In accordance with an embodiment, a sheet binding device comprises a sheet shift section, a tape attaching section, an information acquisition section and a controller. The sheet shift section shifts a plurality of sheets forming a sheet bundle from each other at an edge of the sheet bundle. The tape attaching section attaches a tape to the edge of the sheet bundle. The information acquisition section acquires information relating to at least one of the plurality of the sheets, the tape, and a binding method of the sheet bundle by the tape. The controller changes a shift amount between sheets in the plurality of the sheets that is shifted by the sheet shift section based on the information acquired by the information acquisition section.

A sheet binding method involves holding a tape in at least two different locations of the tape; guiding a sheet bundle to between the two different locations of the tape; bending and holding the tape so as to be convex with respect to a conveying direction on a downstream side of the sheet bundle; and contacting the convex tape with the sheet bundle to bind the sheet bundle.

A sheet binding apparatus according to an embodiment includes a tape holding section and a guide section. The tape holding section holds a tape in at least two parts. The guide section guides a sheet bundle to between the two parts of the tape. The tape holding section bends and holds the tape to be convex to a conveying direction downstream side of the sheet bundle.

A sheet binding device includes a sheet shifting unit, a tape cutter, and a tape attachment unit. The sheet shifting unit has a guide and is configured to stack multiple sheets on the guide with edge portions that are shifted from each other to form a sheet bundle. The tape cutter cuts tape with a target length that is varied in accordance with a thickness of the sheet bundle. The tape attachment unit is configured to attach the cut tape having the target length to an edge portion of the sheet bundle.

A sheet binding apparatus includes a sheet conveyer, a tape holder, and first and second rollers. The sheet conveyer is configured to convey a sheet bundle with a leading end shifted, the sheet bundle having opposing first and second surfaces. The tape holder is configured to hold a tape at a position to which the leading end reaches such that the tape adheres to the leading end. The leading end with the tape passes and is pressed between the first and second rollers. The second roller is positioned upstream in the sheet forward direction from the first roller and to face the second surface of the sheet bundle. An angle between a line perpendicular to the sheet forward direction and a line passing rotational axes of the first and second rollers is greater than 0 and less than 90.

According to one embodiment, a sheet binding device includes a first mounting part, a second mounting part, and a mounting adjustment part. The first mounting part mounts a tape on an edge part of a sheet bundle. The second mounting part is opposite to the first mounting part in a sheet bundle thickness direction. The mounting adjustment part is capable of adjusting a mounting gap between the first mounting part and the second mounting part based upon a thickness of the sheet bundle. The mounting gap is equal to or smaller than the thickness of the sheet bundle before the sheet bundle is inserted between the first mounting part and the second mounting part.

According to one embodiment, a sheet binding apparatus includes a first roller, a second roller, and a nip-pressure adjusting section. The first roller attaches a tape to an edge portion of a sheet bundle. The second roller is opposed to the first roller in the sheet bundle thickness direction. The nip-pressure adjusting section is capable of adjusting, on the basis of the position of an edge portion leading end of the sheet bundle, a pressing force of a nip formed by the first roller and the second roller. Before the sheet bundle is inserted between the first roller and the second roller, an interval between the first roller and the second roller is equal to or smaller than the thickness of the sheet bundle.

According to one embodiment, a sheet binding device includes a first mounting part, a second mounting part, and a mounting adjustment part. The first mounting part mounts a tape on an edge part of a sheet bundle. The second mounting part is opposite to the first mounting part in a sheet bundle thickness direction. The mounting adjustment part is capable of adjusting a mounting gap between the first mounting part and the second mounting part based upon a thickness of the sheet bundle. The mounting gap is equal to or smaller than the thickness of the sheet bundle before the sheet bundle is inserted between the first mounting part and the second mounting part.

According to one embodiment, a sheet binding apparatus includes a first roller, a second roller, and a nip-pressure adjusting section. The first roller attaches a tape to an edge portion of a sheet bundle. The second roller is opposed to the first roller in the sheet bundle thickness direction. The nip-pressure adjusting section is capable of adjusting, on the basis of the position of an edge portion leading end of the sheet bundle, a pressing force of a nip formed by the first roller and the second roller. Before the sheet bundle is inserted between the first roller and the second roller, an interval between the first roller and the second roller is equal to or smaller than the thickness of the sheet bundle.

A sheet binding apparatus according to an embodiment includes a tape holding section and a guide section. The tape holding section holds a tape in at least two parts. The guide section guides a sheet bundle to between the two parts of the tape. The tape holding section bends and holds the tape to be convex to a conveying direction downstream side of the sheet bundle.