JP2019086210A - Gas valve device - Google Patents

Abstract

To achieve power saving by avoiding useless power consumption in a gas valve device which is provided with a flow control valve 3 having a valve body 32 driven with a motor 4 via an interlock mechanism 5, controls the motor when instruction fire power is changed to a decrease side, on the basis of normal rotation flow characteristics when decreasing a gas flow rate by normal rotation of the motor, and controls the motor when instruction fire power is changed to an increase side, on the basis of reverse rotation flow characteristics when increasing the gas flow rate by reverse rotation of the motor, set by shifting the rotation phase of the motor in a reverse direction only for hysteresis to the normal rotation flow characteristics.SOLUTION: The rotation of a motor 4 is stopped when instruction fire power is previously changed to one of a decrease side and an increase side followed by being changed this time to the other of a decrease side and an increase side, and fire power change is suddenly cancelled and instruction fire power is returned to the previous fire power before changing in the middle of the angle rotation for hysteresis of the motor 4.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a gas valve device interposed in a gas supply path to a burner, and in which a flow control valve having a valve body driven by a motor via a linkage mechanism is provided in a valve casing. .

  In this type of gas valve device, assuming that the rotation direction of the motor for moving the valve body in the direction of decreasing the gas flow rate is the normal direction, and the rotation direction of the motor for moving the valve body in the direction of increasing the gas flow rate is the reverse direction. The rotational phase of the motor when the valve body is moved to the same position by rotation of the motor in the normal direction and the rotational phase of the motor when it is moved by the rotation of the motor in the reverse direction differ due to the influence of the play of the interlocking mechanism It becomes a phase. Therefore, conventionally, when the valve body is moved to the same position by rotating the motor in the forward direction of rotation and when it is moved by rotating the motor in the reverse direction of rotation, the motor rotational phase difference is used as hysteresis. The indicated thermal power indicated by the operation of the thermal power indication member is changed to the decrease side based on the flow characteristics at the time of normal rotation showing the relationship between the rotational phase of the motor and the gas flow rate when decreasing the gas flow rate by rotation in the direction Control of the motor at the same time, and the rotational phase of the motor is shifted in the reverse direction by the hysteresis with respect to the forward flow rate characteristic, the motor when increasing the gas flow rate by the reverse rotation of the motor The control of the motor when the designated thermal power is changed to the increase side is performed based on the reverse flow rate characteristic representing the relationship between the rotational phase and the gas flow rate (for example, see Patent Document 1).

  In this case, when the indicated thermal power is changed to one of the decrease side and the increase side last time and then changed to the other of the decrease side and the increase side this time, first, the motor rotates by an angle of hysteresis and the motor The relationship between the rotational phase and the gas flow rate is switched from one flow rate characteristic during forward rotation and reverse flow rate to the other flow rate characteristic, and then control of the motor is performed according to the other flow rate characteristic. By the way, since the indicated thermal power is changed to one of the decrease side and the increase side last time, it is changed to the other of the decrease side and the increase side this time, and the thermal power change is sudden while the motor rotates by an angle for hysteresis. It may be canceled and the indicated firepower may be returned to the original firepower. In this case, conventionally, the motor is rotated back to the phase stopped at the previous change of the thermal power and then stopped.

  Here, if the rotation angle of the motor is within the angle range of the hysteresis, the valve body is not displaced and the gas flow rate does not change. Therefore, when the motor is returned and rotated as described above, power is consumed wastefully while the gas flow rate does not change.

JP, 2014-115040, A

  In view of the above points, the present invention has an object to provide a gas valve device that can save power by avoiding unnecessary power consumption.

