Angle detector

1. An angle detector, comprising:

a rotating member configured to rotate with a shaft inserted therethrough;

a housing rotatably supporting the rotating member;

a detector configured to detect a rotating angle of the rotating member with respect to the housing;

an urging member urging the rotating member in a rotating direction of the rotating member;

an engagement portion provided on the housing; and

an engaged portion provided on the rotating member and configured to be brought into engagement with the engagement portion by urged by the urging member

wherein the urging member is a spring.

2. The angle detector as set forth in claim 1 , wherein:

the rotating member is disposed in the housing so as to rotate within an angle range which is smaller than 360 degrees,

the housing includes a main body portion and a lid portion,

the engagement portion has a projection projected from an inner face of the housing,

the engaged portion has a cutout formed on the rotating member, and

the projection is configured to be inserted in the cutout, in a case where the rotating member is angled with respect to the housing within the angle range when the lid portion is attached to the main body portion.

3. The angle detector as set forth in claim 2 , wherein:

the urging member includes a torsion coil spring,

one end portion of the torsion coil spring is installed on the housing, and

the other end portion of the torsion coil spring is installed on the rotating member.

4. The angle detector as set forth in claim 3 , wherein:

the other end portion of the torsion coil spring is fit in a hole formed on the rotating member parallel to a rotating axis of the rotating member.

5. The angle detector as set forth in claim 1 , wherein:

the rotating member is disposed in the housing so as to rotate within an angle range which is smaller than 360 degrees,

the housing includes a main body portion and a lid portion,

the engagement portion has a cutout formed on an inner face of the housing,

the engaged portion has a projection projected from the rotating member, and

the projection is configured to be inserted in the cutout, in a case where the rotating member is angled with respect to the housing within the angle range when the lid portion is attached to the main body portion.

6. The angle detector as set forth in claim 5 , wherein:

the urging member includes a torsion coil spring,

one end portion of the torsion coil spring is installed on the housing, and

the other end portion of the torsion coil spring is installed on the rotating member.

7. The angle detector as set forth in claim 6 , wherein:

the other end portion of the torsion coil spring is fit in a hole formed on the rotating member parallel to a rotating axis of the rotating member.

8. An angle detector, comprising:

a rotating member configured to rotate with a shaft inserted therethrough;

a housing rotatably supporting the rotating member;

a detector configured to detect a rotating angle of the rotating member with respect to the housing;

an urging member urging the rotating member in a rotating direction of the rotating member;

an engagement portion provided on the housing; and

an engaged portion provided on the rotating member and configured to be brought into engagement with the engagement portion by urged by the urging member,

wherein:

the rotating member is disposed in the housing so as to rotate within an angle range which is smaller than 360 degrees,

the housing includes a main body portion and a lid portion,

the engagement portion has a projection projected from an inner face of the housing,

the engaged portion has a cutout formed on the rotating member, and

the projection is configured to be inserted in the cutout, in a case where the rotating member is angled with respect to the housing within the angle range when the lid portion is attached to the main body portion.

9. The angle detector as set forth in claim 8 , wherein:

the urging member includes a torsion coil spring,

one end portion of the torsion coil spring is installed on the housing, and

the other end portion of the torsion coil spring is installed on the rotating member.

10. The angle detector as set forth in claim 9 , wherein:

the other end portion of the torsion coil spring is fit in a hole formed on the rotating member parallel to a rotating axis of the rotating member.

11. An angle detector, comprising:

a rotating member configured to rotate with a shaft inserted therethrough;

a housing rotatably supporting the rotating member;

a detector configured to detect a rotating angle of the rotating member with respect to the housing;

an urging member urging the rotating member in a rotating direction of the rotating member;

an engagement portion provided on the housing; and

an engaged portion provided on the rotating member and configured to be brought into engagement with the engagement portion by urged by the urging member,

wherein:

the rotating member is disposed in the housing so as to rotate within an angle range which is smaller than 360 degrees,

the housing includes a main body portion and a lid portion,

the engagement portion has a cutout formed on an inner face of the housing,

the engaged portion has a projection projected from the rotating member, and

the projection is configured to be inserted in the cutout, in a case where the rotating member is angled with respect to the housing within the angle range when the lid portion is attached to the main body portion.

12. The angle detector as set forth in claim 11 , wherein:

the urging member includes a torsion coil spring,

one end portion of the torsion coil spring is installed on the housing, and

the other end portion of the torsion coil spring is installed on the rotating member.

13. The angle detector as set forth in claim 12 , wherein:

the other end portion of the torsion coil spring is fit in a hole formed on the rotating member parallel to a rotating axis of the rotating member.