CN114135680A

CN114135680A - Electric valve

Info

Publication number: CN114135680A
Application number: CN202111444045.4A
Authority: CN
Inventors: 中川大树
Original assignee: Saginomiya Seisakusho Inc
Current assignee: Saginomiya Seisakusho Inc
Priority date: 2018-04-04
Filing date: 2019-03-12
Publication date: 2022-03-04
Anticipated expiration: 2039-03-12
Also published as: CN110345258B; JP2019183891A; CN114135680B; CN110345258A; JP7244998B2

Abstract

The invention aims to provide an electrically operated valve, which can prevent a gasket from touching a fillet part generated in the process of processing a needle housing or generating interference in the electrically operated valve of a gasket which is fixed in the needle housing of the needle and restrains the rotation of the needle caused by a rotor shaft, and can realize good operability and high durability. The electric valve (100) is provided with a washer (124) which suppresses rotation of the needle (121) caused by the rotor shaft (131) between a reduced diameter portion (125a) of the needle housing (125) and a flange portion (131b) of the rotor shaft (131) which are fixed inside the needle housing (125) of the needle (121), and is also provided with a chamfer avoidance structure (125R1), wherein the chamfer avoidance structure (125R1) prevents interference between a fillet portion generated at a bent portion of the reduced diameter portion (125a) of the needle housing (125) and the washer (124).

Description

Electric valve

The application is a divisional application; the parent application is '2019101856799', and the name of the invention is 'electric valve'.

Technical Field

The present invention relates to an electrically operated valve, and more particularly to an electrically operated valve used in a heat pump type cooling and heating system or the like.

Background

Conventionally, there is known an electrically operated valve used as an electric expansion valve or the like in a heat pump type cooling and heating system or a refrigeration system. In such an electrically operated valve, it is particularly important to convert the rotational motion of the rotor shaft caused by the rotation of the rotor driven by a stepping motor or the like into a linear motion by screwing, to move the valve element in the axial direction following the linear motion, to control the flow rate by the contact and separation of the valve element and the valve seat, and to ensure the accuracy of the axial center of the valve element and the valve seat. As such an electrically operated valve, for example, an electrically operated valve described in patent document 1 is known. Hereinafter, the configuration of the main portion of the motor-operated valve 1000 described in patent document 1 will be described with reference to fig. 6 (a) to 6 (d).

Fig. 6 (a) is a partial cross-sectional view showing the configuration of a main portion of the motor-operated valve 1000 described in patent document 1, fig. 6 (b) shows a closed valve state of the motor-operated valve 1000, fig. 6 (c) shows a state in which the motor-operated valve 1000 is returned to an opened valve state again, and fig. 6 (d) shows an enlarged view of the VId portion shown in fig. 6 (c).

As shown in fig. 6 (a), the motor-operated valve 1000 has the following configuration: a cylindrical needle housing 1025 fixed to a needle (also referred to as a valve body, but not shown here); a valve spring 1022 provided inside the needle housing 1025 so as not to directly apply a screw thrust of the rotor shaft 1031 to the needle seating portion; a spring supporter 1023 provided to improve concentricity of the valve spring 1022; and a washer 1024 provided to suppress transmission of rotation from the rotor shaft 1031 to the needle.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2017-161052

Disclosure of Invention

In the motor-operated valve, when the needle rotates in accordance with the rotation of the rotor shaft 1031 during the valve opening and closing operation in a state where the needle is in contact with the valve seat, there is a possibility that the needle and the seating portion may be worn. In order to prevent this, in the motor-operated valve 1000, as shown in fig. 6 (a), the flange portion 1031b of the rotor shaft 1031 is configured to contact the reduced diameter portion 1025a of the needle housing 1025 via a highly-sliding washer 1024, and the lower tip portion of the flange portion 1031b is configured to contact via a highly-sliding spring holder 1023.

Here, when the rotor shaft 1031 descends by a rotational movement of a rotor (not shown), the needle is pressed into the seating portion via the spring holder 1023 and the valve spring 1022, and is controlled to be in a valve-closed state. As described above, in the closed valve state shown in fig. 6 (b), the reduced diameter portion 1025a of the needle housing 1025 is not in contact with the washer 1024, the rotation of the needle housing 1025 is stopped, and the rotation of the needle fixed to the needle housing 1025 is also stopped.

Next, in the case where the electric valve 1000 shown in fig. 6 (b) is returned to the valve-opened state again from the valve-closed state, the rotor shaft 1031 needs to be reversed to pull out the needle, but when the needle is separated from the seated portion, the state shown in fig. 6 (b) is changed to the state shown in fig. 6 (c), and the flange portion 1031b of the rotor shaft 1031 comes into contact with the reduced diameter portion 1025a of the needle housing 1025 again via the washer 1024, and lifts the needle housing 1025 while rotating.

