KR20050013057A - Motor operated valve - Google Patents

Abstract

PURPOSE: An electric valve is provided to reduce sliding resistance among a valve shaft, a push nut, and a plain washer in opening and closing a valve body and to increase durability by preventing the characteristic reduction of the push nut, the plain washer, and the valve shaft. CONSTITUTION: An electric valve(10') is composed of a valve basic body(20) for regulating the flow by a valve body(23) contacted to or separated from a valve seat(22) in a valve chamber(21) by a valve shaft(24); a can(40) fixed and stuck on the valve basic body to embed a rotor(30) for contacting and separating the valve body to/from the valve seat; and a stator(50) inserted to the outside of the can to rotate and drive the rotor. The valve shaft is disposed to slide along a push nut(33) and a plain washer(60). A plating layer(33a) with lubricating ability is formed on a sliding contact surface between the valve shaft and at least one of the push nut or the plain washer.

Description

Electric valve {MOTOR OPERATED VALVE}

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a motorized valve which is assembled and used in an air conditioner, a refrigerator, and the like, and more particularly, to a motorized valve that improves durability and lubricity of a sliding contact member of a valve shaft constituting a movable portion.

Conventionally, electric valves which are assembled and used for such types of air conditioners, refrigerators, and the like have a function of adjusting a flow rate of a fluid such as a refrigerant, and typically, through a valve body and a flange-shaped portion having a valve chamber and a valve seat. A bottomed cylindrical can is fixedly attached to the upper portion of the valve body, and a rotor is built into the inside of the can, and a stator having an insertion hole in the center portion of the can is fitted to the outside.

3 shows a longitudinal cross-sectional view of the electric valve 10 described in Patent Document 1. As shown in FIG. The electric valve 10 is fixed to the valve body 20 and the valve body 20 for adjusting the flow rate of the refrigerant by the valve body 23 which is in contact with and separated from the valve seat 22 in the valve chamber 21. A can 40 includes a rotor 30 attached to the valve body 23 to contact and separate the valve body 23, and a stator 50 fitted to the outside of the can 40 to rotate the rotor 30. The rotor 30 and the stator 50 constitute a stepping motor. In addition, the outlet and inlet pipes 20a and 20b of the refrigerant are connected to each other through the valve chamber 21 at the lower and side portions of the valve body 20.

A valve chamber 21 is formed in the valve body 20, a valve seat 22 is formed below the valve chamber 21, and a guide bush 26 is fixed and formed on the upper side. Joining with the can 40 is made by welding the end of the can 40 to the stepped portion of the flange-shaped plate 41 fixedly attached to the valve body 20 by caulking.

The can 40 has a bottomed cylindrical shape, and is fixedly attached to a flange-shaped plate 41 fixedly attached to an upper portion of the valve body 20, and the inside of the can 40 is kept closed. The stator 50 is composed of a yoke 51 made of a magnetic material, and upper and lower stator coils 53 and 53 wound around the yoke 51 through the bobbin 52 and on the outside of the can 40. A fitting hole 50a for fitting is formed. A plurality of lead terminals 54 connected to the stator coils 53 and 53 protrude from the stator 50, and a connector 56 is connected to the lead terminal 54, and a plurality of lead wires are connected to the connector 56. 55) is connected.

The valve body 23 made of the needle valve is formed at the lower end of the valve shaft 24. The drive mechanism for contacting and separating the valve body 23 with the valve seat 22 extends from the valve body 20 in the direction of the rotor 30 and is fixed, and includes a guide bush having a fixed screw portion 25 formed on its outer circumference ( 26 and a valve shaft holder 32 having a moving screw portion 31 for screwing into a fixed screw portion 25 of the guide bush 26. The fixing screw portion 25 is composed of a male screw on the outer circumference of the guide bush 26 and the moving screw portion 31 is formed as a female screw on the inner circumference of the valve shaft holder 32.

The valve shaft holder 32 has a cylindrical shape which is located outside the guide bush 26 and is opened downward, and has a moving screw portion 31 formed on the inner surface thereof, and has a valve shaft 24 at the center of the valve shaft holder 32. An upper reduction diameter portion 24b formed through a step portion 24a of the upper portion is fitted and connected by the push nut 33. The valve shaft 24 having the valve body 23 formed at the lower end thereof is inserted into the center of the valve shaft holder 32 so as to be moved up and down, and is compressed and mounted in the valve shaft holder 32 by a compression coil spring ( It is always pressed downward by 34). The lower end of the compression coil spring 34 is supported by the shoulder of the valve shaft 24, and the upper end 34a is supported by the lower surface of the valve shaft holder 32 through the flat washer 60. It is.

In addition, the valve shaft holder 32 and the rotor 30 are coupled through the support ring 36, the upper projection of the valve shaft holder 32 is fitted to the inner circumferential hole of the support ring 36, The outer periphery of the projection is fixed by caulking to engage the rotor 30, the support ring 36, and the valve shaft holder 32.

