JPS62141472A - Heat pump device - 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] The present invention relates to a heat pump device in which an electric refrigerant flow control valve that controls the refrigerant flow rate by an electric signal is provided in a liquid refrigerant path forming a refrigeration cycle. be.

[Prior Art] A compressor that sucks in refrigerant gas, compresses it, and discharges it, a four-way valve that switches the refrigerant circulation direction, a user-side heat exchanger that uses a fluid that has undergone heat exchange with the refrigerant, and a special A refrigeration cycle is formed by a heat exchanger on the non-use side that exchanges heat between a fluid that is never used and a refrigerant, and a single device can optionally perform both cooling and superheating of the fluid on the use side. In heat pump devices that can be used interchangeably, improvements in reliability have been pursued in addition to energy savings, and in place of the conventionally used mechanical expansion cells and capillary tubes as refrigerant flow control means, more precisely Electric cold flow control systems have come into use that enable control.

FIG. 4 is an overall configuration diagram of a conventional heat pump device that controls the flow rate of cold tofu using such an electric flow 171 control block. ) is a switching valve, also called a four-way 5t, that switches the flow path of the refrigerant gas discharged from the compression a(1)!, IJ, (
3) is a user-side heat exchanger (hereinafter referred to as a heat exchanger) that exchanges heat between the cold gas sent from the compressor (1) and the user-side fluid, and (4) is also a compressor. Non-use side heat exchange a (hereinafter referred to as heat exchanger), which exchanges heat between cold gas sent from m(1) and non-use side fluid such as outdoor air, (5) is heat exchange Vessels (3) and (4)
An electric refrigerant flow control valve (hereinafter referred to as "control valve"), which is installed in the cold flow path connecting the high-pressure refrigerant to low-pressure cold flow, and adjusts the cold flow to change the high-pressure refrigerant into low-pressure refrigerant.
5a) is an electromagnetic coil that drives the flow j11 control valve (5) to determine the valve opening, and (8) is an accumulator that separates liquid refrigerant and gas refrigerant and causes only gas refrigerant to be sucked into the compressor (1). , (7) are fans (21), (22) that feed the unused fluid to the heat exchanger (4).

(23) is a user-side refrigerant temperature detection device, a non-use-side refrigerant temperature detection device, and a suction refrigerant temperature detection device (hereinafter simply referred to as temperature detection devices), which are closely fixed to the refrigerant pipe, and (24) is a temperature detection device. Devices (21), (22)
, (23) is a control valve driving output value calculation means for calculating the output value of the flow rate control valve (5), that is, the flow rate of chilled tofu so that the temperature difference is maintained within a certain range, based on the detected temperature of (23); Based on the calculation result of the valve drive output value calculation means (24), a current corresponding to the control valve output value is caused to flow J1i control gor(5
) is a control valve drive output means that controls the valve opening degree by flowing it through the electromagnetic coil (5a) of the valve. In addition, the solid arrow on the refrigerant feed path indicates the direction of cold tofu circulation during heating operation to heat the fluid on the user side.
The dotted arrows each indicate the direction of circulation of the cold tofu during cooling operation to cool the fluid on the user side.

With the configuration described in , during heating operation, the high temperature and high pressure cold gas discharged from the compressor (1) is supplied to the heat exchanger (3) via the switching valve (2), and heat is radiated to the fluid on the user side for heating. It liquefies at the same time it heats up. This liquefied cold tofu is stored at the flow control valve (
5) to become a low-temperature, low-pressure gas-liquid mixed cold mixture, which then flows into the heat exchanger (0) and absorbs heat from the unused fluid supplied by the fan (7) and vaporizes. The cooled gas flows into the accumulator (6) via the switching valve (2), and the remaining liquid refrigerant that has not been completely vaporized in the heat exchanger (4) is distributed here, and only the low-pressure gas coolant flows into the compressor. (1) is inhaled.

