JP2010007746A - Valve element drive device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a valve element drive device having a simple construction and capable of driving an output member in predetermined conditions. <P>SOLUTION: In the valve element drive device 1 of an electric type automatic toilet flushing device, a stopper 80 utilizing contact of members is provided for the purpose of regulating a position of the output member 20 in an open direction and the position of the output member 20 in the open direction is regulated by the stopper 80. A motor drive circuit 6, in a first drive mode, supplies first drive voltage to a direct current motor 5 and moves the valve element from a close state to an open state and then in a second drive mode, supplies second drive voltage lower than the first drive voltage to the direct current motor 5, further moves the valve element to the open state and keep applying the second drive voltage to the direct current motor 5 even after the stopper 80 operates. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a valve body driving device for driving a valve body for opening and closing a drain hole of a water storage tank installed in a flush toilet or the like.

  Electric flush toilets are becoming popular in flush toilets. In such electric flush toilets, a valve body for opening and closing a drain hole of a water tank is driven by a switch operation. When performing such an opening / closing operation, after starting the driving of the output member, in the driving force transmission mechanism from the driving source to the output member, the meshing of the gears is disengaged, thereby closing the drain hole after a predetermined time. . In addition, after starting to drive the output member, a mechanical timer switch is configured by utilizing the rotation of the gear, and the power supply to the drive source is stopped by the timer switch. Patent Literatures 1 to 3).

Further, if a mechanical timer switch using the rotation of the gear is configured, the drive source can be controlled in conjunction with the operation of the output member accurately, and the torque for the output member can be switched (Patent Documents 1 to 3). reference).
JP 2002-39318 A JP 2002-256611 A Japanese Patent Laid-Open No. 11-200453

  However, after the drive of the output member is started, in the driving force transmission mechanism from the drive source to the output member, if the configuration is adopted in which the drainage hole is closed after a predetermined time by disengaging the gears, recombination There is a problem that a collision sound is generated at the time, and the tooth tips are not properly meshed with each other and become locked.

  In addition, when a timer switch is built in the driving force transmission mechanism, there is a problem in that the cost increases because the incorporation of members and the routing of lead wires become complicated.

  In view of the above problems, an object of the present invention is to provide a valve body drive device that can drive an output member under a predetermined condition with a simple configuration.

  In order to solve the above problems, in the present invention, a valve body drive having an output member coupled to a valve body for opening and closing a drain hole of a water storage tank, and a drive mechanism for driving the output member in an opening direction. In the apparatus, the drive mechanism supplies a drive voltage to the DC motor, a DC motor as a drive source for driving the output member, a driving force transmission mechanism that transmits the output of the DC motor to the output member, and A motor drive circuit; and a stopper that defines a position in the opening direction of the output member by contact between the members, and the motor drive circuit is configured to perform a first operation when the valve body transitions from the closed state to the open state. A first drive mode for supplying drive voltage to the DC motor, and a second drive voltage that is lower than the first drive voltage after the valve body has shifted to the open state, and after the stopper is activated The second wheel drive Second driving mode and, after a predetermined time for applying the voltage to the DC motor, and executes a driving stop operation of stopping the voltage supply to the DC motor.

  In the present invention, for the purpose of defining the position of the output member in the opening direction, a stopper using contact between the members is provided, and the position of the output member in the opening direction is defined by the stopper. In the first drive mode, the motor drive circuit supplies the first drive voltage to the DC motor to shift the valve body from the closed state to the open state, and then in the second drive mode, the valve body is opened. Then, after the stopper is activated, a second drive voltage lower than the first drive voltage is applied to the DC motor. Here, the torque of the DC motor is controlled by the drive voltage. For this reason, when the stopper is operated, the output member is driven with a low torque, so that when the stopper is operated, a loud collision noise is not generated and the member is not damaged. Further, since the first drive mode and the second drive mode are realized by the motor drive circuit, it is not necessary to provide a timer switch in the drive force transmission mechanism. Furthermore, in the second drive mode, the second drive voltage lower than the first drive voltage is supplied to the DC motor, so that the heat generation of the DC motor can be kept low. Here, since the drive voltage is applied even in the second drive mode, even if a deviation occurs between the position of the valve body and the timing when the first drive mode is switched to the second drive mode, the operation of the valve body is hindered. Absent. Therefore, switching control from the first drive mode to the second drive mode may be performed only by control from the motor drive circuit side, and there is no need to provide a timer switch on the drive mechanism side. Therefore, it is possible to simplify the incorporation of members and the lead wires. Furthermore, in the case of a DC motor, there is an advantage that there is less risk of electric shock compared to an AC motor.

  In the present invention, the valve body closes the drainage hole in a state of receiving fluid pressure in the water storage tank. In the case of such a configuration, a large torque is required to shift the valve body from the closed state to the open state. In the present invention, at such timing, the first drive mode applies a high first drive voltage. Therefore, the valve body can be smoothly shifted from the closed state to the open state. Also,. After the valve body has shifted to the open state, a relatively small torque is sufficient. However, in the present invention, at this timing, the second drive mode applies a low second drive voltage. Therefore, low power consumption can be achieved.

  In the present invention, in the driving force transmission mechanism, it is preferable that the driving force is transmitted from the DC motor to the output member only by the tooth wheel train. That is, in the present invention, since it is not necessary to include a sliding portion in the driving force transmission mechanism, there is no problem caused by wear at the sliding portion.

  In the present invention, it is preferable that the drive force transmission mechanism has a constant gear ratio at all times. In other words, the present invention does not use an expensive deformed gear or the like for switching the gear ratio on the way, so that the cost can be reduced.

  In the present invention, it is preferable that the motor drive circuit includes a voltage dividing resistor for generating the first drive voltage and the second drive voltage from a constant voltage. With this configuration, even when two voltages (first drive voltage and second drive voltage) are generated, only one power source is required. Therefore, the circuit configuration can be simplified, and the cost can be reduced.

  In the present invention, it is preferable that a temperature sensor sensitive to the temperature of the DC motor is provided, and the motor driving circuit changes the driving voltage based on a detection result of the temperature sensor. In the present invention, the DC motor may generate heat as long as the voltage (second drive voltage) is applied even during the period in which the stopper is operating after the valve body has shifted to the open state. Monitoring is performed by a sensor, and when the DC motor generates heat, the drive voltage is reduced or the supply of the drive voltage is stopped. Therefore, damage to the DC motor can be prevented.

  In the present invention, it is preferable that the drive mechanism includes a return spring that displaces the output member in a closing direction when supply of a drive voltage from the motor drive circuit to the DC motor is stopped. If comprised in this way, an output member can be displaced movably in a closing direction in both the time of normal operation and a power failure. In addition, since the return spring urges the output member in the closing direction, the return spring also has an effect of preventing a large collision sound from being generated when the stopper is operated.

  In the present invention, for the purpose of defining the position of the output member in the opening direction, a stopper using contact between the members is provided, and the position of the output member in the opening direction is defined by the stopper. In the first drive mode, the motor drive circuit supplies the first drive voltage to the DC motor to shift the valve body from the closed state to the open state, and then in the second drive mode, the valve body is opened. Then, after the stopper is activated, a second drive voltage lower than the first drive voltage is applied to the DC motor. For this reason, when the stopper is operated, the output member is driven with a low torque, so that when the stopper is operated, a loud collision noise is not generated and the member is not damaged. Further, since the first drive mode and the second drive mode are realized by the motor drive circuit, it is not necessary to provide a timer switch in the drive force transmission mechanism. Furthermore, in the second drive mode, the second drive voltage lower than the first drive voltage is supplied to the DC motor, so that the heat generation of the DC motor can be kept low. Here, since the drive voltage is applied even in the second drive mode, even if a deviation occurs between the position of the valve body and the timing when the first drive mode is switched to the second drive mode, the operation of the valve body is hindered. Absent. Therefore, switching control from the first drive mode to the second drive mode may be performed only by control from the motor drive circuit side, and there is no need to provide a timer switch on the drive mechanism side. Therefore, it is possible to simplify the incorporation of members and the lead wires. Furthermore, in the case of a DC motor, there is an advantage that there is less risk of electric shock compared to an AC motor.

  The best mode for carrying out the present invention will be described below with reference to the drawings.

  FIG. 1 is a longitudinal sectional view of a valve body drive device to which the present invention is applied. 2A and 2B are respectively an explanatory diagram showing a planar layout of a drive mechanism configured in the valve body drive device shown in FIG. 1, and an explanatory diagram of a motor drive circuit used in the drive mechanism. .

  A valve body driving device 1 shown in FIG. 1 is an apparatus for driving a valve body (not shown) for opening and closing a drain hole of a water storage tank in an electric automatic toilet cleaning device used for a flush toilet. The first stage of moving the valve body from the closed position of the drain hole to the open position, the second stage of holding the valve body in the open position and draining, and the first stage of moving the valve body from the open position to stop draining The three stages are carried out in order.

  In order to perform such an operation, the valve body driving device 1 has a shaft-like output member 20 in the case 7, and one end of the output member 20 is a valve body via an opening / closing member (not shown). It is connected to. A manual lever shaft 28 is coupled to the other end of the output member 20, and a lever 280 for manually operating the opening / closing member is coupled to the manual lever shaft 28. Therefore, when the manual lever shaft 28 is manually rotated clockwise CW, the output member 20 is rotated clockwise CW and a large amount of flush water can be poured while the manual lever shaft 28 is manually rotated. When rotated clockwise CCW, the output member 20 rotates counterclockwise CCW, and a small amount of washing water for urine can flow.

  The case 7 includes a case main body 71 located on one end side of the output member 20 and a case lid 72 located on the other side of the output member 20, and is formed in a cylindrical shape formed on the case main body 71 and the case lid 72. Bearings 76 and 77 that rotatably support the output member 20 are configured using the cylindrical portions 761 and 771. The case 7 is disposed at a predetermined position with respect to the water tank of the electric automatic toilet cleaning device, and as a result, the output member 20 is disposed at a predetermined position with respect to the valve body. A compression spring 25 is disposed between the case lid 72 and the output member 20, and the output member 20 is biased toward the other end side.

  The drive mechanism 2 described below is configured for the output member 20 configured as described above. In this embodiment, the drive mechanism 2 includes a DC motor 5 as a drive source for driving the output member 20, and a drive force transmission mechanism 3 that transmits the output of the DC motor 5 to the output member 20. For the motor 5, a motor drive circuit 6 described later with reference to FIGS. 3 and 4 is configured. Here, the DC motor 5 can rotate in both directions, and is mounted on the circuit board 62 together with the resistor 627 used in the motor driving circuit 6. A harness 69 is connected to the circuit board 62, and a drive voltage is supplied through the harness 69.

  The driving force transmission mechanism 3 includes a reduction gear train including a pinion 50 fixed to the output member 20 of the DC motor 5, a first gear body 51, a second gear body 52, a third gear body 53, and a fourth gear body 54. The fourth gear body 54 rotates integrally with the output member 20. Among these gears, the fourth gear is fixed to the output member 20 and rotates integrally with the output member 20. The first gear body 51, the second gear body 52, and the third gear body 53 are each rotatably supported on a support shaft fixed to the case 7, and the large-diameter gear portion of the first gear body 51 is a pinion 50. The large gear portion of the second gear body 52 meshes with the small diameter gear portion of the first gear body 51, and the large gear portion of the third gear body 53 meshes with the small diameter gear portion of the second gear body 52. The fourth gear body 54 meshes with the small-diameter gear portion of the third gear body 53.

  Here, when the manual lever shaft 28 is pulled outward in the axial direction, the mechanical connection between the output member 20 and the fourth gear body 54, or the mechanical connection between the fourth gear body 54 and the third gear body 53. When the manual lever shaft 28 is released, the mechanical connection between the output member 20 and the fourth gear body 54 or the mechanical connection between the fourth gear body 54 and the third gear body 53 is restored. If configured to do so, the force required to manually operate the manual lever shaft 28 can be reduced.

  A return spring 30 made of a torsion coil spring is mounted in a deformable state around one end side of the output member 20, and the return spring 30 places the output member 20 that can rotate in both directions in a neutral position. It functions as a spring member that is urged from both sides toward. Here, the return spring 30 is bent at the outer ends in the radial direction to form supported portions 30a and 30b, while the portion sandwiched between the supported portions 30a and 30b is erected from the case body 71. The fixed side protrusion 711 and the movable side protrusion 541 formed on the fourth gear body 54 are located. Further, in the case main body 71, a contact portion 715 that forms the movable side protrusion 541 and the stopper 80 is formed on the side opposite to the side where the fixed side protrusion 711 is located with the fourth gear body 54 interposed therebetween. In this embodiment, when the output member 20 rotates clockwise CCW, a large amount of water is set to flow for stool, and when the output member 20 rotates counterclockwise CCW, a small amount of water flows for urine. Is set. For this reason, the contact portion is formed at a position slightly shifted clockwise CW, on the opposite side of the side where the fixed-side protrusion 711 is located across the fourth gear body 54.

  In this embodiment, when the fourth gear body 54 rotates in the clockwise direction CW, the supported portion 30b is moved in the clockwise direction CW by the movable-side protrusion 541 while the position of the supported portion 30b is fixed by the fixed-side protrusion 711. . Then, when the movable protrusion 541 comes into contact with the contact portion formed on the case main body 71, the rotation stops. After that, when the force applied to the fourth gear body 54 disappears, the return spring 30 returns the force. The fourth gear body 54 rotates counterclockwise CCW and returns to the original position.

  When the fourth gear body 54 rotates counterclockwise CCW, the supported portion 30b is moved counterclockwise CCW by the movable-side protrusion 541 while the position of the supported portion 30a is fixed by the fixed-side protrusion 711. . Then, when the movable protrusion 541 comes into contact with the contact portion formed on the case main body 71, the rotation stops. After that, when the force applied to the fourth gear body 54 disappears, the return spring 30 returns the force. The fourth gear body 54 rotates clockwise CW and returns to the original position.

(Configuration of motor drive circuit)
3 and 4 are a circuit diagram of the motor drive circuit 6 configured in the valve body drive device 1 shown in FIG. 1 and a waveform diagram of the drive voltage output from the motor drive circuit 6, respectively. In this embodiment, as the drive voltage for the DC motor 5, the first drive voltage and the second drive voltage lower than the first drive voltage are used. The voltage is not limited, but in the following description, the case where the first drive voltage is set to 12V and the second drive voltage is set to 5V is exemplified.

  In FIG. 3, the motor drive circuit 6 for the DC motor 5 in the valve body drive device 1 of the present embodiment connects a power supply unit 61 having a power supply 611 that generates a DC voltage of 12 V, and the power supply unit 61 and the DC motor 5. And a first wiring 66 for connecting the power supply unit 61 and the DC motor 5 to each other. A first switch SW 1 is inserted in the first wiring 66. The second wiring 67 is electrically connected to the first wiring 66 in parallel with the first switch SW1, and the second switch SW2 and the resistor 627 are connected in series to the second wiring 67. It is inserted. As the resistor 627, one having a rating of 1 W or more is used.

