CN114458782B

CN114458782B - Electric valve and refrigeration cycle system

Info

Publication number: CN114458782B
Application number: CN202210297123.0A
Authority: CN
Inventors: 中川大树
Original assignee: Saginomiya Seisakusho Inc
Current assignee: Saginomiya Seisakusho Inc
Priority date: 2018-01-31
Filing date: 2019-01-03
Publication date: 2024-05-24
Anticipated expiration: 2039-01-03
Also published as: CN110094514B; CN114483980B; CN114458781B; CN114483980A; CN114458782A; JP6909740B2; JP2019132347A; CN114458781A; CN110094514A

Abstract

The invention provides an electric valve and a refrigeration cycle system, which can properly control the flow rate of a small flow rate control area in the electric valve with two-stage flow rate control areas. An electrically operated valve (10) is provided with: a main valve element (2) for opening and closing the main valve opening (1 d); a main valve spring (27) that biases the main valve element (2) in the closing direction; a sub valve element (3) for changing the opening of the sub valve port (24); and a sub valve spring (34) that biases the sub valve element (3) in the closing direction. In the small flow control region, the sub valve element (3) moves between a first position closest to the sub valve port (24) and a second position where the sub valve element (3) moves in the opening direction away from the sub valve port (24) and engages with the main valve element (2), and in the first position, the sub valve element (3) is not seated on the sub valve port (24), and the biasing force of the sub valve spring (34) does not act on the main valve element (2).

Description

Electric valve and refrigeration cycle system

The application is a divisional application; the application number of the parent case is '2019100040181', and the application name is 'electric valve and refrigeration cycle system'.

Technical Field

The present invention relates to an electrically operated valve and a refrigeration cycle system.

Background

Conventionally, as an electric valve provided in a refrigeration cycle of an air conditioner, there has been proposed a two-stage flow control region including a small flow control region in which a sub valve body is driven by an electric motor to advance and retract in an axial direction to control a flow rate of a main valve body at a sub valve port, and a large flow control region in which a main valve body opens and closes a main valve port of a valve chamber to control a flow rate (for example, see patent literature 1).

The electric valve (electric flow rate control valve) described in patent document 1 includes: a main valve element (second valve element) for opening and closing a main valve opening (large-diameter valve opening) of the valve chamber; a main valve spring (compression spring) for biasing the main valve element in the closing direction; a sub valve element (first valve element) for opening and closing a sub valve port (small diameter valve port) formed in a main valve element; a sub valve spring (valve closing buffer spring) that biases the sub valve element in the closing direction; and a drive unit having an electric motor (stepping motor) for driving the sub-valve element. In this motor-operated valve, the main valve spool biased by the main valve spring is seated to close the main valve port, and the sub valve spool biased by the sub valve spring is seated to close the sub valve port, thereby bringing about a fully closed state. In addition, the secondary valve port is opened by lifting the secondary valve spool by the driving portion, whereby the small flow rate control is performed. The lifted sub valve element is engaged with the main valve element to lift the main valve element, and the main valve port is opened, thereby performing a large flow control.

Prior art literature

Patent literature

Patent document 1: japanese patent No. 2898906

Disclosure of Invention

Problems to be solved by the invention

However, in the conventional electrically operated valve described in patent document 1, in the fully closed state in which both the main valve port and the sub valve port are closed, the urging force of the springs of both the main valve spring urging the main spool and the sub valve spring urging the sub valve spool acts on the main spool, and the main spool closes the main valve port due to such a combined urging force. Therefore, in the conventional electric valve, when the direction of action of the combined force is inclined with respect to the axis due to the difference in bending or inclination of the two springs, i.e., the main valve spring and the sub valve spring, the main valve body is not properly seated in the main valve port, and thus, there is a problem that the valve leakage of the main valve or the variation in the valve leakage amount becomes large easily occurs. If such a valve leak of the main valve occurs, the influence on the flow rate at the time of performing the small flow rate control to open the sub-valve port is large, and the flow rate cannot be throttled to a set small flow rate or the like, so that the flow rate in the small flow rate control cannot be strictly controlled.

The invention aims to provide an electric valve and a refrigeration cycle system, wherein the electric valve with two-stage flow control areas can properly control the flow rate of a small flow control area.

