JP2019032085A - Motor valve - Google Patents

Abstract

To provide a motor valve which reduces variations in valve opening points to secure fine controllability without being affected by assembly accuracy and accuracy of used components.SOLUTION: A support member 2 is press-fitted into a valve housing 1 to be attached thereto and a fixed side stopper member 4 is attached to the support member 2 to form a body assembly 10. A magnet rotor 62 is fixed to a valve rod 3 (a rotor shaft) to which a biasing spring 5 is attached by a fixing member 7 to form a valve body assembly 20. The valve body assembly 20 and the fixed side stopper member 4 threadedly engage with a male screw part 21a of the support member 2. In a setting process during assembly, the valve body assembly 20 is rotated and a position, at which a flow rate of air flowing through a valve port 13 becomes a predetermined value, is set to a setting opening. In a state where a stopper contact part 4b of the fixed side stopper member 4 and a movable side stopper 62a of the magnet rotor 62 contact with each other, the fixed side stopper member 4 is joined (fixed) to the support member 2.SELECTED DRAWING: Figure 1

Description

  The present invention relates to an electric valve that controls a flow rate of a fluid such as a refrigerant such as an expansion valve of a refrigeration circuit such as an air conditioner or a refrigerator.

  Conventionally, as an electric valve used in a refrigeration circuit such as an air conditioner or a refrigerator, for example, flow control disclosed in Japanese Patent Application Laid-Open No. 2013-204613 (Patent Document 1) and Japanese Patent No. 5697909 (Patent Document 2). There is a valve. This flow control valve (electric valve) has a magnet rotor disposed in a case of a stepping motor (electric motor), and has a needle part (valve element part) in the lower part at the center of a male screw shaft fixed to the magnet rotor. The valve body is inserted. The male screw shaft forms a screw feed mechanism together with the female screw of the support member on the valve body side.

  And it is comprised so that a magnet rotor may be rotated and a valve port may be opened and closed by a needle part with a screw feed mechanism. Moreover, in the thing of patent document 1, the rotation range of a magnet rotor is regulated by the fixed lower end stopper of the upper end of a support member, and the movable lower end stopper of the magnet rotor side. Moreover, in the thing of patent document 2, a stopper mechanism is comprised by combining a guide bush and a fully-closed stopper, and when a fully-closed stopper contacts the lower step part of a guide bush, a magnet rotor (and valve | bulb) is comprised. The lower end position of the body part is set.

JP 2013-204613 A Japanese Patent No. 5697909

  In recent years, improvement in energy saving performance has been actively studied for air conditioners and refrigerators, and the same performance is required for motor-operated valves used in the refrigeration circuit. Examples of the performance required for the motor-operated valve include an improvement in controllability in a minute flow rate range and a reduction in flow rate variation.

  In particular, in a large air conditioner (PAC, building multi, etc.), there are applications in which the motor-operated valve must be closed. In this case, the motor-operated valve must be opened with a predetermined pulse (valve-opening point) from the valve-closed state. However, the valve-opening point may vary greatly depending on the assembly accuracy of the motor-operated valve and the accuracy of parts used. When an air conditioner is operated for the purpose of improving energy saving, there is no choice but to deal with this variation by controlling the compressor and the fan. When the valve opening points vary greatly, the flow rate at the specified valve opening also varies greatly, and it is considered that fine controllability is impaired. Eliminating such variations is a very important issue particularly when performing control in a minute flow rate range in an air conditioner, and is also a major issue for an electric valve used in an air conditioner.

  It is an object of the present invention to ensure fine controllability in a motor-operated valve by reducing variations in valve opening points without being affected by assembly accuracy and accuracy of parts used.

