JP5935191B2 - Thermal power control device - Google Patents

Description

  The present invention relates to a thermal power control device including an electromagnetic safety valve.

  As a conventional thermal power control device of this type, one having an electromagnetic safety valve and a thermal power control unit in one housing is known (for example, see Patent Document 1). The electromagnetic safety valve includes an electromagnet inside, and is configured to be able to attract and hold an armature connected to the valve body. The valve body is biased by a spring in the valve closing direction, which is the direction away from the electromagnet. Therefore, the valve body is normally in the closed position, but the valve is opened against the biasing force of this spring by an external force, and the electromagnet coil is energized with the armature pressed against the magnetic pole of the electromagnet. Then, the armature is attracted and held on the electromagnet by the magnetic force generated by the electromagnet. Then, even if the force in the valve opening direction from the outside is released, the valve element is held in an attracted and held state by the electromagnet, that is, in the valve opened state.

  On the other hand, the thermal power control unit is composed of one fixed plate and one rotary plate. The fixing plate has a plurality of through holes on the same circumference. In addition, an elongated hole is formed in the rotating plate along the circumference of the same radius as the through hole of the fixed plate. When the rotating plate is rotated, the overlapping state of the elongated holes and the through holes, that is, the size and number of the through holes overlapping the elongated holes change, and the flow rate of the gas passing through the thermal power control unit changes.

  The operation of forcibly opening the valve body of the electromagnetic safety valve and rotating the rotating plate to increase or decrease the gas flow rate is performed by a single motor. A cam is attached to the rotating shaft of the motor. The cam advances and retracts the rod in a direction perpendicular to the rotating shaft, and the valve body is pushed at the tip of the rod to forcibly open the valve. Moreover, the said rotating plate is attached to the front-end | tip of the rotating shaft of a motor.

  When stopping the passage of gas in this thermal power control device, the energization of the electromagnet of the electromagnetic safety valve is stopped to close the valve body, and the phase of the rotating plate is adjusted so that the slot of the rotating plate is fixed to the fixed plate. Although it does not correspond to the through hole, grease is applied between the fixed plate and the rotating plate, but it cannot be guaranteed that the gas flow is completely blocked. For this reason, the gas cutoff of the thermal power control device depends only on the electromagnetic safety valve.

  However, since the gas shutoff is only one stage of the electromagnetic safety valve, an on-off valve is provided upstream, and the on-off valve is closed to provide two-stage shielding. Even if a failure occurs in any of these, the gas can be surely shut off.

Japanese Patent Laid-Open No. 2002-323218 (FIG. 1)

  In the above conventional thermal power control device, it is necessary to provide an opening / closing valve in addition to the electromagnetic safety valve. However, this switching valve requires a mechanism for driving the valve body, that is, a further motor, solenoid coil, etc. The space which an apparatus and an on-off valve occupy becomes large, and the malfunction that the cost of an on-off valve becomes high arises.

  Therefore, in view of the above problems, the present invention has an object to provide a thermal power control apparatus provided with a further on-off valve in addition to an electromagnetic safety valve by using only the thermal power control apparatus without providing an on-off valve having a separate drive mechanism. To do.

In order to solve the above problems, a thermal power control apparatus according to the present invention includes an electromagnetic safety valve in which a valve body is adsorbed and held by an electromagnet and a thermal power control unit that increases or decreases a flow rate, and the electromagnetic safety valve is configured by one motor. In the thermal power control device that forcibly opens the valve and adjusts the flow rate of the gas passing through the thermal power control unit by increasing or decreasing the opening of the thermal power control unit, a built-in on-off valve in series with the thermal power control unit, The on / off valve is opened and closed by the motor in conjunction with the opening degree of the thermal power control unit and the opening and closing of the electromagnetic safety valve, and the electromagnetic safety valve is forcibly opened by a cam rotated by the motor. After opening the safety valve, when the valve body returns to the valve closing direction from the state where the valve body is attracted by the electromagnet, the cam is moved to a position that does not interfere with the valve body closing, and then the opening / closing valve is opened. Characterized in that it makes.

  An open / close valve is added to the conventional thermal power control device composed of a thermal power control unit and an electromagnetic safety valve, but this open / close valve is opened / closed by a motor originally provided, not by adding a separate motor or solenoid coil. This prevents an increase in the size of the thermal power control device.

