JP3282001B2 - Mold heating or cooling device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for molding a resin by heating or cooling a mold. Usually, when molding a thermoplastic synthetic resin in a mold, the mold is heated or cooled as necessary during a cycle from injection of the raw material into the mold to molding and release. .

[0002]

2. Description of the Related Art In the case of conventional foam molding using expanded polystyrene, for example, high-temperature steam is supplied to perform heat-foaming fusion, then cooling water is supplied in place of steam, and suction means such as a vacuum pump is used. Generally, the mold and the molded body are vacuum-cooled while the heat exchange chamber is in a reduced pressure state.

[0003]

In the conventional heating and cooling apparatus for a mold, there has been a problem that the entire surface of the mold and the formed body cannot be uniformly cooled, and uneven cooling occurs partially. This is because the cooling water does not reach the entire surface of the heat exchange chamber on the inner surface of the mold, and there is a portion where the cooling water does not adhere.Particularly, the shape of the mold has many irregularities. In the case of a non-uniform shape, there are many places where the cooling water cannot reach, and cooling unevenness occurs.

Accordingly, it is an object of the present invention to provide a mold heating or cooling apparatus which does not cause cooling unevenness by making the cooling water reach the entire surface of the heat exchange chamber.

[0005]

The structure of the mold heating or cooling device of the present invention is as follows. A mold having a heat exchange chamber for heating or cooling and a molding section, and a fluid conduit for supplying a heating fluid or a cooling fluid to the heat exchange chamber,
A valve means for controlling the passage of a fluid provided in the fluid conduit, and a suction means for sucking the fluid in the heat exchange chamber, wherein the inside of the heat exchange chamber is substantially shaped like an inner surface of the heat exchange chamber. A porous body along the shape is arranged with a slight gap therebetween.

[0006]

The cooling fluid supplied from the cooling fluid pipeline to the heat exchange chamber reaches the heat exchange chamber by arranging the porous body having a shape substantially along the inner surface of the heat exchange chamber through the gap. You can reach the whole area of the room. The cooling water reaching the entire surface of the heat exchange chamber uniformly cools the mold and the molded body with water, and furthermore, the cooling water is evaporated under reduced pressure to perform vacuum vaporization cooling with its heat of vaporization, The vaporized vapor passes through the porous body and is sucked by the suction means and discharged out of the system.

[0007]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. In FIG. 1, a pair of left and right molds 1 and 2, a porous body 5 disposed in the molds 1 and 2, a heating fluid pipeline 25 and a cooling fluid pipeline 3,
The suction means 4 constitutes a mold heating or cooling device.

The molds 1 and 2 have hollow portions 6 and 7 formed therein, and the hollow portions 6 and 7 are used as heat exchange chambers. The central part of the molds 1 and 2 is used as a molding part 13, and a molding material (not shown) is injected and molded in the molding part 13. Inside the heat exchange chambers 6 and 7, the porous body 5 having a substantially U-shaped cross section is arranged along the entire shape of the molding section 13 and a part of the molds 1 and 2. Slight gaps 8 and 9 are provided between the porous body 5 and the inner peripheral surfaces of the molds 1 and 2 such that the cooling fluid can flow down. The porous body 5 includes a porous body using ceramics or metal,
A porous body using a synthetic resin or a synthetic rubber, a polymer film, or the like can be used. Valve 11 on top of molds 1 and 2
Is connected to the cooling fluid pipeline 3 via the. When the cooling fluid supplied from the cooling fluid pipe 3 is injected into the heat exchange chambers 6, 7, the cooling fluid flows down the gaps 9, 8.

A plurality of pores 30 are provided between the molding section 13 and the heat exchange chambers 6 and 7. As shown in a partially enlarged cross-sectional view of FIG.
The valve is arranged so as to be biased toward the valve seat 32 side, and is a check valve that allows only the passage of the fluid from the molded portion 13 to the heat exchange chamber 7.
The diameter of the pores 30 may be small for sucking the heat exchange chambers 6 and 7 by the suction means 4 as described later.
It can be from about 05 mm to about 0.1 mm. This check valve prevents the high-pressure fluid for heating from escaping to the forming portion 13 when a high-pressure fluid is supplied from the fluid line 25 for heating.

The heat exchange chambers 6 and 7 are connected to the heating fluid line 25 via headers 35 and 36. The heating fluid supplied from the fluid conduit 25 is supplied to the heat exchange chambers 6 and 7 from the headers 35 and 36. A pressure control valve 26 for controlling the supply steam pressure and an on-off valve 27 are provided in the heating fluid line 25.
Attach.

The suction means 4 is connected to the lower part of the headers 35 and 36. The suction means 4 includes an ejector 14, a tank 15, and a circulation pump 16. The ejector 14 includes a suction unit 17 having a built-in nozzle and a diffuser 18.
The suction part 17 and the headers 35 and 36 are connected by the pipe 19. The diffuser 18 is connected to the tank 15 and the tank 1
5 is connected to the suction port of the circulation pump 16 and the discharge port is connected to the suction section 17 of the ejector 14. The ejector 14 generates a suction force at a built-in nozzle portion by circulating a fluid in a tank 15 by a circulation pump 16 and passing the fluid to a suction portion 17.

Although not shown, a liquid level sensor for detecting the liquid level inside the tank 15 and a temperature sensor 21 for detecting the liquid temperature are mounted on the tank 15, and a cooling fluid supply pipe 20 is controlled at the upper part. Connect via valve 22.

Next, the operation will be described. When heating the molds 1 and 2, the set pressure value of the pressure control valve 26 is set to a predetermined value, the on-off valve 27 is opened, and the steam for heating is supplied from the heating fluid pipe 25 to the headers 35 and 36. Are supplied to the heat exchange chambers 6 and 7. The supplied steam passes through the porous body 5 and heats the molds 1 and 2, and the steam condenses and becomes condensed. The condensate is supplied to the ejector 14 of the suction means 4 by the valve 37 and the steam trap 2.
3 and is discharged to the outside of the system as needed when the liquid level in the tank 15 reaches the tank 15 and rises.

The heating temperature can be appropriately set by adjusting the set pressure of the pressure control valve 26 and the temperature of the water passing through the suction force of the suction means 4. For example, if the heating temperature is 100
If it is desired to set a relatively high temperature of not less than degree C, the pressure control valve 26
Is set to a pressure equal to or higher than the atmospheric pressure, and the suction force of the suction means 4 is set slightly lower than that pressure. When heating the molds 1 and 2 with relatively low temperature steam of 100 ° C. or less, the set pressure of the pressure control valve 26 is set to a vacuum pressure equal to or less than the atmospheric pressure, and the suction force of the suction means 4 is transferred to the tank 15. This can be achieved by supplying cooling water from the cooling water supply pipe 20 to increase the temperature of the circulating water by lowering the temperature and by slightly lowering the pressure set by the pressure control valve 26.

Next, in the case of cooling, the cooling fluid is supplied to the heat exchange chambers 6 and 7 from the cooling fluid pipe 3 instead of supplying steam, and the suction means 4 is driven to drive the heat exchange chambers 6 and 7. By setting the inside to a reduced pressure state, the supplied cooling fluid cools by removing the heat of the molds 1 and 2 and evaporating them. In this case, the cooling fluid reaches the gaps 8 and 9 between the molds 1 and 2 and the porous body 5 due to the arrangement of the porous bodies 5 and reaches the entire molds 1 and 2 of the forming part 13. By uniformly cooling the uneven portion 13, the cooling unevenness does not occur.

The vaporized vapor and a part of the cooling fluid remaining without being vaporized are sucked by the suction section 17 of the suction means 4 and are stored in the tank 1.
Reaches 5. Further, the gas generated in the molding part 13 can be appropriately removed by sucking the gas from the fine holes 30 provided at an arbitrary position and the check valve inside the fine holes 30 by the suction means 4.

[0017]

According to the present invention, the cooling fluid reaches the entire inner surface of the heat exchange chamber by arranging the porous body along the inner surface shape of the heat exchange chamber through the gap. Even a mold and a molded article having a complicated shape as described above can be uniformly cooled, and uneven cooling can be prevented.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an embodiment of a mold heating or cooling device of the present invention.

FIG. 2 is a partially enlarged sectional view of a pore in FIG.

[Explanation of symbols]

 1, 2 mold 3 cooling fluid pipe 4 suction means 5 porous body 6, 7 heat exchange chamber 8, 9 gap 13 forming part 14 ejector 15 tank 16 circulation pump 17 suction part 25 heating fluid pipe

Claims (1)

(57) [Claims] 1. A mold having a heat exchange chamber for heating or cooling and a molding portion, a fluid pipe for supplying a heating fluid or a cooling fluid to the heat exchange chamber, and provided in the fluid pipe. Comprising a valve means for controlling the passage of the fluid, and a suction means for sucking the fluid in the heat exchange chamber, wherein a porous body having a shape substantially along the inner surface shape of the heat exchange chamber is provided inside the heat exchange chamber. A heating or cooling device for a mold, wherein the device is disposed with a slight gap therebetween.