JPH0643065B2 - Mold temperature controller with automatic temperature control medium recovery function - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial field of application) The present invention is to automatically provide a medium for temperature adjustment from a mold when an abnormality occurs in an operating power supply in a mold device provided with a temperature controller. The present invention relates to a mold temperature control device having a recovery function.

(Prior Art) The temperature at which a heat exchange medium for temperature adjustment is circulated in a mold in order to adjust the mold temperature to a desired predetermined temperature in a mold device or the like that injects a plastic resin for molding. Adjustment devices are known.

Conventional devices are roughly classified into those that pump the medium to the mold device and those that suck the medium.

FIG. 2 is a schematic view showing a conventional temperature control device, which is capable of pumping or sucking a medium into a mold device,
The flow direction of the pumping operation is shown by a solid line, and the flow direction of the negative pressure (suction) operation is shown by a dashed arrow.

Since this switching can be easily performed by changing the rotation direction of the pump 205, a description will be given of the case of using this device for medium pressure feeding, and a description of suction will be omitted.

The mold temperature control device 200 is sold separately, and the medium outlet 230 and the medium return port 231 of this device are connected to a passage provided in a mold device (not shown).

The medium tank 202 having the capacity number is filled with the medium 203 from the medium injection port 222.

The level of the medium is monitored by the float 213 and is replenished by the automatic medium feeding system so that the medium is constantly filled with a substantially constant amount.

204 is a drain. Since water is used as the medium in this embodiment, the medium is injected from the cooling water inlet 220 through the filter 223 and the electromagnetic valve 241 for automatic medium feeding as will be described later.

The heat dissipation control of the temperature of the medium is performed by the heat exchanger 211.

From the cooling water inlet 220 to the heat exchanger 211, the filter 2
23, cooling water is injected through the cooling solenoid valve 242, and is discharged from the cooling water outlet 221. Medium 2 in medium tank 202
A heating wire heater 212 having a capacity of several KW is inserted in the unit 03 to control heat absorption to the medium.

Control of these temperatures is performed by the well-known PID control method.

The medium 203 by the pump 205 arranged in the medium
Is pressure-fed to a cooling passage of a mold (not shown) through the medium outlet 230, and the medium circulated in the cooling passage is returned to the medium return port 23.
Returned from 1.

(Problems to be Solved by the Invention) In recent years, as the precision and miniaturization of the above-described molding die apparatus has progressed, the need for precise temperature management has increased. For this purpose, a cooling medium passage is provided in the mold, and the medium is circulated from an external device, which is the conventional example described above, to control the temperature.

However, the packing etc. for preventing the leakage of the medium cannot be used sufficiently, an abnormal state is formed in the mold due to power down, etc., and if the medium remains in the mold, the medium will be It may intrude into an unintended part to stain the inside of the mold or flow out from the mold. Therefore, it is necessary to collect the medium that has been circulating through the flow path in the mold whenever such inconvenience occurs (power down).

In such a case, in a conventional device (for example, a device as shown in FIG. 2), the medium outlet 230 is normally blocked and a compressor (not shown) or pressurized air is shown in the flow path on the mold side of the blocked portion. Not pump to the mold cooling passage.

Then, the medium pushed by the pressurized air and circulating in the cooling passage is recovered from the medium return port 231. According to this configuration, most of the medium can be collected, but since pressure is applied to the medium, if there is a gap in the medium flow path or if there is an incomplete seal, the medium will enter the mold more than that. Leakage may damage the inside of the mold.

Also, if it flows out from the mold, it may damage the environment.

It is an object of the present invention to provide a mold temperature control device having a temperature control medium automatic recovery function that automatically recovers a medium without applying pressure when an abnormality occurs in the power supply of the device.

