JPS61125566A - Protective device for auger type ice machine - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a protection device for an auger-type ice-making device equipped with an auger motor that drives an ice-shaving auger that shaves ice formed on the inner surface of a cooling cylinder. .

1) Conventional technology For example, in Japanese Patent Publication No. 56-40259, an auger type ice maker is provided with a hot gas valve that bypasses the condenser and expansion valve between the compressor and evaporator of the refrigerant system, and
A pressure switch is provided on the refrigerant discharge side of the evaporator and connected to the hot gas valve, water supply valve, and drain valve, and when the refrigerant pressure decreases due to overcooling of the cooling cylinder, the pressure switch is turned on and the hot A protection device for an auger-type ice maker is shown that opens a gas valve and a drain valve, and closes the water supply valve.

→ Problems to be Solved by the Invention In the above-described conventional technology, it is difficult to set the operating pressure of the pressure switch. For example, when the operating pressure is set high, K
Since the operation of the drive motor and compressor is stopped even in response to slight pressure fluctuations other than during supercooling, a problem arises in that the ice making operation is stopped unnecessarily. Further, for example, when the operating pressure is set low, the response of the pressure switch that detects the pressure drop is delayed when the drive motor is locked due to overcooling, resulting in a problem that the drive motor and the drive unit may malfunction. comes out.

(Means for Solving Problem 1) In order to solve the above problems, the present invention provides a cooling cylinder around which the evaporation tube of the freezing section is wound and into which water for ice making is supplied, and a cooling cylinder formed on the inner surface of the cooling cylinder. In an auger-type ice making device equipped with an ice-shaving auger that bristles ice-shavings, and an auger motor that drives the ice-shaving auger, a current-voltage conversion device detects the current flowing to the auger motor and changes the output voltage. and a protection circuit that inputs the output voltage and outputs a control signal for controlling operation and stop of the auger motor, and the protection circuit is configured to control the starting current generated when starting the auger motor. The protection circuit is an auger type that continuously outputs an operation signal for the auger motor, and outputs a stop signal for the auger motor when an overload current flows to the auger motor during operation after the start of the auger motor. It is a protection device for ice making equipment.

((E) Effect: With respect to the starting current that occurs when the auger motor starts, the protection circuit does not output a stop signal for the auger motor, the auger motor starts operation, and the auger motor starts operating. When an overload current flows through the auger motor during operation, a protection circuit detects a change in input voltage due to the overload current, outputs a stop signal for the auger motor, and automatically stops the auger motor immediately.

(F) Embodiments Hereinafter, embodiments of the present invention will be described in detail based on FIGS. ta1 to 4.

Figure 3 is an ice making system diagram equipped with an auger type ice making device.
l) is a water storage tank equipped with a water level switch (2). The water storage tank + IIK has a water valve (
3), an overflow pipe (5), and a second water supply pipe (6) are installed. (8) is an auger-type ice-making device that makes ice using ice-making water supplied from the water storage tank (1) through the second water supply pipe (6) into the cooling cylinder (7). In addition, the cooling cylinder (7) continues to the top of the auger type water making device (8),
A refrigerating system evaporation tube (7A) is wound around the outer surface.

(9) is a water storage installed at the top of the auger-type ice making device (8), and a temperature-sensitive or mechanical water storage switch Q (I is equipped with The opening 11 serves as an ice-shaving auger (8A) that shaves ice formed on the inner surface of the cooling cylinder (7) provided inside the auger-type ice-making device (8) and sends it to the water storage (9). This is an auger motor for rotationally driving the ice stirring device (not shown) in the water storage, and (IIA) is a drive device that connects the auger motor Qll and the ice cutting auger (8A) to transmit power. The details of the ice cutting auger (8A) will be omitted. (141 is a cooling cylinder (141) for cooling the water in the water storage tank
7) This is a water supply pipe that sends water inside through the water supply and drainage pipe f151. (161 is a drain pipe that is piped between the water supply pipe a4 and the water supply/drainage pipe 0, and is equipped with a drain valve 0.

Hereinafter, a control circuit for controlling the ice making system shown in FIG. 1 will be explained with reference to FIGS. 1 and 2.

In FIG. 1, the same reference numerals as in FIG. 3 are the same.

■, (211 is the power line, (181 is the power line Q1
Between the power line ■ and the power line 1, there is a series circuit of the water level switch (2) and water pulp relay, a parallel circuit of the auger motor 01) and the compressor 4, and a main A series circuit of the relay switch (278) in the protection device according to the invention and the water storage switch +1 (l) is connected. Note that ■ is a current transformer whose output changes by detecting the current flowing through the auger motor (111). This is a current-voltage converter (hereinafter referred to as a converter) such as the following.

In addition, Fig. 2 shows the schematic circuit of protection device 4, ■, L3]
) is the third one connected to the constant voltage power supply circuit (8). The fourth power supply line, c3z, is a full-wave rectifier circuit connected to the converter,
α9 and attached) are smoothing capacitors and resistors.

