FUJIKOKI CORPORATION

An electric valve control device is configured to (i) start inputting pulse to a stepping motor to rotate a rotor in a first direction, (ii) obtain a rotation angle of the rotor based on a rotation angle signal and a position of the rotor based on a magnetic-flux-density signal each time pulse is input to the stepping motor, and (iii) stop inputting pulse when a change in the rotation angle of the rotor matches a change pattern information and a position of the rotor is a proximity position or a position nearer a reference position than is the proximity position. The change pattern information includes a change in the rotation angle indicating rotation in a second direction.

An electric valve includes a valve body that has a valve port and a valve seat enclosing the valve port, a valve member that faces the valve port, a valve stem, and a stepping motor. The valve stem has an external thread. The valve body has an internal thread into which the external thread is screwed. The external thread and the internal thread constitute a screw-feed mechanism. The valve stem is coaxially secured to a magnet rotor of the stepping motor. The lower end of the valve stem is connected to the valve member. When the magnet rotor rotates in a valve closing direction, the valve member moves toward the valve port. When the valve member comes into contact with the valve seat, the valve member is restricted from moving toward the valve port.

A motor-operated valve includes a driving shaft that has an external thread, a guide member that has an internal thread into which the external thread is screwed, and a planetary gear mechanism that reduces the rotational speed of a rotor and transmits rotation of the rotor to the driving shaft. Where L represents the lead of the external thread, and K represents the speed-reduction ratio of the planetary gear mechanism, the motor-operated valve 1 satisfies expressions [1] and [2] below: 0.04 K ≤ L ≤ 0.1 K ⁢ and [ 1 ] 30 ≤ K ≤ 100 . [ 2 ]

An electromagnetic valve includes: a solenoid around which a coil is wound; an attractor that is disposed inside the solenoid; a plunger that is attracted to the attractor by energization of the solenoid and is connected to a valve shaft (valve body); a pipe that is provided inside the solenoid and houses the plunger; and a housing that includes a first support disposed to overlap with one end of the solenoid in an axial direction and a second support disposed to overlap with the other end of the solenoid in the axial direction, and that has, in the first support and the second support, a first attachment hole and a second attachment hole into which the pipe is fitted, respectively. The first attachment hole abuts an outer circumference of the pipe on one side in a radial direction thereof.

An electric valve control device is configured to (i) start inputting pulse to a stepping motor to rotate a rotor in a first direction, (ii) obtain a rotation angle of the rotor based on a rotation angle signal and a position of the rotor based on a magnetic-flux-density signal each time pulse is input to the stepping motor, and (iii) stop inputting pulse when a change in the rotation angle of the rotor matches a change pattern information and a position of the rotor is a proximity position or a position nearer a reference position than is the proximity position. The change pattern information includes a change in the rotation angle indicating rotation in a second direction.

An electric valve control device inputs pulses to a stepping motor to rotate a rotor in a second direction; inputs pulses to the stepping motor to rotate the rotor in a first direction when the electric valve is in a second-direction-rotation restricted state; obtains the number of pulses (an input number (Xi)) input to the stepping motor from the second-direction-rotation restricted state to a first-direction-rotation restricted state when the electric valve is in the first-direction-rotation restricted state while the rotor rotates in the first direction; determines that the rotor can rotate normally when the input number (Xi) is greater than or equal to a design number (Xd) and is smaller than or equal to an upper limit number (Xu); and determines that the rotor cannot rotate normally when the input number (Xi) is smaller than the design number (Xd) or is greater than the upper limit number (Xu).

In an electrically operated valve including a valve main body having a valve chamber communicating with an inflow passage for refrigerant and an outflow passage for refrigerant, a valve body moving forward and backward for a valve seat formed within the valve chamber and changing a refrigerant flow rate, an electric motor driving the valve body, a board controlling the electric motor, and a board storage portion including a case storing the board, the board has a fixing hole fixing the board within the case, the case has a support projection fixed into the fixing hole and supporting the board within the case, and the support projection is integrally formed with the case portion. The support projection is preferably provided with a step portion and the board is preferably held by the step portion and a pressing projection disposed in a back surface of a lid occluding the case.

An electric valve control device inputs a pulse to a stepping motor to rotate a rotor in a first direction. The electric valve control device obtains a voltage generated in a stator by rotation of the rotor. The electric valve control device determines whether an electric valve is in a first-rotation restricted state where the rotation of the rotor in the first direction is restricted, based on a degree of difference between a waveform of the voltage and a reference waveform of the voltage.

A valve gear includes a valve main body having a valve chamber in an inner portion, a valve body having a flow channel space in an inner portion and changing a flow rate for fluid by being rotated and driven within the valve chamber, a first flow channel hole formed in the valve main body and communicated with the flow channel space to allow the fluid to pass through, a second flow channel hole formed in the valve main body changing a communicated state with the flow channel space by a rotational displacement position of the valve body and allowing the fluid to pass through when being communicated with the flow channel space, and a transmission mechanism including a valve body drive shaft transmitting a drive force for rotating the valve body to the valve body. Rotation axes of the valve body and the valve body drive shaft are orthogonal.