# US 10,768,574 B1 · 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 10,768,574 B1 - Document ID: US10768574B1 - Status: Granted - Kind: B1 - Application number: 16/569,973 - Filed: 2019-09-13 - Granted: 2020-09-08 - Earliest claimed: 2019-09-13 - Assignees: Toshiba Tec Kabushiki Kaisha - Applicants: Toshiba Tec Kabushiki Kaisha - Inventors: Takashi Ogiwara; Masafumi Yoshida; Kazuyoshi Takeshita; Kazumasa Yasui - Web page: https://patentgrep.com/patent/US10768574B1 ## CPC - G03G 21/206: {Conducting air through the machine, e.g. for cooling, filtering, removing gases like ozone} - G03G 21/1633: {using doors or covers (G03G21/1638 takes precedence)} - G03G: ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY ## Abstract An image forming apparatus includes a developer; a heater below the developer; and a case for covering the heater. The apparatus further includes a first air duct of which an end in a first direction side communicates with the outside and which is formed at an inner side of the case, an end of the case in a second direction side opposite to the first direction side being blocked by a blocking plate; a duct arranged between the developer and the case, a second air duct of which an end on the first direction side communicates with the outside and contacting the case and which is formed at an inner side of the duct; a fan, arranged on the second direction side of both the first and second air ducts, configured to blow out air in the first direction side; a cover; and a guide. ## Claims ### Claim 1 An image forming apparatus comprising: a first cover comprising a first opening and a second opening configured to facilitate passage of air through the image forming apparatus; a developer; a heater arranged below the developer; a case configured to cover the heater and having a first end proximate the first opening and a second end opposite the first end, the case comprising: a first air duct configured to facilitate passage of air through the first end and the first opening; and a blocking plate configured to at least partially block passage of air through the second end; a second air duct arranged between the developer and the case, which is in contact with the case and configured to facilitate passage of air through the second opening; a fan located proximate the second end and configured to propel air towards the first end; a second cover configured to cover a portion of the first air duct, a portion of the second air duct, and the fan; and a guide configured to direct air propelled by the fan to the first air duct. ### Claim 2 (depends on 1) The image forming apparatus of claim 1, wherein: the guide comprises a shielding portion arranged between the fan and the second air duct, the shielding portion covering a portion of the fan proximate the second end; and the blocking plate comprises a first ventilating hole proximate the shielding portion. ### Claim 3 (depends on 2) The image forming apparatus of claim 2, wherein: the blocking plate comprises an inclined plate that is inclined downward towards the first air duct; and the first ventilating hole is formed in the inclined plate. ### Claim 4 (depends on 3) The image forming apparatus of claim 3, wherein the shielding portion comprises: a main plate coupled to the inclined plate; a first side plate coupled to the main plate and extending towards the fan; and a second side plate coupled to the main plate opposite the first side plate and extending towards the fan. ### Claim 5 (depends on 1) The image forming apparatus of claim 1, wherein the second cover comprises: a side plate extending along the case towards the first cover; a curved plate coupled to the side plate; and a back plate coupled to the side plate and extending along the fan. ### Claim 6 (depends on 1) The image forming apparatus of claim 1, wherein the heater comprises a power supply. ### Claim 7 (depends on 6) The image forming apparatus of claim 6, wherein: the power supply comprises a primary side circuit and a secondary side circuit; the image forming apparatus is defined by a first direction between the first end and the second end and a width direction that is orthogonal to the first direction; and a center of the fan is arranged closer to the primary side circuit than to the secondary side circuit in the width direction. ### Claim 8 (depends on 1) The image forming apparatus of claim 1, wherein the first air duct and the second air duct are arranged below a plurality of developers. ### Claim 9 (depends on 1) The image forming apparatus of claim 1, wherein: the image forming apparatus is defined by a first direction between the first end and the second end and a vertical direction that is orthogonal to the first direction; and the second air duct is defined by a height measured along the vertical direction; and the height decreases along the first direction from the first end to the second end. ### Claim 10 An image forming apparatus comprising: a first cover comprising a first opening and a second opening configured to facilitate passage of air through the image forming apparatus; a case covered by the first cover, the case having a first end in contact with the first cover proximate