  In order to solve the above problems, the present invention is a gas valve device interposed in a gas supply path to a burner, and a flow rate having a valve body driven by a motor via a linkage mechanism in a valve casing. A control valve is provided, and the valve body is moved in the direction in which the gas flow rate decreases. The rotation direction of the motor in the direction in which the gas flow rate increases is the reverse direction. The difference between the rotational phase difference of the motor between the same position when moving the motor in the normal rotation direction and the movement position of the motor in the reverse direction is the hysteresis. Control of the motor when the indicated thermal power indicated by the operation of the thermal power indication member is changed to the decrease side based on the flow characteristics at the time of normal rotation showing the relationship between the rotational phase of the motor and the gas flow rate when decreasing Do In both cases, the rotational phase of the motor is shifted in the reverse direction by the hysteresis amount with respect to the forward flow rate characteristic, and the rotational phase of the motor and the gas flow rate are increased when the gas flow rate is increased by the reverse rotation of the motor. In the control of the motor when the indicated thermal power is changed to the increase side based on the reverse flow rate characteristics representing the relationship, the indicated thermal power is decreased to the current decrease side since it was changed to the previous decrease side or the increase side. And the increase side is changed to the other, when the motor power change is suddenly canceled and the commanded heat power is returned to the power before the change while the motor is rotating at an angle for the hysteresis angle, the motor at that time To stop the rotation of.

  According to the present invention, when the thermal power change is suddenly canceled before the valve body is displaced within the angle range of the motor rotation angle within the angle range for hysteresis, the motor rotation is stopped at that point, so wasteful power is consumed. It is possible to save power by avoiding consumption. In this case, when the designated thermal power is changed next, control of the motor may be performed in consideration of the motor rotation angle until the rotation is stopped.

  By the way, when the instructed thermal power becomes the minimum thermal power, the motor is rotated in the forward rotation direction to a predetermined minimum thermal power phase corresponding to the minimum thermal power determined based on the flow rate characteristic at normal rotation. However, if slippage with the motor occurs due to jamming in the interlocking mechanism, etc., even if the motor is rotated to the minimum heating power phase, the valve body is not displaced to the position where the gas flow rate is minimized, and the heating power is larger than the minimum heating power. Sometimes it becomes. Therefore, while providing a detector in the component members of the interlocking mechanism, the motor rotates in the normal rotation direction from the phase corresponding to the thermal power one stage higher than the minimum thermal power determined based on the flow characteristic at normal rotation A position sensor for detecting the displacement of the detector to the detection range is provided with the position range where the detector is present as the detection range when it is in the rotation range from the predetermined phase before this to the minimum firepower phase. It is desirable that the position sensor output a detection signal (a signal indicating that the detector has been displaced to the detection range) so as to ensure that the thermal power is the minimum.

  However, while the indicated thermal power is changed from the minimum thermal power to the increase side, the thermal power is changed while the motor is rotating in the reverse direction from the minimum thermal power phase to the phase corresponding to the minimum thermal power determined based on reverse flow rate characteristics. Is suddenly canceled and the designated thermal power is returned to the minimum thermal power, the detector may be displaced out of the detection range, and the position sensor may not output the detection signal. In this case, if the rotation of the motor is stopped at the time of cancellation of the thermal power change, the position sensor will not output the detection signal even if the actual thermal power is the minimum thermal power, and it can not be guaranteed that the thermal power is the minimum.

  Therefore, the indicated thermal power is changed from the minimum thermal power to the increase side, and while the motor is rotating in the reverse direction from the minimum thermal power phase to the phase corresponding to the minimum thermal power determined based on the reverse flow rate characteristics, When it is suddenly canceled and the commanded thermal power is returned to the minimum thermal power, it is desirable to rotate the motor in the forward direction to the minimum thermal power phase without stopping the rotation of the motor. According to this, even if the detection element is displaced out of the detection range at the time of cancellation of the thermal power change and the position sensor does not output the detection signal, the detection element is displaced to the detection range by the rotation of the motor up to the minimum thermal phase. Thus, the position sensor can output a detection signal to guarantee that the power is minimum.

The cut side view of the gas valve device of the embodiment of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS The perspective view of the gas valve apparatus of embodiment. The perspective view of the decomposition | disassembly state of the interlocking mechanism provided in the gas valve apparatus of embodiment. (A) (b) (c) Cutaway side view of the principal part which shows operation of the gas valve device of an embodiment. The side view which shows the relationship between the detector of the gas valve apparatus of embodiment, and a position sensor. The graph which shows the flow-rate characteristic at the time of normal rotation in the gas valve device of an embodiment, and the flow characteristic at the time of reverse rotation.

