JP2015010694A - Fluid proportional valve - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fluid proportional valve capable of stabilizing a flow rate of fluid at the time of low flow rate by restricting a swing of a valve shaft of a valving element.SOLUTION: An elastic body 30 for biasing a valving element 50 is installed at the side opposite to a diaphragm 40 in respect to the valving element 50 in order to push the valving element 50 supported at the diaphragm 40 through a valve shaft 52 against a valve seat 38. An elastic body 60 having a part far from the valving element 50 rather than a part near the valving element 50 exhibits a low rigidity toward a direction orthogonal to the valve shaft 52. As one end side of the elastic body 60 near the valving element 50 is displaced along with a swinging of the valve shaft 52, the one end side is not deformed, but the another end is easily deformed. A slight displacement at the one end side of the elastic body 60 is transmitted to the another end side spaced apart from the one end side in respect to a fulcrum point of swing of the valve shaft 52, thereby the another end side is widely deformed and a motion of the another end side returned by its resilience is transmitted to enable the one end side to be precisely returned to a position before its displacement and a slight swing of the valve shaft 52 can be restricted with a high precision.

Description

  The present invention relates to a fluid proportional valve that controls the flow rate of a fluid.

  In gas equipment such as a water heater, a gas proportional valve is used to control the flow rate of gas supplied to the burner. The gas proportional valve includes a valve seat provided with a valve hole communicating with the gas inlet chamber and the gas outlet chamber, and a valve body that closes the valve hole by contacting the valve seat from the gas outlet chamber side, A structure is known in which a valve element is supported via a valve shaft on a diaphragm provided on the gas inlet chamber side so as to face the valve hole (for example, Patent Document 1). In this gas proportional valve, when the electromagnetic coil is energized, the movable iron core that is drawn into the electromagnetic coil according to the current value presses the end of the valve shaft from the diaphragm side, so that the valve element is opened away from the valve seat. On the other hand, when the energization to the electromagnetic coil is stopped, the movable iron core is not drawn into the electromagnetic coil, and the valve body is pressed against the valve seat by the biasing force of the coil spring installed in the gas outlet chamber to close the valve.

Japanese Utility Model Publication No. 57-35572

  However, the gas proportional valve disclosed in Patent Document 1 has a problem that the gas flow rate at a small gas flow rate is not stable. This is because, when the gas flow rate is small, the gap between the valve seat and the valve body (opening area of the valve hole) varies greatly due to slight fluctuation of the valve shaft when the valve is opened.

  The present invention has been made in response to the above-described problems in the prior art, and is a fluid proportional valve capable of stabilizing the flow rate of a fluid at a small flow rate by suppressing the shake of the valve shaft of the valve body. For the purpose of provision.

In order to solve the above-described problems, the fluid proportional valve of the present invention employs the following configuration. That is,
A valve seat provided with a valve hole through which a fluid passes, and the valve seat is closed by being urged by an elastic body to the valve seat, and the valve shaft is opposite to the side urged by the elastic body Projecting valve body, a diaphragm supporting the valve body at an end of the valve shaft opposite to the valve body, and an end of the valve shaft on the diaphragm side biasing force of the elastic body A drive unit that moves the valve body pressed against the valve seat in the axial direction of the valve shaft by driving against the valve seat, and passes through the valve hole according to the amount of movement of the valve body In a fluid proportional valve for controlling the flow rate of the fluid,
The elastic body is characterized in that the rigidity in the direction orthogonal to the valve shaft is lower on the side farther from the valve body than on the side closer to the valve body.

