JPS60185076A - Refrigerator with electric expansion valve - 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] (Industrial Application Field) Kimitsuaki 1. Regarding the L refrigerator, in particular, the expansion mechanism is
This invention relates to an improvement in a device equipped with an adjustable electric expansion valve.

(Prior art) Conventionally, a refrigerator for this scale, for example,
As disclosed in Japanese Patent No. 8 47628, a thermoelectric electric expansion valve whose opening degree can be adjusted is equipped with a detection means for detecting the degree of superheat of the refrigerant at the outlet of the evaporator, and a sensor for receiving the signal of the detection means. , a control means for controlling valve spacing of the electric expansion valve according to the degree of superheating (↓), and the degree of superheating of the refrigerant is maintained at a predetermined value by controlling refrigerant diversion of the electric expansion valve. It has been known.

However, for example, when operating in various operating modes, such as during cooling operation, heating operation, or when the same operating state -(゛even if the number of rooms with air conditioning is increased),
, 1. In the above-mentioned conventional type (J, operation mode), the initial valve opening of the electric expansion valve is -t''! Since C1 is fully closed at C1 and is at a position far away from the appropriate valve opening at stable operation depending on the subsequent operation mode, an increase in the valve opening of the controlled electric expansion valve during operation. Since the width is large, it takes a relatively long time to stabilize the valve opening to the appropriate degree, and the early stability of the refrigerating capacity is lacking.

(Objective of the Invention) In view of the above, the present invention provides an electric expansion valve that can relatively easily control the valve opening. Focusing on the fact that there is a stepping motor type that has a 1:1 ratio of 1:1 to 1:1, our aim is to use the electric expansion valve described above, and to use the electric expansion valve when starting operation in various operation modes. The valve opening of the expansion valve is initially set to the appropriate valve opening corresponding to the operating mode at startup, which is determined in advance by tests etc. prior to operation. - The purpose is to reduce the range of increase/decrease in the valve opening of the electric expansion valve to achieve stable convergence to the appropriate valve opening in a short time and in a good manner during operation in any operation mode C.

(Structure of the Invention) In order to achieve the above object, the structure of the present invention is as shown in FIG. 4. Degree of superheating of the refrigerant after passing through. L supercooled u
Detection means (55) for detecting II sadness, and the detection means (55)
5) control means (56) for receiving a signal from the heat exchanger (3) and controlling the valve opening degree of the electric expansion valve (Vl) according to the degree of superheating or subcooling of the refrigerant; In a refrigerator configured to maintain the superheating degree or subcooling degree at a predetermined value, an operation start time detection means (57) for detecting when the refrigerator starts operating is used to determine the operating mode of the refrigeration mode. -C according to the mode determination means (58) and the operating mode of the refrigerator.
A storage means (59) for storing in advance the initial IUJ setting value of the electric expansion valves (V1 to V4) and No. 1.1 of the operation mode determination means (58) are used to determine the initial setting value according to the operation mode. The readout means (60) from the storage means (59) and the signal from the start-of-operation detection means (57) are received () to open the electric expansion valve (Vl-V4).
Q is located at the initial setting value read out by the above-mentioned reading means (GO>) (=1 minus initial setting means 61). When the machine starts operating, the first 1! The initial setting is set to the initial setting value of 110.

(Effects of the Invention) Therefore, it is possible to use a J
:Re(, at the start of operation of various operation modes C of the f1 refrigerator,
The valve opening degree of the electric expansion valve was read out by the reading means. Initial %+ corresponding to the current driving mode! 1 + stitch■
1- Ri+ 1111 W roll λ h 6 small T Ka 1
14 dll Yasu; Hoyu - Operation in 7 mode - Even in 1, reduce the range of increase/decrease in the valve opening of the control lever electric expansion valve during operation, and switch to the operation mode of the electric expansion valve. Convergence control to the appropriate valve opening of 1 can be performed in a short time with a good Cθf, thereby improving the convergence stability of the valve opening and effectively stabilizing the frozen 1j deer at an early stage. It is.