  The motor-operated valve according to claim 1 is formed on the support member, a support member disposed on the opposite side to the valve port with respect to the valve chamber having the valve port and having a male thread portion formed coaxially with the axis of the valve port. A rotor shaft that is inserted through the valve guide hole and has a valve body portion on the valve port side, and a female screw portion that is screwed into the male screw portion of the support member, and the rotor shaft And a stopper mechanism for regulating a lower end position of the magnet rotor with respect to the support member. The magnet rotor is rotated by the electric motor, and the magnet rotor An electric valve that controls the flow rate of fluid passing through the valve port by moving the valve body portion forward and backward with respect to the valve port by a screw feed mechanism between the female screw portion and the male screw portion of the support member. The stopper mechanism is provided on the magnet rotor side, and a fixed stopper member that is screwed into the male screw portion of the support member, is rotatable about the axis, and is movable in the axial direction. And a movable stopper that is capable of abutting at a lower end position of the magnet rotor at a stopper abutting portion that protrudes at one location on the circumference of the stationary stopper member, and the stationary stopper member is supported by the supporting stopper member. It is joined to the support member at an intermediate position of the male screw portion of the member, the intermediate position is a position corresponding to a predetermined valve opening set in the electric valve, and the magnet rotor is connected to the male screw. A rotor main body made of PPS resin in which the female thread portion to be screwed to the portion is formed, and a magnet having an outer peripheral portion magnetized in multiple poles.

  According to the electric valve of the first aspect, the fixed-side stopper member has its stopper abutting portion abutting on the movable-side stopper of the magnet rotor to stop the magnet rotor and the valve body portion at the lower end position, thereby opening the predetermined valve. Degree is obtained. Further, since the fixed-side stopper member is joined at an intermediate position of the male screw portion of the support member, the fixed-side stopper member is movable in the axial direction before this joining. Therefore, this fixed-side stopper member can be fixed at a position where the valve is opened from the valve closed state by the set opening, and the setting of the valve opening is facilitated. Since the valve opening is set only by the position of the fixed stopper member in the axial direction, the valve opening can be set without being affected by the accuracy of the parts.

It is a longitudinal cross-sectional view of the motor operated valve manufactured by the manufacturing method of one Embodiment of this invention. It is a figure which shows the assembly process of the main body assembly in the manufacturing method of the motor operated valve of embodiment. It is a figure which shows the assembly process of the valve body assembly in the manufacturing method of the motor operated valve of embodiment. It is a figure which shows the mounting process which mounts the main body assembly to the valve body assembly in the manufacturing method of the electrically operated valve of embodiment. It is a figure which shows the valve closing process in the manufacturing method of the electrically operated valve of embodiment, and the setting process of an open specification valve. It is a figure which shows the assembly | attachment process of the case in the manufacturing method of the motor operated valve of embodiment. It is a figure which shows the setting process of the open specification valve in the manufacturing method of the motor operated valve of embodiment. It is a figure which shows the modification of the movable side stopper in embodiment.

  Next, an embodiment of a motor-operated valve and a method for manufacturing the same according to the present invention will be described with reference to the drawings. FIG. 1 is a longitudinal sectional view of an electric valve according to an embodiment manufactured by the manufacturing method of the embodiment. Note that the concept of “upper and lower” in the following description corresponds to the upper and lower sides in the drawing of FIG. The expressions “clockwise (clockwise)” and “counterclockwise (counterclockwise)” indicate the direction of rotation when the motor-operated valve is viewed from above.

  This electric valve has a valve housing 1 formed by cutting a metal member with stainless steel, brass, or the like, and the valve housing 1 has a valve chamber 1A inside thereof. A first joint pipe 11 connected to the valve chamber 1 </ b> A is connected to one outer peripheral side of the valve housing 1. A second joint pipe 12 is connected to the lower end of the valve housing 1, and a valve port 13 is formed on the inner bottom surface of the valve housing 1. The second joint pipe 12 is connected to the valve port 13 via the valve port 13. Conducted to chamber 1A. The first joint pipe 11 and the second joint pipe 12 are fixed to the valve housing 1 by brazing or the like. An attachment hole 14 that opens to the upper end is formed on the opposite side of the valve housing 1 from the valve port 13, and the support member 2 is attached to the attachment hole 14 by press-fitting.