  In such a fluid proportional valve, the valve stem of the valve body shakes when the valve body is away from the valve seat (opened state), and the valve shaft is in the radial direction (perpendicular to the axial direction) with the end supported by the diaphragm as a fulcrum. Caused by swaying in the direction of movement). In the fluid proportional valve of the present invention, when the one end side of the elastic body close to the valve body is displaced according to the shake of the valve shaft, the other end side having a lower radial rigidity than the one end side is easily deformed. Since the other end side of the elastic body is further away from the one end side than the fulcrum of the valve shaft shake, the displacement amount (blur width) transmitted to the other end side is larger than the displacement amount on the one end side. . For this reason, in the elastic body of the present invention, even if the displacement amount on one end side is small, the other end side is greatly deformed, and the movement of the other end side returning to the original state by the restoring force is transmitted to the one end side. It is possible to accurately return to the position before the displacement. Thereby, compared with the case where the whole is deformed little by little with the elastic body having uniform rigidity, slight fluctuation of the valve shaft at the position of the valve body (one end side of the elastic body) can be suppressed with high accuracy. As a result, the flow rate of the fluid can be stabilized while maintaining the distance between the valve body and the valve seat (opening area of the valve hole).

  In the fluid proportional valve of the present invention described above, a coil spring having a larger coil diameter on the side farther from the valve body than on the side closer to the valve body may be used as the elastic body.

  Since such a coil spring has a lower radial rigidity on the large diameter side where the coil diameter is larger than that on the small diameter side where the coil diameter is small, when one end side close to the valve body is displaced according to the fluctuation of the valve shaft, The other end side (large diameter side) is easily deformed without deformation on the small diameter side. Then, a slight displacement on one end side of the coil spring is transmitted to the other end side that is farther from the one end side with respect to the fulcrum of the valve shaft, so that the other end side is greatly deformed and the other end side is a restoring force. Since the movement of returning to the one end side is transmitted to the one end side, the one end side can be accurately returned to the position before the displacement. Therefore, slight blurring of the valve shaft at the position of the valve body (one end side of the coil spring) can be suppressed with high accuracy.

  Further, in the coil spring, when a radial force is applied to one end side in a state where the coil spring is compressed in the axial direction, the winding is displaced in the radial direction, so-called bending occurs. In a state where the body is bent, a part of the compressive force is applied in the direction in which the winding is displaced, so that it is difficult to generate a restoring force in the radial direction. In terms of such torsion, a conical coil spring having a coil diameter on the other end side larger than that on one end side is smaller in diameter than the cylindrical coil spring wound around the same coil diameter as the coil diameter on the smaller diameter side. The width of the winding deviation until the torsion occurs due to the force of the direction is large, and the torsion hardly occurs. Further, the conical coil spring which does not cause the bending of the body generates a restoring force against the shake of the valve shaft in the radial direction, so that the shake of the valve shaft can be suppressed.

  In such a fluid proportional valve of the present invention, a coil spring in which the cross-sectional area of the winding on the side farther from the valve body is smaller than the side closer to the valve body may be used as the elastic body.

  In such a coil spring, since the rigidity in the radial direction is lower on the thin wire side where the cross-sectional area is smaller than the thick wire side where the cross-sectional area of the winding is large, if one end side close to the valve body is displaced according to the shake of the valve shaft, The other side (thin line side) is easily deformed without deforming the side (thick line side). Then, a slight displacement on one end side of the coil spring is transmitted to the other end side that is farther from the one end side with respect to the fulcrum of the valve shaft, so that the other end side is greatly deformed and the other end side is a restoring force. Since the movement of returning to the one end side is transmitted to the one end side, the one end side can be accurately returned to the position before the displacement. Therefore, slight blurring of the valve shaft at the position of the valve body (one end side of the coil spring) can be suppressed with high accuracy.

  In such a fluid proportional valve of the present invention, a coil spring having a larger number of turns per unit length on the side farther from the valve body than on the side closer to the valve body may be used as the elastic body.

