JP2010266151A - Fire power regulating device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To surely leave a burner in a state that a gas is not supplied thereto in a case when a phase detection sensor 22 is failed, or a microcomputer controlling an operation of a stepping motor goes out of control, in a fire power regulating device provided with the phase detection sensor for detecting a phase of a rotating shaft. <P>SOLUTION: In this fire power regulating device for regulating a gas flow rate to the burner by increasing and decreasing an overlapping area of an opening 31 of a rotating plate 3 and an opening 41 of a fixed plate 4 by rotating a movable plate 3 by the stepping motor 2, a cam member 23 rotated by the rotating shaft 21 is provided with an engagement section 23a, a stopper 11 is disposed at a device body side, and the rotation of the rotating shaft 21 is forcibly stopped by bringing the engagement section 23a into contact with the stopper. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to a thermal power adjusting device that is incorporated in a gas stove or the like and adjusts the thermal power of a burner by a motor.

  As a conventional thermal power control device of this type, a rectangular fixing plate is provided, and a plurality of openings are provided in the fixing plate along the longitudinal direction, and sliding in a state of surface contact with the fixing plate. A thing provided with a movable plate is known. The movable plate is provided with one opening and is configured to slide back and forth by a motor.

  Since such a configuration is employed, when the movable plate is slid by operating the motor, the overlapping area of the opening formed in the movable plate and the plurality of openings formed in the fixed plate changes. Since the overlapping part of both openings will penetrate, if the gas is allowed to pass through the overlapping part, the gas passage area is increased or decreased by sliding the movable plate, and thereby the gas supplied to the burner. The amount can be adjusted.

  The movable plate is moved backward so that the opening of the movable plate does not overlap any of the openings of the fixed plate, so that the gas supply to the burner is stopped, and then the burner is ignited. Until then, the gas supply to the burner is closed.

Japanese Patent No. 4139707 (FIG. 4)

  In the conventional thermal power control apparatus, in order to slide the movable plate, it is necessary to apply a reciprocating force to the movable plate. When extinguishing a fire, the movable plate must be pulled back. For example, in the case of an emergency in which the movable plate needs to be extinguished urgently from the forward end position, that is, a strong fire state, the movable plate must be pulled back a long distance. Therefore, there is a problem that it takes a relatively long time until the burner is actually extinguished even though it is desired to extinguish it urgently.

  Then, this invention makes it a subject to provide the thermal-power adjustment apparatus which does not produce the above-mentioned malfunction in view of said problem.

  In order to solve the above-described problem, the thermal power control apparatus according to the present invention provides openings in both a movable plate that is moved by a motor and a fixed plate that is held in contact with the movable plate, and moves the movable plate. In the thermal power control device having a thermal power control unit that adjusts the thermal power by adjusting the amount of gas passing through the overlapping part of both apertures by increasing / decreasing the overlapping area of both apertures and rotating the movable plate by a motor An opening / closing mechanism is provided which is connected in series to the thermal power control unit and opens and closes the gas passage by the motor.

  In the conventional thermal power control device, the movable plate is slid, and in the fire extinguishing state, the gas flow is cut off at the mating surface between the movable plate and the fixed plate. However, the sealing performance tends to deteriorate due to wear or the like. In contrast, in the present invention, since a separate opening / closing mechanism is provided, even if wear occurs between the movable plate and the fixed plate, the gas is surely shut off.

  In addition, when the motor is rotated forward to increase the thermal power, it is sufficient to reverse the motor during normal fire extinguishing and further reverse the motor from the low fire position.For example, when the fire is urgently extinguished in a high fire state If the motor is further rotated forward from a strong fire state, the opening / closing mechanism is closed and the gas supply to the burner can be stopped.

  This can be realized by rotating the movable plate instead of sliding as in the conventional case. However, when the movable plate is rotated, if the phase cannot be detected, there is a problem such as the movable plate continues to rotate.

  Therefore, the opening / closing mechanism opens and closes the gas passage with a cam rotated by the motor, and is provided with a phase detection sensor for detecting the rotational phase of the movable plate, and the phase detection by the phase detection sensor is impossible. A stop means for stopping the rotation of the movable plate may be provided at a position where the opening / closing mechanism is closed without using the detection signal of the phase detection sensor in the event of an abnormality. Thereby, the open / close mechanism can be closed without using the detection signal of the phase detection sensor.