By the way, the electromagnetic safety valve forcibly moves the valve body of the electromagnetic safety valve in the valve opening direction so that the valve body is attracted to the electromagnet. If the motor stops for some reason while the valve body is forcibly opened, the valve body of the electromagnetic safety valve that is forcibly opened cannot be closed. Therefore, the electromagnetic safety valve is forcibly opened by the cam rotated by the motor, and after opening the electromagnetic safety valve, when the valve body returns from the state of being attracted to the electromagnet to the valve closing direction, the valve body is after the cam has been moved to a position that does not interfere with the closing and so as to open the on-off valve.

  In addition, if the rotating shaft of the motor is penetrated, it is necessary to provide a seal such as an O-ring to prevent gas leakage at the penetrated portion. However, the rotational torque of the motor increases due to friction with the seal. . Therefore, the thermal power control unit includes a fixing plate in which a plurality of through holes through which gas passes is formed and a through hole through which the gas passes, and is in contact with the fixing plate from the upstream side by the motor. The rotating shaft is rotated, and a sub-rotating shaft separate from the rotating shaft of the motor is provided so as to rotate together with the rotating plate while penetrating the fixed plate. It is desired that the cam is engaged and the on-off valve is opened and closed by the auxiliary cam.

  In this configuration, the rotating shaft of the motor does not pass through the rotating plate, and therefore it is not necessary to provide a seal with respect to the rotating shaft of the motor, the rotational torque of the motor does not increase, and the load on the motor can be reduced. .

  By the way, in the mechanism that closes the valve body by pushing the valve body of the on-off valve with the auxiliary cam, the stroke that moves the valve body in the valve closing direction decreases when the cam surface wears, and the valve body is pressed against the valve opening. Power is reduced. Therefore, the valve body of the on-off valve is biased in the valve closing direction by the biasing force of the spring, and is configured to open by being pulled in the valve opening direction against the biasing force by the auxiliary cam. In this case, even if the surface of the auxiliary cam is worn, the stress for allowing the valve body to be seated on the valve seat does not change, so that safety can be maintained for a long period of time.

  As is apparent from the above description, the present invention adds an opening / closing valve to the conventional thermal power control apparatus, but does not require a new motor, solenoid coil, or the like to open / close the open / close valve. Can be made as small as possible.

Sectional drawing which shows an example of the thermal-power adjustment apparatus by this invention Sectional drawing which shows the characteristic part of the thermal-power adjustment apparatus in 2nd Embodiment. It is a figure which shows the relationship between a cam and a rotating shaft, (a) shows A section, (b) shows B section. The figure which shows the phase relationship of the cam and subcam in 2nd Embodiment

  With reference to FIG. 1, 1 is an example of a thermal power control apparatus according to the present invention. This thermal power control apparatus 1 has a die-cast housing 11, in which gas is introduced into an inside through an inlet 12 formed in the lower part in the figure, and the flow rate is adjusted in a range from zero to the maximum, and the upper part is adjusted. It flows out from the formed outlet 13 to a gas burner outside the figure.

  A unitized electromagnetic safety valve 2 is attached in the vicinity of the inlet 12. The electromagnetic safety valve 2 incorporates an electromagnet, which will be described later, and is configured to hold the valve body 21 in an open state by attracting and holding an armature, which will be described later, attached to the valve body 21 with an electromagnet. When energization of the electromagnet is stopped, the valve element 21 is moved in the valve closing direction by the biasing force of the spring, and returns to the valve closing state shown in FIG.

  When the valve body 21 of the electromagnetic safety valve 2 is opened, even if the armature is energized to the electromagnet in a state of being away from the electromagnet, the armature cannot be attracted by the electromagnetic force. Therefore, it is necessary to excite the electromagnet with the armature pressed against the electromagnet by forcibly opening the valve body 21 with the tip 51a of the rod unit 51. The rod unit 51 moves forward and backward as the cam 5 rotates.

  The cam 5 is rotated by a motor (for example, a stepping motor) 4. A joint 42 is fixed to the rotating shaft 41 of the motor 4, and the cam 5 is configured to rotate by engaging with the joint 42. Above the joint 42, the thermal power adjusting unit 3 is provided.

  The thermal power adjusting unit 3 includes a fixed plate 31 positioned above and a rotating plate 32 that presses against the fixed plate 31 from below. The joint 42 is engaged with the rotating plate 32 so that no hysteresis occurs. Therefore, when the rotating shaft 41 of the motor 4 rotates, the rotating plate 32 rotates with the rotation.

  The fixed plate 31 has a plurality of through holes 31a on the same circumference. The rotating plate 32 is formed with one long hole 32a along the circumference having the same radius as the circumference in which the through holes 31a are formed. Therefore, when the rotating plate 32 rotates and the elongated hole 32a overlaps with any one of the through holes 31a, the gas can flow upwardly over the fixed plate 31 through both of them. Further, the gas does not flow upward of the fixed plate 31 in a state where the long hole 32a does not overlap any of the through holes 31a.

