A loom comprising: a crank-type drive device; a drive shaft configured to drive the crank-type drive device; and a drive target member configured to be driven by the crank-type drive device, the crank-type drive device including: a crank hub non-rotatably attached to a drive shaft; a holder non-rotatably attached to the crank hub; an eccentric shaft supported by the holder; and a connecting member rotatably supported by the holder via the eccentric shaft and a bearing and connected to the drive target member, the holder including an attached surface that is attached to the crank hub, is orthogonal to an axis line of the drive shaft and is a surface facing toward a tip end of the drive shaft, the crank hub including a plate-shaped attaching part which the attached surface of the holder is attached thereto and has an attaching surface in contact with the attached surface, and a fixing mechanism (22a1) for fixing the crank hub to the drive shaft, the drive shaft being inserted and fitted in the fixing mechanism, characterized in that the crank hub is configured so that the fixing mechanism (22a1) is positioned on the attaching surface -side of the attaching part in a plate thickness direction. a crank-type drive device; a drive shaft configured to drive the crank-type drive device; and a drive target member configured to be driven by the crank-type drive device, the crank-type drive device including: a crank hub non-rotatably attached to a drive shaft; a holder non-rotatably attached to the crank hub; an eccentric shaft supported by the holder; and a connecting member rotatably supported by the holder via the eccentric shaft and a bearing and connected to the drive target member, the holder including an attached surface that is attached to the crank hub, is orthogonal to an axis line of the drive shaft and is a surface facing toward a tip end of the drive shaft, the crank hub including a plate-shaped attaching part which the attached surface of the holder is attached thereto and has an attaching surface in contact with the attached surface, and a fixing mechanism (22a1) for fixing the crank hub to the drive shaft, the drive shaft being inserted and fitted in the fixing mechanism, characterized in that the crank hub is configured so that the fixing mechanism (22a1) is positioned on the attaching surface -side of the attaching part in a plate thickness direction. a crank hub non-rotatably attached to a drive shaft; a holder non-rotatably attached to the crank hub; an eccentric shaft supported by the holder; and a connecting member rotatably supported by the holder via the eccentric shaft and a bearing and connected to the drive target member, the holder including an attached surface that is attached to the crank hub, is orthogonal to an axis line of the drive shaft and is a surface facing toward a tip end of the drive shaft, the crank hub including a plate-shaped attaching part which the attached surface of the holder is attached thereto and has an attaching surface in contact with the attached surface, and a fixing mechanism (22a1) for fixing the crank hub to the drive shaft, the drive shaft being inserted and fitted in the fixing mechanism, characterized in that the crank hub is configured so that the fixing mechanism (22a1) is positioned on the attaching surface -side of the attaching part in a plate thickness direction.