# US 12,601,988 B2 · 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 12,601,988 B2 - Document ID: US12601988B2 - Status: Granted - Kind: B2 - Application number: 18/785,412 - Filed: 2024-07-26 - Published: 2025-02-06 - Granted: 2026-04-14 - Earliest claimed: 2023-07-31 - Assignees: KYOCERA Document Solutions Inc. - Applicants: KYOCERA Document Solutions Inc. - Inventors: Ryotaro Todokoro - Web page: https://patentgrep.com/patent/US12601988B2 ## CPC - G03G 15/0435: {by introducing an optical element in the optical path, e.g. a filter} - B41J 2/442: {using lasers} - B41J 2/471: {using dot sequential main scanning by means of a light deflector, e.g. a rotating polygonal mirror} - G02B 26/121: {Mechanical drive devices for polygonal mirrors} - G03G 15/04036: {Details of illuminating systems, e.g. lamps, reflectors (lamp housings for copying cameras, reflex exposure lighting G03B27/542)} - G03G 15/043: with means for controlling illumination or exposure (G03G15/041 takes precedence) - G03G 15/065: {Arrangements for controlling the potential of the developing electrode} - G03G 15/50: {Machine control of apparatus for electrographic processes using a charge pattern, e.g. regulating differents parts of the machine, multimode copiers, microprocessor control (sequencing control G03G21/14)} - G03G 15/80: {Details relating to power supplies, circuits boards, electrical connections} - G03G 21/20: Humidity or temperature control {also ozone evacuation; Internal apparatus environment control} - G03G: ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY - B41J: TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS - G02B: OPTICAL ELEMENTS, SYSTEMS OR APPARATUS ## Abstract An optical scanning device includes a light source unit, a polygonal mirror, a scanning lens, a casing, and a temperature sensor. The light source unit is configured to emit a laser beam. The polygonal mirror is configured to reflect the emitted laser beam from the light source unit by being rotated about a rotation axis extending in an upper-and-lower direction, whereby a peripheral surface of an image bearing member is scanned in a main scanning direction. The scanning lens is configured to form the laser beam reflected by the polygonal mirror into an image on the peripheral surface of the image bearing member. The casing is configured to house the light source unit, the polygonal mirror, and the scanning lens. The temperature sensor is configured to detect a temperature in the casing. The temperature sensor is configured to detect a temperature of the developing device. ## Claims ### Claim 1 An image forming apparatus, comprising: an optical scanning device including a light source unit that is configured to emit a laser beam, a polygonal mirror that is configured to reflect the emitted laser beam from the light source unit by being rotated about a rotation axis extending in an upper-and-lower direction, whereby a peripheral surface of an image bearing member is scanned in a main scanning direction, a scanning lens that is configured to form the laser beam reflected by the polygonal mirror into an image on the peripheral surface of the image bearing member, a casing that is configured to house the light source unit, the polygonal mirror, and the scanning lens, and the image bearing member that includes an at least one image bearing member having a surface on which a photosensitive layer is formed; a charging device that is configured to charge the image bearing member with a predetermined surface potential; a developing device that is arranged to face the image bearing member, that includes a developer carrying member which is configured to carry a developer, and that is configured to form a toner image by applying predetermined developing voltage to the developer carrying member to cause a toner to adhere to an electrostatic latent image formed on the image bearing member; a control unit that is configured to control the optical scanning device, and the developing device; an IC driver that is configured to control the light source unit; a circuit board to which the IC driver is mounted and which is housed in the casing; and a temperature sensor that is mounted to the circuit board wherein, on the circuit board, the temperature sensor is arranged on a side that is opposite to a side where the IC driver is present with an external connection terminal interposed between the temperature sensor and the IC driver, and wherein the control unit controls the developing device on a basis of a temperature detected by the temperature sensor. ### Claim 2 (depends on 1) The image forming apparatus according to claim 1, wherein the control unit controls the optical scanning device on a basis of the temperature in the casing detected by the temperature sensor. ### Claim 3 (depends on 1) The image forming apparatus according to claim 1, wherein the casing has an opening portion that is opened to face the developing device, and wherein, in the casing, the temperature sensor is arranged to face the opening portion. ### Claim 