JP2007100814A - Differential pressure regulating valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To compactly structure a differential pressure regulating valve and to quickly equalize pressure before and behind the valve after opening the valve. <P>SOLUTION: The differential pressure regulating valve 1 is equipped with a plug 3 in which a valve body forming part 21 having a function of a valve element of a first valve part, and a casing part 22 having a function of a case are integrally formed. The first valve part is opened/closed by the plug 3 proceeding/receding with respect to a housing 2. A coil spring 33 for closing the first valve part is arranged on the inside of the housing 2, and the plug 3 is structured in a substantially complementary shape to the housing 2 mounted so as to cover the housing 2. Further, when differential pressure in the opposite direction applied to the plug 3 after the first valve part is closed becomes a predetermined value or more, the valve body 28 deforms, a second valve part opens, reverse flow of a refrigerant is temporarily allowed, and the pressure before and behind the differential pressure regulating valve 1 is quickly equalized. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a differential pressure valve, and more particularly to a differential pressure valve suitable for use in a variable capacity compressor of an automotive air conditioner.

  The automotive air conditioner includes a refrigerant compression compressor that is driven by a vehicle engine as a power source. In this compressor, since the rotational speed of the vehicle engine greatly varies depending on the traveling state of the vehicle, it is necessary to maintain the discharge capacity at a set capacity regardless of the rotational speed. Therefore, a variable capacity compressor is used as a compressor of an automobile air conditioner.

  This variable capacity compressor is connected to the vehicle engine via an electromagnetic clutch, for example. When the automobile air conditioner is not in use, the electromagnetic clutch is disconnected so that the power of the vehicle engine is not transmitted to the variable capacity compressor. During use of the automobile air conditioner, the electromagnetic clutch is connected and variable. The capacity compressor is driven by the vehicle engine.

  However, providing such an electromagnetic clutch increases the weight of the vehicle and increases the manufacturing cost. Furthermore, large electric power is consumed when the electromagnetic clutch is operated. For this reason, so-called clutchless variable displacement compressors have been adopted in which the mounting of an electromagnetic clutch is eliminated and the vehicle engine is directly connected.

  Since this clutchless type variable displacement compressor is always driven to rotate by the vehicle engine, it is controlled to an operation state in which the discharge capacity is minimized, especially when the automobile air conditioner is not activated.

  However, even if the variable capacity compressor is controlled to the operation state with the minimum capacity, the discharge capacity is not zero. Therefore, the variable capacity compressor continues to discharge the refrigerant of the minimum capacity. For this reason, in the evaporator in which the refrigerant is continuously circulated in the refrigeration cycle and the refrigerant cooled from the expansion valve is fed, frost may adhere to the surface or freeze.

Therefore, in a clutchless type variable capacity compressor, a differential pressure valve is provided in a passage through which refrigerant is discharged from the discharge chamber (see, for example, Patent Document 1).
This differential pressure valve (expressed as “check valve” in Cited Document 1) has a valve body disposed downstream of the refrigerant flow with respect to the valve seat, and the valve body is urged in the valve closing direction by a spring. When the differential pressure across the valve reaches a predetermined value or more, the valve is opened and the refrigerant is discharged. That is, when the force acting in the valve opening direction due to the differential pressure acting on the valve portion of the differential pressure valve exceeds the load of the spring acting in the valve closing direction, the valve portion starts to open.

By disposing such a differential pressure valve in the variable capacity compressor, when the vehicle air conditioner is stopped and the variable capacity compressor is in the minimum capacity operation state, the valve portion is closed so that the refrigerant is not discharged, When the automotive air conditioner is activated, the valve is fully opened.
JP 2000-345967 A

  However, such a differential pressure valve has a refrigerant inlet port that communicates with the discharge port on one end side, a valve seat member provided with a valve seat on the other end side opening portion, and a case fitted to the valve seat member And a valve body that is slidable in the axial direction in the case, and a spring that biases the valve body in the direction of the valve seat member in the case, and has a large number of parts and a complicated structure. . For this reason, there exists a problem that manufacturing cost increases.

