JPS5963475A - Storehouse - 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 (a) Field of the Invention The present invention relates to storage facilities such as refrigerators, freezers, showcases, etc., which are equipped with a refrigeration device for cooling the inside of a predetermined compartment to a temperature below the freezing point or slightly above the freezing point. 1- Concerning energy saving and stabilization of control operations.

(b) Background Art and Problems The refrigerator-freezer shown in FIG. 1 will be explained with reference to FIGS. 2 and 3. (1) is a refrigerator-freezer main body, with an insulating partition wall (2) dividing the inside of the main body (1) into a freezer compartment (3) and a refrigerator compartment (4), and an evaporator ( 8), and the air cooled by the evaporator (8) is circulated between the freezer compartment (3) and the refrigerator compartment (4) by an electric blower 01). Second
The figure shows the refrigerant circulation circuit of the refrigeration system, in which the refrigerant consists of an electric compressor (5), a condenser (6), a solenoid valve (9), a capillary cheep (7) as a pressure reducing device, an evaporator (8), Check valve θ
0) and returns to the electric compressor (5). Fig. 3 shows a control circuit, in which (12) is a temperature control device that directly or indirectly senses the temperature of the commercial AC power supply and (13) the temperature of the freezer compartment (3) to open and close the contacts.
The temperature sensing part is provided in the freezing compartment (3), in the cold air blowing part to the freezing compartment (3), or in the evaporator (8), and is substantially in the freezing compartment (3).
It is sufficient if temperature control can be achieved.

In this configuration, when the freezer compartment (3) is not cooled to a predetermined lower limit temperature, the temperature control device (+3+ closes the contacts and the electric compressor (5), solenoid valve (9) and electric blower ([1 ) is energized, the solenoid valve (9) opens the refrigerant passage, and the electric compressor (5) and electric blower (11) are started to cool each room (31 (4+). In this case, the refrigerator compartment (4
) is maintained within a predetermined temperature range by a damper mostat (a) that opens and closes the cold air outlet to the refrigerator compartment (4) according to the temperature of the refrigerator compartment (4). When the freezer compartment (3) is cooled to the lower limit set temperature of the temperature control device 03), the temperature control device 03) is opened and the electric compressor (5) and electric blower θj) are opened.
Stop operation and de-energize the solenoid valve (9) to close the refrigerant passage.

Then, when the temperature of the freezer compartment (3) rises again and reaches the upper limit set temperature of the temperature control device 03), the temperature control rack f (13) is closed and the electric compressor (5) and the electric blower 01) are energized and operated. At the same time, the solenoid valve (9) is energized to open the refrigerant passage. In this way, the temperature control device (13) simultaneously controls the energization and de-energization of the solenoid valve (9), the electric compressor (5), and the electric blower 0), and the chamber (3H4,) is controlled to maintain a predetermined temperature range. will be maintained.

The reason for providing the solenoid valve in this configuration is the electric compressor (5
) is stopped, close the solenoid valve (9) to separate the pressure between the high pressure side and the low pressure side of the refrigerant circuit to prevent refrigerant gas from flowing into the evaporator (8) on the low pressure side from the high pressure side. Make sure that the temperature of the container does not rise too much (3) (, vi
This prevents the temperature rise from becoming too large. That is, if this temperature rise is large, the stop time of the electric compressor (5) will be short, resulting in poor operating efficiency and high power consumption. If the compressor of the electric compressor is a reciprocating type, the check valve θ0) is unnecessary because the discharge side (high pressure side) and suction side (low pressure side) of the compressor are separated by a valve inside the compressor. However, in the case of a rotary type, the pressure is not separated between the high pressure side and the low pressure side of the compressor, so it is necessary to provide a check valve 00) to separate the pressure between the high pressure side and the low pressure side of the refrigerant circuit.

However, by separating the pressure, when the electric compressor (5) is restarted, the compression ratio increases (and the load increases, so it is necessary to increase the output to increase the torque of the electric motor of the electric compressor (5). An electric motor is required for input, which is undesirable in terms of power saving.Furthermore, as a measure to save energy in the electric compressor itself, it is necessary to develop a highly efficient compression section, but development takes a long time. So low torque electric rrIJ
The shortcut is to use J aircraft. For this reason, an attempt is made to save energy by using a motor with a capacity as small as possible to start, but as mentioned above, if the compression ratio at restart increases, the torque of the motor cannot be reduced.

(C) Purpose of the Invention The present invention provides a method for providing a solenoid valve to separate the high-pressure side and low-pressure side of a refrigeration system while the electric compressor is stopped. An object of the present invention is to provide a refrigeration system using an electronic circuit control method, which can sufficiently start up the refrigerator, suppress a rise in temperature inside the refrigerator, and save energy.

