Position sensing device, rotational actuator having the same, shift-by-wire system having the rotational actuator, and method for detecting position of movable member
AssigneeDenso Corporation
InventorTakuya Yoshida
Life of this patent
Estimating the term…
Abstract
A pulse signal output unit sends three-phase pulse signals according to movement of the movable member. A counter unit adds a first predetermined value or a second predetermined value to a count value or subtracts the first predetermined value or the second predetermined value from the count value, according to a combination of the pulse signals appearing when all the pulse signals are normal and a combination of the pulse signals appearing when one of the pulse signals malfunctions. A position detection unit detects the position of the movable member according to the count value.
Claims7
A position sensing device configured to detect a position of a movable member being rotatable or linearly movable, the position sensing device comprising:
- a pulse signal output unit configured to send three-phase pulse signals, which have predetermined phase differences thereamong, according to a rotation or a linear movement of the movable member;
- a counter unit configured to store a count value and configured
- to add a first predetermined value to the count value or to subtract the first predetermined value from the count value and
- to add a second predetermined value to the count value or to subtract the second predetermined value, which is different from the first value, from the count value, according to
- an in-normal pattern, which is a combination of the pulse signals appearing when all the three-phase pulse signals are normal, and
- an in-malfunction pattern, which is a combination of the pulse signals appearing when one of the pulse signals among the three-phase pulse signals malfunctions;
- and
- a position detection unit configured to detect the position of the movable member according to the count value.
A method for detecting a position of a movable member being rotatable or linearly movable, the method comprising:
- sensing three-phase pulse signals, which are sent with a rotation or a linear movement of the movable member;
- determining that a combination of the pulse signals is in an in-normal pattern when all the three-phase pulse signals are normal;
- determining that the combination of the pulse signals is in an in-malfunction pattern when one of the three-phase pulse signals malfunctions;
- adding a first predetermined value to a count value or subtracting the first predetermined value from the count value, or adding a second predetermined value to the count value or subtracting the second predetermined value from the count value, according to the in-normal pattern and the in-malfunction pattern;
- and
- acquiring the position of the movable member according to the count value.
Dependencies are inferred from the claim text.