JPH0512014Y2 - - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to an injection foam molding device for a hollow shell body having a receiving recess such as a socket on the surface, such as a plastic hull of a small ship.
The present invention relates to the structure of a jig that presses the surface of a hollow shell against foaming pressure in the molding apparatus.

[Conventional technology]

Some small vessels used for leisure purposes in coastal waters have a hull made of a hollow shell with a molded plastic deck and hull joined together.

This type of hull structure has a receiving recess on the deck surface (upper surface) for passengers to board, and the hollow area around the receiving recess is filled with a resin foam such as polyurethane to increase buoyancy. Additionally, structures that provide hull strength have been proposed, for example, for small lifeboats.

In addition, as a method for filling the inside of a hollow shell with a resin foam, by injecting a resin and a foaming agent into the hollow shell and directly foaming it inside,
A method is used in which molding (filling) and adhesion are performed simultaneously.

In injection foam molding of such a hollow shell, it is necessary to press the surface of the hollow shell with a jig of the same shape in order to prevent deformation due to internal pressure during foaming, and injection foam molding equipment for this purpose is required. is used.

This injection foam molding apparatus is generally comprised of two presser jigs, upper and lower (same for left and right) that face each other at mating surfaces. As prior art, the applicant's patent application
There is No. 62-250863.

[Technical problem that the invention attempts to solve]

However, in the conventional injection foam molding apparatus for hollow shells of the above-mentioned type, when a hollow shell having a receiving recess on the surface is injected and foamed, for example, as seen in small plastic boat hulls, the above-mentioned The wall thickness of the hollow shell is thin, and the draft angle of the mold of the receiving recess is small in order to secure the accommodation space (for example,
(approximately 3.5 degrees), even if an attempt was made to pull out the presser jig from the receiving recess after foaming was completed, it was sometimes difficult to remove the jig due to the frictional force caused by the foaming pressure.

The present invention was developed in view of the above-mentioned conventional technical problems, and when foaming a hollow shell having a receiving recess, the draft angle of the mold of the receiving recess is small, and the foaming jig is attached to the holding jig. It is an object of the present invention to provide an injection foam molding device for a hollow shell body, in which the holding jig can be easily removed after foaming even when pressure is applied.

[Means for solving problems]

The present invention provides an injection foam molding apparatus that presses the surface of a hollow shell against foaming pressure during injection foaming of a hollow shell having a receiving recess on the surface. It is composed of a movable jig that presses the surface of the movable jig and a fixed jig that presses the opposite surface, and the part of the movable jig that fits into the receiving recess is aligned along the tapered surface of the wedge part provided on the movable jig. By being composed of a plurality of movably attached blocks, even when the hollow shell is in pressure contact with the surface pressing means due to the foaming pressure, the movable jig can be easily separated from the receiving recess, and the foaming The present invention provides an injection foam molding device that can improve the workability of the process.

〔Example〕

The present invention will be explained in detail below with reference to the drawings.

FIG. 6 is a perspective view illustrating the hull of a small watercraft, which is a hollow shell suitable for injection foaming with the apparatus according to the present invention, and FIG. 7 is a cross-sectional view of FIG. 6.

In FIGS. 6 and 7, the illustrated hull 10
is deck 1, which is a plastic molded product such as FRP.
1 and a hull 12 joined together, and a resin foam 13 such as urethane foam is placed inside the shell.
is filled.

A receiving recess 14 as a cockpit is formed on the upper surface of the deck 11, and the inside thereof is equipped with operating devices such as an engine 15 and a steering wheel 16, a seat 17, a fuel tank 18, etc., and a driver 19.
The person is seated on the seat 17 and gets on the boat while holding the handlebar 16.

The resin foam 13 filled in the hull 10 is for ensuring buoyancy and hull strength.

Such a small boat is about 3.5 m long and about 1.7 m wide.

The thickness of the hollow shell constituting the hull 10 is, for example, selected to be 1.2 to 1.8 mm in the thin portion of the deck 11, and approximately 3 mm in the hull 12.

