JPH0332717B2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Industrial Application Field The present invention relates to an ice maker that removes ice that has grown on the inner wall of a cooling cylinder with an ice cutting auger and sends it out. This invention relates to a protection device for an ice maker that stops its operation.

(b) Prior art For example, Japanese Patent Publication No. 56-40258 discloses a method in which one or more through holes are formed in the radial direction of an ice delivery member in which the axial position of a rotating screw blade in a cooling cylinder is fixed. An auger-type ice maker is disclosed in which an ice detection device is provided above the ice sending member, the ice detection device detects ice passing through the through hole, and the ice making operation is stopped.

(c) Problems to be Solved by the Invention In the above-mentioned conventional technology, when shaved ice accumulates in the ice delivery chamber provided at the top of the cooling cylinder, the shaved ice that is successively pushed up into the ice delivery chamber is removed from the delivery member. The ice is also pushed upward through the through hole, activating the ice detection device and stopping the ice making operation. When the ice pressed upward from the through hole melts, the ice detection device becomes inactive and ice making operation is started. However,
When the ice-making operation is started, if the accumulation of shaved ice in the ice delivery chamber is not eliminated, the shaved ice is again pressed upward through the through hole, the ice detection device is activated, and the ice-making operation is stopped. Thereafter, when the ice pushed upward through the through hole melts, if the accumulation of shaved ice has not been resolved, the ice making operation is stopped, and the ice making operation is started and stopped at short time intervals, This causes problems in that the drive mechanism of the auger device may fail and the service life of the drive mechanism is shortened.

(d) Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides a cooling cylinder having a passageway for refrigerant fed under pressure from an electric compressor of a refrigeration system on its outer surface, and a cooling cylinder. In an ice maker equipped with an internally rotating ice-shaving auger and an auger motor that drives the ice-shaving auger, supercooling detects ice clogging based on a temperature drop in the cooling cylinder and stops the ice-making operation. a temperature detection circuit, an overload current detection circuit that stops the ice making operation based on the overload current of the auger motor, and an overload current detection circuit that operates when the ice making operation is stopped due to the operation of the supercooling temperature detection circuit or the overload current detection circuit. A timer device that outputs an output after a predetermined time after the start, and a timer device that maintains the stoppage of the ice-making operation after the ice-making operation is stopped by the operation of the supercooling temperature detection circuit or overload current detection circuit, and when the timer device outputs the A protection device for an ice making machine is provided, which includes a holding circuit that starts ice making operation when a supercooling temperature detection circuit and an overload current detection circuit do not detect supercooling or overload.

(E) Effect When ice clogging occurs in the ice maker, the supercooling detection circuit or overload current detection circuit detects the ice clogging and operates, and the ice making operation is stopped. The timer device starts operating when the ice-making operation stops, and thereafter outputs an output at predetermined intervals. When the cooling detection circuit and the overload current detection circuit detect that the ice blockage has been cleared, the stoppage of the ice-making operation is canceled and the ice-making operation is started.

(F) Embodiment Hereinafter, an embodiment of the present invention will be described in detail based on FIGS. 1 to 3.

FIG. 3 is a system diagram of an auger-type ice maker embodying the present invention, in which 1 is a cooling cylinder, and the outer surface of this cooling cylinder 1 has a condenser 4, etc., which is forcedly air-cooled by an electric compressor 2 and a blower 3. An evaporation pipe 5, which together forms a refrigerant circuit, is wound around it. Also, cooling cylinder 1
An ice cutting auger 6 is rotatably supported inside by an upper bearing 7 and a lower bearing 8. This ice-shaving auger 6 is connected to an auger motor 10 via a speed reducer 9, scrapes off ice grown on the inner surface of the cooling cylinder 1, and transfers it to a plurality of compression passages 11 formed on the outer periphery of the upper bearing 7. The compressed and hardened ice is discharged from a discharge cylinder 12 connected to the upper part of the cooling cylinder 1.

