JP3312191B2 - 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-foam fusion, then cooling water is supplied in place of steam, and suction means such as a vacuum pump is used. In general, a mold and a compact are vacuum-evaporated and cooled while the heat exchange chamber is in a reduced pressure state.

[0003]

The conventional heating and cooling apparatus for a mold has a problem that sufficient cooling efficiency cannot be obtained yet. That is, the vaporized vaporized by cooling in the heat exchange chamber is convected by suction by a vacuum pump to continuously perform vacuum vaporization cooling.However, depending on the shape of the heat exchange chamber and the connection point of the vacuum pump, the vacuum may be reduced. This is because sufficient convection cannot be obtained with the pump alone, and as a result, the efficiency of evaporative cooling is reduced. If a sufficient cooling efficiency cannot be obtained, the distribution of the cooling temperature becomes non-uniform, resulting in partial uneven cooling.

Accordingly, a technical object of the present invention is to provide a heating or cooling device for a mold which does not cause cooling unevenness by increasing the convection of vaporized vapor in a heat exchange chamber to increase the cooling efficiency of vaporizing cooling. Is to get.

[0005]

The construction of the mold heating or cooling apparatus of the present invention is as follows. A mold having a heat exchange chamber for heating or cooling and a molding section, a fluid line for supplying a heating fluid or a cooling fluid to the heat exchange chamber, and passing of a fluid provided in the fluid line. In a device comprising a valve means for controlling and a suction means for sucking a fluid in the heat exchange chamber, a plurality of pores are formed between the molding part and the heat exchange chamber.
A plurality of through-holes are provided to allow the plurality of pores to pass from the molding section to the heat exchange chamber.
A check valve that allows the passage of fluid is built in , a cooling fluid passage pipe is disposed in the heat exchange chamber, and a nozzle is formed in the cooling fluid passage pipe.

[0006]

[Function] By disposing a cooling fluid passage pipe having a nozzle in the heat exchange chamber, the cooling fluid is ejected from the nozzle and adheres to the surface of the mold, whereby the mold is cooled. Stay in the heat exchange chamber. Since the cooling fluid passes through the cooling fluid passage pipe in the heat exchange chamber and is in a low temperature state, the vaporized vapor in the heat exchange chamber contacts the cooling fluid passage pipe and is absorbed by the suction means. It condenses and becomes liquid again. Accordingly, the convection speed of the vaporized vapor is higher by the rate of condensation in the cooling fluid passage pipe than in the case where the vaporized vapor is merely sucked by the suction means. The liquid that has been vaporized and condensed, the remaining vaporized vapor that has not been condensed, and a part of the cooling fluid are 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, cooling fluid passage pipes 5 and 8 disposed inside the molds 1 and 2, a cooling fluid pipe 3 and a heating fluid pipe 25, and suction The 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. Through holes 9 and 10 are provided in the upper part of the heat exchange chambers 6 and 7, and the valve 1 is provided in the upper part.
It is connected to the cooling fluid pipe 3 via 1 and 12. Elongated cooling fluid passage pipes 5 and 8 are arranged in the heat exchange chambers 6 and 7, and a plurality of nozzles 38, 39 and 40 are provided on the molding section 13 side. The cooling fluid passage pipes 5 and 8 can be made of metal such as copper or stainless steel, and can also be made of ceramics or the like. The lower portions of the cooling fluid passage pipes 5, 8 are connected to the fluid discharge pipes 24, 28 via valves.

In this embodiment, the nozzles 38, 39,
Although the example in which 40 is provided on the molding section 13 side is shown, the installation position and the number of installed nozzles can be appropriately changed and adjusted according to the shapes of the dies 1 and 2. Further, in this embodiment, the example in which the cooling fluid passes from the top to the bottom of the plurality of cooling fluid passage pipes 5 and 8 has been described, but the single cooling fluid passage pipe is used to spirally rotate in the heat exchange chamber. It can also be attached. In order to increase the surface area of the cooling fluid passage pipes 5 and 8 to improve the degree of cooling, fins may be provided on each cooling fluid passage pipe, though not shown.

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 is for preventing the high-pressure fluid for heating from escaping to the forming part 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 fluid supplied from the fluid line 25 is supplied from the headers 35 and 36 to the heat exchange chambers 6 and 6.
7 is supplied. A pressure control valve 26 for controlling the supply steam pressure and an on-off valve 27 are attached to the heating fluid pipeline 25.

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 heats the molds 1 and 2, and the steam whose heat has been removed is condensed and condensed. Condensation is suction means 4
Is sucked into the ejector 14 via the valve 37 and the steam trap 23, and reaches the tank 15 and is discharged out of the system as needed when the liquid level in the tank 15 becomes high.

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 cooling fluid passage pipes 5 and 8 from the cooling fluid pipeline 3 and the valves 11 and 12 in place of the steam supply, and the suction means 4 is driven. By setting the pressure inside the heat exchange chambers 6 and 7 to a reduced pressure, the cooling fluid supplied from the nozzles 38
The molds 1 and 2 are cooled by depriving the heat of 2 and vaporizing. In this case, since the cooling fluid passes through the cooling fluid passage pipes 5 and 8 and is in a low temperature state, the vaporized by the cooling stays in the heat exchange chambers 6 and 7. The liquid is cooled and condensed on the surfaces of the heat exchangers 5 and 8, becomes a liquid again, and drops below the heat exchange chambers 6 and 7. By condensing the vaporized vapor again, the convection of the vaporized vapor is promoted, and the cooling efficiency can be increased.

The dropped liquid, vaporized vapor remaining without condensing, and a part of the cooling fluid remaining without vaporizing are sucked by the suction part 17 of the suction means 4 to reach the tank 15. 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.

[0018]

According to the present invention, the convection of the vaporized vapor in the heat exchange chamber can be accelerated by disposing the cooling fluid passage pipe having the nozzle formed in the heat exchange chamber, and the cooling efficiency of the vacuum vaporization cooling can be increased. And cooling unevenness can be prevented. Further, by passing the cooling fluid through the cooling fluid passage pipe, the degree of cooling of the vaporized vapor can be increased, and the cooling efficiency can be further increased.

[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]

 Reference Signs List 1, 2 Mold 3 Cooling Fluid Pipe 4 Suction Means 5 Cooling Fluid Passing Pipe 6, 7 Heat Exchange Chamber 8 Cooling Fluid Passing Pipe 13 Molding Section 14 Ejector 15 Tank 16 Circulating Pump 17 Suction Section 25 Heating Fluid Pipe 38 , 39, 40 nozzles

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. and valve means for controlling the passage of fluids, in what comprising a suction means for sucking the fluid in the heat exchange chamber, the molding unit
And a plurality of pores are provided between the heat exchange chamber and the plurality of heat exchange chambers.
Inverse that allows the passage of fluid from the molding to the heat exchange chamber in the pores
A heating or cooling device for a mold, comprising a stop valve, a cooling fluid passage pipe disposed in a heat exchange chamber, and a nozzle formed in the cooling fluid passage pipe.