JPH11286019A - Cooling mechanism for plastic molding machine and method for cooling - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a cooling mechanism for a plastic molding machine for effectively preventing an obstacle generated by using water and a method for cooling. SOLUTION: An indoor unit 2 for cooling the plastic molding machine 1 by circulating a medium to the machine 1 is installed in a room S where the machine 1 is installed. An outdoor unit 3 for cooling the medium of the unit 2 by circulating cooling medium except water to the unit 2 is disposed out of the room O.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a cooling mechanism and a cooling method for a plastic molding apparatus.

[0002]

2. Description of the Related Art In general, a plastic molded product is formed by melting a plastic raw material by an injection molding machine installed in a factory, injecting the molten resin into a mold, cooling after molding.

Conventionally, for example, as shown in FIG. 6, a cooling tower a installed outdoors, a cooling water low-temperature water tank b and a cooling water high-temperature water tank c near the cooling tower a, and a cooling water low-temperature water tank b And a pump f for returning the cooling water in the cooling water high-temperature water tank c to the cooling tower a, and the like.

That is, the cooling water in the cooling water low-temperature water tank b is supplied to a temperature controller d via a pipe n by driving a pump e, and the cooling water is supplied to a mold m from the temperature controller d. The mold m
Temperature is adjusted. The cooling water in the cooling water low-temperature water tank b is also supplied to the injection molding machine g via the pipe p, and the injection molding machine g is cooled by the cooling water. In FIG. 6, q is a water supply pipe, r is a drain pipe, s is a pipe for supplying cooling water to the cooling tower a via the pump f, and t is a pipe for supplying cooling water from the cooling tower a to the water tank b. A pipe u is a pipe for returning the cooling water.

Further, as shown in FIG.
Is equipped with a chiller h (chiller). In this case, cooling water is supplied from the pump e to the chiller h via the pipe v, and a cooling medium (cooling water) cooled by the chiller h is supplied to the temperature controller d via the pipe w. As in FIG. 6, the mold m and the injection molding machine g are cooled. In FIG. 7, x is a pipe for cooling water return, and y is a pipe for supplying water to the chiller h.

In the production of plastic molded products, it is necessary to set an optimum mold temperature in accordance with the shape of the product, the type of resin, the production cycle, and the like, and to constantly control the temperature at a constant level. Therefore, as described above, a temperature controller is used for the plastic molding apparatus. And the conventional temperature controller d
There are an indirect type shown in FIG. 8 and a direct type shown in FIG. The indirect type shown in FIG.
1, a heater 102 provided in the medium tank 101,
A cooler 103 provided in the medium tank 101, a liquid level controller 104, and a pump 105 for supplying a cooling medium (cooling water) in the medium tank 101 to the mold m are provided.

That is, the cooling water inlet 106 is connected to the medium tank 101.
Cooling water is supplied to the cooler 103
From the cooling water outlet 107 through the cooling water outlet 107. When the temperature of the medium in the medium tank 101 decreases, the temperature of the medium in the medium tank 101 is increased by the heater 102.
For this reason, the medium in the medium tank 101 whose temperature is controlled is
The mold m is circulated by the pump 105 and returns to the medium tank 101. At this time, the liquid level 108 of the medium in the medium tank 101 is controlled by the liquid level controller 104, and a constant liquid level position is maintained.

[0008] A temperature controller d shown in FIG.
101, a heater 102, and a liquid level controller 104,
As in the case of the temperature controller d shown in FIG. 8, the medium in the medium tank 101 circulates through the mold m to cool the mold m.

[0009]

Therefore, conventionally, a large amount of cooling water is required as a heat medium. Therefore, clogging due to water scale, corrosion due to deterioration of water quality, rust inside the mold, heat exchange rate due to generation of microorganisms are required. Failures such as a decrease in In addition, it is necessary to install a water tank, a cooling tower, and the like outside the room, which requires a large scale as a whole, and therefore requires a large space in the factory. Therefore, in the present invention, the use of the cooling water can be significantly reduced as compared with the conventional one, and the occurrence of each of the above-mentioned troubles can be effectively prevented, and further, the entire equipment can be simplified. An object of the present invention is to provide a cooling mechanism and a cooling method for a plastic molding apparatus that can be used.