In addition, when the temperature of the air as the non-use side fluid is low during the heating operation, moisture in the air adheres to the heat exchanger (4) in a cylindrical shape, and when frost formation 1i) increases, the specified heat exchange I can't get sex anymore. Therefore, the frost is removed by switching the switching valve (2) for a short period of time. Perform so-called defrosting operation. During this defrosting operation, the high-temperature, high-pressure cold gas discharged from the compressor (1) is supplied to the heat exchanger (4) via the switching valve r (2), and the frost that has arrived there is radiated and removed. It liquefies at the same time as frosting. Hereinafter, the cold tofu passes through the flow control valve (5) (at this time, the flow control valve is fully open) in the opposite direction to the path described above, and then flows into the heat exchanger (3). It absorbs heat from the user fluid and evaporates. Further, the vaporized gas coolant flows into the accumulator (6) via the switching valve (2), and is then sucked into the compressor (1).

On the other hand, during the cooling operation, the high temperature and high pressure cold gas discharged from the compressor a (1) is liquefied in the heat exchanger (4), and the pressure is reduced by the flow rate control valve (5), just as in the defrosting operation described above. Next, the heat exchanger (3) absorbs heat from the utilization fluid, cools it and vaporizes it at the same time, and returns to the compressor (1) via the switching valve (2) and accumulator (6).

In a heat pump device that switches between heating operation and cooling operation as necessary, as shown in the following, even if the fluid temperature on the user side and the fluid temperature on the non-user side change, the compression a
Return to (1) The flow control valve (
5) Adjust the valve opening to improve the refrigerant flow! I need to adjust the shadow.

For this reason, for example, during heating operation, the temperature of the low-pressure gas-liquid mixed refrigerant that has passed through the flow control valve (5) is measured by the humidity detection device (2
2) The temperature of the cold gas flowing out from the heat exchanger (4) is detected by the temperature detection device (23), and the control valve drive output image calculation means (24) calculates the detected temperature difference. The output (if) that can suppress the output within a certain range is calculated, and the electromagnetic coil (
The jt opening degree was adjusted by changing the current flowing through 5a).

This means that the refrigerant that has passed through the control valve (5) is a low-temperature, low-pressure, gas-liquid mixed refrigerant, and is in a complete two-phase state, so the chilled cooper temperature is the saturation temperature of the refrigerant pressure. There is. Further, the refrigerant flowing into the heat exchanger (4) gradually vaporizes and reaches the outlet 1-1 of the heat exchanger (4) with a pressure drop. Therefore, by assuming the pressure loss of the heat exchanger (4) and detecting the refrigerant temperature with the temperature detection device (23), it is possible to determine the amount of superheat of the cold tofu gas at the outlet of the heat exchanger (4). Temperature detection device (22)
, by controlling the temperature difference obtained in (23) within a certain range, only the low-pressure gas refrigerant having a predetermined amount of superheat can be transferred to the compressor (1).
) is nothing more than 1- inhalation.

On the other hand, during cooling operation, the heat exchanger (3) serves as a low-pressure side evaporator, so the deviation between the temperature detected by the temperature detection device (21) and the temperature detected by the temperature detector (23) is -. The refrigerant flow rate is controlled to remain within the range.

[Problems to be Solved by the Invention] In the conventional heat pump device described above, the amount of superheating of the suction gas refrigerant to the compressor (1) was controlled based on the chill temperature detection (fi) of each part. For example, when the fluid temperature on the user side is low during heating box rotation, the high pressure honeycomb will be low, and the temperature detected by the temperature detection device (22) will be low, making it necessary to adjust the valve opening of the flow rate control valve (5). As a result, there was a problem in that the capacity of the compressor (1) was significantly reduced.

In addition, since the amount of superheating of the suction gas refrigerant to the compressor (1) is controlled, high compression ratio operation is possible under conditions where the temperature of the fluid on the user side increases and the temperature of the fluid on the non-user side decreases. In this case, the temperature of the gas refrigerant discharged from the compressor (1) became abnormally high, and the lubricating oil inside the compressor (1) was carbonized. There have been problems in that it causes slippage and overheats the compressor drive motor, reducing the lifespan and reliability of the compressor.

Furthermore, depending on the detected temperature of the gas refrigerant sucked into the compressor (1), the flow jij is controlled, and if the opening of the control valve (5) is adjusted, the flow of chilled tofu is adjusted by adjusting the valve opening. Since the change in temperature causes a change in the temperature of the gas refrigerated tank again, the operation is difficult to stabilize, and there is also the problem that the first control valve (5) frequently opens and closes.

