JPH0761523B2 - Ring bolt manufacturing method - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a wheeled bolt used for a suspension system of an automobile.

Conventional Technology As a conventional method for manufacturing bolts with wheels, see Fig. 10 (a).
A head forming material 106 (FIG. 2B) having a head 107 in which the shaft end portion of a cylindrical rod-shaped material 101 as shown in FIG. A ball-head molding material 108 (FIG. 11C) having a substantially spherical ball head 109 is formed by upsetting.

Next, as shown in FIG. 11, the ball head molding material 108 is hot press molded to form a ring portion 111, a punching portion 112, and a neck groove portion 11.
3. A preforming material 110 having a collar portion 114, a shaft portion 104, and a screw forming portion 105 and having a burr 115 on the outer surface is formed. Explaining the forming process of the preforming material 110, the ball head forming material 108 is set in the forming lower mold 160 of the die set as shown in FIG. 14, and then the forming upper mold 159 is lowered from above,
As shown in FIG. 15, the preforming material 110 is formed.

Next, the burr 115 of the preforming material 110 is removed by a punching press, the intermediate forming material 158 as shown in FIG. As shown in the figure, a ring bolt 116 having a predetermined finish size is manufactured.

Problems to be Solved by the Invention In the conventional manufacturing method as described above, the intermediate molding material 15
Since 8 is formed into a ring bolt 116 having a predetermined size by cutting, it takes time to manufacture and productivity is reduced. Further, there is a problem that a large amount of chips and burrs are generated, resulting in a large material loss and an increase in cost.

Means for Solving Problems A cylindrical rod-shaped material is formed in advance, and a substantially spherical ball head is formed through a forging process in the axial direction in which the rod-shaped material is continuous, and a predetermined finishing shape is continuous with the ball head. Molding a lower half having a shaft portion and a screw forming portion equal to, and then constraining the lower half,
In addition, the ball head is forged in the direction perpendicular to the axis to form the upper half portion having a ring-shaped ring portion having a predetermined finished shape.

Action The rod-shaped material can be formed into a bolt with a ring that has the same finished shape by only forging.

EXAMPLES Examples of the present invention will be described below with reference to the drawings.

1 to 3 show a forging process of a bolt with a ring, FIG. 1 (a) is a rod-shaped material 1, FIG. 1 (b) is a detailed molding material 2, and FIG. 1 (c) is a shaft molding material 3. 1D shows a head forming material 6, FIG. 1E shows a ball head forming material 8, FIG. 2 shows a preforming material 10 and FIG. 3 shows a bolt 16 with a ring.

The rod-shaped material 1 is formed by cutting a cylindrical wire rod so as to have a size slightly larger than the volume of the completed bolt 16 with a ring.

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

Subsequently, the shaft portion forming material 3 is formed by pressing the end portion of the detail forming material 2 on the side of the details 55 into the shaft portion 4 and the screw forming portion 5 each having a diameter smaller than the shaft diameter in the axial direction.

Then, a head 7 having a larger diameter than the shaft diameter is formed at the end of the shaft forming material 3 opposite to the screw forming portion 5, and a taper portion 19 is formed in the axial direction substantially in the center of the shaft portion 4 in the axial direction. The part forming material 6 is formed.

Further, the shaft portion 4 and the screw forming portion 5 having a predetermined finish shape
Then, a ball head forming material 8 is formed by press forming a head 7 continuous with the shaft portion 4 and a ball head 9 having a substantially spherical shape in the axial direction. The process of forming the ball-shaped forming material 8 from the head-forming material 6 will be described in detail with reference to FIG.

The figure shows a die set mounted on a forging machine (not shown), in which the left half shows the state before forging and the right half shows the state after forging.

Reference numeral 22 denotes a punch, which is guided by a forming punch guide 21 provided with a preliminary upper mold portion 28 at a lower portion thereof and ascends and descends.

Also, at 23, a die is used to knock out holes 26 that penetrate the lower part.
And holds the mold 24 inside.

The molding die 24 has a preliminary lower mold portion 27 that receives the head molding material 6.
The knockout pin 25 is attached to the knockout hole 26 provided in the die 23 below the preliminary lower mold part 27, and the knockout pin 25 rises at the time of knockout.

When molding with the die set of the above structure, first,
As shown in the left half of FIG. 4, the head forming material 6 is inserted into the preliminary lower die portion 27 of the forming die 24.

Then, as shown in the right half of FIG. 4, the punch 22 and the forming punch guide 21 are lowered to axially press-form the shaft portion 4, the screw forming portion 5 having a predetermined finished shape, and the substantially spherical spherical head. A ball-head molding material 8 is formed by pressing the part 9 and the molding.

After that, the punch 22 and the forming punch guide 21 are raised, and the ball head forming material 8 on which the knockout pin 25 is formed is further pushed up and removed from the preliminary lower mold part 27.

