JPH0564364B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a temperature adjustment device suitable for use in adjusting the temperature of molds used in injection molding, die casting, and the like.

(Prior art) Generally, a temperature adjustment device that adjusts the temperature of a mold, etc. by circulating temperature-adjusted water in the circulation path of a temperature-controlled object, such as a mold, uses a heater or the like installed in a tank to heat the object. This method heats and circulates the water, but it can be divided into two types of cooling methods. One is a direct cooling method in which cooling water is mixed into the tank and the same amount of temperature-controlled water as the supplied cooling water is discharged, and the other is in a heat exchanger installed in the tank. This is an indirect cooling method in which cooling water is passed through the

(Problems to be Solved by the Invention) In the temperature adjustment device using the above-mentioned direct cooling method, cooling water is directly mixed into the tank. is rapidly cooled to a predetermined temperature, has a large cooling capacity, and has good response. However, if the temperature difference between the return temperature-adjusted water and the cooling water is large, the cooling capacity is large, resulting in large temperature variations and poor control accuracy.

In addition, in temperature adjustment devices using indirect cooling method,
Since the cooling speed is slow (responsiveness is slow), control accuracy is better than the direct cooling method when the temperature difference between the return temperature control water and the cooling water is large, but the temperature difference between the return temperature control water and the cooling water is small. In some cases, there is a problem that temperature control becomes impossible.

For this reason, as a cooling method, either a direct cooling method or an indirect cooling method is adopted in consideration of the temperature difference between the return temperature controlled water and the cooling water.

(Means for Solving the Problems) In view of the above circumstances, the present invention realizes a temperature regulating device with good cooling accuracy regardless of the temperature difference between return temperature regulating water and cooling water. It comprises the configuration shown.

In other words, the temperature of the object to be temperature controlled is controlled by circulating temperature-controlled water, whose temperature is adjusted to an arbitrary set temperature by heating by a heating means and cooling by mixing cooling water, into the passage of the object to be temperature-controlled, such as a mold. In a temperature control device that performs temperature adjustment, a supply path that supplies temperature-controlled water in a tank having a heating means to a temperature-controlled object using a pump, and a return path that guides temperature-controlled water returned from the temperature-controlled object into the tank. a temperature sensor that detects the temperature of the temperature-controlled water in the supply path; a cooling path that supplies cooling water from the water pressure source to the return path or into the tank; In order to discharge a portion of the adjusted water, a drainage channel connected to a drainage outlet, a solenoid valve interposed in the drainage channel, and a cooling channel partially inserted into the temperature-controlled water in the drainage channel or return channel. a heat exchange unit that exchanges heat between the temperature-controlled water and the cooling water; and a temperature detection signal from the temperature sensor is input, and based on the temperature, the solenoid valve is driven to open and close the drain channel. and a controller that supplies the cooling water to the return path or into the tank.

(effect) Next, the operation of this invention will be described.

When the temperature of the temperature-controlled water in the circulation path rises, the solenoid valve is opened by the action of the controller, and the temperature-controlled water is discharged from the drainage path, and the cooling water in the cooling path is supplied to the return path or tank. In addition, the cooling water is
Heat is exchanged in the heat exchange section, reducing the temperature difference between the temperature-controlled water and the cooling water.

The amount of heat exchanged in the heat exchange section is determined by the temperature difference between the cooling water and the temperature control water, and when this temperature difference is large, the amount of heat exchanged is large, and when this temperature difference is small, the amount of heat exchanged is small. Therefore, when the temperature difference is large, the cooling water warms up and it is possible to adjust the temperature variation of the temperature control water. Moreover, when the temperature difference is small, the cooling water hardly exchanges heat and mixes to cool the temperature-controlled water.

(Embodiments) Hereinafter, preferred embodiments of the present invention will be described in detail based on the accompanying drawings.

[First Embodiment] The general reference numeral 10 is a temperature adjustment device of the present invention.

