KR20160028211A

KR20160028211A - rotational molding equipment and methods of plastic hull with reinforcement

Info

Publication number: KR20160028211A
Application number: KR1020140116992A
Authority: KR
Inventors: 윤건구
Original assignee: 윤건구
Priority date: 2014-09-03
Filing date: 2014-09-03
Publication date: 2016-03-11

Abstract

The present invention relates to a rotational molding apparatus and a method of a plastic hull of a small boat with a reinforcement, reinforcing strength of the bottom of the hull by integrally embedding a reinforcing frame and, more specifically, to a rotational molding apparatus having a reinforcing wing vertically and horizontally formed, and having the end fixed on an outer mold by a fixing means for rotational molding, while the reinforcement having the end coated with a molten raw material powder and fixed on the hull is installed inside the mold, in a process of putting the raw material powder inside the mold, heating and rotating to form the hull.

Description

[0001] DESCRIPTION OF RELATED ART [0002] Rotating molding equipment and methods of plastic hull with reinforcement [0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus and a method for forming a small boat plastic hull using rotational molding and, more particularly, to a compact boat plastic hull form molding apparatus having a reinforcing frame, And methods.

Demand for small boats is on the rise as more watersports and leisure activities using small boats such as leisure leisure boats are on the rise.

Conventionally, these small boat hulls are made of FRP or aluminum. However, they have a high strength, but they have a high manufacturing cost and environmental pollution. On the other hand, when a hull is made of a plastic material, the buoyancy is relatively large, , The small boats of plastic hulls are in the limelight because of the high fuel efficiency of boats and the problem of environmental pollution.

There are various techniques related to a method of manufacturing such a boat of a plastic hull, and examples thereof are the techniques of Patent Documents 1 and 2. Patent Document 1 relates to a plastic boat including a rotatable plastic hull, Patent Document 2 relates to a method of manufacturing a plastic hull using rotational molding.

The above Patent Documents 1 and 2 describe a method of manufacturing a plastic hull by rotational molding using a plastic material and a method of reinforcing the strength of a plastic hull as a rotational molding.

Rotational molding is a kind of plastic molding method, which is a method of molding a hollow product with hollow interior using powdered plastic raw material. It is possible to make a complex shape product or a very large product with a mold with low production cost compared to other molding methods , A product formed by rotational molding is formed to have a uniform thickness and is not easily broken even by an external force. Rotational molding is a known technique widely used as a kind of plastic molding method.

In addition, as a method for reinforcing the strength of the plastic hull shown in the above-mentioned patent documents, the bending / recessed portion corresponding to the bending / contouring portion corresponding to the bending / A frame for strength reinforcement is attached to the inside of the mold, and the raw material powder is put into the mold and molded so that the frame is integrated with the hull. In this case, all of the molds are subjected to deformation to form bending / There is a complicated problem to attach.

1. Korean Patent Publication No. 2013-0008897 2. Korean Patent Publication No. 2013-0008898

The present invention has been developed in order to solve the problems of the prior art as described above, and it is an object of the present invention to provide a small boat plastic hull having a reinforcing means for reinforcing the strength of the bottom of the hull by integrally burying reinforcement means on the hull bottom, And an object of the present invention is to provide a rotary molding apparatus and a method of the same.

Particularly, the present invention is characterized in that the raw material powder is supplied in the state that the reinforcing means having the reinforcing wings formed longitudinally and laterally in the mold is provided, and then the end portions of the reinforcing means are integrally buried and integrally embedded in the hull, And an object of the present invention is to provide a rotary molding apparatus and method for a small boat plastic hull having a reinforcing means for allowing the means to be installed on the hull more easily.

In order to accomplish the above object, the present invention provides a rotary-molding apparatus for a small boat plastic hull having a reinforcing means according to the present invention, comprising a heating device for heating a metal mold, a first rotary shaft for rotating the metal mold in either direction, And a second rotating shaft which rotatably supports a rotary body supported by the first rotary shaft and rotatably supports the mold so as to rotate in a direction perpendicular to the first rotary shaft, wherein the reinforcing wing is formed longitudinally and laterally, The reinforcing means is fixed to the outer mold, and the reinforcement means, which is fixed to the hull by being embedded in the molten raw material powder in the process of molding the raw material powder into the mold and heating and rotating the mold, is installed inside the mold.

The fixing means may be any one of a fixing pin and a fixing bolt.

