# US 5,708,922 A · Guide means and electrophotographic image forming apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 5,708,922 A - Document ID: US5708922A - Status: Granted - Kind: A - Application number: 08/637,155 - Filed: 1996-04-24 - Granted: 1998-01-13 - Earliest claimed: 1995-04-26 - Assignees: Canon Kabushiki Kaisha - Inventors: Jun Azuma; Yoshihisa Ibaraki - Web page: https://patentgrep.com/patent/US5708922A ## CPC - G03G 21/1832: {Shielding members, shutter, e.g. light, heat shielding, prevention of toner scattering} - G03G 21/1633: {using doors or covers (G03G21/1638 takes precedence)} - G03G 21/1647: {Mechanical connection means} - G03G 21/1671: {for the photosensitive element} - G03G 21/1853: {the process cartridge being mounted perpendicular to the axis of the photosensitive member} - G03G 2221/1609: protective arrangements for preventing damage - G03G 2221/1654: Locks and means for positioning or alignment - G03G 2221/169: Structural door designs - G03G: ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY ## Abstract A guide member according to the present invention is constituted by a guide portion for guiding a positioning projection provided on a process cartridge when the process cartridge is removably mounted to an image forming apparatus, a shutter guide portion for guiding a shutter projection provided on a shutter member opening/closing a transfer opening of the process cartridge when the process cartridge is removably mounted to the image forming apparatus, and a regulating portion against which the shutter projection abuts if the process cartridge is tried to be inserted into the image forming apparatus in an erroneous manner. ## Claims ### Claim 1 A guide member for guiding a process cartridge when the process cartridge is removably mounted to a main body of an image forming apparatus, wherein said guide member is attached to the main body of the image forming apparatus and wherein the process cartridge includes an electrophotographic photosensitive member and at least one process means for acting on the electrophotographic photosensitive member, said guide member comprising: (a) a cartridge guide portion for guiding a positioning projection, provided on the process cartridge, when the process cartridge is mounted to the main body of the image forming apparatus; (b) a shutter guide portion for guiding a shutter projection provided on a shutter member of the process cartridge, the shutter member covering a transfer opening of the process cartridge, to open the shutter member when the process cartridge is mounted to the main body of the image forming apparatus; and (c) a regulating portion against which the shutter projection abuts when the process cartridge is inserted into the main body of the image forming apparatus in an erroneous state. ### Claim 2 (depends on 1) A guide member according to claim 1, wherein said shutter guide portion and said regulating portion are formed integrally. ### Claim 3 (depends on 1) A guide member according to claim 1, further comprising a locking pawl for attaching said guide member to the main body of the image forming apparatus. ### Claim 4 (depends on 1) A guide member according to claim 1, further comprising a bent portion for preventing foreign matter from dropping. ### Claim 5 (depends on 1) A guide member according to claim 1, wherein said cartridge guide portion, said shutter guide portion and said regulating portion are integrally molded from a plastic material. ### Claim 6 An electrophotographic image forming apparatus to which a process cartridge including an electrophotographic photosensitive member and at least one process member acting on the electrophotographic photosensitive member is removably mounted, and which forms an image on a recording medium, said image forming apparatus comprising: (a) a guide member for guiding the process cartridge when the process cartridge is removably mounted to a main body of said image forming apparatus, said guide member including a cartridge guide portion for guiding a positioning projection provided on the process cartridge when the process cartridge is mounted to said main body of said image forming apparatus, a shutter guide portion for guiding a shutter projection provided on a shutter member of the process cartridge, the shutter member covering a transfer opening of the process cartridge, to open the shutter member when the process cartridge is mounted to said main body of said image forming apparatus, and a regulating portion against which the shutter projection abuts when the process cartridge is inserted into said main body of said image forming apparatus in an erroneous state; (b) a fixing member for fixing a toner image transferred from the electrophotographic photosensitive member to the recording medium; and (c) a convey member for conveying the recording medium. ### Claim 7 (depends on 6) An image forming apparatus according to claim 6, wherein said shutter guide portion and said regulating portion are formed integrally. ### Claim 8 (depends on 6) An image forming apparatus according to claim 6, further comprising a locking pawl for attaching said guide member to said main body of said image forming apparatus. ### Claim 9 (depends on 6) An image forming apparatus according to claim 6, further comprising a bent portion for preventing foreign matter from dropping. ### Claim 10 (depends on 6) An image forming apparatus according to claim 6, wherein said cartridge guide portion, said shutter guide portion and said regulating portion are integrally molded from plastic material. ### Claim 11 A guide member for guiding a process cartridge when the process cartridge is removably mounted to a main body of an image forming apparatus, wherein said guide member is attached to the main body of the image forming apparatus and wherein the process cartridge includes an electrophotographic photosensitive member and at least one process member acting on the electrophotographic photosensitive member, said guide member comprising: (a) a cartridge guide portion for guiding