KR101462418B1 - A Variable Capacity Control Valve - Google Patents

Abstract

The present invention relates to a bellows casing in which a through hole is formed in a lower surface and an upper end is opened; A bellows which is expanded and contracted upward and downward and opened at a lower end thereof, a coil spring provided inside the bellows, a support plate coupled with a lower end portion of the bellows which is opened and having a lower surface hole, and a sealing member sealing the lower surface hole, A bellows assembly inserted through the top portion; A set screw which hermetically seals the through hole and supports the lower surface of the support plate; And a valve housing accommodating a valve rod provided at an upper end of the bellows and being installed at an upper end of the bellows casing.
According to the present invention, since the bellows and the support plate are welded at room temperature, the automation is facilitated and the flowability of the melt is improved, so that the seal between the bellows and the support plate can be reliably ensured and the defect rate associated with the seal can be reduced. In addition, by welding the bottom plate of the support plate and the sealing member in a vacuum chamber, the amount of welding under vacuum is drastically reduced, so that the vacuum degree in the bellows can be easily managed, maintained and maintained. There is an effect to be achieved.

Description

[0001] The present invention relates to a variable capacity control valve,

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a variable capacity type control valve, and more particularly, to a variable capacity type control valve that is used in a compressor and changes the degree of refrigerant supply amount by opening and closing a ball valve through upward and downward movement of a valve rod.

The variable displacement type control valve is used in a compressor. The bellows in the bellows casing, which communicates with the suction chamber of the compressor, expands or contracts in accordance with the pressure of the suction chamber. This causes the valve rod contacting the upper surface of the bellows to move up and down, and the valve rod moves the ball valve located at the upper end portion up and down to control the supply amount of the refrigerant gas.

The bellows, which is stretched or shrunk vertically according to the pressure of the suction chamber, is made to be close to the vacuum so that the bellows pressure is not affected by changes in the outside temperature and altitude. Accordingly, Korean Patent Laid-Open No. 10-2008-0022305, filed by the applicant of the present invention, in order to make the interior of the bellows into a vacuum state, has a structure in which, as shown in FIG. 1, in the vacuum chamber, And the upper surface of the bellows support 20 are welded together to form a welded portion 50, the inside of the bellows is made to be in a vacuum state.

The conventional method shown in FIG. 1 has a problem in that it is necessary to maintain a vacuum state until the welded material melts in the vacuum chamber, takes a long time to harden, and hardens.

Further, since the vacuum is welded over a wide range along the contact portion between the lower end portion of the bellows and the upper surface of the bellows support, there is a problem that partial sealing is not achieved when the flow condition of the welded portion becomes poor.

And it is difficult to uniformly maintain the vacuum state inside the vacuum chamber due to a large amount of gas generated in the welding process.

In addition, since the valve housing and the bellows casing are coupled with each other by the curling method in the vacuum chamber, the manufacturing process is complicated, the process steps are lengthened, and the vacuum state in the bellows is maintained There has been a problem in that there is a difficulty in doing so.

The control valve using the diaphragm has a structural problem in that the displacement amount of the valve rod is not constant according to the pressure change of the suction chamber of the compressor.

SUMMARY OF THE INVENTION Accordingly, the present invention has been made keeping in mind the above problems occurring in the prior art,

Since the bellows and the support plate are welded at room temperature, the automation is easy and the flowability of the melt is improved. Accordingly, the seal between the bellows and the support plate can be surely secured. In the vacuum chamber, the bottom plate and the sealing member are spot welded, And the vacuum degree in the bellows can be easily managed and maintained.

The bellows casing and the valve housing are hermetically sealed by an O-ring, and then the bellows casing and the valve housing are combined with each other to form a control valve. A variable capacity type control valve that is easy to maintain and repair, and can simplify a component configuration.

It is another object of the present invention to provide a variable displacement control valve capable of precisely controlling the opening and closing of a valve by stably supporting the upward and downward movement of the valve rod by inserting the valve rod bottom end into the recess formed in the upper surface of the bellows.

The problems to be solved by the present invention are not limited to those mentioned above, and other solutions not mentioned can be clearly understood by those skilled in the art from the following description.

Means for attaining the object of the present invention are a bellows casing in which a through hole is formed in a lower surface and an upper end is opened; A bellows which is expanded and contracted upward and downward and opened at a lower end thereof, a coil spring provided inside the bellows, a support plate coupled with a lower end portion of the bellows which is opened and having a lower surface hole, and a sealing member sealing the lower surface hole, A bellows assembly inserted through the top portion; A set screw which hermetically seals the through hole and supports the lower surface of the support plate; And a valve housing accommodating a valve rod provided at an upper end of the bellows and being installed at an upper end of the bellows casing.