FIG. 1 is an exploded perspective view of an embodiment of the injection foam molding device for hollow shells according to the present invention, and FIGS. 2 and 3 show the surface of the hollow shell being pressed down by the device shown in FIG. 1 during foaming. FIG. 4 and FIG. 5 are a cross-sectional view and a vertical cross-sectional view when the presser jig is lifted after foaming in the apparatus of FIG. 1.

In FIGS. 1 to 5, the injection foam molding apparatus shown in FIG. an upper movable jig 20 that is a pressing jig and presses the surface of the deck 11 including the receiving recess 14;
It is comprised of a lower fixing jig 21 that presses the opposite surface (the surface of the hull 12 in the illustrated example).

The fixing jig 21 is provided with a concave curved surface 22 that matches the shape of the hull 12 of the hull 10.

On the other hand, the movable jig 20 presses down the receiving recess 14 and its surrounding area 23, and the surface (concave surface) of the receiving recess 14 is formed by a plurality of aggregate blocks 27 attached to the holding plate 28 of the movable jig 20. The outer peripheral surface of the peripheral portion 23 is pressed by an inner surface of the same shape formed on the pressing plate 28.

That is, the upper movable jig 20 includes a presser plate 28 that is attached to a press or a hoist (not shown) and moves up and down, and a bolt on the lower surface of the presser plate 28.
The wedge member 25 is fixed with a nut or the like, and a plurality of blocks 27 are movably suspended from the presser plate 28 by wires, chains, ropes, etc. along the tapered surface 26 of the wedge part 25. , the peripheral part 23 of the deck 11 is connected to the presser plate 2.
The receiving recess 14 of the deck 11 is directly pressed by the inner surface of the holding plate 2.
It is held down by a plurality of blocks 27 of a set-separate type that are movable along a wedge part 25 (a cross-shaped wedge part in the illustrated example) provided at 8.

In the illustrated example, four blocks 27 aligned with each corner of the cross-shaped wedge portion 25 are suspended from the holding plate 28, and are fitted into the socket 14 to press down the holding plate 28. In the pressed state, the four blocks 27 are configured so that their peripheral surfaces and lower surfaces come into contact with almost the entire surface of the cockpit 14.

In the illustrated example, each block 27 has a flexible member 2 such as a wire, chain, or rope of a predetermined length (for example, about 10 cm) on the lower side of the presser plate 28.
It is suspended at 9.

Injection foaming into the hollow shell 10 is performed in the following steps.

With the movable jig 20 pulled up or removed, the deck 1 made of plastic such as FRP
The hollow hull (hollow shell) 10 formed by joining 1 and the hull 12 is fixed to the concave curved surface 22 of the fixing jig 21.
position it inside and set it.

Therefore, the movable jig 20 is lowered from above with respect to the hollow shell 10, and each block 27 is inserted into the cockpit 14 while being guided by a predetermined tapered surface 26 of the wedge portion 25.

When the movable jig 20 is lowered to the predetermined position shown in FIG. 2 and FIG. Then,
A presser surface is formed that coincides with substantially the entire surface of the hollow shell 10.

An injection port 3 is provided at an appropriate position in the hollow shell 10.
0.30 (FIG. 1) is formed, and a kneading agent of a synthetic resin and a blowing agent is injected through the injection port 30.

In this case, the inside of the hollow shell 10 is
It is preferable to divide the solution into front and rear spaces (FIGS. 3 and 5) and inject separately into each of the front and rear spaces from two injection ports 30, 30.

The injected kneading agent starts foaming inside the hollow shell 10, and eventually the hollow shell 10 is filled with the resin foam without any gaps, and foaming pressure (internal pressure) acts on the hollow shell 10.

Due to this foaming pressure, the hollow shell (hull) 10 is
Although the foam tends to expand overall or locally, the surface shape is regulated by the pressing surfaces of the movable jig 20 and the fixed jig 21, so expansion and deformation is prevented, and the foam maintains its predetermined shape. The resin 13 is sufficiently filled.