This invention was made to solve this problem, and even when the temperature of the fluid on the usage side and the fluid on the non-use side fluctuates, the operating condition hj of the compressor can be maintained in a good condition, and
It is an object of the present invention to provide a heat pump device that can prevent a flow-ji1 control block from opening and closing unnecessarily frequently, thereby improving the reliability and extending the life of the entire device.

[Means for Solving the Problems] The heat pump device according to the present invention has first, second, and third temperatures for detecting the temperature of the compressor discharge refrigerant, the temperature of the fluid on the utilization side, and the temperature of the fluid on the non-utilization side, respectively. a detection device;
Based on the detected temperatures of the second and third temperature detection devices, 1i,
Whether or not the detected temperatures of the first calculation means for calculating a control valve drive output reference value for setting the quantity control valve to a reference opening degree, and the second and third temperature detection devices each exceed a predetermined range. a second calculation means for determining the temperature, and calculating a control valve drive output correction value based on the detected temperature of the first temperature detection device to correct the control valve drive output reference value when the temperature exceeds a predetermined range; We are prepared.

[Operation] In the present invention, the control valve drive output reference value calculated by the first calculation means based on the usage side fluid temperature and the non-use side fluid temperature detected by the second and third temperature detection devices is used. By controlling the opening degree of the flow rate control valve and suppressing the valve opening degree from becoming extremely small in response to changes in the fluid temperature on both the use side and the non-use side, a decrease in compressor power is prevented.

In addition, the second calculation means corrects the control valve drive output 1 (quasi-setting) based on the discharge refrigerant temperature of the pressure-fi machine detected by the first temperature detection device, so that it is possible to compensate for a wide range of changes in temperature conditions. To prevent abnormal overheating of the compressor discharge chilled temperature 1
1-I'm sitting.

Furthermore, only when the temperature of the utilization side fluid and the non-utilization side fluid exceeds a predetermined temperature range, does the second calculation means control the control valve drive output group? (Since the li value is corrected, the number of opening and closing operations of the flow rate control valve can be significantly reduced compared to correcting the temperature range without setting it once.

[Embodiment] Fig. 1 is a block diagram of an embodiment of the present invention. In the figure, (1) to (7) are completely the same as the conventional device shown in Fig. 0'54. Other than (11), (12)
.

(13) is a user-side fluid temperature detection device, a non-use-side fluid humidity detection device, a compressor discharge cold storage temperature detection device (hereinafter referred to as temperature detection device 1-1'), and (14) is a temperature detection device, respectively. Control j that calculates the drive output reference value of the flow control valve (5) based on the detected temperatures of (11) and (12)
1 drive drive output correction value calculation stage, (15) is a temperature detection device (
11), (12), and (13) are control valve drive output correction value calculation means for calculating the drive output correction value of the flow control valve (5) based on the detected temperatures; (16) is a control valve drive output value calculation means; (14) and control valve drive output correction value calculation means (15)
) is a control valve drive output means that controls the valve opening degree of the flow control valve (5) by passing a current through the electromagnetic coil (5a) such that the drive output value calculated by

FIG. 2 is a circuit diagram showing the detailed configuration of the main parts of the embodiment shown in FIG. (34
), (35) is an A1-port converter that converts the temperature detection value input as an analog quantity into a digital quantity and applies it to the input circuit (33), (3rd) is the output of the output circuit (34) (37) is an operation switch for the heat pump device; (38) is a changeover switch for switching the heat pump device between cooling operation and heating operation; II), (42), and (a3) are temperature detection devices (
Resistors connected to the power supply in series with 11), (12) and (13), respectively, (44) and (45) are operation switches (3?),! The resistors (46) are connected to the power supply in series with the il] conversion switches (38), respectively, and are the main body of the control device.

Since the operation of the refrigeration cycle of the heat pump device configured as described above is the same as that of the conventional device, its explanation will be omitted.
The flowchart will be explained below with reference to the flowchart in the figure. Flowchart 1 in FIG. 3 shows the part of the program stored in the memory (32) of the microcomputer (30) shown in FIG. 2 that controls the lAt1-control valve (5). be.

