A conveyor includes a first conveyance path along which a sheet is conveyed in a first direction, a second conveyance path along which the sheet is conveyed in a second direction different from the first direction, a switching part configured to switch a conveyance direction of the sheet between the first direction and the second direction, a sheet detector configured to detect the sheet at the switching part, a conveyance system driver configured to convey and stop the sheet, and circuitry configured to control the conveyance system driver to stop conveyance of the sheet in a predetermined condition, control the sheet detector to detect the sheet at the switching part, and control the switching part to switch the conveyance direction of the sheet from the first direction to the second direction when the sheet detector does not detect the sheet at the switching part.

A sheet suction device includes a sheet bearer having a plurality of suction holes on a plurality of bearing areas, a rotational portion having a plurality of holes that is connectable to the plurality of suction holes, a suction unit configured to suck air via the plurality of holes of the rotational portion. The sheet bearer bears a plurality of sheets on the plurality of bearing areas of the circumferential surface of the sheet bearer and rotates. The rotational portion rotates in a same cycle of the sheet bearer. The sheet suction device further includes a switching unit that switches combinations of whether or not to suck the air among the plurality of bearing areas of the sheet bearer according to a phase of rotation of the sheet bearer or the rotational portion.

A sheet suction device includes a bearing member configured to bear a sheet on a circumferential surface of the bearing member and rotate, a plurality of suction holes in a bearing region in the circumferential surface of the bearing member, a suction device connected to the plurality of suction holes, the suction device configured to suck the sheet through the plurality of suction holes, and a rotary valve between the bearing member and the suction device. The rotary valve includes: a first member communicating with the suction device, and a second member contacting the first member, the second member communicating with the plurality of suction holes. The first member includes a first groove on a side surface in a circumferential direction of the first member, the first groove communicating with the suction device.

A conveying unit includes a rotatable roller having a first through-hole between the inside and the outside of the roller. A cylindrical member inside the roller has an opening and defines an annular chamber between the member and the roller. An insert borne by the roller inserted in the first through-hole thereof and contacting an external surface of the cylindrical member has a second through-hole in communication with the outside of the roller and extending through the first through-hole and the annular chamber. The first through-hole of the opening is configured such that, when the roller rotates, the insert transits at the opening, temporarily placing the outside of the roller in fluid communication with the annular chamber via the second through-hole, so that a sheet outside the roller and at the first through-hole is pulled against the roller by aspirating means and is conveyed.

A sheet suction device includes a sheet bearer having a plurality of suction holes, a suction unit, a first member, and a second member. The first member has grooves arranged in a radial direction, and each of the grooves extends in a circumferential direction. The second member has a plurality of hole rows including a plurality of holes. The plurality of holes in each of the plurality of hole rows is arranged in the circumferential direction, and the plurality of hole rows is arranged in the radial direction. When the first member rotates with respect to the second member, the number of holes communicating with the grooves is changed to change the number of the plurality of suction holes communicating with the suction unit. The plurality of holes includes two or more holes that simultaneously communicate with the suction unit when the first member rotates by a unit rotation amount.

A sheet suction device includes a bearing member configured to bear a sheet on a circumferential surface of the bearing member and rotate, a plurality of suction holes in a bearing region in the circumferential surface of the bearing member, a suction device connected to the plurality of suction holes, the suction device configured to suck the sheet through the plurality of suction holes, and a rotary valve between the bearing member and the suction device. The rotary valve includes: a first member communicating with the suction device, and a second member contacting the first member, the second member communicating with the plurality of suction holes. The first member includes a first groove on a side surface in a circumferential direction of the first member, the first groove communicating with the suction device.

A sheet suction device includes a sheet bearer having a plurality of suction holes on a plurality of bearing areas, a rotational portion having a plurality of holes that is connectable to the plurality of suction holes, a suction unit configured to suck air via the plurality of holes of the rotational portion. The sheet bearer bears a plurality of sheets on the plurality of bearing areas of the circumferential surface of the sheet bearer and rotates. The rotational portion rotates in a same cycle of the sheet bearer. The sheet suction device further includes a switching unit that switches combinations of whether or not to suck the air among the plurality of bearing areas of the sheet bearer according to a phase of rotation of the sheet bearer or the rotational portion.

A sheet suction device includes a bearing member configured to bear a sheet on a circumferential surface of the bearing member and rotate in a first direction, a plurality of suction holes in a bearing region in the circumferential surface of the bearing member, a suction device connected to the plurality of suction holes, the suction device configured to suck the sheet through the plurality of suction holes, and a first member between the plurality of suction holes and the suction device, the first member rotatable in a second direction different from the first direction to change a suction region of the suction device connected to the plurality of suction holes. A rotation of the first member in the second direction expands the suction region of the suction device in the bearing region of the bearing member.

A vacuum roller system and a method of operating the vacuum roller system can include a group of vacuum rollers operable to move a sheet of media through a dryer. The vacuum rollers do not require a vacuum to be drawn between the vacuum rollers. Each vacuum roller can include a plenum operable to direct the vacuum to a top portion of the vacuum roller to drive the sheet of media from one roller to the next roller. The plenum can engage vacuum holes in a rotating vacuum roller when the vacuum holes in the vacuum roller are aligned with the plenum.

A bonding apparatus includes a first holder, a first transforming device, a second holder, a second transforming device, a suction device and a control device. The first holder attracts and holds a first substrate from above. The first transforming device transforms the first substrate held by the first holder such that a central portion of the first substrate is protruded downwards. The second holder is provided under the first holder, and attracts and holds a second substrate, which is to be bonded to the first substrate, from below. The second transforming device transforms the second substrate held by the second holder such that a central portion of the second substrate is protruded upwards. The suction device generates different attracting forces in multiple division regions included in an attraction region of the second substrate. The control device controls the suction device.