JP5334680B2 - Thermal power control device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To eliminate inconvenience of requiring a long distance from a rotary shaft to a solenoid safety valve, to require size enlargement of a fire power regulator as the whole, as a rod is provided to be advanced and retreated along a substantially right-angled direction with respect to the rotary shaft of a motor, in a conventional fire power regulator, and since the solenoid safety valve is required to be arranged along a distal end direction of the rod. <P>SOLUTION: This fire power regulator eliminates the solenoid safety valve, and is provided with an opening and closing mechanism in stead thereof. The opening and closing mechanism is constituted to conduct all of valve opening, hold of the valve opening and valve closure by the motor. An electromagnet is not required although used in the prior art. <P>COPYRIGHT: (C)2011,JPO&amp;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, openings are provided in both a movable plate that is rotated by a motor and a fixed plate that is held in contact with the movable plate. There has been known one provided with a thermal power adjusting unit that adjusts the thermal power by adjusting the amount of gas passing through the overlapping portion of both openings by increasing / decreasing the overlapping area. Further, provided with the electromagnetic safety valve on the upstream side of the thermal power adjusting unit, arranged rod which moves by being pushed by the cam and cam rotated by a motor, the electromagnetic safety valve by moving the Rod rotates and cam Is known to forcibly open the valve.

  This electromagnetic safety valve incorporates an electromagnet for holding the valve body of the electromagnetic safety valve in an open state. When a holding current is applied to the built-in electromagnet while the valve body of the electromagnetic safety valve is forced to the fully open state by the rod, the armature connected to the valve body is attracted to the electromagnet, and the rod Even if the force that has been forcibly opened by returning to the position is released, the valve element is held open by the electromagnetic force of the electromagnet. When the fire is extinguished, the holding current supplied to the electromagnet is cut off, and the valve element is closed by the biasing force of the spring.

JP 2006-189231 A (FIG. 5)

  In the above conventional thermal power control device, a rod must be provided so as to advance and retract in a direction substantially perpendicular to the rotation axis of the motor, and an electromagnetic safety valve must be provided in the tip direction of the rod. This causes a problem that the distance to the heat source increases and the size of the entire thermal power control apparatus increases.

  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 problems, the thermal power control apparatus according to the present invention provides openings in both the movable plate rotated by the motor and the fixed plate held in contact with the movable plate, and moves the movable plate. By adjusting the amount of gas passing through the overlapping part of both openings by adjusting the area of overlap of both openings by adjusting the amount of gas to adjust the thermal power, and provided in series with this thermal power control unit, by the motor A thermal power control apparatus comprising an opening / closing mechanism for opening and closing a gas passage to the thermal power control unit, wherein the opening / closing mechanism includes a valve body biased in a valve closing direction, and the valve body is opened against the biasing force. The above-mentioned motor , the operation of holding the opened valve body against the urging force and keeping the valve open, and the operation of closing the valve body in the opened state while gradually reducing the urging force. It is characterized by being performed by.

  Conventionally, an electromagnetic safety valve is used. However, in the above configuration, the electromagnetic safety valve is eliminated, and an opening / closing mechanism is provided instead. This opening / closing mechanism performs valve opening, valve opening holding, and valve closing by the motor. Therefore, it is not necessary to provide an electromagnet unlike the electromagnetic safety valve used conventionally.

  By the way, in the fire extinguishing state, it is necessary to cut off the supply of gas to the burner, and the gas can be cut off by closing the open / close mechanism. However, when it is desired to improve the reliability more than the single seal with only the opening / closing mechanism, when the opening / closing mechanism is in a valve-closed state, the opening of the movable plate and the opening of the fixed plate do not coincide with each other. What is necessary is just to enable it to form the interruption | blocking state which interrupts | blocks supply of this.

  As is clear from the above description, the present invention does not require the use of an electromagnetic safety valve, so the size of the thermal power control device can be made smaller than the conventional one.

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. Since the opening 31 and the opening 41 do not overlap as shown in the figure, the gas is blocked by the valve body 51, the movable plate 3, and the fixed plate 4, and does not flow to the cam member 23 side.

  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). At this time, the valve body 51 and the two mechanisms of the movable plate 3 and the fixed plate 4 are in a closed state, so that a so-called double seal is formed and the gas supply to the burner can be reliably shut off. 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). In this state, the single seal by the valve body 51 is performed, but the motor 2 is reversely rotated by the fire extinguishing operation for the subsequent point extinguishing operator to return to the double seal state shown in FIG.

  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 since it is not necessary to use the said valve shaft 5 in the structure shown in this FIG. 6, the thermal power control 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 adjusting device 2 Stepping motor 3 Movable plate 4 Fixed plate 5 Valve shaft 7 Movable plate 11 Stopper 22 Phase detection sensor 24 Cam part 51 Valve body 72 Valve opening part 73 Valve closing part

Claims (2)

Openings are provided in both the movable plate rotated by the motor and the fixed plate held in contact with the movable plate, and the overlapping area of both openings is increased or decreased by moving the movable plate. A thermal power control unit that adjusts the thermal power by adjusting the amount of gas that passes through the overlapping portion, and an opening and closing mechanism that is provided in series with the thermal power control unit and opens and closes a gas passage to the thermal power control unit by a motor. In the thermal power control apparatus, the open / close mechanism includes a valve body biased in the valve closing direction, and opens the valve body against the biasing force, and the opened valve body resists the biasing force. Then, the operation for maintaining the valve open state and the operation for closing the valve body in the valve open state while gradually reducing the urging force are all performed by the motor.   When the opening / closing mechanism is in a valve-closed state, the opening of the movable plate and the opening of the fixed plate do not coincide with each other, so that a shut-off state that shuts off the gas supply to the burner can be formed. The thermal power control apparatus according to claim 1.

Images