(Means and Actions for Solving the Problems) In order to achieve the above object, a mold temperature controller having a temperature control medium automatic recovery function according to the present invention is a mold that circulates a medium by supplying and circulating the medium into a mold flow path. A mold temperature adjusting device for controlling the temperature of a medium tank, a pump arranged in the medium of the medium tank, and a medium supply channel connecting the medium tank and the inlet of the in-mold channel. A supply passage electromagnetic valve provided in the medium supply passage, a medium return passage connecting an outlet of the in-mold passage and an inlet of the pump, and a medium return passage A return flow path solenoid valve, a recovery flow path that connects the inlet of the mold flow path and the suction port of the pump, an air tank provided in the recovery flow path, and connects the air tank and the pump Flow from the pump to the air tank in the recovery channel A check valve provided in a blocking direction, a recovery passage electromagnetic valve provided in a passage between the air tank and the inlet of the in-mold passage, the return passage opening / closing solenoid valve, and the return passage opening / closing solenoid valve An outside-air introducing solenoid valve that opens and closes to introduce outside air into the reflux passage at the outlet of the flow path in the mold, a pressure sensor that detects pressure reduction in the air tank and outputs pressure information, and troubles that occur in the device The defect sensor for detecting, and the supply passage solenoid valve, the recovery passage solenoid valve, and the return passage solenoid valve are closed at the time of start-up, the pump is started, the pressure in the tank is reduced, and the supply flow is made by the signal of the pressure sensor. Control circuit that opens the return passage solenoid valve and the return passage solenoid valve to recirculate the medium, closes the supply passage solenoid valve and the return passage solenoid valve according to the output of the defect sensor, and opens the recovery passage solenoid valve outside air introduction solenoid valve. Has been done.

The medium may be water, and the mold may be an injection mold.

The detection target of the defect sensor is a voltage drop, and the supply passage solenoid valve and the return passage solenoid valve are normally-closed solenoid valves, which themselves detect and close the voltage drop. The valve is a normally open solenoid valve, which itself detects the voltage drop and opens, and by itself acting as the sensor having a defect detection function, the control circuit can be constructed very simply.

At this time, the control circuit can completely recover the medium without the backup of the power supply.

(Example) Hereinafter, the present invention will be described in more detail with reference to the drawings.

FIG. 1 is a wiring diagram showing an embodiment in which a mold temperature adjusting device according to the present invention is connected to a mold device.

The mold temperature control device 100 is connected to both ends of the in-mold passage 51 formed in the mold 50 by the flow paths 40 and 41.
The medium is sucked into the in-mold passage 51 from the flow passage 40,
Taken out from 1.

The single solid arrow attached to the flow path indicates the moving direction of the medium in the normal state, and the double arrow indicates the collecting direction. Mold passage 5
When it is desired to regain the medium from No. 1, the air is sucked from the flow channel 41 and the medium is regained from the flow channel 40.

This embodiment also uses water as a medium, and the replenishment of the medium 3 into the medium tank 1 and the adjustment of the temperature of the medium in the tank are substantially the same as those of the conventional apparatus described above, and therefore the description thereof is omitted.

A pump 5 for suction is provided inside the medium tank 1.

The suction port (I) of the flow path 30 is inserted into the medium 3 of the medium tank 1.

The medium flowing in the flow path 30 is connected to the flow path 51 in the mold 50 via the filter 15 and the electromagnetic valve 11 and the flow path 40 connecting the mold temperature adjusting device 100 and the mold 50.

(Flow channel 30 → flow channel 39 → flow channel 40) forms a medium supply flow channel.

The outlet end (O) of the flow path 51 in the mold 50 is connected to the filter 17 of the mold temperature control apparatus 100 via the flow path 41 that connects the mold 50 and the mold temperature control apparatus 100.

The filter 17 is connected to the flow channel 31, and the flow channel 31 is connected to the flow channel 32 via the electromagnetic valve 14. Channel 3
2 is connected to a pump 5 in the medium 3.

(Flow path 41 → flow path 31 → flow path 32) forms a medium return path.