In another aspect of the present invention, there is provided a method of rotating a small boat plastic hull having a reinforcing means according to another aspect of the present invention. The method comprises rotating a die while rotating the die to insert the raw material powder into the die, A method for rotating a boat hull by molding and cooling the boat hull and forming a hull of the boat is characterized in that a reinforcing means is provided inside the metal mold and a fixing means is provided at the end of the reinforcing means so that the reinforcing means is fixed to the metal mold, And the end of the reinforcing means is buried in the wall of the hull to be integrated when the raw powder is melted and laminated on the inner wall of the mold in the heating and molding step for rotating the mold.

The apparatus and method for rotationally molding a small boat plastic hull having the reinforcing means according to the present invention are characterized in that the reinforcing means is preliminarily installed inside the metal mold in the process of rotational molding of the hull so that the reinforcing means is integrated with the rotationally formed hull, Can be provided.

Particularly, the raw material powder is put in a state in which the reinforcing means already made in the mold is installed, and the end of the reinforcing means is integrated with the hull to be formed by heating and rotation molding to deform the mold or form a complicated molding frame It is possible to easily manufacture the hull having the strength of the floor reinforced without the need of the hull.

1 is a plan view of an example of a rotary molding apparatus for a small boat plastic hull having a reinforcing means according to the present invention
2 is a cross-sectional view of a mold provided in a rotary molding apparatus for a small boat plastic hull having a reinforcing means according to the present invention
3 is a perspective view of an example of a reinforcement means provided inside a metal mold in a rotary molding apparatus and a method of a small boat plastic hull with reinforcement means according to the present invention.
4 is a perspective view of an example of a joint portion of a metal mold and a reinforcement means in a rotary molding apparatus for a small-boat plastic hull with reinforcement means according to the present invention.
Fig. 5 is a perspective view of another example of the engagement portion of the metal mold and the reinforcement means in the rotary molding apparatus for a small-boat plastic hull having the reinforcement means according to the present invention.
6 is a perspective view of another example of the joint portion of the metal mold and the reinforcement means in the rotary molding apparatus for a small boat plastic hull having the reinforcement means according to the present invention.
Fig. 7 is a sectional view of the end portion of the reinforcing means fixed by the fixing means shown in Fig. 6 and the assembled state of the hull and the mold
Fig. 8 is a sectional view of the end portion of the reinforcing means fixed by the fixing means shown in Fig. 6,

The present invention will be described in more detail with reference to the accompanying drawings, in which: FIG. 1 is a perspective view of a first embodiment of the present invention; And is intended to cover all modifications, equivalents, and alternatives falling within the spirit and scope of the invention.

In the following description, the same reference numerals are used for similar elements, and detailed explanations of the related art will be omitted when it is determined that the gist of the present invention may be blurred .

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotation molding of a small-sized boat plastic hull having a reinforcing means, and more particularly to an apparatus and a method for forming a hull so that the reinforcing means manufactured on the bottom of the hull, will be.

As shown in FIG. 1, the rotary molding apparatus for a small boat plastic hull with reinforcing means according to the present invention is provided with reinforcing means 10 for reinforcing the strength of the bottom of the hull 100 in the mold 100 .

As shown in Fig. 3, the reinforcing means 10 has the same shape as the bottom of the hull, and a plurality of reinforcing wings are integrally connected to one another vertically and horizontally.

The reinforcing means 10 may be made of metal or synthetic resin, but preferably made of the same material as the material of the hull. However, when the reinforcing means 10 is installed inside the metal mold 100, the raw powder is put into the mold 100, and when heated and rotated, the reinforcing means 10 receives heat like fuel powder. When the reinforcing means 10 is melted, It is preferable to use the material which melts at high temperature rather than the material of the hull.

The rotary molding apparatus for a small boat plastic hull having the reinforcing means according to the present invention is characterized in that the mold 100 is supported by the hull along the longitudinal direction of the hull (hereinafter referred to as & (Hereinafter, referred to as "left and right direction"), and this rotating means is the same as the conventional one. That is, the first rotary shaft 300 for rotating the mold in one direction and the rotary body 400b for rotatably supporting the first rotary shaft are rotatably supported to rotate the mold in the direction perpendicular to the first rotary shaft And a second rotating shaft 400 for supporting the metal mold 100. The heating apparatus 200 includes a heating unit 200 for heating the metal mold 100.

