# US 11,079,711 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 11,079,711 B2 - Document ID: US11079711B2 - Status: Granted - Kind: B2 - Application number: 16/449,957 - Filed: 2019-06-24 - Published: 2019-10-10 - Granted: 2021-08-03 - Earliest claimed: 2016-12-27 - Assignees: Hewlett-Packard Development Company, L.P. - Applicants: Hewlett-Packard Development Company, L.P. - Inventors: Koji Miyake; Satoru Furuya; Kensuke Nakajima; Shun Ikeura - Web page: https://patentgrep.com/patent/US11079711B2 ## CPC - G03G 21/0035: {using a brush; Details of cleaning brushes, e.g. fibre density (G03G21/0064 takes precedence; magnetic brushes G03G21/0047)} - A46B 5/00: Brush bodies; Handles integral with brushware - B41F 35/04: for inking rollers - G03G 15/00: Apparatus for electrographic processes using a charge pattern (G03G16/00, G03G17/00 take precedence) - G03G 15/16: of a toner pattern, e.g. a powder pattern {, e.g. magnetic transfer} - G03G 15/161: {with means for handling the intermediate support, e.g. heating, cleaning, coating with a transfer agent} - G03G 15/1675: {with means for controlling the bias applied in the transfer nip} - G03G 15/168: {with means for conditioning the transfer element, e.g. cleaning} - G03G 21/00: Arrangements not provided for by groups G03G13/00 - G03G19/00, e.g. cleaning, elimination of residual charge - G03G 21/007: {Arrangement or disposition of parts of the cleaning unit} - B41F 16/00: Transfer printing apparatus - G03G 2215/1647: Cleaning of transfer member - G03G 2221/0005: Cleaning of residual toner - G03G 2221/1627: Details concerning the cleaning process - G03G: ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY - A46B: BRUSHES (handles not integral with brushware B25G) - B41F: PRINTING MACHINES OR PRESSES (manifolding devices or office printing machines B41L) ## Abstract An image forming apparatus includes a rotatable cylindrical component to be cleaned, and a bar brush having a base substrate and bristles. The base substrate of the bar brush is located at a fixed position relative to the component to be cleaned. The bristles extend from the base substrate to contact the component to be cleaned. The bristles have free ends that form a tip end surface of the bar brush. The tip end surface has a curved shape that conforms with a surface of the component, when the bristles are not in contact with the surface to be cleaned. ## Claims ### Claim 1 An image forming apparatus comprising: a transfer roller; an image carrier to carry a plurality of adjusting toner images spaced apart along an axial direction of the image carrier and to form a transfer nip region between the image carrier and the transfer roller; and a bar brush comprising a base substrate located at a fixed position relative to the transfer roller, and bristles extending from the base substrate to contact the transfer roller, wherein the bristles have free ends that form a tip end surface of the bar brush, wherein the tip end surface has a curved shape that conforms with a surface of the transfer roller when the bristles are not in contact with the transfer roller, and wherein the bar brush is disposed discontinuously along an axial direction of the transfer roller in alignment with the plurality of adjusting toner images. ### Claim 2 (depends on 1) The image forming apparatus according to claim 1, wherein the bristles are provided substantially vertically in the base substrate, and wherein the base substrate is bent to the curved shape that conforms with the surface of the transfer roller. ### Claim 3 (depends on 2) The image forming apparatus according to claim 2, wherein a bite amount of the bristles with respect to the transfer roller is larger at an upstream side than at a downstream side of the transfer roller. ### Claim 4 (depends on 1) The image forming apparatus according to claim 1, wherein the bar brush is aligned with a position along the axial direction of the transfer roller, where an adjusting toner image is to pass through the transfer nip region during an image adjustment operation. ### Claim 5 (depends on 4) The image forming apparatus according to claim 4, wherein the transfer roller comprises a cylindrical metal core and a cylindrical foam layer disposed around the cylindrical metal core, wherein in a cross section of the foam layer, a diameter of cells in the foam layer is 500 μm or less, and wherein a static coefficient of friction of the foam layer to the image carrier is approximately 10.6 or less at a temperature of approximately 30° C. and a humidity of approximately 85%. ### Claim 6 (depends on 4) The image forming apparatus according to claim 4, wherein the image carrier includes a photosensitive body, and wherein the image forming apparatus comprises a bias application device to apply a transfer bias to the transfer roller, to transfer a toner image formed on the photosensitive body to a transfer material that passes through the transfer nip region. ### Claim 7 (depends on 4) The image forming apparatus according to claim 4, further comprising: a plurality of photosensitive bodies to primarily transfer successive toner images to the image carrier; a transfer device including the transfer nip region between the transfer device and the image carrier, the transfer nip region to convey a transfer material to secondarily transfer the toner images primarily transferred on the image carrier onto the transfer material, wherein the transfer device includes a support roller and the transfer roller to hold the image carrier between the support roller and the transfer roller, wherein the support roller is disposed on a side of the image carrier to which the toner images are not transferred, and the transfer roller is disposed on a side of the image carrier to which