JP2005274102A - Selector valve opening/closing method and refrigerant flow control valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a compact refrigerant flow control valve capable of reducing pressure loss of refrigerant. <P>SOLUTION: A selector valve 13 is arranged inside a valvae chamber 1a of a valve main body 1 freely to slide upward and downward. The selector valve 13 is seated/separated on/from a main valve seat 16 by a pressure difference between the pressure of a space P formed over the selector valve 13 and the pressure of a first port 11 or a second port 12. A variable throttle part is structured of a variable throttle hole 28 and a needle 26a of a needle valve 26. A stepping motor 70 is structured of a coil 25, a rotor 23 and a shaft 24. The stepping motor 70 is driven to control the variable throttle part and to control the pressure difference. The stepping motor 70 is formed compact. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  TECHNICAL FIELD The present invention relates to a refrigerant flow control valve that switches between a valve open state and a throttle state for refrigerant expansion, and more particularly to a switching valve opening / closing method and a refrigerant flow rate suitable for a dry control valve for dry operation in an air conditioner. It relates to a control valve.

2. Description of the Related Art Conventionally, there is a dry control valve that squeezes refrigerant by interposing it between indoor heat exchangers that are divided into two parts in order to perform dry operation (dehumidification mode) with an air conditioner. This dry control valve is in a throttled state for controlling the refrigerant (controlling the flow of the refrigerant) during dry operation, and in order to make the indoor heat exchanger divided into two during normal cooling / heating operation function as one indoor heat exchanger. Thus, the valve is opened without restricting the flow of the refrigerant. Then, as disclosed in Japanese Patent Laid-Open No. 2001-310540 (dehumidifying throttle valve) and Japanese Patent Laid-Open No. 2003-90650 (flow rate control device), a switching valve that switches between the throttled state and the valve-opened state is driven. For example, an electromagnetic solenoid or a stepping motor is used.
JP 2001-310540 A JP 2003-90650 A

  However, in the dehumidifying throttle valve disclosed in Japanese Patent Laid-Open No. 2001-310540 and the flow rate control device disclosed in Japanese Patent Laid-Open No. 2003-90650, the switching valve is directly driven by the stepping motor driving force of the electromagnetic solenoid. If the force is weakened, it is difficult to increase the switching valve, and the valve seat diameter cannot be increased. For this reason, there is a problem that the pressure loss due to the dynamic pressure loss and turbulence loss of the refrigerant increases. Further, there is a problem that the electromagnetic solenoid and the stepping motor that increase the driving force are increased, and the entire dry control valve (refrigerant flow control valve) is increased in size.

  This invention makes it a subject to provide the small refrigerant | coolant flow control valve which reduces the pressure loss of a refrigerant | coolant.

  The switching valve opening and closing method according to claim 1 is a method for switching and controlling a valve opening state in which the switching valve is driven to equalize the pressure between the two ports and the refrigerant is allowed to pass through, and a throttle state for expanding the refrigerant. The switching valve is opened and closed by controlling the pressure in the pressure control space using a variable throttle valve that controls the refrigerant flow rate.

  According to the switching valve opening / closing method of claim 1, since the variable throttle valve used in the method may have a small opening / closing area, the differential pressure resistance applied to the variable throttle valve is small, and the motor for driving the variable throttle valve Can be small. Further, since the switching valve is driven by a pilot valve using a variable throttle valve, it is not necessary to increase the driving force even if the valve seat diameter is increased. Therefore, a refrigerant flow control valve having a reduced pressure loss of the refrigerant can be obtained.

