JPH04125125A - Manufacture of hollow molding - Google Patents

Abstract

PURPOSE:To manufacture a hollow molding of complicated three-dimensional shape with increased strength by disposing a tube in a space formed by a mold, covering the tube with an expansible base cloth, impregnating the same with synthetic resin properly and injecting air. CONSTITUTION:A space 2 is formed by combining a plurality of molds 1 having recessed sections 1a processed into optional shape. A tube 3 of optional shape or of almost similar shape of the space is disposed in said space 2, and an end 3a of said tube 3 is fixed through a nozzle 4 disposed on a fixing section 1c and the end 1b of the mold 1. Said tube 3 is covered with an expansible base cloth 5, and an end 5a of the base cloth 5 is also fixed through a nozzle 4 disposed on a fixing section 1c formed in the mold 1. Then, the base cloth 5 is impregnated with synthetic resin 6 by an optional means, and the mold 1 is clamped, and air is injected into the tube 3 through the nozzle 4 and expanded therein, and the expansible base cloth 5 is pressed to the wall face of the mold 1 and hardened to manufacture a hollow molding 7. The hollow molded body of complicated shape can be molded extremely easily by said arrangement.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to improvements in the manufacturing method of hollow molded articles, blow molded baseball gloves, and gloves.

(Prior Art) Conventionally, various methods have been invented as methods for manufacturing hollow molded bodies using synthetic resins.

That is, rotary molding, slush molding, blow molding, injection molding, fluidized immersion molding, etc. are known.

These molding methods allow the molding of synthetic resin molded products regardless of whether they are hard or soft, but these conventional molding methods are limited to molding of a single material.

(Problems to be Solved by the Invention) These conventionally known molding methods are limited to molding methods using a single material as described above, and therefore have the following problems.

That is, by using a method such as rotational molding, slush molding, or blow molding, using a soft material, a complex-shaped hollow molded product with softness, texture, and flexibility comparable to artificial leather or synthetic leather can be obtained. However, on the other hand, the strength of the obtained hollow molded body, especially the tensile strength and tear strength, was far inferior to that of artificial leather or synthetic leather.

On the other hand, is it possible to improve the tensile strength and tear strength to some extent in injection molding with a base fabric inserted or fluidized dip molding in a form where the base fabric is covered? On the contrary, there was a problem in that hollow molded bodies with complicated shapes could not be made.

It is also possible to use artificial leather or synthetic leather and form it by thermoforming such as vacuum forming, pressure forming, or hot press forming. However, the molding of hollow molded bodies is
It was impossible.

Although it is possible to weld the material into the form of a bag by welding, it has not been possible to form a hollow molded product with a three-dimensional appearance.

(Means for Solving the Problems) In view of these conventional drawbacks, the present invention aims to improve tensile strength and tear strength, and to provide a method for manufacturing a hollow molded product with a complex three-dimensional shape. It has been done.

That is, a tube having an arbitrary shape or substantially similar to the shape of the cavity is arranged in a cavity formed by combining a plurality of molds having recesses of arbitrary shapes, and the ends of the tubes are arranged in a cavity formed by combining the molds. The tube was fixed via a nozzle placed in a fixing part formed at the end of the mold, and then the tube was covered with a stretchable base fabric, and the end of the base fabric was also formed on the mold. The base fabric is fixed via a nozzle arranged in the fixing part, the base fabric is impregnated with a synthetic resin by any means, the mold is clamped, and air is injected into the tube through the nozzle to inflate it, so that the elastic tube can be expanded. This is a method for manufacturing a hollow molded body, characterized in that the base fabric is pressed against the wall surface of the mold and cured to manufacture a hollow molded body.

Furthermore, as another form, for example, a plurality of molds having the shape of a baseball glove and a tube having an arbitrary shape or substantially similar to the shape of the baseball glove are provided in the cavity formed by combining the molds. The end of the tube is fixed via a nozzle placed in a fixing part formed at the end of the mold, and then the tube is covered with a stretchable base fabric and The end of the base fabric is also fixed via a nozzle placed in a fixing part formed in the mold, the base fabric is impregnated with a synthetic resin by any means, the mold is clamped, and the nozzle is passed through the tube. A method for producing a blow-molded baseball glove, comprising: injecting and expanding air, pressing the stretchable base fabric against the wall surface of the mold, and curing the fabric to produce a blow-molded baseball glove. .

In addition, in the method for manufacturing a hollow molded body according to the present invention,
As the tube, it is possible to appropriately select and use a chloroprene-based rubber or other rubber having good heat resistance and elasticity, or a heat-resistant synthetic resin such as polyamide or polyester.

In addition, as the stretchable base fabric, rubber knitting, knit, needle felt, non-woven fabric, and other base fabrics with good stretchability can be used, and woven fabrics using stretchable threads can also be used. It is possible.

In addition, by using a synthetic resin used in the present invention that is flexible even after curing and has good adhesion to the base fabric, it is also possible to bond the base fabric in layers. Become. For example, it is desirable to use a vinyl chloride paste sol solution, a two-component type polyurethane resin, or the like.