[0010]

In order to achieve the above object, a cooling mechanism for a plastic molding apparatus according to the present invention is provided by circulating a medium through the plastic molding apparatus in a room where the plastic molding apparatus is installed. An indoor unit for cooling the plastic molding apparatus is installed, and an outdoor unit for cooling a medium of the indoor unit by circulating a cooling medium other than water in the indoor unit is arranged outside the room. is there.

[0011] The cooling mechanism of another plastic molding apparatus is as follows.
In a room where a plurality of plastic molding devices are installed, an indoor unit for cooling the plastic molding device by circulating a medium through the plastic molding device is installed corresponding to each plastic molding device, and outside the room, One outdoor unit is provided in communication with each indoor unit and circulates a cooling medium other than water through each indoor unit to cool the medium in each indoor unit.

[0012] The cooling mechanism of another plastic molding apparatus is as follows.
A cooling mechanism for a plastic molding apparatus having a temperature controller for controlling the temperature of a mold, wherein a medium supplied from the temperature controller to control the temperature of the mold is a cooling medium other than water. .

Further, according to the method of cooling a plastic molding apparatus according to the present invention, a medium is supplied to the plastic molding apparatus in an indoor unit in which the plastic molding apparatus is installed, and the plastic molding apparatus is cooled. A method for cooling a plastic molding apparatus, comprising: using a chemical coolant having rust-proof and anti-corrosion properties as a medium supplied to the plastic molding apparatus; and cooling water other than water from an outdoor unit installed outdoors. A medium is supplied to the indoor unit to cool the medium in the indoor unit.

[0014]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows a cooling mechanism according to the present invention. The cooling mechanism comprises a plurality of plastic molding apparatuses 1 in a room S.
And an indoor unit 2 disposed in the indoor S and an outdoor unit 3 disposed in the outdoor O.

The plastic molding apparatus 1 includes, for example, an injection molding machine 4 and a mold 5 to which a plastic molten material from the injection molding machine 4 is supplied. A temperature controller 6 for adjusting the temperature of the mold 5 is provided.

As shown in FIG. 2, the outdoor unit 3 includes a compressor 8, a condenser 9, a liquid receiver 10, an accumulator 11, and the like. Chemical coolant) tank 13 and the heat medium tank
An evaporator 14, a cooling water circulating pump 15, an expansion valve 16, and the like are provided inside 13.

That is, the compressor 8 and the condenser 9 are communicatively connected by a high-pressure gas pipe 17, and are connected to the receiver 10 by a high-pressure liquid pipe 18.
is connected to the expansion valve 16, and the high-pressure liquid pipe 18 b is connected to the expansion valve 16. The high-pressure liquid pipes 18 a and 18 b are connected to each other via the connection pipe 19. Also, the evaporator 14 has a connecting pipe
20 are connected and connected, and this connecting pipe 20 is connected to the accumulator
The accumulator 11 and the compressor 8 are connected to each other through a communication pipe 22. Further, a chilled water return pipe 23 is communicatively connected to the upper portion of the heat medium tank 13, and a chilled water outward pipe 24 is communicatively connected to the circulation pump 15. The connecting pipes 19 and 20 are external pipes disposed between the indoor unit 2 and the outdoor unit 3 as shown in FIG.

Accordingly, the gas of the cooling medium (for example, HCFC (R22) or HCF (R134a)) from the accumulator 11 enters the compressor 8 through the communication pipe 22, and the compressor 8
The compressed gas enters the condenser 9, where it is condensed and becomes a liquid and enters the receiver 10. From the receiver 10, a high-pressure liquid pipe 18 a, a connecting pipe 19, a high-pressure liquid pipe 18 b, And into the evaporator 14 via the expansion valve 16, where the heat medium tank
The heat is taken away by the medium 13 (cooling this medium), and the medium returns to the compressor 8 again via the connection pipe 20 and the communication pipe 21.
This cycle is repeated.

Then, a medium is supplied from the cold water outward pipe 24 to each of the molding devices 1..., Each of the molding devices 1 is cooled by the medium, and then cooled from each of the molding devices 1. The heated medium returns to the heat medium tank 13 of the indoor unit 2 via the cold water return pipe 23. In addition,
In FIG. 1, reference numeral 25 denotes a water supply pipe for supplying water to the indoor unit 2.

The medium in the tank 13 is a chemical coolant as described above, and the chemical coolant is a chemical agent required for rust prevention and corrosion prevention (for example,
Organic carboxylate, quaternary ammonium salt, etc.), which can effectively prevent the molding apparatus 1 from generating rust.

Thus, the medium is supplied to the injection molding machine 4 and the temperature controller 6. As the temperature controller 6, the one shown in FIG. 3 is used. That is, the temperature controller 6 includes a medium tank 26, a heater 27 and a cooler 28 provided in the medium tank 26.
And a medium pump 29 that is connected to the medium tank 26 via a pipe 40, a liquid level controller 30, and the like. The medium tank 26 and the like are housed in the casing C.

A coolant supply pipe 31 and a coolant discharge pipe 32 are connected to the cooler 28 so as to communicate with each other.
A heat medium supply pipe with an electromagnetic valve 33 is connected in communication. Further, the liquid level controller 30 and the medium tank 26 are connected to each other through a communication pipe 35, and the liquid level controller 30 is connected to a heating medium discharge pipe 36. The refrigerant supply pipe 31 has an electromagnetic valve 37
And an expansion valve 38.

The medium pump 29 and the mold 5 are connected to each other through a medium feed pipe 39, and the mold 5 and the medium tank 26 are connected to each other through a medium return pipe 41. In addition, the medium feeding pipe 39
And the return pipe 41 are connected by a bypass pipe 43 having a valve 42. Further, a sensor 44 is provided near the outlet of the medium pump 29 in the medium feeding pipe 39, and a sensor 45 is provided near the bypass pipe 43 in the medium returning pipe 41.

That is, in response to an instruction from the liquid level controller 30, the solenoid valve
33 is supplied to the medium tank 26 by controlling the medium. And
When measuring the temperature with the sensor 44 and cooling the medium,
A cooling medium is supplied from a refrigerant supply pipe 31 to the cooler 28 under reduced pressure to cool the medium in the medium tank 26. When heating the medium, the heater 27 in the tank 26 is energized to increase the temperature. As described above, by controlling the temperature of the medium in the medium tank 26, a medium having a temperature optimal for mold temperature control can be supplied to the mold 5. As a medium of the medium tank 26, for example, an ethylene glycol aqueous solution, a propylene glycol aqueous solution, or the like is used.

Next, a method of cooling the plastic molding apparatus using the cooling mechanism configured as described above will be described. That is, a medium (the medium is cooled by the cooling medium of the outdoor unit 3) is supplied from the indoor unit 2 to the temperature controller 6 through the pipe 24, and the temperature of the medium in the temperature controller 6 is increased. The temperature of the mold 5 is adjusted by circulating the medium through the mold 5 while controlling the temperature. Also, pipes 24 from indoor unit 3
The medium is circulated to the injection molding machine 4 through the, and the injection molding machine 4 is cooled.

Therefore, as a cooling method, a medium is supplied to the plastic molding apparatus 1 by the indoor unit 2 in the room S in which the plastic molding apparatus 1 is installed, and the plastic molding apparatus 1 is cooled. In this case, a cooling medium other than water is supplied from the outdoor unit 3 installed in the outdoor unit O to the indoor unit 2 to cool the medium in the indoor unit 2. For this reason, a large amount of water is not required as compared with the conventional one, and a trouble (for example, clogging due to water scale) due to the use of water can be effectively prevented, and each injection molding machine 4. In addition to being cooled well, the temperature of each of the molds 5 can be reliably adjusted, and a highly accurate product can be formed.