  In addition, since the valve body that operates in the axial direction and the spring that biases the valve body in the axial direction are arranged in series in the case, the case is enlarged in the axial direction. Further, since the case is arranged in series with the valve seat member in the axial direction, the entire differential pressure valve becomes larger in the axial direction, resulting in a problem of installation space in the variable capacity compressor.

  Further, when the automotive air conditioner is stopped and the differential pressure valve is closed, the differential pressure across the variable capacity compressor (the differential pressure (Pd−Ps) between the discharge pressure Pd and the suction pressure Ps) is reduced by the refrigerant in the expansion valve. It gradually becomes smaller and becomes equalized due to valve leakage. However, when this refrigerant passes through the gap of the valve portion of the expansion valve, a flow noise due to friction with the valve portion is generated, so that the longer the pressure equalization time, the more annoying the state will continue. become. For this reason, after the differential pressure valve is closed as described above, it is desirable that the differential pressure before and after the pressure be quickly reduced to equalize the pressure.

  The present invention has been made in view of such a problem, and an object thereof is to provide a differential pressure valve that can be realized in a compact and low-cost manner and that can quickly equalize the pressure before and after the valve is closed. To do.

  In the present invention, in order to solve the above problem, a differential pressure valve that opens and closes based on the differential pressure across the valve portion has a fluid inlet on one end and a valve seat formed near the outlet on the other end. A housing, a valve forming portion that is attached to and detached from the valve seat to open and close the first valve portion, a guide portion that slides in an opening and closing direction of the first valve portion along an outer peripheral surface of the housing, and A plug having an opening through which the fluid that has passed through the first valve portion is led out and an extending portion extending into the housing, the plug being attached to the housing so as to cover the other end; and the housing And an urging means for urging the plug in the valve closing direction via the extending portion, and a reverse applied to the plug after the first valve portion is closed. When the differential pressure in the direction exceeds a predetermined value, the plug is separated from the first valve portion. By opening formed valve bore, the differential pressure valve, characterized in that and a second valve portion to temporarily allow the reverse flow of the fluid.

  Such a differential pressure valve is attached to a housing in which a valve seat is provided so that a plug having the functions of a valve body and a case covers an end of the valve seat, and the opening and closing direction of the first valve portion To work. Further, an urging means is arranged inside the housing and urges the plug to be attracted to the housing side. Particularly when the valve is closed, the plug operates on the side close to the housing in the first valve portion.

  When the pressure inside the plug decreases after the first valve portion is closed and the differential pressure applied to the plug, that is, the differential pressure in the valve closing direction exceeds a predetermined value, the second valve portion opens. Thus, the backflow of the fluid is temporarily enabled.

According to the differential pressure valve of the present invention, the plug has the functions of the valve body and the case, the number of parts is reduced, and the structure is simplified, so that it can be realized at low cost.
Further, since the urging means is disposed inside the housing and the plug is attached so as to cover the end of the housing on the valve seat side, the differential pressure valve becomes compact in the axial direction.

  Furthermore, when the differential pressure in the reverse direction applied to the plug after the first valve portion is closed exceeds a predetermined value, the second valve portion is opened and the fluid backflow is temporarily allowed. It is possible to quickly equalize the pressure before and after the differential pressure valve after the first valve portion is closed.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
[First Embodiment]
First, a first embodiment of the present invention will be described. In the present embodiment, the differential pressure valve of the present invention is applied to a clutchless variable displacement compressor of an automotive air conditioner. FIG. 1 is a front view illustrating the configuration of the differential pressure valve according to the first embodiment. FIG. 2 is a cross-sectional view taken along the line AA of FIG.

  As shown in FIG. 1, the differential pressure valve 1 is constructed by coaxially assembling a stepped cylindrical housing 2 made of brass and a bottomed cylindrical plug 3 made of a resin material. The differential pressure valve 1 is disposed in a refrigerant passage connected to a discharge chamber of a variable capacity compressor.

  As shown in FIG. 2, the housing 2 is formed with an inlet 4 for communicating with the discharge chamber of the variable capacity compressor at one end thereof for introducing the discharged refrigerant, and leading the discharged refrigerant to the downstream side at the other end. A lead-out port 5 is formed. The housing 2 is configured such that the shape of the outer peripheral portion and the inner peripheral portion thereof decreases stepwise in the axial direction from the inlet 4 toward the outlet 5.