The lower stopper body 27 which comprises one side of the stopper mechanism is fixed to the guide bush 26, and the plate-shaped lower stopper piece 27a protrudes above the lower stopper body 27. As shown in FIG. Moreover, the upper stopper body 37 which comprises the other side of a stopper mechanism is fixedly attached to the valve shaft holder 32, and the plate-shaped upper stopper piece 37a protrudes toward the lower side, and it engages with the lower stopper piece 27a. Can be combined.

Further, the lower stopper body 27 is fixedly attached to the spiral groove portion 26a formed on the outer circumference of the guide bush 26, and the upper stopper body 37 is the spiral groove portion formed on the outer circumference of the valve shaft holder 32 ( It is fixed to 32b). In addition, in the side surface of the guide bush 26, a uniform pressure hole 32a is formed just below the fixing screw 25 to equalize the pressure in the space between the valve chamber 21 and the can 40. It is comprised so that circulation of a refrigerant | coolant may become easy through the pressure hole 32a.

However, in the electric valve, since the push nut 33 or the flat washer 60 is in sliding contact with the valve shaft 24 moving up and down, for example, when using a refrigerant that is difficult to contain the lubricating oil component, There is concern that durability should be improved.

On the other hand, forming a nickel plating layer containing polytetrafluoroethylene in a member whose durability tends to decrease due to friction or the like in an electric valve is described in Patent Document 2 below.

However, the nickel plating layer of patent document 2 is provided in the threaded part which engages with a valve shaft holder and a guide bush, and the problem regarding the durability of the push nut 33 or the flat washer 60 part was not solved.

[Patent Document 1] Japanese Unexamined Patent Publication No. 2003-172467

[Patent Document 2] Japanese Patent Application Laid-Open No. 8 (1996) -219317

Accordingly, the present invention has been made in view of the above problems, and an object thereof is to provide an electric valve having improved durability of a push nut or flat washer portion.

1 is a longitudinal sectional view of an embodiment of an electric valve according to the present invention.

2 is an enlarged view of a portion X in FIG. 1;

3 is a longitudinal sectional view of a conventional electric valve.

* Description of the symbols for the main parts of the drawings *

10: electric valve (conventional example) 10 ': electric valve (invention)

20: valve body 20a, 20b: outflow pipe, inflow pipe

21: valve chamber 22: valve seat

23: valve body 24: valve shaft

24a: Step portion 24b: Upper reduction diameter portion

25: fixing screw portion 26: guide bush

26a, 32b: spiral groove portion 27: lower stopper body

27a: lower stopper piece 30: rotor

31: moving screw part 32: valve shaft holder

32a: uniform pressure hole 33: push nut

33a, 60a: plating layer 34: compression coil spring

34a: end 36: support ring

37: upper stopper body 37a: upper stopper piece

40 can 41 41 flange shape plate

50: stator 50a: fitting hole

51: York 52: Bobbin

53: Stator coil 54: Lead terminal

55: lead wire 56: connector

60: flat washer

In order to achieve the above object, the electric valve according to the present invention is a valve body for adjusting the flow rate through the valve body which is in contact with and separated from the valve seat in the valve chamber by the valve shaft, and the valve body is fixedly attached to the valve body A motor operated valve having a can incorporating a rotor for contacting and separating a valve seat, and a stator fitted to an outer side of the can and rotating the rotor, wherein the valve shaft is arranged to be slidable to the push nut and the flat washer. And a plating layer having lubricity on a sliding contact surface between at least one of the push nut or the flat washer and the valve shaft. In addition, the present invention is characterized in that the plating layer is made of a material containing polytetrafluoroethylene in nickel in addition to the above structure.

In addition, the present invention is a valve body for adjusting the flow rate of the valve body in contact with the valve seat in the valve chamber by the valve shaft, and a rotor fixedly attached to the valve body to contact and separate the valve body to the valve seat In the electric valve having a can and a stator fitted to the outside of the can, the stator for rotating the rotor, the valve shaft is arranged to be slidable to the push nut and the flat washer, and the push nut to the nickel A plating layer made of a material containing tetrafluoroethylene is formed, and the flat washer is characterized in that a coating layer made of fluorine resin is formed.

FIG. 1 is a longitudinal sectional view of an embodiment of an electric valve 10 'according to the present invention, and FIG. 2 is an enlarged view of part X in FIG. EMBODIMENT OF THE INVENTION Hereinafter, in describing embodiment of this invention, the same code | symbol is attached | subjected to the part same as the structure of the electric valve 10 of the well-known example shown in FIG. 1, 2 to FIG. 3, and description is abbreviate | omitted.