Means for solving the problems

The electric valve of the present invention comprises: a main valve body that opens and closes a main valve port of the valve chamber; a main valve spring for biasing the main valve element in a closing direction; a sub valve element that changes an opening degree of a sub valve port provided in the main valve element; a sub valve spring for biasing the sub valve element in a closing direction; and a driving unit that drives the sub valve element to advance and retreat in an axial direction, wherein the electric valve includes a two-stage flow control region, that is, a small flow control region in which the sub valve element changes an opening degree of the sub valve port, and a large flow control region in which the main valve element opens and closes the main valve port, and wherein the electric valve is characterized in that in the small flow control region, the sub valve element moves between a first position closest to the sub valve port and a second position in which the sub valve element is moved in an opening direction away from the sub valve port by a driving force of the driving unit to engage with the main valve element, and in the large flow control region, the main valve element moves between a closed position in which the sub valve element is biased in a closing direction by the main valve spring to be seated on the main valve port and an open position in which the sub valve element is moved in the second position by the driving force of the driving unit to open the main valve port, and in that in the first position, the sub valve element is not in the sub valve port, and the biasing force of the sub valve spring does not act on the main valve element.

According to the above-described invention, in the first position, the sub valve element is not seated on the sub valve port, and the biasing force of the sub valve spring does not act on the main valve element, so that the biasing force of the main valve spring can act on the main valve element seated on the main valve port in the closed position, but the biasing force of the sub valve spring does not act. Therefore, the combined biasing force of the main valve spring and the sub valve spring does not act on the main valve body, and the main valve body can be properly seated on the main valve port by only the biasing force of the main valve spring, so that the valve leakage of the main valve is less likely to occur. Since the valve leakage of the main valve is less likely to occur, the influence on the flow rate at the time of small flow rate control for opening the sub-valve port can be reduced, and the flow rate in the small flow rate control region can be appropriately controlled.

In this case, it is preferable that a flow path is formed between the sub valve element and the sub valve port in the first position.

According to this configuration, since the flow path is formed between the sub valve element and the sub valve port, the valve-opening type electric valve that always ensures the flow rate by the flow path can be constructed. Such an open valve type electric valve can be suitably used in an air conditioner having a dehumidification function, such as a household air conditioner.

The flow path is preferably formed by a gap between an outer peripheral surface of the sub valve element and an inner peripheral surface of the sub valve port.

Preferably, the sub valve body has a cylindrical portion, and the flow path is formed by a gap between an outer peripheral surface of the cylindrical portion and an inner peripheral surface of the sub valve port.

According to this configuration, the flow path is formed by the gap between the outer peripheral surface of the sub valve element (in particular, the outer peripheral surface of the cylindrical portion) and the inner peripheral surface of the sub valve port, so that the opening area of the flow path can be strictly defined, and a small flow rate when the sub valve element is positioned at the first position can be appropriately ensured.

The driving unit preferably includes: an electric motor having a magnetic rotor; and a stopper mechanism for restricting rotation of the magnetic rotor, wherein the first position of the sub valve element is defined by a lowermost position of the magnetic rotor restricted by the stopper mechanism.

According to this configuration, the first position of the sub valve element is defined by the lowermost position of the magnetic rotor, and the rotation of the magnetic rotor is restricted by the stopper mechanism at the lowermost position, so that the sub valve element can be reliably stopped at the first position, and an excessive load can be prevented from acting on the main valve element.

The refrigeration cycle system according to the present invention is a refrigeration cycle system including a compressor, a condenser, an expansion valve, and an evaporator, wherein the expansion valve is provided by using any of the above-described electrically operated valves.

According to such a refrigeration cycle system, as in the case of the above-described electric valve, it is possible to reduce the influence on the flow rate at the time of the small flow rate control for opening the sub-valve port by making it difficult to cause the valve leakage of the main valve, and to appropriately control the flow rate in the small flow rate control region in the refrigeration cycle using the electric valve as the expansion valve.

ADVANTAGEOUS EFFECTS OF INVENTION

According to the electric valve and the refrigeration cycle system of the present invention, in the electric valve having the two-stage flow rate control region, the flow rate of the small flow rate control region can be appropriately controlled.

Drawings

Fig. 1 is a longitudinal sectional view showing a fully closed state of an electrically operated valve according to a first embodiment of the present invention.

Fig. 2 is a longitudinal sectional view showing the fully opened state of the above-described electric valve.

Fig. 3 (a) to (B) are longitudinal sectional views showing a part of the above-described electrically operated valve in an enlarged manner.

Fig. 4 (a) to (B) are graphs showing the relationship between the valve opening degree and the flow rate of the electric valve.

Fig. 5 is a longitudinal sectional view showing a fully closed state of an electrically operated valve according to a second embodiment of the present invention.

Fig. 6 is a longitudinal sectional view showing the fully opened state of the above-described electric valve.

Fig. 7 (a) to (B) are longitudinal sectional views showing a part of the above-described electrically operated valve in an enlarged manner.

Fig. 8 is a schematic configuration diagram showing the refrigeration cycle system according to the present invention.

In the figure:

10. 10A, 10B-electric valve, 1 d-main valve port, 2-main valve core, 3-sub valve core, 4-driving part, 24-sub valve port, 24 a-inner peripheral surface, 27-main valve spring, 34-sub valve spring, 35-cylindrical part, 35 a-outer peripheral surface, 41-step motor (electric motor), 43-limit mechanism, 44-magnetic rotor, 91-first indoor side heat exchanger, 92-second indoor side heat exchanger, 93-compressor, 95-outdoor side heat exchanger, R-flow path.

