JPS5848190B2 - Skis with core material made of foamable resin with inner grooves and method for manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a ski with a foamable resin core and a method for manufacturing the same, and more particularly to a ski optimal for cross-country skiing and a method for manufacturing the same.

Cross-country skis must be lightweight to allow for long-distance running, even if it means sacrificing some strength.

In order to meet this demand, there have conventionally been skis in which the interior of skis has been hollowed out to reduce weight, but this has the drawback of being complicated and expensive to manufacture.

In order to overcome this drawback, there are skis in the past that have a resin material sandwiched between the upper and lower drawing boards.In this case, in order to take advantage of the screws used to fix fasteners etc. An auxiliary plate is fixed to the underside of the upper plate.

However, according to this method, the auxiliary plate must be made quite thick in order to make full use of the screws, which has the disadvantage of defeating the purpose of reducing weight.

The present invention eliminates all of these conventional drawbacks.
The purpose of this ski is to provide a ski that is especially suitable for cross-country skiing, and its characteristics include the use of foamed resin as the core material to reduce weight, and the use of a foamed resin inside the core material to make use of screws. By providing the interpolated plate at a slight distance from the plate, weight reduction is not compromised.

Hereinafter, preferred embodiments of the present invention will be described in detail based on the accompanying drawings.

In FIGS. 1 and 2, 1 is a ski, and this ski 1 has an upper ski 2, a lower ski 3 facing the upper ski 2 at a predetermined distance, and both upper and lower skis 2, 3. It is comprised of a core material 4 made of a foamed resin, such as a foamed urethane resin, sandwiched between them, and an insert plate 5 made of a synthetic resin embedded in the core material 4.

Note that 6 is a sliding surface material fixed to the lower surface of the lower plate 3.

The insertion plate 5 corresponds to a substantially central portion in the longitudinal direction of the upper plate 2, which is a position where a screw (not shown) is screwed into the upper plate 2 in order to fix a fastener (not shown) or the like to the upper plate 2. In addition, the upper plate 2 is embedded in the core material 4 so as to be positioned at a slight distance from which the tips of the screws can penetrate.

As is clear from FIG. 3, the insert plate 5 has a large number of through holes 7 in the thickness direction, and protrusions 8 protruding in the width direction at equal intervals on both sides. A few have been formed.

The tip surfaces of these protrusions 8 and the side surfaces of the ski 1 are aligned.

Further, the density of the core material 4 between the upper plate 2 and the insert plate 5 is higher than the density between the lower plate 3 and the insert plate 5.

Next, the manufacturing method of this example will be explained.

First, the lower plate 3 is placed at the bottom of the lower mold 9 of an injection molding machine (not shown), and supported by the inner wall surface of the lower mold 9, and the insert plate 5 is placed in the lower mold 9. The upper plate 2 is supported by the lower mold 9 at a predetermined position in the longitudinal direction and the height direction so that each protrusion 8 comes into elastic contact with the inner wall surface of the lower mold 9. It is placed at the top and supported by the inner wall surface of the lower mold 9 with pressure.

After the upper plate 2, insert plate 5, and lower plate 3 have been installed in the lower mold 9, urethane resin, which is the material of the core material 4, is added to the injection molding machine in the same way as in normal injection molding work. After the upper mold 10 and the lower mold 9 are closed by mold clamping, the material is injected into the gap between the upper plate 2 and the lower plate 3.

At this time, the injected material passes through the through hole 7 of the insert plate 5 and also passes through the gap between both sides of the insert plate 50 formed by the protrusion 8 and the inner wall surface of the lower mold 9. The narrow gap between the upper plate 2 and the insert plate 5 is evenly filled.

Then, the material that filled the narrow gap between the upper plate 2 and the insert plate 5 comes into contact with the insert plate 5 when passing through the through hole 7 and the side part, thereby absorbing heat and lowering the temperature. As a result, foaming is suppressed more than in other parts, resulting in a higher density.

Therefore, this density increases in proportion to the heat absorbability of the material of the interpolation plate 5.

After the material has been injected, the shaped ski 1 can be taken out of the mold using the same procedure as in normal injection molding operations.

In this way, according to the present invention, since the interpolation board is provided at a location slightly separated from the top board, the screws can be supported at two points, and the support is strong, and the core material between the drawing boards Since the density of the inner plate is higher than that of other parts, the above-mentioned support can be provided more firmly.In addition, by providing a through hole in the inner plate, weight reduction is promoted and the connection between the inner plate and the upper plate is improved. Narrow gaps can be filled more evenly, the foamed resin is bridged through through holes, making it strong against the curvature of the ski, and it is extremely easy to manufacture. It is something that can be effective.

It goes without saying that the present invention is not limited to the above-described embodiments; for example, the material of the insert plate may be metal in addition to synthetic resin, and the protrusion is not necessarily necessary. If not, you can support the through-hole part of the insert plate with a pointed member and install it inside the mold.
It goes without saying that many modifications may be made without departing from the spirit of the invention.

[Brief explanation of the drawing]

The drawings show a preferred embodiment of the present invention, in which Fig. 1 is a schematic side view of the entire ski showing the arrangement position of the interpolation plate, Fig. 2 is a sectional view of the ski, and Fig. 3 is the interpolation plate. Partial plan view of the plate, No. 4
The figure is a partial sectional view showing a state in which each member is placed in a mold. 1... skis, 2... upper skis, 3...
...Lower plate, 4... Core material, 5... Insertion plate, 6... Sliding surface material, 7... Through hole,
8...Protrusion, 9...Lower mold, 10...
...Top mold.

Claims (1)

[Scope of Claims] 1. An upper plate and a lower plate are positioned opposite to each other with a core material made of foamed resin sandwiched therebetween, and a fastening fitting or the like is fixed to the upper plate within the core material made of foamed resin. In order to support the screws at two points with the upper plate, the screws should be supported at two points on the lower plate so that they correspond to the positions where the screws are screwed together and there is a slight gap between the upper plate and the tip of the screw. 1. A ski board made of foamable resin as a core material and having an insert board embedded at an eccentric position in the direction of the upper board. 2. A screw for fixing a fastening fitting, etc. to the upper plate is installed in the core material made of foamed resin of a ski in which the upper plate and the lower plate are located opposite to each other with a core made of foamed resin sandwiched between them. In order to support the upper plate at two points, the upper plate is offset in the upper plate direction with respect to the lower plate so that it corresponds to the position where the screws are screwed together, and there is a slight gap between the upper plate and the screw tip. 1. A ski board made of foamed resin as a core material and having an insert board which is located and buried and is configured to have a large number of through holes extending in the thickness direction. interpolation board. 3. An upper plate and a lower plate are supported in a mold of an injection molding machine so as to be positioned facing each other at a predetermined interval, and screws for fixing fastening fittings etc. to the upper plate are installed between the drawing plates. In order to support the plate at two points, it corresponds to the position where the screws are screwed together, and the upper plate is offset in the direction of the upper plate with respect to the lower plate so that there is a slight gap in which the tip of the screw can penetrate. Manufacture of a ski board made of foamable resin as a core material and having an insert plate that is positioned to support the insert plate and inject foamable resin into the gap between the upper plate and the lower plate. Method.