JPH04148175A - Controller for refrigerator - Google Patents

Abstract

PURPOSE:To reduce the change of the secondary voltage of a transformer and miniaturize the same by the method wherein a circuit, increasing a load to consume only the secondary current of the transformer, is operated when only one piece of driving element is operated to reduce the range of load current. CONSTITUTION:When only one of relays 13a, 23a and photo triode AC switches 26, 27, 28, 29 of the group of driving elements is operated, the coil 23a of a latch relay is put ON to effect recovery and operate and/or stop a compressor 7 and a fan 25. When the change of operating mode, such as the change from operation to stop or from stop to operation, is effected by a switch 22a for a deodorizing device 22, the coil 23a is put ON and the condition of the contact 23b of the latch relay is changed to operate and/or stop the deodorizing device 22. When the operation of a motor damper 8 for a refrigerating chamber 3 is requested, the motor damper 18 of a chilled chamber 19 is put OFF and the motor damper 8 is put ON. When the operation of the same is not requested but the operation of the motor damper 18 for the chilled chamber 19 is requested, the damper 8 is put OFF and the damper 18 is put ON. When the operation is not requested, the dampers 8, 18 are put OFF.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a control device for a refrigerator, and in particular to improvement of secondary side load fluctuations of a transformer.

[Prior Art] Fig. 6 is a side sectional view showing a conventional electronically controlled refrigerator-freezer disclosed in, for example, Japanese Patent Application Laid-Open No. 63-61868. ,(2)
(3) is a refrigerator compartment formed below the freezing compartment (2), and (4) is a freezing compartment (
The cooler installed at the rear of 2), (5) is the freezer compartment (2)
(6) is a temperature detection element such as a thermistor installed outside the refrigerator; (7) is a temperature detection element such as a thermistor installed outside the refrigerator.
is a compressor, (8) is an electric damper that adjusts the amount of cold air flowing into the refrigerator compartment (3), (9) is a heater installed on the side of the main body (1), and (18) is a chilled compartment ( 19) is an electric damper that adjusts the amount of cold air flowing into the refrigerator; (20) is a temperature detection element such as a thermistor provided in the refrigerator compartment (3).

Moreover, FIG. 7 is a diagram showing the electric circuit configuration.

(5) and (6) are the above-mentioned freezer compartment temperature detection element and outside temperature detection element, respectively, (20) is the refrigerator compartment temperature detection element, and (10), (11), (21)
) are resistors connected in series to the freezer temperature detection element (5), the outside temperature detection element (6), and the refrigerator temperature detection element (20), respectively. (12) is a microcomputer (hereinafter abbreviated as microcomputer), which has input ports (12a), (12b), (12g) and output ports (12c), (12d), (12e). , the input boat (12a) is connected to the connection point between the freezer room temperature detection element (5) and the resistor (10), and (12b)
is the connection point between the outside temperature detection element (6) and the resistor (11). (12g) is the refrigerator room temperature detection element (20g)
) and the resistor (21), respectively. Also, each output port (12c), (12d)
.

(12e) is a compressor relay drive circuit (13)
.

It is connected to an electric damper relay drive circuit (14) and a heat retention heater relay drive circuit (15). (13
a) is a compressor relay (14a) connected to the compressor relay drive circuit (13), and an electric damper relay (14a) is an electric damper relay (14) connected to the electric damper relay drive circuit (14).
5a) is a thermal insulation heater relay connected to the thermal insulation heater relay drive circuit (15), and (16) is an AC power source.

Next, the operation of the refrigerator-freezer (1) configured as described above will be explained. Under normal conditions, the freezer compartment temperature detection element (
5) and the output of the refrigerating room temperature detection element (20) are inputted through the input ports (12a) and (12g) of the microcomputer (12) to control the compressor (7) and electric damper (8). Through this control, the temperature is adjusted to maintain the set temperature.

Next, a general operation will be explained based on a flowchart shown in FIG. 8 showing the control operation sequence of this embodiment. The compressor (7), the electric damper (8) and the insulating heater (9) are controlled by the respective outputs from the freezer temperature detection element (5), the outside temperature detection element (6) and the refrigerator temperature detection element (20), respectively. ), in step (100), the maximum number of outputs is limited to 9, for example 2 (that is, the number of simultaneously driven relays is 2), and in step (101) The output is given priority to the compressor (7) and electric damper (8). The above is an electric damper (8
) is for a short period of time, and it was determined that there would be no effect even if the heater (9) was not output during that time.

When it is determined that the output of the electric damper (8) has ended in step (102), the output of the insulating heater (9) is sped up (103), and the number of relays that are simultaneously driven is limited, and the refrigerator-freezer (1 ).

[Problems to be Solved by the Invention] Conventional refrigerator control devices are configured as described above, so as the number of driving elements such as relays and phototriacs increases, it becomes difficult to control the transformer by simply restricting the maximum number that can be driven at the same time. Since it is not possible to reduce the secondary side load current of the transformer, in order to secure the rated voltage on the secondary side of the transformer, the voltage fluctuation rate of the transformer must be lowered. 1
Since it is necessary to raise the rank, the weight of the transformer increases, and if it is mounted on a board, the stress on the board increases, which causes problems such as a slight decrease in reliability and an increase in cost.

This invention was made to solve the above-mentioned problems by reducing the range of change in the secondary current of the transformer, from the minimum load current to the maximum load current, excluding the no-load state. To obtain a control device for a refrigerator, which can reduce the change in the secondary voltage of the transformer within the range of fluctuation of the secondary current even if the voltage fluctuation rate of the transformer is somewhat large, and can downsize the transformer itself. With the goal.

[Means for Solving the Problems] The refrigerator control device according to the present invention is provided with means for increasing the load that simply consumes the secondary current of the transformer when only one drive element operates. It is something that

[Function] When only one driving element operates, the refrigerator control device according to the present invention operates a circuit that increases the load that simply consumes the secondary current of the transformer, thereby increasing the load on the secondary side of the transformer. By increasing the minimum value of the side current, the difference from the maximum load current becomes smaller, and the voltage fluctuation rate can be increased compared to a transformer that controls the same number of drive elements.

The capacity of the transformer can be reduced.

[Example] An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1 and FIG. 2, the same reference numerals as in the prior art indicate the same or equivalent parts, so detailed explanation will be omitted. In the figure, (21) is a control unit composed of the above-mentioned microcomputer (12), etc., (22) is a deodorizing device, and Fig. 2 is a control unit (
21) is a block diagram, (22a) is a switch that the user can set to start or stop (22) of the deodorizing device, (23b) is a relay with a self-holding function (23) (hereinafter referred to as It is a contact point of a latch relay (simply called a latch relay), and stores whether the deodorizing device (22) is to be operated or stopped. (23a) is a latch relay coil, and generally one side of the coil is used to connect the contacts.

The other side is a coil between the contacts.

(12h) is a ROM (read-only memory) in which programs are stored, (12i) is a RAM (random access memory) that stores data and results for arithmetic processing, (26) (27) (28) )
(29) are each phototriacs, and (2
6a) (27a) (28a) (29a) are light emitting parts, and (26b) (27b) (28b) (29b) are light receiving parts. (16) is a commercial power supply, (24) is a power supply circuit including a transformer, and (24a) is a microcomputer (1).
2) power supply, (24b) is the power n of the drive element group, (
25) is a blower. (31) is a drive circuit for the drive element group, and FIG. 3 shows the relationship between the power supply (24b) on the drive element group side of the power supply circuit section (24) and its load power supply, which is determined by a transformer.

Next, regarding the operation, the ROM (12) of the microcontroller (12)
This will be explained with reference to the schematic flowchart of FIG. 4 showing a part of the program stored in h).

First, in step (200), the relays (13a) and (23a) of the drive element group and the phototriac (
26), (27), (28), and (29) is activated. If Yes, proceed to step (201), and in step (201), the latch relay coil ( 23a) to perform recovery, and if NO, turn off the latch relay coil (23a) in step (215), and then proceed to step (202).
Proceed to. Step (202) to step (204)
Then, the compressor (7) and the blower (25) are operated and stopped, and in steps (205) and (206) the deodorizing device (22) is switched from operation to stop and from stop to operation using the switch (22a) that determines whether to stop the deodorizing device (22). When there is a change in the operation mode, as in step (207) to step (209), the coil (23a) of the latch relay is turned on to change the state of the contact (23b) of the latch relay.
The deodorizing device (22) is operated and stopped.

Next, in step (210), the refrigerator compartment (3)
The operation request for the electric damper (8) is determined, and if there is an operation request, the process advances to step (211).

In step (211), the electric damper (18) of the chilled chamber (19) is turned off and the electric damper (8) is turned on. Further, in step (210), the electric damper (
If there is no request for the operation of the chilled chamber (19) in step (212), the process advances to step (213).
) to turn off the electric damper (8), and turn the electric damper (18) off.
) is turned on. Also, if there is no operation request.

In step (214), the electric dampers (8) and (18) are turned off.

In addition, in the above embodiment, the latch relay coil (23a
) section has been described, but as shown in FIG. 5, by providing in advance a circuit that consumes only the secondary current of the transformer, for example, a resistor (30), the flowchart in FIG. The operation of the circuit of this resistor (30) is to perform the glue recovery output of the latch relay (23) in step (201), and the operation of this circuit is to stop the glue recovery output of the latch relay (23) in step (215). It may also be stopped, and the same effect as in the above embodiment can be achieved.

[Effects of the Invention] As described above, according to the present invention, the driving element
Since the structure is configured with a means to increase the load on the secondary side smoothing circuit of the transformer when only one unit operates, the fluctuation range of the secondary side current of the transformer can be reduced, and the voltage It does not require a high fluctuation rate and allows the use of a transformer with a small one-rank capacity, so especially when mounting a transformer on a board, it is possible to reduce stress on the board and reduce costs. There are benefits to be gained.

[Brief explanation of drawings]

FIG. 1 is a side sectional view of a refrigerator according to an embodiment of the present invention, and FIG. 2 is a block diagram showing the circuit of the control section shown in FIG. 1.
Figure 3 is a characteristic diagram showing the relationship between the voltage and electric current of the drive element group.
FIG. 4 is a flowchart showing an operating program according to an actual example of the present invention. Fig. 5 is a block diagram corresponding to Fig. 2 showing another embodiment of the present invention, Fig. 6 is a side sectional view showing a conventional refrigerator-freezer, and Fig. 7 is a block diagram showing the electric circuit of Fig. 6. FIG. 8 is a flowchart showing a conventional operation program. (7) is a compressor, (8) is an electric damper, (9) is a heat insulation layer heater, (12) is a microcomputer, (1
3a is a relay, (18) is an electric damper, (21) is a control unit, (:2) is a deodorizing device, and (23a) is a latch relay coil. (24) is a power supply circuit section, and (24b) is a power supply for the driving element group. (25) is a blower, (26), (27), (28
), (29) is a phototriac, and (31) is a drive circuit. In addition, in FIG. 1, the same reference numerals indicate the same or equivalent parts. of

Claims (1)

[Claims] Multiple driving elements such as a compressor, a blower that forcibly supplies cold air, an electric damper that controls the amount of cold air supplied according to a set temperature, and a heater for keeping warm at low outside temperatures, and a drive that controls these driving elements by a microcomputer. circuit, and connects the drive element and the power supply of the drive circuit to a smoothing circuit connected to the secondary side of the transformer, when only one of the drive elements operates, the transformer A control device for a refrigerator, comprising means for increasing a load on a secondary smoothing circuit.