US 5,028,966 A · Image-forming machine

Abstract

An image-forming machine having a main body and a process unit adapted to be detachably mounted on the main body. The process unit includes a first unit having a developing device and a charging corona discharger and a second unit having a rotating drum and a cleaning device. The developing device comprises a magnetic brush mechanism comprised of a hollow cylindrical sleeve and a permanent magnet disposed within the sleeve and a blade adapted to be brought into press contact with the surface of the sleeve and to decrease sufficiently the thickness of the developer layer on the sleeve surface. The cleaning device includes an elastic blade adapted to be brought into press contact with a photosensitive member disposed on the surface of the rotating drum. The toner removed from the surface of the photosensitive member by the action of the elastic blade is recovered into an interior space of the rotating drum.

Claims24

Dependent claims

An image-forming machine comprising a main body and a process unit adapted to be detachably mounted on the main body, said process unit including an image-bearing means having a photosensitive means on its surface and a developing device for developing a latent electrostatic image formed on the surface of the photosensitive member;

in which
the process unit is comprised of a first unit on which the developing device is mounted and a second unit on which the image-bearing means is mounted,
the first unit and the second unit can be mounted on, and detached from, each other, and
in detaching the process unit mounted on the main body, the first unit cannot be detached from the main body unless the second unit is detached from the first unit and removed from the main body.

1 more element

An image-forming machine comprising a main body comprised of a lower housing and an upper openable-closable housing mounted on the lower housing for free pivoting between an open position and a closed position about a central pivot axis and a process unit mounted detachably on the main body, the process unit including an image-bearing means having a photosensitive member on its surface, in which:

a main body of the machine further has provided thereon a supporting-guiding means for freely pivoting between an elevated position and a lowered position downwardly from the elevated position about the central pivot axis,
a guide portion extending in the mounting direction of the process unit formed on the supporting-guiding means, and
when the upper openable-closable housing is held at the open position and the supporting-guiding means is held at the elevated position, the guide portion of the supporting-guiding means extends toward an open space between the lower housing and the upper openable-closable housing, and thus the process unit is detachably mounted on the main body of the machine along the guide portion.

An image-forming machine comprising a main body comprised of a lower housing and an upper openable-closable housing mounted for free pivoting between an open position and a closed position and a process unit mounted detachably on the main body, the process unit including an image-bearing means having a photosensitive member on its surface and a developing means for developing a latent electrostatic image formed on the surface of the photosensitive member;

in which
the process unit is comprised of a first unit on which the developing device is mounted and a second unit on which the image-bearing member is mounted,
the first unit and the second unit can be mounted on, and detached from, each other,
the second unit further has provided therein a cover means for protecting the surface of the image-bearing means, the shape of the bottom portion of the cover means corresponding to that of part of the lower housing,
a guide channel extending in a predetermined direction is defined in the first unit, and in the second unit, a guide protrusion corresponding to the guide channel is provided, and
to mount the process unit detachably on the main body of the machine, the first unit is mounted on the main body of the machine, the second unit is then placed on said part of the lower housing, and the first unit is pivoted downwardly whereby the guide protrusion provided in the second unit is detachably received in the guide channel defined in the first unit, and thereafter by moving the guide protrusion along the guide channel, the second unit is held at a predetermined position, and then the cover means is detached from the second unit.

3 more elements

An image-forming machine comprising a rotating drum having a photosensitive member on its surface, in which a shaft portion provided at one end of the rotating drum is supported detachably and rotatably on a receiving means provided in the main body of the machine, and by mounting the rotating drum on the main body of the machine, a driven gear provided at one end portion of the rotating drum is drivingly coupled to a driving coupling gear drivingly coupled to a driving source provided in the main body of the machine;

wherein the receiving means for supporting the shaft portion provided at one end of the rotating drum defines a nearly semicircular receiving surface covering part of the upper part of the shaft portion, and a force transmitted from the driving coupling gear to the driven gear at the time of drivingly coupling the driving gear to the driven gear is substantially supported by the receiving surface of the receiving means;
wherein a first end portion of the receiving surface contacts the shaft portion at a site which is above a horizontal line passing through the center of the shaft portion of the rotating drum and which is upstream in a first rotating direction of the rotating drum,
another end portion of the receiving surface is provided with an escape portion,
whereby, when the rotating drum is rotated in the first direction, a force directed upwardly obliquely toward an upstream side in the rotating direction of the rotating drum acts on the shaft portion of the rotating drum, owing to a force to be transmitted from the driving coupling gear to the driven gear.

1 more element

Dependencies are inferred from the claim text.

Image-forming machine

Life of this patent

Image-forming machine

Life of this patent

Abstract

Claims24