The heating device 200 and the rotating means may be modified in various ways to be similar to those used in a conventional rotary molding apparatus as described above.

1 shows the rotation shaft in the left-right direction as the first rotation axis 300 and the rotation axis in the front-rear direction as the second rotation axis 400, which will be described below as an example, but the claims are not limited thereto.

As shown in the drawing, the first rotating shaft 300 rotatably supports the mold in the front-rear direction, and the second rotating shaft 400 rotatably supports the mold in the left-right direction. The mold 100 is directly connected to the first rotating shaft 300 and the second rotating shaft 400 is installed on the rotating body 400b to which the first rotating shaft 400 is rotatably connected. When the second rotary shaft 400 is rotated, both the rotary body 400b, the first rotary shaft 100, and the metal mold are rotated in the front-rear direction and the first rotary shaft 400 (not shown) ), Only the mold 100 rotates.

The reinforcement means 10 is installed inside the rotating mold to melt the raw material powder and to be embedded in the molten raw material powder in which the ends of the reinforcing means are stacked in the process of being laminated on the inner wall of the mold 100.

Various types of heating apparatus 200 may be used as a means for applying heat to melt the raw powder. However, as shown in FIG. 1, the oven in which the inner space is sealed is used to cut off the outside air and the inside air, .

The fixing means 20 stably fixes the reinforcing means 10 in the mold which rotates when the mold is rotated in a state where the reinforcing means 10 is fixed inside the mold 100 as described above But is intended to fix the reinforcement means 10 inside the mold 100 so that it can be installed at a desired portion of the completed hull.

When the end of the reinforcing means 10 is in close contact with the mold, the end of the reinforcing means 10 may be exposed to the outer wall of the hull, which is completed by the rotation, so that the end of the reinforcing means 10, And the fixing means 20 fixes the reinforcing means 10 inside the mold so that a gap is maintained between the inner wall of the mold and the end portion of the reinforcing means at a predetermined interval.

The fixing means 20 may be variously modified. For example, the fixing means 20 may include a fixing pin 21 and a fixing bolt 22 as shown in FIGS.

However, this fixing means 20 can not only secure the reinforcing means 10 to the inside of the mold 100, but also to secure the reinforcement means to the wall of the completed hull, Since the fixing means 20 is separated from the hull 90 at the time of detaching the mold, the spacing protrusion 20d is further formed at the end of the reinforcing means so that the mold 100 and the reinforcing means 10 So that the distance between the end portions of the end portions of the first and second end portions is kept constant.

2 to 8, spacing protrusions 20d are formed on one side of the portion where the fixing means 20 is installed so that the ends of the reinforcing means 10 are separated from the inner wall of the mold 100 by a predetermined distance The outer peripheral surface of the spacing projection 20d is formed with an engaging portion such as an engaging groove or an engaging projection so that the engaging portion is filled with the raw material powder constituting the body 90, So that the coupling force between the means 10 can be increased.

4, the fixing pin 21 as an example of the fixing means 20 includes a pinhole 20h formed at the end of the reinforcing means 10 through a through hole 100h formed through the mold 100, The fixing bolt 22 which is another example of the fixing bolt 22 is inserted and fixed in the through hole 100h formed in the metal mold 100 as shown in Fig. Is fitted in the hole (22n) and is screwed and fixed.

Further, at the end of the reinforcing means 10, as shown in Figs. 6 to 8, a coupling reinforcing vane 23 may be further formed.

As shown in Figs. 6 and 8, the coupling reinforcing vanes 23 are provided inside the mold with a predetermined spacing from the inner wall of the mold. After the hull 90 is rotationally formed, And is buried in the wall of the hull 90 as shown in the figure.

A plurality of through holes 23h are formed in the coupling reinforcing vane 23 so that the molten raw material powder is filled in the through holes 23h during the rotational molding process so that the ends of the reinforcing means 10 are more firmly attached to the hull 90). &Lt; / RTI >

7, the reinforcing means 10 is fixed to the inside of the metal mold 100 by the fixing bolt 22 which is a fixing means, and the spacing protrusion 20d is provided at the end of the reinforcing means 10 The gap between the inner wall of the mold is maintained at a predetermined interval, and the coupling reinforcing vanes 23 are also spaced apart from the inner wall of the mold 100.

