Tractor and printer using the same

摘要

According to one embodiment, a tractor comprises a guide shaft, a first belt unit, a second belt unit, a fixing unit and a connecting unit. The first belt unit is supported by the guide shaft so as to move in an axis direction of the guide shaft. The second belt unit is arranged to face the first belt unit in the axis direction of the guide shaft and supported by the guide shaft. The fixing unit, which is movably supported by the guide shaft in the axis direction of the guide shaft and is capable of being fixed on the guide shaft. The connecting unit configured to connect the first belt unit to the fixing unit with a clearance in the axis direction of the guide shaft.

主权项

1. A tractor, comprising:
a guide shaft; a first belt unit, supported by the guide shaft so as to move in an axis direction of the guide shaft, which includes a rotatable endless pin belt which is provided with a plurality of pins inserting into one of a pair of feeding hole lines formed on a tractor paper; a second belt unit, arranged to face the first belt unit in the axis direction of the guide shaft and supported by the guide shaft, which includes a rotatable endless pin belt which is provided with a plurality of pins inserting into the other feeding hole line formed on the tractor paper; a fixing unit, which is movably supported by the guide shaft in the axis direction of the guide shaft and is capable of being fixed on the guide shaft; and a connecting unit configured to connect the first belt unit to the fixing unit with a clearance in the axis direction of the guide shaft; wherein the fixing unit includes: a cylinder member having an elastic part into which the guide shaft is inserted, wherein the cylinder member is arranged on a member that is a different member from the first belt unit to regulate the movement of the first belt unit around the axis of the guide shaft; and an operating member, which is arranged on a member that is a different member from the first belt unit, into which the cylinder member is inserted, and which is able to move around the axis of the guide shaft at between a fixed position where the elastic part is pressed to forcibly contact the guide shaft so as to fix the fixing unit on the guide shaft and a release position where the fixing of the fixing unit on the guide shaft is released by releasing the pressed connection between the fixing unit and the guide shaft; the cylinder member includes: a cylinder unit, having one end of which is provided with the elastic part and inserted with the guide shaft; and a third clamping part arranged at the other end of the cylinder unit; and the first belt unit includes: a fourth clamping part, clamping with the third clamping part to regulate the rotation of the cylinder member around the axis of the guide shaft, which is able to move relatively with respect to the third clamping part in the axis direction of a third guide shaft; the elastic part includes a plurality of elastic sheets; the third clamping part includes a plurality of first clamping sheets; and the fourth clamping part includes a plurality of second clamping sheets; wherein the plurality of elastic sheets extend from one end of the cylinder unit along the axis direction of the guide shaft and are arranged with a space each other around the axis of the guide shaft; the plurality of first clamping sheets extend from the other end of the cylinder unit along the axis direction of the guide shaft and are arranged with a space each other around the axis of the guide shaft; and the plurality of second clamping sheets extend along the axis direction of the guide shaft and are arranged with a space each other around the axis of the guide shaft to clamp with the first clamping sheets.