A water storage tank 13 determines the water supply level of the cooling cylinder 1, and the bottom of the tank 13 and the lower part of the cooling cylinder 1 are connected to each other by a water supply pipe 14. 15 is a water pipe that supplies water to the water storage tank 13;
Water level detection device 1 that detects the water level of the water storage tank 13
A water supply valve 17 controlled by 6 is connected thereto. Here, the water level detection device 16 adopts a float method in which a reed switch in the pipe is opened and closed by a magnet-incorporated float 16A that rises and falls according to changes in the water level, and the upper reed switch 16B controls the opening and closing of the water supply valve 17. and lower read switch 1
6C is used for detecting water outage. Further, 18 is a drain pipe connected to the lower part of the cooling cylinder 1, and is equipped with a drain valve 19 for opening and closing the pipe.

Next, a protection circuit and an operation circuit according to the present invention will be explained based on FIGS. 1 and 2.

Reference numeral 20 in FIG. 1 is a supercooling temperature detection circuit (hereinafter referred to as supercooling detection circuit), to which a temperature sensor 29 attached to the outlet side of the evaporation pipe 5 is connected.
It is connected to the input terminal of the holding circuit 21. or,
22 is an overload current detection circuit, and a current detection circuit 24 provided in a power supply line 23 to the auger motor 10 is connected to this overload current detection circuit 22, and is connected to a second holding circuit 25. Furthermore, 26, 27, and 28 are an OR circuit, a first NOR circuit, and a second NOR circuit, and these circuits 26, 2
A first holding circuit 21 is connected to one input terminal of 7 and 28.
output terminal is connected, and the other input terminal is connected to the second output terminal.
The output terminal of the holding circuit 25 is connected. Here, the output terminal of the OR circuit 26 is connected to the base of a first transistor 31 that controls energization of the third relay coil 30 via a resistor _R1 , and the output terminal of the first NOR circuit 27 is connected to a resistor _R2. It is connected to the base of a second transistor 33 that controls energization of the fourth relay coil 32 via. Further, the second NOR circuit 28 is connected to the output control terminals of the first and second holding circuits 21 and 25 via a timer device 35 including an oscillation circuit 35A and a counter circuit 35B.

2, 40 is a power switch, 41 is a first relay connected in series to the upper reed switch 16B, and normally closed first relay switches 41A and 41B.
has. Note that a water supply valve 17 is connected in series to the first relay switch 41B. Further, 42 is a first relay switch 41 connected to the lower read switch 16C.
The second relay is connected in series through A and has a normally open second relay switch 42A and a normally closed second relay switch 42B. Furthermore, 30S is a normally open third relay coil that is turned on when the third relay coil 30 is energized.
A relay switch, connected to the drain valve 19, and 3
2S is a normally open fourth relay switch that is turned on when the fourth relay coil 32 is energized;
It is connected to the blower 3 and the auger motor 10.

The operation of the ice maker will be explained below. First, when the water storage tank 13 is empty, the upper reed switch 16B is off and the lower reed switch 16C is on, and when the power switch 40 is turned on, the water supply valve 17 is opened via the normally closed first relay switch 41B. When energized, it opens and the water storage tank 13
Water supply will begin. Further, the second relay 42 is energized, the normally closed second relay switch 42B is turned off, and the electric compressor 2, blower 3, and auger motor 10 are de-energized and no ice-making operation is performed.

The water supply tank 13 and cooling cylinder 1
The water level in the tank gradually rises, and when it reaches a predetermined water level, the upper reed switch 16B is turned on and the first relay 41 is turned on.
is energized, and the first relay switches 41A, 41B
are both turned off, the water supply valve 17 is de-energized and the water supply is stopped, and the normally open second relay switch 42A is turned off.
and turn on the normally closed second relay switch 42B. Here, when ice making operation has not been performed and there is no ice clogging, etc., both the supercooling detection circuit 20 and the overload current detection circuit 22 output a low level signal (hereinafter referred to as L signal). ,
The second holding circuits 21 and 25 both input the L signal and output the L signal, and the OR circuit 26 and the first and second
Each input terminal of the NOR circuits 27 and 28 receives an L signal. Then, the OR circuit 26 outputs an L signal, the first transistor 31 is off, and the third relay coil 30 is de-energized, so the third relay switch 30 is turned off.
S is off and the drain valve 19 is closed. Further, the first NOR circuit 27 outputs a high level signal (hereinafter referred to as H signal), the second transistor 33 is turned on and the fourth relay coil 32 is energized, and the fourth relay switch 32S is turned on and the electric compressor is turned on. 2. The blower 3 and the auger motor 10 are energized and start operating. Further, the second NOR circuit 28 outputs an H signal, and at this time, the oscillation circuit 35A of the timer device 35
does not oscillate, the timer device 35 outputs an H signal, the reset terminals of the first and second holding circuits 21 and 25 both input this H signal, and continuously output an L signal.

