JPH07121428B2 - Method and apparatus for manufacturing coil spring with small winding diameter - Google Patents

Description

The present invention relates to a method and an apparatus for manufacturing a coil spring having a small winding diameter.

<Prior Art> When manufacturing a conventional coil spring, it is roughly classified into a method of manufacturing by winding a wire rod 1 around a round bar-shaped core metal 2 as shown in FIG. 7, and a method of feeding a wire via a feed roller 3 as shown in FIG. A method has been practiced in which the wire rods 1 that are sent out one after another are bumped through the guide holes 4a of the guide plate 4 against the blocks 5 having curved surfaces and curled one after another.

However, even when any of these methods is carried out, only the winding diameter of the coil spring with respect to the diameter of the wire material can be manufactured to be 3 times or more at most.

Therefore, for example, when manufacturing a dental filler F having a small winding diameter as shown in FIG. 9 (a device for filling a root canal of a tooth with an adhesive), a coil spring having a predetermined diameter is opened and closed at high speed. Insert into the rotating swaging machine mold,
The coil spring housed in the mold is struck and processed several thousand to tens of thousands of times to reduce the winding diameter and manufacture.

<Problems to be Solved by the Invention> However, since a special die must be used when performing such swaging, the die is expensive, and even when processing one coil. Since it has to be struck several thousand to tens of thousands of times, it emits extremely high-pitched sound and may cause noise pollution.Since it requires a large amount of energy, it requires a large motor, etc. Since the material of the coil is work-hardened at a very high level, in the case of the above-mentioned dental filler, there are various problems such as the tip being broken at the time of use and this may get into the root canal and cannot be taken out. there were.

The manufacturing method according to the present invention relates to a completely new technique developed in view of these conventional drawbacks.

<Means for Solving Problems> In the present invention, a coil spring-shaped object having a winding diameter three times or more the wire diameter is rolled while being sandwiched between two opposing surfaces.
A method of manufacturing a coil spring having a small winding diameter, in which the winding diameter of the coil spring-shaped material is reduced by gradually and gradually narrowing the gap between the surfaces, and thereby a coil spring-shaped material having a winding diameter less than 3 times the wire diameter is manufactured. That is the device.

<Operation> As described above, the method according to the present invention rolls while sandwiching a coil spring-like object having a winding diameter three times or more that of a wire rod between two opposing surfaces and gradually separating the distance between these two surfaces. Since it is a method of reducing the winding diameter of the coil spring-like material by gradually narrowing it, it is possible to smoothly reduce the winding diameter without giving extremely large energy to the coil spring-like material, and to process the coil spring-like material. It can be processed without hardening.

Also, the device according to the present invention has a smooth surface as described above.
Since the pressing dies are moved relative to each other, the coil springs are inserted into the smooth surfaces of these pressing dies and rolled while pressing to reduce the winding diameter of the coil springs. There is no need for special and expensive machining dies and large equipment such as a large motor, an inexpensive device can be provided, and there is no fear of generating noise during machining.

<Embodiment> An apparatus for carrying out the manufacturing method according to the present invention will be described with reference to the drawings. 6 and 7 in FIGS.
Are the upper and lower pressing dies, and the upper and lower pressing dies 6, 7
Has a smooth mirror surface on the corresponding surface. The coil spring 8 is placed on a fixed lower pressing die 7, and is gradually pressed while being rolled by the upper pressing die 6 so that the coil spring 8 is rolled in either the left or right direction to be reduced in diameter.

The construction of the vertical pressing molds 6 and 7 is shown in FIGS.
As shown in the figure, the two corresponding surfaces are parallel,
As shown in the vertical pressing dies 6a and 7 shown in FIGS. 3 (A) and 3 (B), the corresponding two surfaces are not parallel to each other. Especially the third
The upper pressing die 6a shown in FIGS. 3A and 3B has a taper formed not only on the lower surface in FIG. The coil spring 8 is constructed so that the diameter thereof can be reduced and the entire conical taper can be performed.

In the case where the corresponding two surfaces of the vertical pressing dies 6 and 7 in the above embodiment are parallel, the upper pressing dies 6 are gradually pressed upward and downward as shown in FIG. It is necessary to move the molds 6 and 7 so that the space between them is reduced, and when the upper pressing mold 6a having an inclined surface on the lower surface is used, the upper pressing mold 6a is moved horizontally as shown in FIG. As a result, the diameter of the coil spring 8 inserted in the vertical pressing molds 6, 6a, 7 can be reduced.

