Granted Patent B2

US 12,449,057 · App. 18/832,401 · Granted Oct 21, 2025

Inventors: Hiroshi Hagimoto (Tokyo, JP); Yusuke Ishizuka (Tokyo, JP)

Assignee: FUJIKOKI CORPORATION

F16K31/046

Abstract

Claims (38)

1. An electric valve control device for controlling an electric valve including a valve body that has a valve port, a stepping motor that includes a rotor, a valve member that moves toward the valve port when the rotor rotates in a first direction and moves away from the valve port when the rotor rotates in a second direction, a first stopper mechanism that restricts rotation of the rotor in the first direction when the rotor is at a reference position, and a second stopper mechanism that restricts rotation of the rotor in the second direction when the rotor is at a full-open position, a state where the rotation of the rotor in the first direction is restricted being a first-direction-rotation restricted state, a state where the rotation of the rotor in the second direction is restricted being a second-direction-rotation restricted state, a number of pulses in design input to the stepping motor when the rotor is rotated from the full-open position to the reference position being a design number,

wherein

(1) the electric valve control device is configured to input pulses to the stepping motor to rotate the rotor in the second direction,

(2) the electric valve control device is configured to input pulses to the stepping motor to rotate the rotor in the first direction when the electric valve is in the second-direction-rotation restricted state while the rotor is rotated in the second direction,

(3) the electric valve control device is configured to obtain a number of pulses, which is an input number, input to the stepping motor in a period from the second-direction-rotation restricted state to the first-direction-rotation restricted state when the electric valve is in the first-direction-rotation restricted state while the rotor is rotated in the first direction,

(4) the electric valve control device is configured to determine that the rotor is able to rotate normally when the input number is greater than or equal to the design number and is smaller than or equal to an upper limit number that is greater than the design number, and

(5) the electric valve control device is configured to determine that the rotor is unable to rotate normally when the input number is smaller than the design number or is greater than the upper limit number.

2. The electric valve control device according to claim 1 ,

wherein the electric valve control device is configured to obtain a voltage generated in a stator of the stepping motor by rotation of the rotor, and

wherein the electric valve control device is configured to determine whether the electric valve is in the first-direction-rotation restricted state and whether the electric valve is in the second-direction-rotation restricted state, based on at least one of (i) an area of a waveform of the voltage, (ii) an amplitude of a wave periodically observed in the waveform of the voltage, and (iii) a periodic appearance of a new wave distinct from the wave periodically observed in the waveform of the voltage.

3. The electric valve control device according to claim 2 ,

wherein the stator includes an A-phase stator and a B-phase stator,

wherein driving currents corresponding to pulses input to the stepping motor are supplied to the A-phase and B-phase stators, and

wherein the electric valve control device is configured to obtain a voltage generated in one of the A-phase and B-phase stators when the driving current is supplied only to the other of the A-phase and B-phase stators.

4. An electric valve device comprising:

the electric valve; and

the electric valve control device according to claim 1 .

5. An electric valve control device for controlling an electric valve including a valve body that has a valve port, a stepping motor that includes a rotor, a valve member that moves toward the valve port when the rotor rotates in a first direction and moves away from the valve port when the rotor rotates in a second direction, a first stopper mechanism that restricts rotation of the rotor in the first direction when the rotor is at a reference position, and a second stopper mechanism that restricts rotation of the rotor in the second direction when the rotor is at a full-open position, a state where the rotation of the rotor in the first direction is restricted being a first-direction-rotation restricted state, a state where the rotation of the rotor in the second direction is restricted being a second-direction-rotation restricted state, a number of pulses in design input to the stepping motor when the rotor is rotated from the reference position to the full-open position being a design number,

wherein

(1) the electric valve control device is configured to input pulses to the stepping motor to rotate the rotor in the first direction,

(2) the electric valve control device is configured to input pulses to the stepping motor to rotate the rotor in the second direction when the electric valve is in the first-direction-rotation restricted state while the rotor is rotated in the first direction,

(3) the electric valve control device is configured to obtain a number of pulses, which is an input number, input to the stepping motor in a period from the first-direction-rotation restricted state to the second-direction-rotation restricted state when the electric valve is in the second-direction-rotation restricted state while the rotor is rotated in the second direction,

(4) the electric valve control device is configured to determine that the rotor is able to rotate normally when the input number is greater than or equal to the design number and is smaller than or equal to an upper limit number that is greater than the design number, and

(5) the electric valve control device is configured to determine that the rotor is unable to rotate normally when the input number is smaller than the design number or is greater than the upper limit number.

6. A method for controlling an electric valve including a valve body that has a valve port, a stepping motor that includes a rotor, a valve member that moves toward the valve port when the rotor rotates in a first direction and moves away from the valve port when the rotor rotates in a second direction, a first stopper mechanism that restricts rotation of the rotor in the first direction when the rotor is at a reference position, and a second stopper mechanism that restricts rotation of the rotor in the second direction when the rotor is at a full-open position, a state where the rotation of the rotor in the first direction is restricted being a first-direction-rotation restricted state, a state where the rotation of the rotor in the second direction is restricted being a second-direction-rotation restricted state, a number of pulses in design input to the stepping motor when the rotor is rotated from the full-open position to the reference position being a design number,

the method comprising:

(1) inputting pulses to the stepping motor to rotate the rotor in the second direction;

(2) inputting pulses to the stepping motor to rotate the rotor in the first direction when the electric valve is in the second-direction-rotation restricted state while the rotor is rotated in the second direction;

(3) obtaining a number of pulses, which is an input number, input to the stepping motor in a period from the second-direction-rotation restricted state to the first-direction-rotation restricted state when the electric valve is in the first-direction-rotation restricted state while the rotor is rotated in the first direction;

(4) determining that the rotor is able to rotate normally when the input number is greater than or equal to the design number and is smaller than or equal to an upper limit number that is greater than the design number; and

(5) determining that the rotor is unable to rotate normally when the input number is smaller than the design number or is greater than the upper limit number.

7. A method for controlling an electric valve including a valve body that has a valve port, a stepping motor that includes a rotor, a valve member that moves toward the valve port when the rotor rotates in a first direction and moves away from the valve port when the rotor rotates in a second direction, a first stopper mechanism that restricts rotation of the rotor in the first direction when the rotor is at a reference position, and a second stopper mechanism that restricts rotation of the rotor in the second direction when the rotor is at a full-open position, a state where the rotation of the rotor in the first direction is restricted being a first-direction-rotation restricted state, a state where the rotation of the rotor in the second direction is restricted being a second-direction-rotation restricted state, a number of pulses in design input to the stepping motor when the rotor is rotated from the reference position to the full-open position being a design number,

the method comprising:

(1) inputting pulses to the stepping motor to rotate the rotor in the first direction;

(2) inputting pulses to the stepping motor to rotate the rotor in the second direction when the electric valve is in the first-direction-rotation restricted state while the rotor is rotated in the first direction;

(3) obtaining a number of pulses, which is an input number, input to the stepping motor in a period from the first-direction-rotation restricted state to the second-direction-rotation restricted state when the electric valve is in the second-direction-rotation restricted state while the rotor is rotated in the second direction;

(4) determining that the rotor is able to rotate normally when the input number is greater than or equal to the design number and is smaller than or equal to an upper limit number that is greater than the design number; and

(5) determining that the rotor is unable to rotate normally when the input number is smaller than the design number or is greater than the upper limit number.

Assignments (1)

Priority Claims (1)

Continuity (1)

References Cited (16)