JP2016095109A - High speed cutoff electronic linear expansion valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a high speed cutoff electronic linear expansion valve for eliminating occurrence of energy loss in reference to the prior art defects that the energy loss is generated during an intermittent operation of a refrigeration cycle and as one cause for it, when the compressor is stopped, high pressure liquid refrigerant and low pressure refrigerant are mixed to each other and so the mixed substance must be separated into the high pressure refrigerant and the low pressure refrigerant when the compressor is started to operate.SOLUTION: A high speed cutoff type linear expansion valve 1 is constituted by two stage closing elements, i.e. a rotary needle valve 8 by a gear type electric valve mechanical element, low input position setting operating unit input means and a high speed cutoff valve 14 of electromagnetic driving element, and also has means for controlling a low input, liquid sealing prevention and a fast warming characteristic.SELECTED DRAWING: Figure 1

Description

The present invention relates to an electronic expansion valve for refrigerant control of a vapor compression refrigeration cycle.

Conventional electronic control valves for refrigerant control include a gear system such as an electric valve and a direct drive system such as an electromagnetic valve. For example, in the expansion valve described in Patent Document 1 and Patent Document 2, the motorized valve gear system energizes the coil to rotate the rotor, male screw, and needle, and the opening end area of the upper part of the valve seat is variable by the vertical movement of the needle. Thus, the flow rate is controlled by varying the refrigerant passage opening area. On the other hand, in an expansion valve that employs a direct drive system such as a solenoid valve, in the expansion valve described in Patent Document 3, the refrigerant circulation amount is controlled by changing the time ratio duty ratio for energizing the coil section. .

JP 2009-264530 A JP 2013-160331 A Patent application notice 3-40309 JP 2012-42081 A

Dynamic characteristics and control of refrigeration cycle, Japan Society of Refrigeration and Air Conditioning, 2009, pp34 Revision 3 Automatic refrigeration equipment, Refrigeration and Air Conditioning Society of Japan, 2013, pp34

In conventional refrigeration cycle equipment such as air conditioners and refrigerators, not only fixed frequency operation machines but also inverter compressor-equipped machines are accompanied by ON / OFF switching of the refrigeration cycle during partial load operation. There was a problem that energy loss occurred due to intermittent operation of ON / OFF, and operating efficiency (APF) deteriorated. The cause of energy loss during this ON / OFF intermittent operation is that the high-pressure liquid refrigerant passes through the expansion valve and mixes with the low-pressure / low-temperature two-phase refrigerant at the time of OFF to increase the entropy to an average uniform refrigerant. When the restart is turned on, this uniform refrigerant must be separated again into a high-pressure liquid refrigerant and a low-pressure low-temperature two-phase refrigerant. This separation work is an energy loss.

The present invention has been made in view of the above-mentioned problems of the prior art, and at the same time that the compressor is turned off (stopped), the expansion valve is shut off at high speed and the high pressure liquid refrigerant is present in the low pressure two-phase refrigerant. It is prevented from flowing into the evaporator. It is another object of the present invention to provide an inexpensive and reliable high-speed shut-off type electronic linear expansion valve that has a small expansion valve drive input and is excellent in energy saving.

In the gear type motor operated valve described in Patent Document 1, it takes several tens of seconds to rotate the screw part from the state in which the refrigerant flow rate is controlled to the fully closed state of the motorized valve at the same time as the compressor is stopped to fully close the valve seat. The high-pressure liquid refrigerant flows out to the low-pressure evaporator. Even with the fully closed system described in Patent Document 2, it is also based on a gear-type motorized valve, and even if it can prevent the needle from biting into the valve seat, it cannot be shut off at high speed. Take it.

On the other hand, the electromagnetically driven expansion valve shown in Patent Document 3 can shut off the high pressure and the low pressure at high speed, but current must always flow through the electromagnetic coil during normal refrigerant control. As long as the gear type motor operated valve is positioned, the electric input is different from zero. From the viewpoint of energy saving, the electromagnetic drive type is inferior to the gear type drive type.