When the ice making operation is performed as described above, ice clogging occurs in the cooling cylinder 1 or the discharge cylinder 12, and as the cooling load decreases, the temperature of the refrigerant flowing out from the evaporation pipe 5 also decreases to a predetermined level. When the temperature reaches
The overcooling detection circuit 20 outputs an H signal instead of the L signal, and the first holding circuit 21, which has received this H signal, outputs an H signal. And the OR circuit path 26 is H
A signal is output to the first transistor 31, and this first
When the transistor 31 is turned on, the third relay coil 30 is energized, the third relay switch 30S is turned on, the drain valve 19 is energized and opened, and the cold water in the cooling cylinder 1 is drained. When the first water level switch 16B is turned on due to a drop in the water level in the water storage tank 13, the water supply valve 17 is opened and water is supplied. Also, due to the H level signal output of the first holding circuit 21, the first
The NOR circuit 27 outputs an L level signal, the second transistor 33 is turned off, the fourth relay coil 32 is de-energized, the fourth relay switch 32S is turned off, and the electric compressor 2, blower 3, and auger motor 10 are turned off. The operation is stopped and the ice making operation is stopped. Further, in response to the H level signal output from the first holding circuit 21, the second NOR circuit 28 outputs an L level signal, and the oscillation circuit 35A of the timer device 35 starts oscillating.
Counter circuit 35B starts counting.

Further, when a large load is applied to the ice cutting auger 6 due to ice clogging in the cooling cylinder 1 and an overcurrent flows to the auger motor 10, the current detection section 24 detects the current, and the overload current detection circuit 22 detects the current. An H signal is output based on the current detection by the detection unit 24, and the second holding circuit 25, which has received this H signal, outputs an H signal. When the second holding circuit 25 outputs the H signal, the other input terminals of the OR circuit 26, the first NOR circuit 27, and the second NOR circuit 28 input the H signal, and the respective circuits 26, 27, and 28 outputs the L signal to detect the above ice blockage from the overcooling detection circuit 2.
0 is detected, the drain valve 19 opens,
The cold water in the cooling cylinder 1 is drained, the ice making operation is stopped, and the timer device starts operating.

As described above, after the ice making operation is stopped due to the operation of the supercooling detection circuit 20 or the overload current detection circuit 22, the drain valve 19 is opened while the timer device is counting, and the inside of the cooling cylinder 1 is When the cold water and the water in the water storage tank 13 decrease, the first water level switch 16B is turned on and water is supplied to the water storage tank 13, and the water level gradually rises and the first water level switch 16B is turned on.
Water supply is stopped by turning off B, and thereafter, the first water level switch 16B is repeatedly turned on and off, and the cold water in the cooling cylinder 1 is replaced with the tap water in the water storage tank 13. Then, as the ice-making operation is stopped and the cold water in the cooling cylinder 1 is drained, the ice blockage gradually loosens, and the temperatures of the cooling cylinder 1 and the evaporation pipe 5 gradually rise, for example, the ice-making operation is stopped and the timer device 35 Eliminates the repetition of ice-making operation and stop for a short period of time, for example every minute, due to ice clogging after the ice-making operation starts, and also avoids a significant decrease in the amount of ice stored in the ice storage (not shown) when ice-making operation is stopped. The temperature sensor 29
senses the temperature rise of the evaporation pipe 5 and the output of the supercooling detection circuit 20 changes from the H signal to the L signal.
The first holding circuit 21 inputs the L signal, but the first holding circuit 21 continuously outputs the H signal.
Further, when the ice making operation is stopped and the operation of the auger motor 10 is stopped, the overload current detection circuit no longer detects the overload current, so it outputs the L signal to the second holding circuit 25, but the second holding circuit 25 continues to output the H signal and the ice making operation is not started.