When the rotation molding of the hull 90 is completed in this state, the formation of the hull 90 in a state where the separation protrusions 20d and the coupling reinforcing vanes 23 are embedded in the wall of the hull 90 as shown in Fig. 7 When the mold 100 is separated from the hull, the hull 90 is formed in a state in which the spacing protrusions 20d and the coupling reinforcing vanes 23 are embedded as shown in Fig.

The forming method using the rotary molding apparatus of the small boat plastic hull having the reinforcing means according to the present invention having been described above has already been explained in the description of the apparatus, .

The basic process of the present invention is a process for introducing a raw material into which a raw material for plastic powder is introduced into a mold composed of an inner mold (or an upper mold) and an outer mold (or a lower mold) A cooling step of cooling the mold after molding, and a demolding step of opening the upper mold and taking out the molded product after cooling is completed.

In the present invention, a variety of thermoplastic materials may be used as the material of the powder raw material. For example, polyethylene, polypropylene, polycarbonate, polyamide, polyvinyl chloride (PVC) and the like can be used. Among these materials, polyethylene has a long lifetime due to no corrosion due to seawater, , High abrasion resistance, good flowability and low thermal shock resistance, and is widely used.

The mold is made according to the shape of the finished hull, and can be made of various materials such as metal or ceramics. It is preferable to use light aluminum alloy with high thermal conductivity and high strength. That is, since the powder raw material supplied to the inside of the metal mold must be melted by applying heat from the outside of the rotating mold, a metal having excellent thermal conductivity is used so that heat applied from the outside can be easily transferred to the inside, It is advisable to use light metal as the material of the mold to reduce the load on the device.

When the material and the mold are ready, the mold is assembled and the molding is carried out. The mold is composed of an inner mold and an outer mold as in the case of an ordinary injection mold, and each of the inner and outer molds can be formed into a plurality of pieces.

At this time, the reinforcing means (10) is installed inside the mold before assembling the mold. The method of fixing the reinforcing means to the inside of the mold may be performed by using various fixing means as described above.

When the reinforcing means is installed inside the mold, the powder material is injected into the outer mold, and the inner mold is assembled inside the outer mold to assemble the mold having the inner space of the boat hull shape.

The metal mold thus assembled is installed in a rotating device to be rotated, and a heating means for supplying heat to the periphery is provided. Such a rotating device or a heating device can be usually used by modifying the device used in the rotary molding method to suit the rotational molding of a ship.

When the mold is heated and rotated while the reinforcing means is installed in the mold, the raw material powder is melted and laminated on the inner wall of the mold to form a hull. In this process, the ends of the reinforcing means are formed by laminating the molten raw material powders It is buried in the wall and integrated with the hull.

When the molding is completed in the molding step, the mold is cooled through the cooling step. The cooling step may be carried out by various methods, but it may vary depending on the properties of the material of which the hull is made. Depending on the material, cold air may be supplied to rapidly cool or slowly cool at room temperature, which may be tailored to the characteristics of conventional thermoplastic materials, and a detailed description thereof will be omitted.

When the cooling is completed, the process of the present invention is completed after the demolding process of taking out the hull as a molded product from the mold.

10: Reinforcement means
20: Fixing means
20d:
21: Fixing pin
22: Fixing bolt 22b: Nut hole
23: joint reinforcing wing 23h: through hole
90: Hull
100: Mold
200: Heating device
300: first rotating shaft
400: second rotary shaft
400b:

Claims

A heating device 200 for heating the mold 100, a first rotating shaft 300 for rotating the mold in either direction and a rotary body 400b for rotatably supporting the first rotating shaft are rotatably supported And a second rotation shaft (400) for supporting the mold so as to rotate in a direction perpendicular to the first rotation axis,
And the end portion is fixed to the outer mold by the fixing means 20 so that the raw material powder is charged into the mold and then heated and rotated to form the hull And a reinforcement means (10) in which the end portion is embedded in the raw material powder and fixed to the hull, is provided inside the metal mold.

The method according to claim 1,
Wherein the fixing means (20) is any one of a fixing pin and a fixing bolt.

A method for rotating a boat hull, comprising the steps of putting a raw material powder into a mold, applying heat while rotating the mold, causing the raw material powder to melt and adhere to the inner wall of the mold,
The reinforcing means is provided inside the mold, the reinforcing means is fixed to the mold, the heat is applied, and the raw powder is melted in the heating and molding step for rotating the mold, And the end of the reinforcing means is buried in the wall of the hull to be integrated with each other in the process of forming the hull.