Torque limiter

A torque limiter comprised of mutually facing torque input and output parts capable of mutual engagement and disengagement,

• a torque transmission part capable of mutually engaging or disengaging said torque input and output parts for transmitting or releasing torque applied therebetween,
• torque control means for maintaining said torque transmission part in an engaged condition when applied torque is lower than a stipulated level, and further capable of allowing release of the engaged condition of said torque transmission part when applied torque is higher than the aforesaid stipulated level, and
• a ball bearing structure rotatably supporting both said torque input and output parts, ball parts employed by said bearing structure being maintained in contact at two points on an outer groove surface formed on an inner circumference of said torque output part, and at two points on an inner groove surface formed on an outer circumference of said torque input part,
• wherein said torque transmission part resides in multiple orifices formed through said torque output part, said torque input part has a plurality of concavities opposite to said orifices, and said torque control means operates said torque transmission part as means of forming a joint between said torque transmission part and said concavities such that operation of said torque control means is not applied to said torque output part.