Therefore, Patent Document 4 discloses an electromagnetic valve-integrated expansion valve. This is an expansion valve for turning on and off the rear side cooling in the front side cooling and rear side cooling of the car, and combined with a temperature type automatic expansion valve that detects the degree of superheat of the outlet refrigerant of the evaporator The solenoid valve is open when the solenoid valve is energized and closed when the solenoid valve is not energized. That is, while using the rear side cooling, it is necessary to energize the solenoid valve, which is not energy saving. Furthermore, it can be applied only to refrigerant flow control based on the degree of superheat of the evaporator, assuming operation with one or two cooling units. Heating capacity refrigerant flow control based on the degree of supercooling of high-pressure liquid refrigerant for heating is not considered. Has the disadvantages. In particular, the refrigerant circuit is closed during heating operation in winter, and there is a risk of liquid ring explosion.

In order to make the high-speed shut-off type electronic linear expansion valve for the above purpose low energy input, energy saving, inexpensive, reliable, and versatile applicable to both cooling and heat pump heating, the expansion valve of the present invention Has a positioning function for gear type electric valve machine elements and is divided into high-speed shut-off electromagnetic drive elements. The gear type electric valve machine elements are composed of a rotor magnet, male screw part, female screw part and rotary needle valve. The high-speed cutoff electromagnetic drive element is composed of a plunger, a spring, a fixed iron core, a high-speed cutoff needle, and a high-speed cutoff valve. Common elements are a first refrigerant flow path, a second refrigerant flow path, a coil, A double valve seat is provided.

Furthermore, in the high-speed cutoff electronic linear expansion valve of the present invention, the high-speed cutoff needle passes through the rotary needle valve of the gear-type electric drive element independently and easily slips. The rotary needle valve rotates integrally with a rotor magnet and a male screw part, and the electromagnetic drive part is characterized in that a plunger, a high-speed cutoff needle, and a high-speed cutoff valve move integrally up and down. Furthermore, the high-speed cutoff electronic linear expansion valve of the present invention is characterized in that the rotary needle valve adjusts the opening of the top valve seat of the double valve seat and the high-speed cutoff valve opens and closes the bottom valve seat. Furthermore, the high-speed interrupting type electronic linear expansion valve of the present invention has a mode of exciting a coil by generating a rotating magnetic field and a gear-type electric drive mode, and magnetizing a fixed iron core with a fixed magnetic field without rotating the magnetic field. It has a mode for closing the shut-off valve.

In the high-speed cutoff electronic linear expansion valve of the present invention, the gear type electric expansion valve is in charge of refrigerant flow rate control during refrigeration cycle operation, and the electric input is necessary only for positioning of the rotary needle valve and rotates slowly. Less torque and energy saving. The refrigerant flow control signal may be the degree of superheat of the refrigerant at the outlet of the evaporator for cooling, the degree of supercooling of the refrigerant at the outlet of the condenser during heating, the temperature of the refrigerant at the outlet of the compressor, or the degree of superheat of the discharged refrigerant. good. Furthermore, at the same time that the compressor is stopped when the thermo is turned OFF / ON during partial load operation, the high-speed shut-off valve can be instantly fully closed by the suction force generated by the magnetization of the fixed iron core by changing the magnetic field of the coil from a rotating magnetic field to a fixed magnetic field. By shutting off the supercooled liquid refrigerant, it can be prevented from flowing into the low-pressure evaporator, and ON / OFF loss can be eliminated.

It is explanatory drawing which showed the flow control state of the high-speed interruption | blocking type | mold electronic linear expansion valve of this invention. It is explanatory drawing which showed the 1st stage (high-speed cutoff valve) fully closed state of the high-speed cutoff electronic linear expansion valve of this invention. It is explanatory drawing which showed the 1st stage (rotary motor operated valve) fully closed state of the high-speed interruption | blocking type | mold electronic linear expansion valve of this invention. It is explanatory drawing which shows the two-stage fully closed state of the high-speed interruption | blocking type | mold electronic linear expansion valve of this invention. It is explanatory drawing which shows the general refrigerant circuit figure containing the high-speed interruption | blocking type | mold electronic linear expansion valve of this invention. 6 is an explanatory diagram showing a time series distribution of a refrigerant described in Document 5. FIG. It is explanatory drawing of a refrigerant circuit when the high-speed interruption | blocking type | mold electronic linear expansion valve of this invention is integrated in a heat pump. 10 is an explanatory diagram of a rotating magnetic field applied to a coil described in Document 6. FIG. It is explanatory drawing which shows the operation mode list | wrist of the high-speed interruption | blocking type | mold electronic linear expansion valve of this invention. Another embodiment of the double valve seat and coil of the high-speed cutoff electronic linear expansion valve of the present invention

Hereinafter, the best mode for carrying out the present invention will be described.