Next, FIG. 4 shows a modification of the temperature controller 6, in this case, a cooling medium tank 46, a cooler 47 provided in the cooling medium tank 46, a heating medium tank 48, and a heating medium tank 48. A heater 49 provided in the tank 48, a liquid level controller 50 for controlling the liquid level of the medium in the cooling medium tank 46, and a cooling pump 51 for supplying the medium in the cooling medium tank 46 to the injection molding machine 4. And a temperature control pump 52 for supplying the medium in the heating medium tank 48 to the mold 5. Also in this case, the cooling medium tank 46 and the like are housed in the casing C.

The cooler 47 has a refrigerant supply pipe 55 having a refrigerant solenoid valve 53 and a refrigerant expansion valve 54, and a refrigerant discharge pipe 56.
And the liquid level controller 50 and the medium tank 46 are connected by a communication pipe 57, and the liquid level controller 50 is connected by a heat medium discharge pipe 58. Further, the pump 52 and the heating medium tank 48 are communicated and connected by a pipe 59, and the pump 52
The mold 52 and the mold 5 are connected to each other through a medium supply pipe 60, and the mold 5 and the heating medium tank 48 are connected to each other through a medium return pipe 61. The medium sending pipe 60 and the return medium pipe 61 are connected to each other via a bypass pipe 63 having a valve 62, and the medium sending pipe 60 and the return medium pipe 61 are provided with sensors 64 and 65, respectively. .

The pump 51 is connected to the cooling medium tank 46 via a pipe 66 so that the pump 51 and the injection molding machine 4 are connected.
Are connected through a supply pipe 67, and the injection molding machine 4 and the cooling medium tank 46 are connected through a discharge pipe 68.
The heating medium tank 48 and the supply pipe 67 are connected to a cooling solenoid valve 69.
Are connected by a connection pipe 70 having Further, a medium discharge pipe 72 having an electromagnetic valve 71 is connected to the cooling medium tank 46, and the cooling medium tank 46 and the heating medium tank 48 are connected to each other through a communication pipe 73. 76 are provided. In FIG. 4, reference numeral 74 denotes an oil cooler.

Therefore, the medium in the cooling medium tank 46 cooled by the cooler 47 circulates through the injection molding machine 4 to cool the injection molding machine 4, and the temperature of the mold 5 is adjusted (temperature controlled). The controlled medium is circulated, and the mold 5 is controlled to an appropriate temperature. That is, also in this case, the medium is supplied to the plastic molding apparatus 1 by the indoor unit 2 in the room S in which the plastic molding apparatus 1 is installed, and the plastic molding apparatus 1 is cooled. A cooling medium other than water is supplied from the outdoor unit 3 installed in the outdoor unit O to the indoor unit 2 to cool the medium in the indoor unit 2.

FIG. 5 shows a cooling mechanism of another plastic molding apparatus. In this case, an indoor unit 2 is provided corresponding to a plurality of plastic molding apparatuses. The structure of each indoor unit 2 and outdoor unit 3 is shown in FIG.
, And a detailed description thereof is omitted, but a pair of chilled water outgoing pipes 24 and chilled water return pipes 23 are connected from each indoor unit 2.

In this case as well, a cooling medium other than water is supplied from the outdoor unit 3 installed outdoors to each of the indoor units 2 installed indoors, and a cooling medium (cooling water) for the indoor units 2 is provided. Cooling can be performed, thereby cooling each plastic molding apparatus.

The cooling mechanism of the plastic molding apparatus according to the present invention can surely cool each plastic molding apparatus without being affected by the number of plastic molding apparatuses installed indoors. Meanwhile, in plastic molding, it is necessary to cool the mold so as to remove heat from the molten resin injected into the mold 5 and solidify it, and to cool the cylinder and the resin input hopper 75.
In order to prevent the resin from dissolving due to heat conduction in the lower portion of the lower portion (see FIG. 1 and the like), it is necessary to effectively cool the lower portion of the resin input hopper 75.

[0035]

Since the present invention is configured as described above,
The following effects are obtained.

