JP2001324044A - Vibration preventive device for fluid control valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a fluid control valve from generating vibration at the time of its vertical motion. SOLUTION: Generation of vibration of a valve main body 28 is restrained by inserting a stem 37 into a cylindrical main body part 28A protectively formed below the valve main body and having a through hole 28C communicated to a valve chest on its central part and the through hole 28C, interposing a seal part 52 between the main body part 28A and the stem 37 and especially deforming a Teflon (registered trade mark) resin made spacer 60 by a valve spring 26 and a manual screw 51 on the fluid control valve forming each of connecting parts to an inflow pipe and an outflow pipe of fluid on both end parts, having the valve main body 28 furnished with the valve chest 28B inside, valve bodies 38a, 38b to carry out fluid control by making contact with valve seats 28a, 28b from above the valve seats and its stem 37 in the valve chest and installing a valve diving part above the valve main body 28.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluid control valve such as a motor-operated valve and a solenoid valve, and more particularly to a fluid control valve of this type which is capable of preventing a valve shaft from vibrating near the valve closing. The present invention relates to a vibration prevention device for a fluid control valve.

Generally, a refrigeration cycle 100 includes a compressor 101, a condenser 103, an expansion valve 104, an evaporator 105, and an accumulator 106, as shown in FIG. 5 (refrigeration cycle). A pressure regulating valve 102 is provided.

[0003] As such a fluid control valve 102, a stepping motor type is conventionally known as shown in FIG. That is, this fluid control valve is
And a stepping motor M integrally fixed to an upper portion of the valve body 28 and constituting (part of) the valve driving section.

In FIG. 3, a valve chamber 28b having a pair of upper and lower valve seats 28a, 28b is provided inside a valve body 28. Lid 2 as the base of the valve drive on the top of the valve body
5, a stepping motor M
Is supported.

A pair of upper and lower valve seats 28a, 28
8b, and a valve 38 having a pair of valve portions 38a, 38b which can be attached to and detached from the respective valve seats 28a, 28b.
Is disposed. The stem 37 is
It is inserted into the hollow central shaft of the valve 38, and is pushed down by the downward movement of the needle 20 of the valve drive unit described later, and acts to push down the valve 38 at that time. The upward movement of the valve 38 is performed by the valve spring 26. Further, the valve body 28
The inflow joint 29a and the outflow joint 29b are connected to the left and right end openings, respectively. The fluid flows in the valve head portion 28 from right to left in FIG. 5, branches up and down at the valve seats 28a and 28b, and joins on the secondary side It is supposed to.

Reference numeral 5 denotes a pair of upper and lower coils, and reference numeral 15 denotes a magnet. A mandrel 1 guide 7 and a slider 9 fixed to the coil (fixed-side member) 5, magnet (rotary-side member) 15, and case 14. A stepping motor M having a normal structure is formed by a rotation stop mechanism including the spring pins 8. The coil 5 is covered with the mold 3. A lower lid receiver 24 is fixed to the lid 25, and a male screw tube 19 is fixed to the lower lid receiver 24 in an upright position. The lower cover 23 is provided around the male screw tube 19, and the case 14 is fixed on the lower cover 23.

On the outer periphery of the case 14, a stator 4 having a built-in coil 5 and having a large number of teeth arranged at equal intervals in the circumferential direction.
Is detachably provided. A female screw 18 forming the rotor R is supported and provided in the case 14 so as to be screwed into a male screw pipe 19. Reference numeral 32 indicates a gasket.

The rotor of the stepping motor M is formed by expanding the upper end of a spacer 16 attached to the inside of the magnet 15 and then integrating the two. The female screw 18 fitted and fixed below the inside of the spacer 16 is connected to the male screw tube 19. And is provided so as to be rotatable and movable in the axial direction. N poles and S poles are alternately magnetized in the magnet 15 in the circumferential direction.

A plate 17 is provided at an intermediate portion in the axial direction of the spacer 16, and the upper end of the needle 20 is welded to the small hole thereof together with the stopper 11. A spring 13 and a washer 12 are provided between the step portion of the needle 20 and the plate 17 at the small diameter portion at the upper end of the needle 20. Reference numeral 21 indicates a wave washer, and reference numeral 22 indicates a retaining ring.
The needle 20 is connected to the stem 37 via the needle receiver 35.
When the stepping motor M rotates, the needle 20 moves up and down while rotating, and in conjunction with this, the stem 37 also moves up and down while rotating.

The valve spring 26 is provided between the adjustment fitting 27 and the valve 38. The stepping motor M is airtightly fixed to the lid 25 by a hexagon socket head cap screw 30 and a gasket 31. Reference numerals 33 and 34 indicate lids, respectively. Reference numeral 35 denotes a needle receiver, 39 denotes a gasket, and 40 denotes a bottom cover. Reference numeral 6 in the figure indicates a connector.