a positioning projection, provided on the process cartridge, when the process cartridge is mounted to the main body of the image forming apparatus, said cartridge guide portion having a positioning recess for positioning the positioning projection; (b) a shutter guide portion for guiding a shutter projection provided on a shutter member of the process cartridge, the shutter member covering a transfer opening of the process cartridge, to open the shutter member when the process cartridge is mounted to the main body of the image forming apparatus; (c) a regulating portion against which the shutter projection abuts when the process cartridge is inserted into the main body of the image forming apparatus in an erroneous state where a front portion and a rear portion of the process cartridge are reversed; and (d) a locking pawl member for attaching said guide member to the main body of the image forming apparatus. ### Claim 12 (depends on 11) A guide member according to claim 11, further comprising a bent portion for preventing foreign matter from dropping, said bent portion being positioned at a lower portion of said guide member when said guide member is attached to the image forming apparatus. ### Claim 13 (depends on 11) A guide member according to claim 11, wherein said cartridge guide portion is an elongated slot, and said positioning recess is disposed contiguous with said elongated slot. ### Claim 14 (depends on 11) A guide member according to claim 11, wherein said shutter guide portion is an inclined surface, and said regulating portion is disposed in a vicinity of said inclined surface. ### Claim 15 (depends on 11) A guide member according to claim 11, wherein said locking pawl member is locked to at least one locking hole provided in a metal chassis of the main body of the image forming apparatus when said guide member is attached thereto. ### Claim 16 (depends on 11, 12, 13, 14) A guide member according to one of claims 11 to 14, wherein said cartridge guide portion, said positioning recess, said shutter guide portion and said regulating portion are integrally molded from plastic material. ### Claim 17 An electrophotographic image forming apparatus to which a process cartridge including an electrophotographic photosensitive member and at least one process member acting on the electrophotographic photosensitive member is removably mounted, and which forms an image on a recording medium, said image forming apparatus comprising: (a) a guide member for guiding the process cartridge when it is removably mounted to a main body of said image forming apparatus, said guide member including a cartridge guide portion for guiding a positioning projection provided on the process cartridge when the process cartridge is mounted to said main body of said image forming apparatus, said cartridge guide portion having a positioning recess for positioning the positioning projection, a shutter guide portion for guiding a shutter projection provided on a shutter member of the process cartridge, the shutter member covering a transfer opening of the process cartridge, to open the shutter member when the process cartridge is mounted to said main body of said image forming apparatus, a regulating portion against which the shutter projection abuts when the process cartridge is inserted into said main body of said image forming apparatus in an erroneous state where a front portion and a rear portion of the process cartridge are reversed, and a locking pawl member for attaching said guide member to said main body of said image forming apparatus; (b) fixing means for fixing a toner image transferred from the electrophotographic photosensitive member to the recording medium; and (c) convey means for conveying the recording medium. ### Claim 18 (depends on 17) An image forming apparatus according to claim 17, further comprising a bent portion for preventing foreign matter from dropping, said bent portion being positioned at a lower portion of said guide member when said guide member is attached to said main body of said image forming apparatus. ### Claim 19 (depends on 17) An image forming apparatus according to claim 17, wherein said cartridge guide portion is an elongated slot, and said positioning recess is disposed contiguous with said elongated slot. ### Claim 20 (depends on 17) An image forming apparatus according to claim 17, wherein said shutter guide portion is an inclined surface, and said regulating portion is disposed in a vicinity of said inclined surface. ### Claim 21 (depends on 17) An image forming apparatus according to claim 17, wherein said locking pawl member is locked to at least one locking hole provided in a metal chassis of said main body of said image forming apparatus when said guide member is attached thereto. ### Claim 22 (depends on 17, 18, 19, 20) An image forming apparatus according to one of claims 17 to 20, wherein said cartridge guide portion, said positioning recess, said shutter guide portion and said regulating portion are integrally molded from plastic material. ### Claim 23 (depends on 1) A guide member according to claim 1, wherein said process means is at least one of developing means for developing a latent image formed on the photosensitive member, charging means for charging the photosensitive member, and cleaning means for removing toner remaining on the photosensitive member. ### Claim 24 (depends on 6, 17) An image forming apparatus according to claim 6 or 17, wherein the process member is at least one of a developing roller for developing a latent image formed on the photosensitive member, a charging roller for charging the photosensitive member, and a cleaning blade for removing toner remaining on the photosensitive member. ### Claim 25 (depends on 11) A guide member according to claim 11, wherein the process member is at least one of a developing roller for developing a latent image formed on the photosensitive member, a charging roller for charging the photosensitive member, and a cleaning blade for removing toner remaining on the photosensitive member.