First, when the operation switch (37) is turned on, a signal indicating the state of the changeover switch (38) is input to the input circuit (33) and the compressor (1) starts operating. The program is executed from step (50) in the figure. In step (50), time is counted from the start of operation, and 30
The process proceeds to step (51) every second, but otherwise the process proceeds to step (54). this house,
In step (51), temperature detection devices (11) and (12)
The user-side fluid temperature Ga and the non-user-side fluid temperature Ta obtained respectively are read. And step (52)
, In (53), the control drive output standard 4 of the flow control valve (5) is determined based on the read fluid temperature converters W and Ta, respectively.
(t Q i s and compressor discharge refrigerant reference temperature Tds
Calculate. On the other hand, in step (54), it is determined whether or not the defrosting operation is in progress. If the defrosting operation is in progress, the process proceeds to step (64), and if the defrosting operation is not in progress, the process proceeds to step (55).
Proceed to processing.

Next, in step (55), it is determined whether the fluid temperature Ta on the user side and the fluid temperature Ta on the non-user side are within a preset range, or whether the discharge refrigerant temperature should be corrected to exceed the set range. If so, the process advances to step (56). In step (5B), time is counted from the start of operation, and it is determined whether or not it is every four minutes, and the process of step (57) is performed every four minutes. In this step (57), the compressor discharge refrigerant device Td detected by the temperature detection device (13) is read, and in step (58), this compressor discharge refrigerant temperature Td and the compressor discharge refrigerant temperature Td calculated in the above step (53) are read. (Compared with the mold temperature T, 1. When T++>T++, +A, that is, the actual temperature Td is higher than A'C compared to the reference temperature TIIZ.
1- If the value is higher, the process proceeds to step (59) and the control valve drive output correction 4riQic of the flow rate control block 1 (5) is set to C.
It only decreases. Here, if the relationship Td< rd5+A is satisfied, the process proceeds to step (60), and it is determined whether or not the compressor discharge cold storage standard temperature Tds is lower by B°C, that is, if T,<'r, -B. Proceed to step (61), increase the control block ``drive output supplement +I fi Q r c'' by C, and proceed to step (62).
Compressor discharge refrigerant temperature Td is (Tds-n) and (T++, ,
+A), the process of step (60) is not executed, so the control block "Drive output correction &t Q
: c does not change. Then, in step (62), Qi
r is memorized, and in step (B3) step (52)
The control valve 1 drive output reference value Qis obtained in step 111 and the control valve drive output correction (If'
! After controlling Q i c and determining the control valve drive output value Q1, this control valve drive output value Q1 is determined in step (66).
However, in addition to the output circuit (34) shown in FIG. 2, a pulse generator (36) controls the current flowing through the electromagnetic coil (5a) of the flow j-1 control 311 valve (5). In addition, step (5
5), the user side fluid temperature TW and the non-use side fluid temperature T,
If it is outside the preset range, the process proceeds to step (62), so the control valve drive output value 1F value Qic due to the compressor discharge refrigerant temperature Td does not change. This means that under the condition that the fluid temperature TW on the user side is not so high during normal heating and rotation, the high pressure is low and the compressor discharge cold temperature Td does not become high, so there is no need to add the control valve drive correction value Qic. It means.

- On the other hand, if it is determined in step (58) that defrosting operation is in progress, proceed to step (64), reset the timer count, and set control valve drive output value Qin to a constant value in step (65). . During defrosting operation, the user fluid temperature TI1
．． For example, the flow X1 is independent of the unused fluid temperature Ta.
The defrosting time is shortened by setting the valve opening degree of the 1 control valve (5) to be maximum. Also, during defrosting operation, step (5)
Since the processes 5) to (63) are not executed, the unstable compressor discharge refrigerant temperature Td during defrosting is read and the control valve drive output correction value Qic is not rewritten. Furthermore, for 4 minutes after the end of defrosting, the judgment in step (56) does not proceed to the process in step (57), and during unstable operation after the end of defrosting, the control valve drive output correction value Qic is 1" : m
Avoiding problems.

By the way, step (50) I! I would like to prevent the erroneous call to 111 in the unstable operation range after the defrosting is completed as described in 1-1.
This not only prevents correction in the unstable operation range immediately after the start of operation. In addition, control valve drive output reference value Qi
s is rewritten every 30 seconds, whereas the control valve drive output correction value Qic based on the compressor discharge cold temperature Td is rewritten to 4 minutes iσ because of the flow! This is to prevent unnecessary opening/closing operations of the control valve (5). That is, the flow z11. Since the compressor discharge refrigerant temperature Td changes with a considerable time delay in response to a change in the control valve (5), the correction interval is lengthened in consideration of this delay time.
This avoids frequent correction operations and at the same time allows the operating state to be reached in a short time.