Here, as shown in fig. 6 (d), inside the bent portion where the reduced diameter portion 1025a of the needle housing 1025 is bent at a right angle, there is a possibility that a round portion 1025r generated at the time of processing becomes a problem. In other words, when the axial center of the rotor shaft is offset in the radial direction from the central axis, if the rounded portion 1025r is generated, as shown in fig. 6 (c) and 6 (d), when the reduced diameter portion 1025a of the needle housing 1025 comes into contact with the washer 1024, the washer 1024 may be brought into contact with the rounded portion 1025r of the needle housing 1025 or may interfere with the rounded portion 1025 r.

In this case, the washer 1024 is not held horizontally, and the needle housing 1025 engaged with the washer 1024 is also inclined. As a result, the inner periphery of the guide chamber (through hole 6h in patent document 1) of the guide member (valve shaft holder 6 in patent document 1), not shown, may come into contact with the outer periphery of the needle housing 1025 that rotates in accordance with the rotation of the rotor shaft 1031, and unnecessary frictional force may be generated to hinder operability. Further, if the needle housing 1025 is inclined, the needle fixed to the needle housing 1025 is inclined, and the load applied to the seating portion is biased, so that there is a possibility that the seating portion of the needle and the valve seat is unevenly worn, and there is a possibility that a problem may occur in durability.

Therefore, an object of the present invention is to provide an electrically operated valve in which a washer for suppressing rotation of a needle by a rotor shaft is provided inside a needle housing fixed to the needle, and which can prevent the washer from touching a round portion or interfering with the needle housing during processing, thereby achieving excellent operability and high durability.

In order to solve the above problem, an electrically operated valve according to the present invention includes: a valve body connected to the first joint and the second joint, and having a valve chamber and a valve seat formed therein; a rotor shaft fixed to a center of a rotor rotated by driving of a motor, and having a part formed with a male screw portion; a guide member that has a female screw portion that is screwed to the male screw portion of the rotor shaft and converts a rotational motion of the rotor into a linear motion of the rotor shaft; and a needle that moves in the valve chamber in the central axis direction in accordance with the linear motion of the rotor shaft and that is in contact with and separated from the valve seat so as to be openable and closable, the electrically operated valve further comprising: a cylindrical needle housing having a reduced diameter portion formed therein and bent at a right angle so as to face and engage with a flange portion formed at an end portion of the rotor shaft on the needle side, and having the needle fixed to the other end portion; a valve spring disposed in the needle housing in a compressed manner between the flange portion of the rotor shaft and the needle; and a washer disposed between the flange portion of the rotor shaft and the reduced diameter portion of the needle housing, wherein the electric valve further includes a chamfer relief structure that is generated when a rounded portion of a curved portion of the reduced diameter portion of the needle housing interferes with the washer.

Further, a spring holder may be further provided inside the needle housing between the rotor shaft and the needle, the spring holder may have a cylindrical shape in which a disk-shaped spring engaging portion protruding in an outer diameter direction is provided at an end portion on the rotor shaft side, and the valve spring may be disposed around the spring holder in a compressed manner between the spring engaging portion of the spring holder and the needle.

Further, the chamfer avoiding structure may be an avoiding groove formed in the central axis direction of the curved portion of the reduced diameter portion of the needle housing.

Further, the chamfer avoiding structure may be an avoiding groove formed in the outer diameter direction of the curved portion of the reduced diameter portion of the needle housing.

The chamfered relief structure may be a chamfered portion formed at a corner of the washer facing a rounded corner of the curved portion of the reduced diameter portion of the needle housing.

The chamfer escape structure may be a stepped portion formed at a corner of the washer, the stepped portion facing a rounded corner portion of the curved portion of the reduced diameter portion of the needle housing.

Further, the depth of the chamfer relief structure may be larger than the radius r of the fillet portion.

The invention has the following effects.

According to the electrically operated valve of the present invention, in the electrically operated valve including the washer that suppresses rotation of the needle by the rotor shaft in the needle housing fixed to the needle, inclination of the needle housing and the needle is suppressed by preventing the washer from touching the round portion or interfering with the needle housing during processing, and operability during rotation of the needle housing is maintained high, and uneven wear of the seating portion between the needle and the valve seat is suppressed, and durability is maintained high.

Drawings

Fig. 1 is a vertical cross-sectional view showing a schematic configuration of an electrically operated valve according to an embodiment of the present invention.

Fig. 2 (a) is a partial sectional view showing the configuration of a main portion of the motor-operated valve shown in fig. 1, and fig. 2(b) is a partial sectional view showing an enlarged portion IIb shown in fig. 2 (a).