  The support member 2 has a substantially cylindrical holder portion 21 and a flange portion 22 formed near the valve housing 1 of the holder portion 21. A male screw portion 21a is formed on the outer periphery of the holder portion 21 of the support member 2 from a substantially middle portion to the flange portion 22, and a cylindrical rotor for guiding a magnet rotor 62 described later is provided above the male screw portion 21a. A guide 21b is formed. Further, a valve guide hole 21c coaxial with the axis L of the valve port 13 is formed at the center of the support member 2, and the valve rod 3 as a “rotor shaft” is inserted into the guide hole 21c. A fixed-side stopper member 4 is disposed on the holder portion 21 of the support member 2.

  The valve rod 3 is made of stainless steel or the like, and has a needle portion 31 as a “valve body portion” at the lower end, a cylindrical portion 32 inserted into the guide hole 21 c of the support member 2, and a rod-shaped rod having a smaller diameter than the cylindrical portion 32. Part 33. A biasing spring 5 is disposed around the rod portion 33 between the step portion 32a of the cylindrical portion 32 and the magnet rotor 62 in a compressed state. Thereby, the valve stem 3 is always urged toward the valve port 13 with respect to the magnet rotor 62.

  The fixed-side stopper member 4 has a donut-like shape, and a female screw portion 4a coaxial with the axis L of the valve port 13 is formed inside thereof. In addition, a stopper abutting portion 4b that protrudes toward the magnet rotor 62 is formed at one place on the circumference around the axis L of the fixed-side stopper member 4. The fixed-side stopper member 4 has a female threaded portion 4a screwed into a male threaded portion 21a on the support member 2 side and a gap G between the flanged portion 22 and the support member 2 by welding or the like. Joined (fixed). That is, the fixed side stopper member 4 is joined to the middle position of the male screw portion 21a due to the gap G. The “intermediate position” may be any position in the direction of the axis L with respect to the male screw portion 21a as long as the gap G is formed, and this position is determined according to the valve opening to be set.

  A lid 15 is attached to the upper end of the valve housing 1, and a case 61 of a stepping motor 6 as an “electric motor” is airtightly fixed to the lid 15 by welding or the like. In the case 61, a magnet rotor 62 whose outer peripheral portion is magnetized in multiple poles is rotatably provided. A stator coil 63 is disposed on the outer periphery of the case 61. The stepping motor 6 rotates the magnet rotor 62 according to the number of pulses when a pulse signal is given to the stator coil 63.

  The magnet rotor 62 is composed of a rotor body 621 and a magnet 622 fixed to the outer periphery thereof. The rotor body 621 is made of a PPS resin to which an additive for improving slidability is added, but this may be a metal such as SUS or brass. The magnet 622 is molded by mixing magnetic powder into a base material made of PPS or the like. The magnet 622 may be a permanent magnet made of ferrite.

  A female screw portion 621a coaxial with the axis L of the valve port 13 and a screw hole thereof are formed below the center of the rotor main body 621, and at the center of the rotor main body 621 from the inner periphery of the screw hole of the female screw portion 621a. A cylindrical slide hole 621b having a small diameter is also formed. Further, a valve rod insertion hole 621c is formed at the upper center of the slide hole 621b. In addition, a movable side stopper 62a protruding downward is formed at one lower portion of the magnet 622.

  The valve stem 3 is inserted into the guide hole 21 c of the support member 2, and the end 3 a of the valve stem 3 (the end of the rod portion 33) is inserted into the valve rod insertion hole 621 c of the rotor body 621. The magnet rotor 62 is inserted into the slide hole 621b through the rotor guide 21b of the support member 2, and the female screw portion 621a on the magnet rotor 62 side is screwed to the male screw portion 21a on the support member 2 side. . A fixing member 7 is press-fitted into the end 3a of the valve stem 3, and the fixing member 7 is fixed integrally with the valve stem 3 by welding.

