JPH063339B2 - Control device of the temperature controller - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application This invention uses a cold-controlled brine (water or liquid) as a load for a plastic molding die or the like installed at a position distant from the main body of the apparatus. The present invention relates to a cooling and temperature adjusting device used to maintain a predetermined temperature.

(B) Conventional Technology The applicant has previously proposed, as this type of cooling and controlling apparatus, one shown in FIG. 5 (Japanese Patent Application No. 62-293239).

In FIG. 1, (A) is composed of a compressor (1), a condenser (2), a dryer (3), a capillary tube (4), an evaporator (5) and an accumulator (6) which are sequentially connected in an annular shape. The refrigerant circuit, (B), is a brine circulation path that circulates the brine in the liquid tank (7) to the load (9) such as a mold via the circulation pump (8). The liquid tank (7) is made of stainless steel with the top open, and the inside of the tank is divided into an upper brine chamber (7a) and a lower brine chamber (7b) by a partition plate (11) that has a liquid passage hole (10). Has been done. The evaporator (5) is immersed in the brine in the upper brine chamber (7a), and the heater (12) is inserted in the lower brine chamber (7b). Brine circuit (B) is a load
The forward flow path (13) and the return flow path (1) between the (9) and the liquid tank (7).
4), and the return flow path (14) is branched into two branch paths (14a) (14b) on the inlet side of the liquid tank (7). And
One branch (14a) is connected to the upper brine chamber (7a),
The other branch (14b) is connected to the lower brine chamber (7b). In addition, by making the pipe diameter of the branch passage (14b) larger than the pipe diameter of the branch chamber (14a), and providing a resistor (15) in the branch passage (14b), the upper brine chamber (7a) and the lower brine chamber (7a) Brine room
The amount of brine flowing into (7b) is adjusted appropriately. In addition, these return passages (14a) (14b) upstream of the return flow path (1
4) has an inlet (16a) and a first outlet (16b) of the three-way switching valve (16).
And a flow path for an air-cooled heat exchanger having an air-cooled heat exchanger (18) between the second inlet (16c) of the three-way switching valve (16) and both branch passages (14a) and (14b). Road (19) is connected. Also,
(20) is a bypass pipe connected in parallel with the air-cooled heat exchanger (18) and having a resistor (21), (23) is a fan, (24) is a control device, and air of the fan (23) A condenser (2) and an air-cooled heat exchanger (18) are juxtaposed in the passage.

The control device (24) has a temperature sensor (25) for detecting the brine temperature of the return flow path (14) and a room temperature sensor (26),
(1), the circulation pump (8), the heater (12), the three-way switching valve (16) and the fan (23) are controlled.

In the above conventional apparatus, the brine temperature is changed from 15 ° C to 50 ° C.
When keeping the temperature up to ℃, the controller (24)
(1), the circulation pump (8) and the fan (23) are operated, and the three-way switching valve (16) is switched as shown by arrow a. Also,
The heater (12) is turned on according to the temperature detected by the temperature sensor (25),
Linearly controls the turn-off time. Therefore, the brine cooled in the upper brine chamber (7a) and the lower brine chamber (7b)
In the lower brine chamber (7b), the brine heated in (1) joins and becomes a brine having a predetermined temperature, which is sent to the load (9) via the outward flow path (13). The load (9) brine is returned to the return channel (1
It returns to the upper brine chamber (7a) and the lower brine chamber (7b) via 4) and the branch passages (14a) and (14b). In this way, the brine in the liquid tank (7) is circulated and supplied to the load (9), and the load temperature is maintained near a predetermined temperature (15 to 50 ° C.).