(Example) Hereinafter, an example of the present invention will be described based on the drawings below in Figure 2.
It will be explained in iTman II.

Fig. 2 shows an embodiment in which the present invention is applied to a pump-type air-conditioning/heating/hot-water supply system, in which (△) is an outdoor unit installed outdoors, (B), (C) .

(D) is an in-kiln unit disposed in a different room in the room, ([3] is a hot water storage tank), and the outdoor unit 1-(A) is compressed (some 1) and the heat source side heat exchanger (2), and the indoor units +- (B), (C), (D>) are empty inside, and the ilV load side heat exchanger ( 3).

It is equipped with (4) and (5). In addition, hot water tank Koni 1~
([) is a hot water storage tank (6) that stores water inside, and the hot water storage l! A hot water supply load side heat exchanger (7) that heats the water stored in l1 (G), and a pump ([]) that circulates the stored water in the hot water storage tank (6) to the hot water supply load side heat exchanger (7). It is equipped with

J3 is in the outdoor unit (△) above, (SVl)J>
J, and (SV2) are four-way switching valves that switch as shown by solid lines when OFF, and four-way switching valves that switch as shown by broken lines when ON, respectively. (S'V3) is a heat exchanger that is supplied from the receiver (8) 4) Directly opposite side heat exchange +l, il\f to accommodate the refrigerant flow to the vessel (7)
4k Itl m bu↑, (V+ >, (V2 >,
(■3 >.

(V4) and (5) can be opened/closed and the intensity can be adjusted 0
Each electric expansion valve (1) to (V5) is a stepping motor type electric expansion valve, and each of the electric expansion valves (1) to (V5) receives a valve opening control signal that is generated by a CPU (!12) which will be described later. This corresponds to the pulse number of the driving pulse as 1:1.

In addition -C1 (T +-11>) is the electric expansion valve (\/
4> and the liquid pipe between the receiver (8) 15) and the compressor (
1) with the return gas pipe (23).The first bypass envelope with the capillary tube (27) interposed
36), which is a first temperature sensor consisting of a thermistor provided on the return gas pipe (23) side of the capillary tube (27), and is configured to control the evaporation temperature (1°
1) is detected after (T I-12>
is the ζ gas pipe (16) between each air conditioner load side heat exchanger (3)/(5) and the four-way switching valve (SV2) and each of the above
fiilIIJ expansion valve (V+).

(V2) ,, (V3 > indoor unit (B),
(C), (D) side branch liquid piping (20), <21).

(22) Which spaces should be connected? The auxiliary condenser (37), the auxiliary condenser (37), and the check valve (38) are connected to the second bypass pipe (39) with fPrQ.
) and the sharp tube (28), the air conditioner load-side heat exchanger (3) during heating operation.

This is to enable the condensation temperature (T2) of (4) and (5) to be detected outside the room, and < T I-13) ~
(Tl-110> are the third to tenth temperature sensors which are respectively thermistors as above, and the third to fifth temperature sensors
Temperature sensors (T)-13) to (TI to 15) are removed, and air conditioning load side heat exchangers (3) to (5) are four-way IJ.
J'A valve (S V 2 > 1771 (1) Branch waste distribution 'i'l ('I7) ~ (1) stage (), air conditioning operation port) and low pressure gas cold sluice during cooling mud supply operation It detects the refrigerant humidity (-r:+), (T4), ('T5) of 6th to 8th &.

11 centimeter (T H6) to <Ding ['8) are each air conditioner Cq i? ii side heat exchanger exchange) ~ (5) and receiver (
It is installed in the branch liquid piping (20) to (22) between (TI), (8), and the 9th degree ren'no (
T l-19) (Return gas piping (2) to J compressor (1)
3) is used to detect the refrigerant temperature (T9), and the (Ou HIO) is used to detect the discharge waste piping (2/I) of compression 1 (1).
) to detect the refrigerant) B polishing (-r 10 ).