Detailed Description

An electrically operated valve according to a first embodiment of the present invention will be described with reference to fig. 1 to 4. As shown in fig. 1 and 2, an electrically operated valve 10 (10A) according to the first embodiment includes a valve housing 1, a main valve body 2, a sub valve body 3, and a driving unit 4. The concept of "up and down" in the following description corresponds to up and down in the drawings of fig. 1 and 2.

The valve housing 1 has a cylindrical valve body 1a and a bearing member 1b fixed to the valve body 1 a. The valve body 1A has a cylindrical valve chamber 1A formed therein, and the valve body 1A is provided with a primary connection pipe 11 communicating with the valve chamber 1A from the side surface side to allow the refrigerant to flow in, and a secondary connection pipe 12 communicating with the valve chamber 1A from the bottom surface side to allow the refrigerant to flow out. A main valve seat 1c is formed in the valve body 1A at a position where the valve chamber 1A communicates with the secondary joint pipe 12, and a main valve port 1d having a circular cross-sectional shape is formed from the main valve seat 1c to the secondary joint pipe 12 side. A substantially cylindrical fitting portion 1e is provided at an upper portion of the valve body 1a, and a bearing member 1b is fitted into the fitting portion 1e, and an upper end portion of the fitting portion 1e is swaged inward, whereby the valve body 1a and the bearing member 1b are integrally fastened. The valve housing 1 (the valve body 1a and the bearing member 1 b) is made of Brass (Brass).

A main valve guide 1B having a cylindrical shape is formed in the valve body 1a, and a main valve element 2 is disposed in the main valve guide 1B. The main valve body 2 includes a valve main body 2A, a spring holder 2B, and a sub-valve seat 2C, and the valve main body 2A includes a main valve portion 21 that is seated on and unseated from the main valve seat 1C. The upper portion of the valve body 2A is a holding portion 22 forming a substantially cylindrical fitting hole, and the spring holder 2B is fitted into the holding portion 22, and the upper end 22A of the holding portion 22 is swaged inward, whereby the valve body 2A and the spring holder 2B are integrally fastened. The main spool 2 (valve body 2A, spring holder 2B, and sub-valve seat 2C) is made of brass.

A sub-valve chamber 23 is formed in the valve body 2A, and a sub-valve port 24 is formed to penetrate the interior of the sub-valve seat 2C along the axis L. The sub-valve seat 2C is fixed to the inside of the lower end side of the valve main body 2A. The valve body 2A has a substantially cylindrical shape, and has a through hole 25 formed in both side surfaces thereof, and the sub valve chamber 23 communicates with the valve chamber 1A in the main valve guide 1B through the through hole 25. An insertion hole 26 along the axis L is formed in the spring holder portion 2B, and the sub-valve body 3 is inserted into the insertion hole 26. A main valve spring 27 is disposed between the upper surface of the spring holder portion 2B and the lower surface of the bearing member 1B, and the main valve element 2 is biased in the main valve seat 1c direction (closing direction) by the main valve spring 27.

The sub valve body 3 is composed of a cylindrical rod-shaped sub valve shaft 31, an E-ring 32, a thrust washer 33, and a sub valve spring 34. The sub valve shaft 31 and the E-ring 32 of the sub valve body 3 are made of stainless steel, and the thrust washer 33 is made of phosphor bronze. A groove for fitting the E-ring 32 is formed near the lower end of the sub valve shaft 31, and a small diameter portion 31a that is inserted into the sub valve spring 34 is formed on the upper end side of the sub valve shaft 31. The sub valve shaft 31 is inserted through the guide hole 13 of the bearing member 1b and the insertion hole 26 of the main valve element 2, and is supported so as to be movable in the vertical direction along the axis L and rotatable about the axis L. The thrust washer 33 can abut against the upper surface of the E-ring 32 and the lower surface of the spring holder portion 2B, and the friction force between the abutting surfaces thereof becomes extremely small. The sub valve spring 34 is disposed between the rotor support plate 44a of the drive section 4 and the stepped portion of the small diameter portion 31a of the sub valve shaft 31, and the sub valve element 3 is biased in the sub valve seat 2C direction (closing direction) with respect to the magnetic rotor 44 by the sub valve spring 34.

A fixing member 14 is fixed to the upper end of the valve housing 1 by welding or the like, and a housing 15 is hermetically fixed to the fixing member 14 by welding or the like. The driving unit 4 includes: a stepping motor 41 as an electric motor; a screw feed mechanism 42 for advancing and retreating the sub-valve body 3 by rotation of the stepping motor 41; and a stopper mechanism 43 that restricts rotation of the stepping motor 41.