4 (depends on 1) The image forming apparatus according to claim 1, wherein the optical scanning device is arranged adjacently on an upper side relative to the developing device, and further includes a duct that is arranged between the optical scanning device and the developing device, and that is configured to channel heat of the developing device to a side where the temperature sensor is present. ### Claim 5 (depends on 4) The image forming apparatus according to claim 4, wherein an internal flow path of the duct is narrowed toward the temperature sensor. ### Claim 6 (depends on 5) The image forming apparatus according to claim 5, wherein the control unit controls magnitude of the predetermined developing voltage on the basis of the temperature of the developing device, the temperature of the developing device being detected by the temperature sensor. ### Claim 7 (depends on 6) The image forming apparatus according to claim 6, wherein the control unit stops driving the developing device once the temperature of the developing device, the temperature of the developing device being detected by the temperature sensor, has exceeded a predetermined threshold. ### Claim 8 An image forming apparatus, comprising: an optical scanning device including a light source unit that is configured to emit a laser beam, a polygonal mirror that is configured to reflect the emitted laser beam from the light source unit by being rotated about a rotation axis extending in an upper-and-lower direction, whereby a peripheral surface of an image bearing member is scanned in a main scanning direction, a scanning lens that is configured to form the laser beam reflected by the polygonal mirror into an image on the peripheral surface of the image bearing member, a casing that is configured to house the light source unit, the polygonal mirror, and the scanning lens, and a temperature sensor that is configured to detect a temperature in the casing; the image bearing member that includes an at least one image bearing member having a surface on which a photosensitive layer is formed; a charging device that is configured to charge the image bearing member with a predetermined surface potential; a developing device that is arranged to face the image bearing member, that includes a developer carrying member which is configured to carry a developer, and that is configured to form a toner image by applying predetermined developing voltage to the developer carrying member to cause a toner to adhere to an electrostatic latent image formed on the image bearing member; and a control unit that is configured to control the optical scanning device, and the developing device, the temperature sensor detecting a temperature of the developing device, the control unit controlling the optical scanning device on a basis of the temperature in the casing, the temperature in the casing being detected by the temperature sensor, and controlling the developing device on a basis of the temperature of the developing device, the temperature of the developing device being detected by the temperature sensor, the image forming apparatus further comprising: an IC driver that is configured to control the light source unit; and a circuit board to which the IC driver is mounted and which is housed in the casing, wherein the temperature sensor is mounted to the circuit board, and wherein, on the circuit board, the temperature sensor is arranged on a side that is opposite to a side where the IC driver is present with an external connection terminal interposed between the temperature sensor and the IC driver. ### Claim 9 (depends on 8) The image forming apparatus according to claim 8, wherein the casing has an opening portion that is opened to face the developing device, and wherein, in the casing, the temperature sensor is arranged to face the opening portion. ### Claim 10 (depends on 8) The image forming apparatus according to claim 8, wherein the optical scanning device is arranged adjacently on an upper side relative to the developing device, and further includes a duct that is arranged between the optical scanning device and the developing device, and that is configured to channel heat of the developing device to a side where the temperature sensor is present. ### Claim 11 (depends on 10) The image forming apparatus according to claim 10, wherein an internal flow path of the duct is narrowed toward the temperature sensor. ### Claim 12 (depends on 11) The image forming apparatus according to claim 11, wherein the control unit controls magnitude of the predetermined developing voltage on the basis of the temperature of the developing device, the temperature of the developing device being detected by the temperature sensor. ### Claim 13 (depends on 12) The image forming apparatus according to claim 12, wherein the control unit stops driving the developing device once the temperature of the developing device, the temperature of the developing device being detected by the temperature sensor, has exceeded a predetermined threshold.