JPH0424213B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field of the Invention] The present invention relates to a belt such as a watch band or a waist belt, and a manufacturing method thereof.

[Prior art and problems]

2. Description of the Related Art Conventionally, synthetic resins have been widely used, for example, as watch bands and waist belts. The materials used include vinyl chloride, nylon, polyurethane, etc., but vinyl chloride belts are made of soft vinyl chloride laminated together or have a sponge inserted between them to make them feel good against the skin. is used. As a result, the hole in the belt for the needle was weak, making it easy to avoid and looking unsightly, resulting in a short period of use.

In addition, belts made of nylon have the disadvantage of not being weather resistant and discolor easily, and belts made of hard polyurethane have the disadvantage of being uncomfortable to the touch and being uncomfortable to use, although the needle stopper part of the belt is strong. was.

[Object of the present invention]

The present invention was made in view of the above-mentioned circumstances, and an object of the present invention is to provide a belt that is comfortable to the touch, durable, and has good decorative properties.

[Summary of the Invention] In order to achieve the above-mentioned object, the present invention has a belt-shaped belt-shaped soft synthetic resin member, and a hard synthetic resin member that is integrally welded to the inside of the belt-shaped soft synthetic resin member. A plurality of protrusions are formed at predetermined intervals, and fixing holes into which pins for fixing the belt are inserted are formed vertically through the plurality of protrusions, and the soft synthetic resin member is replaced with a hard synthetic resin member. It is formed so as to cover the lower surface of the holder except for the surfaces of the plurality of protrusions.

[Example] Hereinafter, an example of the present invention will be described using a method of manufacturing one end portion of a watch strap as an example.

In Fig. 1, reference numeral 1 denotes a well-known injection molding machine used for injection molding of multicolor or multi-material materials, and this injection molding machine 1 is used for injection molding of thermoplastic synthetic resin for primary molding and thermoplastic synthetic resin for secondary molding. The injection devices 2 and 3 for supplying resin are equipped facing each other, and a rotating device 6 equipped with a moving mold 4 and an ejector device 5, a mold clamping device (not shown), and a mold opening device (not shown) ) etc.

In addition, as a mold for molding, 2 molds are used as shown in Figure 1.
A cavity 7 (the mold is not shown) in which the stopper hole of the belt and its surrounding area (hereinafter referred to as primary molding part A) are formed in the movable molds 4-A and 4-B of the same shape; A primary molding mold 8 and a secondary molding mold 9 are used.

First, the two movable molds 4 mounted on the rotating device 6 of the injection molding machine 1 shown in FIG.
-A, 4-B, one of the movable molds 4-A is moved by a mold clamping device (not shown), and the primary molding mold 8 having a cavity 10 that is to form a contact surface with a secondary molding member B, which will be described later, is , keep the corresponding mold clamped. Then, from the injection device 2 for synthetic resin for primary molding, under predetermined heating and pressurizing conditions, a molten material having a harder hardness than the soft polyurethane for secondary molding [temperature near the nozzle of the injection device, e.g. ~200° C.] to form a primary molded member A consisting of a stopper hole 20 and its peripheral portion 21 as shown in FIG.

The thickness of the primary molded member A is approximately 1.5 mm, and the hole 2
The peripheral portion 21 of 0 is a thin piece that protrudes about 1 mm.

Next, when the primary molding mold 8 is opened by a mold opening device (not shown), the cavity 7 of the movable mold 4-A is opened.
The primary molded member A is held inside.

Next, it is necessary to quickly inject the secondary molding resin to integrally mold the primary molded member A before the temperature of the primary molded member A decreases, that is, before the primary molded member A completes shrinking. . As a method for this, in this embodiment, the rotating device 6 is rotated 180 degrees to the left to make the right movable mold 4-A correspond to the secondary molding mold 9, and the left movable mold 4-A is made to correspond to the secondary molding mold 9.
-B is made to correspond to a primary molding die, and these, primary molds, and secondary molding molds 8 and 9 having cavities 11 are clamped by the mold clamping device (not shown). Then, a molten product of a secondary molding resin, which is a soft polyurethane similar to the primary molding resin and has a hardness about 10 to 25 degrees lower than the primary resin, is injected from the injection device 3 under predetermined heating and pressurizing conditions. , the secondary molded member B forming the belt body 22 as shown in FIG. 3 is formed, and the primary molded member A is further embedded in the secondary molded member B as shown in FIGS. 4 to 7. Weld them together in such a way (the joint surfaces of the two are welded by a certain degree of melting), so that the band piece C on the stopper hole side of the watch strap corresponds to the secondary molding mold 9 on the left side of the injection molding machine 1. It is molded in the position where it will be.

The size of the stop hole 20 in the primary molded member A portion of the stop hole side band piece C is about 2 mm in diameter, and the interval pitch between each stop hole 15 is 6.5 mm to 7.0 mm,
Also, the width is 12mm. Further, the thickness of the secondary molded member B is approximately 2.0 mm to 2.6 mm. In addition, 2 in Figure 3
2 is a spring bar device hole for connecting the watch body and the band.

In addition, as an example of the hardness of polyurethane, the soft polyurethane for the primary molded member A is approximately 90 degrees on the JIS Shore A scale, and the soft polyurethane for the secondary molded member is approximately 80 degrees on the JIS Shore A scale.
A difference of about 10 degrees seemed to be appropriate, but the hardness is 65 degrees to 95 degrees, and there was no problem if the difference was within the range of 10 degrees to 25 degrees. At the same time, on the right side,
The above-mentioned melted material of the soft polyurethane for primary molding with high hardness is injected from the injection device 2, and the above-mentioned primary molded member A is molded.

