| 摘要 |
PROBLEM TO BE SOLVED: To provide a worm reduction machine including a back-lash removal mechanism so as to eliminate rotational looseness caused by a contact clearance between teeth surfaces generated when the worm reduction machine rotates in a normal or reverse direction.SOLUTION: In order to eliminate a back-lash between each of the worms 6a, 6b and the worm wheels 7a, 7b, teeth of each of the worm wheels are always held by the teeth of the right and left worms. That is, there is provided another additional driving shaft 10 that is rotated in the same direction through a gear in parallel with the driving shaft 3 of the motor 4. Each of the worms having the same torsion angle is applied to the driving shaft 3 through keys 3b, 10b so as to attain an axial slidable action and a rotational force power transmittable action, the worms are depressed in opposite directions to each other by compression springs having shaft protrusions acted as reaction force receivers, the two worm wheels engaged with the worms are arranged at a component rotary driving shaft 11 that crosses with the worm shaft at a right angle. One-way clutch is arranged between the worm wheels and the component rotary driving shaft so as not to increase the rotational force power by two times in such a way that their operations act in the opposite direction to each other. |
