# US 2014/0153977 A1 · Image Forming Apparatus and Fixing Apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0153977 A1 - Document ID: US20140153977A1 - Status: Published application - Kind: A1 - Application number: 14/091,417 - Filed: 2013-11-27 - Published: 2014-06-05 - Earliest claimed: 2012-11-30 - Assignees: Brother Kogyo Kabushiki Kaisha - Inventors: Atsushi Ozawa; Noboru Suzuki; Tatsuya Koyama; Takuji Matsuno - Web page: https://patentgrep.com/patent/US20140153977A1 ## CPC - G03G 21/1638: {directed to paper handling or jam treatment} - G03G 15/6573: {Feeding path after the fixing point and up to the discharge tray or the finisher, e.g. special treatment of copy material to compensate for effects from the fixing} - G03G 2215/00675: Mechanical copy medium guiding means, e.g. mechanical switch - G03G: ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY ## Abstract An image forming apparatus includes a fixing unit, discharge unit, first and second guides, and top cover. The discharge unit is disposed obliquely above a heating member of the fixing unit. The first guide extends from a position above the heating member toward the discharge unit and has an upstream portion in a conveying direction of an image-fixed sheet. The second guide is disposed above the heating member and faces the upstream portion. The second guide defines an upper portion of the conveying path. A part of the second guide faces the upstream portion in the first position, and exposes the upstream portion in the second position. The top cover is movable between an open position where the second guide is exposed and a closed position where the second guide is covered. The first guide has a guide surface sloping downward in the conveying direction. ## Claims ### Claim 1 An image forming apparatus comprising: a main body; a fixing unit including a heating member and configured to thermally fix a developer image deposited on a sheet to provide an image-fixed sheet; a sheet discharge unit disposed at a position obliquely above the heating member and configured to discharge the image-fixed sheet out of the main body; a first conveying guide extending from a position above the heating member toward the sheet discharge unit, the first conveying guide defining a lower portion of a conveying path for guiding the image-fixed sheet toward the sheet discharge unit, the first conveying guide having an upstream portion disposed at an upstream side of a conveying direction of the image-fixed sheet; a second conveying guide disposed above the heating member and facing the upstream portion of the first conveying guide, the second conveying guide defining an upper portion of the conveying path, at least a part of the second conveying guide being movable between a first position and a second position, the at least a part of the second conveying guide facing the upstream portion of the first conveying guide in the first position, the at least a part of the second conveying guide exposed the upstream portion of the first conveying guide in the second position; and a top cover movable between an open position in which the second conveying guide is exposed and a closed position in which the second conveying guide is covered, wherein the first conveying guide has a guide surface sloping downward toward a downstream side of the conveying direction. ### Claim 2 (depends on 1) The image forming apparatus according to claim 1, wherein the fixing unit includes: an electronic part; a frame member supporting the heating member; and a cover covering the electronic part and at least a part of the frame member. ### Claim 3 (depends on 2) The image forming apparatus according to claim 2, wherein the first conveying guide and the cover are integrally formed. ### Claim 4 (depends on 2) The image forming apparatus according to claim 2, wherein the electronic part is disposed between the frame member and the cover and spaced apart from the heating member, the electronic part being configured to detect a temperature of the heating member. ### Claim 5 (depends on 1) The image forming apparatus according to claim 1, wherein the first conveying guide further includes a guide roller configured to rotate when further conveying the image-fixed sheet has been conveyed from the fixing unit. ### Claim 6 (depends on 5) The image forming apparatus according to claim 5, wherein the sheet discharge unit includes a first discharge roller and a second discharge roller that are configured to convey the image-fixed sheet interposed therebetween, a nip between the first discharge roller and the second discharge roller being positioned below a horizontal plane tangent to a top of the guide roller. ### Claim 7 (depends on 1) The image forming apparatus according to claim 1, wherein the first conveying guide further includes a plurality of guide rollers juxtaposed in a widthwise direction orthogonal to the conveying direction of the image-fixed sheet, each of the plurality of guide rollers being configured to rotate when further conveying the image-fixed sheet has been conveyed from the fixing unit; wherein the sheet discharge unit includes a plurality of first discharge rollers and a plurality of second discharge rollers each corresponding to one of the plurality of first discharge rollers, the plurality of first discharge rollers being arranged in the widthwise direction, the