  That is, the housing 2 is provided with a flange portion 7 extending outwardly on the introduction port 4 side of the main body portion 6 in the center in the axial direction, and on the outlet port 5 side, the reduced diameter portion is gradually reduced in outer diameter. 8 and the valve seat formation part 9 are provided. This flange portion 7 is fixed to a refrigerant passage connected to a discharge chamber of a variable capacity compressor (not shown). Further, the valve seat 10 is constituted by the front end surface of the valve seat forming portion 9. Furthermore, a locking projection 11 for locking the movement of the plug 3 in the axial direction is provided at the end of the outer peripheral surface of the main body 6 on the reduced diameter portion 8 side.

  Further, the internal passage of the housing 2 is reduced in diameter by one step at a position slightly closer to the outlet 5 than the boundary between the main body 6 and the diameter-reduced portion 8, and the valve hole 12 (first Valve hole). A spring seat 13 is configured by a portion of the step portion of the internal passage facing the inlet 4 side.

  The plug 3 has a stepped cylindrical shape that is substantially complementary to the outer peripheral surface excluding the flange portion 7 of the housing 2 and is attached to the housing 2 so as to cover the outer peripheral surface from the outside. The plug 3 includes a bottomed cylindrical valve body forming portion 21 integrally formed by injection molding of a resin material, and a casing portion 22 having an enlarged diameter from the valve body forming portion 21 toward the opening end. Become.

  The valve body forming portion 21 has a valve forming portion 23 that opens and closes the first valve portion by attaching and detaching to the valve seat 10 by a portion facing the valve seat 10 at the bottom, that is, a ring-shaped region set at the bottom. It is configured. The inner peripheral surface of the valve body forming portion 21 is a guide portion 24 that slides in the axial direction along the outer peripheral surface of the reduced diameter portion 8 of the housing 2.

  Four openings 25 are provided at equal intervals in the circumferential direction at the corners of the bottom of the valve body forming portion 21 (see FIG. 1). The opening 25 opens from the peripheral edge of the bottom of the valve body forming portion 21 to the side, and guides the refrigerant that has passed through the valve to the downstream side.

  In the center of the bottom portion of the valve body forming portion 21, a shaft-like extension portion 26 extending in the axial direction is provided in the housing 2, and the bottom portion is disposed in the vicinity of the base end portion of the extension portion 26. Two valve holes 27 (second valve holes) penetrating in the direction are formed. Further, a valve body 28 and a stopper 29 are sequentially inserted from the side close to the valve hole 27 into the valve body forming portion 21. The valve body 28 constitutes a second valve portion together with the valve hole 27. The second valve portion opens when the reverse differential pressure applied to the plug 3 exceeds a predetermined value, but the valve opening pressure is higher than the valve closing pressure of the first valve portion. It is supposed to be.

  The valve body 28 has a disk-shaped main body made of rubber. The valve body 28 has a tapered shape in which the surface facing the valve hole 27 is inclined toward the valve hole 27 from the center toward the outer peripheral edge, and covers the valve hole 27 in a shape like an umbrella. It is configured. The valve hole 27 is closed by the peripheral edge of the valve body 28 coming into contact with the periphery of the valve hole 27 of the valve body forming portion 21. The material of the valve body 28 may be a material other than rubber as long as it is a member having flexibility and appropriate elastic force.

  The stopper 29 has a cylindrical main body made of a resin material. One end of the stopper 29 abuts on the end surface of the valve body 28 opposite to the valve hole 27, and a flange-shaped spring receiving portion 30 extending outward in the radial direction is formed at the other end. The spring receiving portion 30 is locked to a hook portion 31 provided at the tip of the extending portion 26. The material of the stopper 29 may be a metal such as stainless steel.

  The valve body 28 and the stopper 29 are inserted into the extending portion 26 from the tip and assembled. That is, a split groove 32 is formed at the distal end of the extending portion 26 so as to be elastically deformable in the radial direction. When the valve body 28 and the stopper 29 are inserted through the extending portion 26, the distal ends of the valve body 28 and the stopper 29 are pressed and elastically deformed so as to sandwich the dividing groove 32, and the valve body 28 and the stopper 29 are reduced in the radial direction and then inserted. When the insertion is completed and the pressing force is released, the split groove 32 is elastically restored to its original shape. At this time, the valve body 28 and the stopper 29 are fixed so as to be sandwiched between the bottom part of the valve body forming part 21 and the hook part 31 of the extension part 26. Further, since the valve body 28 is pressed toward the valve hole 27 by the stopper 29, the peripheral end edge of the valve body 28 is in close contact with the bottom of the valve body forming portion 21 with an appropriate surface pressure.

