JPS6334756Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a caulking device, and particularly to an efficient caulking device that can caulk at once without requiring a preliminary process.

A part that has a cylindrical protrusion longer than the wall thickness of the object to be attached in a through hole formed in the object to be attached,
There are cases where the cylindrical projection is inserted and caulked. In this kind of caulking work, in order to obtain good caulking quality without cracks or wrinkles, it is necessary to perform a preliminary process of expanding the tip of the cylindrical protrusion, and then press the cylindrical protrusion and caulk it. Therefore, in conventional caulking devices,
Two types of equipment were required, each equipped with a punch for the preliminary process and a punch for the subsequent caulking. Therefore, a large number of man-hours and a large number of devices are required, making it difficult to reduce the cost of caulking. For example, when a reinforcing component 3 having a cylindrical protrusion 2 as shown in FIGS. 6 and 7 is caulked to the periphery of a through hole 6 formed in the center of a dust cover 5 for a disc brake, First, as shown in FIG. 8, the tip of the cylindrical protrusion 2 protruding from the through hole 6 is expanded using a preliminary process punch 7, and then, as shown in FIG. By crushing the expanded cylindrical projection 2 with a caulking punch 8 having a pressing surface, the reinforcing component 3 is
is caulked to the peripheral edge of the through hole 6 of the dust cover 5.

The present invention was developed against the background of the above-mentioned circumstances, and its purpose is to form a part having a cylindrical protrusion on an object to be attached without requiring equipment or work for preliminary process. To provide a caulking device capable of caulking the periphery of a through hole all at once.

In order to achieve the above object, the present invention provides a method for manufacturing a molded product comprising the steps of: (1) an upper die holding member and a lower die holding member which are movable toward and away from each other; (2) an upper die punch and a lower die punch which are provided on the upper die holding member and the lower die holding member, respectively, and each having an opposing annular pressing surface for pressing the periphery of a through hole; (3) an inner punch which is movable relative to the upper die punch in the pressing direction and which, while protruding from the upper die punch, is fitted into a circular hole opening on the inside of the annular pressing surface of the upper die punch, and which has a tip portion which can be fitted into the cylindrical protrusion and a tapered portion which is continuous with the tip portion and which becomes larger in diameter as it approaches the upper die punch; and (4) When the upper die holding member and the lower die holding member are brought close to each other and the inner punch is fitted into the cylindrical protrusion, the tapered portion of the inner punch applies a preload to the inner punch in a pressing direction that can expand the tip of the cylindrical protrusion, and when a reaction force exceeding the preload is applied to the inner punch, an elastic member is included that allows the inner punch to move into the upper die punch.

In this way, when the upper mold holding member and the lower mold holding member are brought relatively close to each other, the tapered part of the inner punch first expands the tip of the cylindrical protrusion protruding from the through hole; When this is completed, the inner punch is pushed into the upper punch according to the reaction force applied to the inner punch, and the expanded cylindrical projection is pressed against the peripheral edge of the through hole by the annular pressing surface of the upper punch. The parts can be caulked all at once to the periphery of the through hole formed in the object to be attached. Therefore, since caulking is performed with one device, the number of man-hours and number of devices are reduced by approximately 1/2.
2, and the cost for caulking can be greatly reduced.

Hereinafter, an embodiment of the present invention will be described in detail based on the drawings.

In FIG. 1, 10 and 12 are an upper mold holding member and a lower mold holding member of a press device (not shown), and for example, the upper mold holding member 10 is connected to the lower mold holding member 12.
It is designed to be driven in a direction approaching .
The upper mold holding member 10 and the lower mold holding member 12 are respectively provided with opposing annular pressing surfaces 14 and 16 for pressing the periphery of the through hole 6 formed in the dust cover 5 which is the object to be attached. An upper die punch 18 and a lower die punch 20 are fixed by bolts 22 and 24.

A bottomed circular hole 26 is formed inside the annular pressing surface 14 of the upper punch 18, and the inner punch 28, which has a thick bottomed cylindrical shape, can slide with its opening facing downward. The upper die punch 18 is inserted into the upper die punch 18 by a bolt 30 that passes through its center and is screwed into the upper die punch 18.
It is supported so that it can freely move relative to the upper punch 18 by a certain distance in the pressing direction and protrudes downward from the upper die punch 18. The inner punch 28 has a tip portion (lower end portion) 32 having a diameter that can be inserted into the cylindrical projection 2;
Continuing from the tip 32, there is a tapered part 34 that becomes larger in diameter as it approaches the upper die punch 18. A urethane rubber 36 as an elastic member is inserted between the inner punch 28 and the upper punch 18 in the bottomed circular hole 26.

The urethane rubber 36 allows the tapered portion 34 to fit into the cylindrical projection 2 when the upper mold holding member 10 and the lower mold holding member 12 are brought close together and the tip 32 of the inner punch 28 is fitted into the cylindrical projection 2. When a preload in the pressing direction that can expand the tip of the inner punch 28 is applied to the inner punch 28, and a reaction force exceeding the preload is applied to the inner punch 28, the inner punch moves into the upper punch 18 due to elastic deformation. It is constructed to allow movement.

A bottomed circular hole 38 is formed inside the annular pressing surface 16 of the lower punch 20 and has a diameter into which the tip 32 of the inner punch 28 can be fitted.
An annular stopper 40 is fixed to the bottom of the inside 8 with a bolt 42. That stopper 40
is in contact with the lower end surface of the inner punch 28 to prevent the inner punch 28 from descending when the tapered portion 34 of the inner punch 28 finishes expanding the cylindrical projection 2. In addition, 44 is the lower die punch 20
A positioning protrusion fixed to the dust cover 5 that engages with a tightening hole 46 provided in the dust cover 5 to position the dust cover 5 at a caulking position coaxial with the upper die punch 18 and the lower die punch 20. It is.