20 is a mold which is a temperature controlled body. This mold 20
A temperature control circuit (not shown) is provided inside the temperature control circuit (not shown), and a temperature control water pump 2 is connected to the inlet of this temperature control circuit (not shown).
2 is connected to one end of the supply path 18, and the other end of the supply path 18 is connected to the tank 12 having a heater 14 as a heating means. On the other hand, one end of a return path 24 is connected to an outlet of a temperature control circuit (not shown) of the mold 20, and the other end of the return path 24 is connected to the tank 12. The supply path 18 and the return path 24 constitute a circulation path 40 that supplies temperature-controlled water to the mold 20. In addition, heater 1
4 is connected to the controller 16.

Further, a temperature sensor 26 is provided immediately before the pump 22 and is connected to the controller 16.

A cooling path 28 for supplying cooling water is connected to the return path 24 immediately before the heating section 12, and cooling water is appropriately pressurized and supplied to the cooling path 28 at a constant pressure from a water pressure source. Further, a discharge passage 30 is provided for discharging the temperature-controlled water in the tank 12 from a drain port. A tank-shaped storage section 30 is provided in the middle of the discharge path 30.
Temperature-controlled water to be discharged after forming the storage section 30a is temporarily stored, and a midway portion of the cooling path 28 is inserted into this storage section 30a, thereby forming a heat exchange section 32. Further, a solenoid valve 34 is provided at the tip of the discharge path 30, and this solenoid valve 34
is connected to the controller 16, and the controller 1
The discharge passage 30 is opened and closed by the signal from 6.

Further, the controller 16 is connected to a temperature setting device (not shown), and also includes a temperature sensor 26, a pump 22, a heater 14, and a solenoid valve 34.
is under control.

Next, the operation of the temperature adjusting device having the above configuration will be described.

A predetermined temperature is set on a temperature setting device (not shown). Then, the cooling path 28 and the circulation path 40 are connected,
Cooling water fills the circulation path 40 . Then, the heater 14 is energized to raise the water temperature in the tank 12, and the pump 22 is activated. In this case, since the solenoid valve 34 is in the closed position, the cooling water flows through the circulation path 4.
After being filled with water, the temperature-controlled water does not flow in and is balanced with the pressure in the circulation path 40, and the temperature-controlled water circulates through the supply path 18, the mold 20, and the return path 24.

Then, as the temperature-controlled water heated by the heater 14 circulates, the temperature of the mold 20 increases accordingly.
Until a predetermined temperature is reached, the mold 20 steals the temperature of the temperature control water and raises the temperature. Therefore, the return temperature controlled water is cooled, but when it reaches a predetermined temperature, the return temperature controlled water is
Then, the temperature only decreases by the amount of heat dissipated by the mold 20.
When the temperature sensor 26 detects that the temperature of the temperature-adjusted water has reached a predetermined temperature, a signal is generated from the comparator in the controller 16, and the power to the heater 14 is cut off.

Then, molding begins.

When molding is started, molten resin is injected and filled into the mold 20, so the temperature of the circulating temperature-controlled water increases. When the temperature sensor 26 detects that the water temperature has become higher than the set value, a signal from the controller 16 causes the solenoid valve 34 to open.

Then, the temperature control water is discharged and the pressure in the circulation path 40 decreases, so the pressure of the cooling water is overcome, and the same amount of cooling water as the discharged amount is supplied to the return path 24 and mixed in the return path 24. The temperature of the temperature-controlled water drops.

Then, when the temperature of the temperature-controlled water detected by the temperature sensor 26 matches the set value, the solenoid valve 34 is closed to operate in a closed state.

Thereafter, the controller 16 controls the opening and closing of the solenoid valve 34 to control the temperature.

Note that the cooling water flows through the return path 2 via the heat exchange section 32.
4, heat is exchanged between the temperature control water and the cooling water discharged at the heat exchange section 32. The amount of heat exchanged indirectly at this time is determined by the temperature difference between the cooling water and the temperature-controlled water, and when the temperature difference is large, the amount of heat exchanged is large, and when the temperature difference is small, the amount of heat exchanged is small.