  In such a coil spring, since the rigidity in the radial direction is lower on the densely wound side having a larger number of turns than the lessly wound side having a smaller number of turns, when one end side close to the valve body is displaced according to the shake of the valve shaft, The (sparsely wound side) is not deformed, and the other end side (closely wound side) is easily deformed. Then, a slight displacement on one end side of the coil spring is transmitted to the other end side that is farther from the one end side with respect to the fulcrum of the valve shaft, so that the other end side is greatly deformed and the other end side is a restoring force. Since the movement of returning to the one end side is transmitted to the one end side, the one end side can be accurately returned to the position before the displacement. Therefore, slight blurring of the valve shaft at the position of the valve body (one end side of the coil spring) can be suppressed with high accuracy.

It is sectional drawing which showed the internal structure of the gas proportional valve 10 of a present Example. It is explanatory drawing which compared the conical coil spring 60 of the present Example with the general cylindrical coil spring 90. FIG. It is explanatory drawing which showed a mode that the conical coil spring 60 of a present Example deform | transforms by the shaking of the valve shaft 52 compared with the general cylindrical coil spring 90. FIG. It is sectional drawing which showed the structure of the urging | biasing spring 100 installed in the gas outlet chamber 34 of a 1st modification. It is sectional drawing which showed the shape of the urging | biasing spring 110 installed in the gas outlet chamber 34 of a 2nd modification. It is sectional drawing which showed the shape of the urging | biasing spring 120 installed in the gas outlet chamber 34 of a 3rd modification.

  FIG. 1 is a cross-sectional view showing the internal structure of the gas proportional valve 10 of this embodiment. The gas proportional valve 10 is used to control the flow rate of gas supplied to a burner (not shown) of a gas device such as a water heater. As shown in the figure, the gas proportional valve 10 has a main body case 20 formed by superposing an upper case 22 and a lower case 24 formed in a cylindrical shape. A gas inlet 28 through which gas flows is provided on the peripheral surface of the upper case 22, and a gas outlet 32 through which gas flows out is provided at the peripheral surface of the lower case 24. The gas proportional valve 10 of this embodiment corresponds to the “fluid proportional valve” of the present invention.

  A gas inlet chamber 30 connected to the gas inlet 28, a gas outlet chamber 34 connected to the gas outlet 32, and a circular valve hole 36 communicating the gas inlet chamber 30 and the gas outlet chamber 34 are formed in the main body case 20. A valve seat 38 is provided. The gas inlet chamber 30 is covered with a circular diaphragm 40 on the side opposite to the side where the valve hole 36 opens (upper part in the drawing). The outer edge of the diaphragm 40 is fitted into a shallow recess formed in the inner periphery of the upper end of the upper case 22 and is sandwiched between the cover plate 26 having an opening at the center and the upper case 22.

  In addition, a valve body 50 that closes the valve hole 36 by contacting the valve seat 38 from the gas outlet chamber 34 side is accommodated in the main body case 20. The valve body 50 is formed in a tapered shape in which the cross-sectional area on the gas outlet chamber 34 side is wider than the gas inlet chamber 30 side, and is supported by the diaphragm 40 via a cylindrical valve shaft 52. A small-diameter portion 54 protrudes from the upper end surface of the valve shaft 52 in contact with the diaphragm 40, and an annular fastener 56 has a small diameter in a state where the small-diameter portion 54 is inserted into a hole penetrating through the center of the diaphragm 40. The diaphragm 40 is sandwiched by being fitted into the portion 54. Further, the upper end side of the small diameter portion 54 is pierced through the opening of the lid plate 26.

  In the gas outlet chamber 34, an urging spring 60 that urges the valve body 50 in a direction (upward in the figure) to press the valve body 50 against the valve seat 38 is installed. The biasing spring 60 of this embodiment uses a conical coil spring, and the coil diameter on the other end side fixed to the bottom surface of the gas outlet chamber 34 is larger than the one end side fixed to the valve body 50. It has become.

  Above the gas inlet chamber 30, an actuator 70 for driving the valve body 50 is installed on the upper surface of the lid plate 26. The actuator 70 includes an electromagnetic coil 72 formed in a cylindrical shape by winding an electric wire, and a movable iron core 74 that is slidably inserted into the central axis of the electromagnetic coil 72. The lower end is in contact with the upper end of the small diameter portion 54. A pressing spring 76 is provided between the upper surface plate 78 covering the upper portion of the actuator 70 and the movable iron core 74, and urges the movable iron core 74 toward the small diameter portion 54. The pressing spring 76 is a cylindrical coil spring. Further, the actuator 70 of the present embodiment corresponds to a “drive unit” of the present invention.

  The gas proportional valve 10 having such a structure operates as follows. First, as shown in FIG. 1, when the electromagnetic coil 72 is not energized, the valve body 50 is pressed against the valve seat 38 by the biasing force of the biasing spring 60, and the valve body 50 blocks the valve hole 36. The gas proportional valve 10 is closed. The urging force of the urging spring 60 is set so as to push up the movable iron core 74, the valve shaft 52, and the valve body 50 against the urging force of the pressing spring 76. The urging spring 60 of this embodiment corresponds to the “elastic body” of the present invention.

  When the electromagnetic coil 72 of the gas proportional valve 10 in the closed state is energized, the movable iron core 74 is drawn into the electromagnetic coil 72 by the magnetic force generated according to the current value, and the valve shaft 52 is pushed down through the small diameter portion 54. . As a result, the valve body 50 is separated from the valve seat 38 and the gas proportional valve 10 is opened. When the valve body 50 formed in a tapered shape moves downward according to the current value, the gap between the valve body 50 and the valve seat 38 (opening area of the valve hole 36) increases accordingly, and the gas flow rate increases. .

  Further, the valve body 50 supported by the diaphragm 40 via the valve shaft 52 is displaced according to the change in the gas pressure in the gas inlet chamber 30, thereby suppressing the change in the gas pressure in the gas outlet chamber 34. it can. For example, when the gas pressure in the gas inlet chamber 30 rises, the diaphragm 40 swells upward, and accordingly, the valve body 50 is pulled up to reduce the opening area of the valve hole 36. As a result, the gas flow rate is suppressed, and the gas pressure in the gas outlet chamber 34 is maintained at a predetermined pressure corresponding to the current value supplied to the electromagnetic coil 72. On the contrary, when the gas pressure in the gas inlet chamber 30 is lowered, the valve body 50 is pushed down as the diaphragm 40 is lowered, so that the gas flow rate is increased and the gas pressure in the gas outlet chamber 34 is maintained. .

  On the other hand, when the energization to the electromagnetic coil 72 is stopped and the magnetic force that pulls the movable iron core 74 into the electromagnetic coil 72 disappears, the valve body 50 is pushed up by the urging force of the urging spring 60 to close the valve hole 36, and the gas proportional The valve 10 returns to the closed state.

  In the gas proportional valve 10 operating as described above, when the valve shaft 52 is shaken (swaying in the radial direction) in response to an impact or vibration from the outside in the opened state, the gap between the valve body 50 and the valve seat 38 ( The opening area of the valve hole 36 varies. In particular, when the gas flow rate is set to be small (the opening area of the valve hole 36 is set small), the rate of change of the opening area due to slight shaking of the valve shaft 52 is large, so that the gas flow rate is not stable. Further, noise is generated when the valve body 50 collides with the valve seat 38. Therefore, in the gas proportional valve 10 of the present embodiment, a conical coil spring is adopted as the biasing spring 60 in order to suppress the shake of the valve shaft 52.

  FIG. 2 is an explanatory diagram comparing the conical coil spring 60 of the present embodiment with a general cylindrical coil spring 90. In addition, the white arrow in a figure represents the direction of the force added to a coil spring (60,90). First, in the cylindrical uniform coil spring 90 shown in FIG. 2A, when a force in the radial direction (right direction in the illustrated example) is applied to the upper end side in a state compressed in the axial direction, As shown by the broken line, the winding is displaced in the radial direction, so-called bending occurs. In a state where the body is bent, a part of the compressive force is applied in a direction in which the winding is displaced (right direction in the drawing), and thus it is difficult to generate a restoring force against the radial shake of the valve shaft 52.

  On the other hand, in the conical coil spring 60 shown in FIG. 2B, assuming that the coil diameter on the small diameter side (upper end side) is the same as the coil diameter of the cylindrical coil spring 90 in FIG. The winding displacement in the radial direction until the torsion as shown by the broken line in FIG. 3 is larger than that of the cylindrical coil spring 90, and the torsion hardly occurs. Further, the conical coil spring 60 which does not cause the bending of the body generates a restoring force against the shake of the valve shaft 52 in the radial direction, so that the shake of the valve shaft 52 can be suppressed.

  FIG. 3 is an explanatory view showing a state in which the conical coil spring 60 of the present embodiment is deformed by the shake of the valve shaft 52 in comparison with a general cylindrical coil spring 90. FIG. 3 shows a cross-sectional view of the valve shaft 52 and the coil springs (60, 90) cut along a plane including the center line of the valve shaft 52. The shake of the valve shaft 52 is caused by the valve shaft 52 swaying in the radial direction (direction orthogonal to the axial direction) with the small diameter portion 54 supported by the diaphragm 40 as a fulcrum. In the cylindrical uniform coil spring 90 shown in FIG. 3A, when the upper end fixed to the valve body 50 is displaced in accordance with the shake of the valve shaft 52, the entire coil spring 90 is uniformly deformed. In such a coil spring 90, if the amount of displacement on the upper end side is small, the amount of deformation of each part of the coil spring 90 is also small, so it is difficult to obtain accuracy in the operation of returning the slight displacement on the upper end side by the restoring force. . Therefore, it is difficult to suppress slight shaking of the valve shaft 52 with the cylindrical coil spring 90 having a uniform shape.

  On the other hand, in the conical coil spring 60 shown in FIG. 3B, the coil diameter is larger than that of the small coil diameter when the winding for one round is received by receiving the radial force. Since the winding may be smaller in bending, the radial rigidity is lower on the large diameter side than on the small diameter side. For this reason, when the upper end of the coil spring 60 fixed to the valve body 50 is displaced according to the movement of the valve shaft 52, the lower end side (large diameter side) is easily deformed rather than the upper end side (small diameter side). Further, since the lower end side of the coil spring 60 is farther from the upper end side than the upper end side with respect to the fulcrum of movement of the valve shaft 52, the displacement amount (blur width) transmitted to the lower end side is the displacement amount on the upper end side. Bigger than. In such a conical coil spring 60, even if the amount of displacement on the upper end side is slight, the lower end side is greatly deformed, and the movement of the lower end side returning to the original state by the restoring force is transmitted to the upper end side, thereby displacing the upper end side. It is possible to return to the previous position with high accuracy. Thereby, compared with the cylindrical coil spring 90 of FIG. 3A, slight blurring of the valve shaft 52 at the position of the valve body 50 (the upper end of the coil spring 60) can be suppressed with high accuracy. As a result, even when the small gas flow rate is set, the gas flow rate can be stabilized and the generation of noise due to the collision of the valve body 50 with the valve seat 38 can be suppressed.

  The following modification is also present in the gas proportional valve 10 of the present embodiment described above. In the following, a modified example will be described focusing on parts different from the above-described embodiment.

  FIG. 4 is a cross-sectional view showing the structure of the biasing spring 100 installed in the gas outlet chamber 34 of the first modification. As shown in the figure, the urging spring 100 of the first modification includes two cylindrical coil springs 102 and 104 having different coil diameters and an annular washer 106, and a small coil spring 102 having a small coil diameter. Is attached to the upper surface of the washer 106, and a large coil spring 104 having a large coil diameter is attached to the lower surface of the washer 106. The biasing spring 100 has a small coil spring 102 side fixed to the valve body 50 and a large coil spring 104 side fixed to the bottom surface of the gas outlet chamber 34. The biasing spring 100 of the first modification corresponds to the “elastic body” of the present invention.

  In the urging spring 100 according to the first modified example, the large coil spring 104 having a large coil diameter is less rigid in the radial direction than the small coil spring 102 having a small coil diameter, like the conical coil spring 60 described above. Therefore, when the upper end of the small coil spring 102 fixed to the valve body 50 is displaced according to the movement of the valve shaft 52, the large coil spring 104 is more easily deformed than the small coil spring 102. Then, a slight displacement on the upper end side of the small coil spring 102 is transmitted to the large coil spring 104 which is farther than the small coil spring 102 with respect to the fulcrum of the valve shaft 52, so that the large coil spring 104 is greatly deformed. Since the movement of the large coil spring 104 returning to the original state by the restoring force is transmitted to the small coil spring 102, the upper end of the small coil spring 102 can be accurately returned to the position before the displacement. Therefore, slight shake of the valve shaft 52 at the position of the valve body 50 (the upper end of the small coil spring 102) can be suppressed with high accuracy.

  FIG. 5 is a sectional view showing the shape of the biasing spring 110 installed in the gas outlet chamber 34 of the second modification. As shown in the drawing, the urging spring 110 of the second modified example is a cylindrical coil spring, but a grinding portion 112 is provided on the lower end side. In this grinding part 112, the outer peripheral side of the winding is ground, and the cross-sectional shape of the winding is semicircular. The urging spring 110 of the second modification is fixed to the valve body 50 at the upper end side where the grinding portion 112 is not provided, and is fixed to the bottom surface of the gas outlet chamber 34 at the lower end side where the grinding portion 112 is provided. The biasing spring 110 of the second modification corresponds to the “elastic body” of the present invention.

  In the urging spring 110 of the second modified example, since the cross-sectional area of the winding of the grinding portion 112 on the lower end side is about half of the winding on the upper end side, the diameter on the lower end side is larger than that on the upper end side. Directional rigidity is low. Therefore, when the upper end of the urging spring 110 fixed to the valve body 50 is displaced according to the shake of the valve shaft 52, the upper end side is not deformed and the lower end side is easily deformed. Then, a slight displacement on the upper end side of the biasing spring 110 is transmitted to the lower end side farther from the upper end side with respect to the fulcrum of the valve shaft 52, so that the lower end side is greatly deformed, and the lower end side is Since the movement of returning to the original state by the restoring force is transmitted to the upper end side, the upper end side can be accurately returned to the position before the displacement. Therefore, slight shaking of the valve shaft 52 at the position of the valve body 50 (the upper end of the biasing spring 110) can be suppressed with high accuracy.

  In the biasing spring 110 of the second modification, the grinding part 112 is provided on the lower end side. However, it is sufficient that the cross-sectional area of the winding on the lower end side is smaller than that on the upper end side, and the grinding part 112 is essential. is not. For example, a coil spring may be formed by winding a wire whose thickness on the other end side is thinner than one end side in a cylindrical shape. In this case, the thick wire side of the coil spring may be fixed to the valve body 50 and the thin wire side may be fixed to the bottom surface of the gas outlet chamber 34.

  FIG. 6 is a cross-sectional view showing the shape of the biasing spring 120 installed in the gas outlet chamber 34 of the third modification. As illustrated, the biasing spring 120 of the third modification is a cylindrical coil spring, but the number of turns per unit length (winding pitch) is different between the upper end side and the lower end side. The loosely wound portion 122 on the upper end side with a small number of turns is fixed to the valve body 50, and the densely wound portion 124 on the lower end side with a large number of turns is fixed to the bottom surface of the gas outlet chamber 34. The urging spring 120 of the third modification corresponds to the “elastic body” of the present invention.

