JPH01262038A - Manufacture of anchor bolt - Google Patents

Abstract

PURPOSE:To manufacture an anchor bolt in short time and with high yield by forging an annular part by constraining the lower half part after forming the lower half part consisting of a spherical head part, shaft part and thread forming part by forging a bar-like material. CONSTITUTION:A circular columnar bar-like material 1 is formed by cutting so as to become slightly larger than the volume of a precompleted anchor bolt 16. The spherical head forming material 8 having the lower half part 18 consisting of a small diameter shaft part 4 and thread forming part 5 at the one end part and the spherical head part 9 in about a spherical shape connected to said shaft part 4 at the other end part is formed via the forging stage continuing this bar-like material 1. This spherical head forming material 8 is constrained by said lower half part 18 and the upper half part having an annular part and punching part is formed by forging the spherical head part 9. The preform material thus obtd. is worked by a punching press to remove a burr and to punch a punching part. The anchor bolt 16 consisting of an annular part 11, a neck groove part 13, flange part 14, shaft part 4 and thread forming part 5 is thus obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a method for manufacturing anchor bolts used in automobile suspension systems and the like.

BACKGROUND OF THE INVENTION A conventional method for manufacturing anchor bolts is shown in Fig. 10 (
A head forming material 106 (FIG. 1(b)) having a head 107 whose diameter is enlarged by upsetting the shaft end of a cylindrical rod material 101 as shown in a) is formed, and the head is continuously formed. 107 is upset-molded to form a spherical head forming material 108 (FIG. 4(c)) having a substantially spherical spherical head 109.

Next, as shown in FIG. 11, the spherical head forming material 108 is hot press formed to form a ring portion 111, a handling portion 112,
A preformed material 110 having a neck groove portion 113, a flange portion 114, a shaft portion 104, and a threaded portion 105 and having burrs 115 on the outer surface is molded. To explain the molding process of this preforming material 110, the spherical head molding material 108 is set in the molding lower mold 160 of a die set as shown in FIG. 14, and then the upper molding upper mold 159 is lowered. A preformed material 110 is molded as shown in FIG.

Subsequently, the burr 11 of the preformed material 110 is removed using a punching press.
5 is removed and the punched portions 112 are continuously punched out to form an intermediate forming material 158 as shown in FIG.
Anchor bolts 116 with predetermined finished dimensions are manufactured.

Problems to be Solved by the Invention In the conventional manufacturing method as described above, the intermediate forming material 1
58 into the anchor bolt 116 of a predetermined size by cutting, manufacturing takes time and reduces productivity.

Furthermore, a large amount of chips and debris are generated, resulting in a large amount of material loss.
There is a problem in that the cost is high.

Another way to solve the problem is to form a cylindrical rod-shaped material in advance, and through a continuous forging process, form a substantially spherical ball head and an axis that is continuous with the ball head and has the same shape as a predetermined finished shape. The upper half has a ring-shaped ring part having a ring shape equal to a predetermined finished shape by forming a lower half part having a threaded part and a threaded part, then restraining the lower half part, and forging the ball head part. to form.

A rod-shaped material can be formed into an anchor bolt with a predetermined finished shape using only functional forging.

Example Embodiments of the present invention will be described below based on the drawings.

Figures 1 to 3 represent the Ha process of anchor bolts,
1(a) shows the rod-shaped material 1, FIG. 1(b) shows the detail forming material 2, FIG. 1(C) shows the shaft forming material 3, FIG. 1(d) shows the head forming material 6, and FIG. ) is a ball head molded material 8, FIG. 2 is a preformed material 10, and FIG. 3 is an anchor bolt 16.

The rod-shaped material 1 is a cylindrical wire rod, and the completed anchor bolt 16
It is cut and formed so that the volume is slightly larger than υ.

First, as shown in FIG. 1(b), a detail forming material 2 is formed by forging a detail 55 having a smaller diameter than the shaft diameter at the end of a rod-shaped material 1.

Subsequently, the end portion of the detail 55 side of the detail molding material 2 is formed into a shaft portion molding material 3 by forging into a shaft portion 4 having a smaller diameter than the shaft diameter and a screw molding portion 5.

Next, a head 7 having a diameter υ larger than the shaft diameter is formed on the opposite end of the threaded part 5 of the shaft forming material 3, and a tapered part 19 is formed approximately at the center of the shaft 4 in the axial direction. Form material 6.

Further, a shaft portion 4 and a screw molded portion 5 having a predetermined finished shape, and a head portion 7 that is continuous with the shaft portion 4 and a substantially spherical spherical head portion 9 are formed by pressure forming to form a spherical head molding material 8. The process of molding the ball head molding material 8 from the head molding material 6 will be explained in detail based on FIG. 4.

The figure shows a die set installed in a forging machine (not shown), with the left half showing the state before forging, and the right half showing the state after forging.

Reference numeral 22 denotes a punch, which moves up and down while being guided by a forming punch guide 21 having a preliminary upper mold part 28 at its lower part.

Also, 23 is a die with a knockout hole 2 passing through the lower part.
6 and holds a mold 24 inside.

The mold 24 is equipped with a preliminary lower mold part 27 that receives the head molding material 6, and a knockout pin 25 is installed in a knockout hole 26 provided in the die 23 below the preliminary lower mold part 27. Rise.

When molding using a die set with the above structure, first,
As shown in the left half of FIG. 4, the preliminary lower mold part 27 of the mold 24
Insert the head molding material 6 into.

Subsequently, as shown in FIG. 4, the punch 22 and forming punch guide 21 are lowered, and by forging, a shaft portion 4, a threaded portion 5, and a substantially spherical ball head 9 having a predetermined finished shape are formed. The spherical head molding material 8 is formed by heading molding.