  The male screw portion 21a and the female screw portion 621a are screw feeding mechanisms. In this embodiment, the male screw portion 21a and the female screw portion 621a are right-hand screws. A compression spring 64 is provided between the case 61 and the magnet rotor 62 to urge the magnet rotor 62 in the valve closing direction. However, backlash between the male screw portion 21a and the female screw portion 621a occurs. By removing, it acts to reduce the operating sound of the magnet rotor 62.

  With the above configuration, when the magnet rotor 62 rotates, the magnet rotor 62 moves in the direction of the axis L (up and down) by the screw feeding action of the female screw portion 621a and the male screw portion 21a. When the needle portion 31 is not seated on the valve port 13, the urging force of the urging spring 5 brings the fixing member 7 into contact with the magnet rotor 62, and the valve stem 3 moves together with the magnet rotor 62. The needle portion 31 advances and retreats with respect to the valve port 13. Thereby, the opening degree of the valve port 13 is changed, and the flow rate of the refrigerant flowing from the first joint pipe 11 to the second joint pipe 12 or the flow rate of the refrigerant flowing from the second joint pipe 12 to the first joint pipe 11 is controlled. The

  When the needle portion 31 is in the control range for controlling the flow rate and the magnet rotor 62 rotates and descends, the movable side stopper 62a passes over the stopper contact portion 4b of the fixed side stopper member 4. Further, when the magnet rotor 62 rotates and descends and the movable stopper 62a contacts the stopper contact portion 4b of the fixed stopper member 4, the rotation is restricted. That is, the movable stopper 62 a and the stopper contact portion 4 b of the fixed stopper member 4 constitute a stopper mechanism that regulates the lower end position of the magnet rotor 62. As described above, the instantaneous position at which the rotation of the magnet rotor 62 is stopped by the stopper mechanism and the movable stopper 62a comes into contact with the stopper contact portion 4b of the fixed stopper member 4 is referred to as “rotor starting point”.

  Here, the electric valve of the embodiment can be set to the following two specifications. First, when the magnet rotor 62 rotates clockwise and the movable stopper 62a contacts the stopper contact portion 4b of the fixed stopper member 4, that is, at the "rotor starting point", the needle portion 31 closes the valve port 13. There is no specification, this is called "open specification valve". Secondly, a specification in which the needle portion 31 closes the valve port 13 and the urging spring 5 is further compressed at the “rotor starting point”, which is called a “closed specification valve”. Of course, the valve can be closed just at the “rotor starting point”.

  2 to 7 are views showing a method and a manufacturing process of the motor-operated valve according to the embodiment. 2 to 7, the reference numerals are given only to the main members, and the reference numerals of the other members are omitted. In addition, a part of the oblique lines indicating the cross section is omitted, and parts related to the operation and assembled parts are indicated by oblique lines in each process.

  First, as shown in FIG. 2A, the support member 2 is press-fitted into the mounting hole 14 of the valve housing 1 to which the first joint pipe 11, the second joint pipe 12 and the lid 15 are attached. The support member 2 is attached to the. Next, as shown in FIG. 2B, the fixed-side stopper member 4 is screwed to an appropriate position with respect to the male screw portion 21 a of the holder portion 21 of the support member 2. As a result, the main assembly 10 shown in FIG.

  On the other hand, as shown in FIG. 3 (A), a magnet rotor 62 and a fixing member 7 are attached to the rod portion 33 of the valve stem 3 to which the biasing spring 4 is attached, and fixed as shown in FIG. 3 (B). The member 7 is joined to the end 3a of the valve stem 3 by welding, press fitting, or the like. Thus, the valve body assembly 20 is obtained by integrating the magnet rotor 62 and the valve stem 3.

