Rotary input for lever actuation
A medical device includes a lever with an applied force position, a load position, and a fulcrum position. A first cable extends from the applied force position of the lever to a first capstan, the first cable wrapping around the first capstan. A second cable extends from the applied force position of the lever to a second capstan, the second cable wrapping around the second capstan. A rod couples the load position of the lever and a surgical end effector. The first and second capstans may be fixed to an axle. The axle may receive a rotational input from a rotary actuator. A hand wheel may be coupled to the axle. There may be a spring between a support structure and the lever to bias the lever to rotate about the fulcrum position of the lever.
1. A medical device comprising:
a lever comprising an applied force position, a load position, and a fulcrum position;
a first capstan;
a second capstan;
a first cable extending from the applied force position of the lever to the first capstan, the first cable wrapping around the first capstan;
a second cable extending from the applied force position of the lever to the second capstan, the second cable wrapping around the second capstan;
a surgical end effector; and
a rod coupled between the load position of the lever and the surgical end effector.
2. The medical device of claim 1 , further comprising:
an axle, the first and second capstans being fixed to the axle.
3. The medical device of claim 2 , further comprising:
an input connection configured to receive a rotational input from a rotary actuator, the input connection being coupled to the axle.
4. The medical device of claim 2 , further comprising:
a hand wheel coupled to the axle.
5. The medical device of claim 1 , further comprising:
an idler pulley;
the first cable passing over the idler pulley between the applied force position of the lever and the first capstan;
the second cable passing over the idler pulley between the applied force position of the lever and the second capstan.
6. The medical device of claim 1 , further comprising:
a support structure; and
a spring between the support structure and the lever and positioned to bias the lever to rotate about the fulcrum position of the lever.
7. The medical device of claim 1 , wherein the load position of the lever is distal of the fulcrum position of the lever from the applied force position of the lever.
8. The medical device of claim 1 , wherein the load position of the lever is proximal of the fulcrum position of the lever from the applied force position of the lever.