  In the urging spring 120 according to the third modified example, the densely wound portion 124 is closer to the circumference of the winding than the loosely wound portion 122 when the winding is formed by receiving a radial force. Since the bending may be small, the densely wound portion 124 is less rigid in the radial direction than the loosely wound portion 122. Therefore, when the upper end of the urging spring 120 fixed to the valve body 50 is displaced according to the shake of the valve shaft 52, the upper end side is not deformed and the lower end side is easily deformed. Then, a slight displacement on the upper end side of the urging spring 120 is transmitted to the lower end side farther from the upper end side with respect to the fulcrum of the valve shaft 52, so that the lower end side is greatly deformed, and the lower end side is Since the movement of returning to the original state by the restoring force is transmitted to the upper end side, the upper end side can be accurately returned to the position before the displacement. Therefore, slight shake of the valve shaft 52 at the position of the valve body 50 (the upper end of the biasing spring 120) can be suppressed with high accuracy.

  Although the gas proportional valve 10 of the present embodiment and the modification has been described above, the present invention is not limited to the above embodiment and the modification, and can be implemented in various modes without departing from the gist thereof. Is possible.

  For example, in the bias springs (60, 100, 110, 120) of the above-described embodiments and modifications, the coil diameter, the cross-sectional area of the winding, Any one of the number of windings per unit length was different on one end side and the other end side, but it is not limited to one, and multiple factors are made different on one end side and the other end side. Also good.

  Further, in the gas proportional valve 10 of the above-described embodiments and modifications, various coil springs (60, 100, 110, 120) are used to bias the valve body 50. However, the present invention is not limited to the coil spring. The elastic body may be any elastic body having lower radial rigidity on the other end side than on the one end side. For example, an elastic rubber body formed into a cylindrical shape using a rubber material may be used, and in this case, the hardness of the rubber material may be different between one end side and the other end side of the elastic rubber body.

10 ... Gas proportional valve, 20 ... Main body case, 22 ... Upper case,
24 ... lower case, 26 ... lid plate, 28 ... gas inlet,
30 ... Gas inlet chamber, 32 ... Gas outlet, 34 ... Gas outlet chamber,
36 ... Valve hole, 38 ... Valve seat, 40 ... Diaphragm,
50 ... Valve body, 52 ... Valve stem, 54 ... Small diameter part,
56 ... Fastener, 60 ... Biasing spring, 70 ... Actuator,
72 ... Electromagnetic coil, 74 ... Movable iron core, 76 ... Pressing spring,
78 ... Top plate, 90 ... Coil spring, 100 ... Biasing spring,
102 ... A small coil spring, 104 ... A large coil spring, 106 ... A washer,
110: Biasing spring, 112 ... Grinding part, 120 ... Biasing spring,
122 ... sparsely wound portion, 124 ... densely wound portion.

Claims (4)

A valve seat provided with a valve hole through which a fluid passes, and the valve seat is closed by being urged by an elastic body to the valve seat, and the valve shaft is opposite to the side urged by the elastic body Projecting valve body, a diaphragm supporting the valve body at an end of the valve shaft opposite to the valve body, and an end of the valve shaft on the diaphragm side biasing force of the elastic body A drive unit that moves the valve body pressed against the valve seat in the axial direction of the valve shaft by driving against the valve seat, and passes through the valve hole according to the amount of movement of the valve body In a fluid proportional valve for controlling the flow rate of the fluid,
The fluid proportional valve, wherein the elastic body has a lower rigidity in a direction perpendicular to the valve shaft on a side farther from the valve body than on a side closer to the valve body. The fluid proportional valve according to claim 1,
The fluid proportional valve, wherein the elastic body is a coil spring having a coil diameter on a side farther from the valve body than on a side closer to the valve body. The fluid proportional valve according to claim 1 or 2,
The fluid proportional valve, wherein the elastic body is a coil spring in which a cross-sectional area of a winding farther from the valve body is smaller than a side closer to the valve body. In the fluid proportional valve according to any one of claims 1 to 3,
The fluid proportional valve, wherein the elastic body is a coil spring having a larger number of turns per unit length on a side farther from the valve body than on a side closer to the valve body.

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