on the configuration of the press machine will be omitted.

Note that the press forming described below is preferably performed cold. (
Cold Forging) First, in the first step, a solid rod (coil material) is cut into a predetermined length. For cutting, use a cutting machine such as a cutting tool or a metal saw.

The second step will be explained with reference to FIG. 2a. The material of a predetermined size obtained in the first step is placed in the die 19, and the punch 17 and insert punch 16 are pressed against it. die 19
A knockout 18 is arranged in the through hole in the center.

A small convex portion is provided at the tip of the insert punch l6. The end face of the knockout 18 is flat. Further, a spring (not shown) is provided at the rear of the insert punch 16.

By this press molding, a molded product 10 having a generally cylindrical shape as shown in FIG. 2b is obtained.

A small recess (location) 1l corresponding to the projection of the insert punch 16 is formed on one end surface of the molded product 10.

Next, the third step will be explained with reference to FIG. 3a. The molded product 10 obtained in the second step is placed in the die 29, and the punch 2
Push 8. A knockout hole 8° is arranged in the through hole in the center of the die 29. The tip of the punch 28 is 8 type 2
It is now 8a. The tip of the knockout has a small convex shape.

Step: By press molding in the third step, a molded product 20 shown in FIG. 3b is obtained. A recess 21 corresponding to the protrusion 28a at the tip of the punch 28 is formed on one end surface of the molded product 20. A small recess 22 corresponding to the protrusion at the tip of the knockout 18° is formed on the other end surface of the molded product 20.

The fourth step will be explained with reference to FIG. 4a. The molded product 20 obtained in the third step is placed in a die 39, and a punch 38 is pressed against it. A sleeve 37 is inserted into the through hole in the center of the die 39.
and a counter punch 36 are arranged. sleeve 3
A holder 35 is provided at the rear of 7. The holder 35 has a through hole into which the pin 34 is inserted. pin 3
Press the sleeve in step 4 to remove the molded product. The end face of the punch 38 is provided with a protrusion 38a that is slightly taller than the protrusion 28a of the punch 28. A tall protrusion 36a is provided at the tip of the counter punch 36.

By the press molding in the fourth step, a molded product 30 shown in FIG. 4b is obtained. A deep recess 32 corresponding to the protrusion of the counter punch 36 is formed on one end surface of the molded product 30 . A concave portion 31 corresponding to the convex portion of the punch 38 is formed on the other end face. As a result, the molded product 30 has a concave hole 31
and 32 bottoms or intermediate walls 33 are formed.

The fifth step will be explained with reference to FIG. 5a. The molded product 30 obtained in the fourth step is placed in a die 49, and a punch 48 is pressed against it. A sleeve 47 is inserted into the through hole in the center of the die 49.
and a counter punch 46 are arranged. sleeve 4
A holder 45 is provided at the rear of 7. A bottle 44 is inserted into the through hole of the holder 45. The molded product is taken out by pushing the sleeve 47 with the pin 44. A tall protrusion 46a is provided at the end of the counter punch 46. The diameter of the convex portion 46a of the counter punch 46 is slightly smaller than the inner diameter of the concave portion 32 of the molded product 30 (the fourth
(See Figure 6). The punch 48 is generally cylindrical and has a through hole in the center. Note that in FIG. 5a, the band-shaped stepped portion is omitted for simplicity.

In the press forming step of the fifth step, the intermediate wall 33 of the molded product 30 is punched out to obtain a semi-finished product 40 in the shape of a circular tube as shown in FIG. 5b. A band-shaped step portion 41 is formed in the punched portion of the intermediate wall 33. The size of the step is 0.002mm
Set to ~0.5non. Moreover, the band-like stepped portion 4l can also be provided at other positions that are advantageous when the eye is used.

