Toner cartridge, developing unit, process cartridge, and image forming apparatus

A toner cartridge attachable to and detachable from a developing unit of an image forming apparatus for forming an image on a recording material, the toner cartridge comprising:

• a toner housing portion that houses toner and that has a first end portion and a second end portion on an opposite side to the first end portion in a longitudinal direction of the toner cartridge;
• a conveyance member that is disposed in the interior of the toner housing portion, includes a rotary axis, and conveys the toner housed in the toner housing portion toward one end of the conveyance member in an axial direction of the rotary axis;
• a shutter that is incorporated to the first end portion of the toner housing portion in the axial direction so as to be capable of rotating relative to the toner housing portion about an axis parallel to the axial direction, and that includes a first opening that allows the toner housed in the toner housing portion to be discharged to the exterior from the interior of the toner housing portion, a closing portion for preventing the toner from moving to the exterior, and a first portion-to-be-engaged that projects in the axial direction;
• a cover that is fixed to the first end portion of the toner housing portion in the axial direction so as to cover the shutter and that includes a second opening which, together with the first opening, allows the toner housed in the toner housing portion to be discharged to the exterior from the interior of the toner housing portion;
• and
• a second portion-to-be-engaged that is provided to the first end portion of the toner housing portion in the axial direction,
• wherein the toner cartridge is configured such that by rotating the toner housing portion relative to the shutter in a state in which the first portion-to-be-engaged is engaged to a first engaging portion of the developing unit, relative positions of the cover and the shutter are displaced from first relative position, in which the closing portion opposes the second opening, to second relative position, in which the interior of the toner housing portion communicates with a reception port of the developing unit through the first opening and the second opening, and the second portion-to-be-engaged is engaged to a second engaging portion of the developing unit, thereby completing attachment of the toner cartridge to the developing unit,
• wherein the first portion-to-be-engaged and the second portion-to-be-engaged are configured such that before the toner housing portion is rotated relative to the shutter during attachment of the toner cartridge to the developing unit, the first portion-to-be-engaged and the second portion-to-be-engaged, in a case of being seen in the axial direction, are set in a first arrangement arranged side by side in an attachment direction in which the toner cartridge is attached to the developing unit, and after the toner housing portion is rotated relative to the shutter, the first portion-to-be-engaged and the second portion-to-be-engaged are set in a second arrangement arranged side by side in a direction that intersects the attachment direction, and
• wherein the first portion-to-be-engaged has a tapered shape in a case of being seen in the axial direction, the tapered shape being formed so that even though an angle of the first portion-to-be-engaged relative to the second portion-to-be-engaged in the first arrangement is displaced within a predetermined range, a width of the first portion-to-be-engaged and the second portion-to-be-engaged in an orthogonal direction to the attachment direction, in a case where the first portion-to-be-engaged and the second portion-to-be-engaged are projected in the attachment direction, does not vary.

A developing unit of an image forming apparatus for forming an image on a recording material, the developing unit comprising:

• a carrier that carries toner;
• a casing in which the carrier is incorporated, the casing having a first toner housing chamber for housing the toner;
• and
• a toner cartridge that can be attached to and detached from the casing,
• wherein the casing comprises:
• a reception port that receives toner supplied from the toner cartridge;
• and
• an attachment portion including a first engaging portion and a second engaging portion for engaging the toner cartridge to the casing,
• wherein the toner cartridge comprises:
• a toner housing portion that houses the toner and that has a first end portion and a second end portion on an opposite side to the first end portion in a longitudinal direction of the toner cartridge;
• a conveyance member that is disposed in the interior of the toner housing portion, includes a rotary axis, and conveys the toner housed in the toner housing portion toward one end of the conveyance member in an axial direction of the rotary axis;
• a shutter that is incorporated to the first end portion of the toner housing portion in the axial direction so as to be capable of rotating relative to the toner housing portion about an axis parallel to the axial direction, and that includes a first opening that allows the toner housed in the toner housing portion to be discharged to the exterior from the interior of the toner housing portion, a closing portion for preventing the toner from moving to the exterior, and a first portion-to-be-engaged that projects in the axial direction;
• a cover that is fixed to the first end portion of the toner housing portion in the axial direction so as to cover the shutter and that includes a second opening which, together with the first opening, allows the toner housed in the toner housing portion to be discharged to the exterior from the interior of the toner housing portion;
• and
• a second portion-to-be-engaged that is provided to the first end portion of the toner housing portion in the axial direction,
• wherein the developing unit is configured such that by rotating the toner housing portion relative to the shutter in a state in which the first portion-to-be-engaged is engaged to the first engaging portion of the developing unit, relative positions of the cover and the shutter are displaced from first relative position, in which the closing portion opposes the second opening, to second relative position, in which the interior of the toner housing portion communicates with the reception port of the developing unit through the first opening and the second opening, and the second portion-to-be-engaged is engaged to the second engaging portion of the developing unit, thereby completing attachment of the toner cartridge to the developing unit, and
• wherein the developing unit includes a biasing member that exerts a biasing force for generating relative rotation between the cover and the shutter in a direction for displacing the relative positions thereof from the second relative position to the first relative position.

