Image forming apparatus to which a process cartridge is detachably mountable and process cartridge comprising a rotation fulcrum portion

An electrophotographic image forming apparatus to which a process cartridge is detachably mountable for forming an image on a recording medium, said electrophotographic image forming apparatus comprising:

• a) mounting means for detachably mounting the process cartridge, the process cartridge including:
• an electrophotographic photosensitive drum;
• process means acting on the electrophotographic photosensitive drum;
• a rotation fulcrum portion which constitutes a supported portion of the process cartridge, the supported portion being supported by an image forming apparatus main body when the process cartridge is mounted to said image forming apparatus main body and which is parallel to the electrophotographic photosensitive drum;
• and
• an abutting portion which is provided in a position spaced apart from the rotation fulcrum portion and which moves when the process cartridge is rotated around the rotation fulcrum portion when the process cartridge is mounted to said image forming apparatus main body to thereby enable a laser beam shielding mechanism provided in said image forming apparatus main body,
• wherein said mounting means has a guide member configured and positioned to guide the rotation fulcrum portion along a rotation center axial direction and cartridge swinging means for supporting the process cartridge at a position spaced apart from said guide member to swing the process cartridge around said guide member;
• b) said laser beam shielding mechanism in which a laser shutter is opened and closed by movement of the abutting portion by process cartridge mounting and detaching operations;
• and
• c) conveying means for conveying the recording medium.

A process cartridge detachably mountable to an electrophotographic image forming apparatus main body, the electrophotographic image forming apparatus main body including an openable and closable member, laser beam emitting means for emitting a laser beam, a shutter movable between a shielding position in which the shutter shields an optical path through which the laser beam emitted from the laser beam emitting means passes and an open position in which the shutter is retracted from the shielding position to allow the laser beam to pass, a first member configured and positioned to move the shutter, and a second member, said process cartridge comprising:

• an electrophotographic photosensitive drum;
• process means acting on said electrophotographic photosensitive drum;
• and
• an abutting portion configured and positioned to move the first member to an engagement position, in which the first member is engageable with the second member, in accordance with an operation of mounting said process cartridge in a positioning location in the image forming apparatus main body, wherein said process cartridge is insertable in the image forming apparatus main body, and once inserted descends about a rotation fulcrum portion to thereby be mounted in the positioning location,
• wherein mounting of said process cartridge in the positioning location moves the first member to the engagement position, and wherein the second member moves the first member positioned in the engagement position to move the shutter to the open position in association with closing of the openable and closable member after said process cartridge is mounted in the positioning location.

An electrophotographic image forming apparatus to which a process cartridge is detachably mountable for forming an image on a recording medium, said electrophotographic image forming apparatus comprising:

• (i) an openable and closable member;
• (ii) laser beam emitting means for emitting a laser beam;
• (iii) a shutter movable between a shielding position in which said shutter shields an optical path through which the laser beam emitted from said laser beam emitting means passes and an open position in which said shutter is retracted from said shielding position to allow the laser beam to pass;
• (iv) a first member configured and positioned to move said shutter;
• (v) a second member;
• (vi) a mounting portion to which the process cartridge is detachably mountable, the process cartridge including:
• an electrophotographic photosensitive drum;
• process means acting on the electrophotographic photosensitive drum;
• and
• an abutting portion configured and positioned to move said first member to an engagement position, in which said first member is engageable with said second member, in accordance with an operation of mounting the process cartridge in a positioning location in a main body of said image forming apparatus, wherein the process cartridge is insertable in the main body of said image forming apparatus, and once inserted, the process cartridge descends about a rotation fulcrum portion to thereby be mounted in the positioning location;
• and
• (vii) conveying means for conveying the recording medium,
• wherein mounting of the process cartridge in the positioning location moves said first member to the engagement position, and wherein said second member moves said first member positioned in the engagement position to move said shutter to the open position in association with closing of said openable and closable member.