JP6659624B2 - Motorized valve and refrigeration cycle system - Google Patents

Description

  The present invention relates to a motor-operated valve for controlling a flow rate of a refrigerant in an air conditioner or the like, and more particularly, to an electric valve and a refrigeration cycle system in which the shape of a valve port for a needle valve is improved.

  2. Description of the Related Art Conventionally, in a refrigeration cycle system, noise caused by passage of a refrigerant, which is generated from an electric valve that controls the flow rate of a refrigerant, often causes a problem. An example of a motor-operated valve adapted to take such a noise countermeasure is disclosed in Japanese Patent Application Laid-Open No. 2013-234726 (Patent Document 1).

  The motor-operated valve of Patent Literature 1 has a primary joint pipe communicating from the side of the valve housing to the valve chamber, and a secondary joint pipe communicating from the lower end of the valve housing to the valve chamber via the valve port. ing. Then, for example, during a heating operation of the refrigeration cycle system, the refrigerant flows into the valve chamber from the primary joint pipe, and flows out of the valve chamber to the secondary joint pipe via a gap between the needle valve and the valve port. On the other hand, during the cooling operation, the refrigerant flows into the valve chamber from the secondary joint pipe via the gap between the needle valve and the valve port, and flows out from the valve chamber to the primary joint pipe.

  The motor-operated valve of Patent Document 1 improves the shape of the valve port so as to reduce the refrigerant passage noise when the refrigerant flows out of the valve chamber to the secondary joint pipe.

JP 2013-234726 A

  The motor-operated valve disclosed in Patent Document 1 has an effect of reducing noise in a state where refrigerant flows out of the valve chamber to the secondary joint pipe through a gap between the needle valve and the valve port. No consideration is given to the reverse refrigerant passing noise or the like, in which the refrigerant flows into the valve chamber through the gap between the valve and the valve port, and there is room for improvement. For example, the refrigerant flowing into the valve port from the secondary joint pipe side concentrates in the gap between the needle valve and the valve port, the differential pressure increases, and the vibration of the needle valve is easily excited and noise is easily generated.

  The present invention is directed to a state in which a refrigerant flows into a valve chamber from a primary joint pipe, a state in which the refrigerant flows out of the valve chamber to a secondary joint pipe through a gap between the needle valve and the valve port, and a state in which the needle valve flows from the secondary joint pipe. It is an object to provide a motor-operated valve in which noise such as a refrigerant passing sound is reduced with respect to a two-way flow in a state where a refrigerant flows into a valve chamber through a gap between the valve and a valve port.

The motor-operated valve according to claim 1, wherein the valve chamber to which the primary joint pipe communicates and the secondary joint pipe can communicate with each other via a valve port whose opening area is increased or decreased by a needle valve, A valve seat having the valve port is provided between the valve chamber and the secondary joint pipe, and the valve port has a first port on the valve chamber side, a second port having a larger inner diameter than the first port, A motor-operated valve comprising: a first taper portion connecting the first port and the second port;
The valve port includes a third port communicating with the secondary joint pipe, and a second tapered portion connecting the second port and the third port. The inside diameter D1 of the first port and the second port The relationship between the inner diameter D2α of the first port side end, the inner diameter D2β of the third port side end, and the inner diameter D3 of the third port is D1 <D2α <D2β <D3, and the second port Has an opening angle with a taper angle γ, and the angle θ1> θ2> γ with respect to the taper angle θ1 of the first taper portion and the taper angle θ2 of the second taper portion .

  A motor-operated valve according to claim 2 is the motor-operated valve according to claim 1, wherein D2α-D1 ≦ D3-D2β.

  A refrigeration cycle system according to claim 3 is a refrigeration cycle system including a compressor, a condenser, an expansion valve, and an evaporator, wherein the motor-operated valve according to claim 1 or 2 is used as the expansion valve. It is characterized by being used.