  The refrigerant flow rate control valve according to claim 2 is a refrigerant flow rate control for switching and controlling a valve open state in which the switching valve is driven to equalize the pressure between the two ports and allow the refrigerant to pass therethrough and a throttle state for expanding the refrigerant. A valve chamber in which a first port and a second port are formed; a valve chamber disposed in the valve chamber and seated on a valve seat formed on the second port side; A switching valve which shields the first port and is spaced from the valve seat and conducts the second port and the first port; and is formed in the switching valve, and is formed on the opposite side of the valve seat by the switching valve. A fixed restrictor for restricting the flow of the refrigerant between the pressure control space and the first port; and a constriction that is arranged to be able to conduct to the pressure control space and communicated with the second port by a conduit; A variable throttle portion that variably throttles the flow of refrigerant between the pressure control space and the conduit by means of a valve; A motor that controls the throttle amount of the variable throttle unit by driving a throttle valve, and controls the pressure of the pressure control space by the throttle amount of the variable throttle unit, and the pressure control space and the first port The seating / separation of the switching valve is switched by controlling the differential pressure and the differential pressure between the pressure control space and the second port.

  According to the refrigerant flow control valve of the second aspect, the pressure acting above and below the variable throttle portion may be a small differential pressure necessary for the operation of the switching valve, and the opening area of the variable throttle portion may be small. Since the differential pressure resistance applied to the valve is small, the motor for driving the throttle valve may be small. Further, since the switching valve is driven by the pilot by the variable restrictor, it is not necessary to increase the driving force even if the valve seat diameter is increased. Therefore, a refrigerant flow control valve having a reduced pressure loss of the refrigerant can be obtained.

  According to a third aspect of the present invention, there is provided a refrigerant flow rate control valve having the configuration according to the second aspect, wherein a silent filter is provided on the pressure control space side and the conduit side of the throttle portion.

  According to the refrigerant flow control valve of the third aspect, the same effect as that of the second aspect can be obtained, and the noise passing through the throttle portion can be reduced by the silent filter.

  According to a fourth aspect of the present invention, there is provided a refrigerant flow control valve having the configuration of the second or third aspect, wherein the conduit is formed in a main body case constituting the valve chamber.

  According to the refrigerant flow control valve of the fourth aspect, the same effect as that of the second or third aspect can be obtained, and the conduit that communicates the variable throttle portion and the second port is not outside the case, so that the size can be reduced. it can.

  A refrigerant flow control valve according to a fifth aspect includes the configuration according to the second, third, or fourth aspect, and includes two joint pipes that communicate with the first port and two joint pipes that communicate with the second port. It is characterized by that.

  According to the refrigerant flow control valve of the fifth aspect, the same effect as that of the second, third or fourth aspect can be obtained, the pressure loss can be reduced in the indoor heat exchanger, and the space and cost of the indoor unit can be reduced. Can be planned.

  According to the switching valve opening and closing method of the first aspect, it is possible to obtain a small refrigerant flow control valve with reduced refrigerant pressure loss.

  According to the refrigerant flow control valve of the second aspect, the same effect as that of the first aspect can be obtained.

  According to the refrigerant flow control valve of the third aspect, the same effect as in the second aspect can be obtained, and the refrigerant passing sound of the throttle portion can be reduced.

  According to the refrigerant flow control valve of the fourth aspect, the same effect as that of the second or third aspect can be obtained, and the refrigerant flow control valve can be downsized.

  According to the refrigerant flow control valve of the fifth aspect, the same effect as that of the second, third, or fourth aspect can be obtained, the pressure loss can be reduced in the indoor heat exchanger, and the space and cost of the indoor unit can be reduced. be able to.

  Next, an embodiment of the refrigerant flow control valve of the present invention will be described with reference to the drawings. FIG. 1 is a view showing a structure of a refrigerant flow control valve according to an embodiment and a main part of an air conditioner to which the refrigerant flow control valve is applied. FIG. 1 shows a state during a dehumidifying operation. 2A is a cross-sectional view taken along the line AA in FIG. 1 (bottom view), and FIG. 2B is a cross-sectional view taken along the line CC in FIG. FIG. 1 shows a cross section taken along line BB in FIGS. 2 (A) and 2 (B).

