JPH06104402B2 - Manufacturing method of automobile tow hook - Google Patents

Description

Detailed Description of the Invention a. OBJECT OF THE INVENTION (Field of Industrial Application) The present invention relates to a method of manufacturing a tow hook for an automobile. For more information,
The present invention relates to a method for mass-producing inexpensive products at a low cost by forming a hook support from a single plate material by press working in three steps and welding hooks to the plate to obtain a product.

(Prior Art) In a conventional automobile tow hook, a vertical piece 12 and an L-shaped piece 13 are separately formed as shown in FIG. 7, and both are spot-welded so that their upper edges are aligned. After that, U on the vertical piece 12 side
The product as shown in FIG. 6 is manufactured by the method of welding the base of the hook 14 of a shape or the like.

(Problems to be Solved by the Invention) When the vertical piece 12 and the L-shaped piece 13 are individually press-formed and are joined by welding as in the above-described conventional manufacturing method, the die allowance for pressing, Not only the processing cost, management cost, and other costs are high, but also the assembly cost is high, and the product cost is high. Also, when connecting separate parts, use an assembly jig to maintain accuracy. However, there is a problem in that variations occur in the products and perfect homogenization cannot be expected.

The present invention has been made to solve the above-mentioned conventional problems. One piece and another piece constituting a hook support body are connected to each other to complete the hook support body by press working in only three steps. It is an object of the present invention to provide a method of manufacturing a tow hook, in which the manufacturing cost of the tow hook can be significantly reduced and the product can be made completely uniform by welding the hook.

B. Configuration of the Invention (Means for Solving the Problems) The means for achieving the above-mentioned object is the first step of punching out a raw material plate material from which one piece and another piece are connected by a joint, and one piece of this material. And a second step of forming a bent edge for reinforcement and a bead on the other piece, and bending the one piece and the other piece from the joint portion to polymerize, and bending the other piece from the middle portion to an L shape to form the hook support. It is a method of manufacturing a tow hook for an automobile having a third step of forming and a fourth step of welding a base of the hook to one side of the hook support.

(Operation) In the method of the present invention described above, first, the pair of raw materials a and a in which the one piece 1 and the other piece 2 are connected by the joint portion 3 are punched out from the raw material plate material as shown in FIG. Next, the side edges of the one piece 1 and the other piece 2 of the materials a and a are bent and bent as shown in FIG. 3 to form the reinforcing edges 8, and the plate surface is provided with a reinforcing edge as shown in FIG. The beads 9 are squeezed out to give the materials a and a sufficient mechanical strength. Next, as shown in FIG. 4, the materials a and a are respectively bent from the joint portion 3 and the intermediate portion of the other piece 2, and a part of the other piece 2 is made into one piece 1 as shown in FIG. Polymerize,
The other part is bent laterally at a substantially right angle so that the other piece 2 is L-shaped and the pair of hook supports b, b are formed. Then, when these hook supports b, b are separated from the middle boundary, a pair of hook supports b, b are completed, so that a U-shape or the like is provided above each piece 1 of the completed pair of hook supports b, b. By welding the base of the hook 11 of so that the tow line can be hung on the upper part,
The tow hook as shown in FIG. 1 can be efficiently manufactured, and the manufactured product does not cause variations.

It should be noted that the above-described operation has been described with respect to the two-cavity method of the product having high processing efficiency, but the invention is not necessarily limited to the two-cavity method, and one-cavity or three-cavity or more may be adopted. Absent.

(Example) Below, the Example of the method regarding this invention is described based on drawing.

In the drawing, a and a are a pair of materials, and two pieces having a shape as shown in FIG. 2 in which one piece 1 and the other piece 2 are connected by a joint 3 are symmetrical so that the other piece 2 is connected at the terminal side. It is formed by the first pressing process of punching two pieces arranged in a regular manner from the raw material plate material. In this process, a hole 4 is formed in the center of the joint 3 and a cut 5 is formed on both sides. , 5 are provided, and in the middle of the side edges of the other pieces 2,2, notches 6,6 are provided with a depth matching the reinforcement edge described later, and on both sides of the part where the two other pieces 2,2 are connected. Is a notch
Put 7 and 7, and insert 1 piece by the hole 4 and notches 5 and 5 mentioned above.
When bending the other piece 2 from the joint part 3, it is easy to bend and the notch 6,
6 makes it easier to bend the other piece 2 from the middle to the L-shape, and the cuts 7, 7 make it possible to accurately cut the two other pieces 2, 2 from the boundary.

Reference numerals 8 and 9 denote reinforcing edges and reinforcing beads respectively provided on the one piece 1 and the other piece 2 of the materials a, a, and the reinforcing edge 8 has side edges of the one piece 1 and the other piece 2 as shown in FIG. Bend back to
The reinforcing bead 9 is formed on the plate surfaces of the one piece 1 and the other piece 2 by the second pressing step of squeezing as shown in FIG.
Since both are made of plate material, the one piece 1 and the other piece 2 which have poor mechanical strength are reinforced so that both are given sufficient mechanical strength. Make sure to punch out the bolt hole 10 for mounting to.

b and b are hook supports formed by the above-mentioned materials a and a,
As shown in FIG. 4, starting to bend the materials a and a as shown in FIG. 4 from the joint portion 3 of the one piece 1 and the other piece 2 and the notches 6 and 6 provided in the middle of the other piece 2. Part of the other piece 2 is polymerized into one piece 1,
The other piece 2 is formed by a third pressing step in which the middle end bends laterally to end the bending so as to form an L-shape. After this step is finished, the pair of hook supports b, b is attached to the other piece. The pair of hook supports b, b is obtained by cutting from the positions of the notches 7, 7 provided at the connecting portions of 2, 2.

Reference numeral 11 denotes a hook, which is formed by bending a steel round bar into a U shape, and the base side thereof is welded to the upper side of one piece 1 of the hook support b as shown in FIG. 1 by the fourth welding process. b
It is to complete the tow hook that is connected to and the tow measure can be applied to the upper part.

C. EFFECTS OF THE INVENTION As described above, according to the method of the present invention, one piece and the other piece of the hook support can be connected to each other and can be formed only by the press working in three steps. Since the management cost and other costs are about half that of the conventional manufacturing method, and no assembly cost is required, the product cost can be significantly reduced.

The hook support is completed by press working under uniform conditions, and there is no cause of variation, so that it is possible to completely homogenize all products.

It has unique effects such as.

[Brief description of drawings]

FIG. 1 is a perspective view of a tow hook manufactured by the method according to the present invention. FIG. 2 is a plan view showing a material obtained by the first step of the method according to the present invention. FIG. 3 is a plan view of the material reinforced by the second step. FIG. 4 and FIG. 5 are front views showing a process of forming and a completed state of the hook support according to the third step. FIG. 6 is a perspective view of a tow hook manufactured by a conventional manufacturing method. FIG. 7 is a perspective view showing the parts before assembly of the same as above. a …… Hook support 1 …… One piece 2 …… Other piece 3 …… Joint part a …… Material b …… Hook support 11 …… Hook

Claims (1)

[Claims] Claim: What is claimed is: 1. A first step of punching a material from a raw material plate material in which one piece and another piece are joined by a joint portion, and a second step of forming a bending edge and a bead for reinforcement on the one piece and the other piece of the material, one piece And a third step of bending the other piece from the joining portion to polymerize it, and bending the other piece from the middle portion into an L shape to form a hook support, and welding the base of the hook to one side of the hook support. A method of manufacturing a tow hook for an automobile, which comprises four steps.