A feeding roller structure includes a fastening frame, a transmission component, a transmission roller and a floating coupler. The transmission component is assembled in the fastening frame. The transmission component includes a drive shaft mounted on two sides of the fastening frame. The transmission roller is concentrically arranged around the drive shaft. The floating coupler is mounted to the fastening frame. The floating coupler is coupled between the drive shaft and the transmission roller. Two opposite ends of the floating coupler are adjacent to and spaced from the two sides of the fastening frame to form two gaps. Each gap is formed between one end of the floating coupler and one side of the fastening frame. The two gaps limit an angular displacement of the floating coupler.

A medium conveying apparatus includes an imaging device to image a medium and configured to move in a moving direction, a roller configured to move in the moving direction, on an upstream side of the imaging device, a conveyance guide provided with the imaging device to move the imaging device, wherein the conveyance guide includes a slope for coming into contact with the medium, an engaging member provided with the imaging device to move the imaging device, and a moving member to move the imaging device by engaging with the engaging member in conjunction with a movement of the roller. The engaging member and the moving member are configured to be separated at a distance from one another when the medium is not conveyed. The moving member moves the imaging device by engaging with the engaging member only when the medium has a thickness greater than the distance.

A feeding roller structure includes a fastening frame, a transmission component, a transmission roller and a floating coupler. The transmission component is assembled in the fastening frame. The transmission component includes a drive shaft transversely pivoted to two sides of the fastening frame. The transmission roller is concentrically arranged around the drive shaft. The floating coupler is mounted to the fastening frame. The floating coupler is coupled between the drive shaft and the transmission roller. Two opposite ends of the floating coupler are adjacent to and spaced from the two sides of the fastening frame to form two gaps. Each gap is formed between one end of the floating coupler and one side of the fastening frame. The two gaps limit an angular displacement of the floating coupler.

A sheet conveying device includes a conveying roller configured to convey a sheet and a plurality of driven rotating units. The conveying roller includes a plurality of roller portions disposed at positions opposite to the driven rotating units. Each of the roller portions has three or more annular grooves arranged side by side. Each of the driven rotating units includes three or more driven rotating bodies that are disposed at positions opposite to the annular grooves, respectively. A plurality of convex portions and a plurality of concave portions are alternately provided on an outer edge of each of the driven rotating bodies. The driven rotating bodies include two first rotating bodies positioned at both ends and one or more second rotating bodies located between the first rotating bodies and having an outer diameter smaller than the outer diameter of the first rotating bodies.

Manufacturing decorative panels by using a web-fed inkjet printer. During the feeding of the to-be-printed substrate, the tension of the substrate is controlled by a dancer unit (720) which includes a dancer roll (200), having a connector (120) on both side ends of said roll, and wherein both connectors (120) are connected to a pair of parallel guiders (110) for floating said roll along a floating path (210); and wherein the step of controlling comprises the step of moving one guider (110) of said pair of guiders (110) parallel to said floating path (210) whereby the dancer roll (200) is tilted.

A medium conveying apparatus includes a first roller, a second roller located to face the first roller, to hold and convey a medium with the first roller, a drive shaft to rotate the second roller, a motor to rotate the drive shaft, and a joint to connect the second roller and the drive shaft. The joint is configured to keep connecting the second roller and the drive shaft when the second roller moves in a vertical direction. The drive shaft is located at an intermediate position between a first position where the second roller is in contact with the first roller and a second position where the second roller separates most from the first roller in the vertical direction. A distance between the second position and the intermediate position is greater than a radius on cross section of the second roller in the vertical direction.

A sheet conveying device includes a conveying roller configured to convey a sheet and a plurality of driven rotating units. The conveying roller includes a plurality of roller portions disposed at positions opposite to the driven rotating units. Each of the roller portions has three or more annular grooves arranged side by side. Each of the driven rotating units includes three or more driven rotating bodies that are disposed at positions opposite to the annular grooves, respectively. A plurality of convex portions and a plurality of concave portions are alternately provided on an outer edge of each of the driven rotating bodies. The driven rotating bodies include two first rotating bodies positioned at both ends and one or more second rotating bodies located between the first rotating bodies and having an outer diameter smaller than the outer diameter of the first rotating bodies.

A medium transport apparatus includes a transport roller configured to transport a medium and a roller support portion configured to support the transport roller. The roller support portion includes a support member contacting an outer circumferential surface of the transport roller at two positions thereof in a circumferential direction to support the transport roller, a base member defining a position of the support member, and an intermediary member mediating the support member and the base member. The intermediary member is configured to cause separation between the support member and the base member without moving the support member and the base member.

A medium conveying apparatus includes a first roller, a second roller located to face the first roller, to hold and convey a medium with the first roller, a drive shaft to rotate the second roller, a motor to rotate the drive shaft, and a joint to connect the second roller and the drive shaft. The joint is configured to keep connecting the second roller and the drive shaft when the second roller moves in a vertical direction. The drive shaft is located at an intermediate position between a first position where the second roller is in contact with the first roller and a second position where the second roller separates most from the first roller in the vertical direction. A distance between the second position and the intermediate position is greater than a radius on cross section of the second roller in the vertical direction.

A medium conveying apparatus includes an imaging device to image a medium and configured to move in a moving direction, a roller configured to move in the moving direction, on an upstream side of the imaging device, a conveyance guide provided with the imaging device to move the imaging device, wherein the conveyance guide includes a slope for coming into contact with the medium, an engaging member provided with the imaging device to move the imaging device, and a moving member to move the imaging device by engaging with the engaging member in conjunction with a movement of the roller. The engaging member and the moving member are configured to be separated at a distance from one another when the medium is not conveyed. The moving member moves the imaging device by engaging with the engaging member only when the medium has a thickness greater than the distance.