  Here, both the first switch SW1 and the second switch SW2 perform an opening / closing operation under the control of the control unit 64 having a built-in timer. The control unit 64 controls the first switch SW1 and the second switch SW2 based on an operation on a button switch (not shown) formed on the control panel on the electric automatic toilet cleaning device main body side. In the motor drive circuit 6, the first wiring 66, the second wiring 67 and the resistor 627 are disposed on the circuit board 62 in the case 2, and the power supply unit 61 and the control unit 64 are provided in the electric automatic toilet cleaning device main body. It is arranged in the control panel on the side.

  In the motor drive circuit 6 configured as described above, the control unit 64 performs the first operation as shown in FIG. 4 until an operation is performed on the button switch of the control panel on the electric automatic toilet cleaning device main body side. When the switch SW1 and the second switch SW2 are turned off, and the operation is performed to flow the washing water to the button switch of the control panel at time T0, the control unit 64 performs the operation from time T0 to time T1. During the period, the first switch SW1 and the second switch SW2 are turned on. As a result, as shown in FIG. 4, the voltages A, B, and C at the positions shown in FIG. 3 are 5V, 12V, and 12V, respectively. Therefore, 12 V (first drive voltage) is applied to the DC motor 5 during the period from time T0 to time T1 (first drive mode).

  Next, at time T1, the control unit 64 turns off the first switch SW1 while keeping the second switch SW2 on, and this state continues for a period from time T1 to time T2. As a result, the voltages A, B, and C at the positions shown in FIG. 3 are 5V, 5V, and 5V, respectively. Therefore, 5 V (second drive voltage) is applied to the DC motor 5 during the period from time T1 to time T2 (second drive mode).

  Thereafter, the control unit 64 turns off the first switch SW1 and the second switch SW2 at time T2. As a result, as shown in FIG. 4, the voltages A, B, and C at the positions shown in FIG. 3 are 0V, 0V, and 0V, respectively. Therefore, no drive voltage is applied to the DC motor 5 (drive stop mode).

  The control panel on the electric automatic toilet cleaning device main body side is formed with two button switches for stool and urine, and when the button switch for stool is pressed, the output member 20 is a clock. When the urine button switch is pressed by rotating in the direction of the surrounding CW and the urine button switch is pressed, the output member 20 rotates in the counterclockwise direction of the CCW and flows a small amount of washing water. Such an operation can change the rotation direction of the output member 20 by changing the polarity of the voltage output from the power supply unit 61. In addition, the timing for turning on and off the first switch SW1 and the second switch SW2 may be different for stool and urine.

(Basic operation)
In the valve body drive device 1 according to the present embodiment, when an operation for flowing flush water to the button switch of the control panel is performed at time T0, the control unit 64 performs the operation from time T0 to time T1. Since the first switch SW1 and the second switch SW2 are turned on during the period, 12V (first drive voltage) is applied to the DC motor 5 during the period from time T0 to time T1. Accordingly, the DC motor 5 generates a relatively large torque and rotates the output member 20 clockwise CW against the spring force of the return spring 30. As a result, the output member 20 moves the valve body from the position for closing the drain hole to the position for opening. Meanwhile, the return spring 30 is deformed in the direction of expanding the diameter (first stage / first drive mode).

  Next, since the control unit 64 turns off the first switch SW1 while keeping the second switch SW2 on during the period from time T1 to time T2, the control unit 64 includes the period from time T1 to time T2. 5V (second drive voltage) is applied. Therefore, the DC motor 5 only generates a torque smaller than the period from time T0 to time T1, but further rotates the output member 20 clockwise CW against the spring force of the return spring 30. As a result, the output member 20 moves the valve body to a position where the drain hole is further opened. Meanwhile, the return spring 30 is deformed in the direction of expanding the diameter (second stage / second drive mode).

  Then, when the movable protrusion 541 of the fourth gear body 54 comes into contact with the contact portion 715 formed on the case body 71 during the period of time T1 to T2, the output member 20 stops rotating, and thereafter Until the time T2, the valve body stops at a predetermined position in the opening direction. During that time, the motor drive circuit 6 continues to apply a drive voltage of 5 V (second drive voltage) to the DC motor 5.

  Thereafter, the control unit 64 turns off the first switch SW1 and the second switch SW2 at time T2. As a result, since no driving voltage is applied to the DC motor 5, the output member 20 and the second gear body 52 cause the fourth gear body 54 to rotate counterclockwise CCW by the return force of the return spring 30, and the driving force It returns to the original position while reversing the gear used for the transmission mechanism 3. Therefore, the valve body returns to the state of closing the drain hole, and storage of water in the water storage tank is started (third stage / driving stop mode).

  It should be noted that the basic operation is the same even when an operation for flowing flush water for urine is performed on the button switch of the control panel at time T0, and the description thereof is omitted.

(Main effects of this form)
As described above, in this embodiment, the stopper 80 using the contact between the members is provided for the purpose of defining the position of the output member 20 in the opening direction, and the stopper 80 is used to open the output member 20 in the opening direction. Define the location. In the first drive mode, the motor drive circuit 6 supplies the first drive voltage to the DC motor 5 to shift the valve body from the closed state to the open state, and then in the second drive mode, the first drive voltage After the lower second drive voltage is supplied to the DC motor 5 to move the valve body further to the open state and the stopper 80 is operated, the second drive voltage is continuously applied to the DC motor 5. Here, the torque of the DC motor 5 is controlled by the drive voltage. For this reason, when the stopper 80 is operated, the output member 20 is driven with a low torque, so that when the stopper 80 is operated, a large collision noise is not generated and the member is not damaged. Further, in the second drive mode, since the second drive voltage lower than the first drive voltage is supplied to the DC motor 5, the heat generation of the DC motor 5 can be suppressed low.

  Further, since the first drive mode and the second drive mode are realized by the motor drive circuit 6, it is not necessary to provide a mechanical timer switch in the drive force transmission mechanism 3. In addition, since the drive voltage is applied even in the second drive mode, there is no problem in the operation of the valve body even when a deviation occurs between the position of the valve body and the timing when the first drive mode is switched to the second drive mode. . Therefore, switching control from the first drive mode to the second drive mode may be performed only by control from the motor drive circuit 6 side, and there is no need to provide a timer switch on the drive mechanism 2 side. Therefore, it is possible to simplify the incorporation of members and the lead wires. Furthermore, in the case of the DC motor 5, there is an advantage that there is less risk of electric shock compared to the AC motor.

  In addition, since the drainage is closed in the state where the valve body receives fluid pressure in the water tank, a large torque is required to shift the valve body from the closed state to the open state. Then, since it is the 1st drive mode which applies a high 1st drive voltage at this timing, a valve body can be smoothly changed from a closed state to an open state. Moreover, after the valve body has shifted to the open state, a relatively small torque is sufficient. However, in this embodiment, the second drive mode in which a low second drive voltage is applied at this timing. Therefore, low power consumption can be achieved.

  Furthermore, in this embodiment, the motor drive circuit 6 uses the resistor 627 (voltage dividing resistor) to generate the first drive voltage and the second drive voltage from a constant voltage, so that two voltages (first voltage) Even when generating one driving voltage and the second driving voltage), only one power source 611 is required. Therefore, the circuit configuration can be simplified, and the cost can be reduced.

  Furthermore, in this embodiment, in the driving force transmission mechanism 3, the driving force is transmitted from the DC motor 5 to the output member 20 only by the tooth wheel train, and the driving force transmission mechanism 3 does not include a sliding portion. Therefore, according to this embodiment, there is no problem caused by wear at the sliding portion. In addition, the driving force transmission mechanism 3 has a constant gear ratio and does not use an expensive deformed gear or the like for switching the gear ratio on the way, so that the cost can be reduced.