B) Summary of the invention The electric compressor and the solenoid valve are configured in parallel circuits controlled by temperature detection type control devices with different operating points, and the electric compressor is started with a delay from the opening of the refrigerant passage of the solenoid valve. The operating point of each control device was set, the solenoid valve closed the refrigerant passage when the electric compressor stopped, and the temperature sensing element of both temperature detection type control devices was shared, and ambient temperature compensation was performed.

(E) Embodiment of the Invention Fig. 4 shows a control circuit, and the same reference numerals as in Fig. 3 indicate the same parts. Figs. 1 and 2 are the same as the embodiment of the present invention, so they can be used as they are. do.

In FIG. 4, (21) is a temperature detection type control device for an electric compressor (5), and a reference input line (Sl) of a comparator circuit (24) having a predetermined differential is connected to a resistor (21).
The proportional output of 5+(26) is connected to the other measurement input line (R1), and the output of the circuit of the resistor 07) and the temperature sensing element (28) is input. (29) is a relay that is excited by the output of the comparator circuit (24), and its switch (29A) opens and closes the energizing circuits of the electric compressor (5) and electric blower (11). (221 is a temperature detection type control device for the solenoid valve (9) and has a predetermined differential (R2) is a resistor.
and temperature sensing element c! The output of the Q circuit is input. (33
) is a relay that is excited by the output of the comparator circuit 00), and its switch (33A) is for the electric compressor (5) and the electric blower (
11) respectively open and close the energizing circuits of the solenoid valves (9) connected in parallel. Temperature-sensing element (for example, inside the refrigerator (first
In the figure, it is installed in the cold air circulation passage (in the freezer compartment), the cold air circulation passage inside the refrigerator, the evaporator (8), or the vicinity of the evaporator, and acts together with the control device (21) to substantially control the temperature inside the refrigerator. good. Furthermore, the operating point at which the solenoid valve (9) of the control device (22) operates to open the refrigerant passage is slightly different from the operating point at which the electric compressor (5) of the control device (2I) is started.
The electric compressor (5) is configured to start with a slight delay after the solenoid valve (9) opens the refrigerant passage. C34) is a temperature sensing element provided to sense the ambient temperature of the storage, and is a semiconductor element having negative resistance temperature characteristics like the temperature sensing element (28).

In this circuit configuration, when the inside of the refrigerator, that is, the freezer compartment (3) is not sufficiently cooled during cooling cycle operation, the output of the comparison circuit (241 (30) is generated and the relay (20
(33) is excited and switches (,29A) (33A, )
is closed and the electric compressor (5) and electric blower Uυ are operating, and the solenoid valve (9) is energized and opens the refrigerant passage.

With this operation, the freezer compartment (3) is cooled down to a predetermined lower limit temperature, and the resistance value of the temperature sensing element (281) increases, so that the potential of the measurement input line (R+) of the comparator circuit (24) becomes the reference input. The potential of the comparison circuit CI!41 drops below the potential of the line (Sl), and the output of the comparison circuit CI!41 disappears, and the relay (29) becomes de-energized, opening the switch (29A) and opening the electric compressor (5).
) and electric blower 01) are stopped. On the other hand, comparison circuit C30
) is also the potential of the measurement input line (R2) of the reference input line (
S2), the output of the comparator circuit (30) disappears, the relay (mower) becomes de-energized, and the switch (29)
A) opens and the solenoid valve (9) becomes de-energized, closing the refrigerant passage. Next, when the temperature inside the refrigerator rises and reaches a temperature slightly lower than the set upper limit temperature, the resistance of the temperature sensing element (28) decreases and the potential of the measurement constant input line (R2) of the comparator circuit (30) changes to the reference input line. (S2), the output of the comparator circuit (30) is generated, the relay G is energized, and the solenoid valve (
9) to open the refrigerant passage. This acts to create a pressure balance between the high pressure side and the low pressure side of the refrigerant passage. Then, when the internal temperature rises and reaches the set upper limit temperature, the resistance of the temperature sensing element (A) decreases and the potential of the measurement input line (R,) of the comparator circuit (24) changes to the reference line (S,
) is higher than the potential of The delay time for the control device (221 If the difference between the detection temperature and the operating point of the control device (21) is within a range from slightly higher than O'C to around 1°C, such a delay time can be achieved.

In this way, the cooling operation progresses and when the set lower limit temperature is reached, the potential of the measuring human power line (R1) becomes lower than the potential of the reference input line (sl) as described above, so the comparison circuit (24)
output disappears, the relay (29) becomes de-energized, and the switch (29A) opens and the electric compressor (5) and electric blower (
11) stops. At the same time, the potential of the measurement input line (R2) of the comparator circuit (3o) falls below the potential of the reference human power line (s2), so the output of the comparator circuit (3(1)) also disappears, and the relay (331) becomes de-energized. switch (33A
) also opens, and the solenoid valve (9) becomes de-energized, closing the refrigerant passage.