  The stop means may be constituted by a stopper portion provided on the apparatus main body side and an engaging portion that rotates together with the rotation shaft of the motor and contacts the stopper portion at a position where the closing mechanism is in a closed state.

  Alternatively, the stopping means may be configured to have a cam that rotates together with the rotating shaft of the motor and a limit switch that is attached so that the on / off state is reversed by the cam at a position where the closing mechanism is in the closed state. Good.

  In case of emergency fire extinguishing due to extinction or the like, if the thermal power is smaller than the strong fire, the motor is reversed to close the opening / closing mechanism, and if the thermal power is strong fire, the motor is rotated forward to close the opening / closing mechanism. The gas supply to the burner can be stopped immediately.

  As is clear from the above description, the present invention is provided with an opening / closing mechanism separately from the thermal power control unit, so that the thermal power control unit is not provided with a closing function or the thermal power control unit has a deteriorated closing function. Even if it exists, gas can be reliably interrupted | blocked by the opening / closing mechanism. In addition, when a fire is lost due to a cold or a spill, gas must be immediately extinguished to prevent leakage of gas from the burner. When the fire is extinguished, the opening / closing mechanism can be closed in a short time by rotating the motor forward or backward. Furthermore, even if the phase of the motor cannot be detected due to a failure or the like, the rotation is stopped at a position where the opening / closing mechanism is closed by the stop means, so that the gas supply to the burner can be stopped reliably.

The figure which shows the structure of one embodiment of this invention Diagram showing relationship between cam phase and gas passage area Diagram showing cam profile Diagram showing the structure of the phase detection sensor The figure which shows other embodiment. Furthermore, the figure which shows 3rd Embodiment Diagram showing the configuration of the movable plate The figure which shows the opening and closing state of the gas passage by the movable plate

  Referring to FIG. 1, reference numeral 1 denotes a thermal power control apparatus according to the present invention. A stepping motor 2 is attached to the lower part of the thermal power control apparatus 1. A phase detection sensor 22 for detecting the rotational phase of the rotary shaft 21 is attached to the rotary shaft 21 of the stepping motor 2. A cam member 23 is further attached to the rotating shaft 21 so as to rotate together with the rotating shaft 21. A cam portion 24 is provided on the outer periphery of the cam member 23. When the stepping motor 2 is operated to rotate the rotating shaft 21, the cam portion 24 pushes the valve shaft 5 to the right in the drawing. A valve body 51 as an opening / closing mechanism is attached to the valve shaft 5, and when the valve shaft 5 is pushed rightward, the valve body 51 is changed from the closed state to the opened state. When the valve body 51 is opened, the gas passes around the valve body 51 and flows toward the cam member 23.

  A circular movable plate 3 is engaged with the upper portion of the cam member 23, and the movable plate 3 is configured to rotate in conjunction with the cam member 23. The movable plate 3 is pressed against the lower surface of the fixed plate 4. The movable plate 3 has one opening 31, and the fixed plate 4 has five openings 41 in the present embodiment.

  When the opening 31 of the movable plate 3 overlaps any one of the openings 41 due to the phase of the movable plate 3, the gas flows further downstream through the overlapped portion and is supplied to the burner. When the movable plate 3 rotates in the forward direction, the area where the opening 31 and the opening 41 overlap is increased. And when this overlapping area increases, the amount of gas supplied to the burner increases and the thermal power increases.

  By the way, the movable plate 3 and the cam member 23 are rotated in the forward direction and the reverse direction within a predetermined angle range. That is, when the movable plate 3 and the cam member 23 are rotated in the forward direction and the valve body 51 is rotated from the closed state to a position where the maximum opening is exceeded and the valve is closed again, it is necessary to further rotate in the forward direction. Absent. However, a stopping means is provided so that the movable plate 3 and the cam member 23 do not rotate beyond the angular range due to some abnormality. Specifically, the stopper 11 is provided on the apparatus main body side, and an engaging portion 23a that contacts the stopper 11 is formed in the cam member 23 when the cam member 23 exceeds a predetermined angle range. Accordingly, if the stepping motor 2 continues to rotate in either the forward or reverse direction, the engaging portion 23a comes into contact with the stopper 11 and the rotation of the rotating shaft 21 is forcibly prevented so that the cam member 23 does not rotate any further. Stop.

