JP6014709B2 - Automatic bidirectional expansion valve - Google Patents

Description

The present invention relates to an expansion valve belonging to the technical field of mechanical processing, and more particularly to an automatic bidirectional expansion valve.
Background art

The expansion valve is an important member in the refrigeration system and is installed between the condenser and the evaporator. The expansion valve boosts and liquefies the gas evaporated by the evaporator into a high-temperature and high-pressure liquid refrigerant by the compressor, and further throttles it to a low-temperature and low-pressure spray-like liquid refrigerant by the throttle port. As a result of absorption, the refrigeration effect is reached. The expansion valve controls the flow rate of the valve through a change in superheat at the end of the evaporator, so the flow rate becomes very small and the evaporator area cannot be fully used, or the flow rate becomes very large and the evaporator area is insufficient. This prevents the refrigerant from being completely vaporized and sucked into the compressor to form a liquid state.

There are many documents related to expansion valves. For example, the applicant of the present application has filed a patent application with the Chinese Patent Office whose application name is an expansion valve (application number 201210419218.1, publication number CN102878734A). The valve core I and the valve core II in the expansion valve are sealed by a conical surface. Specifically, the valve core I has a front throttle cone, and the valve core II has a front throttle cone suitable for the front throttle cone. Although this structure can realize sealing, the front drawing conical hole and the front drawing conical portion require high processing accuracy, so that a high precision device is required in the actual production process, and the product rate is low. Exists. As a result, there is a problem that the production cost of parts is high and the competitiveness in the product market is weak. Through the test, the expansion valve has a problem that the flow rate control system is low.

The object of the present invention is to provide an automatic bi-directional expansion valve for reducing the production cost of the valve core I and the valve core II against the above-mentioned problems existing in the prior art.

The object of the present invention is realized by the following technical method.
The automatic bidirectional expansion valve of the present invention includes a case, and a valve core I and a valve core II located in the case. The valve core II has a liquid passage small hole and a liquid passage large hole in series, and one end of the valve core I passes through the liquid passage large hole and is inserted into the liquid passage small hole. There is a liquid passage gap between one end of I and the side surface of the liquid passage small hole, and one end of the valve core I is a sealed conical surface that abuts against the angularity between the liquid passage small hole and the liquid passage large hole. It is characterized by having.

The liquid passage small hole and the liquid passage large hole of the valve core II in the automatic bidirectional expansion valve of the present invention are straight holes, and the axes overlap each other. Low requirements for machining liquid passage small holes, liquid passage large holes and closed conical surfaces, and the sealed conical surface and squares are sealed to reduce the requirements for machining accuracy, so the product pass rate can be efficiently increased. The production cost of parts can be further reduced. Preferably, an arc-shaped chamfer is processed at a cornering portion between the liquid passage small hole and the liquid passage large hole so that the arc chamfer is a burring in the cornering between the liquid passage small hole and the liquid passage large hole. Can be removed, and the adhesion between the angular core and the sealing conical surface can be increased, and further, the sealing performance between the valve core I and the valve core II can be ensured.

In the automatic bidirectional expansion valve, at the end portion of the valve core I, the space between the end surface from the sealed conical surface to the end portion is a large cylindrical portion and a small cylindrical portion. When valve core I or valve core II moves, if the conical conical surface moves away from the squareness between the liquid passage small hole and the liquid passage large hole, the magnitude of the expansion valve flow rate is large cylinder portion and liquid passage small. Controlled by the liquid passage gap between the side surfaces of the holes, small flow rate control is realized. If the large cylindrical part completely enters the liquid passage large hole, the magnitude of the expansion valve flow rate is controlled by the liquid passage gap between the small cylindrical part and the side surface of the liquid passage small hole, and the large flow rate is controlled. It has been realized.

