JPH0546890Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) This invention is a device that adjusts the temperature of the mold by supplying a heat medium such as water or oil to the mold attached to a synthetic resin molding machine. More specifically, the present invention relates to a temperature control device for a mold that can control the temperature by creating a temperature difference between the core and cavity of the mold.

(Background of the idea) The temperature of the mold not only affects the quality of the molded product, but also affects the molding efficiency, and is an important control item in the molding process of synthetic resins. Temperature control must always be performed accurately.

Therefore, in general, both the core and cavity of the mold are cooled as uniformly as possible.
This prevents deformations such as warping and twisting from occurring in the molded product.

However, with some plastic molded products, if both the core and cavity of the mold are cooled uniformly as described above, deformations such as warpage and twisting may occur in the molded product. In this case, it is recognized that the above-mentioned deformation etc. can be eliminated by providing a temperature difference between the core and the cavity and cooling them.

(Prior Art) Conventionally, as a method of cooling a mold temperature in a low temperature range, a single unit refrigerator is used, which is equipped with at least one compressor, one condenser, one expansion valve, and one evaporator. Chilled water of the same temperature from the temperature-controlled cold water tank is supplied via the evaporator to each cold water passage in the core and cavity of the mold to cool the core and cavity at the same temperature, and the cooling water is transferred to the evaporator. A mold temperature control device with a refrigerator is known in which the mold temperature is returned to the container to form a circulation circuit. However, with this configuration consisting of a single refrigerator, it is not possible to cool the core and cavity of the mold at different temperatures.

Therefore, a configuration has been proposed in which two units of the above-mentioned refrigerators are used to adjust the cooling temperatures of the mold core and cavity at different temperatures.
In other words, two units of refrigerators each equipped with the necessary components for a refrigeration system such as a compressor, condenser, expansion valve, evaporator, and cold water tank are installed side by side, and the units are supplied from one unit. The cold water supplied from the mold core is passed through the cooling water passage of the mold core, and the cold water supplied from the other unit is passed through the cavity to create a temperature difference and cool the mold.

(Problem to be solved by the invention) However, since the above conventional example requires two units of the refrigerator (compressor, condenser, expansion valve, evaporator, etc.), the configuration of one unit is required. This method requires not only parts but also many other parts such as piping, which has the major problem of not only increasing installation costs but also requiring a large installation space.

This invention solves the above problem by using a simple structure with fewer components by sharing the compressor and condenser in one unit of refrigeration system and adding expansion valves and evaporators in any number of units. This is an attempt to resolve the issue.

(Means for Solving the Problems) This invention, as a means for solving the above problems, uses a single unit refrigerator that has at least one compressor, one condenser, one expansion valve, and one evaporator. In a mold temperature adjustment device for a synthetic resin molding machine, the mold temperature is adjusted by cooling the cooling water and passing the cooling water through a cold water passage of the mold to adjust the temperature of the mold. One or more branch refrigerant passages are provided at appropriate locations from the condenser to the evaporator in the refrigerant line that returns to the compressor via the refrigerant line, and each branch refrigerant passage is further provided with an expansion valve and an evaporator, respectively forming a cold water line from the cold water tank to the mold and returning to the evaporator, so that different cooling temperatures are obtained from each cold water line; The first cold water line among the plurality of cold water lines is connected to the cold water passage on either side of the mold core or cavity, and the second cold water line is connected to the cold water passage on the other side. It adopts a configuration in which the cooling temperatures of the core and cavity of the mold are different.

(Function) Since this device has the above configuration, it operates as follows.

A refrigerant consisting of a gas that easily evaporates and liquefies, such as ammonia or freon, is compressed by a compressor to become a high-temperature, high-pressure gas. The heat of this gas is removed by cooling water from a water supply source such as a cooling tower in a condenser, and the gas becomes a liquid that remains under high pressure. This liquid is subjected to water and moisture removal by the dryer shown in the embodiment, and then sent to the evaporator through the narrow passage of the expansion valve. At this time, the liquid is suddenly blown out from the narrow passage into the wide, low-pressure evaporator, so it vaporizes and expands to become a low-temperature gas.The gas is absorbed again into the low-pressure side of the compressor, while the evaporator It absorbs the heat of the liquid in the cold water tank connected to it and cools it. Since the action of this refrigerant line is repeated in circulation, the temperature of the liquid in the cold water tank can be cooled to a desired temperature.