When the timer device 35 starts operating and a predetermined period of time has elapsed, the timer circuit 35 counts up and outputs an L signal instead of an H signal. This L signal is given to the reset terminals of the first and second holding circuits 21 and 25, both of the first and second holding circuits 21 and 25 output an L signal, and the OR circuit 26 outputs an L signal and 1 transistor 31 is turned off, the third relay coil 30 is de-energized, the third relay switch 30S is turned off, and the drain valve 19 is closed. Also, the first
The NOR circuit 27 outputs an H signal, the second transistor 33 is turned on, and the fourth relay coil 32 is energized, the fourth relay switch 32S is turned on, and the ice-making operation is started. Further, the second NOR circuit 28 outputs an H signal, the timer device 35 is reset, and the oscillation of the oscillation circuit 35A is stopped. Here, when the ice blockage is resolved and no overcurrent flows through the auger motor 10, the overload current detection circuit 22 continues to output the L signal, and the ice making operation continues.

In addition, due to ice clogging, etc., both the supercooling detection circuit 20 and the overload current detection circuit 22 output an H signal, and the drain valve 19 opens and draining starts in the same way as above, and the ice making operation stops and the timer device 35 starts counting and before a predetermined time elapses, when the supercooling detection circuit 20 outputs an L signal due to a rise in the temperature of the evaporation pipe 5, when the predetermined time elapses after the ice making operation is stopped, the 1 transistor 3
1 is turned off and the second transistor 33 is turned on, the drain valve 19 is closed, and the electric compressor 2, blower 3, and auger motor 10 start operating. However, at this time, for example, if ice remains in the cooling cylinder 1 and the auger motor 10 is overloaded and an overcurrent flows, the overload current detection circuit 22 outputs an H signal. The second holding circuit 25 which receives this H signal outputs an H signal. Then, the first transistor 31 is turned on and the second transistor 31 is turned on again.
The transistor 33 is turned off, water drainage is started, the ice making operation is stopped, and the timer device 35 starts counting. Thereafter, ice-making operation is not started for a predetermined period of time, and when the timer device 35 outputs an L signal after a predetermined period of time has elapsed and the auger motor 10 is energized, there is no ice blockage, etc., and no overload current is generated. , the overload current detection circuit 22 continues to be low.
A signal is output and ice making operation continues.

Furthermore, due to the temperature drop in the evaporation pipe 5 due to ice clogging and the generation of overload current in the auger motor 10, both the supercooling detection circuit 20 and the overload current detection circuit 22 output an H signal, and after the ice making operation is stopped, a predetermined signal is output. When the time elapses, the overload on the auger motor 10 is eliminated and the overload current detection circuit 22 continues to output the L signal, but the temperature of the evaporation pipe 5 is low and the supercooling detection circuit 20 continues to output the H signal. While the signal is being output, the drain valve 19 remains open, the electric compressor 2, etc. do not start operation, the ice making operation does not start, and the timer device 35 starts counting again. Then, when the predetermined time has elapsed again, if the ice blockage has been completely eliminated and the supercooling detection circuit 20 is outputting an L signal due to the temperature of the evaporation pipe 5, the ice-making operation is started.

Furthermore, due to the temperature drop in the evaporator pipe 5 due to ice clogging and the overload current of the auger motor 10,
When a predetermined period of time has passed since the ice-making operation was stopped, the ice blockage has not been cleared and the supercooling detection circuit 20
Of course, when both the overload current detection circuit 22 and the overload current detection circuit 22 are outputting H signals, the ice making operation is not started, and when the predetermined time elapses again, the ice blockage has been resolved.
When both the detection circuits 20 and 22 are outputting L signals, ice making operation is started.