In the automatic bidirectional expansion valve, at the end portion of the valve core I, the space between the end surface from the sealing conical surface to the end portion is a large cylindrical portion, a flow rate slow change portion, and a small cylindrical portion. Valve core I or valve core II moves, and if the sealing conical surface is separated from the squareness between the liquid passage small hole and the liquid passage large hole, the magnitude of the expansion valve flow rate is the large cylindrical portion and the liquid passage small hole. Control of the small flow rate is realized by the liquid passage gap between the side surfaces of the two. If the large cylindrical part completely enters the liquid passage large hole, the magnitude of the flow rate is controlled by the liquid passage gap between the flow rate slow change part and the side surface of the liquid passage small hole, and the variable control is realized. ing. If the flow rate slow change part completely enters the large liquid passage hole, the flow rate is controlled by the liquid passage gap between the small cylindrical part and the side surface of the small liquid passage hole. Is done.

In the automatic bidirectional expansion valve, a directional guide valve seat that is in solid contact with the case is provided outside the valve core I, and a first liquid passage hole is provided at the other end of the valve core I. A plurality of second liquid passage holes communicating with the first liquid passage hole are provided on the side wall of the wick I, and the small liquid passage hole penetrates the valve core II. Since the structure allows the medium to pass through the second liquid passage hole and the first liquid passage hole, the medium can flow along the circumferential direction of the case, and further, the medium is interposed between the casing and the case inlet. The problem that the structure due to passing through the outlet becomes complicated can be prevented, in other words, the structure may have no casing.

In the automatic bidirectional expansion valve, a first sealing washer is provided between the end face of the direction guide valve seat and the end face of the valve core II. The valve core II abuts the directional guide valve seat through the first sealing washer, and the slit between the valve core II and the directional guide valve seat, the slit between the directional guide valve seat and the case, and between the valve core II and the case. Prevents leakage or reflux of the medium in the slit, and further increases the control accuracy of the flow rate.

In the automatic bidirectional expansion valve, the valve core I has a sealing contact surface, and a second sealing washer is provided between the other end surface of the direction guide valve seat and the sealing contact surface of the valve core I. Yes. Since the sealing contact surface of the valve core I is contacted to the direction guiding valve seat through the second sealing washer, the slit between the sealing contact surface of the valve core I and the direction guiding valve seat, the direction guiding valve seat and the case This prevents leakage or recirculation of the medium in the slit between the valve core I and the slit between the valve core I and the case, and further increases the control accuracy of the flow rate.

Further, in order to protect the case, in the automatic bidirectional expansion valve, a protective cover is provided outside the case, both ends of the case are connecting pipe parts, and the connecting pipe parts are located outside the protective cover and are protected. The cover is fixed to the case.

In the automatic bidirectional expansion valve, at least two sealing grooves are provided on the outer surfaces of the valve core I and the valve core II, and a second ring seal that contacts the inner wall of the case is fitted in each sealing groove. Yes. The plurality of ring seals enhance the sealing performance and further improve the stability of the movement of the valve core, and in particular, can prevent the valve core from swinging.

In the automatic bi-directional expansion valve, a support post is fixed to both ends of the case, a liquid passage groove is provided on the corresponding side wall, and an auxiliary liquid passage penetrating radially in the inner end surface of the support post is provided. Grooves are provided. When the valve core and the inner end surface of the contact column come into contact, the auxiliary liquid passage groove ensures a smooth flow of the oil liquid, and the valve core is prevented by a negative pressure generated between the end surface of the valve core and the inner end surface of the contact column. The locking phenomenon can be prevented.

Compared to the prior art, the automatic bidirectional expansion valve of the present invention reduces the production cost of the valve core I and the valve core II by changing the sealing structure between the valve core I and the valve core II. Sealing between I and valve core II can be guaranteed. In the automatic bidirectional expansion valve of the present invention, the shape of the end of the valve core I is changed, and a first hermetic washer and a second hermetic washer are further added to efficiently increase the flow rate control accuracy.

FIG. 1 is a view showing a cross-sectional structure in Embodiment 1 of an automatic bidirectional expansion valve of the present invention. FIG. 2 is an enlarged view showing a partial structure of the portion A in FIG. FIG. 3 is an enlarged view showing a partial structure of a portion B in FIG. FIG. 4 is a view showing the inner end structure of the contact post of the automatic bidirectional expansion valve. FIG. 5 is a view showing a cross-sectional structure in Embodiment 2 of the automatic bidirectional expansion valve of the present invention. FIG. 6 is a view showing a cross-sectional structure in Embodiment 3 of the automatic bidirectional expansion valve of the present invention. FIG. 7 is an enlarged view showing a partial structure of a portion C in FIG. FIG. 8 is an enlarged view showing a partial structure of a portion D in FIG. FIG. 9 is a view showing a cross-sectional structure in Embodiment 4 of the automatic bidirectional expansion valve of the present invention.

The technical means of the present invention will be described in detail below with reference to specific embodiments and drawings of the present invention, but the present invention is not limited to these embodiments.

<Example 1>
As shown in FIG. 1, the automatic bidirectional expansion valve includes a case 1, a casing 2, a valve core I3, a valve core II4, a contact post 5, and a direction guide valve seat 6.

Case 1 is tubular, valve core I3, valve core II4, bearing post 5, spring, and direction guide valve seat 6 are located inside case 1, casing 2 is provided outside case 1 and casing 2 Both ends have connecting pipe portions.

The number of the contact pillars 5 is two, the two contact pillars 5 are respectively fixed to both ends of the case 1, and a liquid passage groove 5 a is provided on the side wall of the contact pillar 5. The valve core I3 and the valve core II4 are located between the two contact pillars 5, and two sealing grooves are provided on the outer surfaces of the valve core I3 and the valve core II4. A second ring seal 7 that is in contact with the inner wall is fitted. As a result, the valve core I3 and the valve core II4 slide along the inner wall of the case 1, and the space between the valve core I3 and the inner wall of the case 1 and between the valve core II4 and the inner wall of the case 1 are sealed.

The valve core II4 has a liquid passage small hole 4a and a liquid passage large hole 4b in series. The liquid passage small hole 4a and the liquid passage large hole 4b are provided along the axis of the valve core II4, respectively. 4a penetrates in the axial direction.

One end of the valve core I3 passes through the liquid passage large hole 4b and is inserted into the liquid passage small hole 4a, and one end of the valve core I3 is between the side surface of the liquid passage small hole 4a and the liquid passage A liquid passage gap is provided between the large holes 4b. One end of the valve core I3 has a sealed conical surface 3a that abuts against the angularity between the liquid passage small hole 4a and the liquid passage large hole 4b. When the sealing conical surface 3a moves away from the angularity between the liquid passage small hole 4a and the liquid passage large hole 4b, the medium flows from between the liquid passage small hole 4a and the liquid passage large hole 4b. A corner between the liquid passage small hole 4a and the liquid passage large hole 4b is an arc chamfer 4c.

The direction guide valve seat 6 is provided outside the valve core I3, the direction guide valve seat 6 is fixed to the case 1, and a first spring 8 is provided between the valve core I3 and the contact post 5. A second spring 9 is provided between the valve core II4 and the other contact post 5. As shown in FIG. 3, a first sealing washer 10 is provided between the end face of the direction guide valve seat 6 and the end face of the valve core II4. The first sealing washer 10 is in close contact with the case 1 and further guides the direction. It contacts the end face of the valve seat 6. As shown in FIG. 2, the valve core I3 has a sealing contact surface 3b, and a second sealing washer 11 is provided between the other end surface of the direction guide valve seat 6 and the sealing contact surface 3b of the valve core I3. The second sealing washer 11 is provided in close contact with the case 1 and further abuts against the other end face of the direction guide valve seat 6. As shown in FIG. 1, when the sealed conical surface 3a abuts against the angularity between the liquid passage small hole 4a and the liquid passage large hole 4b, the valve core II4 passes through the first sealing washer 10 to the direction guide valve seat 6. The sealing contact surface 3b of the valve core I3 and the second sealing washer 11 are in contact with each other.

Based on the actual elasticity of the first spring 8 and the second spring 9, the sealing contact surface 3b of the valve core I3 contacts the direction guide valve seat 6 through the second sealing washer 11, and the valve core II4 1 It is in a state of leaving through the sealing washer 10.

As shown in FIG. 7, at the end portion of the valve core I3, the space between the end surface from the sealing conical surface 3a to the end portion is a large cylindrical portion 3c and a small cylindrical portion 3d.
As shown in FIGS. 1 and 4, an auxiliary liquid passage groove 5b that penetrates in the radial direction is provided on the inner end surface of the contact post 5, and the auxiliary liquid passage groove 5b is provided to face the liquid passage small hole 4a. It has been.

As shown in FIG. 1, a spacer 12 is provided between the casing 2 and the case 1, and the spacer 12 and the case 1 are welded to each other. The spacer 12 is fixed to the casing 2, and the spacer 12 is provided with a third ring seal 13 that contacts the inner wall of the casing 2. The third ring seal 13 is a medium between the spacer 12 and the inner wall of the casing 2. Is prevented from leaking and affecting the flow control accuracy. The case 1 and the direction guide valve seat 6 are provided with a liquid passage port 1a. As shown in FIG. 1, when the pressure at the lower end of the casing 2 is larger than the pressure at the upper end, the valve core is caused by the pressure action of the medium. In order to move I3, the conical conical surface 3a is separated from the angularity between the liquid passage small hole 4a and the liquid passage large hole 4b, so that the medium passes through the liquid passage small hole 4a, the liquid passage large hole 4b, The passage between the liquid passage port 1a and the casing 2 and the case 1 can be flowed.

When the pressure at the lower end of the casing 2 is smaller than the pressure at the upper end, the sealed conical surface 3a moves between the liquid passage small hole 4a and the liquid passage large hole 4b to move the valve core II4 by the pressure action of the medium. Thus, the medium can flow through the passage between the casing 2 and the case 1, the liquid passage port 1a, the liquid passage large hole 4b, and the liquid passage small hole 4a.

<Example 2>
The present embodiment is almost the same as the structure and principle of the first embodiment, and the different points are as shown in FIG. 5, in the end portion of the valve core I3 between the end surface from the sealing conical surface 3a to the end portion. Is a large cylindrical part 3c, a flow rate slow change part 3e and a small cylindrical part 3d.

The other end face of the valve core I3 is provided with a first liquid passage hole 3f, and the side wall of the valve core I3 is provided with a second liquid passage hole 3g communicating with the first liquid passage hole 3f.
When the pressure at the lower end of the casing 2 is larger than the pressure at the upper end, the sealed conical surface 3a is moved between the liquid passage small hole 4a and the liquid passage large hole 4b to move the valve core I3 by the pressure action of the medium. Thus, the medium can flow through the small liquid passage hole 4a, the large liquid passage hole 4b, the second liquid passage hole 3g, and the first liquid passage hole 3f.

When the pressure at the lower end of the casing 2 is smaller than the pressure at the upper end, the sealed conical surface 3a moves between the liquid passage small hole 4a and the liquid passage large hole 4b to move the valve core II4 by the pressure action of the medium. Thus, the medium can flow through the first liquid passage hole 3f, the second liquid passage hole 3g, the liquid passage large hole 4b, and the liquid passage small hole 4a.

<Example 3>
The present embodiment is almost the same as the structure and principle of the second embodiment. The difference is that, as shown in FIG. 6, the outside of the case 1 does not have the casing 2 and the spacer 12, and both ends of the casing 2 are connected. It is extended as a pipe part.

<Example 4>
The present embodiment is almost the same as the structure and principle of the third embodiment. The difference is that the case 1 is provided with a protective cover 14 as shown in FIG. The both ends of the protective cover 14 are fixed to the case 1.
Since the third liquid passage hole that penetrates is provided at the center of the contact pillar 5, the medium passes through the third liquid passage hole.