  Next, as shown in FIG. 4A, the valve body assembly 20 is attached to the main assembly 10. That is, the female screw portion 621a of the magnet rotor 62 is screwed into the male screw portion 21a of the support member 2, and the valve body assembly 20 is rotated clockwise. This clockwise direction is the “first rotation direction”. As a result, as shown in FIG. 4B, the movable stopper 62 a of the magnet rotor 62 is brought into contact with the stopper contact portion 4 b of the fixed stopper member 4.

  Next, for example, a flow meter (or pressure gauge) is installed on the first joint pipe 11 side, and the first joint pipe is connected from the second joint pipe 12 through the valve port 13 as shown in FIG. 11, the valve body assembly 20 is rotated clockwise while the movable stopper 62a is in contact with the stopper contact portion 4b. Then, when the flow rate (or pressure) of the air flowing out from the first joint pipe 11 becomes 0, the needle portion 31 of the valve rod 3 is seated on the valve port 13, that is, the valve is closed. Next, as shown in FIG. 5 (B), while the air (fluid) flows from the second joint pipe 12 to the first joint pipe 11 via the valve port 13, the stationary stopper member 4 is turned counterclockwise. This counterclockwise direction is the “second rotational direction”. At this time, since the fixed-side stopper member 4 is in contact with the movable stopper 62a of the magnet rotor 62, the valve body assembly 20 also follows and the needle portion 31 rises from the valve port 13 and the valve starts to open.

  Then, when the flow rate (or pressure) of the air flowing out from the first joint pipe 11 reaches a predetermined set value, the valve body assembly 20 and the fixed-side stopper member 4 are stopped, and as shown in FIG. Then, the fixed-side stopper member 4 is joined to the support member 2 by welding or the like. Thereby, the valve opening degree at the lowermost position where the movable stopper 62a of the magnet rotor 62 abuts against the fixed-side stopper member 4 can be set. This setting is a setting of “open specification valve”. The fixing side stopper member 4 may be joined in any direction as long as it is a method of joining to the support member 2 such as welding or adhesion.

  When the joining of the fixed side stopper member 4 is completed, as shown in FIG. 6, a compression spring 64 is disposed on the upper part of the valve body assembly 20 to cover the case 61, and the case 61 and the valve housing 1 are connected by welding or the like. Join. Thereby, the motor-operated valve shown in FIG. 1 is completed.

  In the above example, a flow meter (or pressure gauge) is installed on the first joint pipe 11 side so that fluid (for example, air) flows from the second joint pipe 12, but on the second joint pipe 12 side. A flow meter (or pressure gauge) may be installed so that a fluid (for example, air) flows from the first joint pipe 11. In addition, the state in which the needle portion 31 is seated on the valve port 13, that is, the valve closed state, is detected by the flow rate and the pressure being 0. For example, the valve rod 3 and the valve port 13 (valve housing 1) The valve closed state may be detected by detecting the electrical conduction state between them, or other methods may be used.

  In the above example, the example in which the stationary stopper member 4 is rotated together with the valve body assembly 20 until the air flow rate (or pressure) reaches a predetermined set value has been described. Only the valve body assembly 20 is rotated until the air flow rate (or pressure) reaches a predetermined set value, and after reaching the predetermined set value, the valve body assembly 20 is fixed to the valve housing 1 in a fixed state. The side stopper member 4 is rotated. The fixed stopper member 4 may be joined to the support member 2 by welding or the like at a position where the stopper contact portion 4b of the fixed stopper member 4 contacts the movable stopper 62a.

  Next, the “closed specification valve” is set as follows. First, the valve body assembly 20 is rotated clockwise (rotated in the first rotation direction) in the same manner as described above until the valve is closed. When the valve is closed, the fixed side stopper 4 is further rotated clockwise as shown in FIG. 7A with reference to the rotation position, and rotated by a predetermined rotation amount as shown in FIG. 7B. At this position, the fixed-side stopper member 4 is joined to the support member 2 by welding or the like. 7B shows a state in which the fixed stopper member 4 is joined to the support member 2 and the valve assembly 20 is rotated clockwise so that the movable stopper 62a is the stopper contact portion 4b of the fixed stopper member 4. FIG. The state which contact | abutted to is shown. Further, when the valve body assembly 20 is rotated clockwise from the valve closed state, a gap is formed between the fixing member 7 and the rotor body 621 of the magnet rotor 62 in the valve body assembly 20.

