Abstract: A transfer device includes a transfer drum that rotates in conjunction with a fixing roller, a transfer belt that transfers an image onto a medium while rotating along with the transfer drum in a state where the medium is nipped between the transfer belt and the transfer drum, a pressing member that is disposed in a space enclosed by the transfer belt, and a switching unit that moves the pressing member and switches between a pressed state in which the transfer belt is pressed against the transfer drum and a separated state in which the transfer belt is separated from the transfer drum.

Abstract: A cylinder member includes: a cylinder body having a cross section and including a dent portion; a sheet member wrapped around the cylinder body and including a metal layer contacting the cylinder body and an outer layer; a first attachment member on a sheet member first end portion and removably attached to the dent portion; a second attachment member on a metal layer end portion protruding from the outer layer in the circumferential direction at a sheet member second end portion, the second attachment member being removably attached to the dent portion; a tension-applying mechanism pulling the second attachment member in a dent portion depth direction to apply tension to the metal layer; a projection on one of the second attachment member and metal layer end portion; and a fitting portion on other one of the second attachment member and the metal layer end portion and fitted to the projection.

Abstract: A method for attaching a sheet member to a cylinder body includes: preliminarily fixing a first end portion of the sheet member to a first fixation portion of a cylinder body provided in an apparatus body and having a substantially circular cross section; wrapping the sheet member around the cylinder body by rotating the cylinder body; fixing the first end portion and a second end portion of the sheet member to the first fixation portion and a second fixation portion, respectively; and installing an installation member between the apparatus body and an inner surface of the sheet member before the wrapping of the sheet member around the cylinder body.

Abstract: A drum member includes: a substantially cylindrical drum body having a hollow part extending in an axial direction; a sheet member wound on the drum body; an adjusting mechanism configured to adjust tension in the sheet member, the adjusting mechanism including a moving member that holds an end of the sheet member in a circumferential direction and moves in a depth direction of the hollow part, and a fixing member that fixes the moving member to the drum body; and one or more positioning members that position the moving member such that the moving member does not move in the circumferential direction of the drum body when the moving member is fixed with the fixing member.

Abstract: An image forming apparatus includes: a holding body configured to hold a formed image; a conveyance unit configured to convey a recording medium with a leading end of the recording medium gripped by a gripping portion; and a transfer body including a recessed portion that accommodates the gripping portion and is provided along a direction substantially orthogonal to a rotational direction, configured to sandwich the recording medium conveyed by the conveyance unit between the transfer body and the holding body to transfer an image on the holding body to the recording medium conveyed by the conveyance unit, and including a slope surface provided at a leading end of a portion of an outer circumference not including a portion where the recessed portion is provided, the leading end being on a front end side in the rotational direction, a distance from the slope surface to a rotational center becoming larger toward a downstream side in the rotational direction.

Abstract: A transfer device includes: a transfer drum that has a groove-like recess extending in an axial direction in an outer circumferential portion thereof, rotates about an axis thereof, and comes into contact with a medium being transported at a portion thereof on an upstream side of the recess in a rotation direction; a nip member, the nip member and the transfer drum forming therebetween a nip part where the medium is nipped; an application member that applies a voltage to the nip part where the medium is nipped, so that an image is transferred to the medium; and a contact mechanism that causes the nip member to come into contact only with a portion on the upstream side of the recess in the transfer drum in the rotation direction at a transfer-start time when the transfer of the image to the medium starts.

Abstract: A transfer device includes a transfer drum that rotates in conjunction with a fixing roller, a transfer belt that transfers an image onto a medium while rotating along with the transfer drum in a state where the medium is nipped between the transfer belt and the transfer drum, a pressing member that is disposed in a space enclosed by the transfer belt, and a switching unit that moves the pressing member and switches between a pressed state in which the transfer belt is pressed against the transfer drum and a separated state in which the transfer belt is separated from the transfer drum.

Abstract: A method for attaching a sheet member to a cylinder body includes: preliminarily fixing a first end portion of the sheet member to a first fixation portion of a cylinder body provided in an apparatus body and having a substantially circular cross section; wrapping the sheet member around the cylinder body by rotating the cylinder body; fixing the first end portion and a second end portion of the sheet member to the first fixation portion and a second fixation portion, respectively; and installing an installation member between the apparatus body and an inner surface of the sheet member before the wrapping of the sheet member around the cylinder body.

Abstract: A cylinder member includes: a cylinder body having a cross section and including a dent portion; a sheet member wrapped around the cylinder body and including a metal layer contacting the cylinder body and an outer layer; a first attachment member on a sheet member first end portion and removably attached to the dent portion; a second attachment member on a metal layer end portion protruding from the outer layer in the circumferential direction at a sheet member second end portion, the second attachment member being removably attached to the dent portion; a tension-applying mechanism pulling the second attachment member in a dent portion depth direction to apply tension to the metal layer; a projection on one of the second attachment member and metal layer end portion; and a fitting portion on other one of the second attachment member and the metal layer end portion and fitted to the projection.

