Forceps including a pre-loaded handle latch
A surgical device comprising: a closure assembly including: (a) a latch unit comprising: (A) a hook latch, having a home position, (B) a forward bias constraint, (C) a rearward bias constraint, and (D) a bias member extending between the forward bias constraint and the rearward bias constraint so that the bias member has a pre-load when the hook latch is in the home position; (b) a movement unit including a bar that is movable relative to the latch unit so that the bar is movable in a prescribed motion into contact with the latch unit to create a locked state; and wherein the bar moves into contact with the hook latch driving the hook latch in a first direction, away relative to the home position, and then the hook latch is moved by the bar in a second direction relative to the home position, and a loading of the bias member is increased from the pre-load when the hook latch is moved in either the first direction away from the home position or the second direction away from the home position.
1. A closure assembly for a surgical device comprising:
a latch unit including:
a hook latch having a home position;
a forward bias constraint;
a rearward bias constraint; and
a double acting bias member constrained between the forward bias constraint and the rearward bias constraint and having a pre-load when the hook latch is in the home position, wherein a loading of the bias member is increased from the pre-load when the hook latch is moved in either a first direction away from the home position or a second direction away from the home position; and
a movement unit including a projection that is movable relative to the latch unit;
wherein the hook latch is movable by the projection in the first and second directions away from the home position.
2. The closure assembly of claim 1 , wherein the projection is movable relative to the latch unit in a prescribed motion into contact with the latch unit to create a locked state.
3. The closure assembly of claim 1 , wherein the bias member contacts a rearward movable bias constraint as a latch plate moves in the first direction so that a load on the bias member is increased relative to the pre-load.
4. The closure assembly of claim 3 , wherein the bias member contacts a forward movable bias constraint as the latch plate moves in the second direction so that a load on the bias member is increased relative to the pre-load.
5. The closure assembly of claim 4 , wherein the forward movable bias constraint is a forward post or a forward contact surface and the rearward movable bias constraint is a rearward post or a rearward contact surface.
6. The closure assembly of claim 1 , wherein the bias member is a compression spring that is in contact with both the forward bias constraint and the rearward bias constraint to retain the pre-load on the compression spring.
7. The closure assembly of claim 1 , wherein the latch unit includes a selection plate that is movably connected to a latch plate.
8. The closure assembly of claim 7 , wherein the selection plate moves the latch unit between a lockable state and an unlockable state.
9. The closure assembly of claim 8 , wherein the selection plate includes an unlockable state detent and a lockable state detent that locks the latch unit in the lockable state or the unlockable state.
10. The closure assembly of claim 1 , wherein the projection extends from a trigger of the movement unit, and wherein actuation of the trigger moves the projection relative to the latch unit.
11. The closure assembly of claim 1 , wherein the latch unit is connected to a ground member.
12. The closure assembly of claim 11 , wherein the ground member comprises a handle.
13. The closure assembly of claim 1 , wherein the pre-load is greater than 0 N.
14. The closure assembly of claim 13 , wherein the loading of the bias member is increased over the pre-load by about 1 N or more.
15. A closure assembly for a surgical device comprising:
a latch unit including:
a hook latch having a home position;
a forward bias constraint;
a rearward bias constraint; and
a double acting bias member constrained between the forward bias constraint and the rearward bias constraint and having a pre-load when the hook latch is in the home position, wherein a loading of the bias member is increased from the pre-load when the hook latch is moved in a first direction away from the home position and a second direction away from the home position.
16. The closure assembly of claim 15 , further comprising a movement unit including a projection that is movable relative to the latch unit in a prescribed motion.
17. The closure assembly of claim 16 , wherein contact between the projection and the latch unit creates a locked state.
18. The closure assembly of claim 16 , wherein the hook latch is movable by the projection in the first and second directions away from the home position.
19. A closure assembly for a surgical device comprising:
a latch unit connected to a ground member and including a hook latch having a home position and a double acting bias member constrained between a forward bias constraint and a rearward bias constraint, the bias member having a pre-load when the hook latch is in the home position, wherein a loading of the bias member is increased from the pre-load when the hook latch is moved in a first direction away from the home position and a second direction away from the home position; and
a movement unit including a projection that is movable relative to the latch unit between an unlocked state and a locked state.