JP3282009B2 - 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 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 passage of a fluid provided in the fluid conduit, and suction means for sucking the fluid in the heat exchange chamber, wherein a mold cooling fluid injection nozzle is provided in the heat exchange chamber;
And a fluid injection nozzle for condensing vaporized vapor.

[0006]

The mold is cooled by injecting a cooling fluid from the mold cooling fluid injection nozzle into the heat exchange chamber, and the vaporized vapor due to the cooling stays in the heat exchange chamber. On the other hand, by providing a fluid injection nozzle for vaporization vapor condensation in the heat exchange chamber,
The vaporized vapor in the heat exchange chamber comes into contact with the fluid injected from the vaporized vapor condensing fluid injection nozzle, and is condensed by the suction means to become a liquid again. Accordingly, the convection speed of the vaporized vapor is increased by the rate condensed by the injected fluid from the vaporized vapor condensing fluid injection nozzle, as compared with 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, mold cooling fluid injection nozzles 5 and 8 arranged at the top of the molds 1 and 2, vaporized vapor condensing fluid injection nozzles 9 and 10, and heating The fluid channel 25 for cooling, the fluid channel 3 for cooling, and the suction means 4 constitute 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. The mold cooling fluid injection nozzles 5 and 8 are attached to the upper portions of the heat exchange chambers 6 and 7 so that the fluid is mainly injected into the molding section 13, and at a position away from the molding section 13. The fluid injection nozzles 9 and 10 for vaporizing vapor condensation are attached substantially vertically downward. Above each of the nozzles 5, 8, 9, 10 there is provided a branch line 11, 12 and a cooling fluid line 3 via a valve.
Connect. In this embodiment, an example is shown in which only one of the nozzles 5, 8, 9, and 10 is mounted above the molds 1 and 2. However, the present invention is not limited to the upper side and may be laterally or downwardly. , A plurality of them can be attached.

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 is condensed and condensed. Condensation is performed by the ejector 1 of the suction means 4.
4 is sucked through the valve 37 and the steam trap 23,
When the liquid reaches the tank 15 and the liquid level in the tank 15 increases, the liquid is discharged out of the system as needed.

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, when cooling, the cooling fluid is supplied to the heat exchange chambers 6 and 7 from the cooling fluid pipe 3 and the branch pipes 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 state, the cooling fluid supplied from the mold cooling fluid injection nozzles 5 and 8 deprives the molds 1 and 2 of heat and evaporates, thereby cooling the mold 1. ,
Cool 2 In this case, since the cooling fluid is injected from the vaporized vapor condensing fluid injection nozzles 9 and 10 at the upper portions of the heat exchange chambers 6 and 7, the vaporized vapor by the cooling is transferred to the heat exchange chambers 6 and 7.
, But is cooled by the condensing fluid, condensed, becomes a liquid again, and drops below the heat exchange chambers 6, 7. By condensing the vaporized vapor again with the condensing fluid, the convection of the 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.

In this embodiment, an example is shown in which the fluid injection nozzles 9 and 10 for condensing vaporized vapor are orifice-shaped and the fluid is injected linearly. By making the shape into a cylindrical shape, a prismatic shape, a cross shape, or a T-shape, the area where the injected fluid and the vaporized vapor come into contact with each other can be increased to further promote the vaporized vapor to be condensed. .

[0018]

According to the present invention, the convection of vaporized vapor in the heat exchange chamber can be accelerated by providing the mold cooling fluid injection nozzle and the vaporized vapor condensing fluid injection nozzle in the heat exchange chamber. In addition, the cooling efficiency of vacuum evaporative cooling can be increased to prevent uneven cooling.

[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 pipeline 4 Suction means 5 Mold cooling fluid injection nozzle 6, 7 Heat exchange chamber 8 Mold cooling fluid injection nozzle 9, 10 Fluid injection nozzle for vaporized vapor condensation 13 Molding section 14 Ejector 15 Tank 16 Circulation pump 17 Suction unit 25 Heating fluid line

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. Valve means for controlling the passage of the fluid, and suction means for sucking the fluid in the heat exchange chamber, wherein a fluid injection nozzle for mold cooling, a fluid injection nozzle for vaporized vapor condensation, A heating or cooling device for a mold, comprising: