Abstract: A power generating portion formed of a rotor and a stator is provided. The rotor is formed of a ring incorporating a permanent magnet and an impeller. The rotor is regarded as a turbine. An actual flow rate is estimated from a present angular velocity of the turbine and a present torque of the power generating portion, a torque of the power generating portion in which the estimated actual flow rate corresponds to a setting flow rate is calculated and the torque of the power generating portion is controlled based on the calculated torque and a magnetic pole position of the turbine. A measured value detected by a position sensor is used as the magnetic pole position of the turbine, however, when it is determined that reliability does not exist in the position sensor, an estimated value is used.

Abstract: A power generating portion formed of a rotor and a stator is provided. The rotor is formed of a ring incorporating a permanent magnet and an impeller. The rotor is regarded as a turbine. An actual flow rate of fluid flowing in a flow path is estimated from a present angular velocity of the turbine and a present torque of the power generating portion, a torque of the power generating portion in which the estimated actual flow rate corresponds to a setting flow rate is calculated and the torque of the power generating portion is controlled based on the calculated torque and a magnetic pole position of the turbine. The magnetic pole position of the turbine is estimated based on a present phase voltage value and a present phase current value of the power generating portion and a present winding temperature of the power generating portion.

Abstract: A table indicating a relationship between a differential pressure across a valve unit and a torque that is to be outputted by a motor (an output torque) is stored in a table storing portion. A valve opening controlling portion and a torque controlling portion are provided in a controlling portion. The valve opening controlling portion uses the actual opening ?pv, from the valve opening detector, as the valve opening measured value, and sends a driving command to the motor so as to cause the valve opening measured value ?pv to match the valve opening setpoint ?sp. The torque controlling portion acquires, from the table, a torque corresponding to the differential pressure ?P across the valve unit, detected by the differential pressure detecting portion, and sends, to the motor, a command (a torque output command) to cause outputting of the torque that has been acquired.

Abstract: A power generating portion formed of a rotor and a stator is provided. The rotor is formed of a ring incorporating a permanent magnet and an impeller. The rotor is regarded as a turbine. An actual flow rate of fluid flowing in a flow path is estimated from a present angular velocity of the turbine and a present torque of the power generating portion, a torque of the power generating portion in which the estimated actual flow rate corresponds to a setting flow rate is calculated and the torque of the power generating portion is controlled based on the calculated torque and a magnetic pole position of the turbine. The magnetic pole position of the turbine is estimated based on a present phase voltage value and a present phase current value of the power generating portion and a present winding temperature of the power generating portion.

Abstract: A power generating portion formed of a rotor and a stator is provided. The rotor is formed of a ring incorporating a permanent magnet and an impeller. The rotor is regarded as a turbine. An actual flow rate is estimated from a present angular velocity of the turbine and a present torque of the power generating portion, a torque of the power generating portion in which the estimated actual flow rate corresponds to a setting flow rate is calculated and the torque of the power generating portion is controlled based on the calculated torque and a magnetic pole position of the turbine. A measured value detected by a position sensor is used as the magnetic pole position of the turbine, however, when it is determined that reliability does not exist in the position sensor, an estimated value is used.

Abstract: A table indicating a relationship between a differential pressure across a valve unit and a torque that is to be outputted by a motor (an output torque) is stored in a table storing portion. A valve opening controlling portion and a torque controlling portion are provided in a controlling portion. The valve opening controlling portion uses the actual opening ?pv, from the valve opening detector, as the valve opening measured value, and sends a driving command to the motor so as to cause the valve opening measured value ?pv to match the valve opening setpoint ?sp. The torque controlling portion acquires, from the table, a torque corresponding to the differential pressure ?P across the valve unit, detected by the differential pressure detecting portion, and sends, to the motor, a command (a torque output command) to cause outputting of the torque that has been acquired.

Abstract: In a method for evaluating degradation of a potentiometer, a plurality of evaluation items, from minor to major, are established as evaluation items for degradation in performance prior to failure of a potentiometer. The degradation of the potentiometer in performance of the plurality of evaluation items is evaluated in terms of stages, in a specific sequence.

Abstract: An electric actuator includes a motor, an electricity storing body, a manual operating unit, a switch and a resetting unit. In a state wherein a controlled element has arrived at a first opening and a supply of power to the motor from the electricity storing body is cut off, the motor and the controlled element are in a non-linked state only while a button is pushed. The switch keeps a supply path of electric power open when the button has been pressed once. The resetting unit closes the switch at a point in time that the controlled element that is driven by the motor arrives at a specific second opening at a time of restoration of the external power supply in a state wherein the non-linked state of the motor and the controlled element by the button has been undone.

Abstract: An electric actuator has a motor, an electricity storing body, a switch and a resetting unit. The switch is provided in a supply path of electric power from the electricity storing body to the motor. The switch opens the supply path for electric power from the electricity storing body to the motor, in response to an instruction from an operator. The resetting unit is operated through receiving a supply of electric power from the external power supply when the external power supply has been restored from being cut off. The resetting unit closes the switch that is provided in the supply path of electric power from the electricity storing body to the motor.

Abstract: An electric actuator has a motor, an electricity storing body, a switch, a setting unit, a resetting unit and a setting-off unit. The switch is provided in a supply path for electric power from the electricity storing body to the motor. The switch opens and closes the supply path. The setting unit is operated through receiving a supply of electric power from the electricity storing body in response to an instruction from an operator. The setting unit opens the switch. The resetting unit is operated through r a supply of electric power from the external power supply when the external power supply has been restored from being cut off. The resetting unit closes the switch that is provided in the supply path. The setting-off unit sets off the supply of electric power from the external power supply to the resetting unit after a specific delay time has elapsed.

Abstract: An electric actuator has a switch, a setting unit and a resetting unit. The switch is provided in a supply path of electric power from an electricity storing body to a motor. The switch opens and closes the supply path. The setting unit is operated through receiving a supply of electric power from the electricity storing body in response to an instruction from an operator. The setting unit opens the switch provided in the supply path for electric power from the electricity storing body to the motor. The resetting unit is operated through receiving a supply of electric power from an external power supply when the external power supply has been restored from being cut off. The resetting unit closes the switching unit provided in the supply path of electric power from the electricity storing body to the motor.

Abstract: An electric actuator includes a motor, an electricity storing body, a manual operating unit, a switch and a resetting unit. In a state wherein a controlled element has arrived at a first opening and a supply of power to the motor from the electricity storing body is cut off, the motor and the controlled element are in a non-linked state only while a button is pushed. The switch keeps a supply path of electric power open when the button has been pressed once. The resetting unit closes the switch at a point in time that the controlled element that is driven by the motor arrives at a specific second opening at a time of restoration of the external power supply in a state wherein the non-linked state of the motor and the controlled element by the button has been undone.

Abstract: An electric actuator is provided having the same configuration whether used as an ordinary electric actuator or as an electric actuator having an emergency shutoff function. A portion for supplying power during a power failure, a power failure detection circuit, and a motor power supply switching circuit are provided in a module detachably coupled to the electric actuator. When failure of primary power is not detected, the power is sent to the electric actuator by the motor power supply switching circuit. When failure of the primary power is detected, secondary power is sent to the electric actuator by the motor power supply switching circuit. In addition, notification of the power failure is sent from the module to the control board of the electric actuator, via a relay connector.

Abstract: An electric actuator has a switch, a setting unit and a resetting unit. The switch is provided in a supply path of electric power from an electricity storing body to a motor. The switch opens and closes the supply path. The setting unit is operated through receiving a supply of electric power from the electricity storing body in response to an instruction from an operator. The setting unit opens the switch provided in the supply path for electric power from the electricity storing body to the motor. The resetting unit is operated through receiving a supply of electric power from an external power supply when the external power supply has been restored from being cut off. The resetting unit closes the switching unit provided in the supply path of electric power from the electricity storing body to the motor.

Abstract: An electric actuator has a motor, an electricity storing body, a switch and a resetting unit. The switch is provided in a supply path of electric power from the electricity storing body to the motor. The switch opens the supply path for electric power from the electricity storing body to the motor, in response to an instruction from an operator. The resetting unit is operated through receiving a supply of electric power from the external power supply when the external power supply has been restored from being cut off. The resetting unit closes the switch that is provided in the supply path of electric power from the electricity storing body to the motor.

Abstract: An electric actuator has a motor, an electricity storing body, a switch, a setting unit, a resetting unit and a setting-off unit. The switch is provided in a supply path for electric power from the electricity storing body to the motor. The switch opens and closes the supply path. The setting unit is operated through receiving a supply of electric power from the electricity storing body in response to an instruction from an operator. The setting unit opens the switch. The resetting unit is operated through r a supply of electric power from the external power supply when the external power supply has been restored from being cut off. The resetting unit closes the switch that is provided in the supply path. The setting-off unit sets off the supply of electric power from the external power supply to the resetting unit after a specific delay time has elapsed.

Abstract: In a method for evaluating degradation of a potentiometer, a plurality of evaluation items, from minor to major, are established as evaluation items for degradation in performance prior to failure of a potentiometer. The degradation of the potentiometer in performance of the plurality of evaluation items is evaluated in terms of stages, in a specific sequence.

Abstract: An electric actuator is provided having the same configuration whether used as an ordinary electric actuator or as an electric actuator having an emergency shutoff function. A power failure detection circuit, a portion for supplying power during a power failure, a motor power supply switching circuit, a power failure control signal generation circuit, and a control signal switching circuit are provided in a module detachably coupled to the electric actuator. When failure of the primary power is not detected, the motor power supply switching circuit and the control signal switching circuit send the primary power and a signal indicative of a setting of an aperture of a valve of the electric actuator, respectively, to the electric actuator. When failure of the primary power is detected, the motor power supply switching circuit and the control signal switching circuit send the secondary power and the signal indicative of the setting of the aperture during a power failure to the electric actuator.

Abstract: An electric actuator is provided having the same configuration whether used as an ordinary electric actuator or as an electric actuator having an emergency shutoff function. A relay connector is provided in an electric actuator. When a module for supplying power during a power failure is connected, a first drive output signal generated by a motor drive circuit is relayed to the module and a motor power switching circuit is provided in the module. When the AC power supply does not fail, the first drive output signal sent from the electric actuator is selected; when the AC power supply fails, the second drive output signal generated by the motor drive circuit is selected and is sent to the AC motor of the electric actuator, via the relay connector.

Abstract: An electric actuator is provided having the same configuration whether used as an ordinary electric actuator or as an electric actuator having an emergency shutoff function. A portion for supplying power during a power failure, a power failure detection circuit, and a motor power supply switching circuit are provided in a module detachably coupled to the electric actuator. When failure of primary power is not detected, the power is sent to the electric actuator by the motor power supply switching circuit. When failure of the primary power is detected, secondary power is sent to the electric actuator by the motor power supply switching circuit. In addition, notification of the power failure is sent from the module to the control board of the electric actuator, via a relay connector.