Infinitely rotatable tool with finite rotating drive shafts
A catheter rotation drive apparatus includes first and second drives that are engageable to an output shaft. When the first drive is engaged to the output shaft and rotated, the output shaft rotates in an output rotation direction, and when the second drive is engaged to the output shaft and rotated, the output shaft rotates in the output rotation direction.
1. A catheter rotation drive apparatus, comprising:
a first pair of input drives coupled to one another via a first belt, the first pair of input drives comprising a first drive and a first engagement shaft, the first drive coupled to a first drive pulley;
a second pair of input drives coupled to one another via a second belt, the second pair of input drives comprising a second drive and a second engagement shaft, the second drive coupled to a second drive pulley;
wherein each of the first and second drives are engageable to an output shaft;
wherein when the first drive is engaged to the output shaft and rotated, the output shaft rotates in an output rotation direction,
wherein when the second drive is engaged to the output shaft and rotated, the output shaft rotates in the output rotation direction,
wherein when the first engagement shaft of the first pair of input drives is engaged, the second engagement shaft of the second pair of input drives is disengaged, such that when the first drive pulley is rotated in its drive direction, the output shaft is caused to rotate via the first belt in the output rotational direction.
2. The catheter rotation drive apparatus of claim 1 , wherein each of the plurality of input drives are rotatable about respective drive axes that are approximately parallel with one another, and wherein the drive axes are approximately orthogonal to a rotational axis of the output shaft that defines the output rotational direction.
3. The catheter rotation drive apparatus of claim 1 , wherein when the engagement shaft of the second pair is disengaged, the second drive pulley is rotated in a retraction direction that is opposite its drive direction.
4. The catheter rotation drive apparatus of claim 1 , wherein when the engagement shaft of the first pair is disengaged, the engagement shaft of the second pair is engaged, such that when the second drive pulley is rotated in its drive direction, the output shaft is caused to rotate in the output rotational direction.
5. The catheter rotation drive apparatus of claim 1 , wherein an overall output shaft rotation is greater than an input rotation of either of the first and second drives.
6. The catheter rotation drive apparatus of claim 1 , wherein the engagement shafts of the first and second pairs of input drives are each eccentric shafts.
7. The catheter rotation drive apparatus of claim 1 , wherein the first and second belts are O-rings.
8. The catheter rotation drive apparatus of claim 7 , wherein:
the first O-ring is wrapped about:
the engagement shaft of the of the first pair of the input drives;
the first drive pulley; and
the output shaft; and
the second O-ring is wrapped about:
the engagement shaft of the of the second pair of the input drives;
the second drive pulley; and
the output shaft.
9. The catheter rotation drive apparatus of claim 1 , wherein the first and second drives are each not rotatable more than one full revolution.
10. The catheter rotation drive apparatus of claim 1 , wherein the output shaft is rotated in a continuously through engagement of the first drive and engagement of the second drive.
11. A method of fabricating a rotatable catheter comprising:
providing first and second drive shafts that are engageable to an output shaft;
wherein:
when the first drive shaft is engaged to a first engagement shaft and to the output shaft, a second drive shaft is disengaged from a second engagement shaft and from the output shaft, and when the first drive shaft is rotated, the output shaft rotates in an output rotation direction; and
when the second drive shaft is engaged to the second engagement shaft and to the output shaft, the first drive shaft is disengaged from the first engagement shaft and from the output shaft, and when the second drive shaft rotated, the output shaft rotates in the output rotation direction.
12. The method of claim 11 , further comprising:
wherein the first drive shaft is rotatable in a first drive angular direction to cause the output shaft to rotate in the output rotational direction.
13. The method of claim 11 , further comprising:
providing the first engagement shaft such that it is subsequently disengagable from the first drive shaft and from the output shaft via the first belt; and
providing the second engagement shaft such that it is subsequently engagable against the second drive shaft and against the output shaft via the second belt;
wherein the second drive shaft is rotatable in a second drive angular direction to cause the output shaft to rotate in the output rotational direction.
14. The method of claim 13 , further comprising:
providing the first drive shaft such that it is retractable in a retraction direction that is opposite its drive angular direction, when the first engagement shaft is disengaged from the first drive shaft.