Therefore, when the air conditioning load side heat exchangers (3) to (5) each act as an evaporator, the first temperature sensor (T
I-11), the evaporation temperature (T1), d3J, and the third
~5th temperature lens (TI-13> to (TI-15)
) by each air conditioner negative? 'i? J-side heat exchanger (3) to 5
) Refrigerant temperature of low pressure gas refrigerant (T3), (T.

1), (T5) is detected, and conversely, each air conditioner's
Exchange 2:: When (3) to (5) act as a condenser,
λ rice dampening (T2) is applied to each of the air conditioning load side heat exchangers (3) to (5). ) The refrigerant temperature (T6') of the high-pressure liquid refrigerant after passing through it.

(TI) and (Ta), and when the heat source side heat exchanger (2) acts as an evaporator, the first temperature lens (TI-11) detects the evaporation temperature (TI). Detect the refrigerant temperature (T=1) of the low-pressure gas refrigerant after passing through the heat source side heat exchanger (2) at the 9th wet sensor < T I-19'). I'm doing it. In addition, in the figure,
(29) is a capillary duplex, <30) +, j one-way valve that allows refrigerant to flow from the supply/cooling load side heat exchanger (7) to the receiver (8), (31) +Σ1 Ani1 combulator, (,32) to (35) I; are closing valves.

1. 1. 1. 1. 4. (T I-
11) To (TI-410), install the above-mentioned four-way steering valves ↑ (SVI), (SV2>) and electric picture/on-off valve (SV3) as well as shown in Fig. 3. 5 electric expansion valves (Vl
) - (v5) to the control circuit (40) that controls η. -C3
The control circuit (40) is connected to the transmission/reception function of the
is shown in Figure 3. 1J3J;
temperature sensor (T111) ~ (T I-1'10
) selectively receives the temperature signal from the three indoor units (B
) to (D) for cooling a3 and heating each) car lIl/
i command signal.

Receives the set room temperature signal, the actual room temperature signal, and the heating operation command signal from the hot water storage tank -7 Nij-<E) C1''U
('12), various operation t--codes such as the type of operation command No. 18 and the number of operations (number of operating rooms) of indoor units (B) to (D) for the h1 movement 11 of the compressor (1). Be sure to be appropriate depending on the situation! Please note the above 4f17t1 ° electric expansion valve (V'
It is equipped with a ROM (43) that stores in advance the first (υ) stage setting 111 for the first (υ) step (to N/(V4)).

Therefore, the CPU (42>) is connected to the three indoor units 1 to 4.
The cooling or heating operation command No. 13 from (B) to (D), the actual room temperature signal, and the hot water supply operation command signal (please refer to
>Uτ
S, V 2 ), electric m Ijtl valve closed (SV3) i
t>, I, 4 electric expansion valves (Vl)~kuv7'I>
During cooling operation, it is controlled as shown in the first row of the same table, and a signal is emitted during operation.
) 11 is referred to as the operation side) to the air conditioning load side heat exchanger (3) - (5) heat absorbed from the room is transferred to the heat source side heat exchanger (2).
) while heating the corresponding indoor area) 1), each air conditioning load side heat exchanger (3) which operates with the evaporator door mentioned above.
(5) The degree of superheating of the refrigerant, that is, the difference in refrigerant temperature (T
3-1-+), (T4-T+), (
Electric expansion valve (\/1) corresponding to T5 - T1)
) ~ (v3) Set overheating If ('S l-1o +
), the cooling supply (during easy operation, control as shown in the second row of the same table) and the air conditioning negative 11 side heat exchanger (3) on the C1 operation side.
In (5), the heat Irl absorbed from the room is radiated to the water stored in the hot water storage tank (6) by the hot water supply negative front heat exchanger (7), and the stored water is heated (hot water supplied) to the corresponding room. Air conditioning load side heat exchanger (3) that cools the room and simultaneously acts as the evaporator.
The degree of superheating of the refrigerant in (5), that is, the degree of cooling 11) One round difference (T3-1'+), (T4-1).