Furthermore, regarding the method for manufacturing a baseball club of the present invention, it is possible to integrally mold the main body of the baseball club and the web at the same time, or it is possible to mold the web separately and attach it to the main body of the baseball club later by any method. is also possible. However, it is better to form the web separately and attach it to the body of the baseball club later, which increases the degree of freedom in design when considering the shape, strength, design, etc. of the web, and provides a variety of baseball gloves. It is possible.

(Function) Since the present invention has the above configuration, it exhibits the following effects.

That is, the shape of the tube placed in the cavity formed by the mold is arbitrary or has a shape that is approximately similar to the shape of the cavity, and the tube is further coated with a stretchable base fabric. By injecting air into the tube after impregnating it with a synthetic resin, the air flows into the tube, and the tube expands into the shape of the cavity formed by the mold. By making the cavity shape approximately similar to the shape of a baseball glove (for example, the shape of a baseball glove), it expands along the mold shape. It can be molded extremely easily.

In addition, in the method for producing a hollow molded body and a baseball glove according to the present invention, it is possible to mold a thin hollow molded body and a blow molded baseball glove, which was impossible with conventional molding methods, by using a stretchable base fabric. This is possible by using a method of inflating a tube, so the strength can be freely set by appropriately changing the thickness of the base fabric.

Furthermore, in the method for producing a hollow molded article of the present invention, by appropriately selecting the characteristic values of the base fabric, it is possible to improve the tensile strength and tear strength, and also to increase the degree of vertical and horizontal expansion and contraction of the base fabric. Since it can be changed, the degree of expansion and contraction of the hollow molded body itself can also be changed.

Also, by forming a recess in the mold during molding and inserting another part into the recess and molding, for example, hollow molded bodies or hollow molded baseball clubs having parts in various colors can be supplied. It is something that can be done.

Furthermore, if the hollow molded body is manufactured according to the manufacturing method of the present invention after applying the gel coat to the inner surface of the mold, the color tone of the gel coat can be varied in various ways, thereby producing various colored hollow molded bodies and hollow molded bodies. In addition to supplying baseball gloves, we can also supply gloves with good surface conditions.

Furthermore, in the present invention, by changing the expansion coefficient of the tube used on the front side and the rear side of the hollow molded body,
The way the tube expands changes, and when performing blow molding, for example, if the degree of protrusion is large, increasing the expansion coefficient of the tube will allow it to better conform to the shape of the mold. In addition, in the present invention, the tensile strength and tear strength can be further improved by making the shape of the base fabric seamless.

In addition, in the present invention, if a synthetic resin with good adhesive properties is used, it becomes possible to laminate base fabrics, and the strength can be further improved.

In addition, in the method for manufacturing a blow-molded baseball club of the present invention, the web can be integrally molded at the same time.
It is also possible to form the web separately and then attach it to the baseball club body.

By doing so, the degree of freedom in designing the baseball club is significantly improved.

(Embodiment) An embodiment of the present invention will be described based on the drawings, in other words, as shown in FIGS. , a tube 3 having an arbitrary shape or substantially similar to the shape of the cavity is arranged in a cavity 2 formed by combining the molds 1, and an end 3a of the tube 3 is connected to an end 1b of the mold 1. The tube 3 is fixed via a nozzle 4 disposed on the fixed portion 1c, and the tube 3 is covered with a stretchable base cloth 5.
The end portion 5a is also fixed via a nozzle 4 disposed on a fixing part 1c formed in the mold 1, and the base fabric 5 is impregnated with a synthetic resin 6 by any means, and the mold 1 is clamped, A hollow molded body characterized in that air is injected into the tube 3 through a nozzle 4 to expand it, press the stretchable base fabric 5 against the wall surface of the mold 1, and harden it to produce a hollow molded body 7. This is the manufacturing method.

In addition, as another form of the present invention, a plurality of molds 1 having the shapes of baseball gloves shown in FIGS. A tube 3 having a shape substantially similar to the cavity 2 is arranged, and the end 3a of the tube 3 is fixed via a nozzle 4 arranged in a fixing part IC formed at the end 1b of the mold 1. At the same time, the tube 3 is covered with a stretchable base fabric 5, and the end portion 5a of the base fabric 5 is also fixed via a nozzle 4 disposed in a fixing part IC formed in the mold 1, and the base fabric 5 is impregnated with synthetic resin 6 by any means, and the mold 1
is compressed, air is injected into the tube 3 through the nozzle 4 to expand it, and the stretchable base fabric 5 is pressed against the wall surface of the mold 1 and hardened to produce a blow-molded baseball glove 7A. This is a method for manufacturing a hollow-molded baseball glove.

In addition, in the present invention, by appropriately forming ventilation holes 1d in the mold 1, the air inside the mold can be discharged, and the moldability of the hollow molded product and the like can be further improved.

Further, in the present invention, the tube 3 and the base fabric 5 are attached to the nozzle 4.
In order to attach and fix the nozzle 4, the nozzle 4 portion is removed after molding hardens, which further improves productivity.
Since the nozzle itself can be made of synthetic resin, production costs can also be reduced.