plurality of second discharge rollers being juxtaposed in the widthwise direction, each first discharge roller and corresponding second discharge roller being configured to convey the image-fixed sheet interposed therebetween, a nip between the each first discharge roller and the corresponding second discharge roller being positioned below a horizontal plane tangent to tops of the plurality of guide rollers. ### Claim 8 (depends on 6) The image forming apparatus according to claim 6, wherein a position of the guide roller is same as a position of the first discharge roller and a position of the second discharge roller in a widthwise direction orthogonal to the conveying direction of the image-fixed sheet. ### Claim 9 (depends on 6) The image forming apparatus according to claim 6, wherein the second discharge roller is disposed above the first discharge roller; wherein the sheet discharge unit further includes a third discharge roller disposed downstream the first discharge roller in the conveying direction, the third discharge roller and the second discharge roller configured to convey the image-fixed sheet interposed therebetween. ### Claim 10 (depends on 1) The image forming apparatus according to claim 1, wherein the fixing unit includes a frame member configured to support the heating member and having a hole, wherein the second conveying guide has one end portion and another end portion in a widthwise direction orthogonal to the conveying direction of the image-fixed sheet, the one end portion being engaged with the frame member by being inserted in the hole, the another end portion being fixed to the frame member by a screw. ### Claim 11 (depends on 10) The image forming apparatus according to claim 10, wherein the engagement of the one end portion in the hole has play in the widthwise direction. ### Claim 12 An image forming apparatus comprising: a main body; a sheet discharge unit configured to discharge a sheet out of the main body; a fixing unit configured to thermally fix a developer image deposited on a sheet to provide an image-fixed sheet; a first conveying guide defining a lower portion of a conveying path for guiding the image-fixed sheet toward the sheet discharge unit; a second conveying guide defining an upper portion of the conveying path and facing the first conveying guide, the second conveying guide having a downstream end spaced apart from the sheet discharge unit, the downstream end of the second conveying guide and the sheet discharge unit defining a space therebetween; and a top cover disposed on a top of the main body and configured to move between an open position in which the space is exposed and a closed position in which the space is covered. ### Claim 13 (depends on 12) The image forming apparatus according to claim 12, wherein the sheet discharge unit is provided on the top cover; wherein the top cover has a guide rib configured to guide the image-fixed sheet passing between the first conveying guide and the second conveying guide toward the sheet discharge unit. ### Claim 14 (depends on 12) The image forming apparatus according to claim 12, wherein at least a part of the second conveying guide is movable between a first position and a second position, wherein in the first position, the at least a part of the second conveying guide is configured to guide the image-fixed sheet, and in the second position, the at least a part of the second conveying guide exposes the first conveying guide. ### Claim 15 (depends on 12) The image forming apparatus according to claim 12, wherein the fixing unit includes: an electronic part; a heating member configured to heat the developer image deposited on the sheet; a frame member supporting the heating member; and a cover covering the electronic part and at least a part of the frame member. ### Claim 16 (depends on 15) The image forming apparatus according to claim 15, wherein the first conveying guide and the cover are integrally formed. ### Claim 17 (depends on 15) The image forming apparatus according to claim 15, wherein the electronic part is disposed between the frame member and the cover and spaced apart from the heating member, the electronic part being configured to detect a temperature of the heating member. ### Claim 18 (depends on 12) The image forming apparatus according to claim 12, wherein the first conveying guide further includes a guide roller configured to rotate when further conveying the image-fixed sheet has been conveyed from the fixing unit. ### Claim 19 (depends on 16) The image forming apparatus according to claim 16, wherein the sheet discharge unit includes a first discharge roller and a second discharge roller that are configured to convey the image-fixed sheet interposed therebetween, a nip between the first discharge roller and the second discharge roller being positioned below a horizontal plane tangent to a top of the guide roller. ### Claim 20 (depends on 19) The image forming apparatus according to claim 19, wherein the first conveying guide further includes a plurality of guide rollers juxtaposed in a widthwise direction orthogonal to the conveying direction of the image-fixed sheet, each of the plurality of guide rollers being configured to rotate when further conveying the image-fixed sheet has been conveyed from the fixing unit; wherein the sheet discharge unit includes a plurality of