FIG. 1 is a cross-sectional view of the high-speed cutoff electronic linear expansion valve of the present invention in a flow rate control state. FIG. 2 is a cross-sectional view of the high-speed cutoff electronic linear expansion valve of the present invention in a one-stage (high-speed cutoff valve) fully closed state. FIG. 3 is a cross-sectional view of the high-speed cutoff electronic linear expansion valve according to the present invention in a single-stage (rotary electric valve) fully closed state. FIG. 4 is a cross-sectional view of the high-speed cutoff electronic linear expansion valve of the present invention in a two-stage fully closed state. The high-speed cutoff electronic linear expansion valve of the present invention includes a first refrigerant flow path 2, a second refrigerant flow path 3, a coil 4, a rotor magnet 5, a male thread part 6, a female thread part 7, a rotary needle valve 8, It has a double valve seat 9, a fixed iron core 10, a spring 11, a plunger 12, a high-speed cutoff needle 13, a high-speed cutoff valve 14, and a seat 15.

The high-speed shut-off type electronic linear expansion valve is composed of a mechanical part for driving a gear-type motor-operated valve and a mechanical part shared with a mechanical part for a high-speed electromagnetic drive direct acting system.

In the gear type electric valve drive system, the rotor magnet 5 rotates in response to the rotating magnetic field generated in the coil 4, and the male screw portion 6 coupled thereto rotates. On the other hand, the female screw portion 7 is fixed to the high-speed cutoff electronic linear expansion valve 1, and the male screw portion 6 moves up and down along the screw thread while rotating. The rotary needle valve 8 at the front end of the male screw portion 6 moves up and down while rotating, and the opening area of the upper opening end of the double valve seat 9 is changed to control the flow rate of the passing refrigerant.

On the other hand, in the high-speed electromagnetic drive system, the plunger 12 overcomes the force of the spring 11 by the magnetic force of the fixed iron core (cue) 10 by applying a fixed magnetic field of high electrical input that does not rotate to the coil 4 and attracts it. The high-speed shut-off needle 13 fixed to the plunger 12 passes through the coaxial center of the fixed iron core 10 and the rotary needle valve 8, and the leading high-speed shut-off valve 14 is pressed against the seat 15 so that the double valve seat Fully close the lower open end of 9.

FIG. 5 shows a general refrigerant circuit diagram. The refrigerant compressed into the high-temperature and high-pressure gas by the compressor 20 flows in the → direction, condenses into a high-pressure liquid by the condenser 20, and reaches a high-speed cutoff electronic linear expansion valve. The expansion valve reduces the pressure to a low-pressure two-phase refrigerant, evaporates and gasifies in the evaporator 40, and further forms a circulation cycle to the compressor 20. In particular, FIG. 6 shows the refrigerant distribution from the start of the compressor described in Document 5 to the stable operation after the start. The features are listed. 1. Before starting up, 80% of the total refrigerant charge lies in the evaporator. (T = 0 seconds) 2. 40 seconds after startup (0.667 minutes later), nearly 40% of the refrigerant is dissolved and accumulated in the compressor. After 3.7 minutes and 50 seconds (7.833 minutes), about 60% of the refrigerant is distributed to the condenser. 4. When stable (after 20 minutes), 55% is distributed in the condenser, 15% in the evaporator, and 10% in the compressor. In other words, when the compressor is thermo-off (stopped), the high-pressure, low-temperature, low-entropy liquid refrigerant that was 55% in the condenser passes through the expansion valve, flows into the low-pressure, low-temperature evaporator, and becomes an average high-entropy refrigerant. Become. This must be separated again into a high-pressure liquid refrigerant and a low-pressure refrigerant when the compressor is started. Here, compressor start / stop energy loss occurs. Therefore, it is necessary to shut off the high-pressure condenser and the low-pressure evaporator instantly (within 1 second) at the same time as the compressor is stopped with a high-speed shut-off type electronic linear expansion valve.