  Between the spring receiving portion 30 and the spring seat 13, a conical coil spring 33 (“biasing means”) that biases the plug 3 toward the housing 2, that is, the valve closing direction of the first valve portion. Is applicable). As shown in the figure, the length of the extending portion 26 is set so that it is located in the vicinity of the inlet 4 of the housing 2 and does not protrude outside from the housing 2 when the first valve portion is in the closed state. Has been.

  The casing portion 22 is connected to the guide portion 24 of the valve body forming portion 21 and extends outward in the radial direction, and extends from the outer peripheral end in the axial direction so as to cover the main body portion 6. It consists of a cylindrical body having an L-shaped cross section provided with a restricting portion 37.

  The base portion 36 faces the end surface of the main body portion 6, and a damper chamber 38 is configured by a space formed between these facing surfaces. The damper chamber 38 prevents fine vibration in the axial direction of the plug 3. A minute pressure relief hole 39 that allows the damper chamber 38 to communicate with the outside is provided in the peripheral edge of the base portion 36.

  In addition, a locking protrusion 40 that protrudes inward in the radial direction is provided around the opening end of the restriction portion 37, and faces the locking protrusion 11 of the housing 2 in the axial direction. When the plug 3 operates in the valve opening direction, the movement of the plug 3 is restricted by the locking protrusion 40 being locked to the locking protrusion 11. That is, the locking projection 40 and the locking projection 11 constitute a restricting structure that locks the sliding of the plug 3 when the valve portion is fully opened and restricts the lift amount of the valve forming portion 23 from the valve seat 10. Yes.

  Next, the operation of the differential pressure valve of the present embodiment will be described. FIG. 3 is a cross-sectional view showing a state in which the first valve portion of the differential pressure valve is opened. FIG. 4 is a cross-sectional view illustrating a state in which the second valve portion of the differential pressure valve is opened.

  When the variable capacity compressor is in the minimum capacity operation state and the discharge pressure is small, such as when the automotive air conditioner is steadily stopped, the differential pressure valve 1 is a coil as shown in FIG. The valve forming portion 23 is seated on the valve seat 10 by the load of the spring 33, and the first valve portion is closed. Moreover, since it is a steady state, the 2nd valve part will be in a valve closing state.

  When the automobile air conditioner is started or when the variable capacity compressor is shifted from the minimum capacity operation to the variable capacity operation, the valve opening direction force due to the differential pressure across the differential pressure valve 1 is closed by the load of the coil spring 33. When the force is exceeded, the first valve portion starts to open. At this time, the valve forming portion 23 is lifted from the valve seat 10 and eventually enters the fully open state shown in FIG. The valve opening degree of the first valve portion when fully opened is set in advance by the restriction structure formed by the locking projection 40 and the locking projection 11.

  Then, when the automotive air conditioner is stopped and the variable capacity compressor shifts to the minimum capacity operation state, the differential pressure across the differential pressure valve 1 decreases, and the first valve portion is closed as shown in FIG. It becomes. When the discharge pressure of the variable capacity compressor is further reduced, the reverse pressure of the differential pressure valve 1 (pressure in the direction of closing the first valve portion) is relatively increased. That is, when the differential pressure in the reverse direction applied to the plug 3 is increased and exceeds a predetermined value, the valve hole 27 is deformed so that the outer peripheral edge of the valve body 28 is turned up (so that the umbrella shape is further opened). It opens and the second valve part opens. When the refrigerant on the downstream side of the differential pressure valve 1 flows backward through the valve hole 27 and the pressure before and after the differential pressure valve 1 is equalized, the differential pressure in the reverse direction to the plug 3 is reduced. The shape of the body 28 is elastically restored, the second valve portion is closed, and the state shown in FIG. 2 is obtained.

  As described above, the differential pressure valve 1 is a plug in which the valve body forming portion 21 having the function of the valve body of the first valve portion that is the main valve and the casing portion 22 having the function of the case are integrally formed. 3 is provided. The plug 3 moves forward and backward with respect to the housing 2 to open and close the first valve portion. For this reason, the number of parts is reduced and the structure is simplified, so that it can be realized at low cost.

  In addition, a coil spring 33 for closing the first valve portion is disposed inside the housing 2, and the plug 3 is configured so as to be substantially complementary to the housing 2 so as to cover the housing 2. The pressure valve 1 becomes compact in the axial direction. In particular, when the first valve portion is closed, the plug 3 is substantially engaged with the housing 2, while the extending portion 26 that supports the coil spring 33 is configured not to protrude outside the housing 2. Therefore, the differential pressure valve 1 becomes very compact. For this reason, it is convenient for installation in the variable capacity compressor of the automotive air conditioner.

  Furthermore, if the reverse differential pressure applied to the plug 3 after the first valve portion is closed becomes equal to or greater than a predetermined value, the second valve portion opens and the refrigerant backflow is temporarily allowed. The pressure before and after the differential pressure valve 1 after the first valve portion is closed can be quickly equalized. That is, when the differential pressure valve 1 is installed in the refrigeration cycle of an automotive air conditioner, the pressure difference between the pressure before and after the variable capacity compressor (that is, the pressure before and after the expansion valve) is positively and promptly increased by the differential pressure valve 1. Done. As a result, the leakage of the refrigerant at the expansion valve is suppressed, thereby preventing or suppressing the generation of flow noise.

[Second Embodiment]
Next, a second embodiment of the present invention will be described. The differential pressure valve according to the present embodiment is substantially the same as the configuration of the differential pressure valve according to the first embodiment except for the difference in the structure of the plug. The description is omitted. FIG. 5 is a front view illustrating the configuration of the differential pressure valve according to the second embodiment. 6 is a cross-sectional view taken along line BB in FIG. FIG. 7 is a cross-sectional view illustrating a state in which the first valve portion of the differential pressure valve is opened. FIG. 8 is a cross-sectional view showing a state where the second valve portion of the differential pressure valve is opened.

  As shown in FIG. 5, the differential pressure valve 201 is configured by coaxially assembling a stepped cylindrical housing 2 made of brass and a bottomed cylindrical plug 203 made of a resin material.

  As shown in FIG. 6, the plug 203 is provided with four openings 225 at equal intervals in the circumferential direction in the vicinity of the periphery of the bottom of the valve body forming portion 221. The opening 225 does not open in the side part of the valve body forming part 221 and is formed so as to penetrate the bottom part in the axial direction (that is, the opening and closing direction of the first valve part).

  As shown in FIG. 6, when the variable capacity compressor is in the minimum capacity operation state and the discharge pressure is small, such as when the automotive air conditioner is steadily stopped, the differential pressure valve 201 The valve forming portion 23 is seated on the valve seat 10 by the load of the coil spring 33, and the first valve portion is closed. Further, the second valve portion is also closed.

  When the automotive air conditioner is started or when the variable capacity compressor is shifted from the minimum capacity operation to the variable capacity operation, the valve opening direction force due to the differential pressure across the differential pressure valve 201 is closed by the load of the coil spring 33. When the force is exceeded, the first valve portion starts to open. At this time, the valve formation part 23 lifts from the valve seat 10, and eventually becomes a fully open state shown in FIG. At this time, the refrigerant introduced from the introduction port 4 is led out to the downstream side in the axial direction through the opening 225.

  Then, when the automotive air conditioner is stopped and the variable capacity compressor shifts to the minimum capacity operation state, the differential pressure across the differential pressure valve 201 decreases, and the first valve portion is closed as shown in FIG. It becomes. When the discharge pressure of the variable capacity compressor further decreases and the differential pressure in the reverse direction applied to the plug 203 exceeds a predetermined value, the valve element 28 is deformed to open the valve hole 27, and the second valve The part opens. Then, when the refrigerant on the downstream side of the differential pressure valve 201 flows backward through the valve hole 27 and the pressure before and after the differential pressure valve 201 is equalized, the second valve portion is closed and shown in FIG. It becomes a state.

  Also in the differential pressure valve 201 of the present embodiment, the plug 203 has the functions of the valve body and the case of the first valve portion, the number of parts is reduced, and the structure is simplified, so that it is realized at low cost. be able to.

Further, since the coil spring 33 is disposed inside the housing 2 and the plug 203 is attached so as to cover the housing 2, the coil spring 33 is compact in the axial direction.
Furthermore, if the reverse differential pressure applied to the plug 203 after the first valve portion is closed exceeds a predetermined value, the second valve portion opens and the refrigerant backflow is temporarily allowed. The pressure before and after the differential pressure valve 201 can be quickly equalized. That is, when the differential pressure valve 201 is installed in the refrigeration cycle of the automotive air conditioner, the leakage of the refrigerant at the expansion valve is suppressed, and the generation of the flow noise caused thereby can be prevented or suppressed.

[Third Embodiment]
Next, a third embodiment of the present invention will be described. The differential pressure valve according to the present embodiment is substantially the same as the configuration of the differential pressure valve of the first embodiment except that the structure of the plug is mainly different. A description thereof will be omitted, for example. FIG. 9 is a front view illustrating the configuration of the differential pressure valve according to the third embodiment. 10 is a cross-sectional view taken along the line CC of FIG. FIG. 11 is a cross-sectional view showing the configuration of the differential pressure valve in the opened state. Further, FIG. 12 is a cross-sectional view showing a state in which the second valve portion of the differential pressure valve is opened.

  As shown in FIG. 9, the differential pressure valve 301 is configured by coaxially assembling a stepped cylindrical housing 302 made of brass and a bottomed cylindrical plug 303 made of a resin material.

  As shown in FIGS. 10 to 12, the housing 302 has substantially the same configuration as the housing 2 of the first embodiment, but the main body 306, in relation to the shape of the plug 303 having a complementary shape, The reduced diameter portion 308 and the valve seat forming portion 309 are configured to be slightly longer in the axial direction.

  The valve body forming portion 321 of the plug 303 constitutes a valve forming portion 23 that is attached to and detached from the valve seat 10 to open and close the first valve portion by a ring-shaped region facing the valve seat 10 at the bottom. From the vicinity of the outer periphery of the valve forming portion 23, a pressure receiving holding portion 310 is extended so as to be extrapolated to the valve seat forming portion 309. Six openings 325 are provided at equal intervals in the circumferential direction at the corners of the bottom of the valve body forming portion 321 (see FIG. 9). The opening 325 opens from the periphery of the bottom of the valve body forming part 321 to the side, and guides the refrigerant that has passed through the first valve part to the downstream side.

FIG. 13 is a cross-sectional view illustrating the configuration of the plug. 14 is a view taken in the direction of arrow E in FIG.
As shown in these drawings, the pressure receiving holding portion 310 extends from the bottom portion of the plug 303 like a wall portion surrounding the proximal end portion of the extending portion 26 and the valve hole 27. On the side surface of the pressure receiving holding portion 310, cutout portions 311 cut out as tapered concave portions are provided at equal intervals (every 30 degrees) in the circumferential direction. As will be described later, the notch 311 forms a throttle channel for the refrigerant when the first valve is opened.

  That is, as shown in FIG. 11, the pressure receiving diameter when the valve is closed (the diameter of the region receiving the refrigerant pressure from the upstream side) is φA, and the pressure receiving diameter changes to φB (> φA) when the valve is opened. To do. Therefore, when the first valve portion starts to open, the pressure receiving diameter increases and the load in the valve opening direction received by the plug 303 increases. Further, when the first valve portion starts to open, a trapezoidal throttle channel is formed between the notch portion 311 and the valve seat forming portion 309 described above, and therefore, as shown by the arrows in the figure, the upstream side The refrigerant from is passed through this throttle channel to the downstream side. At this time, the throttle passage gradually increases as the valve forming portion 23 lifts from the valve seat 10, so that the pressure receiving diameter φB is maintained. That is, when the valve forming portion 23 and the valve seat 10 are simply in contact with each other when the valve is closed as in the first embodiment, the valve forming portion 23 is lifted from the valve seat 10 when the valve is opened. The pressure receiving diameter tends to be small. However, the pressure can be held by providing the pressure receiving holding portion 310 around the first valve portion as in the present embodiment, and the change in the pressure receiving diameter can be reduced. That is, the load in the valve opening direction received by the plug 303 can be kept large regardless of the stroke of the first valve portion, and the first valve portion can be quickly opened.

In the present embodiment, the shape of the cutout portion 311 is set so that the throttle channel has a trapezoidal shape, but it may be set to have a triangular shape or other shapes.
[Fourth Embodiment]
Next, a fourth embodiment of the present invention will be described. The differential pressure valve according to the present embodiment is substantially the same as the configuration of the differential pressure valve of the third embodiment except that the structure of the plug is different. Therefore, the same reference numerals are assigned to substantially the same components. Therefore, the description is omitted. FIG. 15 is a front view illustrating the configuration of the differential pressure valve according to the fourth embodiment. 16 is a cross-sectional view taken along the line DD in FIG. FIG. 17 is a cross-sectional view showing a state in which the first valve portion of the differential pressure valve is opened. FIG. 18 is a cross-sectional view showing a state where the second valve portion of the differential pressure valve is opened.

  As shown in FIG. 15, the differential pressure valve 401 is configured by coaxially assembling a stepped cylindrical housing 302 made of brass and a bottomed cylindrical plug 403 made of a resin material.

  As shown in FIGS. 16 to 18, the plug 403 is provided with six openings 425 at equal intervals in the circumferential direction in the vicinity of the periphery of the bottom of the valve body forming portion 421. The opening 425 does not open in the side part of the valve body forming part 421 and is formed so as to penetrate the bottom part in the axial direction (that is, the opening / closing direction of the first valve part). For this reason, when the first valve portion is opened, the refrigerant introduced from the inlet 4 is led to the downstream side in the axial direction through the opening 425.

  In each of the above embodiments, an example in which a conical coil spring is provided as an urging means for pulling the plug into the housing side has been described. However, a coil spring having a shape other than a conical shape may be used. Other urging means may be used as long as it can be urged.

  Moreover, although the example which applied this invention to the differential pressure | voltage valve installed in the variable capacity compressor of the clutchless system of an automotive air conditioner was shown, the use is not restricted to this, The fluid which regulates the flow of fluid to one direction Any differential pressure valve arranged in the passage is applicable.

It is a front view showing the structure of the differential pressure valve which concerns on 1st Embodiment. It is AA arrow sectional drawing of FIG. It is sectional drawing showing the state which the 1st valve part of the differential pressure valve opened. It is sectional drawing showing the state which the 2nd valve part of the differential pressure | voltage valve opened. It is a front view showing the structure of the differential pressure valve which concerns on 2nd Embodiment. It is BB arrow sectional drawing of FIG. It is sectional drawing showing the state which the 1st valve part of the differential pressure valve opened. It is sectional drawing showing the state which the 2nd valve part of the differential pressure | voltage valve opened. It is a front view showing the structure of the differential pressure valve which concerns on 3rd Embodiment. It is CC sectional view taken on the line of FIG. It is sectional drawing showing the structure of the differential pressure | voltage valve in the valve opening state. It is sectional drawing showing the state which the 2nd valve part of the differential pressure | voltage valve opened. It is sectional drawing showing the structure of a plug. FIG. 14 is a view taken in the direction of arrow E in FIG. 13. It is a front view showing the structure of the differential pressure | voltage valve which concerns on 4th Embodiment. It is DD sectional view taken on the line of FIG. It is sectional drawing showing the state which the 1st valve part of the differential pressure valve opened. It is sectional drawing showing the state which the 2nd valve part of the differential pressure | voltage valve opened.