When polyurethane etc. are used as foam resin,
In addition to self-foaming properties, it has self-adhesive properties, so
The foam 13 is filled with the inner surface of the hollow shell 10 in a bonded state, and when implemented in the hull 10, it is effective in increasing the buoyancy and improving the strength of the hull.

When foaming is completed, the movable mold 20 is lifted up and separated from the hollow shell 10, as shown in Figs.

According to the embodiment described above, even when the draft angle of the mold in the receiving recess 14 is small from the viewpoint of securing the stock pit volume, the presser jig pushed into the receiving recess 14 can hold a plurality of blocks supported by the tapered surface 26. 27, even if the foaming pressure is high and the contact surface pressure is high, the presser plate 28
When lifting each block 2, each tapered surface 26
7, each block 2
7 can be easily set free.

Therefore, even if the draft of the receiving recess 14 is small and the wall thickness of the receiving recess 14 is thin and easily expands and deforms under the foaming pressure, the presser jig 20 can be easily separated after foaming. , it has become possible to improve workability and reduce man-hours.

In the illustrated embodiment, the present invention is applied to a plastic hull 10, but the present invention can also be applied to a hull if injection foaming is performed on a hollow shell having a receiving recess on the surface. Not limited to,
Widely applicable.

Further, the material of the hollow shell is not limited to plastic, and hollow shells made of metal such as steel or aluminum are also applicable.

Furthermore, the number of blocks 27 that press down on the surface of the receiving recess 14 is four in the illustrated example, but it can also be divided into an appropriate number depending on the case, and any number of blocks 27 can be used as long as it is two or more. It can be carried out in a number of cases.

[Effect of idea]

As is clear from the above description, according to the present invention, in an injection foam molding apparatus that presses the surface of a hollow shell against foaming pressure when injection foaming a hollow shell having a receiving recess on the surface, The pressing means is composed of a movable jig that presses the surface including the receiving recess, and a fixed jig that presses the opposite surface,
A portion of the movable jig that fits into the receiving recess,
Since it is composed of a plurality of blocks movably attached to the tapered surface of the wedge portion provided on the movable jig, the draft angle of the receiving recess is small when a hollow shell having a receiving recess is injected and foamed. In addition, even if the pressing force of the receiving recess against the holding jig due to foaming pressure is large, the holding jig can be easily removed after foaming, and the hollow shell body can improve workability and reduce man-hours for injection foaming. An injection foam molding device is obtained.

[Brief explanation of drawings]

FIG. 1 is a schematic exploded perspective view of a hollow shell injection foam molding apparatus according to an embodiment of the present invention, and FIGS. 2 and 3 are cross-sectional views schematically showing the state of the apparatus shown in FIG. 1 during foaming. 4 and 5 are a cross-sectional view and a vertical cross-sectional view schematically showing a state in which the movable jig of the apparatus of FIG. 1 is lifted after foaming,
FIG. 6 is a schematic perspective view illustrating a hollow shell (small hollow hull) suitable for injection foaming with the apparatus of the present invention, and FIG. 7 is a cross-sectional view of FIG. 6. 10...Hollow shell (hull), 13...Foam,
14... Receiving recess (cottle pit), 20... Movable jig, 21... Fixed jig, 25... Wedge part,
26...Tapered surface, 27...Block, 28...
Holding plate, 29...hanging means.

Claims (1)

[Scope of utility model registration request] In an injection foam molding apparatus that presses the surface of the hollow shell against foaming pressure during injection foaming of a hollow shell having a receiving recess on the surface, the surface pressing means is a movable jig that presses the surface including the receiving recess. It consists of a tool and a fixing jig that presses the opposite surface.
A portion of the movable jig that fits into the receiving recess,
A hollow shell injection foam molding device comprising a plurality of blocks movably attached to the tapered surface of a wedge portion provided on the movable jig.