Next, the overall operation and operation mode of the high-speed cutoff electronic linear expansion valve 1 will be described. The high-speed cutoff electronic linear expansion valve in FIG. 1 shows a state during flow rate control in the refrigerant circuit diagram shown in FIG. The double valve seat 9 has both the rotary needle valve 8 and the high-speed shut-off valve 14 open. In particular, the rotary needle valve 8 has an appropriate opening degree (opening area) during flow control, and the high-speed shut-off valve 14 is fully open. It has become. A rotating magnetic field is generated in the coil 4 so that the rotor magnet 5 and the male screw portion thereof are rotated, and the rotary needle valve 8 is controlled to an appropriate valve opening while moving up and down. This gear type electric valve drive system is small in electric input and energy saving because the position of the rotary needle valve is fixed even when the energization is not performed when the driving torque is small and positioning is completed. On the other hand, during this mode, the electromagnetic driving force is insufficient due to the small electrical input, the electromagnetic force of the fixed iron core (cue-in) 10 is weak, and the plunger 12 (integrated with the high-speed cutoff valve and high-speed cutoff needle) Therefore, it is pressed in the opening direction (upward).

Next, the one-stage (high-speed shut-off valve) fully closed state will be described with reference to FIG. First, the refrigeration cycle is changed from the flow control state shown in FIG. 1, which is a normal operation state, from the rotating magnetic field of the coil 5 to the fixed magnetic field at the same time as the compressor is stopped, and the electric input to the coil is increased. Along with this, the rotor magnet stops, and all the gear type electric drive units stop moving accordingly. On the other hand, the fixed iron core of the electromagnetic mechanism drive unit is magnetized and the plunger is attracted downward by the cue force, so that the lower opening end of the double valve seat is fully closed. In this case, the fixed magnetic field is energized when the high-speed shut-off valve is fully closed. In order to reduce this electric input, the rotating magnetic field is further energized, the gear type electric drive system is used, and the gear type electric drive system is also fully closed, resulting in the two-stage fully closed state of FIG. After that, if the current to the coil is set to 0, the input 0 to the coil can be realized by positioning in the one-stage (rotary electric valve) fully closed state in FIG. The generation of the rotating magnetic field is shown in FIG.

Next, a second embodiment shown in FIG. 7 will be described. The same numbers indicate the same names. FIG. 7 represents the cooling and heating circuit. It is the schematic of a general heat pump air conditioner. In the figure, reference numeral 50 denotes a four-way switching valve, and the indoor heat exchanger 41 and the outdoor heat exchanger 31 constitute a cycle. Solid arrows indicate the refrigerant flow during the heating operation, and broken arrows indicate the refrigerant flow during the cooling operation and the refrigerant flow during the reverse defrost operation. Here, the first refrigerant channel 2 and the second refrigerant channel 3 of the high-speed cutoff electronic linear expansion valve are reversed. FIG. 9 shows the operation control mode of the high-speed cutoff electronic linear expansion valve and the operation procedure according to the control purpose. 1. When the thermostat is turned off during cooling operation, that is, the compressor is stopped and the indoor blower is in operation: The purpose of the control of this expansion valve is to fully close the expansion valve to prevent mixing loss of refrigerant at high pressure and low pressure Yes 1.2 is to keep the low-pressure refrigerant temperature low to prevent re-evaporation of the dehumidified water accumulated on the surface of the indoor heat exchanger (evaporator). For this purpose, the expansion valve needs to be fully closed by one stage (high-speed shutoff valve). Furthermore, the opening degree on the rotary electric valve side is kept waiting for the opening degree on the rotary electric valve side toward the next thermo-on state of the thermo-off state. 2. When the power supply during cooling operation is turned off, that is, when the compressor is turned off and the indoor blower is also turned off: In this case, when the air conditioner is not used, 2.1 standby power is set to 0 and 2.2 liquid seal prevention (contains liquid refrigerant in a small space) Open high and low pressures to avoid explosion if exposed to high temperatures. At this time, the expansion valve is left open with the high-speed shut-off valve fully open, the electric input is 0, and the rotary electric valve is also left open with the opening during operation. 3. When the thermostat is OFF during heating operation (compressor OFF and indoor fan also OFF): The control objectives are 3.1 high-low pressure refrigerant mixing loss prevention and 3.2 high-speed heating startup. At this time, the operation of the expansion valve is fully closed and further turned ON, and the rotary electric valve opening degree of the preparation is set to be twice the opening degree during stable operation. 4. The control purpose when the power is turned off during heating operation is 4.1 standby power reduction and 4.2 no high temperature, so there is no worry of liquid sealing, but it is necessary to prevent liquid refrigerant from stagnating in the compressor due to low outside air temperature . The expansion valve is operated with one-stage (high-speed shut-off valve) fully closed → two-stage fully closed → first-stage (rotary motor-operated valve) fully closed and electrical input set to zero.

