JPH07104089B2 - Control device for electric refrigerator-freezer - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for an electric refrigerator / freezer / refrigerator, particularly when the power source is automatically restored after a power failure, for example, it is operated in the operating state before the power failure before the non-energized period has passed a predetermined time. The present invention relates to a control device for an electric refrigerating / freezing / refrigerating cabinet, which is initialized after the non-energized period has passed a predetermined time without being restored to a state in which it was operated before a power failure.

[0002]

2. Description of the Related Art Electric freezers, refrigerators and freezers are equipped with a latch circuit so that even if the power is temporarily cut off due to movement or power failure, the operation continues in the same state as before restoration from the power failure. There is. FIG. 10 shows a conventional electric freezer-refrigerator / refrigerator control device of this type. When one of the freezing, refrigerating, warming, and defrosting switches 1 to 4 is turned on, that is, pressed, the corresponding control is performed. The output Q of the provided flip-flop (FF) circuits 6 to 9 is latched at the switch state as L level. These FF
The circuits 6 to 9 are built in the latch IC 5, and a positive voltage is applied to the anode terminal V _CC of the latch IC 5 from the DC power source 10 via the diode D1, and this positive voltage constantly charges the capacitor C4. There is.

Therefore, even if the AC power supply 11 is turned off due to movement or a power failure (both of which are referred to as a power failure), the charge stored in the capacitor C4 holds the latched contents of the FF circuits 6 to 9 for a predetermined period. When the power supply of the AC power supply 11 is restored, the operation is restarted in the same state as before.

It should be noted that LD1 to LD4 are light emitting diodes, which are turned on in response to turning on of the switches 1 to 4, respectively. Now, for example, when the switch 2 for refrigeration is turned on, F
The F circuit 7 sets its output Q to the L level and holds that state. At this time, the light emitting diode LD2 is turned on, the transistor TR5 is turned on, the relay RL3 is energized, and the reference voltage of the comparator 15 changes according to the change in the inside temperature detected by the thermistor 17 under the reference voltage V _F for refrigeration. The level of the output of the comparator 15 changes. During the refrigerating operation, the output of the comparator 15 is at the L level, so the transistor TR4 is turned on. Therefore, the contact of the relay RL1 is connected to the compressor device 12 side, and the comparator 1
Cooling of the inside of the refrigerator proceeds until the output of 5 changes to the H level.

When the freezing switch 1 is turned on, FF times
The path 6 keeps its state by setting its output Q to L level,
The light emitting diode LD1 is turned on. At this time, the FF circuit
7 is released and its output Q becomes H level.
Then, the transistor TR5 is turned off and the relay RL3 is deenergized.
The reference voltage of the comparator 15 is the reference voltage V for freezing.
_RThe output of the comparator 15 becomes H level under
Until the compressor device 12 operates and the refrigeration operation is performed.
It

When the defrosting switch 4 is turned on, the L level is held at the output Q of the FF circuit 9 and the light emitting diode LD4 is turned on. And the output Q of this FF circuit 9
Based on the L level, the comparator 15 is forced to output the H level at which the transistor TR4 is turned off.
As a result, the relay RL1 is deenergized and the compressor device 1
After the AC power supply 11 to 2 is cut off, the temperature of the inside of the refrigerator naturally rises and defrosting is performed.

On the other hand, when the heat storage switch 3 is turned on,
The FF circuit 8 sets its output Q to the L level and holds that state, and turns on the light emitting diode LD3. At this time, as in the case of defrosting, the output of the comparator 15 is forcibly set to the H level, the transistor TR2 is turned on to energize the relay RL2, and the heater 13 is supplied with the AC power supply 11
Configure the circuit that supplies the voltage of and start the heating operation.

[0008]

However, the conventional control device for the electric refrigerator-freezer-refrigerator has the following drawbacks. That is, if the non-energized state continues for a long time due to a power failure, the voltage of the status holding capacitor C4 drops to such an extent that the latch contents of the FF circuits 6 to 9 cannot be held, and when the power failure is restored, there is no relation to the previous status. It becomes a state and performs an undesired operation. FF circuits 6 to 9 especially due to noise
When all outputs Q of H become H level, it becomes a refrigerating operation state.

When a phase split starter motor is used for the compressor device 12, a posistor or the like is connected in series to its start winding to protect it from burnout, and the temperature of the posistor drops when restarting. You have to use an electric clock timer to wait until the resistance drops,
It was expensive and structurally large.

In defrosting, the operation of the compressor device 12 is stopped and defrosting is performed by a natural temperature rise. Therefore, the temperature inside the refrigerator does not rise because the heat insulating effect inside the refrigerator is good, and it takes time. If it is taken and forcibly scraped off, there is a possibility that the cooler may malfunction.

An object of the present invention is to solve the above-mentioned drawbacks. When the power failure is restored and the non-energized period is within the predetermined time, the operation is performed in the previous operating state, and when the non-energized period is the predetermined time or more. (EN) Provided is a control device for electric freezing, refrigerating, and refrigerating, which is initialized regardless of the state in which it was previously operated, and cannot be operated in any state so as not to be operated in an undesired state. Is intended.

[0012]

In order to achieve the above object, a control device for an electric freezer-refrigerator / refrigerator according to the present invention holds a switch for selecting freezing, refrigerating, refrigerating, and defrosting and its state. Switch means each having a latch circuit, a compressor device for cooling the inside of the refrigerator, a heater for warming the inside of the refrigerator, a controller for driving the compressor device or the heater according to the conditions selected by the switch means, and when energized Monitors the discharge voltage of the state-holding capacitor that is constantly charged and the state-holding capacitor when the power is restored after a power failure, and when the discharge voltage is below a predetermined voltage, the above-mentioned freezing, refrigerating, and warming And a discharge voltage monitoring circuit for initializing each defrosting latch circuit.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows the configuration of an embodiment of an input portion of a control device for an electric refrigerator-freezer / refrigerator according to the present invention, and FIGS. 7 and 8 together form one drawing. 1 is extracted from the configuration of an embodiment of a control device for an electric refrigerator-freezer refrigerator according to the present invention. As for the arrangement relationship between FIG. 7 and FIG. 8, the right side of FIG. 7 is connected to the left side of FIG. 8, and the connecting lines are connected in the same order.

In FIGS. 1 and 7 and 8, the same components as those in FIG. 10 are designated by the same reference numerals, and 18 is a discharge voltage monitoring circuit. The discharge voltage monitoring circuit 18 is a comparator 19 that monitors the voltage of the state-holding capacitor C4.
And a transistor TR3 which is turned on / off according to the output level of the comparator 19.

When the power failure described above occurs, the voltage charged in the state-holding capacitor C4 gradually spontaneously discharges with the lapse of time, and the charging voltage drops. When the power failure is restored, the comparator 19 compares the voltage divided by the resistors R41 and R43 with the voltage of the state holding capacitor C4. When the voltage of the state holding capacitor C4 is higher, the output of the comparator 19 is at H level, the transistor TR3 is turned off, and the discharge voltage monitoring circuit 1
No cancel signal is transmitted from 8 to each S terminal of the FF circuits 6 to 9 in the latch IC 5.

That is, the state-holding capacitor C4 has a voltage sufficient to hold the contents of each latch of the FF circuits 6 to 9 in the latch IC 5, and indicates that the latch IC 5 is being continuously driven. And H of comparator 19
By the level output, the state-holding capacitor C4 is recharged through the resistor R40 and the diode D38 to prepare for the next power failure.

When the voltage of the state holding capacitor C4 is lower than the voltage divided by the resistors R41 and R43, it is judged that the latch contents of the FF circuits 6 to 9 in the latch IC 5 cannot be held. , The comparator 19 outputs an L level. When the output of the comparator 19 is at L level, the positive voltage of the DC power supply 10 is applied to the latch IC 5 through the diode D1, but the diode D38 and D39 does not recharge the state holding capacitor C4 and the previous voltage is maintained. Is retained.