Therefore, when the set temperature is low and the temperature difference with the cooling water is small, the cooling water is mixed into the return path 24 without being heated by heat exchange, and the temperature of the temperature-adjusted water is quickly lowered. In addition, if the set temperature is high and the temperature difference between the cooling water and the cooling water is large, the cooling water will be heated to a certain temperature by heat exchange and mixed into the return path 24, so there will be a temperature difference between the temperature controlled water and the cooling water. becomes smaller, reducing temperature fluctuations and allowing more accurate control.

[Second Embodiment] FIG. 2 shows the configuration of a temperature adjustment device according to a second embodiment.

In the second embodiment, the discharge path 30 branches off from the middle of the return path 24, and the cooling path 28 is connected between this branch and the tank 12. Other configurations are the first
The structure is similar to that of the embodiment, and the same functions and effects are achieved.

In this embodiment, the discharge path 30 is replaced by the return path 24.
Since the temperature-adjusted water is provided just before the confluence of the cooling path 28 and the temperature-adjusted water is discharged before being mixed with the cooling water, the heat exchange efficiency in the heat exchange section 32 is excellent.

[Third Embodiment] FIG. 3 shows the configuration of a temperature adjustment device according to a third embodiment.

In the third embodiment, a storage section 2 is provided in the middle of the return path 24.
4a is provided, and a heat exchange section 32 is formed by passing an intermediate portion of the cooling path 28 through the storage section 24a.
A discharge path 30 is branched from the middle of the return path 24 from the heat exchange section 32 to the tank 12, and a cooling path 28 is connected immediately before the tank 12. The other configurations are the same as those of the first embodiment, and the same operations and effects are achieved.

In addition, in this embodiment, heat exchange is performed between the total temperature controlled water in the return path 24 and the cooling water, so that the heat exchange efficiency is even more excellent.

In addition, although the cooling path was connected to the return path in each of the above embodiments, the cooling water may be supplied to the tank.

(Effects of the Invention) In the present invention, as described above, by implementing a simple method of exchanging heat between the cooling water supplied to the return path and the temperature-controlled water to be discharged, the return temperature-controlled water and the cooling water can be exchanged. It is possible to obtain a temperature adjusting device that has little temperature variation and high control accuracy even when the temperature difference between the two is large, and can perform temperature control even when the temperature difference is small.

Therefore, a single temperature adjustment device can control temperatures from low to high temperatures with high accuracy and high response, reducing equipment costs, and the device itself can be manufactured compactly, lightweight, and inexpensively, resulting in fewer failures.

[Brief explanation of the drawing]

FIGS. 1 to 3 are schematic explanatory diagrams showing the configuration of a temperature adjusting device showing a preferred embodiment of the present invention. 10... Temperature adjustment device, 12... Tank, 14
... Heater, 16 ... Controller, 20 ... Mold, 26 ... Temperature sensor, 32 ... Heat exchange section, 3
4... Solenoid valve.

Claims (1)

[Scope of Claims] 1 Temperature-controlled water whose temperature is controlled to an arbitrary set temperature by heating by a heating means and cooling by mixing cooling water is circulated in a passage of a temperature-controlled object such as a mold to be heated. In a temperature control device that controls the temperature of a temperature-controlled object, there is a supply path for supplying temperature-controlled water in a tank with a heating means to a temperature-controlled object using a pump, and a tank for returning temperature-controlled water from the temperature-controlled object. a temperature sensor that detects the temperature of the temperature-controlled water in the supply path; and a cooling path that supplies cooling water from the water pressure source to the return path or the tank. , a drainage channel connected to a drain port for discharging a portion of the temperature-controlled water in the circulation channel; a solenoid valve installed in the drain channel; a heat exchange section that partially passes through a cooling path and exchanges heat between the temperature-controlled water and the cooling water; and a temperature detection signal from the temperature sensor is input, and the solenoid valve is driven based on the temperature. and a controller that opens and closes the drainage channel to supply cooling water to a return channel or into a tank.