JPH0450088Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention relates to a cooling device for a mold used when molding plastic products.

(Prior art and its problems) Conventionally, this type of cooling device cools the internal cooling liquid by guiding the refrigerant pipe from the refrigerator directly to the heat exchange water tank.
It was common practice to cool the mold by circulating this cooling liquid within the mold. However, when using this method, not only the size of the refrigerator becomes large but also the electric capacity becomes large, which is not only uneconomical but also has disadvantages such as taking up more space than necessary.

(Means for solving the problem) This project was researched to solve the above-mentioned drawbacks of conventional cooling devices. It was found that by cooling the cooling liquid in the water tank and circulating this cooling liquid within the mold, sufficient cooling could be achieved using a small refrigerator with a small electric capacity.

To explain the present invention with reference to the illustrated embodiment, it consists of a heat exchange water tank 1 and heat pipes 2, 2..., and the heat exchange water tank 1 contains an appropriate amount of a coolant 3 such as ethylene glycol. Circulation pump 4,
Guided into the mold 6 by the circulation pipe 5, the mold 6
After cooling, it returns to the heat exchange water tank 1.

The heat pipe 2 consists of an outer cylinder 8 having a wick (a net-like membrane that causes capillary action) 7 provided in contact with the inner wall, and a U-shaped branch heat medium pipe 9 inserted into the outer cylinder 8. The inside of the outer cylinder 8 is evacuated and an appropriate amount of working fluid 10 is contained, and a coupler 1 with a valve is installed at both ends of the branch heat transfer pipe 9.
1 and 11 are installed. 12 is a sealed lid. The branch heat medium pipe 9 of the heat pipes 2, 2... is connected to the coupler 1.
The refrigerant pipes 14 and 15 are connected to reciprocating refrigerant pipes 14 and 15 from the refrigerator 13 via pipes 1 and 11, and a plurality of pipes are inserted into the center of the heat exchange tank 1.

(Operation) The present invention is realized as described above, and the refrigerator 1
3, the refrigerant flowing through the former refrigerant pipe 14 is branched to the branch heat medium pipe 9 of each heat pipe 2, 2, and cools the heat pipe 2, 2... The working fluid 10 sealed in the cylinders 2, 2... acts quickly, that is, the heat of the uncooled cooling fluid 3 in the heat exchange tank 1 is taken away from the inner wall of the outer cylinder 8, and the working fluid 10 quickly evaporates. The evaporated working fluid 10 is cooled in the branch heat transfer pipe 9 and condensed to become a liquid.The working fluid 10, which has become a liquid due to the capillary pressure of the wick 7, is returned to the inner wall of the outer cylinder 8.
Evaporation and condensation are repeated again, and the upper and lower parts of the heat pipes 2, 2... are uniformly cooled. As a result, the cooling liquid in the heat exchange water tank 1 is quickly and uniformly cooled to the required temperature. The refrigerant that has passed through the branch refrigerant pipe 9 passes through a second refrigerant pipe 15 and is cooled and circulated within the refrigerator 13. The cooled liquid flows into the mold 6 through the circulation pipe 5 and is cooled.

The working fluid 10 used for this purpose is a liquid that evaporates in a vacuum at a temperature higher than the temperature to be cooled.

(Effects) As mentioned above, this project consists of a heat exchange tank containing a cooling liquid and a number of heat pipes installed in the heat exchange tank, and the cooling liquid in the heat exchange tank is pumped into the mold via a circulation pump. The heat pipe is made to have a vacuum inside and is filled with an appropriate amount of working fluid, and can be cooled freely via the branched heat medium pipe by the refrigerant pipe from the refrigerator, so that the coolant in the heat exchange water tank can be sufficiently cooled with a relatively small refrigerator and is economical.

Experimental results: 400 x 500 x 1000 with normal mold cooling
In order to heat the coolant to -20℃ in a mm heat exchange water tank and send it into the mold, 20 50.8〓 heat pumps 2, 2, etc. are installed, and a refrigerator of 0.75kw (1) is sufficient for cooling. It is economical if the electric capacity is one-third of that of conventional cooling methods. Furthermore, since the heat pipe has a thin outer cylinder, a large number of heat pipes can be installed upright within the heat exchange tank, allowing for space-saving and efficient cooling.

Also, due to the action of the working fluid inside the heat pipe, the upper and lower parts of the heat pipe are quickly cooled to a uniform temperature.
This allows the cooling liquid to be cooled uniformly and quickly, and is suitable for cooling molds that require precision in cooling temperature.

[Brief explanation of the drawing]

FIG. 1 is an explanatory cross-sectional view of a mold cooling device according to the present invention, FIG. 2 is an explanatory plan view thereof, and FIG. 3 is a cross-sectional view of a heat pipe. 1 is a heat exchange tank, 2 is a heat pipe, 3 is a cooling liquid, 4 is a circulation pump, 5 is a circulation pipe, 6 is a mold, 7 is a wick, 8 is an outer cylinder, 9 is a branch refrigerant pipe,
10 is a working fluid, 13 is a refrigerator, 14 is a forward refrigerant pipe, and 15 is a return refrigerant pipe.

Claims (1)

[Scope of utility model registration request] It consists of a heat exchange tank containing a cooling liquid and a number of heat pipes installed in the heat exchange tank.The cooling liquid in the heat exchange tank can be freely circulated inside the mold via a circulation pump, and the heat pipes A suitable amount of working fluid is sealed in a vacuum and a branch heat transfer pipe is inserted into the mold, and these branch heat transfer pipes are connected to the refrigerant pipe from the refrigerator, allowing the refrigerant to be freely fed into the mold. Cooling system.