  In the figure, 10 is a dry control valve as a refrigerant flow rate control valve of the embodiment, 20 is an indoor heat exchanger mounted on the indoor unit, 30 is an expansion device, 40 is an outdoor heat exchanger mounted on the outdoor unit, and 50 is For example, a rotary flow path switching valve constituting the four-way valve, 60 is a compressor. The indoor heat exchanger 20 includes a first heat exchanger 20A connected to the expansion device 30 side and a second heat exchanger 20B connected to the flow path switching valve 50 side, and the dry control valve 10 is the first heat exchanger 20B. It is connected between the heat exchanger 20A and the second heat exchanger 20B. Then, the dry control valve 10, the first heat exchanger 20A, the second heat exchanger 20B, the expansion device 30, the outdoor heat exchanger 40, the flow path switching valve 50, and the compressor 60 are respectively connected by conduits as illustrated. It is connected and constitutes a heat pump refrigeration cycle 100.

  The flow path of the refrigeration cycle 100 is switched to two flow paths of “cooling mode” and “heating mode” by the flow path switching valve 50. In the cooling mode, as indicated by solid line arrows in FIG. 1, the refrigerant compressed by the compressor 60 flows into the outdoor heat exchanger 40 from the flow path switching valve 50, and passes through the expansion device 30 and the first heat exchanger 20A. Through the dry control valve 10, the refrigerant liquid that has flowed out flows into the second heat exchanger 20B, and flows from the second heat exchanger 20B into the compressor 60 through the flow path switching valve 50. In the heating mode, as indicated by the dashed arrows in FIG. 1, the refrigerant compressed by the compressor 60 flows into the second heat exchanger 20B from the flow path switching valve 50, and the dry control valve 10 and the first heat exchanger. 20A, the expansion device 30, the outdoor heat exchanger 40, the flow path switching valve 50, and the compressor 60 are circulated in this order.

  The dry control valve 10 is opened during the operation mode other than the dehumidifying operation, and the function of the indoor heat exchanger 20 is substantially integrated with the first heat exchanger 20A and the second heat exchanger 20B. Fulfill. Thereby, at the time of heating operation, the indoor heat exchanger 20 functions as a condenser, the outdoor heat exchanger 40 functions as an evaporator, and the room is heated. During the cooling operation, the outdoor heat exchanger 40 functions as a condenser, and the indoor heat exchanger 20 functions as an evaporator, thereby cooling the room.

  On the other hand, during the dehumidifying operation, the dry control valve 10 is in the throttled state shown in FIG. 1 and functions to throttle the refrigerant. If the flow path mode at this time is the cooling mode, the first heat exchanger 20A on the upstream side (high pressure side) functions as a condenser, and the second heat exchanger 20B on the downstream side (low pressure side) functions as an evaporator. Function. That is, the humidity can be lowered without lowering the room temperature by heating with the condenser and cooling / dehumidifying with the evaporator. In the heating mode (heating and wet operation), the functions of the first heat exchanger 20A and the second heat exchanger 20B are only reversed.

  Next, the structure and operation of the dry control valve 10 will be described. The dry control valve 10 includes a valve main body 1 and a drive unit 2. The valve main body 1 is formed with a cylindrical hollow valve chamber 1 a, and the valve chamber 1 a has a first port 11 opened on a side surface thereof and a first port 11 opened on a lower surface thereof. Two ports 12 are formed, and a main valve seat 1b is formed at the end of the second port 12 on the valve chamber 1a side. Two first joint pipes 3, 3 connected to the first heat exchanger 20A are connected to the first port 11, and two second joint pipes connected to the second heat exchanger 20B are connected to the second port 12. Two joint pipes 4 and 4 are connected.

