JP4663575B2 - Control valve, variable capacity compressor and refrigeration cycle apparatus - Google Patents

Description

  The present invention relates to a control valve, a variable capacity compressor, and a refrigeration cycle apparatus, and more particularly, includes a control valve used as a capacity control valve of a variable capacity compressor, a variable capacity compressor, and a variable capacity compressor. The present invention relates to a refrigeration cycle apparatus used for an air conditioner for an automobile.

  In a refrigeration cycle apparatus used in an in-vehicle air conditioner or the like, a swash plate type variable capacity compressor is often used as an engine-driven compressor. In the variable capacity compressor of the swash plate type, the discharge capacity quantitatively changes according to the internal pressure (crank chamber pressure) of the crank chamber in which the swash plate is accommodated. That is, as the crank chamber pressure increases, the swash plate inclination angle decreases and the discharge capacity decreases. Conversely, as the crank chamber pressure decreases, the swash plate inclination angle increases and the discharge capacity increases. To do. The discharge capacity can be controlled in a feedback compensation manner by detecting the discharge capacity (discharge flow rate) and controlling the crank chamber pressure with a control valve in accordance with the detected discharge capacity.

As a capacity control valve for controlling the discharge capacity of such a variable capacity compressor, the pressure difference between the two positions separated by a predetermined amount between the upstream side and the downstream side of the discharge path of the variable capacity compressor (the discharge path Using the fact that the pressure difference between the upstream and downstream sides of the throttle part provided in the middle shows a positive correlation with the pressure loss corresponding to the discharge flow rate, this pressure difference is expressed by a pressure-sensitive member (pressure-sensitive plate). A differential pressure sensing type capacity control valve that senses and controls the pressure in the crank chamber according to the discharge capacity is known (for example, Patent Documents 1 and 2).
JP 2002-285958 A JP 2004-324882 A

The correlation between the flow rate of the flow rate sensing fluid (discharge flow rate) and the generated differential pressure is expressed by the following equation (1) by Bernoulli's theorem V = √ (2ΔP / ρ).
Q = Af · V = Af · Ca√ (2ΔP / ρ) (1)
Where Q: flow rate of the flow sensing fluid, Af: flow path cross-sectional area, V: flow velocity, ΔP: differential pressure, ρ: density, Ca: proportional constant.

Considering the correlation between the differential pressure ΔP and the generated load W caused by the pressure sensitive plate, the generated load W is theoretically expressed as W = Ap · ΔP, where Ap is the pressure receiving area. Since the differential pressure ΔP is proportional to the square of the flow rate Q, the generated load W is expressed by the following equation (2) in consideration of the proportionality constant Cb.
W = Ap · ΔP = Cb · Ap · Q ² (2)

  Therefore, the generated load W is proportional to the square of the flow rate Q, and the Q-W characteristic line becomes a quadratic curve as indicated by the symbol A in FIG. The rate of change of the load W becomes large, and it is not possible to obtain a large control allowable range showing approximate linearity with respect to Q-W.

  On the other hand, when the rate of change of the generated load W with respect to the flow rate Q is constant, as shown by the symbol B in FIG. 12, the QW characteristic line shows approximate linearity with respect to the QW characteristic. A large control allowable range can be taken. Further, the change width of the generated load W can be reduced, and the change width of the flow rate Q with respect to a certain generated load change width can be increased.

  The problem to be solved by the present invention is to suppress the change in the rate of change of the generated load with respect to the flow rate of the flow rate sensing fluid, thereby allowing a large control allowable range showing approximate linearity with respect to the flow rate-generated load characteristic. In other words, the change width of the generated load can be reduced, or the change width of the flow rate with respect to the generated load change width can be increased.

  According to a first aspect of the present invention, there is provided a control valve comprising: a valve body that controls a flow rate by changing an opening degree of a valve port by movement in a valve shaft direction in a valve chamber formed in a valve housing; and a valve shaft of the valve body A pressure receiving plate attached to the valve portion, and the pressure receiving plate defines a throttle portion between the valve chamber wall and a pressure upstream of the throttle portion generated by fluid flowing through the throttle portion. And a downstream pressure, and a control valve that drives the valve body in the valve axial direction by a load generated by the differential pressure, the pressure receiving plate is made of an elastic material, and the pressure receiving plate is Elastically deforms as the differential pressure increases, reducing the effective pressure receiving area.

  In the control valve according to a second aspect of the present invention, the pressure receiving plate further reduces the effective pressure receiving area by elastic deformation according to the increase in the differential pressure, and increases the passage sectional area of the throttle portion.

  In a control valve according to a third aspect of the present invention, preferably, the pressure receiving plate is constituted by a leaf spring in which a slit is formed in the middle of the radial direction from the radial outer edge.

  The control valve according to a fourth aspect of the present invention is preferably configured such that the differential pressure also acts on the valve stem itself.