  With reference to FIGS. 1 and 2, the gas valve device according to the embodiment of the present invention is interposed in a gas supply passage GS to a burner B for a stove, and includes a cylindrical valve casing 1 and a valve. The electromagnetic safety valve 2 disposed on the one axial side in the casing 1, the flow control valve 3 disposed in series with the electromagnetic safety valve 2 on the other axial side in the valve casing 1, and the other axial direction of the valve casing 1 Operation which is inserted from the other side in the axial direction into the valve casing 1 from the motor 4 consisting of a stepping motor mounted on the outer end of the box 11 attached to the end of the box 11 and axially driven by the motor 4 via the interlocking mechanism 5 The rod 6 is provided. In the following description, one axial direction is referred to as a forward movement direction, and the other axial direction is referred to as a backward movement direction.

  In the valve casing 1, a gas inlet 1 a located on the upstream side of the electromagnetic safety valve 2 and a gas outlet 1 b located on the downstream side of the flow control valve 3 are opened. Then, when the electromagnetic safety valve 2 is opened, gas flows from the gas inlet 1 a to the gas outlet 1 b, and the gas is supplied to the burner B. A pan bottom temperature sensor Ba which abuts on the bottom surface of the cooking vessel is attached to the burner B.

  The electromagnetic safety valve 2 includes a valve seat 21 facing in the forward movement direction, a valve body 22 facing the valve seat 21, a valve spring 23 urging the valve body 22 in the backward movement direction and seating on the valve seat 21; An adsorption piece 24 connected to the body 22 via a valve shaft 22a extending in the forward movement direction, and an electromagnet 25 opposed to the adsorption piece 24 are provided. Then, the valve body 22 is attracted and held at the valve opening position by energizing the electromagnet 25 in a state in which the valve body 22 is pushed against the valve spring 23 to the valve opening position where the attraction piece 24 abuts the electromagnet 25. To be done. Also, when a misfire is detected by a flame detection element (not shown) attached to the burner B, the energization of the electromagnet 25 is stopped, and the valve body 22 is at the valve closed position where it is seated on the valve seat 21 by the valve spring 23. The valve is returned to close the electromagnetic safety valve 2 to prevent the flow of gas.

  The valve seat 21 of the solenoid safety valve 2 is formed on the end face of the valve seat member 7 movable in the axial direction with respect to the valve casing 1 provided in the valve casing 1. Further, the valve casing 1 comprises a projection formed on the inner surface of the valve casing 1 for stopping the movement of the valve seat member 7 in the backward direction at a predetermined position where the valve body 22 of the electromagnetic safety valve 2 can be seated. A valve seat stopper 71 and a valve seat spring 72 resiliently urging the valve seat member 7 in the backward direction and holding the valve seat member 7 in the predetermined position are provided. In addition, in order to prevent the flow of gas to the outside of the valve seat member 7, a veloff ram 73 is provided.

  The flow rate control valve 3 includes a valve seat 31 formed in the valve seat member 7 so as to face the return direction, and a valve body 32 fixed to the forward movement direction end of the operation rod 6. The valve body 32 has a closing valve portion 321 that can be seated on the valve seat 31 so as to close the valve hole 31a opened in the valve seat 31, a needle portion 322 that can be inserted into the valve hole 31a from the return direction, It has a bypass passage 323 which constantly communicates the upstream side and the downstream side of the valve 3. In the present embodiment, the valve body 32 is integrally formed with the operating rod 6, but the valve body 32 may be attached to the operating rod 6 as a separate body from the operating rod 6.

  Referring to FIGS. 1 and 3, interlocking mechanism 5 includes a reduction gear train 51 incorporated in the case of motor 4, a rotation shaft 52 rotationally driven by motor 4 via reduction gear train 51, and a rotation shaft In the cylindrical cam body 54 concentric with the operation rod 6 and coupled to the rotary shaft 52 via the connector 53 so as to rotate interlockingly with 52, and the spiral cam groove 541 formed in the cam body 54 The operating rod 6 is moved by an axial thrust that is engaged with the pin 55 fixed to the operating rod 6 and acts from the cam groove 541 through the pin 55 by rotation of the cam body 54 in one direction and the other direction. It is made to move in the movement direction and the return direction.