When the brine temperature is maintained at a predetermined temperature from 50 ° C to 90 ° C, the control device (24) stops the compressor (1), operates the circulation pump (8) and the fan (23), and operates the three-way switching valve ( Switch 16) as shown by arrow B. In addition, the temperature sensor (2
The ON / OFF energization time of the heater (12) is linearly controlled according to the temperature detected in 5). Furthermore, the rotation speed of the fan (23) is controlled according to the temperature difference between the temperature detected by the temperature sensor (25) and the room temperature sensor (26), and the rotation speed of the fan (23) is reduced when the temperature difference is large. Also, when the temperature difference is small, the fan (23)
Increase the rotation speed of. Therefore, the brine flowing out of the liquid tank (7) is the outflow passage (13) -the load (9) -the three-way switching valve (16) -the air-cooling type heat exchanger passage (19) and the bypass pipe (20).
− The temperature of the brine supplied to the load (9) by flowing in the order of the branch paths (14a) and (14b) and returning to the liquid tank (7) depends on the heat radiation amount in the air-cooled heat exchanger (18) and the heater (12). The temperature is maintained at a predetermined temperature (50 to 90 ° C.) depending on the heating amount of).

(C) Problem to be Solved by the Invention In the above-described conventional apparatus, since the liquid tank is open to the atmosphere, brine evaporates during use and the liquid level in the liquid tank decreases. Therefore, a liquid level detector is installed in the liquid tank,
When the liquid level drops below the set liquid level, the liquid supply device is operated to replenish the brine, and when the liquid level further drops, the compressor and the circulation pump are stopped to protect the device. However, since the brine of the liquid tank is circulated to the load by the circulation pump, the liquid level of the liquid tank fluctuates up and down, and the liquid supply device, the compressor and the circulation pump frequently start and stop near the set liquid level. was there.

It is made in view of the above-mentioned fact of the present invention,
Prevent frequent start and stop of the liquid supply device, compressor, and circulation pump when the liquid level is near the set liquid level, and also to promptly supply brine when the liquid tank has no brine. The purpose is to do.

(D) Means for Solving the Problems In the present invention, a refrigerant circuit in which a compressor, a condenser, a decompression device and an evaporator are connected, a liquid tank in which the evaporator of this refrigerant circuit is immersed in brine, and a circulation A liquid level detector for detecting the liquid level of a liquid tank, and a liquid tank, in a cooling and temperature adjusting device comprising a brine circulation path having a pump and circulating brine as a load, and a liquid supply device for supplying liquid to a liquid tank. Means for activating the liquid supply device when the liquid level is below the first set liquid level for the first predetermined time, and a second lower than the first set liquid level.
And a means for operating the compressor and the circulation pump when the liquid level equal to or higher than the set liquid level continues for the second predetermined time.

Further, according to the present invention, in the above-described control device for the cooling and temperature adjusting device, there is provided a means for inhibiting the delay operation of the means for operating the liquid supply device when the liquid level in the liquid tank is lower than the second set liquid level.

(E) Operation When the liquid level in the working liquid tank falls below the first set liquid level due to evaporation of brine or the like, the first timer (means) causes the water supply device to operate with a predetermined delay. Therefore, when the liquid level of the liquid tank moves up and down near the first set liquid level, the water supply device can be prevented from operating, and frequent start / stop of the water supply device can be prevented. Further, when the liquid level in the liquid tank is lowered due to some abnormality and becomes lower than the second set liquid level, the compressor and the circulation pump are stopped to protect them. At this time, even if the liquid level moves up and down near the second set liquid level,
The function of the timer (means) can prevent the compressor and the circulation pump from operating immediately and prevent them from being frequently started and stopped.

Furthermore, when the liquid level of the liquid tank is lower than the second set liquid level, a means for inhibiting the delay operation of the first timer (means) for activating the liquid supply device is provided so that the liquid tank can be used as in the initial use. When there is no brine, the brine is quickly supplied.

(F) Examples Hereinafter, examples of the present invention shown in the drawings will be described.

FIG. 1 shows an example of a temperature control device to which the present invention is applied. In FIG. 1, the same parts as those shown in FIG. 5 are designated by the same reference numerals.

In the cooling and temperature controller shown in FIG. 1, a liquid supply pipe (27) is connected to the upper part of the liquid tank (7), and a solenoid valve (28) is connected to the liquid supply pipe (27).
Has been inserted. A liquid level detector (29) is provided in the upper part of the liquid tank (7).