The superheat degree (Sl-1o2) is set using the electric expansion valves (vl) to (V3) corresponding to (1゛5 to 1) in the same way as above.
), and for easy hot water supply operation, control is performed as shown in the third stage in the same table, and the heat exchanger (2) on the heat source side absorbs heat from the outside, and the heat amount of the saw is transferred to the heat exchanger (7) directly opposite the hot water supply. Saving) Easy ++V (G)
The heat exchanger on the heat source side, which acts as the evaporator while supplying hot water by dissipating heat to the stored water inside the tank, causes the superheating of the refrigerant in pitch black (2), i.e., the difference in refrigerant temperature p1 (-1-9-T+). to the set superheat degree (S11o3) using the electric expansion valve (v4); l! In addition, during heating operation 11.5, control is performed as shown in the fourth stage of the same process. In (5), heat is radiated into the room to heat the room, and the temperature difference ('T' 9-1-+) to electric IIj, 3
Adjustment to the set superheat degree (St-1o4) with the tension valve (V4) and overcurrent of the refrigerant in the air conditioning load side heat exchangers (3) to <5)C, which are operated by the above-mentioned condenser, etc. degree, that is, the temperature difference in refrigerant temperature (T2-Tr), <T2-T7)
, deviate from (l-2-1-8) and go to the corresponding electric expansion valve (vl). (V3)-C setting is too high.
S C1] K adjustment tool.

In addition, operation f and Bij stop during heating are determined by each unit 1 to (
B).

(C), each indoor fan (3a) installed in (1).

(4a), <58) is performed by stopping η.

This j4 case, stop side air conditioner negative 1', η side heat exchanger (3)
.

The amount of heat dissipated in (4) and (5) is the fourth (lower, so the electric expansion valves (■1) to (3) are fully closed (L), and the set degree of supercooling (SCO2) during heating operation is set. In particular, it is possible to control the heating capacity to a degree that does not pose a practical problem, while also preventing liquid pooling as much as possible. In Fig. 3, (15) to (49> are drivers for driving the five electric expansion valves i' (Vl) to (V 5 ), respectively, (50) l and CPU (4, 2). 6Q valve (Vl
-) to (＼15) Valve opening control (1) to distribute the drive pulses (after) to the corresponding ones, (51) The low gas indicator light (1'>2) is the power plug. The electric expansion valve t-(\/5) is an expansion valve for pressure equalization that balances the pressure between the high pressure side and the low pressure side of '(1). It works very well.

Next, 4 +lI by CrLJ (42) above! l's electricity! I! The valve opening control of the JJ expansion valves (vl) to (\171) will be explained based on the chart in FIG.

In addition, heating operation 11, above, four electric expansion valves (Vl)
Since the valve opening degree of all of the valve openings of ~.(\/4) is controlled as shown in the table above, and the entire control of this embodiment can be explained, the flow during the heating operation will be explained below. This flowchart 1~ receives a heating operation command signal from at least one of the three indoor units and performs a C start. First, in step S1, among the three indoor units (B)~ (D> After determining the driving mode based on the driving command No. 111 received from at least one vehicle and the number of received driving commands, step S2
, a drive pulse such as a valve opening control signal is generated in the direction of closing the opening of the four electric expansion valves (Vl) to (V/I), and each of the electric expansion valves (Vl) to (■ 4) Position the valve at the 11i base semi-position while the valve opening is fully open. Then, in step S] 43, each electric expansion valve (vl) to (v
4) Read the initial setting value of the valve opening degree, and apply the driving mh pulse of the number of pulses according to the opening degree difference between the first 1IIJ setting 11'1 and the 11th degree reference position to the corresponding electric expansion valve r( vl
) to (V71') to control the JT melon to each initial setting of 1 white. Then, in step S a, an instruction is given to maintain this valve opening for a predetermined time (e.g., 5 minutes) corresponding to the transient time until the operation becomes stable, and then in step Sst', the compression is performed for the first time. Start Iku (1).