  The connector 53 has a non-circular hole 531 fitted to the rotating shaft 52 having a non-circular cross section, and rotates together with the rotating shaft 52. Further, the connector 53 is provided with a projecting piece 532 that transmits a rotational force by engaging with a notch 542 formed at the end of the cam 54 in the backward movement direction. A guide cylinder 56 extending in the backward direction from the valve casing 1 is inserted into the cam body 54. The guide cylinder 56 is formed with a long hole 561 which is long in the axial direction, and the pin 55 is slidably engaged with the long hole 561 in the axial direction.

  According to the above configuration, when the motor 4 is rotated in one direction, the operating rod 6 is moved through the interlocking mechanism 5, that is, the reduction gear train 51, the rotating shaft 52, the connector 53, the cam 54 and the pin 55. The valve body 32 of the flow control valve 32 first contacts the valve seat 31 for the flow control valve of the valve seat member 7 located at a predetermined position that is stopped by the valve seat stopper 71. Thereafter, the valve seat member 7 is pushed by the valve body 32 for the flow rate adjustment valve to move in the forward movement direction, and the valve body 22 for the safety valve is pushed to the valve opening position via the valve seat member 7 The state shown to Fig.4 (a)). In this state, the electromagnet 25 is energized to attract and hold the valve body 22 at the valve opening position, and then the motor 4 is rotated in the other direction to reciprocate the operating rod 6, ie, the valve body 32 for the flow control valve. Move in the direction. At this time, the valve seat member 7 moves in the backward direction following the valve body 32 by the biasing force of the valve seat spring 72 to a predetermined position that is stopped by the valve seat stopper 71, and the valve seat 21 for the safety valve is opened. The electromagnetic safety valve 2 is opened apart from the valve body 22 adsorbed and held at the valve position. When the valve body 32 for the flow control valve is further moved in the backward direction with respect to the valve seat member 7 stopped in the predetermined position, the closing valve portion 321 is separated from the valve seat 31 for the flow control valve and the needle portion 322 is a valve The gas flow rate gradually increases as the holes 31a gradually exit. After that, the valve body 32 for the flow rate control valve moves in the forward movement direction and the valve for the flow rate control valve in a state where the valve seat member 7 is in the predetermined position stopped by the valve seat stopper 71 The position where the closing valve portion 321 is seated on the seat 31 (the state of FIG. 4B) and the position immediately before the valve seat 21 for the safety valve abuts on the valve body 22 for the safety valve existing in the valve opening position (FIG. In the range between the condition c) and the condition c), the gas flows only through the bypass passage 323, and the gas flow rate is maintained at the minimum amount. In the following description, the direction in which the gas flow rate decreases, that is, the rotation direction of the motor 4 for moving the valve body 32 for the flow control valve in the forward direction is the normal direction, and the direction in which the gas flow rate increases. That is, the rotational direction of the motor 4 moved in the backward direction is referred to as the reverse direction.

  It is difficult to controlly stop the motor 4 at the moment when the valve element 22 for the safety valve reaches the valve opening position, that is, at the moment when the attraction piece 24 abuts against the electromagnet 25. Therefore, when the operation rod 6 is pushed in the forward direction through the interlocking mechanism 5 by further rotation of the motor 4 in the forward rotation direction after the valve body 22 reaches the valve opening position, the attraction piece 24 and the electromagnet 25 An excessive force may be applied to the contact portion of the contact piece, and the suction piece 24 may be scratched to cause a suction failure.

  Therefore, in the present embodiment, a cam stopper 57 constituted by an end plate of the box 11 which makes the cam body 54 movable in the axial direction and stops the movement of the cam body 54 in the forward direction at a predetermined position; A cam spring 58 is provided to bias the cam body 54 in the forward movement direction. The cam body 54 is a cam spring due to an axial reaction force acting from the pin 55 through the cam groove 541 by further rotation of the motor 4 in the forward rotation direction after the valve element 22 for the safety valve reaches the valve opening position. It is designed to move in the backward direction against the biasing force of 58. According to this, even if the motor 4 is further rotated in the forward rotation direction after the valve element 22 for the safety valve reaches the valve opening position, an excessive force is not applied to the contact portion between the attraction piece 24 and the electromagnet 25. It is possible to prevent the occurrence of a suction failure due to the scratch of the suction piece 24. In addition, before the valve element 22 for the safety valve reaches the valve opening position, the cam spring 58 is prevented from losing the biasing force of the valve spring 23 and the valve seat spring 72 and moving the cam body 54 in the backward direction. The biasing force is set to be slightly larger than the resultant force of the biasing forces of the valve spring 23 and the valve seat spring 72.