The sixth step will be explained with reference to FIG. 6a. The molded product 40 obtained in the fifth step is placed in a die 59, and a punch 58 is pressed against it. A sleeve 57 is inserted into the through hole in the center of the die 59.
and a counter punch 56 are arranged. A holder 55 is provided at the rear of the sleeve. A pin 54 is inserted into the through hole of the holder 55.

A spring 53 is arranged on the outside of the sleeve. A sleeve is arranged on the outside of the punch 58, and a case is arranged behind it. A convex portion 58a is provided at the tip of the punch 58. The side surface of this convex portion is curved as shown in FIG. 6a. Further, the tip of the counter punch 56 is also provided with a convex portion 56a having a curved side surface. In FIG. 6a, the band-shaped stepped portion is omitted.

The sixth pipe is expanded at both ends by press forming in the sixth step.
A molded article 50 shown in Figure b is obtained. The molded product 50 has a tubular shape as a whole, and both ends thereof are expanded to form a smoothly curved surface. The band-shaped stepped portion 4 {is also curved and remains as a band-shaped stepped portion 51. FIG. 1 shows an enlarged sectional view of the molded product 50.

The molded product 50 obtained in the sixth step is subjected to deburring, for example, shot blasting, and then subjected to a final inspection to obtain a completed product.

Next, an example of the eye dimensions will be given.

A. 36.9±0.6mm B...32.3mm C-2 5,9±0.3mm D...30±0.5mm (2 points from Tobaro) E...0.2mm Below (height of step part) F-4.5 mm G...6.4 mm H 2 4±0.15 mm Note that the present invention is not limited to the above-mentioned embodiments and can be modified in various ways. For example, the step of providing the recess 2l may be omitted, and the recesses 31 and 32 may be provided simultaneously on the rod-shaped material.

Furthermore, by forming a deep recess on only one surface and punching out the bottom of the recess, the band-like section can be provided closer to the end of the eye.

Effects Normally, when the inner diameter of a tubular molded product is 20 to 30 mm, the tolerance that can be maintained in mass production is generally at a limit of ±0.05. As a result, the larger the tolerance, the easier the management and the lower the cost. In addition, the following points are factors that affect accuracy.

■ Accuracy of material diameter (including variation and surface treatment) ■ Abrasion resistance of mold ■ Rigidity of mold ■ Overall length variation during cutting ■ Machine accuracy ■ Properties and amount of processing oil This is advantageous in the above points and allows the production of highly accurate eyes.

Note that Table 1 shows an example of measuring the dimensions (mm) around the stepped portion. This is F in Figure 1 for 10 formed parts.
SG, the height of the stepped portion was measured.

[Brief explanation of the drawing]

Fig. 1 is an enlarged sectional view showing an embodiment of the shock absorber mounting eye according to the present invention, Figs. 2a to 6a are sectional views showing the manufacturing process, and Figs. 2b to 6b are sectional views to Figs. 2a to 6a, respectively. It is a sectional view showing a molded article in the illustrated manufacturing process. Fig. 2a Fig. 6a

Claims (1)

[Scope of Claims] 1. A shock absorber mounting eye to be attached to an automobile chassis, which is made of a generally annular molded product with both ends expanded to form a tube, characterized by a band-like stepped portion being provided on the inner wall surface of the molded product. Shock absorber mounting eye. 2. An apparatus for manufacturing a shock absorber mounting eye according to claim 1, comprising: a first punch for forming a recess in at least one end surface of a rod-shaped solid material; and a first punch for punching out the bottom of the recess. A second punch for forming an entirely annular molded product with a band-shaped step on the inner wall surface, and third and fourth punches for expanding both ends of the annular molded product into a tubular shape. A press device characterized by: 3. A method for manufacturing a shock absorber mounting eye according to claim 1, comprising: pressing at least one end face of a rod-shaped solid material to form a recess; and pressing the bottom of the recess again. A method comprising a pressing step of forming a generally annular molded product with a band-shaped step by punching the molded product, and a pressing step of expanding both ends of the generally annular molded product into a tubular shape.