  The control valve according to the invention described in claim 5 preferably has spring means for urging the valve body in a direction opposite to the driving direction of the valve body by the pressure receiving plate.

  The control valve according to the invention described in claim 6 is preferably an electromagnetic means for urging the valve body in a direction opposite to the driving direction by the pressure receiving plate by electromagnetic force, and the driving direction of the valve body by the pressure receiving plate. And spring means for urging the valve body in the same direction.

  A control valve according to a seventh aspect of the invention is used as a capacity control valve of a variable capacity compressor that quantitatively changes a discharge capacity in accordance with a control valve crank chamber pressure, and a discharge flow path of the variable capacity compressor. The fluid flowing through the valve chamber is introduced into the valve chamber, and the pressure receiving plate drives the valve body in the valve opening direction by the differential pressure generated between the upstream side and the downstream side of the throttle passage according to the flow rate of the fluid, The valve body controls the flow rate of the fluid flowing from the discharge passage to the crank chamber.

  A variable displacement compressor according to an eighth aspect of the invention is a variable displacement compressor that quantitatively changes the discharge capacity in accordance with the crank chamber pressure, and is charged to a valve mounting bore formed in the compressor body. The control valve according to the invention of item 7 is inserted and mounted.

  A refrigeration cycle apparatus according to a ninth aspect of the invention has a variable capacity compressor, a condenser, an expansion means, an evaporator, and a refrigerant passage that connects these in a loop, according to the seventh aspect of the invention. Includes control valve.

  According to the control valve according to the present invention, the capacity variable compressor having the same, and the refrigeration cycle apparatus having the capacity variable compressor, the control valve responds to an increase in the differential pressure, that is, in the valve chamber. As the pressure sensing plate elastically deforms as the flow rate of the flow sensing fluid flowing through the restrictor increases, the effective pressure receiving area of the pressure sensing plate decreases, so the rate of change of the generated load relative to the flow rate in the large flow rate region is Compared to this, the increase is reduced, and the change in the change rate of the generated load with respect to the flow rate can be suppressed.

  As a result, it is possible to increase a control allowable range indicating approximate linearity with respect to the flow rate-generated load characteristic, to reduce the change width of the generated load, or to increase the change width of the flow rate with respect to the generated load change width. become.

  Embodiment 1 of a control valve according to the present invention will be described with reference to FIG.

  The control valve of the present embodiment is generally indicated by reference numeral 10. The control valve 10 has a valve housing 11. The valve housing 11 has a cup shape with an upper opening, and cooperates with a valve rod guide member 12 fixedly attached to an edge of the upper opening to define a cylindrical chamber-like valve chamber 13.

  The valve housing 11 is formed with a flow sensing fluid inlet port 14 that opens in the lower region of the valve chamber 13, and the valve rod guide member 12 is formed with a flow sensing fluid outlet port 15 that opens in the upper region of the valve chamber 13. . The flow rate sensing fluid flows into the valve chamber 13 from the flow rate sensing fluid inlet port 14. The flow rate sensing fluid flows from the lower side to the upper side in the valve chamber 13 and flows out of the valve chamber 13 from the flow rate sensing fluid outlet port 15.

  The valve housing 11 is formed with a valve port 16 that opens to the lower bottom of the valve chamber 13 and a flow rate control fluid outlet port 17 that communicates with the valve port 16 on the opposite side of the valve chamber 13.

  A valve rod 20 is provided at the center of the valve chamber 13 so as to be movable in the axial direction (vertical direction). The valve stem 20 has a valve body 21 that performs flow rate measurement in cooperation with the valve port 16 at an intermediate portion, a valve shaft portion 22 and an upper support shaft portion 23 above the valve body 21, and below the valve body 21. Each has a lower support shaft portion 24. The upper support shaft portion 23 is fitted into a bearing hole 18 formed in the valve rod guide member 12, and the lower support shaft portion 24 is inserted into the bearing hole 19 formed in the valve housing 11 through the valve port 16. Match. Thereby, the valve stem 20 is supported by the valve housing 11 and the valve stem guide member 12 so as to be movable in the axial direction (vertical direction).

  The valve body 21 performs flow rate control (flow rate measurement) by changing the opening degree of the valve port 16 by movement in the valve axis direction (vertical direction), and increases the opening degree of the valve port 16 by upward movement. The opening degree of the valve port 16 is decreased by the downward movement. Here, the upward direction of the valve body 21 is defined as the valve opening direction, and the downward direction of the valve body 21 is defined as the valve closing direction.

  An annular pressure receiving plate 26 is attached to the valve shaft portion 22 of the valve stem 20 by a snap ring 25. The pressure receiving plate 26 is in the valve chamber 13 and defines an annular throttle portion 27 between the pressure receiving plate 26 and the inner peripheral wall 13 </ b> A of the valve chamber 13. The pressure receiving plate 26 is subjected to a differential pressure between the pressure on the upstream side of the throttle unit 27 and the pressure on the downstream side caused by the flow rate sensing fluid flowing through the throttle unit 27, and includes the valve body 21 due to a load generated by the differential pressure. The valve stem 20 is driven in the valve opening direction.