The liquid level detector (29) is, as shown in FIG. 2, loosely fitted on a support rod (32) having two reed switches (30) and (31) built therein, and the support rod (32). , Consists of a pair of upper and lower floats (35) (36) whose downward movement is restricted by stoppers (33) (34), and magnets (37) (38) are attached to the floats (35) (36), respectively.
Is embedded.

FIG. 3 shows a schematic configuration of the control device (24). In FIG. 3, (39) is a power switch, (40) is a control unit, and relay contacts (411) (421) (431) (441) that are opened and closed according to the output signal of this control unit (40). ...... by solenoid valve (28),
The energization of the compressor (1), the circulation pump (8), etc. is controlled.

As shown in FIG. 4, the control unit (40) has two timers (4
5) (46) is built in. First timer (45) is resistance (47)
(48) and reed switch (30), inverter (49), resistor (5
0) (51), diode (52) and capacitor (53), NAND circuit (54), resistors (55) (56) (57), inverter (58), resistor
(59) (60), a transistor (61), and a relay (41) for opening and closing a relay contact (411). Also, the second
The timer (46) has a resistor (62) (63) and a reed switch (31).
An inverter (64), a resistor (65) (66), a diode (67) and a capacitor (68), a NAND circuit (69), and a resistor (70) (71)
An inverter (72), a resistor (73) (74) and a transistor (75)
And a relay (42) for opening and closing the relay contact (421). Further, the input side of the inverter (58) of the first timer (45) and the output side of the NAND circuit (69) are connected by a latch circuit (inhibiting means) (77) having a diode (76).

When the liquid tank (7) is empty as in the initial use, the floats (35) (36) of the liquid level detector (29) are in the state shown in Fig. 2 and the reed switches (30) (31) Are closed together. When the power switch (39) is turned on, the input of the inverter (64) becomes "L" in the second timer (46), and its "H" output becomes the resistance (6
Since it is input to the NAND circuit (67) via 6) and the diode (67), the output of the NAND circuit (69) becomes "L". At this time, the output of the inverter (72) becomes "H" and the transistor
(75) turns on and relay (42) is energized. Therefore, the relay contact (421) opens and the compressor (1) and circulation pump
(8) There is no driving. Meanwhile, the first timer (45)
Then, the output of the inverter (49) is "H", and the capacitor (53) is charged through the resistor (50). Therefore, the output of the NAND circuit (54) remains "H" until a predetermined time has passed, but the input side of the inverter (58) is connected to the "N" of the NAND circuit (69) via the latch circuit (77). Since the L "output is supplied, the output of the inverter (58) becomes" H ", the transistor (61) is turned on, and the relay (41) is excited. Then, the solenoid valve (28) is energized via the relay contact (411), the solenoid valve (28) is opened, and brine (eg, water) is supplied from the liquid supply pipe (27) into the liquid tank (7). .

When the liquid level in the liquid tank (7) rises to reach or exceed the second set liquid level L2, the float (36) rises and the reed switch (31)
Opens. At this time, the output of the inverter (64) becomes “L” in the second timer (46), and the capacitor (68) is charged through the resistor (65) and the internal circuit of the inverter (64). Because
The potential of one input terminal of the NAND circuit (69) gradually decreases. Then, when a predetermined time elapses from the time when the reed switch (31) is turned off, the output of the NAND circuit (69) becomes "H" and the transistor (75) is turned off. At this time, the excitation of the relay (42) is released and the relay contact (421) is closed, so that the compressor (1), the circulation pump (8) and the like start operation. In this way, the liquid level in the liquid tank (7) rises and L
When it becomes 1 or more, the compressor (1) and the circulation pump (8) are operated with a delay for a predetermined time, so that the liquid level of the liquid tank (7) moves up and down by the operation of the circulation pump (8). Even if it operates, there is no concern that the compressor (1), the circulation pump (8), etc. will frequently start and stop. Further, when the output of the NAND circuit (69) becomes "H", the latch circuit (77) releases the latch, but before that, the output of the NAND circuit (54) becomes "L". 61) remains on, and liquid supply to the liquid tank (7) is continued.