Fig. 3 (a) is a partial sectional view showing a configuration of a main portion in a closed valve state of the electric valve shown in fig. 1, fig. 3 (b) is a partial sectional view showing a configuration of a main portion when a needle of the electric valve shown in fig. 1 is separated from a valve seat, and fig. 3 (c) is a partial sectional view showing an enlarged portion IIIc shown in fig. 3 (b).

Fig. 4 (a) is a partial sectional view showing another example of the chamfer avoiding structure of the present invention, fig. 4 (b) is a partial sectional view showing another example of the chamfer avoiding structure of the present invention, and fig. 4 (c) is a partial sectional view showing still another example of the chamfer avoiding structure of the present invention.

Fig. 5 (a) is an explanatory view for explaining an effect of the chamfer avoiding structure of the motor-operated valve shown in fig. 2(b), and fig. 5 (b) is an explanatory view for explaining an effect of the chamfer avoiding structure of the motor-operated valve shown in fig. 4 (a).

Fig. 6 (a) is a partial sectional view showing the configuration of a main portion of a conventional motor-operated valve, fig. 6 (b) is a partial sectional view showing the configuration of a main portion in a closed state of the motor-operated valve shown in fig. 6 (a), fig. 6 (c) is a partial sectional view showing the configuration of a main portion when a needle of the motor-operated valve shown in fig. 6 (a) is separated from a valve seat, and fig. 6 (d) is a partial sectional view showing an enlarged portion of VId shown in fig. 6 (c).

In the figure:

CL-center axis; 11 — a first joint; 12 — a second joint; 100. 200, 300, 400-electric valve; 110-a valve body portion; 111-a valve body; 111A-valve chamber; 111b — first port; 111c — second port; 112-a valve seat; 112 a-valve port; 120-needle portion; 121-needle; 122 — valve spring; 123. 223, 323, 423-spring support; 123 a-spring engaging portion; 124. 224, 324, 424-gasket; 125. 225, 325, 425-a needle housing; 125a, 225a, 325a, 425 a-reduced diameter portion; 125R1, 225R2, 324R3, 424R 4-chamfer avoiding structure; 130-rotor shaft rotating part; 131-rotor shaft; 131 a-external thread portion; 131b, 231b, 331b, 431 b-flange portion; 132-a guide member; 132A — a guide chamber; 132b — an internal threaded portion; 132c — pressure equalizing holes; 133-flange-like member; 140-rotor drive section; 141-a rotor; 141A-rotor chamber; 141 b-engaging protrusions; 142-rotor fixing part; 143-rotation limit spring; 144-a movable stop member; 150-an exterior part; 151-housing; 151a — a cavity; 152-a rotor support member; 152 a-an umbrella portion; 152 b-a cylindrical portion; 152c — an engagement recess; 153 — cylindrical part.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

The upper and lower concepts in the following description correspond to the upper and lower concepts in fig. 1, for example, and show relative positional relationships of the respective members, but do not show absolute positional relationships.

Fig. 1 is a longitudinal sectional view showing a schematic configuration of an embodiment 100 of an electrically operated valve according to the present invention, fig. 2 (a) is a partial sectional view showing a configuration of a main portion of the electrically operated valve 100 shown in fig. 1, and fig. 2(b) is a partial sectional view showing an enlarged portion IIb shown in fig. 2 (a).

In fig. 1 to 2(b), the motor-operated valve 100 of the present invention is a motor-operated valve used mainly as an electric expansion valve or the like in a heat pump type cooling and heating system or a refrigeration system. The electric valve 100 includes: a valve body 110 having a valve chamber 111A formed therein; a needle portion 120 housed in the valve chamber 111A; a rotor shaft rotating part 130 connected to the needle part 120; a rotor driving unit 140 for driving the rotor shaft rotating unit 130; and an exterior part 150 connected to the valve body part 110 and housing the rotor shaft rotating part 130 and the rotor driving part 140 therein.

The valve body 110 includes a valve body 111 and a valve seat 112.

The valve main body 111 is formed by processing a metal material such as a stainless steel plate by press working or the like. The valve body 111 is formed with a valve chamber 111A in which a needle 121 described later is housed. A first port 111b to which the first joint 11 is connected is formed in a side wall of the valve chamber 111A, and a second port 111c to which the second joint 12 is connected is formed in a bottom surface of the valve chamber 111A.

Here, the first joint 11 and the second joint 12 are both made of copper or stainless steel, and are fixed to the valve main body 111 by brazing, welding, or the like, but the present invention is not limited thereto. In the present embodiment, the case where the first port 111b is the input side and the second port 111c is the output side as the refrigerant flow is described, but the present embodiment is not limited to this, and the motor-operated valve 100 of the present embodiment is a two-way corresponding type motor-operated valve that can be used even where the first port 111b is the output side and the second port 111c is the input side.