  A switching valve 13 is slidably disposed in the valve chamber 1a, and a filter case 14 is disposed at the upper end of the valve chamber 1a. The filter case 14 accommodates a silent filter 14a and has an opening 14b. The switching valve 13 includes an upper cylindrical portion 13A that forms a space P (pressure control space) and a small-diameter portion 13B below the upper cylindrical portion 13A. A spring 16 disposed in the upper cylindrical portion 13A is provided around the filter case 14. The switching valve 13 is urged by the spring 16 toward the main valve seat 1b. Further, the peripheral edge of the lower end of the small diameter portion 13B of the switching valve 13 is a tapered surface 13a, and the tapered surface 13a contacts the main valve seat 1b when the switching valve 13 is seated. The small diameter portion 13B is formed with a horizontal first fixed aperture 13b and a second fixed aperture 13c that leads from the fixed aperture 13b to the space P in the upper cylindrical portion 13A.

  The drive unit 2 includes a lower case 2A fixed to the valve body 1 and a substantially cylindrical upper case 2B that seals the upper end of the lower case 2A. A bearing member 21 is disposed in the lower case 2A and the upper case 2B. The bearing member 21 is fixed to the upper inner peripheral surface of the lower case 2A with a noise filter 22 interposed between the lower case 2A and the lower end surface 2a. In the lower case 2 </ b> A, a space K (pressure control space) is formed on the outer periphery of the bearing member 21 and the silent filter 22. An opening 2 b is formed in a part of the lower end surface 2 a of the lower case 2 A, and a conduit 15 that connects the opening 2 b and the second port 12 is formed inside the valve body 1. As a result, the second port 12 and the space K are electrically connected.

  Inside the upper case 2A, a rotor 23 made of magnet is disposed. The rotor 23 is attached to a shaft 24 having a male screw 24a. The shaft 24 is a female screw portion 21a formed at the center of the bearing member 21. A male screw 24 a is screwed onto the shaft and is supported by the bearing member 21. A drive coil 25 is disposed on the outer periphery of the upper case 2 </ b> B, and the coil 25, the rotor 23, and the shaft 24 constitute a stepping motor 70. A cylindrical rotary stopper 31 is rotatably supported at the upper end of the shaft 24, and a fixed stopper 32 is suspended at one place inside the upper case 2B. As shown in FIG. 2 (B), the rotation stopper 31 is formed with vertical protrusions 31a and 31b on one inside and outside of the outer peripheral portion. A vertical protrusion 23a is formed on one inner side of the outer peripheral portion of the rotor 23. The protrusion 23a of the rotor 23 abuts on the protrusion 31b on the outer side of the rotation stopper 31, and the protrusion 31a on the inner side of the rotation stopper 31 is fixed. It is configured to abut against the stopper 32. Therefore, the rotor 23 stops approximately two counterclockwise rotations from the state of FIG. That is, the rotor 23 can be rotated in the range of approximately two rotations in the forward and reverse directions.

  A cylindrical cylinder portion 21b is formed below the female screw portion 21a of the bearing member 21, and a needle valve 26 as a “throttle valve” is disposed in the cylinder portion 21b. The needle valve 26 has a needle 26a at a lower end portion, and an upper portion thereof is a cylindrical portion, and a spring 27 is disposed therein. A ring-shaped stopper 26b is disposed in the cylindrical portion. On the other hand, a constricted portion 24b is formed at the lower portion of the shaft 24, and the shaft 24 and the needle valve 26 are connected via the constricted portion 24b and a stopper 26b. The needle 26a of the needle valve 26 is inserted into a variable throttle hole 28 formed in the center of the lower case 2A.

  With the above configuration, the dry control valve 10 operates as follows. By driving the stepping motor 70, the shaft 24 and the needle valve 26 are moved up and down according to the rotation direction, and the needle 26a and the variable throttle hole 28 are opened and closed. Specifically, in the state of FIG. 1, the needle 26 a closes the variable throttle hole 28, but when the shaft 24 rises from this state, the needle valve 26 initially closes the variable throttle hole 28 by the biasing force of the spring 27. Maintain the state. When the shaft 24 rises and the lower end of the constricted portion 24b reaches the position of the stopper 26b, the needle valve 26 rises together with the shaft 24, and the needle 24a moves away from the variable throttle hole 28. The gap between the needle 26a and the variable throttle hole 28 can be adjusted by controlling the rotation angle of the stepping motor 70 from this position, and the amount of refrigerant passing through the gap can be controlled. Thus, the needle valve 26 and the variable throttle hole 28 constitute a “variable throttle portion”.