A flow path 33 for introducing outside air is provided in the flow path 51 in the mold 50 when the medium is collected, and the control valve 21 and one of the flow paths 33 are connected to the outside air. A solenoid valve 13 is provided. A branch flow path 34 is further connected to the flow path 32, and the flow path 35, the tank 9, and the flow path 3 are further connected.
6, the solenoid valve 12, the control valve 20, and the filter 16 are the medium tank I
The filters 16 are connected in this order from the side, and the filter 16 is connected to the flow path 40.

(Flow channel 40 → flow channel 36) forms a medium recovery flow channel.

The pressure in the flow path 36, that is, the tank 9 can be constantly monitored by the vacuum gauge 23.

In addition, a pressure switch 24 that operates when the pressure in this portion reaches a certain negative pressure is provided in each channel 36.

The control circuit 10 is configured so that the solenoid valves 11 and 14 are driven by the information of the pressure switch 24.

The solenoid valves 11 and 14 are kept closed until the tank 9 is depressurized to a constant pressure. Control circuit 10
The pressure information from the pressure switch 24, the voltage information indicating the state of the power supply voltage, other information and commands (starting command by turning on the switch), commands indicating the operating state of the pump, etc. Based on that, the solenoid valve 11,
An instruction is issued to 12, 13, 14, etc.

When the control circuit 10 is started, the supply passage solenoid valve 11, the recovery passage solenoid valve 12, the outside air introduction solenoid valve 13, the return passage solenoid valve 1
4 is closed and the pump 5 is started. When the pressure in the tank 5 is reduced and the signal of the pressure sensor 24 is generated,
The control circuit 10 opens the supply passage solenoid valve 11 and the return passage solenoid valve 14 to recirculate the medium.

By the output of the defect sensor (voltage information in this embodiment), the supply passage solenoid valve 11 and the return passage solenoid valve 14 are closed,
The recovery passage solenoid valve 12 and the outside air introduction solenoid valve 13 are opened.

In this embodiment, the detection target of the defect sensor is a voltage drop, and known detection means, for example, voltage drop detection means in the current path may be used.

In this embodiment, the solenoid valve itself is provided with a function as a defect sensor.

The supply passage solenoid valve 11 and the return passage solenoid valve 14 are normally-open solenoid valves, which themselves detect the voltage drop and close a part of a control circuit, and also have a function as a defect sensor and an actuator.

The recovery passage solenoid valve 12 and the outside air introduction solenoid valve 13 are normally-open solenoid valves, which themselves detect and open the voltage drop, and similarly have a part of the control circuit and functions as a defect sensor and an actuator. .

(Explanation of Operation) In the normal operation, the pump 5 moves the medium 3 through the flow path 30.
Is sucked from the inlet (I) of the mold 50 and supplied to the flow path 51 of the mold 50 through the bonding flow path 40, and after the temperature of the mold 50 is adjusted, the flow path is returned to the apparatus through the bonding flow path 41. It returns to the tank 1 from the flow path outlet (O) of the flow path 32 via 31.

Starting solenoid valve 11, solenoid valve 12, solenoid valve 14, solenoid valve 1
3 is closed and the pump 5 is rotated to reduce the pressure in the tank 9.

When the pressure in the tank 9 reaches the degree of vacuum set in the pressure switch 24, the solenoid valve 11 and the solenoid valve 14 open to operate as the normal device.

During normal operation, the depressurized pressure in the tank 9 is kept depressurized by the check valve 7 and the electromagnetic valve 12.

When a power source abnormality occurs, the solenoid valves 11 and 14 are automatically closed, the solenoid valves 12 and 13 are opened, and the medium remaining in the flow path (R) 51 of the mold 50 is sucked by the negative pressure in the tank 9. Collected in the tank 9. At this time, the solenoid valve 13 is opened to enhance the recovery efficiency, and the recovery of the medium is measured by the difference in the atmospheric pressure.