As a feature of this embodiment, the surface of the push nut 33 is nickel (Ni) plated, or the surface is coated with a plating layer 33a by nickel (Ni) plating containing polytetrafluoroethylene (PTFE). It is. In the flat washer 60, a plating layer 60a made of the same material as that of the push nut 33 is formed on the surface thereof. In addition, although this process (formation of plating layers 33a and 60a) may be performed on the whole surface of the push nut 33 and the flat washer 60, at least by sliding to the sliding contact surface with other members, such as the valve shaft 24, The object of the present invention is achieved.

As described above, the surface of the push nut 33 and the flat washer 60 in sliding contact with the valve shaft 24 is subjected to the surface treatment as described above, so that the rotor 30 rotates to fix the screw 25 of the guide bush 26. The rotor 30, the valve shaft holder 32, and the valve shaft 24 are slidably moved in the axial direction by the screw feed mechanism of the moving screw portion 31 of the valve shaft holder 32. As described above, the sliding contact portion is smoothly contacted with a low coefficient of friction by the surface treatment, thereby providing a highly durable sliding contact portion.

The means of the plating is the same as the general electroless nickel plating. The plated layer of NI + PTFE has high hardness, excellent sliding performance, and high resistance to abrasion. Therefore, the valve shaft 24 can always function normally and can exhibit predetermined | prescribed performance also in the electric valve which controls the refrigerant | coolant body which improves washing | cleaning property and has low lubrication property by forming the said plating layers 33a and 60a. In addition, the plating layer may be formed on the valve shaft 24 to be opposed to the push nut 33 and the flat washer 60. In addition, a plating layer may be formed on both the push nut 33 and the flat washer 60 and the valve shaft 24.

As described above, in order to reduce the sliding movement resistance between the valve shaft 24 and the push nut 33 and the flat washer 60 when the valve body 23 is opened and closed (up and down movement of the valve shaft 24). By containing polytetrafluoroethylene in nickel as (33a, 60a), the plating layer is provided with lubricity, so that the lubricity of one or both of the push nut 33 and the flat washer 60 is ensured even without adding a lubricant. It can increase durability.

In addition, even in an environment in which a smooth flow of a refrigerator oil or the like cannot be expected in the refrigerant circuit, for example, when a carbon dioxide refrigerant is used, sliding moving parts such as a push nut 33, a flat washer 60, and a valve shaft 24 are used. It is possible to prevent the deterioration of the characteristics of the electric valve operation by increasing the durability by preventing the degradation of the characteristics.

On the other hand, in the said embodiment, although the plating layer 33a, 60a was formed in both the push nut 33 and the flat washer 60, any of these may be sufficient. Further, as another example, the push nut 33 is formed with a plating layer 33a made of a material containing polytetrafluoroethylene in nickel, and the flat washer 60 is formed with a coating layer made of fluorine resin, thereby providing a push nut. The durability of the flat washer 60 can be improved by improving the lubricity of 33 and increasing the durability of the electric valve.

The electric valve of this invention can improve durability by forming a plating layer in one or both of a push nut and a flat washer by the said structure. In addition, the sliding movement resistance between the valve shaft and the push nut and the flat washer can be reduced, particularly when the valve body is opened and closed (moving up and down of the valve shaft), so that the sliding movement can be performed smoothly and reliably. In particular, even in an environment where a smooth flow of refrigeration oil cannot be expected in the refrigerant circuit, the characteristics of sliding moving parts such as push nuts, flat washers, and valve shafts are prevented from being deteriorated, thereby increasing durability and preventing defects in electric valve operation. have.

Further, the electric valve of the present invention further comprises a plating layer made of a material containing polytetrafluoroethylene in nickel on the push nut, and a coating layer made of fluorine resin on the flat washer to form lubricity of the push nut. In addition, the durability of the flat washer can be improved, thereby increasing the durability of the electric valve.

Claims (3)

A valve body for adjusting a passage flow rate by a valve body contacted and separated by a valve shaft to a valve seat in a valve chamber, and a rotor fixedly attached to the valve body to contact and separate the valve body from the valve seat. An electric valve comprising a can and a stator fitted to an outside of the can to rotate and drive the rotor, The valve shaft is arranged to enable the sliding movement to the push nut and the flat washer, and at the same time formed by forming a lubricating plating layer on the sliding contact surface between at least one of the push nut or flat washer and the valve shaft. . The method of claim 1, And said plating layer is made of a material containing polytetrafluoroethylene in nickel. A valve body for adjusting a passage flow rate by a valve body contacted and separated by a valve shaft to a valve seat in a valve chamber, and a rotor fixedly attached to the valve body to contact and separate the valve body from the valve seat. An electric valve comprising a can and a stator fitted to an outside of the can to rotate and drive the rotor, The valve shaft is arranged to allow sliding movement to the push nut and the flat washer, and at the same time, the push nut is formed with a plating layer made of a material containing polytetrafluoroethylene in nickel, and the flat washer is formed with a coating layer made of fluorine resin. Electric valve characterized in that.