The valve seat 112 is made of a metal material such as stainless steel or a copper alloy, and is fixed to the valve main body 111 around the second port 111c to which the second joint 12 is connected by welding, brazing, or the like. The valve seat 112 has a through hole penetrating through the center thereof, and a valve port 112a connected to the second joint 12 via a second port 111 c. The valve port 112a is in contact with and separated from a needle 121 described later, thereby controlling the opening and closing of the valve. Here, the valve seat 112 is a member independent from the valve main body 111, but may be integrally formed with the valve main body 111 if there is no problem in durability or operability.

The needle 120 includes a needle 121, a valve spring 122, a spring holder 123, a washer 124, and a needle housing 125.

The needle 121 is also called a valve body, and is formed of a metal material such as stainless steel, for example, and is driven in the center axis CL direction by a rotor shaft 131 described later or the like, thereby controlling opening and closing of the valve. The needle 121 has a shape in which the center thereof protrudes smoothly on the side contacting the valve port 112a, and the effective opening area is formed to increase and decrease quantitatively by the opening and closing control of the valve port 112 a. A substantially cylindrical needle housing 125 described later is fixed by welding to the rotor shaft 131 side of the needle 121, and a valve spring 122 is held inside the needle housing.

The valve spring 122 is disposed inside the substantially cylindrical needle housing 125 and is disposed between the needle 121 and a spring engagement portion 123a of a spring holder 123 described later in a compressed manner. Further, the provision of the valve spring 122 has an effect of preventing a screw thrust force generated by the rotor shaft 131 and the like described later from being directly applied to the needle 121, the valve port 112a, and the like, and thus has an effect of improving the durability of the electric valve 100.

The spring holder 123 is formed in a substantially cylindrical shape by, for example, resin or the like, and is disposed along the center axis CL between a rotor shaft 131, which will be described later, and the needle 121 in the substantially cylindrical needle housing 125 and inside the valve spring 122. A disk-shaped spring engaging portion 123a protruding in the outer diameter direction is formed at an end portion of the spring holder 123 on the side contacting the rotor shaft 131.

Further, the spring holder 123 is provided and disposed along the center axis CL inside the valve spring 122, thereby improving concentricity of the valve spring 122 and improving the operability. When the spring holder 123 is not provided, the valve spring 122 is disposed so as to be compressed between a flange portion 131b of the rotor shaft 131 and the needle 121, which will be described later.

The washer 124 is formed in an annular shape of, for example, a high-slip resin, and is disposed between a flange portion 131b of the rotor shaft 131 described later and a reduced diameter portion 125a of the needle housing 125 described later. Further, by providing the washer 124, the rotation of the rotor shaft 131 can be suppressed from being directly transmitted to the needle 121. This suppresses the rotation of the needle 121, and prevents the needle 121 and the valve port 112a of the valve seat 112 from being worn.

The needle housing 125 is formed into a substantially cylindrical shape by press working or the like from a metal material such as stainless steel. A reduced diameter portion 125a bent at a right angle is formed inside the end portion of the needle housing 125 on the rotor shaft 131 side. The needle housing 125 has a function of transmitting a screw driving force of the rotor shaft 131 and the like described later to the needle 121. The reduced diameter portion 125a of the needle housing 125 is disposed to face and engage with a flange portion 131b of the rotor shaft 131, which will be described later. The needle 121 is fixed to an end portion of the needle housing 125 opposite to the reduced diameter portion 125a by welding or the like.

The rotor shaft rotating portion 130 includes a rotor shaft 131, a guide member 132, and a flange-like member 133.

The rotor shaft 131 is formed of, for example, a metal material, is formed into a rod shape having a substantially circular cross section, and is disposed to extend vertically along the center axis CL of the motor-operated valve 100. The rotor shaft 131 is fixed to the center of a rotor 141 rotated by a motor such as a stepping motor described later by a rotor fixing member 142 described later, and rotates around a center axis CL in accordance with the rotation of the rotor 141.

A male screw portion 131a is formed in a portion of the rotor shaft 131 closer to the needle 121 than the rotor fixing member 142, and is screwed to a female screw portion 132b of the guide member 132 described later. A flange portion 131b protruding in an outer diameter direction in a circular disk shape is formed at an end portion of the rotor shaft 131 on the needle 121 side. The flange portion 131b is disposed inside the needle housing 125 closer to the needle 121 than the diameter-reduced portion 125a, and has a larger diameter than the diameter-reduced portion 125a, thereby serving as a retaining member.