Next, in step S6, 10 humidity hinges ("
Based on the temperature signals from r H1) to (T I-110), the temperatures at 10 locations in Figure 2 (1-+) to (T 10
) is exposed 15, and compressed 1 in step S7.
; Compare the refrigerant gas discharge temperature (Too> of height (1)) with the specified ship (TcM) corresponding to the abnormal rise, and determine that the specified 1 [1'J (T E M ) J, too large YES
6I: During operation, in step 88, the setting superheating point (SHo4) corresponding to the operation mode is lowered to avoid a drop in the refrigerant gas discharge temperature (TIO), and the temperature is set for a predetermined period of time until this state becomes stable. While the process proceeds to step S9, the refrigerant gas discharge tili (Too) is adjusted to a predetermined value i:ri ('T-
EM) If the following No is the case during normal operation, the process immediately proceeds to step S9.

Therefore, in step S9, the actual degree of superheating (S
H) is excluded based on -1 - recorded humidity difference (T9 - T+)
The air conditioning load side heat exchanger on the operation side and the air conditioning load side heat exchanger on the stop side (3) act as condensers.
) to (5), the actual degree of supercooling (SC) is expressed as the humidity difference (
-r2-Te).

<1"2-Ty), (T2-Ta>), the actual superheat degree (S
I−+>a; and the actual degree of supercooling (SC) are compared in size with the corresponding set degree of superheat (SHoa) 713 and set degree of supercooling (SCo+−·, 2). Soshi-
In the case of N and O, which do not match each other, the process proceeds to step So, and in step So, the actual superheat degree (S l-1> corresponds to the set superheat degree (Sl-1 o4
) or when the actual degree of subcooling (SC) is greater than the set degree of supercooling (SCol~02), it is determined that the refrigerant flow rate is small and the corresponding ￥i dynamic expansion valve ↑ ( While the number of pulses for vl) to (V4) is output as jt) and a driving pulse as Er (Er) to increase the valve opening, conversely, the actual degree of superheating (St~1) If J5 and actual subcooling degree (SC) are 6 less than the corresponding set superheating degree (S l-1o4), the setting overcurrent MI19
If it is smaller than (SCo + ~oz), it is determined that the refrigerant flow rate is large and the corresponding electric expansion valve (Vl) is activated.
After reducing the number of pulses to (V/I) and outputting the drive pulse of C to reduce the valve opening time,
Proceed to step SI2. On the other hand, in step S10, the actual superheat degree (SII) and the actual overvoltage (SII) are determined.
C) Setting value (SHo a ), (
If YES, which is equal to SCo + "o 2 ), it is determined that the refrigerant flow m is appropriate, and [immediately step S1
Proceed to step 2.

Subsequently, in step S12, the valve opening degree of the electric expansion valve (V4) which is in the process of controlling the degree of superheat is determined, and if the answer is No that it is not fully open, it is determined that the degree of superheat is being controlled appropriately, and ζ step S. Return to r, while the valve opening is fully open YES
In the case of 11. the degree of superheating is low and there is insufficient refrigerant scum.
'i (lack of gas IL'+) rIf you judge that there is,
Proceed to Sfutsubu S 13. And heating operation +1. 'l
First of all, indoor units 1~([3)~<
D >``(') It is determined whether the -C sword gap has occurred due to the accumulation of ``('), and the heating is stopped in step S15 by d3 (111'l (1)'', i! inside 1' day l
-([3)~(D)'r setting overvoltage 7JII (S
Co,! ), lower this phantom response tl' le electric f
Start collecting the accumulated refrigerant by opening the ar expansion valves (Vl)-(V3) to a predetermined degree or more. Then, after waiting for sufficient time to recover, the electric motor 1 controlling the corresponding superheat degree (81-104>) in step S IG changes the valve opening 1 of the tension valve (V 4 ). Judgment: 1. If the answer is No, the degree of superheating has returned to proper control [!7
i L (Returning to S6 S6, Y still at full throttle
In the case of E S L)), it is determined that there is a gas shortage, and the operation of the compressor (1) is stopped in step S14 (43), and the gas shortage indicator lamps (5) are turned on in step S14.