first discharge rollers and a plurality of second discharge rollers each corresponding to one of the plurality of first discharge rollers, the plurality of first discharge rollers being arranged in the widthwise direction, the plurality of second discharge rollers being juxtaposed in the widthwise direction, each first discharge roller and corresponding second discharge roller being configured to convey the image-fixed sheet interposed therebetween, a nip between the each first discharge roller and the corresponding second discharge roller being positioned below a horizontal plane tangent to tops of the plurality of guide rollers. ### Claim 21 (depends on 19) The image forming apparatus according to claim 19, wherein a position of the guide roller is same as a position of the first discharge roller and a position of the second discharge roller in a widthwise direction orthogonal to the conveying direction of the image-fixed sheet. ### Claim 22 (depends on 19) The image forming apparatus according to claim 19, wherein the second discharge roller is disposed above the first discharge roller; wherein the sheet discharge unit further includes a third discharge roller disposed downstream the first discharge roller in the conveying direction of the image-fixed sheet, the third discharge roller and the second discharge roller configured to convey the image-fixed sheet interposed therebetween. ### Claim 23 (depends on 12) The image forming apparatus according to claim 12, wherein the fixing unit includes: a heating member configured to heat a developer deposited on the sheet; and a frame member configured to support the heating member and having a hole, wherein the second conveying guide has one end portion and another end portion in a widthwise direction orthogonal to the conveying direction of the image-fixed sheet, the one end portion being engaged with the frame member by being inserted in the hole, the another end portion being fixed to the frame member by a screw. ### Claim 24 (depends on 23) The image forming apparatus according to claim 23, wherein the engagement of the one end portion in the hole has play in the widthwise direction. ### Claim 25 A fixing apparatus comprising: a heating rotary body having an outer surface and configured to thermally fix a developer deposited on a sheet; a thermistor configured to detect a temperature of the heating rotary body, the thermistor facing the outer surface of the heating rotary body and separated from the heating rotary body; and a case including: a supporting part supporting the heating rotary body to rotate; and a cover part covering the thermistor and at least a part of the supporting part. ### Claim 26 (depends on 25) The fixing apparatus according to claim 25, wherein the cover part is detachably mounted on the supporting part. ### Claim 27 (depends on 25) The fixing apparatus according to claim 25, wherein the thermistor is disposed below a horizontal plane passing through a rotational center of the heating rotary body and upstream of a vertical plane passing through the rotational center with respect to the rotational direction of the heating rotary body. ### Claim 28 (depends on 25) The fixing apparatus according to claim 25, wherein the case includes a guide rib configured to guide a sheet to which the developer has been thermally fixed. ### Claim 29 (depends on 25) An image forming apparatus comprising: a main body; an image forming unit accommodated in the main body and configured to transfer a developer image onto a sheet; the fixing apparatus according to claim 25 accommodated in the main body; a top cover disposed on the top of the main body and configured to move between an open position in which the main body is exposed and a closed position in which the main body is covered. ### Claim 30 (depends on 29) The image forming apparatus according to claim 29, wherein the top cover has a contact portion configured to contact the cover part when the top cover is disposed in the closed position, the contact portion extending in a widthwise direction orthogonal to a conveying direction of a sheet. ### Claim 31 (depends on 29) The image forming apparatus according to claim 29, further comprising a pressure rotary body disposed obliquely above the heating rotary body, the pressure rotary body and the heating rotary body configured to convey the sheet therebetween; wherein the thermistor is disposed on the opposite side of the heating rotary body with respect to the pressure rotary body; wherein the case has a first communication port communicating with an interior and exterior of the case, the first communication port being provided above a horizontal plane passing through a rotational center of the pressure rotary body and downstream of a vertical plane passing through the rotational center of the pressure rotary body in the rotating direction of the pressure rotary body; wherein the top cover has a second communication port communicating with an interior and exterior of the top cover, air discharged outside of the case from the inside of the case via the first communication port being further discharged outside of the top cover via the second communication port. ### Claim 32 (depends on 29) The image forming apparatus according to claim 29, wherein at least a part of the cover part is disposed between the thermistor and the image forming unit.