# US 2017/0255147 A1 · Fixing device and image forming apparatus incorporating same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2017/0255147 A1 - Document ID: US20170255147A1 - Status: Published application - Kind: A1 - Application number: 15/440,179 - Filed: 2017-02-23 - Published: 2017-09-07 - Earliest claimed: 2016-03-03 - Assignees: Ricoh Company, Ltd. - Inventors: Takayuki SEKI; Kenji ISHll; Hiroshi YOSHINAGA; Takashi SETO; lppei FUJIMOTO; Kazunari SAWADA; Ryohei MATSUDA - Web page: https://patentgrep.com/patent/US20170255147A1 ## CPC - G03G 15/2053: {Structural details of heat elements, e.g. structure of roller or belt, eddy current, induction heating} - G03G 15/2039: {with means for controlling the fixing temperature} - G03G 15/2042: {specially for the axial heat partition} - G03G 15/2046: {specially for the influence of heat loss, e.g. due to the contact with the copy material or other roller} - G03G 15/2057: {relating to the chemical composition of the heat element and layers thereof} - G03G 2215/0132: vertical medium transport path at the secondary transfer - G03G 2215/2035: the fixing nip having a stationary belt support member opposing a pressure member - G03G: ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY ## Abstract A fixing device includes a fixing rotator, an opposed rotator disposed opposite the fixing rotator, a pressure pad, a lateral end heater, and a thermal conduction aid. The pressure pad presses against the opposed rotator via the fixing rotator to form a fixing nip between the fixing rotator and the opposed rotator. The lateral end heater is disposed on the pressure pad to heat a lateral end of the fixing rotator in the axial direction of the fixing rotator. The thermal conduction aid is interposed between the pressure pad and the fixing rotator to decrease a temperature gradient of the fixing rotator in an axial direction of the fixing rotator. The pressure pad includes a nip-side face disposed opposite the thermal conduction aid. The lateral end heater includes a nip-side face being disposed opposite the thermal conduction aid and projecting beyond the nip-side face of the pressure pad. ## Claims ### Claim 1 A fixing device comprising: an endless fixing rotator, formed into a loop and rotatable in a direction of rotation; an opposed rotator disposed opposite an outer circumferential surface of the fixing rotator; a pressure pad disposed opposite an inner circumferential surface of the fixing rotator to press against the opposed rotator via the fixing rotator to form a fixing nip between the fixing rotator and the opposed rotator, a lateral end heater disposed on the pressure pad to heat a lateral end of the fixing rotator in the axial direction of the fixing rotator; and a thermal conduction aid interposed between the pressure pad and the fixing rotator to decrease a temperature gradient of the fixing rotator in an axial direction of the fixing rotator, the pressure pad including a nip-side face disposed opposite the thermal conduction aid, the lateral end heater including a nip-side face being disposed opposite the thermal conduction aid and projecting beyond the nip-side face of the pressure pad. ### Claim 2 (depends on 1) The fixing device according to claim 1, wherein sue thermal conduction aid includes a pad-side face disposed opposite the pressure pad, and wherein the nip-side lace of the pressure pad is spaced apart from the pad-side of the thermal conduction aid. ### Claim 3 (depends on 1) The fixing device according to claim 1, wherein the thermal conduction aid includes a pad-side face disposed opposite the pressure pad, and wherein the nip-side face of the pressure pad has a shape that conforms to a shape of the pad-side lace of the thermal conduction aid. ### Claim 4 (depends on 1) The fixing device according to claim 1, wherein the nip-side face of the pressure pad includes a center face and an end face in the axial direction of the fixing rotator, and wherein the center face projects beyond the end face. ### Claim 5 (depends on 1) The fixing device according to claim 1, further comprising an interposer interposed between the thermal conduction aid and the lateral end heater to conduct heat from the lateral end heater to the thermal conduction aid, wherein the interposer has a shape that conforms to a shape of the thermal conduction aid and a shape of the lateral end heater. ### Claim 6 (depends on 1) The fixing device according to claim 1, further comprising: a first heater disposed opposite the inner circumferential surface of the fixing rotator to heat the fixing rotator, the first heater including a first heat generator; and a second heater disposed opposite the inner circumferential surface of the fixing rotator to heat the fixing rotator, the second heater including a second heat generator different from the first heat generator in location in the axial direction of the fixing rotator. ### Claim 7 (depends on 6) The fixing device according to claim 6, wherein the second heat generator of the second heater is disposed outboard from the first heat generator of the first heater in the axial direction of the fixing rotator. ### Claim 8 (depends on 7) The fixing device according to claim 7, wherein the lateral end beater further includes: a first heat generation span in the axial direction of the fixing rotator; and a second heat generation span in a direction perpendicular to the axial direction of the fixing rotator, and wherein apart of the first heat generation span of the lateral end heater overlaps the second heat generator of the second heater in the axial direction of the fixing rotator. ### Claim 9 (depends on 1) The fixing device according to claim 1, wherein the lateral end heater further includes: a first, heat generation span in the axial direction of the fixing rotator; and a second heat generation span in a direction perpendicular to the axial direction of the fixing rotator, and wherein the second heat generation span of the lateral end heater is smaller than a width of the thermal conduction aid in the direction perpendicular to the axial direction of the fixing rotator. ### Claim 10 (depends on 1) The fixing device according to claim 1, wherein the thermal conduction aid contacts the lateral end heater. ### Claim 11 (depends on 1) The fixing device according to claim 1, wherein the lateral end heater further includes a resistive heat generator. ### Claim 12 (depends on 11) The fixing device according to claim 11, wherein the resistive heat generator is U-shaped. ### Claim 13 (depends on 11) The fixing device according to claim 11, wherein the resistive heat generator has a serpentine shape. ### Claim 14 (depends on 1) An image forming apparatus comprising: an image forming device to form a toner image: and the fixing device according to claim 1, the fixing device being disposed downstream from the image forming device in a direction of recording medium conveyance to fix the toner image on a recording medium.