In addition, an electromagnetic type fluid control valve as shown in FIG. 4 is known. In the fluid control valve shown in FIG. 4, when the valve is fully opened, a suction force that pushes down the plunger 04 is generated by a magnetic force corresponding to the voltage applied to the electromagnetic coil 08, and the voltage gradually increases to a specified current. At this time, the prescribed valve opening is obtained in proportion to the reaction force of the valve springs 26a and 26b. When the current further increases, the magnetic force and the valve spring 2
It has a configuration in which the stem 37 is pushed and fully opened by overcoming the reaction forces of 6a and 26b. In addition, a valve structure, a pipe joint, and the like made of the same members with the same reference numerals as those of the fluid control valve in FIG.

[0012]

As described above, the conventional fluid control valve shown in FIGS.
The output shaft of the valve drive unit, such as a valve and an electromagnetic coil, that is, the valve drive shaft is extended to the valve body and doubles as the valve shaft, so the valve drive shaft (valve shaft) becomes longer, and it is difficult to center the shaft. Operability deteriorates. Further, when the valve moves up and down and the valve starts opening from closing, there is a possibility that vibration may occur, which causes a problem of causing noise.

SUMMARY OF THE INVENTION The present invention solves the above-mentioned disadvantages of the conventional fluid control valve, and comprises a cylindrical body having a through hole formed at the center of the valve and projecting downward from the valve body to communicate with the valve chamber. A stem is inserted into the through hole, and a seal is interposed between the main body and the stem to prevent occurrence of vibration.

[0014]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention is directed to a valve body having a connection portion formed at both ends to a fluid inflow pipe and a fluid outflow pipe, and having a valve chamber therein. A fluid control valve having a valve seat that contacts the valve chamber from above and a valve body that performs fluid control by contacting the valve seat from above, and a stem that is mounted above the valve body. A cylindrical main body having a through hole formed at the center thereof and protruding below the valve main body and communicating with the valve chamber; and the stem being inserted into the through hole, the main body and the stem being A seal portion is interposed between the seal portions, which serves as means for preventing the occurrence of vibration.

Further, according to the present invention, in the above-mentioned fluid control valve, the seal portion is formed by a Teflon resin spacer, and a lower end small diameter portion of the stem is inserted into a center hole of the Teflon resin spacer. A valve spring is provided between the stem and the stem, and the pressure by the valve spring presses the bottom tapered surface of the spacer against the tapered surface of the central hole of the manual screw, thereby reducing the lower end diameter of the stem. The portion is configured to be deformed so as to press the portion, and it is possible to prevent the occurrence of vibration so as to solve the problem.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. The embodiment shown in FIG. 1 is intended for the stepping motor type fluid control valve shown in FIG. 3, and the fluid control valve of this embodiment also has
Conventionally, there is provided a stepping motor M, a stem 37 which is driven vertically by the rotation of the stepping motor M, a valve body 28 which is fitted into the stem 37 and has a built-in valve 38 having a pair of valve portions 38a and 38b. The configuration is almost the same as that of. However, in this embodiment, FIG.
Needle 2 in the fluid control valve shown in the fluid control valve shown in FIG.
0, a rotary shaft 20A having a round rod shape is used, and a ball 20 is disposed between the rotary shaft 20A and the stem 37.
B is interposed. Accordingly, although the needle receiver 35 is also omitted, there is no difference in the other configuration from that of FIG. 3. Therefore, in FIG. 1, the same members as those in FIG. 3 are denoted by the same reference numerals, and detailed description thereof will be omitted. Omitted.

The fluid control valve of this embodiment also has a valve body 2
8 at the left and right end openings, respectively, a fluid inflow joint 29a,
The outflow joint 29b is connected, and the fluid flows through the valve body 28 as shown in FIG.
, Flows from right to left, branches up and down at the valve seats 28a and 28b, and joins at the secondary side. Further, a manual valve opening device 50 is provided at a lower portion of the valve body 28.

As shown in FIG. 2, a lower end portion of the valve body 28 is provided with a protruding cylindrical body portion 28A, and a through hole 2 communicating with the valve chamber 28B is formed at the center of the body portion 28A.
8C is formed. A male screw 28e is formed on the outer peripheral surface of the main body 28A, and the bottom opening 40f of the through hole 28C at the center of the main body 28A is hermetically sealed by the gasket 39 and the bottom lid 40 having the female screw 40a screwed to the male screw 28e. It is configured as follows. Through hole 28c of valve body 28
A female screw 28g is formed in the large diameter portion at the lower end.
A manual open screw 51 having a male screw portion on the peripheral side surface to be screwed with g and having an overall shape formed into a plug shape is screwed into the through hole 28C of the main body 28A. On the bottom surface of the manual opening screw 51, a slot 5 for engaging a valve opening tool (minus screwdriver) is provided.
1B is formed.

