Cartridge and image forming device

1. A cartridge configured to accommodate developer, comprising:

a detected member configured to rotate in a first direction about a first rotational axis extending in an axial direction, the detected member being configured to be detected by an external first sensor, the detected member including a receiving part and a first detected part; and

a drive-force transmission member configured to transmit a drive force to the detected member upon receipt of an external drive force, the drive-force transmission member having a peripheral surface formed with gear teeth, the receiving part of the detected member being configured to engage the gear teeth of the drive-force transmission member to receive the drive force therefrom, a portion of the first detected part and a portion of the receiving part being arranged at the same position as each other in the axial direction,

wherein the detected member is configured to rotate from a first position to a second position, the first detected part at the first position being capable of receiving the drive force from the drive-force transmission member, the first detected part at the second position being incapable of receiving the drive force from the drive-force transmission member, the first detected part at the second position being contacted by the first sensor.

2. The cartridge as claimed in claim 1 , wherein the first detected part constitutes a part of the receiving part.

3. The cartridge as claimed in claim 1 , wherein the detected member further includes a second detected part provided upstream of the first detected part in the first direction, and

wherein a portion of the second detected part and a portion of the receiving part are arranged at the same position as each other in the axial direction.

4. The cartridge as claimed in claim 1 , further comprising:

a casing configured to accommodate the developer; and

a cover member configured to cover the detected member,

wherein:

the detected member further includes a first engaging part;

the detected member is configured to rotate to a second position after the first detected part is detected by the first sensor, the receiving part being separated from the drive-force transmission member at the second position; and

one of the casing and the cover member is provided with a first engaged part engageable with the first engaging part of the detected member at the second position, the first engaged part engaging the first engaging part restricting the detected member from rotating in a second direction opposite to the first direction.

5. The cartridge as claimed in claim 4 , wherein the first engaging part is configured to resiliently deform while the drive force is transmitted from the drive-force transmission member to the receiving part, the first engaging part being configured to restore its original shape when the drive force transmission from the drive-force transmission member to the receiving part is cancelled, and

wherein the restoration of the first engaging part causes the detected member to rotate to the second position.

6. The cartridge as claimed in claim 4 , wherein the first engaged part includes an opposing surface configured to oppose the first engaging part in a direction intersecting the axial direction, the opposing surface including:

a first contact surface configured to be contacted by the first engaging part while the drive force is transmitted from the drive-force transmission member to the receiving part; and

a second contact surface configured to be contacted by the first engaging part when the drive force transmission from the drive-force transmission member to the receiving part is cancelled,

wherein the first engaging part protrudes in a direction intersecting the axial direction is resiliently deformable toward the first rotational axis, the first engaging part including a contact end configured to contact the first engaged part, and

wherein the first contact surface is sloped to approach the first rotational axis toward downstream in the first direction, and the second contact surface is sloped to extend away from the first rotational axis toward downstream in the first direction.

7. The cartridge as claimed in claim 4 , wherein the detected member further includes a second engaging part, the detected member being configured to be placed at a fourth position before the receiving part receives the drive force from the drive-force transmission member, the receiving part being separated from the drive-force transmission member in the fourth position, and

wherein the casing includes a second engaged part engageable with the second engaging part of the detected member at the fourth position, the second engaged part engaging the second engaging part restricting the detected member from rotating in the first direction.

8. The cartridge as claimed in claim 7 , wherein the first engaging part also functions as the second engaging part.

9. An image forming device comprising:

a main body provided with a first sensor and a second sensor;

a photosensitive-drum cartridge provided with a photosensitive member for carrying an electrostatic latent image thereon, the photosensitive-drum cartridge being detachable from and attachable to the main body, the second sensor being configured to detect whether the photosensitive-drum cartridge is attached to the main body; and

a cartridge configured to accommodate developer therein, the cartridge being mountable on and removable from the photosensitive-drum cartridge, the cartridge comprising:

a detected member configured to rotate in a first direction about a first rotational axis extending in an axial direction, the detected member being configured to be detected by the first sensor, the detected member including a receiving part and a first detected part; and

a drive-force transmission member configured to transmit a drive force to the detected member upon receipt of the drive force from the main body, the drive-force transmission member having a peripheral surface formed with gear teeth, the receiving part of the detected member being configured to engage the gear teeth of the drive-force transmission member to receive the drive force therefrom, a portion of the first detected part and a portion of the receiving part being arranged at the same position as each other in the axial direction, the detected member being configured to rotate from a first position to a second position, the first detected part at the first position being capable of receiving the drive force from the drive-force transmission member, the first detected part at the second position being incapable of receiving the drive force from the drive-force transmission member, the first detected part at the second position being contacted by the first sensor, the main body being configured to input the drive force to the cartridge after the second sensor detects whether the photosensitive-drum cartridge is attached to the main body.