Abstract: A transfer device includes: a transfer drum that has a groove-like recess extending in an axial direction in an outer circumferential portion thereof, rotates about an axis thereof, and comes into contact with a medium being transported at a portion thereof on an upstream side of the recess in a rotation direction; a nip member, the nip member and the transfer drum forming therebetween a nip part where the medium is nipped; an application member that applies a voltage to the nip part where the medium is nipped, so that an image is transferred to the medium; and a contact mechanism that causes the nip member to come into contact only with a portion on the upstream side of the recess in the transfer drum in the rotation direction at a transfer-start time when the transfer of the image to the medium starts.

Abstract: A cylinder member includes: a cylinder body having a cylindrical shape; a sheet member wound on the cylinder body; a first attachment portion provided at one end portion of the sheet member in a circumferential direction, the first attachment portion being detachably attached to the cylinder body; and a second attachment portion provided at the other end portion of the sheet member in the circumferential direction, the second attachment portion being detachably attached to the cylinder body.

Abstract: A drum member includes: a substantially cylindrical drum body having a hollow part extending in an axial direction; a sheet member wound on the drum body; an adjusting mechanism configured to adjust tension in the sheet member, the adjusting mechanism including a moving member that holds an end of the sheet member in a circumferential direction and moves in a depth direction of the hollow part, and a fixing member that fixes the moving member to the drum body; and one or more positioning members that position the moving member such that the moving member does not move in the circumferential direction of the drum body when the moving member is fixed with the fixing member.

Abstract: A transfer device includes: a transfer member to which a voltage is applied by a power supply device to generate a transfer electric field for transferring a developer image to a recording medium; a transfer cylinder having a recess in which a retaining member that retains a leading end portion of the recording medium is disposed, the transfer electric field being generated between the transfer cylinder and the transfer member at a transfer position; a shunt circuit by which the voltage applied to the transfer member is shunted to a reference potential point; and an operation stopping mechanism that starts and stops an operation of the shunt circuit in response to rotation of the transfer cylinder, the operation being started when the recess reaches the transfer position and stopped when the recess leaves the transfer position.

Abstract: A transfer device includes: a transfer member to which a voltage is applied by a power supply device to generate a transfer electric field for transferring a developer image to a recording medium; a transfer cylinder having a recess in which a retaining member that retains a leading end portion of the recording medium is disposed, the transfer electric field being generated between the transfer cylinder and the transfer member at a transfer position; a shunt circuit by which the voltage applied to the transfer member is shunted to a reference potential point; and an operation stopping mechanism that starts and stops an operation of the shunt circuit in response to rotation of the transfer cylinder, the operation being started when the recess reaches the transfer position and stopped when the recess leaves the transfer position.

Abstract: An image forming apparatus includes: a rotating body having a recess in an outer peripheral surface thereof; a transfer portion that is in contact with the outer peripheral surface of the rotating body, the transfer portion being configured to transfer a toner to a recording medium passing between the rotating body and the transfer portion; and a brush configured to come into contact with the outer peripheral surface of the rotating body to remove a toner adhering to the outer peripheral surface.

Abstract: A method for manufacturing a cylindrical member includes: fixing an end portion of an elastic body to an end portion, in a circumferential direction, of a recess provided in a cylindrical body having a substantially circular shape in cross section, the recess extending along an axial direction of the cylindrical body; and winding the elastic body around the cylindrical body while pressing the elastic body using a pressing member.

Abstract: A method for manufacturing an elastic body having a two-layer structure includes: forming a first elastic body on a provisional cylinder body having a substantially circular shape in cross section; and forming a second elastic body integrally with the first elastic body, which has been formed on the provisional cylinder body.

Abstract: A cylinder member includes: a cylinder body having a cylindrical shape; a sheet member wound on the cylinder body; a first attachment portion provided at one end portion of the sheet member in a circumferential direction, the first attachment portion being detachably attached to the cylinder body; and a second attachment portion provided at the other end portion of the sheet member in the circumferential direction, the second attachment portion being detachably attached to the cylinder body.

Abstract: An image forming apparatus includes: multiple image forming units that form toner images; an intermediate transfer belt that rotates so as to pass through the image forming units; multiple first-transfer rollers that are provided in a manner capable of being displaced between transfer positions, where the first-transfer rollers make the intermediate transfer belt come into contact with the image forming units, and retracted positions, where the first-transfer rollers make the intermediate transfer belt be separated from the image forming units, and that first-transfer the toner images to the intermediate transfer belt when the first-transfer rollers are located at the transfer positions; a displacement mechanism including a moving unit that comes into contact with and moves a first-transfer roller that is not involved in transfer in a first mode, in which an image is formed with one image forming unit, among the first-transfer rollers of the image forming units, so as to be displace the first transfer roller

Abstract: Ringing of a signal after passing through a low pass filter in an LINC type linear amplifier is remedied. A linear amplifying device includes the linear amplifier including the low pass filter for removing high-frequency components; and an origin avoiding circuit which receives an original input signal and is provided upstream of the linear amplifier. If the original input signal is sampled in the vicinity of an origin, the origin avoiding circuit modifies a sampled value so at to replace the sampled value with a fixed value, and supplies the modified input signal to the linear amplifier.