Therefore, when ice clogging occurs in the cooling cylinder 1, the supercooling detection circuit 20 or the overload current detection circuit 22 operates and outputs an H signal, and the ice making operation is stopped, the timer device 35 starts operating. However, when the timer device 35 counts up after a predetermined period of time has passed since the ice-making operation stopped, the overcooling detection circuit 20 outputs an L signal due to the temperature rise of the evaporation pipe 5, and the overcooling detection circuit 20 outputs an L signal. When the load is removed and the overload current detection circuit 22 continues to output the L signal, both the first and second holding circuits 21 and 25 output the L signal and the ice making operation is started, and
The temperature sensor 29 detects a temperature rise in the evaporation pipe 5 before the predetermined time elapses, and the supercooling detection circuit 2
0 outputs an L signal, or even if the overload current detection circuit 22 outputs an L signal, the first and second holding circuits 21 and 25 continue to output an H signal and the ice-making operation starts. It will not be done. Therefore, after the ice making operation is stopped due to ice clogging, the ice making operation is forcibly stopped for a predetermined period of time, and the start and stop of the ice making operation are not repeated at short time intervals, and the electric compressor 2 and auger motor It is possible to extend the service life of the vehicle and also to avoid the occurrence of failures.

Further, when the predetermined time has elapsed and the overcooling detection circuit 20 or the overload current detection circuit 22 has detected overcooling or overload, the timer device 3 is activated again.
5 is activated and the ice-making operation is stopped for a predetermined period of time. After that, when the predetermined period of time has elapsed, the ice-making operation is started when the ice blockage is resolved and the supercooling and overload are resolved. The ice-making operation will not be restarted before the ice blockage is cleared, and the ice blockage can be reliably cleared.

In the above embodiment, the temperature sensor 29 was provided on the refrigerant outlet side of the evaporation pipe 5, but the temperature sensor 29
The mounting position is not limited to the above location, and the temperature sensor 29 may be mounted, for example, on the outer peripheral surface of the cooling cylinder 1 to detect temperature changes in the cooling cylinder 1.

(G) Effects of the Invention Since the present invention is a protection device for an ice making machine as shown in the above embodiment, when the cooling cylinder is clogged with ice, the overcooling detection circuit or overload current detection circuit is activated, and the ice making machine is stopped. When the operation is stopped and the timer device starts operating, even if the overcooling of the cooling cylinder or the overload of the auger motor is resolved by the time a predetermined time has elapsed based on the timer device,
The ice making operation continues to be stopped for the predetermined time, and
When the predetermined period of time has elapsed, if either supercooling or overload has not been resolved, the ice-making operation will continue to stop for the predetermined period of time again, so the ice-making operation will start and stop at short time intervals. Electric compressor and auger motor, not to be repeated
Alternatively, the service life of the ice maker mechanism can be extended, and failures can be avoided.

[Brief explanation of the drawing]

1 to 3 show one embodiment of the present invention, in which FIG. 1 is a schematic diagram of a protection circuit, FIG. 2 is a schematic diagram of an operating circuit, and FIG. 3 is a system diagram of an auger ice maker. DESCRIPTION OF SYMBOLS 1...Cooling cylinder, 2...Electric compressor, 3...Auger motor, 6...Auger for ice cutting, 20...Supercooling temperature detection circuit, 21, 25...First and second protection circuits, 22...
Overload current detection circuit, 35... timer device.

Claims (1)

[Claims] 1 Equipped with a cooling cylinder having a passageway for refrigerant fed under pressure from an electric compressor of a refrigeration system on its outer surface, an ice-shaving auger that rotates inside the cooling cylinder, and an auger motor that drives the ice-shaving auger. an overcooling temperature detection circuit that detects ice clogging based on a temperature drop in the cooling cylinder and stops the ice making operation; and an overload current detection circuit that stops the ice making operation based on the overload current of the auger motor. a timer device that starts operation when the ice making operation is stopped due to the operation of the supercooling temperature detection circuit or the overload current detection circuit and outputs an output after a predetermined time; and the supercooling temperature detection circuit or the overload current detection circuit. After the ice making operation is stopped due to the operation of the circuit, the ice making operation is held stopped, and when the timer device outputs an output, and when the supercooling temperature detection circuit and the overload current detection circuit do not detect supercooling or overload. A protection device for an ice maker, comprising: a holding circuit for starting ice making operation.