  According to the electric valve of the first and second aspects, when the refrigerant flowing from the gap between the first port and the needle valve flows out to the second port, the pressure is not rapidly recovered in the second port, and the flow is reduced. Rectification can stabilize the flow of the refrigerant, and cavitation rupture can be suppressed. Further, when flowing from the second port to the second tapered portion and the third port, the flow velocity is reduced, so that the flow velocity noise can be reduced. Further, when the refrigerant flows from the secondary joint pipe, the gap between the second port and the needle valve is wide because the second port is gently inclined with the taper angle γ satisfying the relationship of θ1> γ. Can be reduced, and noise can be reduced.

  According to the motor-operated valve of the second aspect, since D2α-D1 ≦ D3-D2β, the diameter of the second port is greatly increased from the second tapered portion to the third port. And the flow velocity noise can be further reduced.

  According to the refrigeration cycle system of the fourth aspect, the same effect as that of the first or second aspect can be obtained.

It is a longitudinal section of an electric valve of an embodiment of the present invention. It is an important section enlarged longitudinal section in the vicinity of the valve port in the electric valve of the embodiment of the present invention. It is a figure explaining an operation of a valve port in an electric valve of an embodiment of an embodiment of the present invention. It is a figure showing an example of an air conditioner using an electric valve of an embodiment of the present invention.

  Next, an embodiment of a motor-operated valve according to the present invention will be described with reference to the drawings. FIG. 1 is a vertical sectional view of a motor-operated valve according to an embodiment, FIG. 2 is an enlarged vertical cross-sectional view of a main part in the vicinity of a valve port of the motor-operated valve according to the embodiment, and FIG. FIG. 4 is a diagram showing an example of an air conditioner using the motor-operated valve of the embodiment. Note that the concept of “up and down” in the following description corresponds to the up and down in the drawing of FIG.

  First, an air conditioner according to an embodiment will be described with reference to FIG. The air conditioner includes an electric valve 10 according to an embodiment as an expansion valve, an outdoor heat exchanger 20 mounted on an outdoor unit 100, an indoor heat exchanger 30 mounted on an indoor unit 200, a flow path switching valve 40, and a compressor. 50, each of which is connected as shown by a conduit to form a heat pump type refrigeration cycle system. This refrigeration cycle system is an example of a refrigeration cycle system to which the motor-operated valve of the present invention is applied. The present invention can also be applied to other systems such as a throttle device on the indoor unit side such as a multi air conditioner for a building.

  The flow path of the refrigeration cycle system is switched to two flow paths of a heating mode and a cooling mode by a flow path switching valve 40. In the heating mode, the refrigerant compressed by the compressor 50 flows in the flow path as indicated by a solid arrow. The refrigerant flowing into the indoor heat exchanger 30 from the switching valve 40 and flowing out of the indoor heat exchanger 30 flows into the motor-operated valve 10 through the pipe 60. Then, the refrigerant is expanded by the electric valve 10 and circulated in the order of the outdoor heat exchanger 20, the flow path switching valve 40, and the compressor 50. In the cooling mode, the refrigerant compressed by the compressor 50 flows into the outdoor heat exchanger 20 from the flow path switching valve 40, and the refrigerant flowing out of the outdoor heat exchanger 20 It is expanded, flows through the pipe 60, and flows into the indoor heat exchanger 30. The refrigerant flowing into the indoor heat exchanger 30 flows into the compressor 50 via the flow path switching valve 40. In the example shown in FIG. 4, the refrigerant flows from the primary joint pipe 21 to the secondary joint pipe 22 in the heating mode in the heating mode. Alternatively, the refrigerant may flow from the secondary joint pipe 22 to the primary joint pipe 21.

  The electric valve 10 functions as an expansion valve (throttle device) for controlling the flow rate of the refrigerant. In the heating mode, the outdoor heat exchanger 20 functions as an evaporator, the indoor heat exchanger 30 functions as a condenser, and Heating is done. In the cooling mode, the outdoor heat exchanger 20 functions as a condenser, the indoor heat exchanger 30 functions as an evaporator, and the room is cooled.

  Next, the motor-operated valve 10 according to the embodiment will be described with reference to FIGS. 1 and 2. The electric valve 10 has a valve housing 1 formed by cutting a metal member such as stainless steel or brass or the like, and a valve chamber 1A is formed in the valve housing 1. The motor-operated valve 10 includes a valve seat 1B (a part of the valve housing 1 in this embodiment) below the valve chamber 1A. Further, a first port 11, a second port 12, and a third port 13 are formed in the valve seat 1B. Further, a first tapered portion 14 is formed between the first port 11 and the second port 12, and a second tapered portion 15 is formed between the second port 12 and the third port 13. The first port 11, the first tapered portion 14, the second port 12, the second tapered portion 15, and the third port 13 constitute a "valve port". Further, a primary joint pipe 21 communicating from the side surface to the valve chamber 1A is attached to the valve housing 1, and a secondary joint pipe 22 is attached to one end of the valve chamber 1A in the direction of the axis X. The valve chamber 1 </ b> A and the secondary joint pipe 22 can conduct through the first port 11, the first tapered portion 14, the second port 12, the second tapered portion 15, and the third port 13.

  A valve guide member 23 is attached to the valve housing 1 by press-fitting and caulking so as to be inserted into the valve chamber 1A from above, and a valve guide hole 23a is formed in the center of the valve guide member 23. . A rim 1a is formed at an upper end portion of the valve housing 1 so as to surround an outer peripheral portion of an upper end of the valve guide member 23. The valve housing 1 has a cylindrical case that fits around the outer periphery of the rim 1a. 24 are assembled. The case 24 is fixed to the valve housing 1 by caulking the rim 1a and brazing the outer periphery of the bottom. Further, a support member 3 is attached to an upper end opening of the case 24 via a fixing bracket 31.

  At the center of the support member 3, a female screw portion 3a coaxial with the axis X of the first port 11 and its screw hole are formed, and a cylindrical slide hole 3b having a diameter larger than the outer circumference of the screw hole of the female screw portion 3a. Are formed. In addition, a cylindrical rod-shaped rotor shaft 62 described later is disposed in the screw hole and the slide hole 3a of the female screw portion 3a. A valve holder 4 is fitted into the slide hole 3b so as to be slidable in the direction of the axis X. The valve holder 4 has an upper part connected to the rotor shaft 62 and a lower part holding the needle valve 5. I have.

  The valve holder 4 has a boss 42 fixed to the lower end of a cylindrical portion 41, and a spring receiver 43, a compression coil spring 44, a washer 45, and a spacer 46 in the cylindrical portion 41. The needle valve 5 is formed of a metal member such as stainless steel or brass, and has a substantially elliptical needle portion 5a at the lower end, a rod-shaped rod portion 5b at the lower end, and a flange portion 5c at the upper end. The needle valve 5 is inserted into the insertion hole 42 a of the boss portion 42 of the valve holder 4, and is attached to the valve holder 4 with the flange portion 5 c abutting the boss portion 42. The rod portion 5b of the needle valve 5 is inserted into the valve guide hole 23a of the valve guide member 23.

  In the valve holder 4, the compression coil spring 44 is attached between the spring receiver 43 and the flange portion 5 c of the needle valve 5 while a predetermined load is applied. And the upper end of the cylindrical portion 41 presses the upper end of the spacer 46 via the washer 45. The flange portion 62b of the rotor shaft 62 is engaged between the washer 45 and the spacer 46, and is prevented from falling off by the washer 45. Thus, the needle valve 5 is connected to the rotor shaft 62 via the valve holder 4 and is movable in the axis X direction while being guided by the rod portion 5b.

  A sealed case 25 is hermetically fixed to the upper end of the valve housing 1 by welding or the like. Inside the sealed case 25, there are provided a magnet rotor 61 whose outer peripheral portion is magnetized to have multiple poles, and the rotor shaft 62 fixed to the center of the rotor shaft magnet rotor 61. The upper end of the rotor shaft 62 is rotatably fitted in a cylindrical guide 26 provided on the ceiling of the sealed case 25. Further, a male screw portion 62 a is formed on the rotor shaft 62, and the male screw portion 62 a is screwed with a female screw portion 3 a formed on the support member 3. A stator coil 63 is provided on the outer periphery of the closed case 25, and the magnet rotor 61, the rotor shaft 62 and the stator coil 63 constitute a stepping motor 6. When a pulse signal is given to the stator coil 63, the magnet rotor 61 is rotated according to the pulse number, and the rotor shaft 62 is rotated. A rotation stopper mechanism 27 for the magnet rotor 61 is provided on the outer periphery of the guide 26.

  With the above configuration, the motor-operated valve of the embodiment operates as follows. First, in the valve opening control state in FIG. 1, the driving of the stepping motor 6 rotates the magnet rotor 61 and the rotor shaft 62, and a screw feed mechanism between the male screw portion 62 a of the rotor shaft 62 and the female screw portion 3 a of the support member 3. As a result, the rotor shaft 62 moves in the axis X direction. The needle valve 5 moves in the axis X direction together with the valve holder 4 by the movement of the rotor shaft 62 in the axis X direction accompanying this rotation. The needle valve 5 increases or decreases the opening area of the first port 11 at the needle part 5a, and the refrigerant flowing from the primary joint pipe 21 to the secondary joint pipe 22 or from the secondary joint pipe 22 to the primary joint pipe 21 Is controlled. The case where the refrigerant flows from the primary joint tube 21 to the secondary joint tube 22 is referred to as “first flow”, and the case where the refrigerant flows from the secondary joint tube 22 to the primary joint tube 21 is referred to as “second flow”.

  The first port 11, the second port 12, and the third port 13 have a shape of a side surface of a column centered on the axis X. As shown in FIG. 2, the inner diameter D1 of the first port 11 is the needle portion 5a. The size is adapted to the outer circumference of. The inner diameter D2α of the end of the second port 12 on the first port 11 side is slightly larger than the inner diameter D1 of the first port 11. The inner diameter D3 of the third port 13 is larger than the inner diameter D2β of the end of the second port 12 on the third port 13 side. The inner diameter D4 of the secondary joint pipe 22 is larger than the inner diameter D3 of the third port 13. In FIG. 2, “φ” indicating the diameter is added to each of the diameters D1 to D4. The length L1 of the first port 11 is smaller than the inner diameter D1. Has become. The length L3 of the combination of the second taper portion 15 and the third port 13 is smaller than the length L2 of the combination of the first taper portion 14 and the second port 12.

  Each of the first tapered portion 14 and the second tapered portion 15 has a shape of a frustum of a truncated cone centering on the axis X, and an inner surface of the first tapered portion 14 has an inner diameter from the first port 11 to the second port 12. The inner surface of the second tapered portion 15 has a shape whose inner diameter increases from the second port 12 to the third port 13. The taper angle θ1 which is the opening angle of the first taper portion 14 is larger than the taper angle θ2 which is the opening angle of the second taper portion 15. These dimensions and angles are not limited to those shown in FIG.

  As shown in FIG. 3A, during the first flow, the refrigerant that has passed through the gap between the needle portion 5a and the first port 11 is supplied to the first taper portion 14, the second port 12, and the second taper portion 15. And flows to the secondary joint pipe 22 through the third port 13. At this time, the gap between the needle portion 5a and the first port 11 is the narrowest point, and the flow velocity is maximum here. However, the length L1 of the first port 11 is as short as possible. The flow of the refrigerant flows along the inner wall of the second port 12 immediately following the first tapered portion 14. The inner diameter D2α of the end of the second port 12 on the first port 11 side and the inner diameter D2β of the end of the second port 13 on the side of the third port 13 are only slightly larger than the inner diameter D1 of the first port 11. During the flow to 12, the pressure does not recover rapidly. Since the length of the second port 12 is long, the flow of the refrigerant is rectified at the second port 12. Therefore, the cavitation rupture can be suppressed, and the flow of the refrigerant can be stabilized.

  The refrigerant flowing through the second port 12 flows to the third port 13 while recovering or increasing the pressure following the second taper portion 15. Since the inside diameter D3 of the third port 13 is larger than the inside diameter D2β of the end of the second port 12 on the third port 13 side, the flow velocity is reduced while flowing along the second taper portion 15. That is, the flow velocity is immediately reduced while rectifying to some extent at the second port 12, so that the flow velocity noise is reduced. Further, the flow of the refrigerant decelerated through the second taper portion 15 flows to the third port 13, but the flow of the refrigerant is already rectified in the second port 12, In addition, the flow of the refrigerant is less likely to be disturbed, and the cavitation burst can be suppressed.

  In this manner, by rectifying to some extent at the second port 12 and flowing to the third port 13 via the second tapered portion 15, the flow velocity can be reduced while the rectification is maintained at the second tapered portion 15. . Thereby, the turbulence of the cavitation can be suppressed by reducing the turbulence of the flow in the third port 13, and the flow velocity can be reduced by the second tapered portion 15 to reduce the flow velocity noise.

  On the other hand, as shown in FIG. 3 (B), in the case of the second flow, the refrigerant flowing from the secondary joint pipe 22 passes through the third port 13 and follows the second tapered portion 15 to be in the second port. 12 flows along the inner wall, and further flows to the first port 11 following the first tapered portion 14. Then, it flows into the valve chamber through the gap between the needle portion 5a and the first port 11. Since the second port 12 is gently inclined at the taper angle γ, there is a margin in the gap between the second port 12 and the needle portion 5a, and when the refrigerant flows from the second taper portion 15 to the second port 12 A large differential pressure does not occur, the excitation of the vibration of the needle part 5a can be reduced, and the noise can be reduced. Here, the taper angle γ of the second port 12 has a relationship of θ1> θ2> γ.

  When the pressure difference between the primary joint pipe 21 and the secondary joint pipe 22 is high, the motor-operated valve 10 in the embodiment has a high flow sound reduction effect, and the first port 11, the second port 12, and the third port 11. The dimensions and angles of each part of the port 13, the first tapered portion 14, the second tapered portion 15, and the secondary joint pipe 22 are set so as to satisfy the following conditions.

The conditions of the dimensions and angles of each part of the embodiment in which the effect of reducing the flow velocity noise is high when the pressure difference between the primary joint pipe 21 and the secondary joint pipe 22 is high will be described below. The inner diameter D1 of the first port 11 is
1mm ≦ D1 ≦ 4.5mm
And the inner diameter D2β of the end of the second port 12 on the third port 13 side is:
1.15mm ≦ D2β ≦ 4.9mm
And the inner diameter D3 of the third port 13 is
4.6mm ≦ D3 ≦ 6.35mm
It is.

Further, the taper angle θ1 of the first taper portion 14 is
60 ° ≦ θ1 ≦ 150 °
And the taper angle θ2 of the second taper portion 15 is
30 ° ≦ θ2 ≦ 135 °
Range.

The length L1 of the first port 11 is
0.1mm ≦ L1 ≦ 0.5mm
The noise decreases as the L1 becomes shorter. The length L2 of the first tapered portion 14 and the second port 12 is
0.3mm ≦ L2 ≦ 3mm
And the combination of these lengths L1 and L2 is L1 + L2,
0.4mm ≦ L1 + L2 ≦ 3.5mm
It is set according to the following condition. The sum L1 + L2 + L3 of the length L1 of the first port 11, the length L2 of the first taper portion 14 and the second port 12, and the length L3 of the second taper portion 15 and the third port 13
6mm ≦ L1 + L2 + L3 ≦ 13mm
It is.

The ratio L2 / L1 of the length L2 of the first taper portion 14 and the second port 12 to the length L1 of the first port 11 is as follows:
2 ≦ L2 / L1 ≦ 12
And the ratio L3 / L2 of the length L3 of the second taper portion 15 and the third port 13 and the length L2 of the first taper portion 14 and the second port 12 is:
0.3 ≦ L3 / L2 ≦ 2
And the dimensional ratio D2β / D1 between the inner diameter D2α of the end of the second port 12 on the side of the first axis 11 and the inner diameter D1 of the first port 11 is:
1.05 ≦ D2β / D1 ≦ 2
And the dimensional ratio D3 / D2β of the inner diameter D3 of the third port 13 and the inner diameter D2β of the end of the second port 12 on the axial third port 13 side is:
1.2 ≦ D3 / D2β ≦ 5
Range.

  As described above, the range of each dimension and angle is shown, but the values within this range are values of combinations that satisfy the condition of D1 <D2α <D2β <D3, θ1> γ. Since the second port 12 has an opening angle with a taper angle γ, the relationship between the inner diameters D2α and D2β of the second port 12 is D2α <D2β. The relationship with the inner diameter D1 of the first port 11 can also be appropriately selected from the above conditions.

  In the above embodiment, the valve seat 1B forming the valve port is a part of the valve housing 1 (and a part of the secondary joint 22 '). However, the valve port is formed on another member such as a valve seat member. May be done.

  As described above, the embodiments of the present invention have been described in detail with reference to the drawings. However, the specific configuration is not limited to these embodiments, and a design change or the like may be made without departing from the scope of the present invention. The present invention is also included in the present invention.

1 valve housing 1A valve chamber 1B valve seat 11 first port (part of valve port)
12 2nd port (part of valve port)
13 Third port (part of valve port)
14 1st taper part (part of valve port)
15 Second taper (part of valve port)
21 Primary joint pipe 22 Secondary joint pipe 23 Valve guide member 3 Support member 3a Female screw part 3b Slide hole 4 Valve holder 5 Needle valve 5a Needle part 5b Rod part 6 Stepping motor 61 Magnet rotor 62 Rotor shaft 62a Male screw part 63 Stator coil 4 Valve holder X Axis 13 'Third port 22' Secondary joint tube 22 "Secondary joint tube 15 'Second taper portion 13" Third port 10 Electric valve 20 Outdoor heat exchanger 30 Indoor heat exchanger 40 Flow switching valve 50 compressor

Claims (3)

A motor-operated valve that allows communication between a valve chamber to which a primary joint pipe is communicated and a secondary joint pipe via a valve port whose opening area is increased or decreased by a needle valve, wherein the valve chamber and the secondary joint pipe are connected. And a valve seat having the valve port between the first port and the second port having a larger inner diameter than the first port. A first tapered portion connecting the port and the
The valve port includes a third port communicating with the secondary joint pipe, and a second tapered portion connecting the second port and the third port. The inside diameter D1 of the first port and the second port The relationship between the inner diameter D2α of the first port side end, the inner diameter D2β of the third port side end, and the inner diameter D3 of the third port is D1 <D2α <D2β <D3, and the second port Has an opening angle with a taper angle γ, and the angle θ1>θ2> γ with respect to the taper angle θ1 of the first taper portion and the taper angle θ2 of the second taper portion. . The motor-operated valve according to claim 1, wherein
D2α-D1 ≦ D3-D2β
An electric valve characterized by the following. A refrigeration cycle system including a compressor, a condenser, an expansion valve, and an evaporator, wherein the motor-operated valve according to claim 1 or 2 is used as the expansion valve. Refrigeration cycle system.

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