  Referring to FIG. 6, line a represents the rotational phase of the motor 4 and the gas when the valve element 32 for the flow rate control valve is moved in the forward direction by rotation of the motor 4 in the normal direction to reduce the gas flow rate. The normal flow rate characteristic representing the relationship with the flow rate is shown, and the line b indicates the rotation of the motor 4 when moving the valve element 32 for the flow rate control valve in the backward direction by reverse rotation of the motor 4 to increase the gas flow rate. The reverse flow rate characteristic representing the relationship between the phase and the gas flow rate is shown. Here, the rotational phase difference between the motor 4 when moving the valve element 32 for the flow rate control valve to the same axial position by rotation of the motor 4 in the normal rotation direction and when moving it by rotation of the motor 4 in the reverse rotation direction. This hysteresis H represents the play of the reduction gear train 51, the play between the rotary shaft 52 and the connector 53, the play between the connector 53 and the cam body 54, the cam groove 541 and the pin 55 And the play between the pin 55 and the long hole 561 correspond to the total play. The reverse flow rate characteristic is obtained by shifting the rotational phase of the motor 4 in the reverse rotational direction by the hysteresis H with respect to the forward flow rate characteristic.

  When the indicated thermal power indicated by the operation of the thermal power indication member (not shown) provided in the stove operation unit is changed to the decrease side and the motor 4 is rotated in the forward direction to reduce the gas flow rate, When the motor 4 is controlled based on the flow rate characteristics and the command thermal power is changed to the increase side to reverse the motor 4 to increase the gas flow rate, the motor 4 is controlled based on the reverse flow rate characteristics. Furthermore, when the indicated thermal power is changed to one of the decrease side and the increase side last time and then changed to the other of the decrease side and the increase side this time, first, the motor 4 rotates by an angle of hysteresis H, The relationship between the rotational phase of 4 and the gas flow rate is switched from one flow rate characteristic at the time of forward rotation to that at reverse rotation to the other flow rate characteristic, and then the control of the motor 4 is performed according to the other flow rate characteristic.

  Specifically, in the present embodiment, the thermal power (gas flow rate) is variably adjusted in five stages from the first thermal power Q1 which is the smallest to the fifth thermal power Q5 which is the largest. Are determined based on the rotational phases θ 4 n to θ 1 n corresponding to the fourth, third, second and first thermal powers Q 4 to Q 1 and the flow characteristics at reverse The rotational phases θ2r to θ5r corresponding to the fourth and fifth thermal powers Q2 to Q5 are stored in a controller (not shown). Here, θ2r = θ2n−H, θ3r = θ3n−H, θ4r = θ4n−H. Then, in the case of reducing the command thermal power to any of the fourth to first thermal power Q4 to Q1, the motor 4 is rotated in the forward rotation direction, and when the rotational phase becomes any of θ4n to θ1n, the motor When 4 is stopped and the commanded thermal power is increased to any of the second to fifth thermal powers Q2 to Q5, the motor 4 is rotated in the reverse direction and the rotational phase becomes any of θ2r to θ5r. Stop the motor 4

  Note that the minimum thermal power phase θ1n corresponding to the first thermal power Q1 determined based on the forward flow rate characteristic is the position at which the valve element 32 for the flow rate control valve is shown in FIG. The phase is set to be displaced to a predetermined position between the positions shown in c). Therefore, the phase θ1r corresponding to the first thermal power Q1 determined based on the reverse flow rate characteristics (phase when the valve body 32 is displaced to the position shown in FIG. 4B by the reverse rotation of the motor 4) And the minimum thermal power phase θ1 n is larger than the hysteresis H. Further, the motor 4 of the present embodiment is a stepping motor, and the rotational phase of the motor 4 is determined by the number of input pulses to the motor 4. Therefore, the number of pulses corresponding to each of the phases is input to the motor 4 so that the motor 4 is rotated to each of the phases.

