JPS5817691B2 - Method of forming shafts protruding from metal plate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for forming an axle neck consisting of a rotary shaft, support, or the like integrally protruding from substantially the edge of a metal plate.

Conventionally, as a method of providing a shaft on at least one edge of a metal plate such as an arm or a lever, as shown in FIG.
The protrusion opening of the pre-formed shaft A is fitted into the hole 2 of the metal plate C and fixed by caulking, or the shaft A is implanted into the metal plate C by spot welding as shown in Fig. 2. Was.

However, according to those methods, in the former method, the tip of the metal plate C is bent due to the caulking pressure, and the perpendicularity of the axis A to the metal plate C cannot be obtained. Because it was narrow, it lacked strength.

In addition, in the latter method, a gap G is created between the metal plate C and the shaft A, causing variations in shaft height, and the welding area is small, resulting in insufficient strength, and the shaft center may be offset. It had many drawbacks.

Furthermore, both methods require a large number of processes and man-hours, and are inevitably expensive, as the forming of the metal plate and the forming of the shaft are performed separately and then assembled together. It had become.

An object of the present invention is to provide a method for forming a shaft neck protruding from a metal plate, which can eliminate the various drawbacks of the prior art described above.

Hereinafter, one embodiment of the present invention will be described based on the drawings.

The metal plate shown in FIG. 3a is, for example, a lever 1, and both end edges 2 are formed in a substantially U-shape, and tongue pieces 3 are respectively connected from the open ends of this U-shape.

The lever 1 and the tongue piece 3 are stamped and formed by a well-known press process.

Next, the tongue piece 3 is bent to stand up at right angles to the surface of the lever 1, as shown in FIG.

At this time, the height Hl of the raised portion of the tongue piece 3 is set higher than the height H2 of the final formed shaft 4, which will be described later.

Preferably, when the volume of the tongue piece 3 is A and the volume of the shaft 4 is B, the relationship A=B, (1,3 to 1.5), and the maximum external dimension of the tongue piece 3. It is preferable to set the height of the tongue piece 3 so that the height of the tongue piece 3 is smaller than the external dimension of the shaft 4.

The lever 1 molded as described above is placed in a press mold 5 shown in FIG. 4.

The press mold 5 includes an upper mold 6, a lower mold 7, and a compression punch 8, and the compression punch 8 moves in the vertical direction with respect to the upper mold 6.

The upper die 6 is provided with a hole 6 having the same outer shape as the shaft 4, and the compression punch 8 is inserted into the hole 6.

On the other hand, the lower mold 7 is provided with a concave groove 7a for clamping the flat part of the lever 1 in cooperation with the upper mold, and a seat 7b that is continuous with the recessed groove 7a and is positioned corresponding to the hole 6a of the upper mold 6. ing.

The seat portion 1b on the side opposite to the groove 7a has a circular arc portion 7 formed in a substantially circular arc shape extending from the face surface 7c to the bottom portion.
d, and this arcuate portion 7d is positioned corresponding to the bent outer corner portion 3a of the tongue piece 3.

Positioning pins 7e for the upper mold 6 are planted upward from the face surface 7c of the lower mold 7.

Further, an elastic member 9 made of a coil spring or the like is interposed between the upper die 6 and the compression punch 8, and an L-shaped member is formed from the side edge of the upper die 6 to determine the stroke of the compression punch 8. When the arm 6b is extended and the press machine (not shown) is moved upward, the upper mold 6 and the compression punch 8 are integrally separated from the lower mold 7.

Here, 8a is a positioning pin planted on the compression punch 8 with respect to the upper die 6.

Therefore, the lever 1 is placed inside the press die 5 constructed as described above.
When installing, first, the upper mold 6 and the compression punch 8 are moved upward to separate them from the lower mold 7, as shown by the two-dot chain line in FIG.

In this state, the lever 1 is installed in the groove 7a of the lower die 7 by a positioning means (not shown), and the tongue piece 3 is placed in the seat 7.
Position it corresponding to b.

Next, when the press is moved downward, the upper die 6 first contacts the lower die 7 and clamps the lever 1, and then the compression punch 8 moves downward to compress the tongue piece 3.

