JPH1182796A - Motorized valve - Google Patents

Abstract

(57) [Problem] To provide a motor-operated valve provided with a bellows suitable for operating a high-pressure refrigerant. SOLUTION: A valve seat 351 of an electric valve is formed integrally with a valve body 32, a valve body 36 includes a first valve body 361 and a second valve body 362, and the first valve body 361 is a valve seat. 351 is slid in the valve main body so as to come into contact with or separate from the first valve body 361. One end of the second valve body 362 is fitted to the first valve body 361, and the other end is connected to the output shaft 2
5 and a ball 363. Bellows 41
Is, for example, when R-407 is used as an alternative refrigerant,
The number of peaks of the peak portion 402 is, for example, 14 peaks. One end of the bellows 41 is soldered to a washer 412 fixed to the valve body 32 by crimping, and the other end is a convex portion of the second valve body 362. 413 is soldered.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a motor-operated valve, and more particularly to a motor-operated valve for transmitting the output of a motor to a valve body via a gear.

[0002]

2. Description of the Related Art Conventionally, a motor-operated valve that transmits the output of a motor to a valve body via a gear has been known as a motor-operated valve. As this kind of electric valve, the electric valve having the configuration shown in FIG.
No. 0-123572. In FIG. 2, a motor 21 is built in a case 20, and a pinion 23 is fixed to a shaft 22 of the motor. Reference numeral 24 denotes a relatively thin gear that meshes with the pinion 23. An output shaft 25 is formed integrally with the gear 24 and has a cylindrical portion 26 at the upper portion and a screw portion 27 at the lower portion, sandwiching the gear.

[0003] A bearing 29 is provided on a partition wall 28 of the case 20, and supports a cylindrical portion 26 of the output shaft 25. A holder 31 is provided on a bottom portion 30 of the case 20, and a screw portion 27 of the output shaft 25 is screwed. Therefore, as described later, when the motor 21 rotates forward and backward, the pinion 23 also rotates forward and backward, and the output shaft 25 also rotates forward and reverse via the gear 24. When the output shaft 25 rotates forward and backward, the output shaft 25
Move up and down by rotation of. At this time, the pinion has a considerable height so that the gear 24 does not separate from the pinion 23.

[0004] Reference numeral 32 denotes a cylindrical valve body, a first passage 33,
There is a second passage 34 communicating with this passage. However, the two passages are respectively connected to the refrigerant pipe. Further, a valve seat 35 is fixed to a communicating portion between the first passage and the second passage by brazing or the like.

[0005] Reference numeral 36 denotes a valve body, the lower end of which faces the valve seat, and the upper end of which contacts the lower end of the output shaft 25. The abutting portion is in the form of a rotatable pivot bearing, and the lower end 37 of the output shaft and the upper end 38 of the valve body, which receive rotational friction, are each hardened by quenching to prevent wear due to friction between them. It is. The valve body 32 is provided with a partition wall 40 having a hole 39 through which the valve body can slide. Reference numeral 41 denotes a bellows having ten peaks, one end of which is hermetically attached to the inner wall of the valve body 32 and the other end of which is airtightly attached to the valve body 36, respectively. However,
The holder 31 and the valve body 32 are connected by a nut 42.

In such a configuration, when the motor 21 rotates in one direction, the pinion 23 rotates through the shaft 22,
When the flat gear 24 meshing with the pinion 23 rotates, the output shaft 25 also rotates in one direction. Due to the rotation of the output shaft 25 in one direction, the output shaft moves downward, for example, in FIG. 2, and the valve body 36 that is in contact with the lower end of the output shaft descends against the elasticity of the bellows 41. The flow rate of the refrigerant flowing through the first passage 33 and the second passage 34 is controlled.
The bellows 41 has a function of preventing the refrigerant flowing into the distal end portion of the valve body 36 from entering the motor side. Motor 2
When the output shaft 1 rotates in the other direction, the output shaft 25 rotates in the opposite direction, thereby ascending in FIG.
Numeral 6 rises due to the elasticity of the bellows 41 and causes the flow rate of the refrigerant to flow more than the above.