The cold water in the cold water tank, which has been cooled by the evaporator as described above, is sent from the cold water outlet to the cold water passage of the mold by the discharge pressure of the circulation pump, removes heat from the mold, and returns to the cold water inlet. The returned cold water enters the evaporator, where it is cooled again and stored in the cold water tank. In other words, the action of the cold water line is repeated and repeated.

The mold is cooled as described above, but in this invention, one or more branch refrigerant passages are provided at appropriate locations in the refrigerant line from the condenser to the evaporator. At the same time, each of the branched refrigerant passages is further connected to another expansion valve and an evaporator, and each of the evaporators is provided with a cold water line that returns from the cold water tank to the evaporator via the mold, A different cooling temperature is obtained from each cold water line, and among the plurality of cold water lines, the first cold water line is connected to a cold water passage on either side of the mold core or cavity, and the second cold water line is connected to a cold water passage on either side of the mold core or cavity. Since it is connected to the cold water passage on the other side, the cooling temperatures of the core and cavity of the mold can be made different.

The temperature of the cooling water in each chilled water line is controlled, for example, by transmitting a signal from a temperature sensor attached to each chilled water line to a solenoid valve attached upstream of the expansion valve, and by transmitting a signal from a temperature sensor attached to the downstream side of the evaporator. By transmitting a signal to the expansion valve,
This may be done by controlling the flow rate of the refrigerant liquid to the evaporator. Further, the desired temperature of each cold water line may be set using a temperature controller connected to the temperature sensor.

(First Embodiment) A first embodiment of this invention will be described below based on FIGS. 1 and 2.

FIG. 1 is a process diagram showing the entire temperature regulating device for a mold for a synthetic resin molding machine of this invention, and FIG. 2 is a sectional view showing an example of the evaporator in FIG. 1.

A has one each of a compressor 1, a condenser 2, a dryer 3, a solenoid valve 4, an expansion valve 5, a first evaporator 6, and an accumulator 7, which are connected in sequence to form a refrigerant line. This is a one-unit refrigeration system.

Of the refrigerant line I that returns from the compressor 1 to the compressor 1 via the condenser 2, the expansion valve 5, the first evaporator 6, and the accumulator 7 of the one unit refrigeration system A, the first evaporator from the condenser 2 One or two or more (in the example, one
) branch refrigerant conduction passages 8... are provided. The branched refrigerant conduit 8 includes another expansion valve (second expansion valve in the embodiment) 15 that is separate from the expansion valve 5 and the first evaporator 6 used in the one unit refrigeration system A.
... and an evaporator (second evaporator in the embodiment) 16 are connected, respectively, and the second evaporator 16 is further connected to the accumulator 7. 14
is a solenoid valve provided separately from the solenoid valve 4.

That is, from the branch refrigerant passage 8 to the second electromagnetic valve 14, the second expansion valve 15, and the second evaporator 1.
6, accumulator 7, compressor 1, condenser 2,
The refrigerant line that returns to the branch refrigerant conduit 8 via the dryer 3 shares the line from the accumulator 7 to the compressor 1, condenser 2, and dryer 3.

Each of the evaporators (in this example, the first evaporator 6)
and the second evaporator 16), there is a cold water line that returns from the cold water tank (in this embodiment, the first cold water tank 20 and the second cold water tank 30) to the evaporators 6, 16, etc. through the mold 40. The cooling water lines are formed so that different cooling temperatures can be obtained from each cold water line. The setting control of the temperature difference of the cooling water in each cold water line Ha, N... is carried out as described above, between the evaporators 6, 16...
0, 30... or the temperature sensor (not shown) attached to the cold water tank 20, 30... to each electromagnetic valve 4, 14... and each evaporator 6, 1.
The flow rate of the refrigerant liquid to each evaporator 6, 16 may be controlled by transmitting the signal from the temperature sensor 9 installed downstream of 6 to each expansion valve 5, 15. The method may be selected as appropriate.

Each cold water tank 20, 30... has a water supply pipe 12 connected at its upstream end to a water supply source 10 such as a cooling tower or tap water, and at its downstream end to a branch water supply pipe 11, 11...
It depends on the distribution of water.