After that, the punch 22 and the forming punch id 21 rises,
Furthermore, 7 knockout bins 25 are molded and the ball head molding material 8
Push up and remove it from the spare lower mold part 27.

The spherical head forming material 8 formed as described above is further forged and formed into a ring part 11 and a punched part 12 as shown in FIG.
, a preformed material 10 having a neck groove part 13, a flange part 14, a shaft part 4, and a threaded part 5, and in which a burr 15 is generated on the circumference of a ring part 11 is molded. The process of molding the eight-blade preformed material 10 from the spherical head molding material will be described in detail with reference to FIGS. 5 and 6.

5 and 6 show the die stent attached to a blacksmith (not shown). FIG. 5 shows the state before forming, and FIG. 6 shows the state after forming.

First, the lower die 52 will be described. A lower guide 37 is provided with a side knockout hole 48 that penetrates perpendicularly to the lower guide 37, and a side knockout pin 43 is attached to the knockout hole 48. A lower base 36 is still held at the inner lower part of the lower guide 37, and a lower molding die 38 is provided in contact with the upper surface of the lower base 36.

The lower molding die 38 has a knockout hole 42 and a pilot hole 49 penetrating in the vertical direction, a knockout pin 41 is attached to the knockout hole 42, and a spring holder 39 holding a spring 54 and a spring holder 39 holding a spring 54 are installed in the pilot hole 49. A holding mold 44 is mounted, which is pressed upward by a spring 54 and has a carved part 45 for holding the shaft part 4 and the threaded part 4 of the spherical head molding material 8.

The ring portion 11, the punched portion 12, and the neck groove portion 1 of the preformed material 10 are still in the upper opening 51 of the knockout hole 42.
3. A preliminary lower mold part 40 for molding the flange part 14 is provided.

Next, the upper die 53 will be explained. 30 is the upper guide,
Furthermore, an upper base 29 is held at the upper inner side of the guide 30, and an upper molding die 31 is provided in contact with the lower surface of the upper base 29.

The upper molding die 31 is provided with an upper hole 50 penetrating in the vertical direction, and a spring holder 34 holding a spring 32 is attached to the upper hole 50.

Further, the upper molding die 31 is provided with a preliminary upper mold part 35 facing the preliminary lower mold part 40 .

When molding is performed using a die set having the above structure, first, as shown in FIG. 5, the spherical head molding material 8 is inserted into the die engraving part 45 of the holding mold 44. Subsequently, the upper die 53 is lowered.

Here, after the holding mold 44 comes into contact with the spring holder 34, it descends while being equally suppressed from above and below by the springs 32, 54, so that the spherical head molding material 8 is not deformed. Then, as shown in FIG. 6, a preformed material 10 is formed.

Thereafter, the go die 52 rises, and further pushes up the preformed material 1o on which the knockout bottle 41 has been formed, and removes it from the preliminary lower mold part 40. The separated preformed material 10 is returned to the position before molding together with the spring 32 and the holding mold 44, and finally is pressed against the side knockout bin 43 and removed from the holding mold 44.

From the preformed material 1o formed as described above, the burrs 15 are removed using a punching press, and the punched portions 12 are continuously
is punched out to produce an anchor bolt 16 as shown in FIG.

In the above embodiment, the ring part 1 is
A burr 15 occurred on the 1st part of 1 and was removed in the later process, but
As shown in FIG. 7, the ball head forming material 80 and the ball head 9 are formed into a shape that fits between the preliminary upper mold part 62 and the preliminary lower mold part 63 during heading forming, and closed forging molding is performed as shown in FIG. De Bali 1
5 may be prevented from occurring.

Effects As described above, according to the present invention, a bar-shaped material is formed into an anchor bolt with a predetermined finished shape only by forging, so cutting is not required and manufacturing time is shortened, resulting in improved productivity. It is possible to improve the Furthermore, since there are fewer chips and burrs, there is less loss of material and costs can be reduced.

[Brief explanation of the drawing]

1 to 9 represent embodiments of the present invention, and FIGS. 1 to 3 are step-by-step explanatory diagrams of the manufacturing process of an anchor bolt. FIG. 4 is a cross-sectional plan view of the dicent in the process of molding the spherical head molding material. 5 and 6 are cross-sectional plan views of the die set in the process of forming the preformed material. 7 and 8 are cross-sectional plan views of a die set representing an embodiment of the molding process of the preformed material, and FIG. 9 shows the preformed material formed by this die center. FIGS. 10 to 15 show conventional embodiments, and FIGS. 10 to 13 are step-by-step diagrams of the manufacturing process of the anchor bolt. 1st
1 and 12 are cross-sectional plan views of the dicent in the process of forming the preformed material. In the above drawings, (a) in Figs. 2, 3, 9, and 11 to 13 is a partial cross-sectional plan view of the material and product, and (b) is a side view of (a). . (Explanation of symbols) 1... Rod-shaped material. 4...Shaft part. 5...Screw forming part. 8... Ball head molding material. 9...Ball head. 11... bend
Engineering Department. 16... Anchor bolt.

Claims (1)

[Claims] A cylindrical rod-shaped material 1 is formed in advance, and the rod-shaped material 1 undergoes a continuous forging process to form a substantially spherical ball head 9 and the ball head 9.
This step is followed by forming a lower half part 18 having a shaft part 4 and a threaded part 5 having a predetermined finished shape, and restraining the lower half part 18 and forming the spherical head part 9 by forging. A method for manufacturing an anchor bolt, comprising the step of molding an upper half portion 17 having a ring-shaped ring portion 11 having a predetermined finished shape.