  That is, the pressure receiving plate 26 is affected by the pressure difference between the pressure upstream of the flow rate sensing fluid restricting portion 27 flowing in the valve chamber 13 and the pressure of the sensing fluid downstream of the restricting portion 27. A load that correlates with the flow rate of the flow rate sensing fluid flowing through is obtained and displaced upward. Due to the upward displacement of the pressure receiving plate 26, the valve body 21 moves in the valve opening direction.

  Thereby, the opening degree of the valve body 21 (opening degree of the valve port 16) increases in accordance with the increase in the differential pressure acting on the pressure receiving plate 26, that is, the increase in the flow rate of the flow rate sensing fluid flowing through the valve chamber 13. The flow rate of the flow control fluid flowing from the chamber 13 through the valve port 16 to the flow control fluid outlet port 17 increases.

  In this embodiment, the flow sensing fluid and the flow control fluid are the same fluid, and the flow sensing fluid inlet port 14 also serves as the inlet port for the flow control fluid.

  The pressure receiving plate 26 is made of an elastic material such as stainless steel, spring steel, phosphor bronze, elastically deformable plastics, and the like, as shown in FIG. A plurality of slits 26B are formed from the radially outer edge to the middle in the radial direction. In this embodiment, the pressure receiving plate 26 is formed as a leaf spring having four slits 26B formed at equal intervals and having four leaf spring pieces 26C.

  The pressure receiving plate 26 is elastically deformed as shown by the phantom line in FIG. 2 in response to an increase in the differential pressure acting on the pressure receiving plate 26, and the effective effective diameter is reduced by this elastic deformation. Reduce the effective pressure receiving area.

  Further, as shown in FIG. 1, the inner peripheral wall 13A of the valve chamber 13 is a straight cylindrical surface parallel to the valve shaft direction at a portion where the pressure receiving plate 26 is elastically deformed, so that the pressure receiving plate is elastically deformed. As the effective effective diameter of 26 decreases, the passage sectional area of the throttle portion 27 increases.

  In the present embodiment, as shown in FIG. 2, the effective effective diameter of the pressure receiving plate 26 changes between the maximum effective effective diameter Dh and the minimum effective effective diameter Dh ′.

  As shown in FIG. 1, the portion where the pressure receiving plate 26 is fixed to the valve shaft portion 22 by the snap ring 25 (the portion where the slit 26B is not formed around the central hole 26A) is provided with a spring retainer. In addition, a reference spring 30 made of a compression coil spring is attached between this portion of the pressure receiving plate 26 and the valve rod guide member 12 at the upper part of the valve chamber.

  The reference spring 30 presses the pressure receiving plate 26 against the snap ring 25 and urges the valve rod 20 downward in the drawing, that is, in the valve closing direction. The reference spring 30 is a spring means that urges the valve body 21 in a direction opposite to the direction in which the valve body 21 (valve rod 20) is driven by the pressure receiving plate 25.

  The valve housing 11 defines a pressure chamber 32 in cooperation with an adjusting screw plug 31 screwed to the lower portion of the valve housing 11. The lower support shaft portion 24 passes through the bearing hole 19, and the tip thereof is located in the pressure chamber 32. A movable spring receiving member 29 is attached to the tip of the lower support shaft portion 24, and a setting spring 28 by a compression coil spring is attached between the spring receiving member 29 and the adjusting screw plug 31. .

  The setting spring 28 urges the valve stem 20 upward in the drawing, that is, in the valve opening direction, and the effective spring load of the reference spring 30 acting on the valve stem 20 is applied to the valve housing 11 of the adjusting screw plug 31. It is set according to the screwing position for. The effective spring load of the reference spring 30 determines a set flow rate Qs to be described later, and the set value of the set flow rate Qs can be adjusted by the adjustment screw plug 31.

  A communication hole 33 for connecting the valve chamber 13 and the pressure chamber 32 to each other is formed in the valve housing 11. A pressure upstream of the throttle portion 27 of the valve chamber 13 is introduced into the pressure chamber 32 through the communication hole 33.

  As a result, the valve opening load due to the differential pressure generated between the upstream side and the downstream side of the throttle unit 27 when the flow rate sensing fluid flows through the throttle unit 27 is added to the pressure receiving plate 26 and includes the valve shaft unit 22. 20 also works effectively. This increases the pressure receiving area of the differential pressure and contributes to the reduction of the diameter of the valve housing 11.

  FIG. 3 shows an embodiment of a refrigeration cycle apparatus that can be used by incorporating the control valve 10 of Embodiment 1 shown in FIG. 1 as a capacity control valve of a swash plate type variable capacity compressor. ing.