Now, when the valve body 36 is maintained at a predetermined opening relative to the valve seat 35, the first passage 33 and the second passage 34
When the refrigerant flows toward, the refrigerant pressure acts to push up the bellows 41, so that the valve element 36 receives a force in the opening direction in this flow direction. Therefore, output shaft 2
5 operates in a state where it is always pushed upward through the valve body 36.

Conversely, when the refrigerant flows from the second passage 34 to the first passage 33, the valve body 36 receives a load in the direction of arrow opening. It always operates when pushed up. Therefore, the refrigerant always flows into the output shaft 25
The screw portion 27 is pushed upward to flow, so that the flow rate does not change in either the forward or reverse direction, and accurate control can be performed.

[0009]

In such a conventional motor-operated valve, the use of an alternative refrigerant instead of chlorofluorocarbon, which destroys the ozone layer, has been studied from the standpoint of protecting the global environment. As an alternative refrigerant, H which does not destroy the ozone layer
The use of a mixed refrigerant in which two or more FC (hydrofluorocarbon) -based refrigerants are mixed has been considered promising.
However, when an alternative refrigerant is used, the pressure is increased by about 1.1 to 1.5 as compared with the conventional refrigerant that destroys the ozone layer. There is a problem that the reliability of the motor-operated valve may be deteriorated. In view of the above, an object of the present invention is to provide a highly reliable and highly reliable electric valve even when an alternative refrigerant is used.

[0010]

In order to achieve the above object, in the electric valve according to the present invention, the number of peaks of a bellows hermetically attached to a valve body to which rotation of a motor is transmitted via gears is replaced. The number of peaks withstands the pressure of the refrigerant.

Further, the electric valve according to the present invention is a valve body, a valve body to which the rotation of a motor shaft is transmitted via a gear, and a valve formed in the valve body where the valve body comes and comes. The seat, one end is attached to the inner wall of the valve body, the other end is composed of a bellows attached to the valve body, the bellows is configured to have the number of peaks to withstand the pressure of the alternative refrigerant. Features.

Further, the motor-operated valve of the present invention comprises a motor supported in a case, a gear meshing with a pinion rotated by the motor, an output shaft integrally formed with the gear and having a screw, A holder screwed to the shaft screw and attached to the case, a cylindrical valve body having a first passage, a second passage and fixed to the holder, and having a valve seat; One end is provided in contact with the output shaft in the form of a pivot bearing, the other end is opposed to the valve seat, a bellows is fixed at one end to the valve body, the other end is fixed to the inner periphery of the valve body. The bellows are characterized in that they have a number of peaks that can withstand the pressure of the substitute refrigerant.

According to the motor-operated valve of the present invention, the number of bellows is increased even if an alternative refrigerant having a higher pressure than the conventional refrigerant is used as the refrigerant for controlling the flow rate. The bending stress applied to each peak of the bellows during the displacement up to the time of the valve operation can be reduced, and the durability of the bellows can be improved.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing an embodiment of the present invention. The basic configuration and operation are the same as those of the conventional example shown in FIG. 2, and the number of bellows is increased in FIG. Are different. Therefore, FIG. 1 shows only a valve main body showing a main part of the present invention. In FIG. 1, the same reference numerals as those in FIG.
51 is formed integrally with the valve body 32, the valve body 36 is composed of a first valve body 361 and a second valve body 362, and the first valve body 361 is connected to and separated from the valve seat 351. The second valve body 362 is slid, and one end of the second valve body 362 is fitted to the first valve body 361, and the other end is in contact with the output shaft 25 via the spherical body 363.

In such a configuration, the output shaft 25 moves downward in FIG. 1, for example, due to the rotation of the output shaft 25 in one direction, and the second valve body 362 that is in contact with the lower end of the output shaft via the sphere 363 is Descends against the elasticity of the bellows 41,
The first valve body 361 controls the flow rate of the refrigerant flowing through the first passage 33 and the second passage 34. 1, the output shaft 25 rises in FIG. 1, the second valve body 362 rises due to the elasticity of the bellows 41, and the first valve body 361 increases the flow rate of the refrigerant in a large amount. Shed. Thus, for example, when R-407 is used as an alternative refrigerant, the bellows 41 is configured such that the number of peaks 402 is, for example, 14 peaks, and one end of the bellows 41 is fixed to the valve body 32 by swaging. Is fixed to the washer 412 by the bent portion 404a and fixed by soldering. And
The other end 406 is soldered to the projection 413 of the second valve body 362.

In this configuration, if the displacement of the valve element 36 from the time of closing the valve to the time of opening the valve is, for example, 0.7 mm, the number of bellows shown in FIG. The strain is 0.07 mm, whereas the bending strain per peak is 0.05 mm in the present embodiment, and even when an alternative refrigerant is used, the strain due to bending applied to the bellows 41 is reduced, and the bending stress is reduced. And the durability of the bellows can be improved.

In the above embodiment, the bellows 4
1 is set to, for example, 0.14 mm so that FIG.
The durability of the bellows can be further improved with respect to the conventional bellows having a plate thickness of 0.12 mm. Further, when controlling the flow rate of a refrigerant having a higher pressure as an alternative refrigerant, for example, R-407, the durability is further increased by using stainless steel instead of forming the bellows 41 of FIG. 1 with a copper alloy as the material of the bellows. Can be improved.

FIG. 3 is an explanatory view showing a part of the structure of the bellows 41 as a cross section. The bellows 41 is made of a flexible metal, and has a bent crest 40.
2, a first mounting portion 404 on the washer 412 side, and a second mounting portion 406 on the convex portion 413 of the second valve body 362. The second mounting portion 406 is bent inward, and is fixed by solder after inserting the convex portion 413 of the second valve body 36. After the first mounting portion 404 is inserted into the inner diameter portion of the washer 412, the reference numeral 404a of FIG.
As shown in (1), it is bent outward by an appropriate tool and fixed to the washer 412 by soldering.

[0019]

As described above, the motor-operated valve of the present invention is a motor-operated valve for operating the valve body by converting the rotational force of the motor into linear motion by the screw mechanism, and the metal valve attached to the outer peripheral portion of the valve body. This is an improved version of the bellows manufactured by Toshiba. The bellows has a function of preventing the refrigerant flowing into the distal end portion of the valve body from entering the motor side. The bellows expands and contracts in the axial direction, and the refrigerant is press-fitted to the outside. Therefore, pressure resistance is required together with flexibility. The present invention satisfies the above requirements and can provide a structure suitable as a motor-operated valve using an alternative refrigerant.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a main part of a motor-operated valve according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing the overall configuration of a motor-operated valve to which the present invention is applied.

FIG. 3 is a half sectional view showing the structure of the bellows shown in FIG. 1;

[Explanation of symbols]

 Reference Signs List 20 case 21 motor 23 pinion 25 output shaft 27 screw portion 32 valve body 35 valve seat 36 valve body 41 bellows 351 valve seat 361 first valve body 362 second valve body 402 mountain portion 404 first mounting portion 406 second Mounting part 412 washer 413 convex part

Claims (3)

[Claims] 1. A motor-operated valve, wherein the number of peaks of a bellows hermetically attached to a valve body to which rotation of a motor is transmitted via a gear is the number of peaks that withstands the pressure of a substitute refrigerant. 2. A valve body, a valve body to which rotation of a motor shaft is transmitted via a gear, a valve seat formed in the valve body to which the valve body comes and comes, and an inner wall of the valve body. And a bellows having one end attached to the valve body and the other end attached to the valve body, wherein the bellows has a number of peaks to withstand the pressure of the substitute refrigerant. 3. A motor supported in a case, a gear meshing with a pinion rotated by the motor, an output shaft integrally formed with the gear and having a screw, and screwed with a screw of the output shaft. A holder attached to the case, a cylindrical valve body having a first passage, a second passage and fixed to the holder and having a valve seat, and one end provided in the valve body and having one end provided with the output shaft A valve body that is in contact with a pivot bearing, the other end of the valve body facing the valve seat, one end of the valve body, and the other end of the bellows fixed to the inner circumference of the valve body, the bellows of the alternative refrigerant An electric valve characterized by having a number of peaks that can withstand pressure.