  The drive mechanism 2 includes a return spring 30 that displaces the output member 20 in the closing direction when the supply of the drive voltage from the motor drive circuit 6 to the DC motor 5 is stopped. In any case, the output member 20 can be movably displaced in the closing direction. Further, since the spring urges the output member 20 in the closing direction, the spring does not generate a large impact sound when the stopper 80 operates.

(Other embodiments)
In the above embodiment, as shown in FIGS. 2A and 2B, the sensor 68 sensitive to the temperature of the DC motor 5 is provided, and the motor drive circuit 6 is driven based on the detection result of the sensor 68. It is preferable to change the voltage. As the sensor 68, a thermistor can be used. Among these thermistors, when a PTC (Positive Temperature Coefficient) thermistor is used, the resistance value increases as the temperature rises. Therefore, for example, it is connected in series to the DC motor 5 as shown by the arrow P1 in FIG. When a NTC (Negative Temperature Coefficient) thermistor is used, the resistance value decreases as the temperature rises. For example, it may be connected to the DC motor 5 in parallel.

  In the above embodiment, the two voltages are generated by the voltage dividing resistor (resistor 627). However, the two voltages may be generated by a constant current diode, pulse control, a transformer, or the like.

  In the above-described embodiment, the driving force transmission mechanism 3 that does not use the slip portion is an example in which all of the driving force transmission mechanism 3 is configured as a gear. You may use what was used.

It is a longitudinal cross-sectional view of the valve body drive device to which this invention is applied. (A), (b) is explanatory drawing which shows the planar layout of the drive mechanism comprised in the valve body drive device shown in FIG. 1, respectively, and explanatory drawing of the motor drive circuit used for this drive mechanism. It is a circuit diagram of the motor drive circuit comprised in the valve body drive device shown in FIG. It is a wave form diagram of the drive voltage output from the motor drive circuit comprised in the valve body drive device shown in FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Valve body drive device 2 Drive mechanism 3 Drive force transmission mechanism 6 Motor drive circuit 5 DC motor 20 Output member 30 Return spring 80 Stopper 627 Resistor

Claims (7)

In a valve body driving device having an output member connected to a valve body for opening and closing a drain hole of a water storage tank, and a drive mechanism for driving the output member in an opening direction,
The drive mechanism includes a direct current motor as a drive source for driving the output member, a drive force transmission mechanism that transmits the output of the direct current motor to the output member, and a motor drive circuit that supplies a drive voltage to the direct current motor. And a stopper that defines a position in the opening direction of the output member by contact between the members,
The motor drive circuit includes a first drive mode for supplying a first drive voltage to the DC motor when the valve body transitions from a closed state to an open state, and after the valve body transitions to an open state, A second driving mode in which a second driving voltage lower than one driving voltage is supplied and the second driving voltage is applied to the DC motor even after the stopper is operated, and a voltage applied to the DC motor after a predetermined time has elapsed. And a drive stop operation for stopping the supply.   The valve body driving device according to claim 1, wherein the valve body closes the drain hole in a state in which fluid pressure is received in the water storage tank.   3. The valve body driving device according to claim 1, wherein in the driving force transmission mechanism, the driving force is transmitted from the DC motor to the output member only by a tooth wheel train.   The valve drive apparatus according to any one of claims 1 to 3, wherein the drive force transmission mechanism has a constant gear ratio at all times.   5. The motor drive circuit includes a voltage dividing resistor for generating the first drive voltage and the second drive voltage from a constant voltage. 6. The valve body drive device of description. A sensor sensitive to the temperature of the DC motor;
The valve body driving device according to any one of claims 1 to 5, wherein the motor driving circuit changes the driving voltage based on a detection result of the sensor.   7. The drive mechanism according to claim 1, further comprising a return spring that displaces the output member in a closing direction when supply of drive voltage from the motor drive circuit to the DC motor is stopped. The valve body drive device according to claim 1.

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