  This refrigeration cycle is used as an in-vehicle air conditioner or the like mounted on a vehicle such as an automobile, and includes a variable capacity compressor 100, a condenser 101, an expansion valve 102, an evaporator 103, and the like. The refrigerant passages 104 to 107 are connected in a loop.

  The variable capacity compressor 100 has a piston 111 whose movement stroke is determined by the inclination angle of the swash plate 110, sucks fluid such as refrigerant from the suction chamber 112 into the compressor chamber 113, and flows into the discharge chamber 114 from the compressor chamber 113. Is discharged. The discharge capacity of the variable capacity compressor 100 increases as the inclination angle of the swash plate 110 increases, and decreases as the inclination angle of the swash plate 110 decreases. The swash plate 110 decreases the inclination angle in accordance with an increase in the pressure in the crank chamber 115, that is, the crank chamber pressure Pc, and increases the inclination angle in accordance with a decrease in the crank chamber pressure Pc.

  The swash plate 110 is in the crank chamber 115 and is connected to the rotating shaft 116. The rotating shaft 116 is drivingly connected to the engine by a pulley 117 and a transmission belt (not shown), and is driven to rotate by the engine.

  The compressor body 130 includes a suction passage 120 that connects the suction chamber 112 and the suction port 121, an upstream discharge passage 122 that communicates with the discharge chamber 114, a downstream discharge passage 124 that communicates with the discharge port 123, a crank A crank chamber passage 125 communicating with the chamber 115, a bleed passage 126 communicating the suction chamber 112 and the crank chamber 115, and a valve mounting bore 127 are formed.

  The control valve 10 is inserted and mounted in the valve mounting bore 127 and is prevented from coming off by a retaining ring 128. The flow sensing fluid inlet port 14 of the control valve 10 mounted on the valve mounting bore 127 is in the upstream discharge passage 122, the flow sensing fluid outlet port 15 is in the downstream discharge passage 124, and the flow control fluid outlet port 17 is in the crank chamber. Each communicates with the passage 125.

  In this case, both the flow rate sensing fluid and the flow rate control fluid are discharge refrigerant discharged from the discharge chamber 114 of the variable displacement compressor 100, and the discharge refrigerant in the discharge chamber 114 flows through the upstream discharge passage 122. It enters the valve chamber 13 from the sensing fluid inlet port 14, flows through the throttle 27, and flows from the flow sensing fluid outlet port 15 through the downstream discharge passage 124 to the discharge port 123.

  Part of the discharged refrigerant that has flowed into the valve chamber 13 has a flow rate determined by the opening of the valve port 16, that is, the vertical position of the valve body 21, and passes through the crank chamber passage 125 from the flow control fluid outlet port 17. It flows into 115. Thereby, the crank chamber pressure Pc is adjusted. In this case, as the opening degree of the valve port 16 is increased, the crank chamber pressure Pc is increased and the inclination angle of the swash plate 110 is decreased, and accordingly, the discharge capacity of the compressor 100 is decreased. The constant flow rate control operation state is entered in a high speed range equal to or higher than the set flow rate Qs at which the control valve 10 opens (see FIG. 6).

  FIG. 1 shows a state in which the control valve 10 is closed. When the control valve 10 is closed, the crank chamber pressure Pc becomes the lowest pressure (equivalent to the intake pressure Ps), the inclination angle of the swash plate 110 becomes maximum, and the variable displacement compressor 100 is in a full load operation state (below the set flow rate). Full stroke operation state).

  When the discharged refrigerant flows through the throttle portion 27 in the valve chamber 13 of the control valve 10, a pressure difference between the upstream side and the downstream side of the throttle portion 27 is generated. Here, the pressure upstream of the throttle 27 is PdH, the pressure downstream of the throttle 27 is PdL, PdH> PdL, and (PdH−PdL) is the differential pressure ΔPd.

  The differential pressure ΔPd acts upward on the pressure receiving plate 26, and the load Wd in the valve opening direction acts on the valve stem 20 by this differential pressure ΔPd. The differential pressure ΔPd increases with an increase in the flow rate of the fluid flowing through the valve chamber 13, that is, the discharge flow rate Qd of the variable displacement compressor 100, so that the valve stem 20 causes the reference spring 30 to increase with an increase in the discharge flow rate Qd. It moves in the valve opening direction against the effective spring load, and the opening degree of the valve port 16 increases.

  The pressure receiving plate 26 is elastically deformed as illustrated in FIG. 2 as the differential pressure ΔPd increases, and the effective effective diameter decreases between the maximum effective effective diameter Dh and the minimum effective effective diameter Dh ′. Accordingly, since the effective pressure receiving area is reduced, the pressure receiving sensitivity of the pressure receiving plate 26 decreases as the discharge flow rate Qd increases. In addition, the passage cross-sectional area of the throttle portion 27 increases as the pressure receiving plate 26 is elastically deformed. Therefore, as the discharge flow rate Qd increases, the degree of occurrence of the differential pressure ΔPd decreases.

  As a result, the rate of change of the generated load Wd with respect to the discharge flow rate Qd in the large flow rate region is reduced compared to that in the small flow rate region, and the change rate of the generated load Wd with respect to the discharge flow rate Qd is changed. Thus, the Qd-Wd characteristic becomes closer to a straight line than the quadratic curve (conventional product Qd-Wd characteristic D) as indicated by C in FIGS. 4 shows the Qd-Wd characteristic when the pressure receiving plate 26 having a relatively small pressure receiving area is used, and FIG. 5 shows the Qd-Wd characteristic when the pressure receiving plate 26 having a relatively large pressure receiving area is used. ing.

  As a result, as shown in FIGS. 4 and 5, in the control valve 10 according to the present invention, a control allowable range (φDh to φDh ′ control allowable range) E indicating approximate linearity with respect to the Qd-Wd characteristic is obtained. It can be set larger than the control allowable range (φDh constant control allowable range) F of the conventional product so that the change width of the generated load Wd can be reduced or the change width of the discharge flow rate Qd with respect to the generated load change width can be increased. Become.

  According to the control valve 10 of the present embodiment, as shown in FIG. 6, in the high speed range where the compressor rotational speed is equal to or higher than the set flow point, the control valve 10 is in the control range where the valve is opened. 100 becomes a stable constant flow rate control operation state with the set flow rate Qs. The discharge flow rate characteristic with respect to the compressor rotational speed in this case is indicated by a symbol G in FIG.

  In contrast, in the conventional product (φDh constant), the discharge valve Qd tends to decrease as indicated by the symbol H in FIG. Is seen, resulting in a lack of ability.

  The elastic deformation characteristics of the pressure receiving plate 26 with respect to the discharge flow rate Qd can be arbitrarily set according to the spring constant of the pressure receiving plate 26 itself, the plate thickness, the length and width of the slits 26B, the number, and the like. By optimally setting the deformation characteristics, the Qd-Wd characteristics can be set to ones that are more excellent in linearity or matched to the compressor characteristics.

  In addition, a difference in plate thickness is provided between the outer peripheral edge side of the pressure receiving plate 26 and the center hole 26A side, or a plurality of plates having different outer diameter dimensions are laminated to form the pressure receiving plate 26. The elastic deformation characteristic can be optimally set, and the Qd-Wd characteristic can be set to a more excellent linearity.

  A control valve according to a second embodiment of the present invention will be described with reference to FIG. 7, parts corresponding to those in FIG. 1 are denoted by the same reference numerals as those in FIG. 1, and description thereof is omitted.

  In this embodiment, the valve rod 20 is constituted by a hollow shaft, and the pressure (PdL) downstream from the throttle portion 27 of the valve chamber 13 is introduced into the pressure chamber 32 by the hollow hole 34 of the valve rod 20. In this embodiment, the communication hole 33 that connects the valve chamber 13 and the pressure chamber 32 to each other is omitted.

  Also in this embodiment, the pressure receiving plate 26 is made of an elastic material as in the first embodiment, and in accordance with an increase in the differential pressure acting on the pressure receiving plate 26, as shown by a virtual line in FIG. The effective effective diameter is reduced by this elastic deformation, and the effective pressure receiving area is reduced accordingly. Therefore, this embodiment can provide the same effects as those of the first embodiment.

  FIG. 8 shows an embodiment of a refrigeration cycle apparatus that can be used by incorporating the control valve 10 of Embodiment 2 shown in FIG. 7 as a capacity control valve of a swash plate type variable capacity compressor. ing. 8, parts corresponding to those in FIG. 3 are denoted by the same reference numerals as those in FIG. 3, and description thereof is omitted.

  Also in this case, the same operation and effect as the variable displacement compressor 100 shown in FIG. 3 can be obtained.

  Embodiment 3 of the control valve according to the present invention will be described with reference to FIG.

  The control valve of this embodiment is indicated by the reference numeral 50 as a whole. The control valve 50 has a valve housing 51. The valve housing 51 has a cup shape and is fastened to an upper opening by caulking, for example, an attractor 81 of an electromagnetic coil device 80 described later, and cooperates with the attractor 81 to define a cylindrical chamber-like valve chamber 52. Yes.

  The valve housing 51 is formed with a sensing fluid inlet port 53 that opens to the lower region of the valve chamber 52 and a sensing fluid outlet port 54 that opens to the upper region of the valve chamber 52. The sensing fluid flows into the valve chamber 52 from the sensing fluid inlet port 53. The sensing fluid flows from the lower side to the upper side in the valve chamber 52, and flows out of the valve chamber 52 from the sensing fluid outlet port 54.

  The valve housing 51 is formed with a valve port 56 that opens to the bottom bottom of the valve chamber 52 and a controlled fluid outlet port 55 that communicates with the valve port 56 on the opposite side of the valve chamber 52.

  A valve rod 60 is provided at the center of the valve chamber 52 so as to be movable in the axial direction (vertical direction). The valve rod 60 is integrally formed with a valve body 61 that cooperates with the valve port 56 to measure the flow rate at an intermediate portion. The valve body 61 is located in the valve chamber 52 and performs flow rate control (flow rate measurement) by changing the opening degree of the valve port 56 by movement in the valve lift direction (vertical direction). The opening degree of 56 is increased, and the opening degree of the valve port 56 is decreased by the downward movement. Also in this embodiment, the upward direction of the valve body 61 is defined as the valve opening direction, and the downward direction of the valve body 61 is defined as the valve closing direction.

  An annular pressure receiving plate 64 is attached to the valve shaft 62 of the valve stem 60 by a snap ring 63. The pressure receiving plate 64 is in the valve chamber 52 and defines an annular throttle portion 65 between the pressure receiving plate 64 and the inner peripheral wall 52 </ b> A of the valve chamber 52. The pressure receiving plate 64 is subjected to a differential pressure between the pressure on the upstream side and the pressure on the downstream side of the throttle unit 65 generated by the flow rate sensing fluid flowing through the throttle unit 65, and includes the valve body 61 due to a load generated by the differential pressure. The valve stem 60 is driven in the valve opening direction.

  In other words, the pressure receiving plate 64 is affected by the pressure difference between the pressure upstream of the flow sensing fluid restricting portion 65 flowing in the valve chamber 52 and the pressure of the sensing fluid downstream of the restricting portion 65. A load that correlates with the flow rate of the flow rate sensing fluid flowing through is obtained and displaced upward. Due to the upward displacement of the pressure receiving plate 64, the valve body 61 moves in the valve opening direction.

  As a result, the opening of the valve body 61 (opening of the valve port 56) increases in accordance with an increase in the differential pressure acting on the pressure receiving plate 64, that is, an increase in the flow rate of the flow rate sensing fluid flowing through the valve chamber 52. The flow rate of the flow control fluid flowing from the chamber 52 through the valve port 56 to the flow control fluid outlet port 55 increases.

  In this embodiment as well, the flow sensing fluid and the flow control fluid are the same fluid, and the flow sensing fluid inlet port 53 also serves as the inlet port for the flow control fluid.

  The pressure receiving plate 64 is made of an elastic material such as stainless steel, spring steel, phosphor bronze, elastically deformable plastics, etc., as in the above-described embodiment, and has a central hole through which the valve shaft portion 22 passes. A plurality of slits are formed in the radial direction from the radial outer edge.

  The pressure receiving plate 64 is elastically deformed as the differential pressure acting on the pressure receiving plate 64 increases, and the effective effective diameter is reduced by the elastic deformation, and the effective pressure receiving area is reduced accordingly.

  Also in this embodiment, since the inner peripheral wall 52A of the valve chamber 52 is a straight cylindrical surface parallel to the valve axis direction at the portion where the pressure receiving plate 64 is elastically deformed, the effective effective diameter of the pressure receiving plate 64 is reduced by elastic deformation. As a result, the passage sectional area of the throttle 65 increases.

  A portion where the pressure receiving plate 64 is fixed to the valve shaft portion 62 by the snap ring 63 (portion around the center hole) also serves as a spring retainer, and this portion of the pressure receiving plate 64 and the lower bottom surface portion of the valve chamber 52 An auxiliary spring (spring means) 66 by a compression coil spring is attached between them.

  The auxiliary spring 66 presses the pressure receiving plate 64 against the snap ring 63 and biases the valve rod 60 upward in the drawing, that is, in the valve opening direction.

  The valve housing 51 cooperates with a spring retainer member 67 fixedly attached to the lower end portion of the valve housing 51 to define a pressure equalizing chamber 68. An external pressure equalization introduction port 69 is formed through the spring retainer member 67.

  The lower portion of the valve stem 60 penetrates the valve port 56 in a loosely fitted state, extends across the controlled fluid outlet port 55, and extends axially into the valve stem support hole 70 formed in the valve housing 51. It is slidably fitted. Further, the lower end of the valve stem 60 passes through the valve stem support hole 70 and is located in the pressure equalizing chamber 68.

  A spring receiving member 71 is attached to the lower end of the valve stem 60 located in the pressure equalizing chamber 68, and a setting spring (spring) is formed between the spring receiving member 71 and the spring retainer member 67 by a compression coil spring. Means) 72 is attached. The setting spring 72 biases the valve rod 60 (valve element 61) in the valve opening direction.

  An electromagnetic coil device 80 as electromagnetic means is attached to the upper end of the plunger tube 82, the suction element 81 coupled to the upper end of the valve housing 51 by caulking or the like, the plunger tube 82 fixed to the upper part of the suction element 81. A coil guide plug member 83, a plunger 85 provided to be movable in the axial direction in a plunger chamber 84 defined inside the plunger tube 82, a bobbin 86 and a winding portion 87 attached to the outside of the plunger tube 82 And an outer casing 89 attached to the outside of the suction element 81 by the lower lid member 88.

  The suction element 81 is fixedly arranged closer to the valve chamber 52 than the plunger chamber 84. The suction element 81 opens to the valve chamber 52 at one end (lower end) and to the plunger chamber 84 at the other end (upper end). An open center hole 90 is formed through.

  The inner diameter of the center hole 90 is sufficiently larger than the outer diameter of the valve stem 60, and the valve shaft portion 62 of the valve stem 60 is inserted into the center hole 90 in a non-contact state. The upper end side of the valve shaft portion 62 enters the plunger chamber 84 penetrating the center hole 90 and is fixedly connected to the plunger 85. The valve stem 60 is made of a non-magnetic material and also serves as a plunger rod.

  Since the plunger chamber 84 communicates with the valve chamber 52 through the central hole 90, the internal pressure of the plunger chamber 84 is the internal pressure of the valve chamber 52, specifically, the pressure of the sensing fluid downstream from the pressure receiving plate 64 (sensing fluid). Approximately equal to the pressure at the outlet port 54).

  A pressure equalizing hole 91 is formed in the plunger 85 so as to penetrate the entire area of the plunger chamber 84 at a uniform pressure.

  The electromagnetic coil device 80 energizes the winding portion 87 to generate an electromagnetic force corresponding to the coil current, and the conical convex shape of the plunger 85 is formed on the conical concave magnetic adsorption surface (upper surface) of the attractor 81. The lower surface is magnetically attracted, and the valve rod 60 (valve element 61) is urged in the valve closing direction (downward).

  As a result, the set flow rate of the variable displacement compressor controlled by the control valve 50 includes the magnetic attractive force in the valve closing direction by the electromagnetic coil device 80 and the spring force in the valve opening direction of the auxiliary spring 66 and the setting spring 72. Determined by the equilibrium relationship. Thereby, the set flow rate of the variable capacity compressor is variably set by the current control of the electromagnetic coil device 80. The auxiliary spring 66 is a spring for fully opening the control valve 50 when the power is off.

  Also in this embodiment, the pressure receiving plate 64 is made of an elastic material as in the first embodiment, and the pressure receiving plate 64 is elastically deformed according to an increase in the differential pressure acting on the pressure receiving plate 64, and the effective effective diameter is caused by this elastic deformation. Since the effective pressure receiving area is reduced accordingly, the same effect as in the first embodiment can be obtained. It is also possible to change to an elastic deformation characteristic correlated with the attractive force characteristic of the electromagnetic coil device.

  FIG. 10 shows an embodiment of a refrigeration cycle apparatus that can be used by incorporating the control valve 50 of Embodiment 3 shown in FIG. 9 as a capacity control valve of a swash plate type variable capacity compressor. ing. In FIG. 10 as well, portions corresponding to those in FIG. 3 are denoted by the same reference numerals as those in FIG. 3, and description thereof is omitted.

  In this embodiment, the set flow rate can be variably set by the current control of the electromagnetic coil device 80, and the same operation and effect as the variable displacement compressor 100 shown in FIG. 3 can be obtained.

  As with the control valve 10 of the first embodiment, the control valve 50 has a control allowable range showing approximate linearity with respect to the Qd-Wd characteristic that is larger than the control allowable range of the conventional product. As shown in FIG. 11, the discharge flow rate Qd can be arbitrarily controlled and set within the range of the full load operation capacity in a range from a small flow rate to a large flow rate regardless of the compressor rotational speed.

It is a longitudinal cross-sectional view which shows Embodiment 1 of the control valve by this invention. It is a perspective view which shows one Embodiment of the pressure receiving plate used for the control valve by this invention. It is explanatory drawing which shows one Embodiment of the refrigerating-cycle apparatus which can incorporate and use the control valve of Embodiment 1 as a capacity | capacitance control valve of a swash plate type variable capacity compressor. It is a graph which shows the relationship between the flow volume and differential pressure (generated load) in the control valve by this invention. It is a graph which shows the relationship between the flow volume and differential pressure (generated load) in the control valve by this invention. It is a graph which shows the control characteristic of the compressor rotation speed-discharge flow rate of the capacity | capacitance variable type compressor by the control valve of Embodiment 1. FIG. It is a longitudinal cross-sectional view which shows Embodiment 2 of the control valve by this invention. It is explanatory drawing which shows one Embodiment of the refrigerating-cycle apparatus which can incorporate and use the control valve of Embodiment 2 as a capacity | capacitance control valve of a swash plate type variable capacity compressor. It is a longitudinal cross-sectional view which shows Embodiment 3 of the control valve by this invention. It is explanatory drawing which shows one Embodiment of the refrigerating-cycle apparatus which can incorporate and use the control valve of Embodiment 3 as a capacity | capacitance control valve of a swash plate type variable capacity compressor. 7 is a graph showing control characteristics of compressor rotation speed-discharge flow rate of a variable displacement compressor by a control valve according to a third embodiment. It is a graph which shows the relationship between the flow volume and generated load in a control valve.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Control valve 11 Valve housing 12 Valve rod guide member 13 Valve chamber 13A Inner peripheral wall 14 Flow rate sensing fluid inlet port 15 Flow rate sensing fluid outlet port 16 Valve port 17 Flow rate control fluid outlet port 18, 19 Bearing hole 20 Valve rod 21 Valve body 22 Valve shaft portion 23 Upper support shaft portion 24 Lower support shaft portion 25 Snap ring 26 Pressure receiving plate 26A Center hole 26B Slit 26C Leaf spring piece 27 Restriction portion 28 Setting spring 29 Spring receiving member 30 Reference spring 31 Adjustment screw plug 32 Pressure chamber 33 Communication hole 34 Hollow hole 50 Control valve 51 Valve housing 52 Valve chamber 52A Inner peripheral wall 53 Sensing fluid inlet port 54 Sensing fluid outlet port 55 Controlled fluid outlet port 56 Valve port 60 Valve rod 61 Valve body 62 Valve shaft portion 63 Snap ring 64 Pressure receiving plate 65 Restriction part 66 Auxiliary spring 67 Spring retainer Member 68 Pressure equalizing chamber 69 External pressure equalizing introduction port 70 Valve rod support hole 71 Spring receiving member 72 Setting spring 80 Electromagnetic coil device 81 Suction element 82 Plunger tube 83 Coil guide plug member 84 Plunger chamber 85 Plunger 86 Bobbin 87 Winding portion 88 Lower cover member 89 Outer casing 90 Center hole 91 Pressure equalizing hole 100 Variable displacement compressor 101 Condenser 102 Expansion valve 103 Evaporator 104-107 Refrigerant passage 110 Swash plate 111 Piston 112 Suction chamber 113 Compressor chamber 114 Discharge chamber 120 Suction passage 121 Suction port 122 Upstream discharge passage 123 Discharge port 124 Downstream discharge passage 125 Crank chamber passage 126 Extraction passage 127 Valve mounting bore 128 Retaining ring 130 Compressor body

Claims (9)

In the valve chamber formed in the valve housing, a valve body that performs flow rate control by changing the opening of the valve port by movement in the valve shaft direction, and a pressure receiving plate attached to the valve shaft portion of the valve body are provided. The pressure receiving plate defines a throttle portion between the pressure chamber and the valve chamber wall, and exerts a differential pressure between a pressure on the upstream side of the throttle portion and a pressure on the downstream side caused by fluid flowing through the throttle portion. In the control valve for driving the valve body in the valve shaft direction by the generated load due to the differential pressure,
The control valve, wherein the pressure receiving plate is made of an elastic material, and the pressure receiving plate is elastically deformed according to an increase in the differential pressure to reduce an effective pressure receiving area.   2. The control valve according to claim 1, wherein the pressure receiving plate decreases an effective pressure receiving area by elastic deformation according to an increase in the differential pressure and increases a passage cross-sectional area of the throttle portion.   3. The control valve according to claim 1, wherein the pressure receiving plate is configured by a leaf spring in which a slit is formed from a radially outer edge to a middle portion in the radial direction.   The control valve according to claim 1, wherein the differential pressure is configured to act on the valve shaft portion itself.   The control valve according to any one of claims 1 to 4, further comprising spring means for urging the valve body in a direction opposite to a direction in which the valve body is driven by the pressure receiving plate.   Electromagnetic means for urging the valve body by an electromagnetic force in a direction opposite to the driving direction by the pressure receiving plate; and spring means for urging the valve body in the same direction as the driving direction of the valve body by the pressure receiving plate; The control valve according to claim 1, comprising: Used as a capacity control valve for variable displacement compressors that quantitatively change the discharge capacity according to the crank chamber pressure,
The fluid flowing through the discharge flow path of the variable capacity compressor is introduced into the valve chamber, and the pressure receiving plate is moved by the differential pressure generated between the upstream side and the downstream side of the throttle passage according to the flow rate of the fluid. The control valve according to any one of claims 1 to 6, wherein the valve body is driven in a valve opening direction, and the valve body controls a flow rate of a fluid flowing from the discharge passage to the crank chamber. A variable displacement compressor that quantitatively changes the discharge capacity according to the crank chamber pressure,
A variable displacement compressor in which the control valve according to claim 7 is inserted and mounted in a valve mounting bore formed in the compressor body.   8. A refrigeration cycle apparatus having a variable capacity compressor, a condenser, an expansion means, an evaporator, and a refrigerant passage connecting these in a loop, and including the control valve according to claim 7.

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