The spherical head forming material 8 formed as described above is further forged in the direction perpendicular to the axis line, and as shown in FIG. 2, the ring portion 11, the punching portion 12, the neck groove portion 13, the collar portion 14, the shaft portion 4, and the screw. The preforming material 10 having the forming portion 5 and having the burr 15 generated around the ring portion 11 is formed. The process of forming the preforming material 10 from the ball-head forming material 8 will be described in detail with reference to FIGS. 5 and 6.

5 and 6 show a die set mounted on a forging machine (not shown). FIG. 5 shows a state before molding and FIG. 6 shows a state after molding.

First, the lower die 52 will be described. 37 is a lower guide, which is a side knockout hole penetrating perpendicularly to the lower guide 37.
A side knockout pin 43 is attached to the side knockout hole 48. A lower base 36 is held in the lower inside 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 that penetrates vertically.
And a knockout hole 42, the knockout pin 41 is mounted in the knockout hole 42, and the pilot hole 49 is pressed by the spring holder 39 holding the spring 54 and the spring 54 in the upward direction. 8 shaft part 4 and screw forming part 5
A holding die 44 having a die engraving portion 45 for holding the is attached.

Further, the upper opening portion 51 of the knockout hole 42 is provided with a preliminary lower mold portion 40 for molding the ring portion 11, the punching portion 12, the neck groove portion 13, and the collar portion 14 of the preliminary molding material 10.

Next, the upper die 53 will be described. Reference numeral 30 denotes an upper guide, and an upper base 29 is held on an upper portion inside the upper guide 30, and an upper molding die 31 is provided in contact with a lower surface of the upper base 29.

The upper molding die 31 is provided with an upper hole 50 penetrating in the vertical direction,
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.

In the case of molding with the die set having the above structure, first, as shown in FIG. 5, the ball head molding material 8 is inserted into the carved portion 45 of the holding mold 44. Then, the upper die 53 is lowered.

Here, since the holding die 44 comes into contact with the spring holder 34 and is pushed down by the springs 32.54 evenly from above and below, the ball head forming material 8 is not deformed. And the sixth
As shown in the figure, the preforming material 10 is forged in the direction perpendicular to the axis.

After that, the lower die 52 rises, the preform material 10 having the knockout pins 41 formed thereon is pushed up, and is removed from the preliminary lower mold part 40. The detached preforming material 10 is returned to the position before forming together with the holding die 44 by the spring 32, and finally pressed by the side knockout pin 43 to be removed from the holding die 44.

The burr 15 is removed from the preformed material 10 formed as described above by a punching press, and the punched portion 12 is continuously punched to manufacture a bolt with a ring 16 as shown in FIG.

In the above-mentioned embodiment, the burr 15 was generated around the ring portion 11 when the preforming material 10 was formed, and was deleted in a later step. However, as shown in FIG. In the direction forging press forming, the burr 15 may be prevented from being formed by the closed forging as shown in FIG. 8 by forming it into a shape that fits between the preliminary upper mold part 62 and the preliminary lower mold part 63.

As described above, according to the present invention, the lower half part is formed in the axial forging process, and the upper half part having the ring part is formed in the axial vertical forging process. Since the bolt with a wheel having the same shape as the finished shape is formed, the cutting process is unnecessary and the manufacturing time is shortened, so that the productivity can be improved. Further, since the generation of chips and burrs is small, the loss of material is small and the cost can be reduced.

[Brief description of drawings]

1 to 9 show an embodiment of the present invention, and FIGS. 1 to 3 are step-by-step explanatory views of a manufacturing process of a bolt with a ring. FIG. 4 is a cross-sectional plan view of the die set in the axial forging forming step of the ball head forming material. 5 and 6 are cross-sectional plan views of the die set in the forging process in the direction perpendicular to the axis of the preforming material. 7 and 8 are cross-sectional plan views of a die set showing another embodiment of the forming process of the preformed material, and FIG. 9 is the preformed material formed by this die set. FIGS. 10 to 15 show a conventional embodiment, and FIGS. 10 to 13 are step explanatory views of a manufacturing process of a wheel bolt. 11 and 12 are cross-sectional plan views of the die set in the forming process of the preforming material. In the above drawings, FIG. 2, FIG. 3, FIG. 9, FIG. 11 to FIG.
(B) is a side view of (A). (Explanation of symbols) 1 …… Steel material 4 …… Shaft 5 …… Screw forming part 8 …… Spherical head forming material 9 …… Spherical head 11 …… Ring part 16 …… Bolt with ring 17 …… Upper half Part 18 ... Lower half

Claims (1)

[Claims] 1. A cylindrical rod-shaped material 1 is preliminarily formed, and a substantially spherical ball head 9 and a predetermined ball-shaped head 9 are continuously formed through an axial forging step in which the rod-shaped material 1 is continuous. A step of forming a lower half portion 18 having a shaft portion 4 and a screw forming portion 5 having the same finished shape, a step of constraining the lower half portion 18 and forging the ball head 9 in a direction perpendicular to the axis line to a predetermined shape. A method for manufacturing a bolt with a ring, comprising a step of forming an upper half portion 17 having a ring-shaped ring portion 11 having the same finished shape.