In this way, the temperature inside the refrigerator is maintained within the range of the set upper limit temperature and set lower limit temperature controlled by the control device (2υ).The temperature sensing element (34) for sensing the ambient temperature The standard human power line (S2) of the comparison circuit (3o)
). When the ambient temperature is high, the temperature inside the refrigerator also rises quickly. Therefore, it takes a very long time for the solenoid valve (9) to open the refrigerant passage until the electric compressor (5) is started by the temperature control device +W (21). In order to prevent this, the time from when the solenoid valve (9) opens the refrigerant passage to when the electric compressor (5) starts is increased (by setting the circuit operating point to If the ambient temperature is low, the solenoid valve opens the refrigerant passage too quickly, reducing the effect of the solenoid valve (9). However, due to the presence of the temperature sensing element (34), the comparison circuit (3 (1) Reference input line (s2)
The potential of decreases when the ambient temperature is high and increases when the ambient temperature is low, so when the ambient temperature is high compared to the case without the temperature sensing element (3a), the potential of By reducing the potential difference of the measurement input line (R2), the potential of the measurement input line (1, tt) becomes the reference input line (S2).
), the solenoid valve (9) opens earlier, and the time from when the solenoid valve (9) opens to when the electric compressor (5) starts is increased. death,
On the other hand, if the ambient temperature is low, increase the potential difference between the measurement input line (R1) and the reference input line (S2) (to extend the time until the potential of the measurement input line (R2) exceeds the reference input line (S2)). Then, the time when the solenoid valve (9) opens is delayed (so that the electric compressor (
5) works to shorten the time it takes to start, automatically corrects the operating point of the comparator circuit C30) according to the ambient temperature, and starts the electric compressor (5) after the solenoid valve (9) opens. The time required for starting the electric blower θ1) is kept approximately constant. In addition, in terms of the circuit, the temperature sensing elements (28) and (34) may be constructed using those having positive resistance temperature characteristics, and each relay may be replaced with a non-contact circuit. Furthermore, the fan motor for air cooling the condenser (6) may be connected in parallel with the electric compressor (5) (and the present invention can also be applied to a direct cooling type refrigerator).

(F) Effects of the Invention In the present invention, during cooling cycle operation, the start of the electric compressor is slightly delayed from the opening of the refrigerant passage of the solenoid valve, so the startability of the electric compressor is improved and the temperature inside the refrigerator does not rise. It would be possible to suppress the problem to such an extent that there is no adverse effect on the stored material, and to achieve miniaturization of the motor for the electric compressor. -Also, as a temperature detection control method that is cheaper than the time control method, the solenoid valve and the control device for the electric 1111 compressor can both operate according to the resistance change of the JI6 temperature sensing element. Furthermore, stable operation can be achieved that prevents various problems caused by the delay time from the opening operation of the electromagnetic valve to the operation of the electric compressor changing significantly due to changes in ambient temperature, thereby achieving the desired purpose.

[Brief explanation of drawings]

FIG. 1 is a vertical side view of a refrigerator-freezer, FIG. 2 is a refrigerant circuit diagram, FIG. 3 is an electric circuit diagram of the background art, and FIG. 4 is an electric circuit diagram of an embodiment of the present invention. (5)...Electric compressor, (6)...Condenser, (
7)...Reducing pressure equipment, (8)...Evaporator, (9)
...Solenoid valve, 0υ...Temperature detection type control device for electric compressor, (2 hot water...Temperature detection type control device for solenoid valve,
(24) (30)...Comparison circuit, (2 caps...Temperature sensing element, Oa...Temperature sensing element for ambient temperature Applicant: Sanyo Electric Co., Ltd., 1st representative Patent attorney: Shizuo Sano No. Figure 1 Figure 2 Figure 4

Claims (1)

[Claims] 1. In a refrigerant circuit in which refrigerant flows through an electric compressor, a condenser, a pressure reducing device, and an evaporator and returns to the electric compressor, a solenoid valve is provided for opening and closing the refrigerant passage between the condenser and the pressure reducing device. The electric compressor and the electromagnetic valve are controlled by temperature detection type control devices having different operating points, and these control devices start the electric compressor with a slight delay from the opening of the refrigerant passage of the electromagnetic valve. Both controllers are equipped to control the temperature inside the refrigerator, and both controllers have a comparison circuit that generates an output by comparing the potential that changes based on resistance changes of a common temperature sensing element with a reference potential. In addition, the reference potential circuit of the temperature detection type control device for a solenoid valve includes an ambient temperature sensor that corrects the opening point of the solenoid valve to be earlier when the ambient temperature is high and to delay the opening point when the ambient temperature is low. A storage room equipped with a heating element.