  By the way, when the detected temperature of the pan bottom temperature sensor Ba rises to the upper limit temperature of the predetermined set temperature range, the motor 4 is rotated in the forward rotation direction to the minimum heating power phase θ1 n to make the heating power the first heating power Q1 which is the minimum heating power. Temperature regulation control may be performed to increase the thermal power when the temperature detected by the throttling or pan bottom temperature sensor Ba falls to the lower limit temperature of the set temperature range. However, if slippage of the motor 4 occurs due to the pricking member of the interlocking mechanism 5 or the like, the valve element 32 for the flow rate control valve corresponds to the first heating power Q1 even if the motor 4 is rotated to the minimum heating power phase θ1 n The thermal power may be larger than the first thermal power Q1 without being displaced to the axial position. As a result, the pan bottom temperature greatly overshoots from the upper limit temperature of the set temperature range and excessively rises.

  Therefore, in the present embodiment, the detector 8 is provided on the cam body 54 which is one of the components of the interlocking mechanism 5, and the motor 4 is one stage higher than the minimum thermal power determined based on the flow rate characteristic at normal rotation. Position range where detector 8 exists when it rotates in the normal rotation direction from the phase θ2n corresponding to the second thermal power Q2 that is the thermal power, and falls within the rotation range from the predetermined phase θa before the minimum thermal phase θ1n to the minimum thermal phase θ1n The position sensor 9 is provided to detect the displacement of the detector 8 to the detection range, with As a result, when the first thermal power Q1 is obtained, the position sensor 9 outputs a detection signal (a signal indicating that the detector 8 has been displaced to the detection range) to ensure that the first thermal power Q1 is obtained. I have to. When the position sensor 9 does not output a detection signal even if the motor 4 is rotated in the forward rotation direction to the minimum heating power phase θ1 n, it is determined that an abnormality has occurred and the gas supply is stopped.

  More specifically, referring also to FIG. 5, the detector 8 is constituted by a projection having a ridge 81 protruding in the backward direction, which is provided on the outer peripheral surface of the cam 54. Further, the position sensor 9 is configured by a micro switch having a detection lever 91. Then, when the detector 8 is in the detection range, the detection lever 91 is pushed up in the backward direction by the ridge 81 of the detector 8, and the position sensor 9 formed of a micro switch outputs a detection signal consisting of an on signal. It is like that.

  By the way, when the indicated thermal power is changed to one of the decrease side and the increase side last time, it is changed to the other of the decrease side and the increase side this time, and the flow adjustment is performed during the angle rotation of the motor 4 for the hysteresis H. The valve body 32 for the valve is not displaced, and the power does not change. Therefore, in the present embodiment, the indicated thermal power is changed to one of the decrease side and the increase side last time (for example, the second thermal power Q2 is changed to the fourth thermal power Q4 on the increase side). The other is changed (for example, the fourth thermal power Q4 is changed to the third thermal power Q3 on the decrease side), and while the motor 4 is rotating at an angle for the hysteresis H, the thermal power change is suddenly canceled and the commanded thermal power is When the power is returned to the power before the change, the rotation of the motor 4 is stopped at that time. According to this, it is possible to save power by avoiding unnecessary power consumption. In this case, the rotational phase at the time of stopping the rotation of the motor 4 is stored, and when the designated thermal power is changed next, the rotational phase corresponding to the changed thermal power and the rotational phase at the time of rotational discontinuation The motor 4 may be rotated by the difference from the above.

  However, when the indicated thermal power is changed from the first thermal power Q1 to the increase side, the motor 4 rotates in the reverse direction from the minimum thermal power phase θ1n to the phase θ1r corresponding to the first thermal power Q1 determined based on the reverse flow rate characteristics. If the motor 4 is rotating in the reverse direction beyond the predetermined phase θa at the time when the change of the heating power is suddenly canceled and the commanded heating power is returned to the first heating power Q1 during the process, the detector 8 is rotated. The position sensor 9 may not output a detection signal due to displacement out of the detection range. In this case, if the rotation of the motor 4 is stopped at the time of cancellation of the thermal power change, the position sensor 9 does not output the detection signal even if the actual thermal power remains the first thermal power Q1, and it can be guaranteed that it is the first thermal power Q1. It will be gone.