The stepping motor 41 of the driving unit 4 includes: a magnetic rotor 44 whose outer peripheral portion is magnetized to be multipolar; and a stator coil 45 disposed on the outer periphery of the housing 15. The stepping motor 41 rotates the magnetic rotor 44 according to the number of pulses by giving a pulse signal to the stator coil 45. An abutment plate 31b is fixed to the upper end portion of the sub valve shaft 31 by welding or the like, and the abutment plate 31b abuts against the upper surface of the rotor support plate 44 a. Further, a cylindrical sleeve 31c is provided in the small diameter portion 31a of the sub valve shaft 31, and the urging force of the sub valve spring 34 acts between the rotor support plate 44a and the sub valve shaft 31 via the sleeve 31c, whereby the rotor support plate 44a is sandwiched between the sleeve 31c and the abutment plate 31 b.

The screw feed mechanism 42 includes: a cylindrical female screw member 47 fixed to the rotor support plate 44a on the inner peripheral side of the magnetic rotor 44; and a male screw member 46 provided in a threaded engagement with the inner side of the female screw member 47 and fixed to the cylindrical recess 1ba of the bearing member 1 b. When the magnetic rotor 44 rotates, the female screw member 47 rotates around the male screw member 46, and the female screw member 47 moves in the direction of the axis L according to the pitch, whereby the magnetic rotor 44 advances and retreats in the direction of the axis L. Here, the magnetic rotor 44 descends in accordance with the forward rotation thereof, and the sub valve element 3 descends in accordance with the descent. On the other hand, the magnetic rotor 44 rises in accordance with the reverse rotation thereof, and the abutment plate 31b is pressed by the rotor support plate 44a in accordance with the rise, whereby the sub valve body 3 also rises.

As described above, the sub valve body 3 is biased downward by the sub valve spring 34, and thereby the sub valve body 3 is swingably supported with respect to the magnetic rotor 44 with the nip portion between the sleeve 31c and the abutment plate 31b as a fulcrum. When the sub valve body 3 is lifted or lowered by the rotation of the magnetic rotor 44 and the screw feed mechanism 42, even if the sub valve body 3 collides with the sub valve port 24, the guide hole 13, and the insertion hole 26, the sub valve body 3 is released by the rocking mechanism of the sub valve spring 34, so that friction force can be made difficult to act on the rubbed portion. Therefore, the drive torque of the drive unit 4 can be reduced, and wear of the sub valve element 3, the sub valve port 24, and the like can be prevented.

The stopper mechanism 43 includes: a columnar rod-like guide 48 hanging from a ceiling portion of the housing 15; a guide wire body 49 fixed to the outer periphery of the guide 48; and a movable slider 50 which is guided by the guide wire body 49 to rotate and can move up and down. The movable slider 50 is provided with a claw portion 51 protruding radially outward, and the magnetic rotor 44 is provided with an extension portion 44b extending upward and abutting the claw portion 51, and when the magnetic rotor 44 rotates, the extension portion 44b presses the claw portion 51, whereby the movable slider 50 rotates along with the guide wire body 49 and moves up and down.

The guide wire body 49 is formed with: an upper limit portion 49a defining the uppermost position of the magnetic rotor 44; and a lower end stopper 49b defining the lowermost position of the magnetic rotor 44. When the end of the movable slider 50 on the opposite side of the end of the claw portion 51 from the end of the movable slider 50 that descends in accordance with the forward rotation of the magnetic rotor 44 contacts the lower end stopper portion 49b, the movable slider 50 cannot rotate at the contact position, and thereby the rotation of the magnetic rotor 44 is restricted, and the descent of the sub-valve body 3 is stopped. On the other hand, if the claw portion 51 of the movable slider 50 that rises with the reverse rotation of the magnetic rotor 44 comes into contact with the upper end stopper portion 49a, the movable slider 50 cannot rotate at the contact position, and thereby the rotation of the magnetic rotor 44 is restricted, and the rise of the sub-valve body 3 is also stopped.

Hereinafter, a detailed structure and operation of the electrically operated valve 10A will be described with reference to fig. 3 (a) to (B) and 4 (a) to (B). Fig. 3 (a) to (B) are longitudinal sectional views each showing an enlarged portion of the motor-operated valve 10A, and are longitudinal sectional views each showing an enlarged front end portion of the sub valve body 3 and the sub valve seat 2C. Fig. 4 (a) to (B) are graphs showing the relationship between the valve opening degree and the flow rate of the electric valve 10A.

As shown in fig. 3 (a) to (B), the front end of the sub valve shaft 31 of the sub valve body 3 is formed to have: a cylindrical portion 35 having a smaller diameter than an end portion of the sub valve shaft 31; and a truncated cone portion 36 having a diameter gradually smaller toward the tip than the cylindrical portion 35. The diameter of the cylindrical portion 35 is smaller than the inner diameter of the sub-valve port 24 of the sub-valve seat 2C, and a passage R through which the refrigerant passes is formed by a gap between the outer peripheral surface 35a of the cylindrical portion 35 and the inner peripheral surface 24a of the sub-valve port 24. Fig. 3a shows the sub valve element 3 positioned closest to the sub valve port 24 (first position) corresponding to the lowest end position of the magnetic rotor 44. Fig. 3B shows the position where the sub valve body 3 is lifted from the first position by the rotation of the magnetic rotor 44 and the thrust washer 33 is in contact with the lower surface of the spring holder portion 2B, that is, the sub valve body 3 located at the position (second position) where it is engaged with the main valve body 2.

The above-described electrically operated valve 10A operates as follows. First, in the state of fig. 1 and 3 (a), the main valve portion 21 of the main valve element 2 is seated on the main valve seat 1c, and the main valve opening 1d is closed. On the other hand, the sub valve body 3 located at the first position closest to the sub valve port 24 is not seated on the sub valve seat 2C, and the flow path R is formed by a gap between the outer peripheral surface 35a of the cylindrical portion 35 of the sub valve body 3 and the inner peripheral surface 24a of the sub valve port 24. Therefore, the refrigerant flowing from the primary joint pipe 11 into the valve chamber 1A and flowing from the through hole 25 into the secondary valve chamber 23 flows from the flow path R through the secondary valve port 24 to the lower side of the main valve portion 21, and flows from the main valve port 1d toward the secondary joint pipe 12. That is, as shown in fig. 4 (a) to (B), even if the valve opening is zero, a minute flow rate is generated.

Next, by driving the stepping motor 41 of the driving unit 4 to reversely rotate the magnetic rotor 44 to raise the sub valve body 3, as shown in fig. 3 (B), the cylindrical portion 35 of the sub valve body 3 is pulled out from the sub valve port 24, and the flow path R is formed by the gap between the conical portion 36 of the sub valve body 3 and the inner peripheral surface 24a of the sub valve port 24. Here, since the diameter of the conical portion 36 gradually decreases, the gap between the conical portion and the inner peripheral surface 24a of the sub-valve port 24 increases, and the flow path R expands, as shown in fig. 4, and the flow rate gradually increases. At this time, the main valve portion 21 of the main valve element 2 continues to be seated on the main valve seat 1c, and the flow rate increases slightly before the second position where the sub valve element 3 engages with the main valve element 2. In this way, the control region in which the opening degree is changed by moving the sub valve element 3 between the first position and the second position is a small flow rate control region in which the flow rate is extremely small with respect to the change in the opening degree of the sub valve element 3 (rotation amount of the stepping motor 41=valve lift amount).

Then, when the sub valve body 3 that has been raised to the second position and engaged with the main valve body 2 is further raised, as shown in fig. 2, the main valve body 2 is lifted by the sub valve body 3, and the main valve portion 21 is separated from the main valve seat 1c to open the valve. As described above, the control region in which the main valve element 2 is raised from the seated position (closed position) toward the valve opening position (open position) is a large flow rate control region in which the flow rate is greatly changed with respect to the opening degree of the main valve element 2 (rotation amount of the stepping motor 41=valve lift amount). In the fully open state shown in fig. 2, in which the main valve element 2 is raised to the valve opening position, the flow rate is maximized. Here, as the flow rate in the fully opened state, the opening area of the gap between the main valve portion 21 and the main valve seat 1c is equal to or larger than the opening area of the primary joint pipe 11 and the secondary joint pipe 12, and the opening degree of the electric valve 10A, which is a state in which the flow rate is not throttled by the main valve portion 21 and the main valve port 1d, is set so as to function as a simple flow path.

Here, the lift amount of the sub-valve element 3 in the small flow rate control region is preferably set to be equal to or less than one pitch amount (that is, one rotation of the magnetic rotor 44 of the stepping motor 41=80 pulses) with respect to the pitches of the female screw member 47 and the male screw member 46 of the screw feed mechanism 42, and is set to be from the first position to the second position. In this case, a pitch amount of, for example, 0.5mm is preferred. By setting the lift amount of the sub valve body 3 as described above, the ratio of the sub valve control range (small flow rate control region) can be set to a fixed ratio or less with respect to the entire control range (small flow rate control region+large flow rate control region), and the full open flow rate when the main valve portion 21 is open can be ensured. Here, the sub valve control range (the lift amount of the sub valve element 3) is preferably 20% or less of the entire control range (the full lift amount).

That is, when the lift amount of the sub valve element 3 exceeds one pitch amount, as shown in the surrounding portion a in fig. 4 (a), the main valve portion 21 may not be completely pulled out from the main valve seat 1c at the full open position, and the set full open flow rate may not be obtained. In contrast, if the lift amount of the sub-valve body 3 is set to one pitch amount or less, as shown by the surrounding portion B in fig. 4 (B), the main valve portion 21 is completely pulled out from the main valve seat 1c at the fully open position, and even if there is a deviation at the start point of the valve opening due to manufacturing error, assembly error, or the like of each component, the deviation of the fully open flow rate can be suppressed by fully opening the main valve portion 21.

According to the present embodiment described above, in the first position in the fully closed state, the sub valve body 3 is not seated on the sub valve port 24, and the biasing force of the sub valve spring 34 does not act on the main valve body 2, so that the biasing force of the main valve spring 27 acts on the main valve body 2 seated on the main valve port 1d, but the biasing force of the sub valve spring 34 does not act. Therefore, the combined biasing force of the main valve spring 27 and the sub valve spring 34 does not act on the main valve body 2, and the main valve body 2 can be properly seated in the main valve port 1d only by the biasing force of the main valve spring 27, so that the valve leakage of the main valve is less likely to occur. Since the valve leakage of the main valve is less likely to occur, the influence on the flow rate at the time of small flow rate control in which the sub-valve port 24 is opened can be reduced, and the flow rate in the small flow rate control region can be appropriately controlled. At this time, although the urging force of the sub valve spring 34 is not applied to the sub valve port 24, as described above, the sub valve spring 34 has a function of preventing a decrease in valve driving torque, abrasion of the sub valve body 3, the sub valve port 24, and the like.

In addition, by forming the flow path R by the gap between the outer peripheral surface 35a of the cylindrical portion 35 of the sub valve body 3 located at the first position and the inner peripheral surface 24a of the sub valve port 24, the valve-opening type electric valve 10 that always ensures the flow rate by the flow path R can be constructed. The electric valve 10 of the valve opening type can be suitably used in an air conditioner having a dehumidification function, such as a household air conditioner. Further, by forming the flow path R by the gap between the outer peripheral surface 35a of the cylindrical portion 35 and the inner peripheral surface 24a of the sub valve port 24, the opening area of the flow path R can be strictly defined, and a small flow rate when the sub valve element 3 is positioned at the first position can be appropriately ensured.

The first position of the sub valve element 3 is defined by the lowermost position of the magnetic rotor 44, and the rotation of the magnetic rotor 44 is restricted by the stopper mechanism 43 at the lowermost position, so that the sub valve element 3 can be reliably stopped at the first position, and an excessive load can be prevented from acting on the main valve element 2.

An electrically operated valve according to a second embodiment of the present invention will be described below with reference to fig. 5 to 7. As shown in fig. 5 and 6, the electrically operated valve 10 (10B) of the second embodiment includes a valve housing 1, a main valve body 2, a sub valve body 3, and a driving unit 4, as in the electrically operated valve 10A of the first embodiment. The following will explain the differences from the first embodiment, and the same or similar structures as those of the first embodiment will be omitted or briefly described.

The valve housing 1 includes a tubular valve body 1a and a support member 16 fixed to the inside of the valve body 1a. The support member 16 is welded and fixed to the valve body 1a by a metal fixing portion 16 a. The support member 16 is a resin molded product, and is formed to have a cylindrical main valve guide portion 16b provided on the main valve seat 1c side, and a female screw portion 16c provided on the driving portion 4 side and having a female screw formed on the inner peripheral surface.

The main valve body 2 includes a valve body portion 2A, a spring holder portion 2B, and a sub-valve seat 2C. A sub-valve chamber 23 is formed in the valve body 2A, and a sub-valve port 24 is formed to penetrate the interior of the sub-valve seat 2C along the axis L. A through hole 25 is formed in both side surfaces of the valve body 2A, and the sub-valve chamber 23 communicates with the valve chamber 1A through the through hole 25. The spring bracket portion 2B is formed in an annular shape, and a rotor shaft 52 is inserted therein. A main valve spring 27 is disposed between the upper surface of the spring holder portion 2B and the ceiling surface of the support member 16, and the main valve element 2 is biased in the main valve seat 1c direction (closing direction) by the main valve spring 27.

The sub valve body 3 is composed of a cylindrical sub valve cylinder 37, a sub valve portion 38 protruding downward from the sub valve cylinder 37, a thrust washer 33 provided on the upper side of the sub valve cylinder 37, and a sub valve spring 34 provided inside the sub valve cylinder 37. The sub-valve cylinder 37 is inserted into the insertion hole 26 of the main valve element 2, and is supported so as to be movable in the vertical direction along the axis L and rotatable about the axis L. The thrust washer 33 can abut against the upper surface of the sub-valve cylinder 37 and the lower surface of the spring holder portion 2B, and the friction force between the abutting surfaces becomes extremely small. An insertion hole is provided in the upper portion of the sub-valve cylinder 37, through which the rotor shaft 52 is inserted, and the sub-valve spring 34 is disposed between a flange portion 52c formed at the lower end portion of the rotor shaft 52 and an upper end portion 38a of the sub-valve portion 38 joined to the bottom surface portion of the sub-valve cylinder 37. The sub valve element 3 is biased in the sub valve seat 2C direction (closing direction) with respect to the rotor shaft 52 (magnetic rotor 44) by the sub valve spring 34.

As described above, the sub valve body 3 is biased downward by the sub valve spring 34, and thereby the sub valve cylinder 37 and the sub valve body 3 are swingably supported with respect to the magnetic rotor 44 and the rotor shaft 52 with the flange portion 52c of the rotor shaft 52 as a fulcrum. When the sub valve body 3 is lifted or lowered by the rotation of the magnetic rotor 44 and the screw feed mechanism 42, even if the sub valve body 3 collides with the sub valve port 24 and the insertion hole 26, the sub valve body 3 is released by the rocking mechanism of the sub valve spring 34, so that friction force can be hardly applied to the collision portion. Therefore, the drive torque of the drive unit 4 can be reduced, and wear of the sub valve element 3, the sub valve port 24, and the like can be prevented.

The driving unit 4 includes: a stepping motor 41 as an electric motor; a screw feed mechanism 42 for advancing and retreating the sub-valve body 3 by rotation of the stepping motor 41; and a stopper mechanism 43 that restricts rotation of the stepping motor 41. The stepping motor 41 includes a magnetic rotor 44, a stator coil 45, and a rotor shaft 52 fixed to the magnetic rotor 44. The rotor shaft 52 is fixed to the magnetic rotor 44 via a fixing member 52a, extends along the axis L, and has an upper end inserted into the guide 48 of the stopper mechanism 43. A male screw portion 52b is integrally formed in the intermediate portion of the rotor shaft 52, and the male screw portion 52b is screwed with the female screw portion 16c of the support member 16, thereby constituting the screw feed mechanism 42.

The detailed structure of the motor-operated valve 10B will be described below with reference to fig. 7 (a) to (B). Fig. 7 (a) to (B) are longitudinal sectional views enlarged to show a part of the electric valve 10B, and are longitudinal sectional views enlarged to show the front end portions of the main valve body 2 and the sub valve body 3, and the main valve seat 1C and the sub valve seat 2C, respectively.

As shown in fig. 7 (a) to (B), the front end of the sub valve portion 38 of the sub valve body 3 is formed to have a cylindrical portion 35 having a diameter smaller than the inner diameter of the sub valve port 24 of the sub valve seat 2C, and a circular truncated cone portion 36, and a flow path R through which the refrigerant passes is formed by a gap between the outer peripheral surface 35a of the cylindrical portion 35 and the inner peripheral surface 24a of the sub valve port 24. Fig. 7 a shows the sub valve element 3 positioned closest to the sub valve port 24 (first position) corresponding to the lowest end position of the magnetic rotor 44. Fig. 7B shows the sub valve body 3 raised from the first position by the rotation of the magnetic rotor 44, and the sub valve body 3 is positioned at a position where the thrust washer 33 abuts against the lower surface of the spring holder portion 2B, that is, at a position (second position) where it engages with the main valve body 2.

According to the present embodiment described above, the same operational effects as those of the first embodiment can be achieved. That is, in the first position in the fully closed state, the urging force of the sub-valve spring 34 does not act on the main valve element 2, and thus the combined urging force of the main valve spring 27 and the sub-valve spring 34 does not act on the main valve element 2 seated in the main valve port 1d, and the main valve element 2 can be properly seated against the main valve port 1d only by the urging force of the main valve spring 27, so that the valve leakage of the main valve is less likely to occur. Since the valve leakage of the main valve is less likely to occur, the influence on the flow rate at the time of small flow rate control in which the sub-valve port 24 is opened can be reduced, and the flow rate in the small flow rate control region can be appropriately controlled. Although the biasing force of the sub valve spring 34 is not applied to the sub valve port 24, the sub valve spring 34 functions to prevent the valve driving torque from decreasing and the sub valve element 3, the sub valve port 24, and the like from being worn as described above.

The refrigeration cycle system according to the present invention will be described below with reference to fig. 8. The refrigeration cycle 90 is used in, for example, an air conditioner such as a household air conditioner. The electric valve 10 according to the first and second embodiments is provided between a first indoor heat exchanger 91 (operating as a dehumidification cooler) and a second indoor heat exchanger 92 (operating as a dehumidification heater) of an air conditioner, and constitutes a heat pump refrigeration cycle together with a compressor 93, a four-way valve 94, an outdoor heat exchanger 95, and an electronic expansion valve 96. The first indoor heat exchanger 91, the second indoor heat exchanger 92, and the electric valve 10 are installed indoors, and the compressor 93, the four-way valve 94, the outdoor heat exchanger 95, and the electronic expansion valve 96 are installed outdoors, thereby constituting a cooling/heating device.

The present invention is not limited to the above-described embodiments, and other configurations, etc. that can achieve the object of the present invention are included, and modifications, etc. as shown below are also included in the present invention. For example, in the above embodiment, the electric valve 10 used for an air conditioner such as a home air conditioner is exemplified, but the electric valve of the present invention is not limited to a home air conditioner, and may be applied to a business air conditioner, not limited to an air conditioner, but also applicable to various refrigerators and the like.

In the above-described embodiment, the screw feed mechanism 42 is constituted by the female screw member 47 and the male screw member 46 (first embodiment), or by the male screw portion 52b of the rotor shaft 52 and the female screw portion 16c of the support member 16 (second embodiment), and the structure of the screw feed mechanism for driving the sub-valve body 3 to advance and retreat is not limited to that of the above-described embodiment, and any structure can be employed. The mechanism for driving the sub valve element to advance and retreat is not limited to the screw feed mechanism, and an appropriate mechanism may be applied.

In the above embodiment, the stopper mechanism 43 is constituted by the guide 48, the guide wire body 49, and the movable slider 50 provided on the ceiling portion of the housing 15, but the arrangement position and structure thereof are not particularly limited as long as the rotation of the magnetic rotor 44 can be restricted. For example, a stopper mechanism may be provided on the inner side and the lower side of the magnetic rotor. In the above embodiment, the description has been made of the fact that the refrigerant flows in from the primary joint pipe 11 and flows out from the secondary joint pipe 12, but the present invention is not limited to one-way flow, and the present invention can be applied to a case where the refrigerant flows in from the secondary joint pipe 12 and flows out from the primary joint pipe 11, and in particular, a case where the reverse flow is performed in a fully opened state.

Although the embodiments of the present invention have been described in detail with reference to the drawings, specific configurations are not limited to the embodiments, and modifications of design and the like, which do not depart from the gist of the present invention, are also included in the present invention.

Claims

1. An electrically operated valve, comprising:

a valve body to which an external screw member is fixed;

a main valve body that opens and closes a main valve port of the valve chamber;

a sub valve element that changes an opening degree of a sub valve port provided in the main valve element;

a biasing spring disposed between the upper stepped surface of the sub valve shaft and the rotor support member, and biasing the sub valve element in a closing direction; and

A driving part which drives the auxiliary valve core to advance and retreat in the axial direction through the combination of the external thread and the internal thread and the rotation of the internal thread,

The electric valve has a two-stage flow control region, namely, a small flow control region in which the sub valve element changes the opening of the sub valve port and a large flow control region in which the main valve element opens and closes the main valve port,

The above-mentioned electric valve is characterized in that,

In the small flow control region, the sub valve element moves between a first position closest to the sub valve port and a second position where the sub valve element is engaged with the main valve element by moving in a direction away from the sub valve port by a driving force of the driving portion,

In the large flow control region, the main valve element moves between a closed position where the main valve opening is seated and an open position where the main valve opening is opened by integrally moving the sub valve element to the second position by a driving force of the driving portion,

In the first position, the secondary spool is not seated on the secondary valve port,

The main valve spool includes a valve body portion having an auxiliary valve chamber formed therein and an auxiliary valve seat fixed to the lower end side of the valve body portion, the auxiliary valve seat being located closer to the main valve port than the auxiliary valve chamber of the valve body portion, an outer peripheral portion of the auxiliary valve seat, which is a length of the auxiliary valve port in an axial direction, being fixed to the valve body portion, and the valve body portion being guided by a cylindrical main valve guide portion.

2. The electrically operated valve as set forth in claim 1, wherein,

In the first position, a flow path is formed between the sub valve element and the sub valve port.

3. The electrically operated valve as set forth in claim 2, wherein,

The flow path is formed by a gap between an outer peripheral surface of the sub valve element and an inner peripheral surface of the sub valve port.

4. The electrically operated valve as set forth in claim 3, wherein,

The sub valve body has a cylindrical portion, and the flow path is formed by a gap between an outer peripheral surface of the cylindrical portion and an inner peripheral surface of the sub valve port.

5. The electrically operated valve as claimed in any one of claims 1 to 4, wherein,

The driving unit includes: an electric motor having a magnetic rotor; and a limit mechanism for limiting the rotation of the magnetic rotor,

The first position of the sub valve element is defined by a lowermost position of the magnetic rotor limited by the limiting mechanism.

6. A refrigeration cycle system includes a compressor, a condenser, an expansion valve, and an evaporator,

The above-described refrigeration cycle system is characterized in that,

The use of the electrically operated valve according to any one of claims 1 to 5 as the expansion valve.