Next, the secondary molding mold 9 is opened, and the movable mold 4
- Rotary valve 1 installed on the A side
2-A is rotated to supply oil from the oil supply pipe 13-A and operate the ejector 5-A, thereby producing a band piece on the fastening hole side of the watch strap, in which the primary and secondary molded members A and B are integrally welded. Extrude C. Further, the same rotary valve 12-A is rotated to supply oil from the oil supply pipe 14-A and return the ejector 5-A to its original position. Therefore, the cavity 7-A of the movable mold 4-A becomes empty and is restored to a state where it can be molded at any time.
Moreover, the primary molding mold 8 is also opened.

Then, the rotating device 6 is rotated 180 degrees to the left again.
Therefore, on the right side of the rotating device 6, the movable mold 4-A of the vacant cavity 7-A and the primary molding mold 8 correspond to each other, and on the left side, the primary molding member is placed in the cavity 7-B. Moving mold 4 holding A
-B and the secondary molding mold 9 are located in corresponding positions. Therefore, as described above, after clamping the primary and secondary molding molds 8 and 9, the primary molding resin is injected from the injection device 2, the secondary molding resin is injected from the injection device 3, and the right side While forming the primary molded member A, on the left side, a secondary molded member B is formed, and after welding this and the primary molded member A to form a band piece C on the fastening hole side of the watch strap, the primary and secondary molded members are formed. The molding molds 8 and 9 are opened, and the ejector 5-A or 5-B corresponding to the secondary molding mold 9 is operated to push out the band piece C on the fastening hole side of the watch strap. Repeat the series of operations. In this way, the primary member A and the secondary member B are welded together, and the stopper hole side band piece C of the watch strap is automatically and continuously manufactured.

In this example, after forming the primary molded member A, the secondary molded member B is formed, and both members are welded. However, conversely, the secondary molded member B is
Of course, after molding, the primary molded member A may be formed and both members may be welded. In addition, in this example, a similar thermoplastic synthetic resin of polyurethane was used for the primary molded member A and the secondary molded member B.
It goes without saying that the present invention is not limited to this, and that the two members may be made of different materials, for example, polyurethane may be used for the primary molded member A, and vinyl chloride may be used for the secondary molded member. And the material is
Examples include polyethylene, polyurethane, vinyl chloride, perplane, silicone, polyester, nylon, etc., and the appropriate hardness range is 75° to 95°. Furthermore, in this example, thermoplastic synthetic resins of the same color and different hardness were used for the primary molded member A and the secondary molded member B, but if a secondary resin of a different color and lower hardness than the primary resin was used. , we can produce two-color watch straps.

Further, in this embodiment, an example of manufacturing the band piece C on the fastening hole side of a watch strap is shown, but the invention is not limited to this, and as shown in FIGS. 8 and 9, the buckle side of the watch belt It goes without saying that the band piece D can be manufactured by the same method, and can also be widely used as various belts such as clothing belts and bag belts.

Furthermore, although this embodiment shows an example in which the present invention is applied to a belt having a stopper hole 20, it goes without saying that the present invention can also be applied to the production of a richly colored belt without a stopper hole.

In addition, although the manufacturing method using injection molding is shown in this example, it is needless to say that the method is not limited to this, and for example, a hot press molding method is also possible.

[Effects of the present invention] As described above, according to the present invention, the lower surface of the belt is made of a soft synthetic resin except for the area around the stopper hole, so it feels very good to the touch, and the stopper into which the pin for fastening the belt is inserted is made of soft synthetic resin. The hole is made of hard synthetic resin, and the area around the entrance of the stopper hole where the most force is applied is made of hard synthetic resin, so the stopper hole will deform.
It is possible to prevent breakage and improve durability, and since the bottom surface of the hard synthetic resin member is uneven, it has the advantage of good adhesion to the soft synthetic resin.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional explanatory diagram showing the molding relationship between a molding machine and a molded member to illustrate the manufacturing method of the present invention, FIG. 2 is an enlarged central cross-sectional view of the primary molded member with some parts omitted, and FIG. FIG. 4 is a partially omitted enlarged central cross-sectional view of the secondary molded member; FIG. 4 is a partially omitted enlarged plan view showing band piece C on the fastening hole side of the watch strap; FIG. The figure is an enlarged sectional view taken along the line C-C in Fig. 4, Fig. 7 is an enlarged sectional view taken along the line D-D in Fig. 4, and Fig. 8 is an enlarged plan view showing the buckle side band piece D of the watch strap. , FIG. 9 is a front view of FIG. 8. 2, 3... Injection device, 4-A, 4-B... Moving mold, 5-A, 5-B... Ejector device, 6...
... Rotating device, 7-A, 7-B... Cavity, 8
...Mold for primary molding, 9...Mold for secondary molding, 1
0, 11...Cavity, 12-A, 12-B...
...Rotary valve, 13,14...Oil supply pipe, A
... Member for primary forming, B... Member for secondary forming, C
...Band piece on the fastening hole side of a watch strap.

Claims (1)

[Scope of Claims] 1. Consists of a soft synthetic resin member having a belt-shaped outer shape, and a synthetic resin that is integrally welded to the inside of the soft synthetic resin member and has a higher hardness than the soft synthetic resin member. The lower surface of the hard synthetic resin member has a plurality of protrusions formed at predetermined intervals along its length, and a pin for fixing the belt is inserted into the plurality of protrusions. A belt is provided with a stopper hole extending vertically through the belt, and the soft synthetic resin member is formed to cover the lower surface of the hard synthetic resin member except for the surfaces of the plurality of protrusions. 2. The belt according to claim 1, wherein the soft synthetic resin member and the hard synthetic resin member are made of different colored synthetic resins. 3. The belt according to claim 1, wherein the difference in hardness between the soft synthetic resin member and the hard synthetic resin member is 25° or less.