Electro-Photographic Type Image Forming Device and Photosensitive Unit Provided in the Same

• US 20120195633A1
• Filed: 01/26/2012
• Published: 08/02/2012
• Est. Priority Date: 01/31/2011
• Status: Active Grant

• Current Assignee: Brother Kogyo Kabushiki Kaisha (Brother Industries Limited)
• Original Assignee: Brother Kogyo Kabushiki Kaisha (Brother Industries Limited)
• Inventors: OKABE, Yasushi
• Granted Patent: US 8,798,496 B2
• Time in Patent Office: Days
• US Class Current: 399/116
• CPC Class Codes: G03G 21/16 Mechanical means for facilitating the maintenance of the apparatus, e.g. modular arrangements
• CPC Class Codes: G03G 21/1619 Frame structures
• CPC Class Codes: G03G 21/1671 for the photosensitive element
• CPC Class Codes: G03G 21/1853 the process cartridge being mounted perpendicular to the axis of the photosensitive member
• CPC Class Codes: G03G 2215/0119 Linear arrangement adjacent plural transfer points
• CPC Class Codes: G03G 2221/1654 Locks and means for positioning or alignment
• CPC Class Codes: G03G 2221/1684 using extractable subframes, e.g. on rails or hinges

Abstract

An image forming device includes a main casing and a photosensitive unit. The photosensitive unit has a first peripheral portion at a downstream side in an attaching direction provided with a first contact portion and has a second peripheral portion at an upstream side in the attaching direction provided with a second contact portion. The main casing includes a pair of side walls and first and second positioning members. The first and second positioning members span between the side walls. The first positioning member has a first positioning portion with which the first contact portion is contactable for positioning the photosensitive unit relative to the main casing. The second positioning member is positioned upstream of the first positioning member in the attaching direction. The second positioning member has a second positioning portion with which the second contact portion is contactable for positioning the photosensitive unit relative to the main casing.

Claims

1. An image forming device comprising:

a main casing; and

a photosensitive unit attachable to and detachable from the main casing and comprising;

a plurality of photosensitive bodies juxtaposedly arrayed and spaced away from each other in an array direction, each photosensitive body defining a longitudinal direction and having each end portion in the longitudinal direction, the array direction being an attaching direction of the photosensitive unit relative to the main casing; and

a pair of side plate sections supporting each end portion of each photosensitive body and spaced away from each other in the longitudinal direction, each side plate section having a first peripheral portion at a downstream side in the attaching direction provided with a first contact portion, and having a second peripheral portion at an upstream side in the attaching direction provided with a second contact portion;

the main casing comprising;

a pair of side walls spaced away from each other in the longitudinal direction;

a first positioning member extending in the longitudinal direction and spanning between the pair of side walls, the first positioning member having a first positioning portion with which the first contact portion is contactable for positioning the photosensitive unit relative to the main casing; and

a second positioning member extending in the longitudinal direction and spanning between the pair of side walls and positioned upstream of the first positioning member in the attaching direction, the second positioning member having a second positioning portion with which the second contact portion is contactable for positioning the photosensitive unit relative to the main casing.

2. The image forming device according to claim 1, wherein the first positioning member, the second positioning member, the first contact portion and the second contact portion have geometrical relationship such that the contact between the first positioning member and the first contact portion occurs simultaneously with the abutment between the second positioning member and the second contact portion.

3. The image forming device according to claim 1, further comprising:

a belt unit comprising;

a pair of rollers spaced away from each other in the array direction; and

an endless belt mounted on the pair of rollers including an upstream side roller and a downstream side roller in the attaching direction; and

a conveying portion positioned at upstream side of the belt unit in the attaching direction for conveying a sheet to a portion between the photosensitive body and the endless belt, the second positioning member being positioned between the conveying portion and the upstream side roller.

4. The image forming device according to claim 1, wherein the first contact portion is contactable with the first positioning portion in a first contacting direction, and the second contact portion is contactable with the second positioning portion in a second contacting direction;

and

the image forming device further comprising a pressure member configured to press the side plate sections with a first component force directing in the first contacting direction and with a second component force directing in the second contacting direction.

5. The image forming device according to claim 4, wherein the photosensitive unit further comprises a beam member spanning between the pair of side plate sections, the beam member having a protruding portion protruding outward from each side plate section in the longitudinal direction, the pressure member being configured to press each protruding portion with the first component force and the second component force.

6. The image forming device according to claim 1, wherein the pair of side plates section are a product obtained by punching and pressing a metal plate with using an identical punching press die.

7. The image forming device according to claim 1, wherein the first positioning member and the second positioning member are made from metal.

8. The image forming device according to claim 1, wherein the second positioning member has a cylindrical shape extending in the longitudinal direction.

9. A photosensitive unit detachably attached to a main casing of an image forming device in an attaching direction, comprising:

a plurality of photosensitive bodies juxtaposedly arrayed and spaced away from each other in an array direction, each photosensitive body defining a longitudinal direction and having each end portion in the longitudinal direction, the array direction being an attaching direction of the photosensitive unit relative to the main casing; and

a pair of side plate sections supporting each end portion of each photosensitive body and spaced away from each other in the longitudinal direction, each side plate section having a positioning contact portion positioned at an upstream side of an outer peripheral portion of the pair of side plate in the attaching direction, and having a contact portion positioned at the upstream side of the outer peripheral portion of the pair of side plates and independent of the positioning abutment portion, the positioning contact portion being contactable with a predetermined portion of the main casing for positioning the pair of side plate sections relative to the main casing, and the contact portion being contactable with a surface when the photosensitive unit is removed out of the main casing and placed on the surface.

10. The photosensitive unit according to claim 9, wherein the positioning contact portion is made from metal, and the contact portion is made from a resin.

11. The photosensitive unit according to claim 10, wherein each side plate section comprises an inner side plate made from the metal and an outer side plate positioned outside the inner side plate in the longitudinal direction and made from the resin, the positioning contact portion being provided in the inner side plate, and the contact portion being provided in the outer side plate.

12. The photosensitive unit according to claim 11, wherein the positioning contact portion and the contact portion are overlapped with each other in the longitudinal direction, the contact portion having a lower end lower than a lower end of the positioning contact portion.

13. The photosensitive unit according to claim 9, wherein the contact portion is configured such that when an entire photosensitive unit is placed on the surface, the entire photosensitive unit is inclined relative to the surface at an angle steeper than an inclination angle of the entire photosensitive unit when the photosensitive unit is accommodated in the main casing.