Further, since the output of the comparator 19 is at L level, the transistor TR3 is turned on, the cancel signal is transmitted from the discharge voltage monitoring circuit 18 to the S terminals of the FF circuits 6 to 9 in the latch IC 5, and the FF circuit 6 is transmitted.
All outputs Q to 9 are initialized to H level. Even if all the outputs Q of the FF circuits 6 to 9 are initialized to the H level, the freezing / refrigerating and refrigerating storage is not operated in any state, which will be described later with reference to FIG.

Refrigeration switch 1 under initialized condition
When any one of the heat storage switch 3 is turned on, for example, when the refrigeration switch 2 is pressed, the R signal is input to the corresponding FF circuit 7 and the refrigeration signal is stored and held. At this time, the S signal is input to the other FF circuits 6, 8 and 9 so that the exclusive state is selected.
Then, for the discharge voltage monitoring circuit 18, the comparator 1
The non-inverting input terminal of 9 is forcibly set to the H level, and the output of the comparator 19 is inverted from the L level to the H level. As a result, the state-holding capacitor C4 is recharged via the resistor R40 and the diode D38, and the state becomes ready for the next power failure.

The freezing switch 1 to the heating switch 3 are provided with differentiating circuits R1, C1 and R2 composed of resistors and capacitors.
And C2 and R3 and C3 are added respectively. Therefore, if the width of the differential waveform created in the differentiating circuit is narrowed, it is possible to prevent problems caused by simultaneous pressing of the freezing switch 1 or the heating switch 3.

That is, the shaded area in FIG. 9 indicates the period during which the switch is being pressed. For example, when the refrigerating switch 2 is pressed while the freezing switch 1 is being pressed, the differential circuit Since the differential waveform width is narrow, the signal of the cold storage switch 2 which is pushed almost simultaneously is stored in the FF circuit 7. At this time, that is, which switch signal is stored, the R signal and the S signal are input so that the exclusive selection is performed as described above, and the corresponding light emitting diode LD1. Alternatively, it is identified by lighting of LD2. Although the simultaneous pressing of the freezing switch 1 and the refrigerating switch 2 has been described, the same thing can be applied to the warming switch 3, and the freezing switch 1, the refrigerating switch 2, and the warming switch 3 can be connected to each other. It is possible to prevent problems due to simultaneous pressing.

FIG. 2 shows an embodiment of the freezing / refrigerating selection circuit of the control device for the electric freezing / refrigerating / freezing room according to the present invention. FIG. 7 and FIG. 8 are combined to form one drawing. The present invention is extracted from the configuration of an embodiment of a control device for an electric freezer-refrigerator and a refrigerator according to the present invention.

The comparator 16 is connected in parallel with the comparator 15, and the comparator 16 is electrically disabled during the refrigerating operation, and the comparator 1 during the refrigerating operation.
Both 5 and 16 are configured to operate as electrically effective. That is, in the refrigerating operation, the non-inverting input terminal of the comparator 16 is forcibly dropped to the L level so that the comparator 16 is electrically disabled.
The H level is output from the comparator 16. In the case of FIG. 2, the comparator 16 is shown to be disabled by turning on the transistor 20, but in FIGS. 7 and 8, the comparator 16 is disabled with the L level of the output Q of the FF circuit 7. Is configured.

Therefore, during the refrigerating operation, as in the conventional case, the comparator 15 changes according to the change in the refrigerating reference voltage divided by the resistors R23 and R24 and the temperature inside the refrigerator detected by the thermistor 17. The voltage input to the non-inverting input terminal of is compared, but during the refrigerating operation, both the comparators 15 and 16 operate as valid and depend on the operation of the comparator 16. That is, the reference voltage for refrigeration divided by the resistors R19 and R20 and the voltage input to the non-inverting input terminal of the comparator 16 that changes according to the change in the internal temperature detected by the thermistor 17 are input to the comparator 16. The transistor TR4 is turned on and power is supplied to the compressor device 12 until it is compared and the comparator 16 outputs the L level. At this time, the comparator 15 outputs H level.