Further, the lower end of the bellows is coupled with the support plate through welding at room temperature, and the bottom hole and the sealing member are coupled through spot welding in the vacuum chamber.

The bellows assembly further includes a stopper for limiting a vertical movement range of the bellows, wherein the stopper is provided so as to surround the outer circumferential surface by a coil spring.

Further, a depression at a predetermined depth is formed on the upper surface of the bellows contacting the valve stem, and a lower end of the valve stem is inserted into the depression.

Further, the combination of the bellows casing and the valve housing is sealed by the O-ring and coupled in a curling manner.

According to the present invention, since the bellows and the support plate are welded at room temperature, the automation is facilitated and the flowability of the melt is improved, so that the seal between the bellows and the support plate can be reliably ensured and the defect rate associated with the seal can be reduced.

In addition, by welding the bottom plate of the support plate and the sealing member in a vacuum chamber, the amount of welding under vacuum is drastically reduced, so that the vacuum degree in the bellows can be easily managed, maintained and maintained. There is an effect to be achieved.

The bellows casing and the valve housing are hermetically sealed by an O-ring, and then the bellows casing and the valve housing are combined with each other to form a control valve. Maintenance and repair. Further, since the variable capacity type control valve according to the present invention is an assembly of a simple component structure, the working time is reduced and the cost is reduced.

Further, the lower end of the valve rod is inserted into the depression formed on the upper surface of the bellows to stably support the upward and downward movement of the valve rod, thereby opening and closing the valve precisely.

The effects of the present invention are not limited to those mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the following description.

1 is a sectional view showing a conventional variable capacity type control valve.
2 is a perspective view of a variable capacity type control valve according to an embodiment of the present invention;
3 is an exploded perspective view of a variable capacity type control valve according to an embodiment of the present invention.
4 is a cross-sectional view of a variable capacity type control valve according to an embodiment of the present invention.
5 is a sectional view of a variable capacity type control valve according to another embodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the configuration of a variable capacity control valve according to a preferred embodiment of the present invention will be described in detail with reference to the accompanying drawings.

FIG. 2 is a perspective view of a variable capacity type control valve according to an embodiment of the present invention, FIG. 3 is an exploded perspective view of a variable capacity type control valve according to an embodiment of the present invention, Sectional view of the variable capacity type control valve according to the second embodiment of the present invention.

2 to 4, a variable capacity type control valve 1 according to an embodiment of the present invention includes a bellows casing 100, a bellows assembly 200, a set screw 300, a valve housing 400 And a filter unit 500 and the like.

The bellows casing 100 is a constituent element for accommodating the bellows assembly 200 to be described below, which is expanded and contracted in a predetermined range up and down. The bellows casing 100 is formed in a cylindrical shape with a through hole 110 formed in the lower surface thereof, A space for accommodating the bellows assembly 200 is provided.

A plurality of first ports 120, which are communicated with a suction chamber (not shown) of the compressor, through which suction pressure Ps acts, may be provided on the outer circumferential surface of the bellows casing 100. The first port 120 is formed at every 90 ° angle along the outer circumferential surface of the cylindrical bellows casing 100 to form a total of four or 180 ° angles so that a total of two first ports 120 .

O "of the rubber material for packing so that the pressure of the refrigerant gas of the compressor is completely transmitted to the inner space of the bellows casing 100 through the first port 120 by being tightly inserted into the compressor at the outer peripheral surface of the lower end of the bellows casing 100, Shaped first O-ring 130 is provided.

The bellows assembly 200 is an assembly in which the inner space of the bellows 210 is formed in a vacuum state so that the bellows 210 will not be influenced by changes in the pressure of the bellows casing 100 Is inserted through the opened upper end and is seated on the inner bottom surface of the bellows casing (100). The bellows assembly 200 is a component having the main technical features in the present invention.

The bellows assembly 200 may include a bellows 210, a coil spring 220, a support plate 230, a sealing member 240, a stopper 250, and the like.

The bellows 210 is a constituent element that can be stretched in the up-and-down direction in Fig. 2, and has a lower end portion in an open shape and an upper end portion in a cylindrical shape having a closed structure. A coil spring 220 is provided in the inner space of the bellows 210. One end of the coil spring 220 supports the upper surface of the inner side of the bellows 210 and the other end supports the support plate 230 to generate an elastic force against the expansion and contraction of the bellows 210 to maintain the shape of the bellows 210 .