A developing unit provided in an image forming apparatus for forming an image on a recording material, the developing unit comprising:

• a carrier that carries toner;
• a casing in which the carrier is incorporated, the casing having a first toner housing chamber for housing the toner;
• and
• a toner cartridge that can be attached to and detached from the casing,
• wherein the casing comprises:
• a reception port that receives toner supplied from the toner cartridge;
• and
• an attachment portion including a first engaging portion and a second engaging portion for engaging the toner cartridge to the casing,
• wherein the toner cartridge comprises:
• a toner housing portion that houses the toner and that has a first end portion and a second end portion on an opposite side to the first end portion in a longitudinal direction of the toner cartridge;
• a conveyance member that is disposed in the interior of the toner housing portion, includes a rotary axis, and conveys the toner housed in the toner housing portion toward one end of the conveyance member in an axial direction of the rotary axis;
• a shutter that is incorporated to the first end portion of the toner housing portion in the axial direction so as to be capable of rotating relative to the toner housing portion about an axis parallel to the axial direction, and that includes a first opening that allows the toner housed in the toner housing portion to be discharged to the exterior from the interior of the toner housing portion, a closing portion for preventing the toner from moving to the exterior, and a first portion-to-be-engaged that projects in the axial direction;
• a cover that is fixed to the first end portion of the toner housing portion in the axial direction so as to cover the shutter and that includes a second opening which, together with the first opening, allows the toner housed in the toner housing portion to be discharged to the exterior from the interior of the toner housing portion;
• and
• a second portion-to-be-engaged that is provided to the first end portion of the toner housing portion in the axial direction,
• wherein the first portion-to-be-engaged and the second portion-to-be-engaged, in a case of being seen in the axial direction, are configured to be capable of taking a first arrangement arranged side by side in an attachment direction in which the toner cartridge is attached to the developing unit, and a second arrangement arranged side by side in a direction that intersects the attachment direction,
• wherein the toner cartridge is configured such that in a case where the toner cartridge is to be attached to the developing unit, by rotating the toner housing portion relative to the shutter in a state in which the first portion-to-be-engaged and the second portion-to-be-engaged are inserted into the attachment portion in the first arrangement and the first portion-to-be-engaged is engaged to the first engaging portion, relative positions of the cover and the shutter are displaced from first relative position, in which the closing portion opposes the second opening, to second relative position, in which the interior of the toner housing portion communicates with the reception port through the first opening and the second opening, and the second portion-to-be-engaged is engaged to the second engaging portion after entering the second arrangement, thereby completing attachment of the toner cartridge to the developing unit,
• wherein the attachment portion, in a case of being seen in the axial direction, includes a pair of guide walls opposing each other in an orthogonal direction to the attachment direction, and
• wherein the pair of guide walls are configured such that opposing wall surfaces on the downstream side in the attachment direction form the first engaging portion, one wall surface on the upstream side in the attachment direction extends along the attachment direction and is connected to the first engaging portion, and the other wall surface on the upstream side in the attachment direction includes a tapered wall surface that inclines so as to increase the width of the attachment portion on the upstream side in the attachment direction.