Reference numeral 21 is a resistor, which is connected in parallel to the series circuit of the resistor R22 and the thermistor 17 in accordance with the set temperature in the refrigerator, and each of the comparators 15 and 16 is not connected in accordance with the set temperature. The voltage input to the inverting input terminal is changed to correspond to the set temperature. Therefore, the resistor 21 is provided for the set temperature.

FIG. 3 is a block diagram showing an embodiment of a protection circuit of a control device for an electric freezer / refrigerator according to the present invention when a phase splitting start motor is used in a compressor device. It is extracted from the configuration of one embodiment of the control device for the electric refrigerator-freezer-refrigerator according to the present invention, which together constitute one drawing.

The compressor device 12 is the phase splitting start motor 2
2, the posistor 23 is connected in series to the start winding of the phase-splitting starter motor 22 to protect the start winding from burning. Then, the comparator 15, the capacitor C5, the diode D35 and the resistor R
The motor protection circuit 24 is composed of 30 to R35, and the output of the motor protection circuit 24 is the diodes D27 and D3.
Control the comparators 16 and 15 respectively via 0,
The phase split start motor 22 is protected.

Since the relay RL1 is energized during the operation of the compressor device 12, the capacitor C5 is charged through the resistor R33 and the diode D35.
Under this condition, the voltage V _{A at the} connection point A determined by the resistors R31, R32, and R30 is set to be higher than the voltage V _{B at the} connection point B divided by the resistors R33 and R34. 15 outputs the H level.
Therefore, the diodes D27 and D30 are both reverse-biased, and the temperature inside the refrigerator is normally detected by the thermistor 17 without affecting the comparators 15 and 16.

When the temperature inside the chamber falls below the set temperature,
When the star TR4 is turned off, the relay RL1 is de-energized.
The suppressor device 12 is stopped. At this time, the voltage at the connection point A
Pressure V _AIs mainly the series combination resistance of resistors R31, R33, and R34.
It is a value determined by the partial pressure between the resistance and the resistance R30.
Pressure V_ddIt is much lower than. On the other hand, the transistor TR4
The voltage charged in the capacitor C5 immediately after turning off the
Time constant determined by the capacitor C5 and the resistor R35
Discharge is started based on the
V immediately after stopping_B> V_AAnd the comparator 15 has an L level
Is output.

By this L level, the comparators 15 and 1
The respective outputs of 6 are forcibly controlled to the H level via the diodes D30 and D27. This state is maintained until the discharge voltage of the capacitor C5 decreases and V _B <V _A, and the operations of the comparators 15 and 16 are invalidated regardless of the temperature detection by the thermistor 17. That is, until the discharge voltage of the capacitor C5 drops to a predetermined voltage, no matter how the inside temperature changes, the temperature is no longer detected and the compressor device 12 cannot operate. Therefore, during this period, the temperature of the posistor 23 decreases, the resistance value thereof decreases, and the phase-split start motor 22 can be restarted.

FIG. 4 shows a configuration of an embodiment for monitoring the latch circuit, and FIG. 7 and FIG. 8 are combined to form one drawing. It is extracted from the configuration of one embodiment.

Reference numeral 25 is a latch monitoring circuit, which includes a transistor 26, diodes D44 to D48, resistors 46 and 4,
7, the latch monitoring circuit 25 is configured. Now, for example, when the outputs Q of the FF circuits 6 to 8 are all at the H level due to noise or the like, the transistor 26 is turned off and the comparators 16 and 15 are connected via the diodes D47 and D48.
Is forcibly controlled to the H level.

As a result, the transistor TR4 cannot be turned on, and the conventional refrigerating operation state described with reference to FIG. 9 is avoided. Further, as described with reference to FIG. 1, the cancel signal is transmitted from the discharge voltage monitoring circuit 18 to the FF circuits 6 to 9 after the power failure continues for a long time, and each output Q of the FF circuits 6 to 8 becomes the H level. Does not enter the freezing operation state, and none of the states becomes the initial state. The transistor 26 is preferably of PNP type so that the current corresponding to the base current I _B does not flow out from the FF circuits 6 to 8, and the resistor R is used.
A small value is used for 47.