Next, the operation of the caulking device configured as above will be explained.

First, prior to caulking, with the cylindrical protrusion 2 fitted into the through hole 6, the dust cover 5 is positioned on the lower die punch 20 using the positioning protrusion 44. FIG. 2 shows this state.

Next, as the upper mold holding member 10 is driven toward the lower mold holding member 12, the upper mold punch 18 and the inner punch 28 are driven toward the lower mold punch 20. In this state, first, the tip 32 of the inner punch 28 is fitted into the cylindrical projection 2. Subsequently, when the tapered portion 34 reaches the upper end of the cylindrical projection 2, the cylindrical projection 2 is expanded along the inclined surface of the tapered portion 34. That is, the cylindrical protrusion 2 is expanded at an angle of about 45 degrees with respect to the outer peripheral surface of the inner punch 28, similar to the inclination of the tapered portion 34, and when the lower end of the inner punch 28 comes into contact with the stopper 40 and is stopped, Almost the entire cylindrical projection 2 is expanded. FIG. 3 shows this state.

When the inner punch 28 comes into contact with the stopper 40, the urethane rubber 36 is elastically deformed by the reaction force applied to the inner punch 28, and the inner punch 28 is pushed into the upper punch 18. Therefore, the upper die punch 18 approaches the lower die punch 20, and the cylindrical projection 2, which has already been expanded, is pressed against the peripheral edge of the through hole 6 by the pressing surface 14 of the upper die punch 18. As a result, the cylindrical projection 2 and the dust cover 5 at the peripheral edge of the through hole 6 are strongly sandwiched between the pressing surfaces 14 and 16, so that the reinforcing component 3 is caulked to the dust cover 5. FIG. 4 shows this state, and the dust cover 5 shown in FIG. 5 shows a product state in which the reinforcing component 3 is crimped.

In this way, according to this embodiment, the upper die holding member 1
0 is driven toward the lower mold holding member 12, caulking, which conventionally required a preliminary step to expand the cylindrical protrusion 2, is performed all at once, making the work much easier. This improves efficiency and reduces the number of equipment in half. Therefore, the cost for caulking is greatly reduced.

Although the embodiment of the present invention has been described above based on the drawings, the present invention can also be applied to other aspects.

For example, a compression coil spring may be used instead of the urethane rubber 36. In short, the elastic member applies a preload to the inner punch 28 that allows the cylindrical protrusion 2 to expand, and also allows the inner punch 20 to move into the upper punch 18 when a reaction force exceeding the preload is applied. That's fine.

In the above description, the upper mold holding member 10 is driven toward the lower mold holding member 12, but the lower mold holding member 12 may be driven toward the upper mold holding member 10 conversely.

Further, the inclination angle of the tapered portion 34 can be variously selected depending on the thickness, material, etc. of the cylindrical projection 2, and when the expansion of the cylindrical projection 2 at the tapered portion 34 is completed, If sufficient reaction force is obtained from the lower die holding member 12, the stopper 40 may not be provided.

The above-mentioned embodiment is merely one embodiment of the present invention, and various modifications may be made to the present invention without departing from the spirit thereof.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a main part of a caulking device showing an embodiment of the present invention. Figures 2 to 4 show the first
FIG. 3 is a process explanatory diagram of caulking using the device shown in the figure. FIG. 5 is a partial cross-sectional view showing a dust cover with reinforcing parts crimped using the apparatus of FIG. Fig. 6 is a perspective view of the reinforcing parts;
The figure is a longitudinal sectional view of the part of FIG. 6. FIG. 8 and FIG. 9 are diagrams showing a preliminary process and a caulking process of conventional caulking, respectively. 2... Cylindrical projection, 3... Reinforcement part (component),
5...Dust cover (attached object), 6...Through hole,
10... Upper die holding member, 12... Lower die holding member,
14, 16... Annular pressing surface, 18... Upper die punch, 20... Lower die punch, 26... Bottomed circular hole (circular hole), 28... Inner punch, 32... Tip part,
34...Tapered portion, 36...Urethane rubber (elastic member).

Claims (1)

[Claims for Utility Model Registration] A device for caulking a part having a cylindrical protrusion longer than the wall thickness of the object to be attached to the periphery of a through hole formed in the object to be attached, the device relatively approaching and separating. an upper die holding member and a lower die holding member which are respectively provided on the upper die holding member and the lower die holding member and each having opposing annular pressing surfaces for pressing the periphery of the through hole; A die punch and a lower die punch are movable relative to the upper die punch in the pressing direction, and protrude from the upper die punch into a circular hole opened inside the annular pressing surface of the upper die punch. an inner punch having a tip that can be fitted into the cylindrical protrusion and a tapered portion that becomes larger in diameter as it approaches the upper die punch following the tip; and the upper die holding member and the lower die. When the inner punch is fitted into the cylindrical projection with the mold holding member brought close to each other, the tapered portion of the inner punch applies a preload to the inner punch in the pressing direction that can expand the tip of the cylindrical projection. and an elastic member that allows the inner punch to move into the upper die punch when a reaction force exceeding the preload is applied to the inner punch, the upper die holding member and the lower die holding member By a single relative approach operation with the through hole, the tip of the cylindrical protrusion protruding from the through hole is expanded and simultaneously pressed against the periphery of the through hole, thereby caulking the part to the object to be attached at once. A caulking device characterized by: