JP2018059647A - Gas fuel supply device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a gas fuel supply device which can improve the adjustment accuracy of a flow rate by expanding a control range of a valve opening (by enhancing a resolution) by using a linear solenoid.SOLUTION: A fuel injection device 1 comprises a linear solenoid part 10 having: a coil 50; a fixed core 52; a movable core 54 which is sucked to the fixed core 52 by carrying electricity to the coil 50; a spring 56 for energizing the movable core 54 to a direction in which the movable core separates from the fixed core 52; and a yoke 60 for covering the coil 50. The fuel injection device adjusts a flow rate of gas fuel by changing a distance between a valve body 12 which moves together with the movable core 54 and a valve seat 14 fixed to a housing 16 by using the linear solenoid part 10. The fixed core 52 has a tapered recess 70 in which the movable core 54 is movable, and which is narrowed toward the movable core 54 side at an end part of the movable core 54 side, and a corner 81 of the movable core 54 and a corner 71 of the tapered recess 70 become the closest with respect to each other in a state that the valve body 12 abuts on a valve seat 14.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a gas fuel supply apparatus that uses a linear solenoid to adjust the flow rate of gas fuel supplied from a fuel container to a supply destination.

  As a gas fuel supply device, there is a device using a linear solenoid for adjusting the flow rate of gas fuel supplied from a fuel container to a supply destination. As a linear solenoid used in such a device, for example, there is one described in Patent Document 1. This linear solenoid includes a coil, a fixed iron core provided in the coil, and a movable iron core that is coaxially opposed to the fixed iron core, and a taper that extends toward the movable iron core at the end of the fixed iron core. A first suction part in which a concave part is formed, and an annular second suction part provided closer to the movable iron core than the first suction part, the second suction part being continuous with the side surface of the concave part A cylindrical inner peripheral surface is formed. With such a configuration, as shown in FIG. 7, the linear solenoid described in Patent Document 1 has a flat suction characteristic that is not affected by the movement displacement (stroke) of the movable iron core under a constant current.

JP 2000-277327 A

  However, when the linear solenoid is used in the gas fuel supply device, the valve opening force required for valve opening increases due to the influence of the gas load of the fuel gas. In particular, in the case of high-pressure gas fuel, the increase in valve opening force is significant. In the gas fuel supply apparatus, since the gas load of the gas fuel acts in the valve opening direction (the spring load acts in the valve closing direction), as shown in FIG. 8, the suction force Fs generated by the linear solenoid is shown. When the resultant force F of the gas load Fg exceeds the spring load Fk, the gas fuel supply device opens and gas fuel is supplied. That is, the gas fuel supply device is opened at the valve opening position shown in FIG. The spring load Fk gradually increases until the valve is fully opened after the valve is opened, and the gas load Fg gradually decreases until the valve is fully opened after the valve is opened. Then, the valve opening is fully opened at a position where the maximum value of the spring load Fk (moving displacement of the movable core 100%) and the resultant force F are equal. That is, the gas fuel supply device is fully opened at the fully opened position shown in FIG.

  In the above linear solenoid, the suction force Fs changes in proportion to the current value supplied to the coil. Therefore, when the resultant force F required at the time of valve opening increases due to the gas load Fg, a small current value is obtained after the valve is opened. It will be in the fully open state with the increase of. As described above, when the above linear solenoid is used in the gas fuel supply device, the control range (resolution) of the valve opening degree in the gas fuel supply device becomes small, and there is a problem that the flow rate control accuracy deteriorates.

  Therefore, the present invention has been made to solve the above-described problems, and the flow rate adjustment accuracy can be improved by expanding the control range of the valve opening degree by the linear solenoid (increasing the resolution). An object is to provide a gas fuel supply device.

  One form of this invention made | formed in order to solve the said subject is a coil, a fixed core, the movable core attracted | sucked by the said fixed core by the electricity supply to the said coil, and the direction which leaves | separates the said movable core from the said fixed core A linear solenoid part having a spring that biases the coil and a yoke that covers the coil, and the linear solenoid part changes a distance between a valve body that moves together with the movable core and a valve seat fixed to the housing. In the gas fuel supply apparatus that adjusts the flow rate of the gas fuel, the fixed core has a tapered recess that is movable toward the movable core and narrows toward the movable core at the end of the movable core. And the corner of the movable core and the corner of the tapered recess are closest to each other when the valve body is in contact with the valve seat.

  In this gas fuel supply device, when the valve element is in contact with the valve seat, the corner of the movable core and the corner of the tapered recess of the fixed core are closest to each other. In the valve position, the axial suction force for sucking the movable core in the axial direction can be maximized. And the fixed core is provided with the taper-shaped recessed part which can move a movable core and becomes narrow toward the movable core side in the edge part by the side of a movable core. Thereby, since the gap between the movable core and the fixed core widens as the movable core moves toward the fixed core, the suction force that the fixed core sucks the movable core decreases. Accordingly, when the value of the current applied to the coil is constant, the suction force becomes maximum at the valve opening position (when the valve is opened), and decreases as the movable core moves toward the fixed core.

  For this reason, the increase (slope) of the suction force with respect to the increase in the current value flowing through the coil can be made gentle, so even if the force required at the time of valve opening increases due to gas load, It will not be fully opened by increasing the value. That is, the increase rate of the attractive force with respect to the increase rate of the current value can be reduced as compared with the conventional case. Thereby, the control range of the valve opening degree in the gas fuel supply apparatus by the linear solenoid part is expanded (resolution is enhanced). Therefore, the flow rate adjustment accuracy in the gas fuel supply device can be improved.

  Another embodiment of the present invention made to solve the above-described problems includes a coil, a fixed core, a movable core attracted to the fixed core by energization of the coil, and the movable core from the fixed core. A linear solenoid portion having a spring that biases in a direction away from the yoke and a yoke that covers the coil is provided, and the linear solenoid portion changes a distance between a valve body that moves together with the movable core and a valve seat fixed to the housing. In the gas fuel supply device that adjusts the flow rate of the gas fuel, the movable core includes a tapered portion that is widened toward the fixed core side at an end portion on the fixed core side, and the fixed core includes the taper. The portion includes a movable recess, and the corner of the tapered portion and the corner of the recess are closest to each other in a state where the valve body is in contact with the valve seat. That.

  Even in this gas fuel supply device, when the valve element is in contact with the valve seat, the corner of the tapered portion of the movable core and the corner of the concave portion of the fixed core are closest to each other. In the valve position, the axial suction force for sucking the movable core in the axial direction can be maximized. And the movable core is equipped with the taper part which becomes wide toward the fixed core side in the edge part at the side of a fixed core. Thereby, since the gap between the movable core and the fixed core widens as the movable core moves toward the fixed core, the suction force that the fixed core sucks the movable core decreases. Accordingly, when the value of the current applied to the coil is constant, the attractive force becomes maximum at the valve opening position (when the valve is opened), and decreases as the movable core moves toward the fixed core.

  For this reason, the increase (slope) of the suction force with respect to the increase in the current value flowing through the coil can be made gentle, so even if the force required at the time of valve opening increases due to gas load, It will not be fully opened by increasing the value. That is, the increase rate of the attractive force with respect to the increase rate of the current value can be reduced as compared with the conventional case. Thereby, the control range of the valve opening degree in the gas fuel supply apparatus by the linear solenoid part is expanded (resolution is enhanced). Therefore, the flow rate adjustment accuracy in the gas fuel supply device can be improved.

  In the gas supply apparatus described above, the spring constant of the spring is increased within a range that does not exceed the force required to move the movable core in the valve opening direction, thereby allowing the movable core to move with respect to the displacement of the movable core. The rate of increase in spring load by the spring acting on the core may be close to the rate of increase in force required to move the movable core.

  By doing so, the spring load acting on the movable core when the displacement of the movable core reaches the maximum (100%), that is, the maximum value of the spring load is increased. In the fully open position, the maximum value of the spring load (the spring load when the moving displacement of the movable core is 100%) and the force necessary to move the movable core (the resultant force of the suction force and the gas load) are equal. Therefore, the resultant force at the fully open position increases. Accordingly, the displacement of the movable core is increased. Thereby, since the fully open position can be made a position further away from the valve opening position, the control range of the valve opening degree in the gas fuel supply device by the linear solenoid part can be further expanded (resolution is increased). Therefore, the flow rate adjustment accuracy in the gas fuel supply device can be further improved.

  According to the gas fuel supply device of the present invention, the control range of the valve opening degree by the linear solenoid unit is expanded (resolution is increased), so that the flow rate adjustment accuracy can be improved.

It is sectional drawing of the fuel-injection apparatus in 1st Embodiment. It is a figure which shows the attractive force characteristic of the linear solenoid part in 1st Embodiment. It is a figure which shows the control range of the valve opening degree in a fuel injection apparatus. It is sectional drawing of the fuel-injection apparatus in 2nd Embodiment. It is a figure which shows the attractive force characteristic of the linear solenoid part in 2nd Embodiment. It is sectional drawing of the fuel-injection apparatus in the modification of 2nd Embodiment. It is a figure which shows the attraction force characteristic of the linear solenoid of a prior art example. It is a figure which shows the control range of the valve opening degree in the fuel-injection apparatus to which the linear solenoid of a prior art example is applied.

<First Embodiment>
In the present embodiment, a case where the gas fuel supply device of the present invention is applied to a fuel injection device (injector) will be described. This fuel injection device is a device for supplying gas fuel (for example, hydrogen) to a fuel cell (not shown) in a fuel cell vehicle, for example. Therefore, first, the first embodiment will be described.

  As shown in FIG. 1, the fuel injection device 1 according to the first embodiment includes a linear solenoid unit 10, a valve body 12, a valve seat 14, a housing 16, and the like.

  The linear solenoid unit 10 includes a coil 50, a fixed core 52, a movable core 54, a compression spring 56, bearings 58 and 59, a yoke 60, and the like. The coil 50 is formed by winding a conducting wire around a hollow cylindrical coil bobbin 51. A fixed core 52 and a movable core 54 are disposed in the hollow portion of the coil bobbin 51.

  The fixed core 52 is disposed at one end of the coil bobbin 51. The fixed core 52 is formed in a substantially cylindrical shape (including a true cylindrical shape or an elliptical cylindrical shape), and includes a tapered concave portion 70 and a bearing holding concave portion 74. The tapered recess 70 is a recess that is formed in a tapered shape that allows the movable core 54 to move and narrows toward the movable core 54, and has a larger diameter than the bearing holding recess 74. A bearing 58 is disposed inside the bearing holding recess 74. The fixed core 52 is made of a soft magnetic material (for example, electromagnetic stainless steel).

  The movable core 54 is formed in a substantially cylindrical shape (including a true cylindrical shape or an elliptical cylindrical shape), and includes a cylindrical portion 80, a shaft portion 84, and a valve body portion 86. The movable core 54 is made of a soft magnetic material (for example, electromagnetic stainless steel). In the movable core 54, a part of the cylindrical portion 80 and the valve body portion 86 are disposed in the housing 16, and the shaft portion 84 is disposed in the bearing 58. Further, the cylindrical portion 80 and the shaft portion 84 are located in the hollow portion of the coil bobbin 51. In the state where the valve body 12 is in contact with the valve seat 14 (the state shown in FIG. 1), the movable core 54 has a cylindrical portion 81 that is a corner of the cylindrical portion 80 at a corner of the tapered recess 70. It is closest to a certain concave corner 71.

  The movable core 54 has a shaft portion 84 slidably supported by the bearing 58 at one end and a valve body 86 slidably supported by the bearing 59 at the other end. Thereby, the movable core 54 is configured such that the end portion of the cylindrical portion 80 moves in the tapered concave portion 70 on the fixed core 52 side. Further, the valve body 12 is integrally formed at the end of the valve body portion 86, and the valve body 12 moves with the movement of the movable core 54.

  The compression spring 56 is disposed inside the bearing 58 and between the fixed core 52 and the movable core 54. The compression spring 56 is in a compressed state and urges the valve body 12 (movable core 54) toward the valve seat 14. That is, the spring load Fk acts on the movable core 54 in the valve closing direction by the compression spring 56 (see FIG. 3).

  The yoke 60 is disposed so as to surround the coil 50. A lid member 62 is disposed in the opening portion of the yoke 60. The yoke 60 and the lid member 62 are made of a soft magnetic material (for example, electromagnetic stainless steel) and constitute a cover of the linear solenoid unit 10.

  The valve body 12 is integrally formed at the end of the valve body portion 86 of the movable core 54. The valve body 12 is disposed upstream of the valve seat 14 in the gas fuel flow direction. The valve body 12 includes a substantially disc-shaped seal member 13 on an end surface thereof. The seal member 13 is a portion that contacts / separates from the valve seat 14 (seat portion 15). The seal member 13 is formed of an elastic body such as rubber or resin.

  The valve seat 14 is fixed to the housing 16 and includes a seat portion 15 whose outer side is formed in a tapered shape. The seal member 13 of the valve body 12 abuts against the seat portion 15 while being elastically deformed, so that the sealing performance when the supply of gas fuel is stopped (when the valve is closed) is secured. The valve seat 14 is disposed downstream of the valve body 12 in the gas fuel flow direction. A discharge hole 22 is formed in the central portion of the valve seat 14. The discharge hole 22 is a hole penetrating the valve seat 14 in the axial direction, and is a gas fuel flow path. The discharge hole 22 is connected to a supply destination (for example, a fuel cell) via a fuel pipe.

  The housing 16 is formed in a substantially cylindrical shape, and accommodates the valve body 12 (a part of the movable core 54), the valve seat 14, the bearing 59, and the like. The housing 16 is made of a soft magnetic material (for example, electromagnetic stainless steel). A fuel flow path 18 through which gas fuel flows is formed inside the housing 16. The housing 16 includes an inflow hole 20 that communicates with the fuel flow path 18 from the side. The inflow hole 20 is a hole penetrating the housing 16 in the radial direction, and is a gas fuel flow path. The inflow hole 20 is connected to a fuel container (for example, a hydrogen cylinder) via a fuel pipe.

  A part of the housing 16 (portion that accommodates the cylindrical portion 80 of the movable core 54) is disposed at the other end (the side opposite to the fixed core 52) of the hollow portion of the coil bobbin 51. An annular member 64 that is a nonmagnetic material is disposed between the end of the housing 16 and the end of the fixed core 52.

  Next, the operation (operation) of the fuel injection device 1 will be described. First, when the coil 50 is not energized, that is, when the valve is closed, the sealing member 13 of the valve body 12 is moved by the urging force of the compression spring 56 as shown in FIG. Abut. At this time, the gas load Fg of the fuel gas is acting on the movable core 54 in the valve opening direction, but the spring load Fk by the compression spring 56 larger than the gas load Fg is acting in the valve closing direction (see FIG. 3). ). Therefore, the discharge hole 22 of the valve seat 14 is blocked from the fuel flow path 18. Therefore, the gas fuel is not released from the discharge hole 22 to the outside of the fuel injection device 1.

  On the other hand, when the coil 50 is energized, that is, when the valve is opened, the magnetic flux flows around the coil 50 through the yoke 60, the housing 16, the movable core 54, the fixed core 52, and the lid member 62. A magnetic circuit returning to is formed. Therefore, a suction force that causes the fixed core 52 to suck the movable core 54 is generated. Due to this suction force, the movable core 54 moves to the fixed core 52 side. Therefore, the seal member 13 of the valve body 12 is separated from the seat portion 15 of the valve seat 14. Thereby, the discharge hole 22 of the valve seat 14 communicates with the fuel flow path 18.

  Specifically, the discharge hole 22 communicates with the fuel flow path 18 through a gap between the seal member 13 of the valve body 12 and the seat portion 15 of the valve seat 14. Therefore, the gaseous fuel flowing in the fuel flow path 18 flows into the discharge hole 22 through the gap between the seal member 13 and the seat portion 15. Thereby, the gas fuel is discharged from the discharge hole 22 to the outside of the fuel injection device 1. At this time, the amount of movement of the movable core 54 (valve body 12) changes according to the value of the current flowing through the coil 50. Therefore, by controlling the value of the current flowing through the coil 50, the valve opening of the fuel injection device 1 can be adjusted to control the amount of gas fuel supplied.

  Here, in the fuel injection device 1, when energization of the coil 50 is started, that is, when the valve opening is started, the cylindrical corner portion 81 and the concave corner portion 71 are closest to each other. As a result, when the current value supplied to the coil 50 is constant, the magnetic attractive force generated by the magnetic circuit is maximized at the valve opening position as shown in FIG.

  The fixed core 52 is formed with a tapered recess 70 that narrows toward the movable core 54 side. For this reason, the gap between the movable core 54 and the fixed core 52 increases as the movable core 54 moves toward the fixed core 52, so that the suction force that the fixed core 52 sucks the movable core 54 decreases. Therefore, when the value of the current supplied to the coil 50 is constant, the attractive force becomes maximum at the valve opening position (when the valve is opened), and decreases as the movable core 54 moves to the fixed core 52 side. It has become.

  Therefore, in the fuel injection device 1, as shown in FIG. 3, the increase (inclination) of the attractive force Fs with respect to the increase in the current value is moderate as compared with the conventional example (see FIG. 8). The spring load Fk and the gas load Fg acting on the movable core 54 are the same as in the conventional example. Therefore, during the valve opening operation, the increase (slope) of the resultant force F with respect to the increase in the current value is also gentler than in the conventional example. That is, the increase rate of the resultant force F with respect to the increase rate of the current value can be reduced as compared with the conventional example. The resultant force F is a force required to move the movable core 54 and is a resultant force of the suction force Fs that the fixed core 52 sucks the movable core 54 and the gas load Fg.

  Thereby, according to the fuel-injection apparatus 1, after opening a valve, it can avoid that it will be in a full open state by a slight increase in electric current value like a prior art example. As a result, the control range of the valve opening degree in the fuel injection device 1 by the linear solenoid unit 10 is expanded more than twice (the resolution is increased), so that the flow rate adjustment accuracy in the fuel injection device 1 is improved.

  Here, by increasing the spring constant of the compression spring 56 within a range not exceeding the resultant force F necessary for moving the movable core 54 in the valve opening direction, it acts on the movable core 54 with respect to the movement displacement of the movable core 54. The increase rate of the spring load Fk by the compression spring 56 may be close to the increase rate of the resultant force F necessary to move the movable core 54. That is, the spring constant of the compression spring 56 may be increased, and the inclination of the spring load Fk may be increased so as to approach the resultant force F as indicated by a broken line in FIG.

  By doing so, the spring load Fk acting on the movable core 54 when the stroke of the movable core 54 reaches the maximum (100%), that is, the maximum value of the spring load Fk is increased. And since the full open position becomes a position where the maximum value of the spring load Fk and the resultant force F become equal, the resultant force F in the fully opened position increases. As a result, since the stroke amount of the movable core 54 is increased, the fully opened position can be set further away from the valve opening position. Thereby, the control range of the valve opening degree in the fuel injection device 1 by the linear solenoid unit 10 can be further expanded (resolution is increased). Therefore, the flow rate adjustment accuracy in the fuel injection device 1 can be further improved.

  As described above in detail, according to the fuel injection device 1 according to the present embodiment, the fixed core 52 is provided with the tapered concave portion 70 that narrows toward the movable core 54 at the end on the movable core 54 side. Therefore, the increase rate of the attractive force with respect to the increase rate of the current value can be reduced as compared with the conventional case. Thereby, since the control range of the valve opening degree in the fuel injection device 1 by the linear solenoid unit 10 is expanded (resolution is increased), the adjustment accuracy of the flow rate can be improved.

Second Embodiment
Next, the second embodiment will be described with reference to FIG. 4, but the same components as those in the first embodiment will be denoted by the same reference numerals, the description thereof will be omitted, and different points will be mainly described. .

  In the fuel injection device 101 of the present embodiment, as shown in FIG. 4, the shape of the movable core 154 is different from that of the first embodiment. Specifically, the movable core 154 includes a tapered portion 180 that widens toward the fixed core 52 side at the end of the cylindrical portion 80 on the fixed core 52 side. The movable core 154 has a tapered corner portion 181 which is a corner portion of the tapered portion 180 when the valve body 12 is in contact with the valve seat 14 (the state shown in FIG. 4). 71 is closest.

  In such a fuel injection device 101, the taper portion corner portion 181 and the recess corner portion 71 are closest to each other when the energization of the coil 50 is started, that is, when the valve opening is started. Thereby, when the current value supplied to the coil 50 is constant, the magnetic attractive force generated by the magnetic circuit is maximized at the valve opening position as shown in FIG.

  The movable core 154 has a tapered portion 180 that is widened toward the fixed core 52 side at the end of the cylindrical portion 80 on the fixed core 52 side. A tapered recess 70 that narrows toward the bottom is formed. Therefore, as the movable core 154 moves to the fixed core 52 side, the gap between the movable core 154 and the fixed core 52 becomes wider than in the first embodiment, so that the suction force that the fixed core 52 sucks the movable core 154 is the first. This is further reduced than in the first embodiment. Therefore, when the value of the current supplied to the coil 50 is constant, the suction force is maximized at the valve opening position (when the valve is opened), and as compared with the first embodiment as the movable core 154 moves toward the fixed core 52 side. It has a characteristic of decreasing greatly (inclination increasing).