1 case
1a Liquid passage port
2 Casing
3 Valve core I
3a Sealed conical surface
3b Sealing contact surface
3c Large cylindrical part
3d small cylinder
3e Flow rate slow change part
3f 1st liquid passage hole
3g 2nd liquid passage hole
4 Valve core II
4a Small hole for liquid passage
4b Large hole for liquid passage
4c Arc chamfer
5 Hit post
5a Liquid passage groove
5b Auxiliary liquid passage groove
5c 3rd liquid passage hole
6-way induction valve seat
7 Second ring seal
8 First spring
9 Second spring
10 First sealed washer
11 Second sealed washer
12 Spacer
13 Third ring seal
14 Protective cover
15 1st ring seal

Claims (10)

In an automatic bidirectional expansion valve including a case (1) and a valve core I (3) and a valve core II (4) located in the case (1)
The valve core II (4) has a liquid passage small hole (4a) and a liquid passage large hole (4b) in series,
One end of the valve core I (3) passes through the large liquid passage hole (4b) and is inserted into the small liquid passage hole (4a),
Between one end of the valve core I (3) and the side surface of the liquid passage small hole (4a), there is a liquid passage gap,
One end of the valve core I (3) has a sealed conical surface (3a) that abuts against the angularity between the liquid passage small hole (4a) and the liquid passage large hole (4b) ,
The liquid passage small hole (4a) and the liquid passage large hole (4b) are respectively provided along the axis of the valve core II (4), and the liquid passage small hole (4a) penetrates in the axial direction. Features an automatic bidirectional expansion valve. In an automatic bidirectional expansion valve including a case (1) and a valve core I (3) and a valve core II (4) located in the case (1)
The valve core II (4) has a liquid passage small hole (4a) and a liquid passage large hole (4b) in series,
One end of the valve core I (3) passes through the large liquid passage hole (4b) and is inserted into the small liquid passage hole (4a),
Between one end of the valve core I (3) and the side surface of the liquid passage small hole (4a), there is a liquid passage gap,
One end of the valve core I (3) has a sealed conical surface (3a) that abuts against the angularity between the liquid passage small hole (4a) and the liquid passage large hole (4b),
At both ends of the case (1), the contact pillars (5) are respectively fixed, and the side walls of the contact pillar (5) are provided with liquid passage grooves (5a), which are formed on the inner end surface of the contact pillar (5). Is provided with an auxiliary liquid passage groove (5b) penetrating in the radial direction,
An automatic bidirectional expansion valve characterized by that. The automatic bidirectional expansion valve according to claim 1 or 2 , characterized in that the angular tension between the liquid passage small hole (4a) and the liquid passage large hole (4b) is an arc chamfer (4c). The end portion of the valve core I (3) has a large cylindrical portion (3c) and a small cylindrical portion (3d) between the end faces from the sealed conical surface (3a) to the end portion. The automatic bidirectional expansion valve according to any one of claims 1 to 3 . At the end of the valve core I (3), there are a large cylindrical part (3c), a slow flow rate changing part (3e) and a small cylindrical part (3d) between the end face from the sealed conical surface (3a) to the end. 5. The automatic bidirectional expansion valve according to claim 4 , wherein A direction induction valve seat (6) is provided outside the valve core I (3), and the direction induction valve seat (6) is fixedly connected to the case (1).
The other end face of the valve core I (3) is provided with a first liquid passage hole (3f), and the side wall of the valve core I (3) has a plurality of second fluids communicating with the first liquid passage hole (3f). Liquid passage hole (3g) is provided,
The automatic bidirectional expansion valve according to any one of claims 1 to 5 , wherein the liquid passage small hole (4a) passes through the valve core II (4). The automatic sealing device according to claim 6 , wherein a first sealing washer (10) is provided between an end surface of the direction guide valve seat (6) and an end surface of the valve core II (4). Bidirectional expansion valve. The valve core I (3) has a sealing contact surface (3b) between the other end surface of the direction guide valve seat (6) and the sealing contact surface (3b) of the valve core I (3). 8. The automatic bidirectional expansion valve according to claim 7 , wherein a second hermetic washer (11) is provided. A protective cover (14) is provided on the outside of the case (1), and both ends of the case are connection pipe parts, and the connection pipe parts are located outside the protective cover (14). 9. The automatic bidirectional expansion valve according to any one of claims 1 to 8, wherein both ends of the valve and the case (1) are fixed to each other by welding. Each of the outer surfaces of the valve core I (3) and the valve core II (4) is provided with at least two sealing grooves, and a second ring seal that contacts the inner wall of the case (1) is provided in each sealing groove. The automatic bidirectional expansion valve according to any one of claims 1 to 9, wherein (7) is fitted.