As shown in FIG. 2, the valve spring 26 is interposed between the spacer 60 and the step 37a of the stem 37. It should be noted that a slight gap is normally formed between the lower end of the small diameter portion 37A of the lower end of the stem 37 and the bottom surface of the central fine hole 51a of the manual screw 51. In FIG.
Reference numeral 7 denotes an O-ring.

The Teflon resin spacer 60, which is the seal portion 52, is fitted into the center portion 51A of the manual screw 51, and the lower end small diameter portion 37A of the stem 37 is inserted into the center hole of the Teflon resin spacer 60. The bottom tapered surface of the Teflon resin spacer 60 is pressed against the tapered surface of the central portion 51A of the manual screw 51 by the pressure of the valve spring 26, and presses the lower end small diameter portion 37A of the stem 37. (The arrow indicates the pressing deformation direction). Thus, when opening the valve from closing the valve, it is possible to prevent the stem 38 from being pressed and the valve 38 from vibrating little by little in the vertical and horizontal directions. Further, an O-ring 61 is interposed between the manual opening screw 51 and the main body 28A to prevent the refrigerant from leaking from the inside of the valve at the time of the valve opening operation by the manual valve opening section.

In the valve closing stroke of the fluid control valve, a vibration in which the valve moves up and down is likely to occur near the valve closing. However, in this embodiment, the valve body 38a compresses the valve spring 28 as the valve closes. The compressed force is transmitted to the spacer 56 and deformed so as to give sliding resistance to the stem 37. Therefore, as the valve is closed, the force of the valve spring 26 increases, and the occurrence of the vibration can be prevented.

[0022]

According to the present invention, a spacer serving as a seal portion is provided around the extension of the valve shaft inserted into the center of the manual screw in the center hole of the manual screw, and on the inner periphery of the upper end of the manual screw. Since the tapered surface is formed at the lower end, it hits the tapered surface of the manual set screw, and the spacer can prevent the valve shaft from being pressed and the valve from vibrating in small increments in the vertical direction.

[Brief description of the drawings]

FIG. 1 is a sectional view of a fluid control valve according to an embodiment of the present invention.

FIG. 2 is an enlarged view of a seal portion in the fluid control valve of FIG.

FIG. 3 is a sectional view of a conventional fluid control valve.

FIG. 4 is a sectional view of another conventional fluid control valve.

FIG. 5 is a schematic circuit diagram of a refrigeration cycle.

[Explanation of symbols]

 Reference Signs List 1 stem 2 cap 4 stator 5 coil 7 guide 14 case 15 magnet 18 female screw 19 male screw tube 20 needle 20A rotation shaft 20B ball 25 lid 26 valve spring 27 adjusting fitting 28 valve body 28A main body 28B valve chamber 28a valve seat 28b valve seat 37 Stem 37A stem lower end small diameter portion 38 valve 40 bottom lid 50 manual valve opening device 51 manual opening screw 52 seal portion 60 spacer M stepping motor

 ──────────────────────────────────────────────────続 き Continued on the front page F-term (reference) 3H052 AA01 BA33 CD03 EA04 EA11 3H062 AA02 AA16 BB33 CC01 DD01 EE06 HH04 HH08 HH09 3H106 DA03 DA13 DA23 DB02 DB12 DB23 DB32 DC02 DC17 DD03 EE19 EE20 EE33 GC07 KK03 KK03

Claims (3)

[Claims] At each end, a connection part for a fluid inflow pipe and a fluid inflow pipe is formed, and a valve body having a valve chamber therein is provided. A valve seat is provided in the valve chamber and a valve seat is provided above the valve body. A fluid control valve in which a valve body and a stem for performing fluid control in contact with the valve body are disposed, and a valve drive unit is mounted above the valve body. A fluid, comprising: a cylindrical main body having a through-hole communicating with a chamber; a stem inserted into the through-hole; and a seal interposed between the main body and the stem. Vibration prevention device in control valve. 2. The fluid control valve according to claim 1, wherein the seal portion is formed by a Teflon resin spacer, and a lower end small diameter portion of the stem is inserted into a center hole of the Teflon resin spacer. Vibration prevention device. 3. A valve spring is provided between the spacer and the stem, and a bottom tapered surface of the spacer is pressed against a tapered surface of a center hole of the manual screw by a pressure applied by the valve spring. The vibration prevention device for a fluid control valve according to claim 2, wherein the vibration control device is configured to deform so as to press a small diameter portion at a lower end of the stem.