JPH045472B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Field of Application) The present invention relates to a method for manufacturing an injection key. (Conventional technology and its problems) In recent years, new materials such as glass fiber and carbon fiber have been incorporated into the structural materials of skis, and the performance of skis has improved dramatically, and manufacturing methods and technology have improved accordingly. Things are changing. In particular, foamable resins such as urethane foam have been developed as core materials for skis, and in-jet skis in which these foamable resins are injected have appeared. By the way, conventional skis using the above-mentioned new materials have a multi-layered structure, and the upper surface thereof is formed flat. The structure in which the upper surface is made flat in this manner is advantageous in manufacturing when a multilayer structure is adopted as described above, and is also considered to be sufficient in terms of strength. However, in competition skis or skis for advanced skiers, there is a demand for skis that are superior in rotational maneuverability, high-speed stability, and edgeability.
However, the characteristics of a ski are largely dependent on the overall shape of the ski, and if you only use a ski with a flat top surface as described above, you will have no choice but to adjust the internal structure, side curves, etc. The problem is that the degree of freedom is limited. The present invention breaks through the conventional common sense as described above, and provides an in-edge extension ski that increases the degree of freedom in ski design by providing a chevron or a large portion on the upper surface of the ski, and further improves the various characteristics of the ski. A manufacturing method is provided. The chevron-shaped protrusions on the upper surface of the ski are typical of early wooden veneer skis. However, in the above-mentioned wooden veneer ski, the chevron-shaped protrusion is simply provided to increase the breaking strength, and the chevron-shaped protrusion can be formed extremely easily by simply cutting out the wooden board. It is extremely difficult to apply such a chevron-shaped protrusion to a ski with a multilayer structure using the above-mentioned new material. For example, it is conceivable to form a chevron-shaped protrusion by laminating wood chips or the like to the upper surface of a conventional ski that has a flat upper surface, but this would make the manufacturing process extremely complicated and inevitably increase costs. Furthermore, if wood chips or the like are pasted together, there is a risk that the wood chips may peel off if twisting stress is concentrated. (Summary of the Invention) The present invention was achieved for the first time as a result of intensive studies based on the above circumstances.The purpose is to improve the bending elasticity by increasing the degree of freedom in the design of skis. , the effects of in-jexion skis that can improve various properties, such as excellent torsional elasticity breaking strength, particularly small moment of inertia, excellent operability, good vibration damping properties, and excellent high-speed stability. The aim is to provide a manufacturing method that is In addition, the feature is that the ski lower surface component is placed in the lower mold of the mold, the ski upper surface component is placed bridging between the upper surfaces of both side walls of the lower mold, and placed on the lower mold at a desired position on the inner upper surface. An upper mold having a concave portion in a desired shape is assembled from above the ski upper surface component, and a foamable resin is injected and filled into the space between the ski upper and lower surface components arranged in the mold, and the foaming resin is heated to a foaming pressure. In the method for manufacturing an injection ski, the ski upper and lower surface components are brought into pressure contact with the inner upper surface of the upper mold, and the ski upper surface component is deformed to follow a recess formed in the inner upper surface of the upper mold. When disposing the ski top surface component on top of the upper mold, the ski top surface component is assembled later with the central portion supported by both edges of the ski top surface component between the protrusions provided on the upper surface of both side walls of the lower mold. It is characterized by being bent upward so as to protrude halfway up the recess. Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. 1 and 2 are side views of an injection ski 10 manufactured by the method of the present invention, respectively;
A plan view is shown. FIG. 3 is a sectional view taken along the - line in FIG. 1. For the sake of simplicity, the drawings are shown with bends omitted so that the upper surface of the conventional ski is flat, and the thickness of the conventional ski is made uniform (the same applies to the following examples). In Figure 3, 11 is an ABS resin sheet,
12 is a lower surface reinforcing material, 13 is a side surface reinforcing material, and 14 is a sole material provided under the lower surface reinforcing material 12, and the ski stand frame body is hollow as a whole. 1
5 is an edge metal fitting with a bottom reinforcement material 12 and a side reinforcement material 1
It is inserted and fixed between 3 and 3. Reference numeral 16 is a foamable resin such as urethane foam, which is injected and solidified into the ski frame as a core material. Reference numeral 17 denotes an internal reinforcing material made of glass cloth or the like, which is fixed in contact with the inner surface of the ski frame frame by means of a foamed resin 16. The characteristic feature of this embodiment is that the ski 10
The upper surface is formed flat over the area where the fasteners are attached to the central thickness of the ski base frame, and the height gradually decreases from this central thickness toward the top and tail of the ski. The protrusion has a chevron-shaped cross section in the width direction except for the area where the fastener is attached. As is clear from FIG. 3, the structure of the protrusion at this point is such that the ABS resin sheet 11 serving as the top surface material is bent to form a chevron-shaped cross section, and an internal reinforcing material 17 such as glass cloth is attached to the ABS resin sheet 11. They are bent so as to be in close contact with each other, and a foamable resin 16 such as urethane foam is formed by integrally filling the above-mentioned bending space. The dimensions are illustrated using a ski with a length of 180 cm as an example (Figures 1 and 2). The thickness of the protrusion is relative to the curve of the upper surface of a conventional ski. In Figures 1 and 2, the length of the fastener installation range A in the center of the ski stand frame is approx.
