Valve device and system in which the valve device is mounted
AssigneeAisan Kogyo Kabushiki Kaisha
InventorMakoto Mase
Life of this patent
Estimating the term…
Abstract
A valve device that includes a valve body; a valve shaft configured to rotate the valve body; a coil spring being electrically conductive and configured to be twisted with rotation of the valve body and the valve shaft; a first conductive member being electrically conductive and facing an inner circumferential surface or an outer circumferential surface of the coil spring in a radial direction of the coil spring; and a first detector configured to detect at least one of a rotation angle of the valve body or a rotation angle of the valve shaft based on an electrostatic capacitance between the coil spring and the first conductive member, the electrostatic capacitance changing according to a state of the coil spring that changes with the rotation of the valve body and the valve shaft.
Claims2
A valve device comprising:
- a valve body;
- a valve shaft configured to rotate the valve body;
- a coil spring being electrically conductive and configured to be twisted with rotation of the valve body and the valve shaft;
- a second detector configured to detect at least one of a rotation angle of the valve body or a rotation angle of the valve shaft based on an inductance of the coil spring, the inductance changing according to a state of the coil spring that changes with the rotation of the valve body and the valve shaft;
- and
- at least one second conductive member being electrically conductive and arranged on at least one of:
- an inner side relative to an inner circumferential surface of the coil spring or an outer side relative to an outer circumferential surface of the coil spring in a radial direction of the coil spring;
- the at least one second conductive member defines a circumferential wall extending in an axial direction of the valve shaft, and
- the circumferential wall faces the coil spring over a whole area from one end to another end of the coil spring in an axial direction of the coil spring.
A system in which a valve device is mounted, the valve device comprising:
- a valve body;
- a valve shaft configured to rotate the valve body:
- a coil spring being electrically conductive and configured to be twisted with rotation of the valve body and the valve shaft;
- a second detector configured to detect at least one of a rotation angle of the valve body or a rotation angle of the valve shaft based on an inductance of the coil spring, the inductance changing according to a state of the coil spring that changes with the rotation of the valve body and the valve shaft, and
- at least one second conductive member being electrically conductive and arranged on at least one of:
- an inner side relative to an inner circumferential surface of the coil spring or an outer side relative to an outer circumferential surface of the coil spring in a radial direction of the coil spring;
- the system comprising two power sources, wherein
- the valve device further comprises a motor configured to be operated by direct current and to rotate the valve shaft, and
- one of the two power sources is configured to apply a voltage to the motor and another of the two power sources is configured to apply a voltage to at least one of the coil spring or the at least one second conductive member to generate a potential difference between the coil spring and the at least one second conductive member.
Dependencies are inferred from the claim text.