the first opening and a second end opposite the first end, the case comprising a first air duct in contact with the first end and configured to facilitate passage of air to the first opening; a second air duct positioned within the first cover and external to the case, the second air duct configured to facilitate passage of air from the second opening towards the second end; at least one developer that is external to the second air duct and the case, and at least partially separated from the case by the second air duct; and a power supply located within the case and separated from the at least one developer by the case and the second air duct. ### Claim 11 (depends on 10) The image forming apparatus of claim 10, further comprising a fan positioned within the first cover and external to the case, the fan located proximate the second end and configured to propel air into the case towards the first end and across the power supply. ### Claim 12 (depends on 11) The image forming apparatus of claim 11, wherein: the power supply comprises a primary side circuit and a secondary side circuit; the primary side circuit is larger than the secondary side circuit; the primary side circuit is configured to be coupled to a commercial power supply; the secondary side circuit is not configured to be coupled to a commercial power supply; the image forming apparatus is defined by a first direction between the first end and the second end and a width direction that is orthogonal to the first direction; and a center of the fan is arranged closer to the primary side circuit than to the secondary side circuit in the width direction. ### Claim 13 (depends on 11) The image forming apparatus of claim 11, wherein the case comprises a blocking plate located at the second end, the blocking plate comprising an opening configured to facilitate passage of air from outside of the case into the case, the opening aligned with the fan. ### Claim 14 (depends on 13) The image forming apparatus of claim 13, further comprising a guide configured to guide air propelled by the fan to the first air duct, the guide comprising a shielding portion arranged between the fan and the second air duct, the shielding portion covering a portion of the fan proximate the second end. ### Claim 15 (depends on 14) The image forming apparatus of claim 14, wherein the blocking plate comprises a first ventilating hole proximate the shielding portion. ### Claim 16 (depends on 15) The image forming apparatus of claim 15, wherein: the blocking plate further comprises an inclined plate that is inclined downward towards the first air duct; and the first ventilating hole is formed in the inclined plate. ### Claim 17 (depends on 16) The image forming apparatus of claim 16, wherein the shielding portion comprises: a main plate coupled to the inclined plate; a first side plate coupled to the main plate and extending towards the fan; and a second side plate coupled to the main plate opposite the first side plate and extending towards the fan. ### Claim 18 An image forming apparatus comprising: a first cover comprising a first opening and a second opening configured to facilitate passage of air through the image forming apparatus; a case positioned within the first cover, the case having a first end in contact with the first cover proximate the first opening and a second end opposite the first end, the case comprising: a first air duct in contact with the first end and configured to facilitate passage of air to the first opening; and a second air duct positioned within the first cover and external to the case, the second air duct configured to facilitate passage of air from the second opening towards the second end; a developer that is external to the second air duct and the case, and at least partially separated from the case by the second air duct; and a fan positioned within the first cover and external to the case, the fan located proximate the second end and configured to propel air into the case towards the first end. ### Claim 19 (depends on 18) The image forming apparatus of claim 18, wherein the case comprises a blocking plate located at the second end, the blocking plate comprising an opening configured to facilitate passage of air from outside of the case into the case, the opening aligned with the fan. ### Claim 20 (depends on 19) The image forming apparatus of claim 19, further comprising a guide configured to guide air propelled by the fan to the first air duct, the guide comprising a shielding portion arranged between the fan and the second air duct, the shielding portion covering a portion of the fan proximate the second end; wherein the blocking plate comprises a first ventilating hole proximate the shielding portion; wherein the blocking plate further comprises an inclined plate that is inclined downward towards the first air duct; wherein the first ventilating hole is formed in the inclined plate; and wherein the shielding portion comprises: a main plate coupled to the inclined plate; a first side plate coupled to the main plate and extending towards the fan; and a second side plate coupled to the main plate opposite the first side plate and extending towards the fan.