In addition, as shown in Figures 5 and 6, only the main body of a hollow-molded baseball glove can be molded, the web can be molded separately, and it can be attached later by any method; However, it is also possible to integrally mold the web at the same time when molding the baseball glove.

Note that although the drawings are omitted, the manufacturing method for baseball gloves is also the same.

(Effects of the Invention) Since the present invention has the above configuration, it has the following effects.

That is, in the method for manufacturing a hollow molded article and a blow molded baseball glove of the present invention, the shape of the tube is made to be an arbitrary shape or approximately similar to the shape of the cavity formed by the mold, so that the base can be expanded and contracted. Because the cloth is pressed against the wall of the mold,
Since the tube expands along the shape of the mold, it has the effect of making it possible to extremely easily mold hollow molded objects and hollow molded baseball gloves with complex shapes that closely match the shape of the mold. .

In addition, in the manufacturing method of the hollow molded article and the blow molded baseball glove according to the present invention, it is possible to mold to a thin wall, which is impossible with conventional molding methods, or to inflate a stretchable base fabric and a tube. By changing the thickness and elasticity of the base fabric, it is possible to improve the tensile strength and tear strength, and it is also possible to create hollow molded bodies and hollow baseball gloves with various characteristic values. It can be molded.

Also, by forming a recess in the mold during molding and inserting another part into the recess and molding, for example, hollow molded bodies or hollow molded baseball clubs having parts in various colors can be supplied. It is something that can be done.

Furthermore, if the hollow molded body is manufactured according to the manufacturing method of the present invention after applying a gel coat to the inner surface of the mold, the color tone of the gel coat can be changed in various ways, thereby producing various colored hollow molded bodies and hollow molded bodies. In addition to being able to supply baseball gloves, it also has the advantage of being able to supply gloves with good surface conditions.

Furthermore, in the present invention, by changing the expansion coefficient of the tube used at a desired location, the way the tube expands can be changed. If the expansion coefficient of the tube is increased, it will be easier to follow the shape of the mold, and moldability will be further improved.

In addition, in the method for manufacturing a blow-molded baseball glove of the present invention, the web can be integrally molded at the same time, and the web can be molded separately and later attached to the main body of the baseball glove. By doing so, the flexibility in designing the baseball glove is significantly improved.

As described above, the method for manufacturing a hollow molded body of the present invention has effects not found in conventional blow molding methods.

[Brief explanation of the drawing]

1 to 4 are cross-sectional views of essential parts showing one step of the method for manufacturing a hollow molded body according to the present invention, and FIGS. 5 to 6 are cross-sectional views of a blow molded body according to another embodiment of the present invention. FIG. 7 is a perspective view showing a method for manufacturing a blow-molded baseball glove according to another embodiment of the present invention, and FIG. 8 is a perspective view showing the front and back sides of a baseball glove. FIG. 9 is a plan view showing a tube used in a blow-molded baseball club according to an embodiment of the present invention covered with a base fabric, and FIG. 9 shows a method for manufacturing a blow-molded baseball glove according to another embodiment of the present invention. Enlarged cross-sectional view of main parts. 1: Mold, 1a: Recess, 1b end, IC: Fixed part, 1
d: ventilation hole, 2: void, 3 tube, 3a: end,
4: Nozzle, 5: Base fabric, 5a: End, 6: Synthetic resin, 7
: Hollow molded body, 7A: Baseball glove.

Claims (1)

[Scope of Claims] 1. A tube is placed in a cavity formed by combining a plurality of molds having recesses processed into arbitrary shapes and the molds, and the end of the tube is inserted into the mold. The tube is fixed via a nozzle placed in a fixing part formed at the end of the tube, and then the tube is covered with a stretchable base fabric, and the end of the base fabric is also placed in the fixing part formed in the mold. Further, the base fabric is impregnated with a synthetic resin by any means, the mold is clamped, and air is injected into the tube through the nozzle to inflate the stretchable base fabric. A method for manufacturing a hollow molded body, characterized in that the hollow molded body is manufactured by pressing against the wall surface of the mold and curing the hollow molded body. 2. The method for producing a hollow molded body according to claim 1, wherein the shape of the tube disposed in the cavity formed by the mold is substantially similar to the shape of the cavity formed by the mold. 3 A plurality of molds having the shapes of baseball gloves, mitts, etc., and a tube placed in the cavity formed by combining the molds, and an end portion of the tube formed at the end of the mold. Then, the tube is covered with a stretchable base fabric, and the ends of the base fabric are also fixed via nozzles placed in the fixing part formed in the mold. Further, the base fabric is impregnated with a synthetic resin by any means, the mold is clamped, air is injected into the tube through a nozzle to expand it, and the stretchable base fabric is pressed against the wall of the mold. 1. A method for manufacturing a hollow molded article, which comprises manufacturing a hollow molded baseball glove or mitt by curing the product. 4. The tube according to claim 3, wherein the shape of the tube disposed in the cavity formed by the plurality of molds having shapes of baseball gloves and mitts is substantially similar to the shape of baseball gloves and mitts. A method for manufacturing a hollow molded body.