  The auxiliary rotating shaft 6 is fixed to the upper surface of the rotating plate 32. The auxiliary rotating shaft 6 penetrates the fixed plate 31 and protrudes upward, and an auxiliary joint 60 is attached to the upper end of the auxiliary rotating shaft 6. A sub cam 61 is engaged with the sub joint 60.

  The auxiliary rod unit 62 is in contact with the auxiliary cam 61. When the auxiliary cam 61 rotates and the auxiliary rod unit 62 moves to the left in the drawing by the urging force of the spring, the auxiliary rod unit 62 The attached sub-valve body 63 moves to the left side in the figure and opens the valve port 64. When the auxiliary cam 61 is further rotated from this state to return the auxiliary rod unit 62 to the right side, the auxiliary valve body 63 is pressed against the valve port 64 and the valve port 64 is closed.

  As described above, in the configuration shown in FIG. 1, the electromagnetic safety valve 2 that opens and closes the gas passage in the gas passage from the inlet 12 to the outlet 13, the thermal power adjuster 3 that adjusts the flow rate from zero to the maximum, and An auxiliary valve body 63 that opens and closes the gas passage is provided.

  In the configuration shown in FIG. 1, it is the biasing force of the spring that moves the sub-valve body 63 in the valve opening direction, but the movement in the valve closing direction causes the sub-cam 61 to move against the biasing force. This is done by pushing the rod unit 62 in the right direction in the figure. That is, the force that presses the sub valve body 63 against the valve port 64 is determined by the lift amount of the sub cam 61. Therefore, when the surface of the auxiliary cam 61 and the contact surface of the auxiliary rod unit 62 are worn, the lift amount is substantially reduced, and the pressing force of the auxiliary valve body 63 against the valve port 64 is reduced.

  In order to eliminate such a concern, for example, the configuration shown in FIG. 2 can be adopted. In this configuration, the sub-cam 61 is covered with the box-shaped slider 7, and the sub-valve body 63 and the slider 7 are connected via the shaft unit 71. In this configuration, the sub valve body 63 is closed by the biasing force of the spring, so that it is pressed against the valve port 64 with a constant force over time without being affected by the wear of the sub cam 61 or the like. . In the configuration shown in FIG. 2, when the surface of the auxiliary cam 61 is worn, the fully opened position of the auxiliary valve body 63 approaches the valve port 64 by the wear amount. The flow rate when fully opened is not substantially affected.

  The cam 5 is engaged with the rotating shaft 41 via a joint 42. Further, the sub cam 61 is engaged with the sub rotating shaft 6 through the sub joint 60 in the same manner. The reason why the joint 42 and the sub-joint 60 are interposed in this way is to give hysteresis to the rotation of the cam 5 and the sub-cam 61.

  Referring to FIG. 3, as shown in FIG. 3A, when the rotation shaft 41 rotates clockwise in the figure (forward rotation direction), the advance surface 42 a of the joint 42 contacts the front engagement surface 5 a of the cam 5. To rotate the cam 5 clockwise. When the rotary shaft 41 is rotated counterclockwise (reverse rotation direction) from this state, the joint 42 is immediately reversed, but the cam 5 does not rotate until the reverse movement surface 42b comes into contact with the rear engagement surface 5b.

  Similarly, as shown in (b), when the sub rotation shaft 6 rotates clockwise in the figure, the advance surface 60a of the sub joint 60 abuts on the front engagement surface 61a of the sub cam 61 and turns the sub cam 61 clockwise. Rotate. If the sub-rotating shaft 6 is rotated counterclockwise from this state, the sub-joint 60 is immediately reversed, but the sub-cam 61 does not rotate until the reverse movement surface 60b comes into contact with the rear engagement surface 61b.

  Referring to FIG. 4, (a) shows an initial state. In this state, both the valve body 21 and the sub-valve body 63 of the electromagnetic safety valve 2 are in the closed state, and although not shown, the elongated hole 32a of the rotating plate 32 is not in agreement with any through hole 31a of the fixed plate 31. . When the motor 4 is operated from this state and the rotating shaft 41 is rotated forward, the cam 5 pushes the rod unit 51 and the tip 51a of the rod unit 5 forcibly opens the valve element 21, as shown in FIG. Let As a result, the armature 20 a connected to the valve body 21 is pressed against the electromagnet 20. Then, energization of the electromagnet 20 is started, and the armature 20 a is attracted to the electromagnet 20. On the other hand, the auxiliary valve body 63 has not been opened. If a failure occurs in the state shown in (b) and the motor 4 does not operate, the rod unit 51 is obstructed and the valve body 21 cannot be returned to the closed state. Therefore, the closed state of the auxiliary valve body 63 is ensured. Because.