The water in the water supply source 10 is also sent to the condenser 2 through the inlet pipe 13a, where it absorbs heat from the refrigerant gas, raises the water temperature, and returns to the water supply source 10 via the outlet pipe 13b, where the water temperature is lowered to the original temperature again. In this way, a circulating cooling water line is constructed. However, the cooling water line is not limited to this, and of course may be of a one-time type.
17 and 18 are valves.

A valve 19 and a strainer 28 are attached to the upstream side of the water supply pipe 12. The tip side of the branch water supply pipe 11 connected to the water supply pipe 12 is the first cold water tank 2
0. Facing the second cold water tank 30..., ball taps 21, 31... are provided at the tips thereof, and when the ball taps 21, 31... are lower than a certain position, the valve attached to the branch water supply pipe 11 is installed. 22, 32... are opened to replenish the water supply, so that the water level in the cold water tanks 20, 30... is always maintained at a constant level. Drain pipes 23, 33 are provided at the bottom of the first cold water tank 20, the second cold water tank 30...
... and connect these drain pipes 23, 3.
3... is collected in one pipe and the drain is discharged outside the system. 24 is a valve.

Among the plurality of cold water lines described above, the first cold water line is connected to the cold water passage 43 or 4 on either side of the core 41 of the mold 40 or the cavity 42.
4, and the second cold water line 2 is connected to the cold water passage 44 or 43 on the other side, and is connected to the mold 4.
0 core 41 and cavity 42 are made to have different cooling temperatures. That is, the cold water supply path 25 from the first cold water tank 20 to the mold 40 in the first cold water line, and the cold water supply path 35 from the second cold water tank 30 to the mold 40 in the second cold water line. are circulation pumps 26 and 3, respectively.
6. Pressure gauges 27, 37 and valves 28, 38, which play the role of regulating the amount of cold water discharged, are installed. The tip of the cold water supply path 25 is connected to the cold water path 44 of the cavity 42 of the mold 40,
The tip of the cold water supply path 35 is connected to the cold water path 43 of the core 41 of the mold 40 . A cold water discharge passage 50 extends from the outlet of the cold water passage 44 of the cavity 42 to the first cold water tank 20 via the first evaporator 6, and from the outlet of the cold water passage 43 of the core 41 to the second evaporator 16. A cold water discharge path 51 extends to the second cold water tank 30 via the cold water discharge path 50,
Valves 52 and 53 are attached to appropriate positions of 51, and the cold water supply channels 25 and 35 and the cold water discharge channels 50 and 51 are connected through bypass pipes 54 and 55, and 56 and 57 are the bypass valves. be.

In this embodiment, the first and second evaporators 6, 16 have a U-shaped cooling pipe 61 installed horizontally in a body 60, and a large number of partition plates fixed by tie rods 62, as shown in the second figure. 63... is installed internally, and the refrigerant inlet 6
4 and a refrigerant outlet 65.
6 is connected by a flange to the opening of the body 60, 67 is a cold water inlet, 68 is a cold water outlet, 70 is a temperature regulator for freezing prevention, and 71 is a drain port. It goes without saying that the evaporators 6 and 16 are not limited to the configuration described above, and the design can be changed as appropriate.

In addition, 72 in FIG. 1 is a drain receiver.

(Second Embodiment) FIG. 3 shows a second embodiment. This product can be applied to two synthetic resin molding machines, and the tip of the cold water supply path 25 formed in the first cold water line in FIG. 1 is branched to form a first branch supply path. 25a is connected to the cold water passage 43 of the core 41 of the mold 40, and is connected to the second branch supply passage 25b.
is a cold water passage 44 in a cavity 42 of another mold 40.
On the other hand, a first branch discharge passage 50a communicating with the first branch supply passage 25a and a second branch discharge passage 50b communicating with the second branch supply passage 25b are connected to the cold water discharge passage 50. In this way, the tip of the cold water supply path 35 formed in the second cold water line is branched, and the first branch supply path 35a is connected to the mold 40.
The second branch supply passage 35b is connected to the cold water passage 44 of the cavity 42 of another mold 40, while the second branch supply passage 35b is connected to the cold water passage 43 of the core 41 of another mold 40.
A first branch discharge path 51 communicating with the branch supply path 35a
a and a second branch discharge passage 51b communicating with the second branch supply passage 35b are connected to the cold water discharge passage 51. In this way, two molds with different cooling temperatures can be used.
There are advantages that can be provided.