  Referring to FIG. 2, in the above configuration, in the state shown in FIG. 2A, the cam portion 24 is not in contact with the valve shaft 5, that is, the valve body 51 is in a closed state. Therefore, even if the opening 31 overlaps with a part of the openings 41 as shown in the drawing, the gas is blocked by the valve body 51 and does not flow to the cam member 23 side. In this state, the opening 31 may be set so as not to overlap any of the openings 41 when the valve body 51 is in a closed state.

  In the figure, when the cam member 23 is rotated in the right direction (forward direction) by the stepping motor 2, the cam portion 24 pushes the valve shaft 5 to the right side and moves it, thereby opening the valve body 51 (FIG. 2B). )). However, the opening degree of the valve body 51 is small in this state. Further, since the opening 31 overlaps only with the two openings 41, the flow rate of the gas supplied to the burner is small. In other words, the burner's firepower is low.

  When the cam member 23 is further rotated in the right direction from the state shown in (b), the valve shaft 5 is moved to the right, and the opening degree of the valve body 51 is increased. Moreover, since the opening 41 which overlaps with the opening 31 increases and the diameter of the overlapping opening 41 increases, the amount of gas supplied to the burner increases. The state shown in (c) is the maximum flow rate, that is, a high fire state. In addition, in normal thermal power control, when the fire is extinguished from the strong fire state shown in (c), the rotating shaft 21 is reversed to return to the state shown in (a) through the state shown in (b). That is, the normal heating power adjustment range is the range shown in (a) to (c). However, for example, in the state shown in (c), if the burner extinguishes fire due to wind or spillage, it is necessary to immediately stop the ejection of gas from the burner. In such a case, the valve body 51 is closed by rotating the rotating shaft 21 forward from the state shown in (c) instead of rotating in the forward direction to the state shown in (d).

  Here, the profile of the cam part 24 is demonstrated with reference to FIG. The profile of the cam portion 24 shown in FIG. 2 is indicated by P1, and when the valve body 51 is gradually opened from the fully closed state and the heating power becomes 3 (medium fire), the opening degree of the valve body 51 is maximum. After that, the valve body 51 was set to be held at the maximum opening until the heating power 5 (high fire). In addition, as shown to P2, you may set to the profile which increases the opening degree of the valve body 51 with the increase in a thermal power until it becomes a thermal power 5 (strong fire). In any case, the profiles P1 and P2 are both gentler than the profile S in which the valve element 51 is fully opened at a stretch in the state of thermal power 1 (low heat).

  When the valve body 51 is suddenly opened to the fully open state as in the profile S, a stepping motor 2 having a high torque must be used, the stepping motor 2 becomes large, power consumption increases, and the stepping motor 2 The price of will be higher. On the other hand, when the heating power is small, the opening degree of the valve body 51 does not need to be fully opened. Therefore, the profiles P1 and P2 are more advantageous because the small stepping motor 2 can be used.

  The phase detection sensor 22 is a semi-fixed resistance type. As shown in FIG. 4, a C-shaped carbon film 22 b and an annular conductive portion 2 a are provided inside the phase detection sensor 22, and a slider 22 c that rotates together with the rotating shaft 21 is incorporated. Yes. When the slider 22c rotates, the short-circuit portion between the resistance coating 22b and the conductive portion 22a moves, so that the electric resistance continuously changes and the phase can be detected from the output partial pressure. In addition, a discontinuous non-detection range is always formed in the resistance coating 22b. Therefore, this non-detection range is set to a position where the cam member 23 does not normally rotate, that is, a position where the valve shaft 5 is detached from the cam portion 24 and the valve body 51 is closed. This position also coincides with the set position of the stopper 11.

  As described above, the rotational phase of the rotary shaft 21 is always detected by the phase detection sensor 22. Then, the rotation of the stepping motor 2 is controlled based on the detected phase data. Further, for example, when the burner is extinguished urgently during ignition or when a misfire occurs during ignition as described above, the stepping motor 2 is reversed, the opening 31 is moved to the low-fire side, and the valve body 51 is closed. It is determined from the phase signal output by the phase detection sensor 22 whether the valve is faster or it is faster to rotate forward and move the opening 31 to the high fire side to close the valve body 51.