The guide member 132 is formed of, for example, resin into a substantially cylindrical shape, and has a female screw portion 132b formed in an upper portion of a through hole having a circular cross section along the center axis CL of the motor-operated valve 100, and is screwed to the male screw portion 131a of the rotor shaft 131. The guide member 132 has a function of converting a rotational motion of the rotor 141, which will be described later, into a linear motion of the rotor shaft 131 by the screw coupling.

A guide chamber 132A is formed in the center of the guide member 132 on the needle 121 side, and the guide chamber 132A slidably accommodates the needle housing 125 in accordance with the movement of the needle 121. Further, a pressure equalizing hole 132c is provided in a part of the guide chamber 132A. This allows the guide chamber 132A to communicate with a rotor chamber 141A described later, thereby facilitating movement of the rotor shaft 131 and the needle housing 125. Further, a flange-like member 133 is fixed to the guide member 132 near the middle section of the outer periphery thereof.

The flange-like member 133 is a metal disk-like member and is fixed to the guide member 132. The flange-like member 133 is fixed to the valve main body 111 by welding or the like. Thereby, the guide member 132 is fixed to the valve main body 111 via the flange-like member 133 so as not to be rotatable.

The rotor driving unit 140 includes a rotor 141, a rotor fixing member 142, a rotation restricting spring 143, and a movable restricting member 144.

The rotor 141 is housed in a rotor chamber 141A in a housing 151 described later, and is configured by a multi-pole permanent magnet in which N-poles and S-poles made of a ferrite sintered body or the like are alternately arranged. In the present embodiment, the rotor 141 is disposed on the outer periphery of a housing 151 described later, and constitutes a stepping motor together with a stator composed of a yoke, a bobbin, a coil, and the like, which are not shown. Although the stepping motor is used here, the stepping motor is not limited to this, and similar operational effects can be obtained even when another motor that can rotationally drive the rotor 141 is used.

The rotor fixing member 142 is provided at the center of the rotor 141, and fixes the rotor 141 and the rotor shaft 131 by press fitting or the like.

The rotation restricting spring 143 has a coil spring shape and is disposed around a cylindrical portion 152b of the rotor support member 152, which will be described later. The rotation restricting spring 143 has an upper end fixed to the upper portion of the cylindrical portion 152b of the rotor support member 152, and a lower end engaged and fixed to the movable restricting member 144.

The movable stopper member 144 has a coil spring shape with 1 turn, and is rotatably disposed around the cylindrical portion 152b of the rotor support member 152. One end of the movable stopper member 144 is engaged with an engagement projection 141b integrally formed on a predetermined one of the poles of the rotor 141 having multiple poles, and the other end is engaged with a lower end of the rotation stopper spring 143. With such a configuration, the rotation restricting spring 143 is disposed on the center axis CL of the motor-operated valve 100 without play, and the rotor 141 that is rotationally driven smoothly returns to a predetermined position via the movable restricting member 144 by the spring force of the rotation restricting spring 143.

The exterior part 150 includes a housing 151, a rotor support member 152, and a cylindrical member 153.

The case 151 is formed by processing a nonmagnetic metal such as a stainless steel plate into a cup shape by press working or the like. The circular lower end portion of the housing 151 is hermetically fixed by butt welding with the circular upper end portion of the valve main body 111 over the entire circumference by TIG welding, plasma welding, laser welding, or the like. Further, a pocket 151a is formed in the housing 151, and the pocket 151a is engaged with an engagement recess 152c formed in an umbrella portion 152a of the rotor support member 152, which will be described later.

The rotor support member 152 is formed of a stainless steel plate or the like by press working or the like, and includes an umbrella portion 152a fixed in contact with the housing 151 and a cylindrical portion 152b extending downward from the center of the umbrella portion 152 a. An engaging recess 152c is formed in the umbrella-shaped portion 152a, and the rotor support member 152 is fixed to a predetermined mounting position of the housing 151 in a non-rotatable manner by engagement of the engaging recess 152c with the pocket 151a of the housing 151.

The cylindrical member 153 is made of a material having high lubricity, such as metal or synthetic resin, and is disposed inside the cylindrical portion 152b of the rotor support member 152 to rotatably hold the upper end portion of the rotor shaft 131.

The operation of the motor-operated valve 100 of the present invention configured as above will be described.

Fig. 3 (a) is a partial sectional view showing the configuration of a main part of the valve-closed state of the motor-operated valve 100 shown in fig. 1, fig. 3 (b) is a partial sectional view showing the configuration of a main part when the needle and the valve seat of the motor-operated valve 100 shown in fig. 1 are separated, and fig. 3 (c) is a partial sectional view showing an enlarged portion IIIc shown in fig. 3 (b).