On the other hand, in the case of cooling operation (step S+++-4), the operation of the compressor (1) is immediately stopped and the out-of-gas indicator light (51) is turned on.

(;(The room on the front side = 1 day!)
]), when a new heating operation command signal is received, the process proceeds to the flowchart of FIG. 5 which interrupts flowchart 1- of FIG. Step S+s '71'' After deceiving the number of driver's cabins and determining the driving mode, use Suj' Tsubu S19 to read the initial limited 1st shift of Fin Maro according to the driving mode determined above from the ROM (43). When read out, the air conditioner negative 6 side heat exchanger 1!/! unit (3) that is about to start operation anew
~(5) l: Compatible Lilden! r! JI expansion valve (V
1) Set the valve opening degree of −<V3) to the above initial setting (10). Then, instruct the valve opening degree to be maintained for a predetermined period of time during which the refrigerant flow is stabilized. Return to the tube S6 in FIG. 4.

Therefore, step 8 of 71-1 to t--1- in FIG.
9. During heating operation, the degree of superheating (S1) of the refrigerant after passing through the heat source side heat exchanger (2), which acts as an evaporator, is detected based on the humidity difference (T9-T1). , Air conditioning load side heat exchanger 1 used as a condenser! /! Vessel (3
), 1. ), (5) What is the subcooling degree (SC) of the refrigerant after passing through? :, (-r2 Ts>.

(-[2-T7) and (T2-Ts), a detection means (55) has just been completed.

In steps Sho and 511 of FIG. 4, the actual degree of superheating (S l-1
>, 13 and operation side air conditioning load side heat exchangers (3) to (5
) The actual hot water cooling u1 degree (SC) is the setting superheat L
(1 (S Ho , t ) and set overcurrent 1111 (
The temperature difference between the refrigerant temperatures (1゛9-K1) and (T, + -T6) becomes equal to S Co + ).
, (1-2-, 1-7>.

Corresponding electric expansion valve (Vl) according to (King 21-a) ~
Control means for controlling the valve opening degree of (v4) 5G
). In addition, three indoor units (B) ~
The operation command signal from at least one of the (I)
When the PU (42) receives the signal, the flowchart shown in FIG. 4 starts, thereby configuring a first stage (57) for detecting the start of operation of the refrigerator. At the start of operation of this refrigerator, that is, if the flowchart h in Fig. 4 (Start 1 -
The operation mode determining means (58) for determining the operation mode of refrigeration proceeding to +/υ is comprised of +71S.Furthermore, the ROM 13 of the control circuit (40) contains J, S, Refrigeration. Electric 1113 tension valve (
tj4 comprises a storage means (59) in which initial jQ constant values of Vl to V4) are stored in advance. In addition, after step S1 of FIG.
8〉H,,,'i);, a3 is placed in the first stage of step S3 and the first ill]gQdetermined) is executed according to the operation mode.
[RO'M(43) (7th memory stage < 59)) l
)) ra readout JJ: The sea urchin readout means (60) is formed as )II3, and step S3riF
Processing in stage I #h 4'+ 1 (proceeds to the subsequent stage, and electric expansion valves (Vl to V
4) in step S3' (reading means (
60)) The first I that corresponds to the operation mode read by I] The initial setting means (61) is configured such that the setting 1111 has a position.

Therefore, in the embodiment described in -, when the refrigerator starts operating, the Smeer rubbing seven-tar type electric expansion valve (vl) ~, (V/I) (L, The valve opening of the electric expansion valve (3L, initially I (
If it is in the il position, d3 at the start of operation, the operation stability in that operating mode 11) The proper valve will be opened 1 force (equal to the force ζHJ. As a result, the electric expansion valve t Regardless of the operating conditions, the valve opening of 713 will converge to an appropriate valve opening and will converge and stabilize well at 0 hours C. Therefore, the convergence stability of the valve opening will be improved. Early stabilization can be achieved effectively.