  As described above, since the phase control of the stepping motor 2 is always performed based on the phase signal of the phase detection sensor 22, if the phase signal is not output due to disconnection or the like, the phase of the rotary shaft 21 of the stepping motor 2 is changed. It cannot be detected. In such a case, when the stepping motor 2 is rotated until the above-described engaging portion 23a comes into contact with the stopper 11, the rotation of the rotating shaft 21 causes gas to be supplied to the burner while the valve body 51 is closed. In such a state, the stopper 11 is forcibly stopped. The emergency rotation direction may be either forward or reverse.

  For example, as shown in FIG. 5, the cam 61 is further attached to the rotating shaft 21, and the limit switch 6 is provided so that the valve body 51 is turned on at the closed position as shown in FIG. Can be adopted. In this configuration, even if a disconnection failure occurs in the phase detection sensor 22, the operation of the stepping motor 2 may be stopped at a position where the limit switch 6 is turned on. However, when a microcomputer (not shown) that controls the operation of the stepping motor 2 runs away, a configuration in which the rotation of the rotary shaft 21 is mechanically stopped using the stopper 11 is effective.

  By the way, in the above configuration, since the valve body 51 is provided on the valve shaft 5, the size of the entire apparatus can be reduced as compared with the conventional device in which an electromagnetic safety valve is further provided at the tip of the valve shaft 5, but for further downsizing. Alternatively, the configuration shown in FIG. 6 may be adopted.

  In this figure, 6 is a joint member corresponding to the cam member. However, the joint member 6 is not formed with a cam portion, and is merely for connecting the rotary shaft 21 to the movable plate 7. The movable plate 7 is formed in a cylindrical shape whose upper portion is closed, and an opening 71 corresponding to the opening 31 is provided on the upper surface. A valve opening portion 72 and a valve closing portion 73 constituting an opening / closing mechanism are formed on the peripheral surface of the cylinder portion.

  When the movable plate 7 is incorporated, the valve opening portion 72 and the valve closing portion 73 are alternatively aligned with the gas passage 12 by the phase of the movable plate 7.

  That is, as shown in FIG. 8, in the state shown in FIG. 8A, the valve closing portion 73 is coincident with the gas passage 12, so that the gas cannot flow further downstream from the gas passage 12. When the movable plate 7 is rotated and the valve opening 72 coincides with the gas passage 12, the gas is supplied from the gas passage 12 through the opening 71 and the opening 41 to the burner. And in the structure shown in this FIG. 6, since it is not necessary to use the rod valve axis | shaft 5, the thermal-power adjustment apparatus 1 can be further reduced in size.

  In addition, this invention is not limited to an above-described form, You may add a various change in the range which does not deviate from the summary of this invention.

DESCRIPTION OF SYMBOLS 1 Thermal power control apparatus 2 Stepping motor 3 Movable plate 4 Fixed plate 5 Valve shaft 11 Stopper 22 Phase detection sensor 24 Cam part 51 Valve body

Claims (5)

  An opening is provided in both the movable plate that is moved by the motor and the fixed plate that is held in contact with the movable plate. By moving the movable plate, the overlapping area of both openings is increased or decreased. In a thermal power control apparatus having a thermal power control unit that adjusts the thermal power by adjusting the amount of gas passing through the overlapping portion, the movable plate is rotated by a motor and connected in series to the thermal power control unit. A thermal power control apparatus comprising an opening / closing mechanism for opening / closing a passage.     The opening / closing mechanism opens and closes the gas passage with a cam rotated by the motor, and is provided with a phase detection sensor for detecting the rotational phase of the movable plate, and the phase detection by the phase detection sensor becomes impossible. 2. The thermal power control apparatus according to claim 1, further comprising stop means for stopping the rotation of the movable plate at a position where the opening / closing mechanism is in a closed state without using a detection signal of the phase detection sensor in the event of an abnormality.   The stop means includes a stopper portion provided on the apparatus main body side, and an engagement portion that rotates together with the rotation shaft of the motor and contacts the stopper portion at a position where the closing mechanism is in a closed state. The thermal power control apparatus according to claim 2.   The stop means includes a cam that rotates together with a rotating shaft of a motor, and a limit switch that is mounted so that the on / off state is reversed by the cam at a position where the closing mechanism is in a closed state. The thermal power control apparatus as described in.   In an emergency fire extinguishment due to extinction or the like, the opening and closing mechanism is closed by reversing the motor in a state where the heating power is less than a strong fire, and the opening and closing mechanism is closed by rotating the motor forward in a state where the heating power is strong. The thermal power control apparatus in any one of Claim 1 to 4.

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