  Therefore, in the present embodiment, the indicated thermal power is changed from the first thermal power Q1 to the increase side, and the motor 4 is from the minimum thermal power phase θ1n to the phase θ1r corresponding to the first thermal power Q1 determined based on the reverse flow rate characteristics. When the change of the thermal power is suddenly canceled and the command thermal power is returned to the first thermal power Q1 while rotating in the reverse direction, the motor 4 is not rotated to the minimum thermal power phase θ1 n without stopping the rotation of the motor 4 It was made to rotate in the forward direction. According to this, even if the detector 8 is displaced out of the detection range at the time of cancellation of the thermal power change and the position sensor 9 does not output the detection signal, the detector 8 is rotated by the rotation of the motor 4 up to the minimum thermal phase θ1 n Can be displaced to the detection range, and the position sensor 9 can output a detection signal to guarantee that it is the first thermal power Q1.

  As mentioned above, although embodiment of this invention was described with reference to drawings, this invention is not limited to this. For example, in the above embodiment, the detector 8 is constituted by a projection provided on the cam body 54 and a micro switch is used as the position sensor 9, but the detector 8 is constituted by a magnet attached to the end face of the pin 55 The position sensor 9 may be configured by a reed switch that responds to the magnet. Moreover, it is also possible to change a thermal power steplessly in the range exceeding 2nd thermal power Q2. Furthermore, although the gas valve apparatus of the said embodiment is provided with the solenoid safety valve 2 in addition to the flow control valve 3, it is also possible to abbreviate | omit the solenoid safety valve 2. FIG. Further, the present invention can be similarly applied to a gas valve device provided with a rotary flow control valve having a disk-like valve body which is rotated by a motor via an interlocking mechanism.

B: Burner, GS: gas supply path, 1: valve casing, 3: flow rate control valve, 32: valve body, 4: motor, 5: interlocking mechanism, 54: cam body (component members of interlocking mechanism provided with detector) , 8 ... detector, 9 ... position sensor.

Claims (2)

A gas valve device interposed in a gas supply path to a burner, wherein a flow control valve having a valve body driven by a motor through a interlocking mechanism is provided in a valve casing, The rotation direction of the motor to move in the decreasing direction is the normal direction, and the rotation direction of the motor to move the valve body in the direction to increase the gas flow is the reverse direction. The motor's rotational phase and gas flow rate when the gas flow rate is reduced by rotating the motor in the forward direction of rotation, with the motor's rotational phase difference as the hysteresis. Control the motor when the indicated thermal power indicated by the operation of the thermal power indicating member is changed to the decrease side based on the forward rotation flow rate characteristic representing the relationship between The rotational phase of the motor is shifted in the reverse direction by the amount corresponding to the engine speed, based on the reverse flow rate characteristic that represents the relationship between the motor's rotational phase and the gas flow rate when the gas flow rate is increased by rotation of the motor in the reverse direction. Control of the motor when the indicated thermal power is changed to the increase side,
Since the indicated thermal power is changed to one of the decrease side and the increase side last time, it is changed to the other of the decrease side and the increase side this time, and the thermal power change is suddenly canceled while the motor rotates by an angle for hysteresis. A gas valve device characterized by stopping the rotation of the motor at that time when the instructed thermal power is returned to the thermal power before the change. The gas valve device according to claim 1, wherein when the designated thermal power is the minimum thermal power, the motor is driven in the forward rotational direction up to a predetermined minimum thermal power phase corresponding to the minimum thermal power determined based on the forward flow rate characteristic. The motor is rotated in the normal rotation direction from the phase corresponding to the thermal power one stage higher than the minimum thermal power determined based on the flow characteristic at normal rotation. Providing a position sensor for detecting the displacement of the detector to the detection range with the position range where the detector is present as the detection range when the rotation range from the predetermined phase before the minimum heating phase to the minimum heating phase is
The power change is sudden while the indicated thermal power is changed from the minimum thermal power to the increase side and the motor is rotating in the reverse direction from the minimum thermal power phase to the phase corresponding to the minimum thermal power determined based on reverse flow rate characteristics. A gas valve device characterized by rotating the motor in the forward rotation direction to the minimum heating power phase without stopping the rotation of the motor when the instructed heating power is returned to the minimum heating power after being canceled.

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