Abstract: The cleaning member is disposed to be opposite to the first roller with the second roller being provided therebetween. Compared to a case when the second roller is placed at a first position on a side of the first roller, if the second roller is placed at a second position on a side of the cleaning roller, a pressure between the second roller and the first roller becomes smaller, and a pressure between the second roller and the cleaning member becomes larger.

Abstract: To provide a roller device that can improve the life of a cleaning member and that enables a cleaning member to perform a cleaning operation even when a contact-pressure release operation is performed to release the contact-pressure of the second roller on the first roller and to provide a fixing device and an image forming apparatus. The cleaning member is disposed to be opposite to the first roller with the second roller being provided therebetween. Compared to a case when the second roller is placed at a first position on a side of the first roller, if the second roller is placed at a second position on a side of the cleaning roller, a pressure between the second roller and the first roller becomes smaller, and a pressure between the second roller and the cleaning member becomes larger.

Abstract: A fixing portion is provided with a fixing roller, a heating roller having a heat source, a fixing belt stretched between the fixing roller and the heating roller, and a pressurizing roller that is brought into pressure contact with the fixing roller across the fixing belt and forms a nip portion into which a sheet of paper is conveyed between the fixing belt and the pressurizing roller. The fixing portion is further provided with a pad that has a contact surface portion in contact with the inner peripheral surface of the fixing belt, and a biasing member that biases the pad in a direction in which the contact surface portion is brought into pressure contact with the inner peripheral surface of the fixing belt. The pad is configured so as to pivot about the rotating shaft of the heating roller.

Abstract: A fixing portion is provided with a fixing roller, a heating roller having a heat source, a fixing belt stretched between the fixing roller and the heating roller, and a pressurizing roller that is brought into pressure contact with the fixing roller across the fixing belt and forms a nip portion into which a sheet of paper is conveyed between the fixing belt and the pressurizing roller. The fixing portion is further provided with a pad that has a contact surface portion in contact with the inner peripheral surface of the fixing belt, and a biasing member that biases the pad in a direction in which the contact surface portion is brought into pressure contact with the inner peripheral surface of the fixing belt. The pad is configured so as to pivot about the rotating shaft of the heating roller.

Abstract: A fixing device in accordance with the present invention comprises: a rotary member for transporting printing paper; a pressure member for press-contacting the rotary member to apply pressure onto the printing paper; and a cleaning member capable of freely moving into contact with, or away from, a peripheral surface of the rotary member and/or a peripheral surface of the pressure member. A toner image formed on the printing paper is fixed while the printing paper is being held between the rotary member and the pressure member. The fixing device further comprises a contact and separation unit for moving the pressure member into contact with, or away from, the rotary member. The cleaning member moves into contact with, or away from, the peripheral surface of the rotary member and/or the peripheral surface of the pressure member in conjunction with the contact and separation unit moving the pressure member into contact with, or away from, the rotary member.

Abstract: An image forming apparatus includes a pre-fixing sheet guide and a toner collection device. The pre-fixing sheet guide is to let a sheet conveyed along it, the sheet with a toner image transferred thereon at a transfer portion to an end part of the sheet. The sheet guide has a width shorter than a maximum printable sheet width. The toner collection device includes an adsorption member (pressure roller) that is disposed in the vicinity of the pre-fixing sheet guide and having a surface exhibiting conductivity, and a potential difference formation mechanism (earth mechanism) configured to form a potential difference between the surface of the adsorption member and the toner.

Abstract: An image forming apparatus includes a pre-fusing paper sheet guide, a fuser unit and a control section. The pre-fusing paper sheet guide is disposed adjacent to the fuser unit on its upstream side. The fuser unit includes a pressing roller having, an electrically conductive surface, a grounding structure grounding a pressing roller's surface, and a cleaning mechanism cleaning the pressing roller's surface. The cleaning mechanism includes a web and a take-up roller. The control section sets a winding quantity x of the web to 0.7 mm when a setting for printing without margin is not made, and sets the winding quantity x to 2.1 mm when the setting for printing without margin is made. If the number of sheets accumulated through the image forming process becomes not less than 18, the control section causes the take-up roller to wind the web by the winding quantity x, and performs an image forming process.

Abstract: The present invention provides an image forming apparatus in which a recording paper to which a toner has been transferred is guided by a guide member and transported to a nip region between two rotatable members that are pressed against each other, and the toner on the recording paper is fixed at the nip region. In this image forming apparatus, a conductive or semiconductive region and an insulating region that are to be brought into contact with the recording paper are sequentially arranged in a recording paper transport direction on a guide face of the guide member, the conductive or semiconductive region is grounded, and the insulating region includes an end portion of the guide member oriented in the recording paper transport direction.

Abstract: An image forming apparatus includes a pre-fusing paper sheet guide, a fuser unit and a control section. The pre-fusing paper sheet guide is disposed adjacent to the fuser unit on its upstream side. The fuser unit includes a pressing roller having, an electrically conductive surface, a grounding structure grounding a pressing roller's surface, and a cleaning mechanism cleaning the pressing roller's surface. The cleaning mechanism includes a web and a take-up roller. The control section sets a winding quantity x of the web to 0.7 mm when a setting for printing without margin is not made, and sets the winding quantity x to 2.1 mm when the setting for printing without margin is made. If the number of sheets accumulated through the image forming process becomes not less than 18, the control section causes the take-up roller to wind the web by the winding quantity x, and performs an image forming process.