Note that the other configurations are the same as those shown in FIG.

In the embodiment, one branch refrigerant passage 8 is provided, but two or more branch refrigerant passages 8 may be provided, and a corresponding number of evaporators may be connected to supply cooling water to the mold from three or more locations. You can also do that.

(Effects of the Invention) This invention provides one or more branch refrigerant passages at appropriate locations from the condenser to the evaporator in a refrigerant line that runs from the compressor through the condenser, expansion valve, evaporator and back to the compressor, and each branch refrigerant passage is further connected to another expansion valve and evaporator, and each evaporator is provided with a cold water line that runs from a cold water tank through a mold and back to the evaporator, so that different cooling temperatures can be obtained from each cold water line, and a first of the multiple cold water lines is connected to the cold water passage on either side of the core or cavity of the mold, and a second cold water line is connected to the cold water passage on the other side, so that the cooling temperatures of the core and cavity of the mold are made different, and has the following effects.

In other words, by sharing the compressor and condenser in one unit of refrigeration equipment and simply adding new expansion valves, evaporators, and cold water tanks, the cold water passages in the mold core and cavity can have different cooling temperatures. Can be cooled by running cold water.

Moreover, unlike the conventional model, two units of the refrigerator (compressor, condenser, expansion valve, evaporator, etc.) are not required, but the components of one unit include a new expansion valve, evaporator, and cold water tank. Since it is only necessary to add a refrigeration system, the number of components, piping, etc. for the refrigeration system can be reduced, and the installation cost is not only low, but also the installation space can be significantly reduced.

[Brief explanation of the drawing]

Each figure shows an embodiment of this invention. FIG. 1 is a process diagram of the first embodiment, FIG. 2 is a sectional view showing an example of the condenser shown in FIG. 1, and FIG. 3 is a process diagram of the second embodiment. A, B...Refrigerant line, C, D...Cold water line, E...Cooling water line, 1...Compressor, 2...
Condenser, 3... Dryer, 4, 14... Solenoid valve, 5, 15... Expansion valve, 6... (first) evaporator, 7... Accumulator, 8... Branch refrigerant conduit, 10... ...Water supply source, 11...Branch water supply pipe, 1
2... Water supply pipe, 16... (Second) evaporator, 20
...first cold water tank, 25...cold water supply path, 26,
36...Circulation pump, 30...Second cold water tank, 4
0... Mold, 41... Core, 42... Cavity, 43... Core cold water passage, 44... Cavity cold water passage, 50, 51... Cold water discharge passage.

Claims (1)

[Claims for Utility Model Registration] (1) A liquid is cooled by one unit of refrigerator having at least one compressor, one condenser, one expansion valve, and one evaporator, and this cooling water is passed through the cold water passage of the mold. In a mold temperature adjustment device for a synthetic resin molding machine, the refrigerant line returns from the compressor to the compressor via a condenser, an expansion valve, and an evaporator. One or more branch refrigerant passages are provided at appropriate locations from the container to the evaporator, and each branch refrigerant passage is further connected to another expansion valve and an evaporator, Each of the evaporators is provided with a cold water line that returns from the cold water tank to the evaporator through the mold, so that different cooling temperatures are obtained from each cold water line, and a first cold water line among the plurality of cold water lines is formed. is connected to the cold water passage on either side of the mold core or cavity, and the second cold water line is connected to the cold water passage on the other side, so that the cooling temperatures of the mold core and cavity are different. A temperature control device for a mold for a synthetic resin molding machine, characterized in that: (2) Each of the cold water tanks is configured to distribute water through a water supply pipe connected to a water supply source at the upstream end and a branch water supply pipe at the downstream end. Temperature control device for molds for synthetic resin molding machines. (3) A dryer is provided between the condenser and the expansion valve, and an accumulator is provided between the evaporator and the compressor, respectively.Scope of Utility Model Registration Claims (1) or (2) A temperature control device for a mold for a synthetic resin molding machine as described above.