Perforating apparatus, sheet processing apparatus, and image forming apparatus

An image forming apparatus comprising a perforating apparatus that conducts perforating processing on sheet material received from the image forming apparatus, said perforation apparatus comprising:

• a perforation device including a punch configured to punch holes on said sheet material;
• a detection disk having at least one cutaway part, the detection disk being rotatably mounted at one end of the perforation device;
• a first drive motor fixedly mounted on a stay and connectable to an axial end of the perforation device for driving said perforation device to conduct said perforation processing on said sheet material;
• a base, having a plurality of rollers, fixedly mounted on the perforating apparatus, the perforation device being insertable into the stay and configured to move lengthwise on the stay;
• a home position sensor mounted on the base;
• and
• a controller configured to adjust a position of the perforation device in a lateral registration direction based on a signal output from the home position sensor corresponding to at least one of an amount of cutaway parts and a position of the cutaway parts on the detection disk,
• wherein said perforation device is integrally insertable into and detachable from said first drive motor such that a first end of a rotational spindle of the perforation device is directly contactable with the first drive motor fixed to a non-moving part of the perforation device.