(To) is the first amplifier circuit, (To) is the second amplifier circuit in which a positive feedback circuit is formed by the resistor (To), and Gη is the first and second amplifier circuit.
This is a protection circuit equipped with amplifier circuits (g) and (branch)), and the 1++ (plus) input terminals of the first amplifier circuit (to) are connected to the full-wave rectifier circuit C32, and the H( The first reference pressure of the (minus) input terminal is resistance 09, (4t)
K, (4il, f4D, R3, and (
R8) is a capacitor, a resistor, a diode, and a manual resent switch, which respectively constitute a bridge circuit.
(451 is a resistor that determines the second reference voltage of the H-side input terminal of the second amplifier circuit (to), (c), (471 is a resistor that determines the reference voltage of the ... input terminal of the second amplifier circuit) be.

Further, the output terminal of the full-wave rectifier circuit C33 and the input terminals of the second amplifier circuit (to) are connected via a diode (4&) whose forward direction is toward the second amplifier circuit.

Further, the output terminal of the second amplifier circuit (G) is connected to the base of an NPN transistor 151J via a resistor 6G, and the collector of the transistor 611 is connected to a relay coil (27C) on the relay surface. Note that the relay switch (27S) is turned off by the voltage applied to the relay coil (27C).

The operation of the control circuit will be explained below.

When the operation switch Nishiki is turned on at the start of operation of the ice making device (8), power is supplied via the power lines ) is on, the water pulp relay G is energized, the water pulp (3) is opened, and water is supplied to the water storage tank f11. Also, the water storage switch 0 is turned on.
When α and the relay switch (273) are both turned on, a large starting current flows to the auger motor 011 at the same time as the operation switch (I&) is turned on.

Then, this starting current is detected by the converter and is full-wave rectified to become a high-level signal, which is input to the input terminals of the first and second amplifier circuits. . At this time, the first input terminal of the l-1 side input terminal of the first amplifier circuit (G)
Since the reference voltage is set to a value lower than the voltage generated by the converter Ci! by the normal operating current of the auger motor (111), the first amplifier circuit is connected to the auger motor aυ. The power supply voltage is output almost at the same time as starting, and its value is the same as that of capacitor +411 and resistor M3.
(441, (second
(-1 (applied to the II input terminal) of the amplifier circuit (to).

As shown in FIG. 4, the voltage at the H-side input terminal of the second amplifier circuit (G) changes over time from the power supply voltage (En) to the capacitor (411 and resistor (42, 04),
Attenuates at a constant rate determined by the value of 451, and resistor 04
1, (attenuates to a value determined by the division ratio of 4, that is, the second reference voltage (D). Here, this second reference voltage (D
is the threshold value used to determine whether the current flowing through the auger motor (older auger motor) is normal or abnormal. In addition, the input voltage at the H-side input terminal of the second amplifier circuit (to) is attenuated, and the voltage value (E
+) so that the time (to) to reach the auger motor (old) is longer than the time (t,) required for starting the auger motor (old).
The values of capacitor 0D and resistor (4z, (Foundation)), (451) are set.As a result, when starting the auger motor, the voltage at the f-1 side input terminal of the second amplifier circuit ■ becomes (-
higher than the potential of the H9111 input terminal, second amplifier circuit G)
outputs a low level signal which is an operating signal, the transistor 5D is off, the relay coil (52C) is not energized, the relay switch (52S) continues to be on, and the auger motor (111 and Electricity continues to be supplied to the compressor Iso, and ice making operation begins.
From now on, the auger motor 011 is de-energized, and the potential of the H-side input terminal of the second amplifier circuit (to) is changed to the first amplifier circuit (to).
The second reference voltage (EIIC) is maintained until the input voltage of the (1) input terminal becomes a low level signal.

Also, since the output voltage of the converter (to) due to the operating current after starting the auger motor (Ill) is lower than the second reference voltage (■), the input voltage of the H side input terminal of the second amplifier circuit (sub) is (T). The second amplifier circuit (2) continues to output an L level signal, and the relay switch (27S) continues to be in the on state.

Thereafter, when a predetermined amount of ice is stored in the water storage (9), the water storage switch Ool is turned off, the auger motor 01) and the compressor θ are de-energized, and the ice-making operation is stopped. When the amount of water stored decreases, the water storage switch uo
l is turned on, the auger motor rotor υ and the compressor (c) are energized, and the protection device @ is operated in the same manner as at the start of the ice-making operation, and the ice-making operation is restarted. The amount of water in the ice storage hawk (9) is kept approximately constant due to the ice making operation based on the on/off status of the water storage switch (1).