  When the motor 4 is further operated from the state of (b), the cam 5 is retracted from the position where the rod unit 51 is pressed, and when the energization to the electromagnet 20 is stopped, the valve element 21 can be closed, and from that point The valve opening operation of the valve body 63 starts.

  When the motor 4 is further operated from the state of (c), as shown in (d), the sub cam 61 moves the slider 7 to the left in the drawing and pulls the sub valve body 63 to open the sub valve body 63. Let me speak.

  In the state (d), since the valve body 21 and the sub-valve body 63 are opened, the flow rate of the gas is adjusted by rotating the rotating plate 32 forward and backward. In the gas adjustment range, the cam 5 and the sub-cam 61 hardly rotate due to the hysteresis effect described above, and both the valve body 21 and the sub-valve body 63 remain in the open state.

  When the downstream gas burner (not shown) is extinguished, energization of the electromagnet 20 is stopped and the valve body 21 is closed, and the motor 4 is continuously rotated forward so that the state shown in FIG. By returning, the auxiliary valve body 63 is closed.

  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 Electromagnetic safety valve 3 Thermal power control part 4 Motor 5 Cam 5 Rod unit 6 Subrotation shaft 7 Slider 11 Housing 12 Inlet 13 Outlet 21 Valve body 31 Fixed plate 31a Through-hole 32 Rotary plate 32a Long hole 41 Rotary shaft 42 Joint 51 Rod unit 60 Sub joint 61 Sub cam 62 Sub rod unit 63 Sub valve body 63 Valve body 64 Valve port 71 Shaft unit

Claims (4)

An electromagnetic safety valve whose valve body is adsorbed and held by an electromagnet and a thermal power control unit that increases or decreases the flow rate are built in series, and the electromagnetic safety valve is forcibly opened by one motor, and the opening degree of the thermal power control unit is increased. In a thermal power control apparatus that adjusts the flow rate of gas passing through the thermal power control unit by increasing or decreasing the value, a built-in on-off valve is connected in series with the thermal power control unit, and linked to the opening of the thermal power control unit and the opening and closing of the electromagnetic safety valve. The on-off valve is opened and closed by the motor, and the electromagnetic safety valve is forcibly opened by a cam rotated by the motor, and after opening the electromagnetic safety valve, the valve body is adsorbed by an electromagnet. A thermal power control device that opens the on-off valve after the cam has moved to a position that does not interfere with the valve closing when the valve body returns from the closed state . The thermal power control unit is formed by a fixing plate formed with a plurality of through holes through which gas passes and a through hole through which gas passes, and is rotated by the motor in contact with the fixing plate from the upstream side. A sub-rotating shaft separate from the motor rotating shaft is provided so as to rotate with the rotating plate while penetrating the fixed plate, and a sub-cam is provided at the downstream end of the sub-rotating shaft. 2. The thermal power control device according to claim 1, wherein the on / off valve is opened and closed by the auxiliary cam. An electromagnetic safety valve whose valve body is adsorbed and held by an electromagnet and a thermal power control unit that increases or decreases the flow rate are built in series, and the electromagnetic safety valve is forcibly opened by one motor, and the opening degree of the thermal power control unit is increased. In a thermal power control apparatus that adjusts the flow rate of gas passing through the thermal power control unit by increasing or decreasing the value, a built-in on-off valve is connected in series with the thermal power control unit, and linked to the opening of the thermal power control unit and the opening and closing of the electromagnetic safety valve. The on-off valve is opened and closed by the motor, and the heating power control unit is formed with a fixing plate having a plurality of through holes through which gas passes and a through hole through which gas passes. The rotating plate is rotated by the motor while being in contact with the plate from the upstream side. The auxiliary rotating shaft is separated from the rotating shaft of the motor and rotates together with the rotating plate while passing through the fixed plate. So that Vice downstream tip of the rotary shaft sub cam engaged, the auxiliary cam thermal power adjusting device characterized in that so as to open and close the opening and closing valve by the. The valve body of the on-off valve is biased in the valve closing direction by a biasing force of a spring, and is opened by being pulled in the valve opening direction against the biasing force by the auxiliary cam. The thermal power control apparatus of Claim 2 or Claim 3.