Mechanism for converting unidirectional rotative movement into alternating bidirectional rotative movement
AssigneeInstitut Straumann AG
InventorOswald Tschudin
Life of this patent
Estimating the term…
Abstract
A drive shaft continuously rotating in a single direction operates to drive a driven shaft with alternating bidirectional rotative movement through a gear transmission which includes a first gear mounted on the drive shaft and second and third gears mounted on the driven shaft, with the first gear having teeth on only a portion thereof, the teeth alternately engaging the second and third gears as the drive shaft rotates. The gear teeth on the first, second and third gears have a tooth pitch t.sub.0 and the teeth on the second and third gears are offset relative to each other by an arc length measured along the pitch circle of the gear which is not grater than one-fourth of the tooth pitch t.sub.0.
Claims25
A mechanism for converting unidirectional rotative movement into alternating bidirectional rotative movement comprising:
- a drive shaft adapted for unidirectional rotative movement
- a driven shaft adapted to be driven with alternating bidirectional rotative movement;
- first gear means in continuous rotational connection with said drive shaft having gear teeth thereon;
- second and third gear means on said driven shaft having gear teeth thereon;
- said gear teeth of said first gear means being adapted to alternately engage said gear teeth on said second and third gear means in order to alternately drive said driven shaft in opposed rotative directions;
- said gear teeth on said first, said second and said third gear means having a tooth pitch t.sub.0 with the gear teeth on said second and third gear means being offset relative to each other by an arc-length measured along pitch circles of said second and third gear means, which arc-length is not greater than one-fourth of said tooth pitch t.sub.0.
A mechanism for converting unidirectional rotative movement into alternating bidirectional rotative movement comprising a driven shaft adapted to be driven with alternating bidirectional rotative movement;
- a drive shaft undergoing unidirectional rotative movement for driving said driven shaft;
- and transmission means interposed between said drive shaft and said driven shaft, said transmission means comprising first, second and third gear means, said first gear means being in continuous rotational connection with said drive shaft and operating as a driving gear wheel, said second and said third gear means comprising equally sized gears arranged in continuous rotational connection with said driven shaft, said first gear means having at least one section thereof not containing gear teeth, said first, said second and said third gear means being arranged in such a way that during rotation of said drive shaft said first gear means alternately engages with said second and said third gear means and that mutually corresponding positions of teeth of said second and third gear means having a tooth pitch t.sub.0 are offset relative to one another by an arc a measured on their pitch circles when one projects the two said positions on one another by displacement thereof without rotation, wherein
- 0<.vertline.a .vertline..ltoreq.t.sub.0 /4
- and wherein the second or third gear means, not engaged at the time with said first gear means leads the engaged one of said second or third gear means by said arc a.
Dependencies are inferred from the claim text.