JPH0450089Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Industrial Application Field) The present invention relates to a cooling device for multiple molds with different cooling temperatures, which is used when molding plastic products and the like.

(Prior art and its problems) Conventionally, when cooling multiple molds, refrigerant pipes from multiple refrigerators are led directly to individual cold water tanks to cool the internal cooling liquid, and this cooling liquid is used to cool the molds. It was common practice to cool the mold by circulating it inside the mold. However, this method not only requires a plurality of refrigerators but also becomes large in size and has a large electric capacity, which is not only uneconomical but also has disadvantages such as taking up more space than necessary.

(Means for Solving the Problems) This project was researched to solve the above-mentioned drawbacks of conventional cooling devices. A large number of heat pipes are installed in each of the cold water tanks, and the coolant at different cooling temperatures in these cold water tanks can be freely circulated within the mold via a circulation pump, and the inside of the heat pipe is depressurized by vacuum. An appropriate amount of working fluid is sealed and branch heat transfer pipes are inserted, and both ends of these branch heat transfer pipes are connected to the reciprocating heat transfer pipes from the refrigerator to allow free circulation of the refrigerant. As a result, it was found that sufficient cooling could be achieved with a relatively small refrigerator with a small electric capacity.

To explain the present invention with reference to the illustrated embodiment, two cold water tanks 1, 1 with different cooling temperatures, a large number of heat pipes 2, erected in each of these cold water tanks 1, 1',
2..., but one cold water tank 1 has a large number of heat pipes 2, 2 erected to serve as a cold water tank on the low temperature side, and the other cold water tank 1' has a smaller number of heat pipes 2, 2 erected. It is used as a cold water tank on the high temperature side. The cold water tanks 1 and 1' contain a cooling liquid 3 such as ethylene glycol,
This coolant 3, 3' is guided into the molds 6, 6' by circulation pumps 4, 4' and circulation pipes 5, 5', and the cooling liquid 3, 3' is guided into the molds 6, 6' to cool the molds 6, 6'. After cooling, it returns to the cold water tank 1, 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.
They are connected to reciprocating heat medium 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 cold water tanks 1 and 1'.

In the figure, 16 is a compressor in the refrigerator 13, 17 is an air-cooled condenser, 18 is a liquid receiving tank, 19 is a dryer, 20 is a sight glass, 21 is an expansion valve, 22 is an accumulator, and 23 and 23 are electromagnetic The valve automatically opens and closes depending on the temperature of the coolant in the cold water tank.

(Operation) The present invention is realized as described above, and the refrigerator 1
3, the refrigerant flowing through the former heat medium pipe 14 is branched to the branch heat medium pipe 9 of each heat pipe 2, 2... to cool the heat pipes 2, 2.... As a result, the working fluid 10 sealed in the heat pipes 2, 2... acts quickly, that is, the heat of the uncooled cooling fluid 3, 3' in the cold water tank 1, 1' is transferred to the outer cylinder 8. The working fluid 10 taken from the inner wall quickly evaporates, and this evaporated working fluid 10 is transferred to the branch heat transfer pipe 9.
The working fluid 10, which has been cooled and condensed into a liquid due to the capillary pressure of the wick 7, is returned to the inner wall of the outer cylinder 8, where it repeats evaporation and condensation again, uniformly cooling the top and bottom of the heat pipes 2, 2... be done. As a result, the cooling liquid in the cold water tanks 1, 1' is quickly and uniformly cooled to the required temperature. The refrigerant that has passed through the branch heat medium pipe 9 passes through a second heat medium pipe 15 and is cooled and circulated within the refrigerator 13. The cooled liquid flows through the circulation pipe 5 into the molds 6 and 6' having different cooling temperatures and is cooled. When only one mold is to be cooled, the solenoid valve of the other cold water tank 1 or 1' may be closed manually.

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

(Effects) As mentioned above, this system consists of multiple cold water tanks containing coolant with different cooling temperatures and a large number of heat pipes installed in the cold water tanks, and the coolant in the cold water tank is cooled via a circulation pump. The heat pipe can be freely circulated in multiple molds with different temperatures, and the inside of the heat pipe is evacuated and an appropriate amount of working fluid is sealed, and the heat pipe can be freely cooled via a branch heat medium pipe from a refrigerator. Therefore, the cooling liquid in the cold water tank can be sufficiently cooled with a relatively small refrigerator, and it is economical because a single refrigerator can be installed to simultaneously cool a plurality of molds having different cooling temperatures. In addition, since a branch heat transfer pipe is inserted into the heat pipe, a large number of items can be stored in a small space and cooling can be performed quickly.

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 drawings]

FIG. 1 is an explanatory diagram of piping 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, 1' is a cold water tank, 2 is a heat pipe, 3,
3' is cooling liquid, 4, 4' are circulation pumps, 5, 5' are circulation pipes, 6, 6' are molds, 7 is wicks, 8
1 is an outer cylinder, 9 is a branch heat medium pipe, 10 is a working fluid, 13 is a refrigerator, 14 is a former heat medium pipe, and 15 is a return heat medium pipe.

Claims (1)

[Scope of utility model registration request] It consists of multiple cold water tanks containing coolant at different cooling temperatures and a large number of heat pipes installed in each of these cold water tanks. The inside of the heat pipe is vacuum-depressurized and an appropriate amount of working fluid is sealed in it, and branch heat transfer pipes are inserted.Both ends of these branch heat transfer pipes are connected to A mold cooling device that is connected to a heat medium pipe and allows free circulation of refrigerant.