It is 55cm long and approximately 5mm thick. Moreover, the surface is flat. Note that the edge portion may be slightly rounded. The top side part B and tail side part C of the ski adjacent to the above range A are approximately 9 cm in length.
The height decreases toward the tip, down to 2.5 mm. Further, the thickness of the range D adjacent to the range B above is maintained at 2.5 mm over a length of 34 cm, and the range E adjacent to the range C above is maintained at a thickness of 2.5 mm over a length of 25 cm.
In ranges F and G adjacent to , the height gradually decreases from 2.5 mm to 0 over a length of 9 cm. As shown in Figure 2, the width of the protrusion is
Ranges D, E, F, and G are narrower than the width of the ski. Further, in the range G, the protrusion may be bifurcated as shown in FIG. When the protrusion is bifurcated in this manner, the torsional elasticity of the tail portion is strengthened. Note that the shape of the protrusion is not limited to the above, and as shown in Figure 5, it may be formed so that it becomes lower continuously from the fastener attachment area in the center of the ski frame body toward the top and tail of the ski. It's okay. Alternatively, ranges A to E may be made to have the same height as shown in FIG. In the present invention, the formation of the protrusions described above causes the mass distribution of the ski to be biased toward the center of gravity. Other embodiments are shown in FIGS. 8, 9, and 10, respectively. These three side projection shapes, as shown in FIG. 7, are the same as those shown in FIG. 1. Alternatively, it may be as shown in FIG. 5 or 6, in which the upper surface of the ski is formed in the shape of a high platform at the center in the longitudinal direction. That is, the ski has an inflection surface that changes from an upwardly concave portion X to an upwardly convex portion Y near the top and tail portions of the ski. Among the above-mentioned side projection shapes, those shown in FIGS. 8 to 9 are examples showing the respective negative cross-sectional forms in FIG. 7. FIG. 8 shows that the protrusion is formed completely in the width direction of the ski,
The top surface is flat. In this embodiment as well, the swing weight is light and the operability of the ski is improved. In the one shown in FIG. 9, the protrusion is formed in a chevron shape with two tops. In this embodiment, the breaking strength of the ski is further increased. In the ski shown in FIG. 10, the protrusion is formed completely in the width direction of the ski, and the upper surface is formed into a concave surface. In this embodiment, it is possible to prevent scratches on the upper surface of the ski due to crossing of the left and right skis. 8th
In the case shown in FIGS. 9 to 9, the upper surface of the fastener attachment area is also formed flat. FIGS. 11 and 12 show still other embodiments. In this embodiment, as is clear from the end face portion of FIG. 12, the upper surface of the ski is deformed into an upwardly convex mountain shape in the cross-sectional form in the width direction. The side projection shape may be any shape. As in this embodiment and the embodiments shown in FIGS. 3 and 9, when the ski is constructed so that the mass is concentrated at the center in the width direction, the swing weight centered on the longitudinal center line of the ski becomes lighter and improves the ease of edging cornering. Next, the manufacturing method according to the present invention will be explained based on FIG. 13. First, the sole material 14, lower surface reinforcing material 12, edge fittings 15, and side reinforcing material 13 are set at predetermined positions in the lower die 20 of the roll. Next, an inner reinforcing material 17, such as a glass cloth bent into a U-shaped cross section, is inserted into each set space from the open upper surface. Next, the upper surface portion 17' of the inner reinforcing material 17 and the ABS resin sheet 11 are laminated to cover the open surface of the lower mold 20, and the four pins 21 (however, the two (Only a book is shown in the figure) is held between the protrusions of a book by bending it upward so that it is convex. Then, an upper mold 22 whose inner upper surface is formed into a concave shape having the desired protrusion shape is fitted from above to complete the setting. In this case, the top member 1
7', the ski upper surface component (upper surface material) made of ABS resin sheet 11 etc. is supported on both sides between the pins 21, and is bent upward so that the center part protrudes to the middle of the concave surface of the upper mold 22. . Next, while uniformly pressurizing the upper surface of the upper mold 22 with an air bag (not shown) or the like, a foamable resin such as urethane foam is injected into the mold and solidified. However, due to the heat generated during foaming of the foamable resin, the ABS resin sheet 11
At the same time, the foaming pressure causes the flexible upper member 17' of the internal reinforcing material and the ABS resin sheet 11 to be concavely pressed against the inner upper surface of the upper mold 22, forming the upper surface of the ski in the desired shape. A ribbed structure can be obtained. As mentioned above, the ski upper surface component is bent upward in advance so as to protrude halfway into the concave surface (recess) of the upper die 22.
The upper mold 22 is moved smoothly due to the foaming pressure of the foamable resin.
It is even pressed against the concave surface of the surface. After molding, the upper surface member 17' and the ABS resin sheet 11 generate burrs, so these are removed by polishing, and if necessary, the upper surface of the ski is painted or printed to complete the ski. As the top material, in addition to the combination of the ABS resin sheet 11 and the internal reinforcing material 17 such as glass cloth as described above, the ABS resin sheet alone may be used, or as shown in FIG. 14, an ABS resin sheet with recesses may be used. 11 and a glass cloth 23 provided so as to fit into this recess, or as shown in FIG.
As shown in the figure, even if the ABS resin sheet 11, aluminum top edge 24, glass cloth 23, and rubber sheet 25 are combined, the foaming pressure of the foamable resin causes each of the above-mentioned top materials to move inside the upper mold 22. It was confirmed that the desired protrusion structure could be obtained by closely adhering to the concave surface of the upper surface. Further, the ABS resin sheet 11 can be replaced with an epoxy resin sheet. Further, as an internal reinforcing material, as shown in FIG. 17, a glass fiber tape 26 vertically impregnated with epoxy resin or the like and formed into a tape shape of a predetermined width is used.
A structure in which the wires are arranged in parallel at regular intervals, a nylon thread 27 is sandwiched between them, and a wire 28 is laterally braided can also be preferably used. This part reinforcement material 2
No. 9 has large mesh openings, so the foamed resin enters the gaps and bridges, making it more firmly fixed. In addition to being able to be fixed tightly to the inner surface of the ski frame frame as described above, this internal reinforcing material 29 can also be formed by foaming by appropriately bending braided wire as shown in FIG. This has the effect of further increasing the degree of freedom in designing the strength of the resin. The foamable resin injection conditions described above allow the upper material to be brought into close contact with the concave surface of the upper mold 22 by the foaming pressure without changing the conventional conditions, that is, without particularly increasing the foaming ratio. In normal skis, it is considered that the density ρ (average density in the ski frame frame) of the foamable resin after foaming is about 0.6, which is good in terms of the ski's breaking strength. In the present invention, a free blow of about 0.1 (expansion ratio of about 10 times) is used to
The foaming pressure obtained by the injection amount of approximately 0.6 allows the upper surface material to be brought into sufficient contact with the concave surface of the upper mold 22. In addition, as a result of the experiment, the free blow was 0.1
The upper material could be brought into close contact with the concave surface of the upper mold 22 even with a foaming pressure of approximately 0.4, using a foaming resin of approximately 100% and an injection amount of approximately ρ = 0.4. In this case, the ski strength will be somewhat lower, so the strength can be supplemented by using the above-mentioned braided internal reinforcing material. Furthermore, it was possible to deform the top material even with a low foaming ratio of about 0.2 for free blow. Since the ski produced by the method of the present invention is an in-jet ski that uses a foamable resin, the foamable resin in the area near the inner surface of the ski base frame is a dense skin with a suppressed foaming rate, as usual. layer 3
0 (Fig. 3), and this skin layer 30 is formed in a protrusion structure such as a chevron-shaped rib along the upper surface material on the upper surface side of the ski, so that the ski Overall strength increases. In addition, the vibration of skis when skiing is largely absorbed by foamed resin, but as mentioned above, the foamed resin itself has a protruding structure such as chevron ribs on the upper side, so the vibration damping properties of skis are extremely high. This results in better high-speed stability. Furthermore, since the upper surface of the ski is formed into a trapezoidal shape that rises toward the center in the longitudinal direction of the ski, the mass of the ski is concentrated closer to the center of gravity, reducing the moment of inertia and greatly improving the operability of the ski. There are many differences in skis depending on the fairness of the material, etc., but if the width is constant, the bending stiffness and torsional stiffness are approximately proportional to the cube of the thickness, and the bending strength and torsional strength are also proportional to the thickness. There is a relationship that is approximately proportional to the square of . In order to create a ski with the necessary strength and rigidity while maintaining a constant width of the running surface and appropriate side curves, it is most logical to have a trapezoidal or semi-cylindrical cross section. In particular, since the shear stress of bending follows an arcuate plane centered on the bending center, it is optimal that the cross-sectional shape of the upper surface of the ski be an arcuate shape as shown in FIG. In the present invention, by using the foaming pressure of the foamable resin, the strength members placed on the surface layer can be deformed into an arcuate shape without waste, so a light ski with the necessary strength and rigidity can be efficiently manufactured. can do. Furthermore, compared to conventional skis, it is now possible to freely select the distribution of bending and torsional stiffness, making it possible to provide skis that are most suitable for various performance requirements. In other words, for example: (1) With the same performance, you can ski lighter (with a smaller moment of inertia) and easier to handle. (2) Because it has a moderate amount of flexibility, the pressure distribution on the contact surface is evenly spread out, making it possible to create skis with good glide stability and ease of carving turns. (3) By increasing the maximum thickness of the cross section, the ski has good damping while maintaining a slim shape (taking advantage of the vibration damping properties of the material). The characteristics of the ski are shown below.