  Here, the rotation range of the stepping motor 70 is the range of approximately two rotations of the rotor 23 as described above, and the variable throttle hole 28 is fully closed in the state of FIG. 2 (B). By turning clockwise, the variable throttle hole 28 is gradually opened. Then, the flow rate control of the refrigerant is performed within a predetermined range from the position shown in FIG. The other range is a fully open range in which the space P and the space K are equalized or a control range close to fully open. Note that the state in which the variable throttle hole 28 is fully opened is not changed in that the pressure in the pressure control space (space P and space K) is controlled by the throttle amount of the variable throttle portion as an embodiment of the claims. .

  Further, the switching valve 13 can be moved up and down in the valve chamber 1a of the valve body 1. As will be described later, the pressure of the space P, the pressure of the first port 11, the pressure of the second port 12, and the spring of the spring 16 are used. In response to the force, the switching valve 13 is seated or separated from the main valve seat 1b.

  In the state of FIG. 1, the first joint pipe 3 is on the high pressure side and the second joint pipe 4 is on the low pressure side, and the cooling and dehumidifying operation is about to be performed. Then, the refrigerant flows from the first joint pipe 3 into the dry control valve 10 and flows out from the second joint pipe 4. Since the variable throttle hole 28 (variable throttle portion) is closed, the switching valve 13 is seated on the main valve seat 1b. As the variable throttle hole 28 is opened, the refrigerant flows through the fixed throttles 13b, 13c → space P → silent filter 14a → variable throttle hole 28 → silent filter 22 → space K → conduit 15 → second joint pipe 4; Cooling dry operation. At this time, it is possible to control the dry flow rate by adjusting the gap between the variable throttle hole 28 and the needle 26a.

  When returning to the cooling operation, the variable throttle hole 28 is fully opened. As a result, the pressure in the space P becomes close to the pressure (low pressure) of the second joint pipe 4, and the switching valve 13 is moved to the main valve seat by the differential pressure between the pressure on the first port 11 side (high pressure) and the pressure in the space P. It leaves from 1b and it will be in a valve opening state. When switching from cooling to dehumidifying operation, the variable throttle hole 28 is once closed again. As a result, the pressure in the space P becomes high via the fixed throttles 13b and 13c, and the switching valve 13 is seated on the main valve seat 1b by the urging force of the spring 16, and the throttle state is established.

  Switching between heating operation and heating dehumidification operation is performed as follows. In the heating mode, the flow path switching valve 50 reverses the flow path of the refrigeration cycle 100, so that the first joint pipe 3 is on the low pressure side and the second joint pipe 4 is on the high pressure side. Therefore, the control of the variable aperture section is reversed. When the variable throttle hole 28 is fully opened, the pressure in the space P becomes close to the pressure (high pressure) in the second joint pipe 4, and the switching valve 13 is seated on the main valve seat 1b and is in the throttle state. Accordingly, the refrigerant flows through the second joint pipe 4 → conduit 15 → space K → silent filter 22 → variable throttle hole 28 → silent filter 14a → space P → fixed throttles 13c and 13b → first joint pipe 3 to heat and dehumidify. In this case as well, the flow rate can be controlled by the variable throttle.

  To return to the heating operation, the variable throttle hole 28 is closed. As a result, the pressure in the space P becomes close to the pressure (low pressure) of the first joint pipe 3, and the switching valve 13 is moved to the main valve seat by the differential pressure between the pressure on the second port 12 side (high pressure) and the pressure in the space P. It leaves from 1b and it will be in a valve opening state.

  Thus, the pressure acting above and below the variable throttle hole 28 may be a small differential pressure required for the operation of the switching valve, and the sectional area of the variable throttle hole 28 is small, so that the differential pressure resistance acting on the needle valve 26 is small. . Therefore, the stepping motor 70 may be a small motor. Further, since the switching valve 13 is pilot driven by the variable throttle portion, it is not necessary to increase the driving force even if the diameter of the main valve seat 1b is increased. Therefore, it is possible to obtain a small dry control valve that has low pressure loss during the cooling and heating operation, can perform the cooling and heating dehumidification control capable of controlling the refrigerant flow rate, and has a quiet sound during the dehumidifying operation.

  In addition, the seating conditions of the switching valve 13 are following Formula (1).

  However, P1, P2, and Pp are the pressure of the joint pipe 1, the pressure of the joint pipe 2, and the pressure of the space P, respectively, Ap is the horizontal sectional area of the space P, and Av is the horizontal sectional area of the valve seat. F is the spring force of the spring 16. Therefore, the switching valve 13 can be opened and closed if Pp is controlled by the variable throttle.

  The indoor heat exchanger of the air conditioner has two passes for the refrigerant piping in order to reduce pressure loss. Therefore, providing two refrigerant pipe connections like the first joint pipes 3 and 3 and the second joint pipes 4 and 4 of the dry control valve 10 of the embodiment contributes to space saving and cost saving of the indoor unit.

It is a figure which shows the principal part of the structure of the refrigerant | coolant flow control valve of embodiment of this invention, and the air conditioner to which this refrigerant | coolant flow control valve is applied. (A) is an AA arrow view (bottom view) of FIG. 1, and (B) is CC arrow sectional drawing.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Valve body 2 Drive part 3 1st joint pipe 4 2nd joint pipe 1a Valve chamber 11 1st port 12 2nd port 1b Main valve seat 13 Switching valve 14a Silent filter 15 Conduit 24 Shaft 23 Rotor 25 Coil 26 Needle valve 26a Needle 28 Variable throttle holes

Claims (5)

A method for switching and controlling a valve opening state in which a switching valve is driven to equalize pressure between two ports and a refrigerant is allowed to pass, and a throttle state for performing expansion of the refrigerant,
A switching valve opening and closing method, wherein a variable throttle valve that performs refrigerant flow rate control is used to control the pressure in a pressure control space to open and close the switching valve. A refrigerant flow rate control valve that controls a switching between a valve opening state in which a switching valve is driven to equalize pressure between two ports to pass the refrigerant and a throttle state for expansion of the refrigerant;
A valve chamber in which a first port and a second port are formed;
The second port is disposed in the valve chamber and is seated on a valve seat formed on the second port side to shield the second port and the first port, and the second port and the second port are separated from the valve seat. A switching valve for conducting the first port;
A fixed restricting portion for restricting a refrigerant flow between the first port and a pressure control space formed on the switching valve and separated by the switching valve on the side opposite to the valve seat;
A variable throttle portion that is arranged to be conductive to the pressure control space and communicates with the second port by a conduit, and variably restricts the flow of the refrigerant between the pressure control space and the conduit by a throttle valve;
A motor for controlling the throttle amount of the variable throttle unit by driving the throttle valve;
Controlling the pressure of the pressure control space by the amount of restriction of the variable restrictor, controlling the pressure difference between the pressure control space and the first port, and the pressure difference between the pressure control space and the second port; A refrigerant flow control valve characterized in that seating / separation of the switching valve is switched.   The refrigerant flow control valve according to claim 2, further comprising a silent filter on the pressure control space side and the conduit side of the throttle portion.   The refrigerant flow control valve according to claim 2 or 3, wherein the conduit is formed in a main body case constituting the valve chamber.   5. The refrigerant flow control valve according to claim 2, wherein two joint pipes communicated with the first port and two joint pipes communicated with the second port.

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