When the motor-operated valve 100 of the present invention is driven, first, a drive pulse signal is applied to the stator, whereby the rotor 141 rotates according to the number of pulses, and the rotor shaft 131 rotates in conjunction with this, and the rotor shaft 131 rotates and moves along the center axis CL by the engagement of the male screw portion 131a of the rotor shaft 131 with the female screw portion 132b of the guide member 132.

When the motor-operated valve 100 is closed, the rotor shaft 131 needs to be moved downward. When the rotor shaft 131 further moves downward after the needle 121 comes into contact with the valve seat 112, as shown in fig. 3 (a), the valve spring 122 is compressed via the spring holder 123, the needle 121 is pressed against the valve seat 112 by a load due to a reaction force of the valve spring 122, and the electric valve 100 is controlled to be in a reliably closed valve state.

At this time, since the needle 121 is pressed against the valve seat 112 via the spring holder 123 and the valve spring 122, the frictional resistance of the seating surface is larger than the frictional resistance between the rotor shaft 121 and the high-slip spring holder 123, and the rotating rotor shaft 131 slides between the spring holder 112, thereby suppressing the transmission of the rotation to the needle housing 125 and the needle 121. This suppresses wear of the needle 121 and the valve port 112 a. Further, since the rotor shaft 131 is press-fitted, the washer 124 descends together with the flange portion 131b of the rotor shaft 131, so that the upper surface of the washer 124 does not contact the lower end surface of the reduced diameter portion 125a of the needle housing 125, and the rotation of the needle housing 125 is also stopped.

Next, when the motor-operated valve 100 is returned from the valve-closed state of fig. 3 (a) to the valve-opened state, the rotor shaft 131 is reversed and moved upward. Before the state of fig. 3 (a) is changed to the state of fig. 3 (b), the valve spring 122 is extended via the spring holder 123 in accordance with the rise of the rotor shaft 131. At this time, the needle valve 121 is kept in contact with the valve seat 112. When the rotor shaft 131 further moves upward, as shown in fig. 3 (b), the flange portion 131b of the rotor shaft 131 comes into planar contact with the reduced diameter portion 125a of the needle housing 125 via the washer 124, and lifts the needle housing 125 while rotating. When the needle housing 125 is lifted, the needle 121 fixed to the needle housing 125 also moves upward, the needle 121 does not contact the valve port 112a of the valve seat 112, and the electric valve 100 is controlled to be in the open state.

At this time, the needle housing 125 and the needle 121 are driven by the rotor shaft 131 via the high-slip washer 124, and therefore, the rotation of the rotor shaft 131 is suppressed from being transmitted to the needle housing 125 and the needle 121. This suppresses wear of the needle 121 and the valve port 112 a.

Further, the space between the needle housing 125 and the flange portion 131b of the rotor shaft 131 and the space between the reduced diameter portion 125a of the needle housing 125 and the rotor shaft 131 are formed to be rotatable and have a gap, so that the operability is improved. Therefore, as shown in fig. 3 (b), when the needle housing 125 is lifted, the flange portion 131b of the rotor shaft 131 and the washer 124 may be biased to contact the reduced diameter portion 125a of the needle housing 125.

On the other hand, the reduced diameter portion 125a of the needle housing 125 is formed by press working, cutting, or the like, but a round portion of about 0.1mm to 0.3mm may be generated inside the bent portion of the reduced diameter portion 125a bent at a right angle due to a tolerance or the like in the working, and in order to completely remove the round portion, another means such as electric discharge machining is required, which is difficult from the viewpoint of cost.

As shown in fig. 6 (d), in the conventional motor-operated valve 1000, when the rounded portion 1025r is generated in this way, the washer 1024 may touch or interfere with the rounded portion, and the washer 1024 is not held horizontally. Accordingly, the needle housing 1025 engaged with the washer 1024 is inclined, and the outer periphery of the needle housing 1025 comes into contact with the inner periphery of a guide chamber of a guide member, not shown, and an unnecessary frictional force is generated, and the needle housing 1025 and the needle rotating in accordance with the rotation of the rotor shaft 1031 are inclined, thereby hindering operability. Further, when the needle housing 1025 is tilted, the needle fixed to the needle housing 1025 is tilted, and thus a load bias applied to the seating portion is also generated, and the needle or the seating portion may be unevenly worn.

In order to solve the conventional problems, the motor-operated valve of the present invention has a chamfer avoiding structure. In the motor-operated valve 100 of the present embodiment, as shown in fig. 2(b) and 3 (c), an escape groove 125R1 in the center axis CL direction is formed as a chamfered escape structure, and the escape groove 125R1 in the center axis CL direction is formed at the curved portion of the reduced diameter portion 125a of the needle housing 125. The relief groove 125R1 in the center axis CL direction can be formed by press working, cutting, or the like.

