| 摘要 |
Device pertaining to a thread-cutting apparatus which has a driving part 10 and a driven part 24. Fitted between the driving and the driven part are coupling elements having dogs 18,22,70 which, when torque is transmitted between the driving 10 and the driven 24 part, are in mutual engagement. Once a predetermined state between the driving 10 and the driven 24 part is achieved, the dogs 18,22,70 pass out of an engagement position through displacement of an intermediate coupling element 20 against the action of a spring 56,58. The displaceable intermediate coupling element 20 engages in the dog 18 and 22 of both the driving 10 and the driven 24 part respectively. The coupling element 20 having the dogs on the driven part is movable in axially limited measure and is actuated by the axial motion of the driven part 24. The driving 10 and the driven 24 part pass out of an engagement position whenever a predetermined torque value is exceeded, either through displacement of the displaceable intermediate coupling element 20 from driving engagement with the dogs on the driving 10 and the driven 24 part or by the displaceable intermediate coupling element 20 being lifted out of driving engagement with the dog 18 or 22 of the driving 10 or driven 24 part respectively as a result of pressurization from the driven part 24. <IMAGE> |