  Therefore, in the fuel injection device 101, the increase (slope) of the attractive force Fs with respect to the increase in the current value is further gentler than that in the first embodiment. Therefore, during the valve opening operation, the increase (slope) of the resultant force F with respect to the increase in the current value is further gentler than that in the first embodiment. That is, the increase rate of the resultant force F with respect to the increase rate of the current value can be made smaller than in the first embodiment.

Therefore, according to the fuel injection device 101, the control range of the valve opening degree in the fuel injection device 101 by the linear solenoid unit 10 is further expanded (the resolution is increased), so that the flow rate adjustment accuracy in the fuel injection device 101 is further increased. improves.
Similarly to the first embodiment, the control range of the valve opening in the fuel injection device 101 is further expanded by increasing the spring constant of the compression spring 56 and increasing the slope of the spring load Fk (resolution). Can be increased). As a result, the flow rate adjustment accuracy in the fuel injection device 101 can be further improved.

  It should be noted that the above-described embodiment is merely an example, and does not limit the present invention in any way, and various improvements and modifications can be made without departing from the scope of the invention. For example, in the second embodiment, the concave portion on the movable core 154 side of the fixed core 52 is a tapered concave portion 70 formed in a tapered shape whose inner diameter gradually changes, but the inner diameter does not change as shown in FIG. A recess 170 having a constant inner diameter may also be used. In this case, since the suction force characteristics are the same as those in the first embodiment, the control range of the valve opening is as large as that in the first embodiment.

  The fuel injection device described above can also be applied to gas fuels other than hydrogen (for example, CNG). Furthermore, in the above-described embodiment, the case where the flow of gas fuel flows from the inflow hole 20 to the discharge hole 22 via the fuel flow path 18 is described, but the flow of gas fuel is reversed, that is, the flow of fuel from the discharge hole 22. The present invention can also be applied to the case of flowing into the inflow hole 20 through the path 18.

DESCRIPTION OF SYMBOLS 1 Fuel injection apparatus 10 Linear solenoid part 12 Valve body 13 Seal member 14 Valve seat 15 Seat part 16 Housing 50 Coil 52 Fixed core 54 Movable core 56 Compression spring 58 Bearing 59 Bearing 60 Yoke 70 Tapered recessed part 71 Recessed corner part 80 Cylindrical part 81 Cylindrical corner

Claims (3)

Linear including a coil, a fixed core, a movable core that is attracted to the fixed core by energizing the coil, a spring that biases the movable core in a direction away from the fixed core, and a yoke that covers the coil In a gas fuel supply device comprising a solenoid part, and adjusting a flow rate of gas fuel by changing a distance between a valve body moving together with the movable core and a valve seat fixed to the housing by the linear solenoid part,
The fixed core includes, at an end portion on the movable core side, a tapered recess that is movable toward the movable core side and narrows toward the movable core side,
The gas fuel supply device, wherein a corner of the movable core and a corner of the tapered recess are closest to each other in a state where the valve body is in contact with the valve seat. Linear including a coil, a fixed core, a movable core that is attracted to the fixed core by energizing the coil, a spring that biases the movable core in a direction away from the fixed core, and a yoke that covers the coil In a gas fuel supply device comprising a solenoid part, and adjusting a flow rate of gas fuel by changing a distance between a valve body moving together with the movable core and a valve seat fixed to the housing by the linear solenoid part,
The movable core includes a taper portion that widens toward an end of the fixed core toward the fixed core,
The fixed core includes a recess in which the tapered portion is movable,
The gas fuel supply device, wherein a corner portion of the tapered portion and a corner portion of the concave portion are closest to each other in a state where the valve body is in contact with the valve seat. In the gas fuel supply device according to claim 1 or 2,
The spring load of the spring acting on the movable core with respect to the displacement of the movable core by increasing the spring constant of the spring within a range not exceeding the force required to move the movable core in the valve opening direction. The gas fuel supply device is characterized in that the increase rate of the gas is close to the increase rate of the force required to move the movable core.

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