Explanation of symbols

1,201,301,401 Differential pressure valve 2,302 Housing 3,203,303,403 Plug 4 Inlet 5 Outlet 10 Valve seat 12,27 Valve hole 21,221, 321,421 Valve body forming part 22 Casing part 23 Valve forming portion 24 Guide portion 25, 225, 325, 425 Opening portion 26 Extension portion 28 Valve element 29 Stopper 38 Damper chamber 310 Pressure receiving holding portion 311 Notch portion

Claims (18)

In the differential pressure valve that opens and closes based on the differential pressure across the valve,
A housing having a fluid inlet on one end and a valve seat formed near the outlet on the other end;
A valve forming part that opens and closes the first valve part by attaching and detaching to the valve seat; a guide part that slides in an opening and closing direction of the first valve part along an outer peripheral surface of the housing; and the first valve A plug having an opening for leading the fluid that has passed through the portion and an extending portion extending into the housing, and attached to the housing so as to cover the other end side;
A biasing means disposed in the housing and biasing the plug in the valve closing direction via the extension;
When the differential pressure in the reverse direction applied to the plug becomes a predetermined value or more after the first valve portion is closed, the plug is formed separately from the first valve portion. A second valve portion for opening the valve hole to temporarily allow back flow of the fluid;
A differential pressure valve characterized by comprising:   The second valve portion includes a valve body that is supported by the extension portion and that is arranged to be able to open and close the valve hole by being attached to and detached from the valve hole or the periphery thereof from the inside of the plug. The differential pressure valve according to claim 1, wherein   The differential pressure valve according to claim 2, wherein the valve body is configured by a flexible member that is deformed in a valve opening direction when the differential pressure in the reverse direction becomes equal to or greater than the predetermined value. The valve body is supported by being extrapolated to the extension part,
The differential pressure valve according to claim 3, wherein a stopper for preventing movement of the valve body in the valve opening direction is disposed between the valve body and the extending portion. The stopper is composed of a cylindrical member extrapolated to the extension part,
The biasing means is formed of a coil spring, and is arranged such that one end thereof is supported by the housing and the other end is supported by an end portion of the stopper opposite to the valve body. Item 5. The differential pressure valve according to Item 4.   The said valve hole was formed so that the said plug might be penetrated in the axial direction of the said extension part in the 1 or several position vicinity of the base end part of the said extension part. Differential pressure valve. The valve seat is configured from a tip surface on the other end side of the housing,
The valve forming portion is configured from a portion of the plug facing the valve seat;
The differential pressure valve according to claim 1.   The opening is provided at a position outside the first valve portion in the plug, and includes one or a plurality of holes penetrating the plug in the opening / closing direction of the first valve portion. The differential pressure valve according to claim 1. The housing has a stepped cylindrical shape whose outer diameter decreases toward the other end side, while the plug has a stepped cylindrical shape whose inner diameter increases toward the opening end thereof,
Between the outer peripheral surface of the housing and the inner peripheral surface of the plug, when the first valve portion is fully opened, the sliding of the plug is locked, so that the lift amount from the valve seat of the valve forming portion is increased. A regulatory structure to regulate,
The differential pressure valve according to claim 1.   The plug is configured such that a portion excluding the extension portion is substantially complementary to the outer peripheral surface on the other end side of the housing, and is substantially fitted with the housing when the valve is closed. The differential pressure valve according to claim 1.   The differential pressure valve according to claim 1, wherein the extension portion is configured to have a length that does not protrude outside the housing even when the valve is closed.   The differential pressure valve according to claim 10, wherein a damper chamber is configured by a space portion formed between an outer peripheral surface of the housing and an inner peripheral surface of the plug.   The differential pressure valve according to claim 1, wherein the valve forming portion, the guide portion, the opening portion, and the extending portion of the plug are integrally formed of a resin material.   2. The differential pressure valve according to claim 1, wherein the differential pressure valve is arranged in a refrigerant passage connected to a discharge chamber of a variable capacity compressor of an air conditioner for an automobile and controls a flow of the refrigerant as the fluid.   The pressure receiving holding part which suppresses the reduction | decrease of the pressure receiving diameter of the part which receives the load of a valve opening direction in the said plug when the said valve formation part lifts from the said valve seat is provided. Differential pressure valve.   The differential pressure valve according to claim 15, wherein the pressure receiving holding portion is configured such that the pressure receiving diameter is larger when the valve is opened than when the valve is closed.   The differential pressure valve according to claim 16, wherein the pressure receiving holding portion includes a wall portion extending from the valve forming portion of the plug and surrounding the other end portion of the housing including the valve seat.   18. The differential pressure valve according to claim 17, wherein the wall portion is formed with a notch portion that forms a throttle channel for the fluid with the other end portion of the housing when the valve is opened.

Images