According to the first or second aspect, since a cooling medium other than water is used as a medium for cooling the plastic molding apparatus, clogging with scale is caused between the outdoor unit 3 and the indoor unit 2. Corrosion from poor water quality,
In addition, it is possible to prevent a decrease in heat exchange efficiency due to the generation of microorganisms, and to exhibit a stable cooling function over a long period of time. Further, it is not necessary to install a water tank and a cooling tower in the outdoor O, so that the structure as a whole can be simplified, and it is not necessary to take a large space in the factory for this mechanism, and the space in the factory is not required. Can be effectively used, and furthermore, the power for transporting the cooling water can be reduced, and the cost of piping can be reduced. In particular, according to claim 2, a more stable cooling function can be exhibited.

According to the third aspect, it is possible to effectively avoid water damage to the mold 5 (for example, generation of rust inside the mold 5), and to improve the cooling efficiency.

According to the fourth aspect of the present invention, the safety of the plastic molding apparatus (plastic system) including the mold 5 is controlled and obstacles (clogging due to water scale, corrosion due to deterioration of water quality, rust inside the mold, microorganisms) (Reduction in heat exchange efficiency due to generation) can be effectively prevented.

Furthermore, according to the fourth aspect, in a factory in an area where the temperature falls to 0 ° C. or less in winter, when the operation is stopped for a long time (for example, during New Year holidays) or when the plant is constructed in a cold area. In the factory, the water inside is frozen and the molding machine
Piping equipment may be damaged. At present, the water inside the apparatus is discharged to the outside during long-term leave or the water heated by an electric heater or the like is circulated during the suspension period to avoid breakage.
These problems can be avoided by using a chemical coolant as a cooling medium.

[Brief description of the drawings]

FIG. 1 is a simplified diagram of a cooling mechanism of a plastic molding apparatus according to the present invention.

FIG. 2 is a simplified diagram of an indoor unit and an outdoor unit.

FIG. 3 is a simplified diagram of a temperature controller.

FIG. 4 is a simplified diagram of another temperature controller.

FIG. 5 is a simplified view of a cooling mechanism of another plastic molding apparatus.

FIG. 6 is a simplified view of a cooling mechanism of a conventional plastic molding apparatus.

FIG. 7 is a simplified view of a cooling mechanism of another conventional plastic molding apparatus.

FIG. 8 is a simplified diagram of a conventional temperature controller.

FIG. 9 is a simplified diagram of another conventional temperature controller.

[Explanation of symbols]

 Reference Signs List 1 plastic molding apparatus 2 indoor unit 3 outdoor unit 5 mold 6 temperature controller O outdoor S indoor

Claims (4)

[Claims] 1. An indoor unit 2 for cooling a plastic molding apparatus 1 by circulating a medium through the plastic molding apparatus 1 is installed in a room S in which the plastic molding apparatus 1 is installed. A cooling mechanism for a plastic molding apparatus, comprising an outdoor unit 3 for circulating a cooling medium other than water in the indoor unit 2 to cool the medium in the indoor unit 2. 2. An indoor unit 2 for cooling a plastic molding apparatus 1 by circulating a medium through the plastic molding apparatus 1 in a room S in which a plurality of plastic molding apparatuses 1 are installed. 1 and an outdoor unit 3 for cooling the medium of each indoor unit 2 by circulating a cooling medium other than water through the indoor unit 2 and communicating with the indoor unit 2 to the outdoor O. A cooling mechanism for a plastic molding apparatus, wherein one is disposed. 3. A cooling mechanism for a plastic molding apparatus provided with a temperature controller 6 for controlling the temperature of a mold 5.
A cooling mechanism for a plastic molding apparatus, wherein a medium supplied from the control unit for controlling the temperature of the mold 5 is a cooling medium other than water. 4. A medium is supplied to the plastic molding apparatus 1 by an indoor unit 2 in the room S in which the plastic molding apparatus 1 is installed.
A method of cooling a plastic molding apparatus for cooling
As a medium supplied to the plastic molding apparatus 1,
A chemical medium having rustproof and anticorrosive properties is used, and a cooling medium other than water is supplied from the outdoor unit 3 installed in the outdoor O to the indoor unit 2 to cool the medium in the indoor unit 2. A method for cooling a plastic molding apparatus, comprising: