JP2019152246A - Motor valve - Google Patents

Abstract

To provide a motor valve which obtains large driving force and achieves improvement of sealability between a valve body and a valve seat with a simple mechanism.SOLUTION: A valve body assembly 4 to which multiple (three) valve bodies 41 are assembled is attached to a lower end of a rotor shaft 31. A stepping motor 3 is driven to move the valve body assembly 4 vertically in a valve chamber 1R of a valve housing 1 through a screw feed mechanism formed by a male screw part 31a of the rotor shaft 31 and a female screw part 2a of a support member 2. A valve body seal surface 41a of the valve body 41 is slid relative to valve seat seal surfaces 12a of the multiple valve seats 12 at a side part of the valve chamber 1R to open or close a valve port 121.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a motor-operated valve that controls the flow of fluid, such as switching of a fluid flow path.

  Conventionally, there are various types of switching valves for switching the flow path of the refrigerant pipe in a refrigeration circuit such as an air conditioner or a refrigerator. For example, there are those disclosed in Japanese Patent Application Laid-Open No. 2002-195694 (Patent Document 1) and Japanese Patent Application Laid-Open No. 2010-84939 (Patent Document 2). These switching valves are rotary switching valves that switch a flow path by rotating a main valve with respect to a valve seat in which a valve port is formed. In such a switching valve, normally, the outside of the main valve is high and the inside is low in the valve housing, and the main valve is pressed against the valve seat by this differential pressure to hold the flow path. For this reason, even if the refrigerant flow is stopped, a large torque is required to rotate the main valve when the flow path is switched.

JP 2002-195694 A JP 2010-84939 A

  Patent Document 1 requires a relatively large electric motor in order to obtain a large torque for rotating the main valve, whereas Patent Document 2 has a speed reduction mechanism such as a planetary gear mechanism. Since the electric motor is provided, the electric motor can be reduced in size, but there is a problem that a complicated reduction mechanism such as a planetary gear mechanism is required and the size is increased by the reduction mechanism.

  It is an object of the present invention to provide an electric valve that can obtain a large driving force with a simple mechanism and has a high sealing performance between a valve body and a valve seat.

  The motor-driven valve according to claim 1 has a valve housing having a cylindrical valve chamber, a valve seat having a valve port opening to the valve chamber and having a valve seat seal surface in a plane parallel to the axis of the valve chamber. A valve body having a valve body seal surface that is disposed in the valve chamber and faces the valve seat seal surface, and a support member that supports the rotor shaft of the motor unit on an axis, and the valve body includes the valve body An electric valve which is held by a rotor shaft, moves the valve body in the axial direction via a screw feed mechanism between the rotor shaft and the support member by driving the motor unit, and opens and closes the valve port; A leaf spring for urging the valve body from the axis side toward the valve seat is provided.

  The motor-operated valve according to claim 2 is the motor-operated valve according to claim 1, wherein the valve housing includes a plurality of the valve seats, a plurality of the valve bodies corresponding to the valve seats, and the plurality of the valve bodies. The valve body and the leaf spring are configured as a valve body assembly on the rotor shaft.

  The motor-operated valve according to claim 3 is the motor-operated valve according to claim 2, wherein the plurality of valve bodies are arranged around the axis, and the leaf spring is surrounded by the plurality of valve bodies. It arrange | positions inside the some valve body, It is characterized by the above-mentioned.

  A motor-driven valve according to a fourth aspect is the motor-operated valve according to the second or third aspect, wherein the leaf springs are configured to independently bias the plurality of valve bodies in the direction of the valve seat. It is characterized by that.

  According to the electric valve of the first to fifth aspects, the valve body moves in the direction of the axis L through the screw feed mechanism by driving the motor unit, and the valve body is a leaf spring and the valve seat having the valve port. Since it is biased by the pressure of the fluid, the valve body can be moved with a simple structure, and the valve body seal surface of the valve body can be securely brought into contact with the valve seat seal surface of the valve seat. Can be increased.

  According to the motor-driven valve of claim 2, since the valve body assembly includes a plurality of valve bodies, for example, the valve housing includes a plurality of outlet joint pipes, and a plurality of valves corresponding to the plurality of outlet joint pipes. A plurality of valve bodies can be moved with respect to the seat by a single screw feed mechanism.

  According to the electric valve of the third aspect, the plurality of valve bodies can be urged by one leaf spring.

  According to the motor-driven valve of the fourth aspect, the leaf spring urges the plurality of valve bodies independently in the direction of the valve seat, so that the sealing action of each valve body on the valve seat can be ensured.

It is a longitudinal cross-sectional view of the valve closed state of the motor operated valve of 1st Embodiment of this invention. It is a longitudinal cross-sectional view of the valve open state of the motor operated valve of the first embodiment. It is a figure which shows the relationship between AA arrow sectional drawing and a seal surface of FIG. It is a figure which shows the AA arrow sectional drawing of FIG. 2, and the relationship of a seal surface. It is the disassembled perspective view and assembly perspective view of the valve body assembly in the motor operated valve of 1st Embodiment. It is a figure which shows the modification of the valve body of 1st Embodiment. It is a longitudinal cross-sectional view of the valve closed state of the motor operated valve of the second embodiment.

  Next, an embodiment of the motor-operated valve of the present invention will be described with reference to the drawings. 1 is a longitudinal sectional view of the motor-operated valve according to the first embodiment in a closed state, FIG. 2 is a longitudinal sectional view of the motor-operated valve in an opened state, and FIG. 3 is a sectional view taken along line AA in FIG. FIG. 4 is a cross-sectional view taken along the line AA in FIG. 2 and a diagram showing the relationship between the seal surfaces. Note that the concept of “upper and lower” in the following description corresponds to the upper and lower sides in the drawings of FIGS. 1 and 2. The expressions “clockwise (clockwise)” and “counterclockwise (counterclockwise)” indicate the direction of rotation when the motor-operated valve is viewed from above.

  This electric valve includes a valve housing 1, a support member 2, a stepping motor 3 as a “motor part”, a valve body assembly 4 including a “valve body”, and a sealed case 5.

  The valve housing 1 is formed in a substantially cylindrical shape from a metal such as brass or stainless steel, for example, and has a cylindrical valve chamber 1R having an axis L as a central axis inside thereof. An inlet joint pipe 10 connected to the valve chamber 1R is connected to the lower end of the valve housing 1, and the inner end of the inlet joint pipe 10 on the valve chamber 1R side is an inlet port 10a coaxial with the axis L. Further, three outlet joint pipes 11 are connected to the side portion of the valve housing 1, and a metal such as stainless steel that opens into the valve chamber 1 </ b> R is provided at the end of each outlet joint pipe 11 on the valve chamber 1 </ b> R side. A valve seat 12 made of metal is fitted. The inside of each valve seat 12 serves as a valve port 121 centering on an axis orthogonal to the axis L. Each outlet joint pipe 11 can be electrically connected to the valve chamber 1R via the valve port 121. The end face of the valve seat 12 on the valve chamber 1R side is a valve seat seal surface 12a located in a plane parallel to the axis L that surrounds the outer periphery of the valve port 121, and a valve body is formed on the valve seat seal surface 12a. The valve body seal surface 41a of the valve body 41 in the assembly 4 is in sliding contact. The inlet joint pipe 10 and the outlet joint pipe 11 are fixed to the valve housing 1 by brazing or the like. The material of the valve body 41 is preferably a highly slippery resin such as PPS (polyphenylene sulfide) resin or PTFE (polytetrafluoroethylene) resin to which an additive for improving slidability is added. .

  The support member 2 includes a resin holder portion 21 erected in the center on the stepping motor 3 side, and a fixing bracket 22 integrally formed with a part of the holder portion 21. The fixture 22 is formed by pressing a stainless steel sheet metal, and the lower end is fixed to the upper end of the housing 1 by welding.

  In the center of the support member 2, a female screw portion 2a coaxial with the axis L of the valve chamber 1R and its screw hole are formed, and a cylindrical insertion hole 2b having a diameter larger than the screw hole of the female screw portion 2a is formed. ing. The holder portion 21 of the support member 2 is formed with a guide male screw 21a formed of a spiral protrusion on the outer periphery thereof. Further, a lower end stopper 211 that protrudes radially from the guide male screw 21a is formed at the lower end of the guide male screw 21a (one end of the fixing bracket 22), and protrudes radially at the outer peripheral edge of the upper end portion. An upper end stopper 212 is formed. The guide male screw 21a, the lower end stopper 211, and the upper end stopper 212 are formed integrally with the holder portion 21 of the support member 2. A coil-shaped movable slider 23 is screwed on the outer periphery of the holder portion 21. The movable slider 23 is formed by bending a wire such as a steel material having spring properties, and has a claw portion 23a protruding outward in the radial direction. The female screw portion 2a and the guide male screw 21a are right-hand screws, and the pitch of the guide male screw 21a is set larger than the pitch of the female screw portion 2a.

  The stepping motor 3 is disposed to face the magnet rotor 32 on the outer periphery of the sealed case 5, for example, a rotor shaft 31 made of metal such as stainless steel, a magnet rotor 32 rotatably disposed inside the sealed case 5. The stator coil 33 and other yokes, exterior members, and the like (not shown). The rotor shaft 31 is attached to the center of the magnet rotor 32 by welding the location of the bush 321. A male screw portion 31 a is formed on a part of the outer periphery of the rotor shaft 31. The male screw portion 31 a is screwed into the female screw portion 2 a of the support member 2. Thus, the support member 2 supports the rotor shaft 31 and the magnet rotor 32 on the axis L.

  The valve assembly 4 is disposed in the valve chamber 1R, and includes three valve bodies 41 corresponding to the three valve seats 12, a leaf spring 42, and a binding ring 43. As will be described later, the valve body assembly 4 is held by a flange portion 311 formed integrally with the rotor shaft 31 on the valve chamber 1R side on the axis L. A compression coil spring 6 is disposed between the bundling ring 43 of the valve body assembly 4 and the bottom of the support member 2 in a state where a predetermined load is applied. The bundling ring 43 serves as a spring receiver. Thus, the compression coil spring 6 constantly biases the rotor shaft 31 toward the inlet joint pipe 10. As the material of the binding ring 43, like the above-described valve body 41, high slipperiness such as PPS (polyphenylene sulfide) resin or PTFE (polytetrafluoroethylene) resin to which an additive for improving slidability is added. A resin is preferred.

  The sealed case 5 is formed in a substantially cylindrical shape whose upper end is closed, and is hermetically fixed to the upper end of the valve housing 1 through a lid member 51 by welding. A dimple 52 for positioning and fixing a stator unit (not shown) in which the stator coil 33 of the stepping motor 3 is housed is formed at the lower part of the outer periphery of the sealed case 5.

  With the above configuration, the magnet rotor 32 and the rotor shaft 31 are rotated by the driving of the stepping motor 3, and the rotor shaft 31 and the valve are rotated by the screw feed mechanism between the male screw portion 31a of the rotor shaft 31 and the female screw portion 2a of the support member 2. The body assembly 4 moves in the direction of the axis L. That is, the valve body assembly 4 moves up and down on the axis L according to the rotation direction of the magnet rotor 32. As a result, the valve port 121 of the valve seat 12 opposed to the valve body 41 of the valve body assembly 4 is opened and closed, and the valve opened state in which the fluid flowing in from the inlet joint pipe 10 flows out to the outlet joint pipe 11, and the outlet joint pipe 11 is controlled to switch to a valve closed state that blocks the outflow to 11. Further, the flow rate of the fluid flowing through the valve port 121 can be controlled according to the position (lift amount) of the valve body 41 in the axis L direction with respect to the valve port 121. Further, in order to switch the open state of the valve port 121, the valve body seal surface 41a or the slide shaft 412 and the valve seat seal surface 12a are in contact with each other on a flat surface after the opening degree is increased. For this reason, the valve element 41 does not rotate regardless of the rotation of the magnet rotor 32. Thereby, rotation of the valve body assembly 4 is prevented, and the opening degree of the valve port 121 is made variable by only moving in the direction of the axis L. Furthermore, since the flat surfaces are brought into contact with each other, the sealing performance at a necessary portion is improved, and highly accurate flow rate control is possible.

  A protrusion 32 a parallel to the axis L is formed on a part of the inner peripheral surface of the magnet rotor 32, and this protrusion 32 a contacts the claw portion 23 a of the movable slider 23 when the magnet rotor 32 rotates. Then, the movable slider 23 is rotated so as to be rotated in the same direction. Accordingly, the movable slider 23 moves following the guide male screw 21a, and the claw portion 23a of the movable slider 23 is moved to the lower end at the position of the valve body assembly 4 where the valve port 121 is fully closed as shown in FIG. The rotation stops upon contact with the stopper 211. Further, when the magnet rotor 32 and the rotor shaft 31 are raised counterclockwise, the movable slider 23 finally comes into contact with the upper end stopper 212 as shown in FIG.

  5A is an exploded perspective view of the valve body assembly 4, and FIG. 5B is an assembled perspective view of the valve body assembly 4. FIG. In the valve body assembly 4, the three valve bodies 41 have the same shape, and each valve body 41 is assembled at a position spaced 120 ° around the axis L. The valve body 41 has a boss 411 at the upper part on the rotor shaft 31 side, and a pair of parallel slide shafts 412 at the lower part on the inlet joint pipe 10 side. And in the valve body 41, the surface by the side of the valve seat 12 between the boss | hub part 411 and the slide shaft 412 is the planar valve body sealing surface 41a.

  An opening 41 b that matches the diameter of the valve port 121 is formed between the pair of slide shafts 412. Further, a spring accommodating portion 41c in which the spring piece 42a of the leaf spring 42 is disposed is formed on the back side (axis L side) of the valve body sealing surface 41a of the valve body 41, and an engagement groove is formed on the back side of the boss portion 411. 41d is formed. The leaf spring 42 is formed of an elastic plate, and includes three spring pieces 42a corresponding to the valve bodies 41 at positions separated by 120 ° around the axis L. And this spring piece 42a presses the back side of the valve body sealing surface 41a of the valve body 41, ie, the inner wall of the spring accommodating part 41c. Further, on the flange portion 311 of the rotor shaft 31, for example, a highly slippery resin such as PPS (polyphenylene sulfide) resin or PTFE (polytetrafluoroethylene) resin to which an additive for improving slidability is added is used. A washer 312 is provided.

  With the above configuration, each valve body 41 is assembled by disposing the leaf spring 42 in the spring accommodating portion 41 c and engaging the engaging groove 41 d with the flange portion 311 and the washer 312 from the outer periphery. Further, the binding ring 43 is fitted into the boss portion 411 of each valve body 41, and the binding ring 43 is brought into contact with the base portion 411 a of the boss portion 411 by the compression coil spring 6. That is, the urging force of the compression coil spring 6 urges the valve body 41 toward the inlet joint pipe 10 via the binding ring 43, and the washer 312 is formed by the inner top portion of the engagement groove 41 d and the flange portion 311 of the rotor shaft 31. Each valve element 41 is assembled with respect to the rotor shaft 31 in a state where is interposed. The washer 312 is formed of a member that reduces friction between the valve body 41 and the flange portion 311, and reduces the transmission of the rotational force of the rotor shaft 31 to the valve body assembly 4.

  Here, as shown in FIGS. 3 and 4, there is a gap between the three valve bodies 41, and the valve bodies 41 are arranged at positions that do not interfere with each other. The binding ring 32 is fitted in the boss portion 411 of each valve body 41. The binding ring 32 transmits a force to the valve body 41 in the direction of the axis L, but in the inner diameter direction with respect to the axis L. The position of the valve body 41 is not restricted. Therefore, the leaf spring 42 urges each valve element 41 to the valve seat 12 side independently by each spring piece 42a. Moreover, since the pressure of the fluid flowing in from the inlet joint pipe 10 acts on the inside of each valve body 41, the pressure of this fluid also urges the valve body 41 toward the valve seat 12 in cooperation with the leaf spring 42.

  As described above, the valve body assembly 4 is attached to the lower end of the rotor shaft 31, whereby the valve body 41 is held on the rotor shaft 31. Then, the valve element 41 is moved in the direction of the axis L through the screw feed mechanism by driving the stepping motor 3 as the “motor unit”, and the flow of the fluid flowing through the valve port 121 is controlled by opening and closing the valve port 121. Can do. Further, since the valve body 41 is urged toward the valve seat 12 by the urging force of the leaf spring 42 (spring piece 42 a) and the pressure of the fluid, the valve of the valve body 41 against the valve seat seal surface 12 a of the valve seat 12. The body seal surface 41a can be brought into contact with each other reliably, and the sealing performance can be improved.

  Further, since the valve element 41 is in sliding contact with the pair of slide shafts 412 on the valve seat seal surface 12a of the valve seat 12 even when the valve is open, the valve element 41 is prevented from rotating even when the lift amount is large. be able to. Furthermore, since the slide shaft 412 is on the valve seat seal surface 12a even when the valve is closed, the valve body seal surface 41a of the valve body 41 can be smoothly moved onto the valve seat seal surface 12a. .

  FIG. 6 is a view showing a modified example of the valve body 41 of the first embodiment. In this modified example and the second embodiment described later, the same elements as those of the first embodiment have the same operational effects. The same members in the drawings of the modified example and the second embodiment are denoted by the same reference numerals as those in FIGS. The valve body 41 of this modification is formed by forming a wedge-shaped orifice groove 41A that communicates with the opening 41b on the valve body seal surface 41a. Also in the first embodiment, by controlling the position of the valve body 41 with respect to the valve seat seal surface 12a (and the valve port 121), it is possible to control the flow rate of the fluid flowing to the valve port 121, but in this modification, The flow rate can be further controlled by the orifice groove 41A.

  FIG. 7 is a longitudinal sectional view of the motor-operated valve according to the second embodiment of the present invention in a closed state. The second embodiment differs from the first embodiment in one valve body 41 ′ and outlet joint pipe 11 ′ in the valve body assembly 4 ′. In the second embodiment, in addition to the three outlet joint pipes 11 similar to those in the first embodiment, an outlet joint 11 ′ arranged in parallel with one outlet joint pipe 11 is provided. One valve body 41 'in the valve body assembly 4' is provided corresponding to the parallel outlet joint pipe 11 and outlet joint pipe 11 '. The valve body 41 'has a valve body seal surface 41a similar to the first embodiment corresponding to the outlet joint pipe 11' and the valve seat 12 ', an opening 41b, and a pair of slide shafts 412 at the lower part. Yes. Further, a valve body seal surface 41 a ′ corresponding to the outlet joint pipe 11 is provided between the valve body seal surface 41 a and the boss portion 411. The valve body seal surface 41 a ′ in the second embodiment is configured to form a gap between the valve seat seal surface 12 a of the valve seat 12.

  And in this 2nd Embodiment, when the valve body assembly 4 'exists in the position (state of FIG. 6) similar to the valve body assembly 4 in FIG. 1 of 1st Embodiment, the valve body sealing surface of valve body 4'. 41a closes the valve port 121 'of the valve seat 12', and the valve body seal surface 41a 'slightly opens the valve port 121 of the valve seat 12. On the other hand, when the valve body assembly 4 'is in the same position as the valve body assembly 4 of FIG. 2 of the first embodiment, the valve body seal surface 41a of the valve body 41' is the valve seat seal surface 12a 'of the valve seat 12'. Away from the valve port 121 ′ opens. At this time, the valve body seal surface 41a of the valve body 41 'comes into contact with the valve seat seal surface 12a of the upper valve seat 12 so that the valve is closed. Further, the flow rate of the fluid flowing through the valve ports 121 and 121 'can be controlled according to the position (lift amount) of the valve body assembly 4' in the axis L direction, and the flow rates of the outlet joint pipes 11 and 11 'can be different. Control can be performed.

  The motor-operated valve of each of the above embodiments (and modifications) can be used as one that controls the flow of the refrigerant as follows. For example, to a plurality of refrigerant flow paths (paths) provided independently in the evaporator in order to effectively operate the evaporator in a refrigeration cycle system including a compressor, a condenser, an expansion device, an evaporator, etc. The distribution of the refrigerant can be controlled. In this case, the motor-operated valve according to the embodiment is provided as a flow divider (variable flow divider) for controlling the distribution of the refrigerant between the expansion device and the evaporator. That is, by connecting the inlet joint pipe 10 of the motor-operated valve of the embodiment to a throttle device and connecting the three outlet joint pipes 11 to the refrigerant flow paths of the evaporator, It is possible to control supply and stop of the refrigerant to each refrigerant flow path, control the flow rate of the refrigerant, and the like. Moreover, in the motor operated valve according to the second embodiment, the refrigerant can be controlled for each of a plurality of independent flow paths by controlling the flow and flow rate of the fluid to the three outlet joint pipes 11 to be different. For example, it is possible to control the flow rate of the refrigerant at this time by allowing the refrigerant to flow through only a specific one of the plurality of independent refrigerant channels of the evaporator. Thereby, the optimal control according to the site | part of the evaporator corresponding to a some independent refrigerant | coolant flow path is attained. In addition, when controlling a plurality of refrigeration cases (showcases), the motor-operated valve of each embodiment (and modification) can be connected to a plurality of evaporators. In this case, the motor-operated valve of the embodiment is provided between the expansion device and the plurality of evaporators on the downstream side. That is, the inlet joint pipe 10 of the motor-operated valve of the embodiment is connected to a throttling device, the three outlet joint pipes 11 are connected to the respective evaporators, and the supply and stop of the refrigerant are controlled, or the flow rate control of the refrigerant By doing so, the ability of the three evaporators can be controlled according to the operating conditions.

  In the first embodiment, the valve body 41 having the opening 41b having the same shape is used. However, the present invention is not limited to this, and the valve body 41 corresponding to each valve port 121 is different, for example, by changing the shape of the opening 41b. By varying the shape, the flow and flow rate of the fluid to the outlet joint pipe 11 according to the lift amount of the valve assembly 4 may be varied. Thereby, a refrigerant | coolant can be controlled by various patterns.

  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 the design can be changed without departing from the scope of the present invention. Is included in the present invention.

DESCRIPTION OF SYMBOLS 1 Valve housing 1R Valve chamber L Axis 10 Inlet joint pipe 10a Inlet port 11 Outlet joint pipe 12 Valve seat 12a Valve seat sealing surface 121 Valve port 2 Support member 2a Female thread part 21 Holder part 22 Fixing bracket 3 Stepping motor (motor part)
31 Rotor shaft 31a Male thread portion 311 Flange portion 312 Washer 32 Magnet rotor 33 Stator coil 4 Valve body assembly 41 Valve body 41a Valve body seal surface 41b Opening portion 41c Spring accommodating portion 41d Engaging groove 411 Boss portion 412 Slide shaft 41A Orifice groove 42 Leaf spring 42a Spring piece 43 Binding ring 5 Sealing case 6 Compression coil spring 11 'Outlet joint pipe 12' Valve seat 12a 'Valve seat seal surface 121' Valve port 4 'Valve body assembly 41' Valve body 41a 'Valve body seal surface 100 Electric Valve 200 Outdoor heat exchanger 310 First indoor heat exchanger 320 Second indoor heat exchanger 400 Four-way valve 500 Compressor 600 Expansion valve

Claims (4)

A valve housing having a cylindrical valve chamber, a valve seat having a valve port opening in the valve chamber and having a valve seat seal surface in a plane parallel to the axis of the valve chamber, and disposed in the valve chamber. A valve body having a valve body seal surface facing the valve seat seal surface, and a support member for supporting the rotor shaft of the motor unit on an axis,
The valve body is held by the rotor shaft, and the motor is driven to move the valve body in the axial direction via a screw feed mechanism between the rotor shaft and the support member to open and close the valve port. A valve,
A motor-operated valve comprising a leaf spring that biases the valve body from the axis side toward the valve seat.   The valve housing includes a plurality of the valve seats, a plurality of the valve bodies corresponding to the valve seats, and the valve bodies and the leaf springs are configured as valve body assemblies on the rotor shaft. The motor-operated valve according to claim 1, wherein:   The plurality of valve bodies are disposed around the axis, and the leaf spring is disposed inside the plurality of valve bodies so as to be surrounded by the plurality of valve bodies. The motorized valve described.   The motor-operated valve according to claim 2 or 3, wherein the leaf spring is configured to urge the plurality of valve bodies independently in the direction of the valve seat.

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