Further, the medium collected in the tank 9 is used for the next start-up tank 9
When the pressure is reduced, it is collected in the system through the check valve 7.

(Effects of the Invention) As described in detail above, the apparatus according to the present invention is a mold temperature adjusting apparatus that supplies and circulates a medium to the flow path in the mold to adjust the temperature of the mold, and has the above-mentioned configuration. The supply passage solenoid valve, the recovery passage solenoid valve, and the return passage solenoid valve are closed at the time of start-up, the pump is started, the pressure in the tank is reduced, and the supply passage solenoid valve is reduced by a signal from the pressure sensor. Open the return path solenoid valve to recirculate the medium, close the supply channel solenoid valve and the return channel solenoid valve according to the output of the defect sensor, open the recovery channel solenoid valve and the outside air introducing solenoid valve, and automatically recover the temperature control medium. can do.

Although it has an extremely simple structure, it is capable of qualifying measures such as power down.

[Brief description of drawings]

FIG. 1 is a wiring diagram showing an embodiment in which a mold temperature adjusting device according to the present invention is connected to a mold device. FIG. 2 is a wiring diagram showing a conventional mold temperature adjusting device. 1 ... Medium tank, 3 ... Medium 5 ... Pump, 7 ... Check valve 9 ... Air tank 10 ... Control device 11 ... Supply flow path solenoid valve 12 ... Recovery flow path solenoid valve 13 ... Outside air introducing solenoid valve 14 ...... Return path solenoid valve 15, 16, 17 …… Filter 20, 21 …… Adjusting valve 23 …… Vacuum gauge, 24 …… Pressure switch (pressure sensor) 30, 31, 32, 33, 35 ...... Flow path 40, 41 ...... Flow path 50 ...... Mold, 51 ...... Mold flow path 100 ...... Mold temperature control device 200 ...... Mold temperature control device (conventional example) 201 ...... Medium tank , 203 ... medium 204 ... drain, 205 ... pump 211 ... heat exchanger, 212 ... heater 213 ... float (float) 220 ... cooling water inlet, 221 ... cooling water outlet 222 ... medium injection Inlet 230 …… Medium outlet (medium return port) 231 …… Body Modokuchi (medium outlet) 241 ...... water supply electromagnetic valve 242 ...... medium cooling solenoid valve

Claims (1)

[Claims] 1. A mold temperature control device for controlling the temperature of a mold by supplying a medium to a flow path in the mold and circulating the medium, the medium tank, and a pump arranged in the medium of the medium tank. A medium supply channel connecting the medium tank and an inlet of the in-mold channel, a supply channel electromagnetic valve provided in the medium supply channel, an outlet of the in-mold channel and the pump A medium return path connecting the suction port of the medium, a return path solenoid valve provided in the medium return path, a recovery channel connecting the inlet of the in-mold channel and the suction port of the pump, and the recovery An air tank provided in the flow path, a check valve provided in a recovery flow path connecting the air tank and the pump in a direction for blocking a flow from the pump to the air tank, and the air Recovery channel provided in the channel between the tank and the inlet of the in-mold channel An electromagnetic valve, an electromagnetic valve for the return passage and an outside air introduction electromagnetic valve that opens and closes to introduce outside air into the return passage at the outlet of the flow path in the mold, and detects pressure reduction of the air tank and outputs pressure information. Pressure sensor, a defect sensor that detects an inconvenience that has occurred in the device, the supply passage solenoid valve, the recovery passage solenoid valve, and the return passage solenoid valve are closed at startup, the pump is activated, and the tank pressure is reduced. The supply flow path solenoid valve and the return flow path solenoid valve are opened by the signal of the pressure sensor to open the medium, and the supply flow path electromagnetic valve and the return flow path electromagnetic valve are closed by the output of the defect sensor. Mold temperature controller with temperature control medium automatic recovery function composed of control circuit for opening the outside air introduction solenoid valve.