the toner images are transferred; and a bias application device to apply a transfer bias to the support roller or the transfer roller of the transfer device to transfer the toner images to the transfer material. ### Claim 8 (depends on 7) The image forming apparatus according to claim 7, wherein, in a normal mode, the toner images are formed on the image carrier, the toner images are transferred to the transfer material, and a normal-mode polarity is applied to the transfer roller, and wherein, in an image adjustment mode, an image adjustment is performed on the image carrier based on the plurality of adjusting toner images carried on the image carrier and the bias application device is to apply, to the transfer roller, a reverse bias of a polarity opposite to the normal-mode polarity. ### Claim 9 (depends on 7) The image forming apparatus according to claim 7, wherein, in a cleaning mode, the bias application device alternately applies positive and negative biases to the transfer roller. ### Claim 10 An image forming apparatus comprising: a rotatable cylindrical component to be cleaned; and a bar brush comprising a base substrate located at a fixed position relative to the component to be cleaned and bristles extending from the base substrate to contact the component to be cleaned, wherein the bristles have free ends that form a tip end surface of the bar brush, wherein the tip end surface has a curved shape that conforms with a surface of the component to be cleaned when the bristles are not in contact with the surface to be cleaned, wherein the cylindrical component to be cleaned comprises a cylindrical metal core and a cylindrical foam layer disposed around the cylindrical metal core, wherein, in a cross section of the foam layer, a diameter of cells in the foam layer is 500 μm or less, and wherein a static coefficient of friction of the foam layer to the image carrier is approximately 10.6 or less at a temperature of approximately30° C. and a humidity of approximately 85%. ### Claim 11 (depends on 10) The image forming apparatus of claim 10, wherein the bristles are provided substantially vertically in the base substrate, and wherein the base substrate is bent to the curved shape that conforms with the surface of the component to be cleaned. ### Claim 12 (depends on 10) The image forming apparatus according to claim 10, further comprising an image carrier to carry an adjusting toner image when an image adjustment operation is carried out, wherein the component to be cleaned includes a transfer roller to form a transfer nip region between the transfer roller and the image carrier, and wherein the bar brush is aligned with a position along an axial direction of the transfer roller where the adjusting toner image passes through the transfer nip region when the image adjustment operation is carried out. ### Claim 13 (depends on 12) The image forming apparatus according to claim 12, wherein the image carrier is to carry a plurality of adjusting toner images, including the adjusting toner image, the plurality of adjusting toner images to be spaced apart along the axial direction of the image carrier, and wherein the bar brush is disposed discontinuously along the axial direction of the transfer roller in alignment with the plurality of adjusting toner images. ### Claim 14 (depends on 12) The image forming apparatus according to claim 12, wherein the image carrier includes a photosensitive body, and wherein the image forming apparatus comprises a bias application device to apply a transfer bias to the transfer roller, to transfer a toner image formed on the photosensitive body to a transfer material that passes through the transfer nip region. ### Claim 15 (depends on 12) The image forming apparatus according to claim 12, further comprising: a plurality of photosensitive bodies to primarily transfer successive toner images to the image carrier; a transfer device including the transfer nip region between the transfer device and the image carrier, the transfer nip region to convey a transfer material to secondarily transfer the toner images primarily transferred on the image carrier onto the transfer material, wherein the transfer device includes a support roller and the transfer roller to hold the image carrier between the support roller and the transfer roller, wherein the support roller is disposed on a side of the image carrier to which the toner images are not transferred, and the transfer roller is disposed on a side of the image carrier to which the toner images are transferred; and a bias application device to apply a transfer bias to the support roller or the transfer roller of the transfer device to transfer the toner images to the transfer material. ### Claim 16 (depends on 15) The image forming apparatus according to claim 15, wherein, in a normal mode, the toner images are formed on the image carrier, the toner images are transferred to the transfer material, and a normal-mode polarity is applied to the transfer roller, and wherein, in an image adjustment mode, an image adjustment is performed on the image carrier based on the plurality of adjusting toner images carried on the image carrier and the bias application device is to apply, to the transfer roller, a reverse bias of a polarity opposite to the normal-mode polarity. ### Claim 17 (depends on 15) The image forming apparatus according to claim 15, wherein, in a cleaning mode, the bias application device alternately applies positive and negative biases to the transfer roller. ### Claim 18 (depends on 10) The image forming apparatus according to claim 10, wherein a bite amount of the bristles with respect to the component to be cleaned is larger at an upstream side than at a downstream side of the component to be cleaned.