JPH08105480A - Shock absorbing plate - Google Patents

Abstract

PURPOSE: To provide a shock absorbing plate which is formed through composite plastic molding and constituted to be light and have excellent shock buffering ability. CONSTITUTION: A plurality of through-holes 3 are formed in a base sheet 1 made of polypropylene and a buffering plate 2 of a thermoplastic elastomer in which a plurality of blind holes 4 are formed in the same positions as those of the through-holes 3 is molded integrally with the base sheet 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shock absorbing plate used for furniture such as chairs and tables, lining of automobile doors, interior panels such as dashboards, and the like.

[0002]

2. Description of the Related Art Conventionally, regarding this type of shock absorbing plate,
An iron plate or a hard plastic molding material is used as a substrate for the main body mounting part, and a buffer plate made of elastomer such as soft plastic or rubber is adhered to it by an adhesive, or heat is applied on the substrate simultaneously with the molding of the substrate. Methods such as integrally molding a plastic elastomer to form a cushioning plate have been adopted. However, in the case of using an adhesive, the adhesive strength between the substrate and the buffer plate is weak, resulting in defective adhesion and defective products, and problems in the working environment due to the use of an organic solvent, and the adhesive in the process knitting. However, there was an unavoidable problem in production such as the need to incorporate the curing time.
Also, in the case of integral molding, in order to increase the cushioning effect, it is necessary to thicken the layer of the cushioning plate in the thermoplastic elastomer portion, which not only increases the weight of the product but also raises the cost of the product.

[0003]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention forms a shock absorbing plate by molding a composite plastic and is lightweight, has good shock absorbing properties, and is low in product cost. The purpose is to provide.

[0004]

In order to achieve the above object, the present invention provides a thermoplastic elastomer in which a plurality of through holes are formed in a polypropylene resin substrate and a plurality of blind holes are formed at the same positions as these through holes. The elastic plate is molded integrally with the substrate.

[0005]

With the above-mentioned structure, the board portion is fixed to the target device with bolts, etc., and the shock absorbing is absorbed by the layer of the buffer plate, which is provided at the same position as the plurality of through holes of the board. The blind holes in the baffle increase the flexibility of the baffle to absorb impact and enhance the overall impact cushioning properties.

[0006]

Embodiments of the present invention will be described in detail with reference to the accompanying drawings. FIG. 1 is an exploded perspective view showing the configuration of an embodiment of the present invention, in which a substrate 1 made of a hard polypropylene resin and a buffer plate 2 made of a non-vulcanized thermoplastic elastomer are formed in a state of being intimately bonded by integral molding. At this time, a plurality of through holes 3 are formed in the substrate 1, and the plurality of through holes 3 of the buffer plate 2 are formed.
A plurality of blind holes 4 are provided at the same position as.

FIG. 2 is a cross-sectional view showing a state in which the substrate 1 and the buffer plate 2 of FIG. 1 are integrally molded. The shock (indicated by arrows in the figure) applied to the buffer plate 2 is buffered by the deformation of the plurality of blind holes 4. Be absorbed. By providing a large number of blind holes 4 each having a hemispherical tip at the buffer plate 2 corresponding to the through holes 3 of the substrate 1, the weight of the buffer plate 2 is reduced to achieve weight reduction and cost reduction.
The blind hole 4 increases the flexibility of the buffer plate 2 and can absorb the applied impact force. Even if the buffer plate 2 is provided with a prismatic blind hole, the weight of the buffer plate 2 can be similarly reduced and the shock can be absorbed, but the elasticity is different between the blind hole portion of the buffer plate 2 and its periphery. Not only does it give an uncomfortable feeling when a pressure is applied to that portion, but it may deform in appearance and cause a problem. On the other hand, when the inner end of the blind hole 4 is formed into a hemispherical shape, the difference in elasticity between the blind hole 4 and the case without the blind hole 4 is small, the change in elasticity is gentle, and the feeling of strangeness is small.

FIG. 3 is a cross-sectional view of an essential part showing a state in which the embodiment of the present invention is attached to a corner ridge of a device. Comparison is made by a blind hole 4 having a hemispherical tip even against an impact applied to the corner ridge. The impact can be absorbed uniformly and the discomfort at the time of pressing can be reduced. 4 and 5 are cross-sectional views showing an example of a mold for molding an embodiment of the present invention, which is composed of a mold 5 having a double molding structure, and the cavity side mold 5a has a predetermined height from the inner bottom surface. A plurality of protruding pieces 6 each having a hemispherical tip protruding upwardly are formed, a first gate 7a is formed in the center of the bottom surface of the cavity side mold 5a, and a second gate is formed at the center tip of the plurality of protruding pieces 6.
To form the gate 7b. On the other hand, the core side mold is composed of a first core side mold 5b corresponding to molding of the substrate 1 and a second core side mold 5c used for molding of the buffer plate 2, and the first core side mold 5c. The mold 5b is fitted in the cavity-side mold 5a leaving the thickness of the substrate 1 left. The first core-side mold 5b is provided with a blind hole having a hemispherical tip with a predetermined depth at the same position as the plurality of protruding pieces 6 of the cavity-side mold 5a. The second core-side mold 5c is fitted into the cavity-side mold 5a, leaving only the thickness of the substrate 1 and the buffer plate 2.

As shown in FIG. 4, first, the first core-side mold 5b is fitted in the cavity-side mold 5a, and polypropylene resin is injection-molded from the first gate 7a to form the substrate 1. Then, as shown in FIG. 5, the first core-side mold 5
Replacing b with the second core side mold 5c, fitting it into the cavity side mold 5a, injecting thermoplastic elastomer from the second gate 7b and molding it integrally with the polypropylene resin substrate 1 to absorb shock. Form a plate.

[0010]

As described above, according to the present invention, when a shock absorbing plate is formed by integrally molding a shock absorbing plate on a substrate made of a hard polypropylene resin with a soft thermoplastic elastomer,
By forming a plurality of blind holes in the cushion plate through the substrate, it is possible to increase the flexibility of the cushion plate to improve the shock cushioning property, and reduce the material usage amount to save the material cost.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing a configuration of an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a state where the substrate 1 and the buffer plate 2 of FIG. 1 are integrally molded.

FIG. 3 is a cross-sectional view of essential parts showing a state in which an embodiment of the present invention is attached to a corner ridge of a device.

FIG. 4 is a cross-sectional view of a mold for molding an example of the present invention.

FIG. 5 is a cross-sectional view of a mold for molding an example of the present invention.

[Explanation of symbols]

 1 substrate 2 buffer plate 3 through hole 4 blind hole 5 mold 5a cavity side mold 5b first core side mold 5c second core side mold 6 projecting piece 7a first gate 7b second gate

Claims (1)

[Claims] 1. An elastic plate of a thermoplastic elastomer in which a plurality of through holes are formed in a hard substrate made of polypropylene resin and a plurality of blind holes are formed at the same positions as these through holes are integrally formed on the substrate. A shock absorbing plate.