Step-by-step motor able to carry out up-and-down motion

A step-by-step motor able to carry out up-and-down motion comprising:

• a housing formed with an accommodating chamber in the interior, said accommodating chamber provided inside with a recessed chamber, said recessed chamber provided with a rectangular slot, said rectangular slot having its upper side bored with an insert hole, said housing having one side wall bored with an opening, an inner wall defining said opening cut with a slide groove;
• a connecting base assembled on one side wall of said housing, said connecting base disposed with a slide rail at one side corresponding with said opening of said housing, said connecting base provided with a plurality of connecting holes in the interior;
• a top rod having its upper end inserted through said insert hole of said housing, said top rod having the section near its lower end provided with male threads, said top rod having an intermediate wall fixed thereon with a square stopper, said top rod having said threaded upper end threadably combined with a locking knob;
• a bearing positioned in said recessed chamber of said housing;
• a connecting member positioned under said bearing and having its upper end inserted through said bearing, said connecting member bored with a threaded hole in the center;
• a magnet fitted around said connecting member;
• a right-handed coil received in said accommodating chamber of said housing, said right-handed coil having one outer side disposed with connecting terminals, said right-handed coil having its inner and outer circumferential wall respectively covered with claws spaced apart;
• a reverse coil received in said accommodating chamber of said housing and overlapped with said right-handed coil, said reverse coil having one outer side secured with parallel connecting terminals, said reverse coil having its inner and outer circumferential wall respectively covered with claws spaced apart;
• and
• a bottom cover closed on a bottom of said housing, said bottom cover provided with an annular recess near its circumferential edge, said bottom cover bored with a recessed hole in the center.