The surfaces of the vertical pressing dies 6 and 7 holding the corresponding coil springs 8 in the above-described embodiments must be smooth, and a good result was obtained particularly when the surfaces were close to a mirror surface.

When the surfaces of the upper and lower pressing dies 6 and 7 are rough, there are drawbacks that the friction when the coil spring extends in the axial direction becomes large as a whole and the wound diameter surface of the coil spring is damaged. Further, when there is a partially rough surface on the surfaces of the vertical pressing molds 6, 7, that is, when there is a portion where the entire coil spring 8 cannot be evenly slipped, there is a drawback of manufacturing a coil spring 8 having a partially different pitch. is there.

Further, when rolling while pressing the coil spring 8 with the upper and lower pressing dies 6, 6a and 7, it is necessary to gradually roll the coil spring 8. Therefore, the pressing of the upper pressing die 6 in the front-lower direction must be gentle. In addition, the inclination of the lower surface of the upper pressing die 6a must be gentle.

In the above embodiment, the flat upper and lower pressing dies 6, 6a, 7 are combined, and the construction is shown in FIG.
As shown in (B), it is possible to combine the rotating disc pressing die 9 and the lower pressing die 10 whose upper surface is curved corresponding to the disc pressing die 9 in combination. Further, it can be configured by combining two disc pressing dies 9 (not shown).

Next, the manufacturing method according to the present invention will be described. In the method according to the present invention, the coil spring 8 manufactured with a winding diameter three times or more the wire diameter is used as the above-mentioned vertical pressing die 6, 6a, 7 or disc pressing die. 9 and the lower pressing die 10 and gradually rolling down between the two surfaces of these dies while narrowing the gap between these two surfaces to gradually reduce the winding diameter of the coil spring 8. This is a method of manufacturing a coil spring having a winding diameter of less than double.

When manufacturing a conical coil spring-like material such as the dental filler F shown in FIG. 9 described above, in particular, FIG. 3 (A), (B) or FIG. 6 (A), (B) It can be easily manufactured by using an apparatus having a pressing type surface having two inclined surfaces in two directions as shown in FIG.

<Effects of the Invention> Since the method and apparatus according to the present invention have the configurations and operations as described above, by implementing the method and apparatus according to the present invention, the equipment cost for the implementation can be significantly reduced, and the apparatus can be manufactured. In this case, noise can be eliminated, and the material of the coil spring-like material can be prevented from being unnecessarily work-hardened and easily broken, and the winding diameter of the coil spring-like material can be easily tripled with respect to the diameter of the wire. The coil spring-like material having a small winding diameter and having a conical shape as a whole can be easily manufactured at low cost in large quantities as required.

[Brief description of drawings]

1 to 3 (A) and (B) are explanatory views showing an example of the apparatus of the present application, FIGS. 4 and 5 are explanatory views showing the moving direction of the pressing die, and FIG. 6 (A), (B) is an explanatory view showing a pressing die of another example, FIGS. 7 and 8 are explanatory views showing a conventional coil spring manufacturing method, and FIG. 9 is a side view of a dental filler. 1 is a wire rod, 2 is a core metal, 4 is a guide plate, 5 is a block, 6,6
Reference numerals a, 7, 9, 10 are pressing types, and 8 is a coil spring.

Claims (4)

[Claims] 1. A coil spring-like material having a winding diameter three times or more the wire diameter is rolled while being sandwiched between two opposing surfaces, and the gap between the two surfaces is gradually and gradually narrowed to gradually reduce the coil spring-like material. The winding diameter is reduced, and this reduces the wire diameter to 3
A method for manufacturing a coil spring having a small winding diameter, characterized in that a coil spring-shaped material having a winding diameter less than twice is manufactured. 2. A pair of pressing dies having corresponding smooth surfaces are configured to be relatively movable, and the corresponding smooth surfaces gradually narrow gradually as they further move. Coil spring manufacturing equipment. 3. The coil spring manufacturing apparatus according to claim 2, wherein at least one of the two relatively moving pressing type smooth surfaces is configured to be endless. 4. An inclined surface is formed in at least one of the two relatively moving pressing-type smooth surfaces in a moving direction and in a direction at right angles to the moving direction. The manufacturing apparatus of the coil spring according to the second aspect.