  In the above example, the case where the fixed-side stopper 4 is rotated by a predetermined rotation amount has been described. However, when the fixed-side stopper 4 is rotated by a predetermined rotation amount, the valve body assembly 20 is rotated to rotate the valve body assembly. The stationary stopper 4 may be rotated by following the movement 20.

  As described above, when the “open specification valve” is set, the fixed-side stopper member 4 is rotated while the fixed-side stopper member 4 is in contact with the magnet rotor 62 of the valve body assembly 20, and the valve port 13 is rotated. The positions of the fixed-side stopper member 4 and the valve body assembly 20 are set when the flow rate of the fluid flowing through becomes a set flow rate. When the “closed specification valve” is set, the position of the fixed stopper member 4 is set by rotating the fixed stopper 4 (or the valve body assembly 20) by a predetermined amount of rotation from the valve closed state. Therefore, the dependence on the component accuracy can be reduced and the valve opening can be adjusted accurately. In addition, since component accuracy can be made rough, component costs can be reduced.

  In the setting process of the “open specification valve”, since the valve is closed by the valve closing process and then adjusted in the valve opening direction, a minute valve opening can be quickly set. It is also possible to set the valve opening degree by adjusting from a certain valve open state to the valve closing direction.

  In the above embodiment, the movable-side stopper 62a on the magnet rotor 62 side is formed below the magnet 622. For example, as shown in FIG. 8, the movable-side stopper 62a is provided below the rotor body 621. You may make it form. Also in this case, the movable stopper 62a contacts the stopper contact portion 4b of the fixed stopper member 4 when the magnet rotor 62 rotates and descends.

  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 1A Valve chamber 11 1st joint pipe 12 2nd joint pipe 13 Valve port 2 Support member 21 Holder part 21a Male thread part 3 Valve rod (rotor shaft)
31 Needle (valve element)
4 Fixed-side stopper member (stopper mechanism)
4a Female thread part 4b Stopper contact Figure 6 Stepping motor (electric motor)
62 Magnet rotor 62a Movable side stopper (stopper mechanism)
621a Female thread 10 Body assembly 20 Valve assembly L Axis

Claims (1)

A support member which is disposed on the opposite side of the valve port with respect to the valve chamber having the valve port and has a male screw portion formed coaxially with the axis of the valve port;
A rotor shaft that is inserted through a valve guide hole formed in the support member and has a valve body portion on the valve port side;
A magnet rotor that has an internal thread portion screwed into the external thread portion of the support member, and that is fixed to the rotor shaft and constitutes an electric motor;
A stopper mechanism for regulating a lower end position of the magnet rotor with respect to the support member,
The magnet rotor is rotated by the electric motor, and the valve body part is advanced and retracted with respect to the valve port by a screw feed mechanism of the female screw part of the magnet rotor and the male screw part of the support member. A motorized valve for controlling the flow rate of fluid through the valve port,
The stopper mechanism is provided on the magnet rotor side with the fixed-side stopper member that is screwed into the male screw portion of the support member, is rotatable about the axis, and is movable in the axial direction. The stopper contact portion that protrudes at one place on the circumference of the side stopper member is configured with a movable side stopper that can contact at the lower end position of the magnet rotor,
The fixed-side stopper member is joined to the support member at an intermediate position of the male screw portion of the support member, and the intermediate position is a position corresponding to a predetermined valve opening set in the electric valve, The magnet rotor is configured to include a rotor body made of PPS resin in which the female thread portion that is screwed into the male thread portion is formed, and a magnet having a multi-pole magnetized outer peripheral portion. A motor-operated valve.

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