When ice-making operation is performed as described above, for example, ice becomes clogged between the ice-shaving auger (8A) and the cooling cylinder (7), and the ice-shaving auger (8A) is locked even momentarily. Sometimes, when the ice cutting auger (8A) is locked, the auger motor (11) is also locked, and this auger motor is forced to stop operating, and the auger motor (old) K is locked at a lock current higher than the operating current when energized. flows, converter track and full wave rectifier circuit c3? A 1-level signal (with a voltage corresponding to the above-mentioned lock current) is applied to the (-H) input terminals of the first and second amplifier circuits (G) and (to) through J (7). The circuit (to) continues to output the NO level signal, but no current flows to the input terminal of the second amplifier circuit cN, and the input terminal of the second amplifier circuit cN outputs the second reference voltage. is being entered. Therefore, (-
)-1(til+Ill inputs the high level signal from the full-wave rectifier circuit ■, the second amplifier circuit (to) outputs a no level signal which is an operation stop signal, and the transistor 511 is turned on to close the relay coil. (27C) is energized, the relay switch (27S) is turned off, and the auger motor (Ill and compressor ① are both de-energized and stops operating. Also, the second amplifier circuit) and the repel signal are resistors (to). (-H) is fed back to the input terminal, a positive feedback circuit is formed, and even if the ice cutting auger (8A) is no longer locked, the second amplifier circuit continues to output the no-repel signal. The auger motor 01) and the compressor (2) continue to stop operating.

After that, the user of the ice making device (8) must switch the reset switch (
When R3) is pressed and the input terminal of the second amplifier circuit (G) inputs a higher level signal than the + side input terminal from the third power supply line via this reset switch,
The second amplifier circuit (to) outputs a low level signal, and the transistor 6υ is turned off. Then, the second relay coil (27C) is de-energized by turning off the transistor 5D.
The relay switch (273) is turned on and the ice making device is turned on again.
Ice-making operation is started in which power supply to the auger motor (old) and compressor motor (4) is controlled by turning on and off the water storage switch GO.

Note that when the reset switch (R3) is turned on and the second amplifier circuit (G) outputs a low level signal, the second amplifier circuit (G) outputs a low level signal.
The input to the + side input terminal of the amplifier circuit also decreases due to positive feedback, and its value decreases from the second
Resistors 2, 146), (47) so that the voltage is below the reference voltage.
Since the value of 1 is set, reset switch (R3)
Even if it is turned off, the second amplifier circuit (to) continues to output a low level signal.

Therefore, even if a large starting current occurs in the auger motor at the start of ice-making operation, the output of the first amplifier circuit of the protection circuit C371 immediately becomes a level signal, and the second amplifier circuit rule) G-] The 0Ill input terminal is connected to the auger motor (
11) at the time of starting...(Since the voltage rises to a higher voltage than the input voltage of the 111 input terminal, the second amplifier circuit 06) continues to output a low level signal and the relay switch (27)
S) continues to be on, and the operation of the auger motor (old) and compressor G is reliably started, and the ice-making operation can be promptly started. Also, during ice-making operation, if the auger motor 01) is locked even momentarily and the current flowing through this auger motor increases and the output voltage of the converter increases, the output voltage from the H input terminals of the second amplifier circuit ( +
The input voltage of the side input terminal becomes high, and the second amplifier circuit (to)
can output a low level signal and stop the auger motor 011 and compressor
It is possible to avoid overload operation of the ll, and prevent repeated operation and stop due to locking of the auger motor (111). damage to the auger motor aυ and drive device (
IIA) It is possible to reliably protect the ice during the ice-making operation. Even if a large starting current is generated in the motor, there is no malfunction that causes the auger motor to stop, and the auger motor can be started reliably. As a result, ice-making operation can be started smoothly. If an overload current flows to the auger motor due to locking of the ice cutting auger after the motor has started, the operation of the auger motor can be stopped immediately by the output of the protection circuit, so that the auger motor can be stopped at short intervals. This prevents repeated operation and stop, which avoids damage to the auger motor and the drive device that transmits the power of the auger motor, protects the auger motor and the drive device, and allows the ice making device to operate normally for a long period of time. You can do it.

[Brief explanation of the drawing]

Figures m1 to 4 show an embodiment of the present invention, in which Figure 1 is a schematic control circuit diagram of an ice making device, Figure 2 is a schematic circuit diagram of a protection device, and Figure 3 is an ice making device equipped with an auger type ice making device. Ice making system diagram, Figure 4 shows the second amplifier circuit when starting the auger motor)
FIG. 3 is an input terminal voltage characteristic diagram. (7)...Cooling cylinder, (7A)...Evaporation tube, (
8)...Auger type ice making device, (8A)...Auger for ice cutting, (9)...Water storage, (11)...
Auger motor, ■...Protective device, ■...Current voltage converter, c3η...Protection circuit. Applicant Sanyo Electric Co., Ltd. and one other representative Patent attorney Shizuo Sano Figure 1 Figure 3r21 Figure 4

Claims (1)

[Claims] 1. A cooling cylinder around which the evaporation tube of the refrigeration system is wound and into which ice-making water is supplied, an ice-shaving auger that scrapes the ice formed on the inner surface of the cooling cylinder, and a drive for the ice-shaving auger. an auger-type ice making device comprising an auger motor that controls the auger motor, a current-voltage converter that generates an output voltage according to a change in the current of the auger motor, and a control signal that controls operation and stop of the auger motor based on the output voltage. The protection circuit continuously outputs an operation signal for the auger motor in response to a starting current generated when the auger motor is started, and the protection circuit outputs an operation signal for the auger motor after starting the auger motor. A protection device for auger-type ice making equipment that outputs a stop signal for the auger motor based on overload current that occurs.