A drive manipulation member is configured to be allowed to move to a drive position when an interlock member is at a first position and to be prohibited from moving to the drive position when the interlock member is at a second position. The drive manipulation member is supported rotatably about an axis with respect to the second housing, and is provided with first and second portions extending from the axis in different directions. The first portion is configured to be manipulated by the user. The second portion is provided with a switch operation portion configured to operate a switching unit and an interlock engaging portion configured to engage with or contact with the interlock member. The switch operation portion and the interlock engaging portion are located at different positions from each other in a direction parallel to the axis.