When the liquid level in the liquid tank (7) exceeds the first set liquid level L1,
The reed switch (30) opens, and the output of the inverter (49) becomes "L" in the first timer (45). At this time, the capacitor (5
The charge of 3) is quickly discharged through the diode (52) and the resistor (51), and the output of the NAND circuit (54) becomes "H". Therefore, the transistor (61) is turned off, the excitation of the relay (41) is released, the solenoid valve (28) is closed, and the supply of brine is completed.

The brine evaporates during use and the liquid level in the liquid tank (7) becomes L.
When it becomes 1 or less, the reed switch (30) is closed. However, in the first timer (45), the relay (41) is not immediately excited even when the reed switch (30) is closed, so the liquid level of the liquid tank (7) moves up and down by the operation of the circulation pump (8). , Even if the reed switch (30) is repeatedly opened and closed, the solenoid valve (2
8) does not repeat opening and closing. And capacitors (53)
When the battery is sufficiently charged, the relay (41) is excited, the solenoid valve (28) is opened, and the liquid supply is started.

When the liquid level further decreases due to liquid leakage or the like and becomes L2 or less, the reed switch (31) is closed, the second timer (46) promptly excites the relay (42), and the compressor (1) and the electromagnetic pump ( 8) etc. will stop. In this case, even if the reed switch (31) repeatedly opens and closes due to the vertical movement of the liquid level, it takes time to charge the capacitor 68, so the relay (42) remains excited and the compressor (1) and the electromagnetic pump (8) etc. do not repeat starting and stopping, and these can be protected.

(G) Effect of the Invention Since the present invention is configured as described above, the liquid level is set when the liquid level of the liquid tank is lowered due to evaporation of brine, or when the liquid level is further lowered due to liquid leakage or the like. Even if it moves up and down in the vicinity of the liquid level, it is possible to prevent the liquid supply device, the compressor, and the circulation pump from being repeatedly started and stopped, and to protect them.

Further, by providing a means for prohibiting the delay operation of the first timer when the liquid level of the liquid tank is lower than the second set liquid level, when the liquid tank does not have a brine as in the initial use, the brine supply is performed. It can be started quickly and is easy to use.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an example of a temperature control device to which the present invention is applied, FIG. 2 is a structural explanatory diagram of a liquid level detector, FIG. 3 is an electric circuit diagram showing an example of a control device, and FIG. FIG. 5 is an electric circuit diagram showing an internal configuration of a control unit of the control device, and FIG. 5 is a schematic configuration diagram of a conventional cooling / temperature adjusting device. (A) ... Refrigerant circuit, (1) ... Compressor, (2) ... Condenser, (4)
… Capillary tube (pressure reducing device), (5)… Evaporator,
(B) ... Brine circulator, (7) ... Liquid tank, (8) ...
Circulation pump, (9)… Load, (24)… Control device, (27)
... liquid supply pipe, (28) ... solenoid valve (liquid supply device), (29) ... liquid level detector, (45) ... first timer (means), (46) ... second
Timer (means), (77)… Latch circuit (prohibition means).

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Masafumi Okada 2-18, Keihan Hon-dori, Moriguchi City, Osaka Sanyo Electric Co., Ltd. (56) Reference JP-A-1-135603 (JP, A) -80305 (JP, U)

Claims (2)

[Claims] 1. A refrigerant circuit comprising a compressor, a condenser, a decompression device, and an evaporator, a liquid tank in which the evaporator of the refrigerant circuit is immersed in brine, and a circulation pump. In a cooling and temperature adjusting device including a brine circulation path that circulates in a liquid tank and a liquid supply device that supplies liquid to a liquid tank, a liquid level detector that detects the liquid level of the liquid tank, and the liquid level of the liquid tank is a first predetermined value. Means for operating the liquid supply device when the liquid level is below the first set liquid level for a period of time;
A controller for a cooling and temperature adjusting device, comprising: means for operating a compressor and a circulation pump when a liquid level equal to or higher than a set liquid level continues for a second predetermined time. 2. The cold temperature control according to claim 1, further comprising means for prohibiting a delay operation of means for operating the liquid supply device when the liquid level in the liquid tank is lower than the second set liquid level. The control device of the device.