State detection mechanism

Abstract

A state detection mechanism includes a movable member, a spring member, a fringe section, and a stopper member. The spring member displaces the movable member arranged at the first predetermined position to a second predetermined position by applying restoration force in a D direction to the movable member. The fringe section restricts the displacement by abutting to a protrusion member formed on the movable member arranged at the first predetermined position. The stopper member restricts rotation of the movable member, which rotates around an axis that extends in a D direction, by abutting to the protrusion member formed on the movable member arranged at the first predetermined position. When torque is transmitted to the movable member from a shaft, the movable member rotates around an axis that extends in the D direction, and the protrusion member and the stopper member abut to each other. Load caused by the torque is applied to a section of this abutment and destroys the protrusion member. With this arrangement, the state detection mechanism which allows for detection of a state of a replaceable member can prevent the occurrence of wrong detection.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic diagram illustrating a cross section of a part of a photosensitive cartridge including a state detection mechanism of an embodiment of the present invention, and illustrating a state where a movable member is arranged at a first predetermined position.

FIG. 2 is an exploded perspective view of the state detection mechanism of the embodiment of the present invention.

FIG. 3 is a schematic diagram illustrating a cover included in the state detection mechanism of the embodiment of the present invention.

FIG. 4 is a schematic diagram illustrating a cross section of a part of the photosensitive cartridge including the state detection mechanism of the embodiment of the present invention, illustrating a state where the movable member is arranged at a second predetermined position.

FIG. 5 is a schematic diagram illustrating an arrangement inside an image formation apparatus into which the photosensitive cartridge including the state detection mechanism of the embodiment of the present invention is installed.

FIG. 6( a) is a schematic diagram of a cross section of a conventional initial detection mechanism in a state where an axis body is in contact with a sensor.

FIG. 6( b) is a schematic diagram of a cross section of the conventional initial detection mechanism in a state where the axis body is away from the sensor.

Claims

1. A state detection mechanism comprising: a supporting mechanism provided in a replaceable member attached detachably to a main apparatus; anda movable member supported by the supporting mechanism, wherein:(i) the movable member is arranged at a first predetermined position when the replaceable member is in an unused state in which the replaceable member has never been used by the main apparatus, and (ii) the movable member is arranged at a second predetermined position when the unused state is cancelled, the second predetermined position being away from the first predetermined position; andthe main apparatus detects the unused state by detecting the movable member arranged at the first predetermined position,the state detection mechanism further comprising:torque transmission member for transmitting torque to the movable member by driving force from the main apparatus when the replaceable member is used in the main apparatus; anda protrusion member formed on the movable member, wherein:the supporting mechanism includes: a movable-member displacement member for (a) supporting the movable member and (b) displacing the movable member arranged at the first predetermined position to the second predetermined position by applying a pressure towards the second predetermined position to the movable member;a first restriction member for restricting the displacement by abutting to the protrusion member formed on the movable member arranged at the first predetermined position; anda second restriction member for restricting rotation of the movable member in a direction identical to a direction of rotation caused by the torque by abutting to the protrusion member formed on the movable member arranged at the first predetermined position; andsaid protrusion member is destroyed by load caused by the torque exerted on a section where the second restriction member and the protrusion member abut to each other, when the torque is transmitted to the movable member.

2. The state detection mechanism as set forth in claim 1, wherein: the movable-member displacement member is an elastic member which (a) elastically supports the movable member and (b) applies restoration force towards the second predetermined position as the pressure to the movable member arranged at the first predetermined position.

3. The state detection mechanism as set forth in claim 1, wherein: said protrusion member is made of a material whose hardness is lower than that of the second restriction member.

4. The state detection mechanism as set forth in claim 1, wherein: the supporting mechanism further includes a supporting mechanism main unit which is fit into the replaceable member and provided with the first restriction member and the second restriction member;the supporting mechanism main unit includes a first engaging member;the supporting mechanism main unit is fit into the replaceable member by engaging the first engaging member with a second engaging member formed on the replaceable member; andthe first engaging member is destroyed by a predetermined amount of load or greater load which is exerted on the first engaging member and caused by tensile force given to the supporting member main unit in a direction parting from the replaceable member.

5. The state detection mechanism as set forth in claim 1, wherein: the main apparatus is an image formation apparatus and the replaceable member is a process cartridge of the image formation apparatus.