Abstract: An image forming apparatus includes a pre-fixing sheet guide and a toner collection device. The pre-fixing sheet guide is to let a sheet conveyed along it, the sheet with a toner image transferred thereon at a transfer portion to an end part of the sheet. The sheet guide has a width shorter than a maximum printable sheet width. The toner collection device includes an adsorption member (pressure roller) that is disposed in the vicinity of the pre-fixing sheet guide and having a surface exhibiting conductivity, and a potential difference formation mechanism (earth mechanism) configured to form a potential difference between the surface of the adsorption member and the toner.

Abstract: The present invention provides an image forming apparatus in which a recording paper to which a toner has been transferred is guided by a guide member and transported to a nip region between two rotatable members that are pressed against each other, and the toner on the recording paper is fixed at the nip region. In this image forming apparatus, a conductive or semiconductive region and an insulating region that are to be brought into contact with the recording paper are sequentially arranged in a recording paper transport direction on a guide face of the guide member, the conductive or semiconductive region is grounded, and the insulating region includes an end portion of the guide member oriented in the recording paper transport direction.

Abstract: A fixing device in accordance with the present invention comprises: a rotary member for transporting printing paper; a pressure member for press-contacting the rotary member to apply pressure onto the printing paper; and a cleaning member capable of freely moving into contact with, or away from, a peripheral surface of the rotary member and/or a peripheral surface of the pressure member. A toner image formed on the printing paper is fixed while the printing paper is being held between the rotary member and the pressure member. The fixing device further comprises a contact and separation unit for moving the pressure member into contact with, or away from, the rotary member. The cleaning member moves into contact with, or away from, the peripheral surface of the rotary member and/or the peripheral surface of the pressure member in conjunction with the contact and separation unit moving the pressure member into contact with, or away from, the rotary member.

Abstract: A fixing apparatus 12 in one embodiment of the present invention includes a fixing roller 31, a pressure roller 32, a pressing apparatus 100 for pressing the pressure roller 32 toward the fixing roller 31, a pressure cancellation apparatus 200 that cancels pressure applied by the pressing apparatus 100 to the pressure roller 32 against the fixing roller 31, an external heating apparatus 300 that presses the fixing roller 31 from the outside on an opposite side to the pressure roller 32, and a regulation member 400 that regulates the amount of pressure the external heating apparatus 300 applies to the fixing roller 31.

Abstract: The present invention provides an image forming apparatus in which a recording paper to which a toner has been transferred is guided by a guide member and transported to a nip region between two rotatable members that are pressed against each other, and the toner on the recording paper is fixed at the nip region. In this image forming apparatus, a conductive or semiconductive region and an insulating region that are to be brought into contact with the recording paper are sequentially arranged in a recording paper transport direction on a guide face of the guide member, the conductive or semiconductive region is grounded, and the insulating region includes an end portion of the guide member oriented in the recording paper transport direction.

Abstract: In one embodiment, when a hot roller is driven to rotate, a driving gear rotates so that a swing gear and a swing cam rotate. Then, a sliding contact edge on the right side of a swing lever that abuts against the circumferential face of the swing cam repeatedly moves up and down, and the swing lever repeatedly rotates clockwise and counterclockwise with a shaft of a pressure release cam as the center. At this time, since only the clockwise rotation of the swing lever is transmitted via a one-way clutch to the shaft of the pressure release cam, the clockwise rotation is intermittently transmitted to the shaft of the pressure release cam. As a result of this, the pressure release cam intermittently rotates clockwise, and the pressure release cam pushes away a roller of a displacement frame, so that the pressure roller separates from the hot roller.

Abstract: A fusing unit for an image forming apparatus includes a fusing roller and a pressing roller, each having an elastic layer on their outer peripheral surfaces. A pressing structure presses the fusing roller against the pressing roller. When a sheet of paper with an unfixed toner image passes through a nip portion where the fusing roller and pressing roller are in press-contact with each other, the toner image is fused and fixed to the paper. The fusing unit further includes a pressure release lever for regulating the pressing action of the pressing structure when the rollers are put in press-contact with each other.

Abstract: A fixing apparatus 12 in one embodiment of the present invention includes a fixing roller 31, a pressure roller 32, a pressing apparatus 100 for pressing the pressure roller 32 toward the fixing roller 31, a pressure cancellation apparatus 200 that cancels pressure applied by the pressing apparatus 100 to the pressure roller 32 against the fixing roller 31, an external heating apparatus 300 that presses the fixing roller 31 from the outside on an opposite side to the pressure roller 32, and a regulation member 400 that regulates the amount of pressure the external heating apparatus 300 applies to the fixing roller 31.

Abstract: In one embodiment, when a hot roller is driven to rotate, a driving gear rotates so that a swing gear and a swing cam rotate. Then, a sliding contact edge on the right side of a swing lever that abuts against the circumferential face of the swing cam repeatedly moves up and down, and the swing lever repeatedly rotates clockwise and counterclockwise with a shaft of a pressure release cam as the center. At this time, since only the clockwise rotation of the swing lever is transmitted via a one-way clutch to the shaft of the pressure release cam, the clockwise rotation is intermittently transmitted to the shaft of the pressure release cam. As a result of this, the pressure release cam intermittently rotates clockwise, and the pressure release cam pushes away a roller of a displacement frame, so that the pressure roller separates from the hot roller.

Abstract: A fusing unit is comprised of a fusing roller and a pressing roller, having an elastic layer on their outer peripheral surface and a pressing structure for pressing the fusing roller against the pressing roller, and causes a sheet of paper with an unfixed toner image to pass through the nip portion where the fusing roller and pressing roller are put in press-contact with each other so as to fuse the toner image and fix it to the paper. This fusing unit further includes a pressure release lever for regulating the pressing action of the pressing structure when the rollers are put in press-contact with each other by the pressing structure.