At this time, the stopper 250 stably supports the upper surface of the bellows 210, which is pressurized when external pressure is transmitted to the pressure chamber 140 through the first port 120 of the bellows casing 100, The elastic member 210 is provided inside the bellows 210 so that the outer circumferential surface of the bellows 210 is wrapped by the coil spring 220.

More specifically, the upper end of the stopper 250 is formed of an expansion part 250a to stably support the upper surface of the bellows 210. A rod 250b having a predetermined length is formed at the lower end of the expansion part 250a, And the vertical expansion / contraction width of the elastic member 210 is determined.

 The support plate 230 is provided to completely seal the inner space of the bellows 210 from the pressure chamber 140. The support plate 230 is coupled to the lower end of the bellows 210, .

In the embodiment of the present invention, the lower end of the bellows 210 and the support plate 230 are welded at room temperature. The welding at room temperature is distinguished from the prior art, and is not a process performed in a vacuum chamber (vacuum chamber), so mass production is possible through automation. In addition, since the welding is performed at room temperature, the flowability of the melt is improved more than in a vacuum state, so that sealing between the bellows 210 and the support plate 230 can be ensured. As a result, the defect rate associated with sealing is reduced.

The sealing member 240 is a component for sealing the lower hole 232 of the support plate 230 so that the inner space formed by the bellows 210 and the support plate 230 coupled through the welding can be maintained in a vacuum state The sealing member 240 is coupled with the bottom hole 232 through the spot welding at a minimum welding amount when the combined body of the bellows 210 and the supporting plate 230 is placed in the vacuum chamber and the inner space thereof is in a vacuum state do.

The minimum amount of welding in this vacuum condition helps to minimize the hardening of the melt as well as the gas generated when the weld is melted. Therefore, rapid sealing of the sealing member 240 and the lower hole 232 through the spot welding not only keeps the inner space of the bellows 210 at a high-quality vacuum level, but also reduces the working time in a vacuum state, thereby reducing the cost .

In addition, if the degree of vacuum inside the bellows 210 is poor, the sealing member 240 and the bottom hole 232 can be spot-welded again in the vacuum chamber to correct defects, so that the vacuum degree can be easily managed, have.

The bellows assembly 200 formed through the above-described structure and process is inserted through the open upper end of the bellows casing 100 and is seated on the inner bottom surface of the bellows casing 100.

The set screw 300 is a component that hermetically closes the through hole 110 formed in the bellows casing 100 and supports the lower surface of the support plate 230. The upper surface of the set screw 300 is provided with the sealing member 240 The receiving groove 310 is formed to receive and fix the receiving groove 310. A third O-ring 330 is provided at the center of the O-ring to seal the space between the O-ring 110 and the pressure chamber 140. A thread corresponding to the thread is formed on the inner surface of the through hole 110 of the bellows casing 100 so that the set screw 300 can move up and down.

That is, the initial positions of the bellows assembly 200 and the valve stem 410, which are located at the upper portion and are in contact with each other, are adjusted according to the position of the set screw 300 adjusted up and down. Accordingly, the opening and closing degree of the valve varies depending on the position of the set screw 300. [

The valve housing 400 is a component having components for opening and closing between different ports (passages) which are functions of the control valve. The valve housing 400 is formed in an open top and bottom, The rods 410 are accommodated in the upper end of the bellows casing 100 and are coupled to each other. At this time, if the coupling between the bellows casing 100 and the valve housing 400 can be ensured, various coupling methods such as interference fit, welding or curling can be applied.

The valve housing 400 includes a valve stem 410, a second port 420, a second O-ring 430, a ball valve 440, a housing spring 450, a ball holding portion 460, .

The valve stem 410 is a component that moves in contact with the upper surface of the bellows 210 and moves together with the upward and downward expansion and contraction of the bellows 210. In accordance with the guide of the hollow 470 formed in the valve housing 400, And is brought into close contact.

The second port 420 is communicated with a crank chamber (not shown) of the compressor so that the crank pressure Pc acts on the second port 420. The second port 420 may be provided on the outer circumferential surface of the valve housing 400. In the embodiment of the present invention, the second port 420 is formed at an angle of 90 degrees along the outer circumferential surface of the cylindrical valve housing 400 so that a total of four second ports 420 are formed.

The second O-ring 430 made of a rubber material for packing is tightly fitted to the compressor in a state of being provided on the outer peripheral surfaces of the upper and lower ends of the valve housing 400 so that the pressure of the refrigerant gas in the compressor is completely 2 port 420 to the inner space of the valve housing 400.

The amount of opening and closing between the second port (420) communicating with the crank chamber of the compressor and the third port (468) communicating with the discharge chamber (not shown) of the compressor is controlled by moving up and down in contact with the upper end of the valve rod A housing spring 450 positioned at a lower end of the valve housing 400 to press the upper surface of the bellows 410 and a valve spring 450 positioned at an upper end of the ball valve 440, And a ball holding portion 460 for pressing the ball valve 440 to prevent the second port 420 and the third port 468 from communicating with each other unless they move upward.

The ball holding portion 460 includes a ball seat 462 which is positioned at the upper end of the ball valve 440 and supports the ball valve 440 and spherically contacted with the ball valve 440. One end of the ball seat 462 contacts the ball seat 462, A ball spring 464 which is brought into contact with the ball valve 466 to provide an elastic force to the ball valve 440 and a ball spring 464 which is positioned at the upper end of the ball spring 464 and is engaged with the upper end portion of the valve housing 400, And a spring support sheet 466 having a third port 468 which is a hole through which the discharge pressure Pd acts.

The filter unit 500 is a component to be coupled to the upper end of the valve housing 400. The filter unit 500 has a hole formed at one side of the outer circumferential surface thereof and a mesh network in the opened hole, So that foreign matter does not flow into the capacity type control valve 1.

Hereinafter, the operation of the variable capacity type control valve 1 according to the present invention will be described with reference to FIG.

The first port 120 formed in the bellows casing 100 is communicated with the suction chamber of the compressor so that the suction pressure Ps acts on the pressure chamber 140. At this time, when the suction pressure Ps is lower than the pressure in the sealed space of the bellows 210, the bellows 210 is expanded and contracted upward to move the ball valve 440 upward through the valve rod 410 do. A third port 468 which communicates with the discharge chamber of the compressor in accordance with the upward movement of the ball valve 440 and through which the discharge pressure Pd acts and a third port 468 which is in communication with the crank chamber of the compressor and in which the crank pressure Pc acts, The two ports 420 communicate with each other and the refrigerant gas flows in and out in the direction of the arrow in FIG.

Conversely, when the suction pressure Ps is higher than the pressure in the sealed space of the bellows 210, the bellows 210 contracts downward, which causes the ball valve 440 to move downward through the valve rod 410 do. As the ball valve 440 moves downward, the third port 468 and the second port 420 are shielded from each other to prevent the inflow and outflow of the refrigerant gas.

That is, the ball valve 440 is moved up and down by the expansion and contraction amount of the bellows 210 according to the magnitude of the suction pressure Ps acting on the pressure chamber 140 through the first port 120, The inflow amount and the outflow amount of the refrigerant are controlled.

The variable capacity type control valve 1 according to an embodiment of the present invention can be easily automated by welding the bellows 210 and the support plate 230 at room temperature and the flowability of the melt is improved, The sealing between the support plates 230 can be ensured, and the defect rate associated with the sealing can be reduced.

The bottom hole 232 of the support plate 230 and the sealing member 240 are spot-welded in the vacuum chamber to drastically reduce the amount of welding under a vacuum, so that the vacuum degree in the bellows 210 can be easily managed, maintained and maintained In addition, it is possible to reduce the working time in the vacuum state, thereby reducing the cost.

5 is a cross-sectional view of a variable capacity type control valve according to another embodiment of the present invention. 5, the variable capacity type control valve 1 according to another embodiment includes a bellows casing 100, a bellows assembly 200, a set screw 300, a valve housing 400, and a filter unit 500, And the like, and the description will be focused on a configuration different from the embodiment.

In the bellows casing 100 positioned at the lower end of the variable capacity type control valve 1 of the other embodiment, a hole communicating with the suction chamber of the compressor is not formed, and the first port 120a (120a) is formed on the outer circumferential surface of the valve housing 400, Is formed. The first port 120a is connected to the inner space of the bellows casing 100 via a hollow expansion part 470a formed at the lower end of the hollow 470 which receives the valve rod 410 and is guided by the up and down movement. Therefore, the suction pressure Ps of the compressor acts on the inner space of the bellows casing 100.

The lower end of the valve rod 410 is inserted into the depression 212 of the valve stem 410 and the valve stem 410 is inserted into the depression 210 of the valve stem 410, The opening and closing of the valve can be precisely controlled.