The tongue piece 3 is plastically deformed as shown by the solid line in FIG. 4 by compression molding by the compression punch 8, and a cylindrical shaft 4 as shown in FIG. 3C is protruded from the edge of the lever 1.

Then, the upper die 6 and the compression punch 8 are moved upward again and the lever 1 is removed.

The press mold used in the compression molding process of the shaft 4 described above is as follows:
If there are multiple tongue pieces, they may be molded at the same time.

Here, when the tongue piece 3 undergoes plastic deformation, it tries to buckle and fold within the hole 6a of the upper mold 6, but the seat part 7b of the lower mold 7
The arcuate portion 7d provided at the tongue portion 3 acts to transfer the force acting on the bent outer corner portion 3a of the tongue piece 3 toward the bent inner corner portion 3b.

Therefore, the meat is forcibly transferred to the bent inner corner 3b of the tongue piece 3, which tends to occur due to folding.
This is particularly effective in the method of forming the shaft, since cracks in the shaft are prevented.

Incidentally, the arc portion 7d may take an approximate form such as an arc shape or a tapered shape, as long as it has the same effect.

In the next step, both end edges 2 of the lever 1 having a protruding shaft 4 are bent, and the axes of both shafts 4 are aligned in a straight line, thereby completing the lever.

The shaft 4 is rotatably supported by a bearing provided in a mechanism (not shown).

FIG. 5 shows another embodiment of the present invention, in which a support is provided protruding from a metal plate.

That is, a rectangular hole 12 for forming a tongue piece similar to the above example is provided in a substrate 11 made of a metal plate, and this rectangular hole 1
The support column 13 is formed from the tongue piece formed on one side of 2 in the same manner as described above.

Note that the shape of the shaft 4 or the support 13 may not be a cylinder but may be a polygonal column, and when protruding from a metal plate, it may not be formed at a right angle but may be formed at an oblique angle.

Furthermore, the metal plate may be formed into a plate shape from a round bar or the like.

In addition, the dance type is not limited to the above-mentioned example,
Other variations are also possible.

As explained above, according to the present invention, since the shaft neck is provided integrally with the metal plate by compression molding, the perpendicularity to the metal plate and the height of the shaft are extremely accurate, and the edge of the metal plate This has the effect that the strength does not decrease even if the structure is protruded from the surface.

Further, since the lower die of the press mold is provided with a substantially arc-shaped portion, a perfectly shaped shaft neck can be easily formed without generating cracks even in one compression molding process.

Furthermore, there is no stagnation of intermediately processed parts, and it is possible to manufacture everything from raw materials to finished products in an integrated process, greatly improving processing accuracy and significantly shortening working time.

[Brief explanation of drawings]

Figures 1 and 2 are cross-sectional views showing the main parts of the conventional example;
Figures a, b, c, and d are explanatory diagrams of processing steps showing one embodiment of the present invention, Figure 4 is a sectional view showing a press die, and Figure 5 is a
FIG. 3 is a perspective view showing another embodiment of the present invention. 1... Lever (metal plate), 2... End edge, 3... Tongue piece, 3a... Bent outer corner, 4... ...Shaft, 5...Press mold, 6...
... Upper die, 6a... Hole, 7... Lower die, 7d... Arc part, 8... Bent compression punch,
13...Curved support.

Claims (1)

[Claims] 1. A metal plate is stamped into a predetermined shape by press working, and at the same time, a tongue piece is integrally punched out on the approximate edge of the metal plate, and the tongue piece is erected by bending, and the height of the erected tongue piece is adjusted. The height is made higher than the height of the final molding of the shaft neck, and then an upper mold having a hole equal to the outer shape of the shaft neck and a corresponding portion of the bent outer corner of the erected tongue piece are formed into a substantially arc shape. The metal plate is held between the metal plate and a lower mold having a circular arc portion, so that the tongue piece is positioned in the hole of the upper mold, and in this state, a compression punch is inserted into the hole of the upper mold. A method for forming a shaft neck protruding from a metal plate, characterized in that the tongue piece is compression molded, and the shaft neck is integrally protruded from substantially the edge of the metal plate.