FIG. 5 shows the configuration of another embodiment for monitoring the latch circuit. In the figure, the latch monitoring circuit 25 includes diodes 44 to 46, 49 and a pull-up resistor R48.
It consists of and.

When the outputs Q of the FF circuits 6 to 8 are all at the H level, a positive voltage is applied from the resistor R48 side to the thermistor 17, and the comparators 15 and 16 are provided.
The input voltage to the non-inverting input terminal rises, and the outputs of the comparators 15 and 16 are forced to H level as in the case of FIG.
Controlled by level. If any of the outputs Q of the FF circuits 6 to 8 is at L level, the diode D49 is reverse biased and has no effect on the comparators 15 and 16.

FIG. 6 shows an embodiment of a defrosting circuit for defrosting using a heater, and FIG. 7 and FIG. 8 are combined to form one drawing. It is extracted from the configuration of one embodiment of the control device for the hot storage.

The defrosting circuit for defrosting by using this heater is a diode D at the L level of the output Q of the FF circuit 9.
The transistor TR2 is controlled via 42, and
The operation of the comparators 15 and 16 is changed through the diode D32, the resistor R29, and the diode D29, in particular, the reference voltage of the comparator 15 is changed to raise the set temperature at which the transistor TR4 is turned on and the transistor TR2
A series circuit of a resistor R45 and a diode D43 is connected to the output Q of the FF circuit 9 from the collector side of the resistor R4 and
4 through the diode D23 from the connection point between R4 and R45
It is connected to the S terminal of the F circuit 9 and is configured to hold the output Q of the L level when the output Q of the FF circuit 9 becomes the L level by the defrosting switch 4.

When the defrosting switch 4 is pushed during the refrigerating operation, the output Q of the FF circuit 9 becomes L level, the resistor R29 is inserted in parallel with the resistor R24, and the reference voltage of the comparator 15 is reached. Is decreased, and the setting of the in-compartment temperature at which the output Q of the comparator 15 becomes L level is correspondingly increased. At the same time, the transistor TR2 is turned on via the diode D42, the relay RL2 is energized, and a circuit for supplying a voltage from the AC power supply 11 to the heater 13 is established.

At this time, the resistors R45 and R12 are connected in parallel, and the combined resistance of the resistors R45 and R12 is set to be smaller than that of the resistor R44.
Even if the collector voltage of the transistor TR2 rises, the L level is substantially input to the S terminal of the FF circuit 9, and the output Q of the FF circuit 9 is still held at the L level, and the heater 13 is defrosted. Continues to be energized. When the inside of the refrigerator reaches the defrosting set temperature such as 9 ° C., the output of the comparator 15 is inverted to the L level, the transistor TR4 is turned on, the relay RL1 is energized, and the compressor device 12 is driven. With diode D2
The S signal is applied to the FF circuit 9 via 3. Therefore, its output Q becomes H level and the diodes D29 and D32
Is reverse-biased and the reference voltage of the comparator 15 becomes a voltage divided by the original resistors R23 and R24, and the refrigerating operation is automatically started.

[0040]

As described above, according to the present invention, in the case of claims 1 and 2, when the power is automatically restored after a long power failure, no initial state is selected,
It is possible to realize an electric freezer-refrigerator / freezer that avoids undesired operations.

According to the third aspect, even if a malfunction occurs due to simultaneous pressing, effective selection can be immediately made. In the case of claim 4, since the heater is used for defrosting, the time for defrosting is shortened, and the occurrence of failure of the cooler due to manual scraping is avoided.

In the fifth aspect, the phase-splitting motor can be prevented from being burned, the circuit can be downsized, and the number of parts can be reduced, so that the cost can be reduced. In the case of claim 6, since freezing or refrigerating is selected by electronic control, accurate temperature setting is possible.