[Table] The prototype is shown in Figure 19, and the prototype 2 is the one shown in Figure 19.
According to what is shown in Figure 0. (Effects of the Invention) As described above, according to the method of the present invention, the central part of the ski upper surface component between the protrusions provided on the upper surface of both side walls of the lower mold protrudes halfway into the recess of the upper mold to be assembled later. Since the upper mold is assembled from above by bending it upward and deforming it in advance, the upper mold is assembled from above, so that the foaming pressure of the foamable resin moves the ski upper surface component to the inner upper surface of the upper mold of the mold. It can be smoothly projected into the recess of the recess, and even if the recess is relatively deep, it can be easily brought into close contact with the recess surface. Therefore, it is possible to have a protrusion on the top surface without adhering or cutting out the chip.
Moreover, an integral ski with a continuous upper surface component can be manufactured easily and at low cost. Therefore, the degree of freedom in ski design is increased, and skis with excellent properties can be provided.

[Brief explanation of drawings]

Fig. 1 is an explanatory side view of the injection ski according to the present invention, Fig. 2 is an explanatory plan view, Fig. 3 is a cross-sectional view of Fig. 1, and Fig. 4 is another embodiment of the rib shape near the tail. FIG. 3 is a plan view showing an example. Figure 5,
FIG. 6 is an explanatory side view showing other embodiments of the rib shape. FIG. 7 is a side projection view showing another embodiment, and FIGS. 8 to 10 are end views thereof. FIG. 11 is a side projection view showing still another embodiment, and FIG. 12 is an end view thereof. FIG. 13 is a sectional view of the mold. Figures 14 to 16 are explanatory sectional views showing other examples of the top surface material, Figure 17 is an explanatory view showing other examples of the internal reinforcing material, and Figure 18 is an explanatory view showing other examples of the internal reinforcing material. A cross-sectional view of the ski is shown. FIGS. 19 and 20 show plan views of skis used for characteristic tests. 10... Indjiexionsky, 11...
ABS resin sheet, 12... Bottom reinforcement material, 13...
... Side reinforcement material, 14 ... Sole material, 15 ... Edge metal fittings, 16 ... Foamed resin, 17 ... Internal reinforcement material, 17' ... Top member, 20 ... Lower mold, 21 ...
... Pin, 22 ... Upper mold, 23 ... Glass cloth, 24
...Aluminum top wedge, 25...Rubber sheet,
26...Glass fiber tape, 27...Nylon thread, 28...Wire, 29...Internal reinforcing material, 3
0...Skin layer.

Claims (1)

[Scope of Claims] 1. A ski lower surface constituent member is arranged in the lower mold of a mold, a ski upper surface constituent member is arranged bridging between the upper surfaces of both side walls of the lower mold, and a desired inner upper surface is placed on the lower mold. An upper mold with a recess in a desired shape is assembled from above the ski upper surface component, and a foamable resin is injected and filled into the space between the ski upper and lower surface components arranged in the mold. In the method for manufacturing an in-jet excision ski, the ski upper surface component is brought into contact with the inner upper surface of the upper mold by foaming pressure, and the ski upper surface component is deformed to follow the recess formed in the inner upper surface of the upper mold. When disposing the ski top surface component on the mold, the two edges of the ski top surface component are supported between the protrusions provided on the upper surface of both side walls of the lower mold, and the center part of the ski top surface component is assembled later. A method for manufacturing an in-die extension ski, characterized in that the ski is bent upward so as to protrude halfway into the recess of the mold.