Note that the calculation cycle of the control valve drive cap (half-value Qis) and the calculation cycle of the control valve drive output correction value Qic are not limited to the above-mentioned 30 seconds and 4 minutes, but may vary depending on the heating and cooling loads. Although it may be determined appropriately, by setting the latter cycle much larger than the former, it is possible to prevent the flow rate control valve from opening and closing unnecessarily frequently.

[Effect of the invention] As is clear from the above explanation, according to the present invention,
Since the first calculation means calculates the control valve drive output reference value based on the detected usage-side fluid temperature and non-use-side fluid temperature, the control valve drive output reference value is calculated based on the detected usage-side fluid temperature and non-use-side fluid temperature. The compressor can be made to respond appropriately, and the operating condition of the compressor can always be maintained in good condition.

In addition, a second
Since the calculation means compensates for the control valve driving output reference value, abnormal overheating of the compressor discharge refrigerant temperature can be prevented. Furthermore, even if liquid back operation is performed for some reason,
Since it is possible to detect an abnormal drop in the discharge refrigerant temperature and return to normal operation, the reliability of the heat pump can be improved.

Furthermore, only when the temperature of the user side fluid and the non-use side wave body exceeds a predetermined range, the control valve drive output group 4-1
Since the value is corrected, frequent opening and closing operations of the flow control valve 111 can be suppressed to improve reliability and extend life.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram of an embodiment of the present invention, FIG. 2 is a circuit diagram showing the detailed configuration of the main part of the embodiment, and FIG. 3 is a flowchart for explaining the operation of the embodiment. FIG. 4 is an overall configuration diagram of a conventional heat pump device. In the figure, (1) is the compressor, (2) is the switching valve, (3)
is a heat exchanger on the use side, (4) is a heat exchanger on the non-use side, and (5) is an electric flow Jii control valve. (5a) is an electromagnetic coil, (8) is an accumulator, (11) is a user-side body temperature detection device, (12) is a non-use-side fluid temperature detection device, and (13) is a discharge refrigerant temperature detection device. In each figure, the same reference numerals indicate the same or corresponding parts. Agent Masu Oiwa Yuka 4 Figures 1939, Month, Day 2, Name of invention Heat pump device 3, Representative Moriya Shiki 4, Agent 5, Subject of amendment 6, Contents of amendment (1) Details The description "overheating" on page 2, line 18 of the book was changed to "
"Heating" and Supplement 1)-. (2) I! "Heat exchanger (
The description “Hereinafter referred to as heat exchanger; (3) Specification, 1: Page 15, line 6, ``In the relationship,
'' should be amended to read ``if there is a relationship between.'' (4) "Step (59) J" on page 16, line 10 of the specification
The description "Step (59)" will be corrected. (5) On page 17, line 17 of the specification, the statement 1 that says "becomes in an operating state in a short period of time" is supplemented with "in a stable continuous state F) in a short period of time." -1-

Claims (1)

[Claims] A path that connects a first heat exchanger that forms a refrigeration cycle with the compressor and exchanges heat between the refrigerant and the fluid on the user side, and a second heat exchanger that exchanges heat between the refrigerant and the fluid on the non-user side, In a heat pump device equipped with a flow rate control valve that controls the flow rate of liquid refrigerant, a first temperature detection device that detects the temperature of the refrigerant discharged from the compressor, and a second temperature detection device that detects the temperature of the usage-side fluid. and a third temperature detection device for detecting the temperature of the unused fluid, and the second and third temperature detection devices.
a first calculation means for calculating a control valve drive output reference value for setting the flow control valve to a reference opening degree based on the temperature detected by the temperature detection device; and detection by the second and third temperature detection devices. It is determined whether each temperature exceeds a predetermined range, and when the temperature exceeds the predetermined range, a control valve drive output correction value is calculated based on the temperature detected by the first temperature detection device, and the control valve is driven. a second calculation means for correcting an output reference value, and controlling the opening degree of the flow rate control valve based on the corrected control valve drive output reference value.