Here, an effect of the chamfer avoiding structure of the motor-operated valve 100 shown in fig. 2(b) will be described with reference to fig. 5 (a). Fig. 5 (a) is an explanatory diagram for explaining an effect of the chamfer avoiding structure of the motor-operated valve 100 shown in fig. 2 (b).

As described above, the radius r of the rounded portion formed inside the bent portion of the reduced diameter portion 125a bent at a right angle is about 0.1mm to 0.3mm due to a tolerance or the like during machining. On the other hand, in the motor-operated valve 100 shown in fig. 5 (a), an escape groove 125R1 is formed in the center axis CL direction, and the depth from the inner plane of the reduced diameter portion 125a is H1. Here, as is clear from fig. 5 (a), when the groove depth H1 is deeper than the radius r of the rounded portion, interference or contact between the washer 124 and the rounded portion disappears.

By forming the relief groove 125R1 in the direction of the central axis CL in this way, the washer 124 can be held horizontally even when a rounded portion is generated, whereby the inclination of the needle housing 125 and the needle 121 engaged with the washer 124 can be suppressed, the operability during rotation of the needle housing 125 can be held high, uneven wear of the needle 121 and the valve port 112a can be suppressed, and the durability can be held high.

Next, a modified example of the motor-operated valve 100 of the present invention will be described.

Fig. 4 (a) is a partial cross-sectional view showing another example 200 of the chamfer avoiding structure of the present invention, fig. 4 (b) is a partial cross-sectional view showing another example 300 of the chamfer avoiding structure of the present invention, and fig. 4 (c) is a partial cross-sectional view showing another example 400 of the chamfer avoiding structure of the present invention.

As shown in fig. 4 (a), the chamfer avoiding structure of the present invention may be formed with an avoiding groove 225R2 in the outer diameter direction, and the avoiding groove 225R2 in the outer diameter direction may be formed at a curved portion of the reduced diameter portion 225a of the needle housing 225. The relief groove 225R2 in the outer diameter direction can be formed by press working, cutting working, or the like.

Here, an effect of the chamfer avoiding structure of the motor-operated valve 200 shown in fig. 4 (a) will be described with reference to fig. 5 (b). Fig. 5 (b) is an explanatory diagram for explaining an effect of the chamfer avoiding structure of the motor-operated valve 200 shown in fig. 4 (a).

In the motor-operated valve 200 shown in fig. 5 (b), an escape groove 225R2 is formed in the outer diameter direction, and the depth from the cylindrical inner circumferential surface of the needle housing 225 is H2. Here, as is clear from fig. 5 (b), when the groove depth H2 is deeper than the radius r of the rounded corner, interference or contact between the washer 224 and the rounded corner disappears. In this way, if the depth of the chamfer avoiding structure is larger than the radius r of the fillet portion, the operational effect of the present invention can be obtained.

As described above, even if the relief groove 225R2 in the outer diameter direction is formed as the chamfer relief structure, the same operational effect as that of the relief groove 125R1 in the center axis CL direction shown in fig. 1 to 3 (c) can be obtained.

As shown in fig. 4 (b), the chamfer avoiding structure of the present invention may be configured such that a chamfer portion 324R3 formed at a corner of the washer 324 facing a rounded corner of the curved portion of the reduced diameter portion 325a of the needle housing 325 is formed. The chamfered portion 324R3 can be formed by cutting or the like.

As shown in fig. 4 (c), the chamfer escape structure of the present invention may be formed with a step portion 424R4 formed at a corner of the washer 424 facing a rounded portion of the curved portion of the reduced diameter portion 425a of the needle housing 425. The step portion 424R4 can be formed by cutting or the like.

As described above, even when the chamfered portion 324R3 or the stepped portion 424R4 is formed at the corner of the gasket as shown in fig. 4 (b) and 4 (c), the chamfered structure can obtain the same operational effect as the relief groove 125R1 in the center axis CL direction shown in fig. 1 to 3 (c).

As described above, according to the motor-operated valve of the present invention, in the motor-operated valve including the washer that suppresses the rotation of the needle by the rotor shaft in the needle housing fixed to the needle, the inclination of the needle housing and the needle can be suppressed by preventing the washer from touching the round portion or interfering with the needle housing during processing, and the operability of the needle housing during rotation can be maintained high, and the durability can be maintained high by suppressing uneven wear of the needle and the seating portion.