In addition, in the embodiment 1-, the electric expansion valves (\/1) to (v4
), the initial setting of the electric expansion valve (V
Of course, even if the valve opening degrees of (1) to (V4) are changed and replaced with (i), it is possible to do so. In this case, during the next drive! If1 simply says “!TffiL11
1X<I! [Iya〆\/1) ~ (\/A)'s I f1m+
The 1111Aft constant of y'r is determined by Step S in Figure 6.
As in '3 < 1) 0 operation stops l, - is stored in a3 and - (is performed at the current valve opening), so the convergence to the appropriate valve opening is stabilized. J, it can be done in a short time.

j, T, In the above example, while the refrigerator is operating! Ifin
'r, superheating degree or overcurrent 11 +U control 1ll-reverse electric motor 111i' tension 5r (\/1) ~ (V4) -11 valve opening is fully closed, position is good. I was in position, but instead of Dere, I got 1 Ryo while the bu↑ Kaima was at full throttle! ! in semi-position (
1' / It is of course possible to do so, but during operation, it is necessary to control both overvoltage and overvoltage, and it is necessary to control either one of them. Only r Shi J,
stomach.

Furthermore, in the above i11 Example C, 113 is applied during heating operation! When the electric expansion valve T' (V4) under lj control is fully open, the inside of the dormitory on the stop 1 side - to the l unit ([3) - <[]
The electric expansion valves (Vl) to (V3) corresponding to I did it, but
In addition to the above-mentioned stop side 〒〒〒unit〒〒〒〒〒〒〒〒〒〒〒〒〒〒〒〒〒〒〒〒〒〒
) to the electric motor corresponding to 3=l; Zhangbui (V 1 ) ~(
V 3 ) (a lll1 > LI) The refrigerant may be forcibly opened fully during the period of [reservoir I] [Recover refrigerant J: Sea urchin may be used.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing the configuration of the present invention, Figs. 2 to 6 show embodiments of the invention, Fig. 2 is a refrigerant piping system diagram when applied to a 13L air-conditioning/heating water heater, and Fig. [,L
The internal configuration of the control circuit is shown in the electrical circuit diagram, and Figures 4 and 5 respectively show the operation of the CPU.
FIG. 6 is a 1-chart diagram showing a modification of the operation of cr-'u. (V1~v/I)...Electricity! PII expansion valve, (2~5
) =-heat exchanger, (55)... detection means, (56)
...control means, (57) ...operation start detection means,
(58) ... Luck'/i t-do judgment means, 59)
... Storage means, (60) ... Reading means, (61
)...Initial setting means. 1st mouth Figure 6 Figure 5

Claims (1)

[Claims] (1) Electric expansion valves (Vl to V4) whose opening degree can be adjusted; detection means (55) for detecting the degree of superheating or subcooling of the refrigerant after passing through the heat exchangers (2 to 5); Detection means' (55)
control means (56) for receiving a signal from the heat exchanger (2 to 5) and controlling the valve opening degree of the electric expansion valve (V1 to V4) according to the degree of superheating or subcooling of the refrigerant; ) to maintain the degree of superheating or subcooling If of the refrigerant at a predetermined value. an operation mode determination means (58) for determining, a storage means (59) for storing in advance the initial settings of the electric expansion valves (V1 to V4) according to the operation mode of the refrigerator, and the operation mode determination means (5B). ) reading means (60) which receives the signal of the operation mode (according to the operation mode) and reads out the fixed value of i1 from the register (59); The electric expansion valve (V1~
initial setting means (6) for positioning the valve opening of V4) at the initial 11J set value read out by the reading means (60);
1) Refrigeration equipment equipped with an electric expansion valve.