The valve housing 400 includes a valve rod 410 which moves upward and downward in a state of being closely contacted with the hollow 470 formed in the valve housing 400 and a valve rod 410 which moves upward and downward in contact with the upper end of the valve rod 410 and communicates with the crank chamber of the compressor. A ball valve 440 for regulating the amount of opening and closing between the two ports 420 and the third port 468 communicating with the discharge chamber of the compressor (not shown), and a ball valve 440 positioned at the upper end of the ball valve 440, A ball holding portion 460 that presses the ball valve 440 to prevent the second port 420 and the third port 468 from communicating with each other is provided.

The ball holding portion 460 includes a ball spring 464 having one end abutting against the ball valve 440 and the other end abutting against the spring support seat 466 to provide an elastic force to the ball valve 440, And a spring support sheet 466 which is coupled to the upper end of the valve housing 400 and has a third port 468, which is communicated with the discharge chamber of the compressor and through which the discharge pressure Pd acts, .

Meanwhile, the coupling between the bellows casing 100 and the valve housing 400 can be coupled in a curled manner in a state of being hermetically sealed by the O-ring 160.

In this case, the curling method is to form the end of the plate into a rounded shape. In addition to the safety, appearance, and reinforcement of the plate, it is a processing method having an advantage that a support tool can be inserted in a rounded shape.

The bellows casing 100 and the valve housing 400 are hermetically sealed by the O-ring 160 and then the protruding fastening part 150 formed in any one of the bellows casing 100 and the valve housing 400 ) By the curling method to manufacture the variable capacity type control valve 1. [

Since the coupling of the curling method is a simple mechanical assembly method rather than a welding by welding, the maintenance and repair of the manufacturing equipment is facilitated and the entire damage of the bellows casing 100 and the valve housing 400 during decomposition for repairing the product . Therefore, any one of the bellows casing 100 and the valve housing 400 can be reused, thereby helping maintenance and repair of the variable capacity type control valve 1. [

In addition, since the variable capacity type control valve 1 according to the present invention is a simple component assembly composed of a combination of the bellows casing 100 and the valve housing 400, the working time is reduced and the cost can be reduced .

Although the present invention has been described in connection with certain exemplary embodiments, it is to be understood that the invention is not limited to the disclosed exemplary embodiments. Therefore, the scope of the present invention should not be limited by the described embodiments, but should be defined by the appended claims and equivalents thereof.

1: variable capacity type control valve 10: welding
100: Bellows casing 110: Through hole
120: first port 130: first o-ring
140: pressure chamber 150:
160: O-ring 200: Bellows assembly
210: bellows 212: depression
220: coil spring 230: support plate
232: lower surface hole 240: sealing member
250: Stopper 300: Set screw
310: receiving groove 330: third o-ring
400: valve housing 410: valve stem
420: second port 430: second o-ring
440: Ball valve 450: Housing spring
460: ball portion 462: ball seat
464: Ball spring 466: Spring support sheet
468: Third port 470: hollow
470a: hollow extension part 500: filter part

Claims (5)

A bellows casing 100 formed with a through hole 110 on a lower surface thereof and an upper end opened;
A coil spring 220 disposed inside the bellows 210; a support plate 230 coupled to a lower end of the bellows 210; and a bellows 210 beneath the bellows 210, A bellows assembly 200 inserted through the open upper end of the casing 100;
A valve housing 400 accommodating a valve stem 410 provided at an upper end of the bellows 210 and coupled to an upper end of the bellows casing 100; And
The coupling between the bellows casing 100 and the valve housing 400 is hermetically sealed by an O-ring,
The supporting plate 230 is welded to the lower end of the bellows 210 at room temperature and a bottom hole 232 is formed and the sealing member 240 is spot welded to seal the bottom hole 232. The bellows 210, The inner space formed by the support plate 230 can be maintained in a vacuum state,
And a set screw (300) that hermetically closes the through hole (110) formed in the bellows casing (100) and supports the lower surface of the support plate (230)
The set screw (300)
A receiving groove 310 for receiving and fixing the sealing member 240 is formed on an upper surface thereof,
A third O-ring 330 is provided at the center of the bellows casing 100 to seal between the outside air connected to the through-hole 110 and the pressure chamber 140 inside the bellows casing 100,
And a screw thread is formed at the lower end of the bellows casing 100 so as to be screwed to the inner surface of the through hole 110 of the bellows casing 100 so that the set screw 300 can move up and down, The initial position of the assembly 200 and the valve stem 410 is adjusted so that the opening and closing degree of the valve is changed according to the position of the set screw 300,
The valve housing 400 is coupled to the upper end of the valve housing 400 and has an opening formed on one side of the outer circumference of the valve housing 400. A mesh network is formed in the opening, And a filter unit (500) for preventing a foreign matter from flowing into the filter unit (500).

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