[Brief description of drawings]

FIG. 1 is an example configuration of an input portion of a control device for an electric refrigerator-freezer refrigerator according to the present invention.

FIG. 2 is a configuration of an embodiment of a freezing / refrigerating selection circuit of a control device for an electric freezing / refrigerating / freezing room according to the present invention.

FIG. 3 is an example configuration of a protection circuit when a phase splitting starter motor is used in a compressor device in a control device for an electric refrigerator-freezer refrigerator according to the present invention.

FIG. 4 is a configuration of an embodiment for monitoring a latch circuit.

FIG. 5 is another example configuration for monitoring a latch circuit.

FIG. 6 is an example configuration of a defrosting circuit that defrosts using a heater.

FIG. 7 is a part of the configuration of an embodiment of a control device for an electric freezer-refrigerator according to the present invention.

FIG. 8 is a portion of an embodiment configured together with FIG.

FIG. 9 is an explanatory diagram of waveform operation by simultaneously pressing input switches.

FIG. 10 is a circuit diagram of a conventional controller for a freezer-refrigerator / refrigerator.

[Explanation of symbols]

 1, 2, 3, 4 Switch 5 Latch IC 6, 7, 8, 9 FF circuit 12 Compressor device 13 Heater 17 Thermistor 18 Discharge voltage monitoring circuit 22 Phase splitting starter motor 24 Motor protection circuit 25 Latch monitoring circuit C4 State holding capacitor

Claims (6)

[Claims] 1. A switch means each having a switch for selecting freezing, refrigerating, warming and defrosting and a latch circuit for holding the state, a compressor device for cooling the inside of the refrigerator, and a heater for warming the inside of the refrigerator. The control unit that drives the compressor device or the heater according to the conditions selected by the above switch means, the state-holding capacitor that is constantly charged when energized, and the discharge voltage of the state-holding capacitor when power is restored after a power failure are displayed. A control device for an electric refrigerator-freezer refrigerator provided with a discharge voltage monitoring circuit which monitors and discharges the latch circuits for freezing, refrigerating, warming and defrosting when the discharge voltage is below a predetermined voltage. . 2. A switch means each having a switch for selecting freezing, refrigerating, warming and defrosting and a latch circuit for holding the state, a compressor device for cooling the inside of the refrigerator, a heater for warming the inside of the refrigerator, The control unit that drives the compressor device or the heater according to the conditions selected by the above switch means, the state-holding capacitor that is constantly charged when energized, and the discharge voltage of the state-holding capacitor when power is restored after a power failure are displayed. A discharge voltage monitoring circuit that monitors and initializes the freezing, refrigerating, heating and defrosting latch circuits when the discharge voltage is below a predetermined voltage, and the freezing, refrigerating and heating storage latch circuits And a latch monitoring circuit for monitoring the signal holding state of the above, and invalidating the operation of the compressor device when these three latch circuits are initialized. A control device for the equipped electric refrigerator-freezer refrigerator. 3. The electric freezer-refrigerator / refrigerator control apparatus according to claim 2, wherein each of the freezing, refrigerating and heating switches is configured to transmit a signal to each latch circuit via a differentiating circuit. 4. The electric freezer-refrigerator / refrigerator controller according to claim 2, wherein the controller is configured to drive a heater when a defrosting switch is selected. 5. The refrigeration system according to claim 2, wherein a phase split start motor is used in the compressor device,
A control device for an electric refrigerating / freezing / refrigerating machine, wherein a motor protection circuit for supplying power to the phase-splitting starter motor after a predetermined time has elapsed when the refrigerating switch is selected is provided in the control section. 6. The control unit according to claim 2, wherein the control unit uses a thermistor as a shared temperature detector for freezing and refrigerating, and a refrigerating control circuit and a refrigerating control circuit for controlling driving of the compressor device are provided with OR. An electric refrigerating / refrigerating / refrigerating control device comprising a refrigerating / refrigerating selection circuit which is configured in a circuit and whose refrigerating control circuit side is invalidly controlled when a refrigerating switch is selected.