Further, another configuration example showing the same effect will be described. Although the coil of the high-speed shut-off type electronic linear expansion valve is shown integrally, the gear-type rotary electric valve driving coil and the electromagnetic high-speed driving coil may be configured separately. Further, the double valve seat does not have this configuration, and the high speed shut-off valve and the seat may be installed in the second refrigerant flow path as shown in FIG.

The present invention is used in an air conditioner such as a room air conditioner, a packaged air conditioner, a car air conditioner, a multi air conditioner for buildings, and a refrigeration cycle such as a refrigerator, a freezer / refrigerator showcase, etc. It can be applied. In addition, standby power can be reduced and refrigerant distribution can be controlled.

1 High-speed cutoff electronic linear expansion valve
2 First refrigerant flow path
3 Second refrigerant flow path
4 coils
5 Rotor magnet
6 Male thread
7 Female thread
8 Rotary needle valve
9 Double valve seat
10 Fixed iron core
11 Spring
12 Plunger
13 Fast shut-off needle
14 High speed shut-off valve
15 seats
20 Compressor
30 condenser
31 Outdoor heat exchanger
40 Evaporator
41 Indoor heat exchanger
50 Four-way switching valve

Claims (6)

The expansion valve for the refrigeration cycle is an electronic expansion valve that has a double-closing function of gear-type electric drive system and electromagnetic direct drive full-close system, and can shut off between high pressure and low pressure at high speed within 0.1 seconds. . In the expansion valve, in the flow control state mode, the high-speed shut-off valve is not energized and is kept open, the electric rotary needle valve is kept at an appropriate opening degree, and the one-stage (high-speed shut-off valve) fully closed state mode is in the fixed magnetization energized state. The high-speed shut-off valve of the two-stage valve seat is in a fully closed state, the electric rotary needle valve is in a non-energized fixed opening state after positioning is determined, and the one-stage (electric rotary needle valve) fully closed state mode is on the electric rotary needle valve side It is characterized in that it is not energized in the fully closed positioning state, the high-speed shut-off valve side coil is not energized to open the valve, and in the double fully closed mode, both valves are closed. In the expansion valve according to the above items 1 and 2, the coil is a coil formed by simultaneously or separately configuring a rotating electric field type rotary magnet driving part of low electric input and a coil of high electric input plunger direct drive by a fixed magnetic field coil. It is characterized by its control. In the expansion valve according to any one of the above-described items 1, 2, and 3, a high-speed shut-off needle is penetrated through the center portion of the rotary needle valve at a coaxial center portion. In relation to 1, 2, 3, and 4 of the expansion valve described above, when the operation mode is the cooling thermo-off, the control purpose is to prevent high / low pressure refrigerant mixing and to prevent re-evaporation of dehumidified water on the surface of the evaporation heat exchanger. The procedure is one-stage (high-speed shut-off valve) fully closed and the rotary electric valve for starting the next compressor is set to input 0 for maintaining the opening during operation, and the control purpose is set to standby power 0 in the cooling power OFF mode. To prevent liquid sealing, the input is 0 with the high speed shut-off valve fully open, and the rotary electric valve is set to 0 with the opening maintained during operation. According to claims 1, 2, 3, 4 and 5 of the above expansion valve, when the operation mode is thermo-off during heating, the control purpose is to prevent high-low pressure refrigerant mixing loss and to start up high-speed heating. The rotary motor-operated valve is opened at twice the opening just before the stop for closing and compression activation. Input 0 after positioning is determined. When power is turned off when the operation mode is heating, the control purpose is to reduce standby power and prevent liquid refrigerant from being trapped in the compressor under low outside air temperature, so one-stage (high-speed shutoff valve) fully closed → two-stage fully closed → one-stage (Rotary motor-operated valve) Fully closed and both valves are set to input 0. It is characterized by that.