Claims

1. An electrically operated valve comprising:

a valve body connected to the first joint and the second joint, and having a valve chamber and a valve seat formed therein;

a rotor shaft fixed to a center of a rotor rotated by driving of a motor, and having a part formed with a male screw portion;

a guide member that has a female screw portion that is screwed to the male screw portion of the rotor shaft and converts a rotational motion of the rotor into a linear motion of the rotor shaft; and

a needle that moves in the valve chamber in the central axis direction in accordance with the linear motion of the rotor shaft and is in contact with and separated from the valve seat so as to be openable and closable,

the electrically operated valve is characterized by further comprising:

a cylindrical needle housing having a reduced diameter portion formed therein and bent at a right angle so as to face and engage with a flange portion formed at an end portion of the rotor shaft on the needle side, and having the needle fixed to the other end portion; and

a washer disposed inside the needle housing between the flange portion of the rotor shaft and the reduced diameter portion of the needle housing,

the electric valve is also provided with a chamfer avoiding structure which prevents the gasket from contacting a fillet part generated at the bending part of the reducing part of the needle shell,

the round part is a round part connecting the reduced diameter part of the needle housing and the inner circumferential surface of the needle housing,

the chamfer avoiding structure is configured such that an outer peripheral surface of the washer, which is contactable with the inner peripheral surface of the needle housing, is located on the flange portion side with respect to a boundary between the inner peripheral surface of the needle housing and the round portion in a state where the washer is in contact with the reduced diameter portion, and such that a plane of the washer, which is contactable with the reduced diameter portion of the needle housing, is located on the central axis side with respect to a boundary between the reduced diameter portion of the needle housing and the round portion in a state where the washer is in contact with the inner peripheral surface of the needle housing,

the chamfer avoiding structure is provided in the axial direction of the reduced diameter portion of the needle housing, in the radial direction of the inner peripheral surface of the needle housing, or in both planes of the washer.

2. Electrically operated valve according to claim 1,

the receding portion formed by the chamfer receding structure is provided in the inner diameter direction with respect to the inner peripheral surface of the needle housing.

3. Electrically operated valve according to claim 1,

the washer is located on the side of the flange on the side of the boundary between the inner peripheral surface and the rounded portion, compared to the rotor-side end of the outer peripheral surface facing the inner peripheral surface of the needle housing.

4. Electrically operated valve according to claim 2 or 3,

the chamfer avoiding structure is arranged on the connecting part of the reducing part and the bending part along the axial direction,

the inner peripheral surface and the chamfer avoiding structure are connected at the fillet part,

in a state where the washer is in contact with the reduced diameter portion, an outer peripheral surface of the washer that is in contact with the inner peripheral surface of the needle housing is located on the flange portion side of a boundary between the inner peripheral surface of the needle housing and the rounded portion.

5. Electrically operated valve according to claim 1,

the annular chamfer avoiding structure is arranged on the connecting part of the inner peripheral surface and the bending part along the radial direction,

the reduced diameter portion and the receding portion are connected to each other at the rounded portion,

in a state where the washer is in contact with the inner peripheral surface of the needle housing, a plane of the washer that can be in contact with the reduced diameter portion of the needle housing is located on a central axis side of a boundary between the reduced diameter portion of the needle housing and the rounded portion.

6. Electrically operated valve according to claim 2 or 3,

the chamfer avoiding structure is arranged on two planes of the gasket in a circular ring shape.

7. Electrically operated valve according to one of the claims 1 to 6,

a valve spring disposed in a compressed manner between the flange portion of the rotor shaft and the needle,

a spring support is arranged in the needle housing and between the rotor shaft and the needle,

the spring holder has a cylindrical shape provided with a disk-shaped spring engaging portion protruding in an outer diameter direction at an end portion on the rotor shaft side,

the valve spring is disposed in a compressed manner around the spring holder and between the spring engaging portion of the spring holder and the needle.

8. Electrically operated valve according to claim 2 or 3,

the chamfer avoiding structure is an avoiding groove formed in the central axis direction of the curved portion of the reduced diameter portion of the needle housing.

9. Electrically operated valve according to claim 1,

the chamfer avoiding structure is an avoiding groove formed in the outer diameter direction of the curved portion of the reduced diameter portion of the needle housing.

10. Electrically operated valve according to claim 2 or 3,

the chamfer avoiding structure is a chamfer part formed at the corner of the washer, which is opposite to the fillet part of the bending part of the diameter reducing part of the needle housing.

11. Electrically operated valve according to claim 2 or 3,

the chamfer avoiding structure is a step part formed at a corner of the washer, which faces a rounded corner of the curved part of the reduced diameter part of the needle housing.

12. Electrically operated valve according to one of the claims 1 to 11,

the depth of the chamfer avoiding structure is larger than the radius r of the fillet part.