Surgical stapling apparatus with lockout assembly
A surgical stapling apparatus includes an anvil half-section, a cartridge receiving half-section, a firing assembly including a push plate, and a lockout assembly. The cartridge receiving half-section defines an elongated channel member configured to receive a single use loading unit (SULU). The lockout assembly is supported in the elongated channel member and includes a lockout assembly that is selectively engageable with the push plate to prevent movement of the push plate relative to the lockout assembly when the anvil half-section and the cartridge receiving half-section are not secured together.
1 . A surgical stapling apparatus comprising:
an anvil half-section;
a cartridge receiving half-section defining an elongated channel member, the elongated channel member configured to receive a single use loading unit (SULU);
a firing assembly including a push plate, the push plate having a distal end portion configured to selectively interlock with a proximal end portion of a drive beam; and
a lockout assembly supported in the elongated channel member and including a spring unit and a lockout that is selectively engageable with the push plate to prevent movement of the push plate relative to the lockout assembly when the anvil half-section and the cartridge receiving half-section are not secured together, wherein a proximal flange of the SULU is configured to drive the push plate downward, wherein the lockout comprises:
a first leg and a second leg;
a stop assembly supported between the first and second leg;
a first foot extending distally from the first leg;
a second foot extending distally from the second leg;
a first mounting nub extending laterally outward from the first foot; and
a second mounting nub extending laterally outward from the second foot, wherein the spring unit is supported by the first mounting nub and the second mounting nub.
2 . The surgical stapling apparatus of claim 1 , wherein the stop assembly includes a stopper and wherein the push plate defines a lockout recess that is configured to receive the stopper.
3 . The surgical stapling apparatus of claim 1 , wherein the spring unit is positioned in engagement with the push plate.
4 . The surgical stapling apparatus of claim 3 , wherein the spring unit includes a leaf spring that contacts the push plate and biases the push plate in a locked position.
5 . The surgical stapling apparatus of claim 4 , wherein the leaf spring is positioned to move between a first position and a second position, wherein in the first position, the lockout maintains the push plate in the locked position and prevents the push plate from moving distally beyond the lockout, and wherein in the second position, the push plate is positioned to advance through the lockout.
6 . The surgical stapling apparatus of claim 5 , wherein the lockout defines a push plate passage through a support wall of the lockout.
7 . The surgical stapling apparatus of claim 6 , wherein the support wall of the lockout is supported between the first and second legs of the lockout.
8 . The surgical stapling apparatus of claim 7 , wherein the legs include shoulders that are receivable by support apertures defined in the elongated channel member to fixedly secure the lockout to the elongated channel member.
9 . The surgical stapling apparatus of claim 5 , the proximal flange vertically movable relative to the elongated channel member to move the leaf spring from the first position to the second position.
10 . The surgical stapling apparatus of claim 1 , wherein the spring unit defines:
a first recess that receives the first mounting nub; and
a second recess that receives the second mounting nub.
11 . The surgical stapling apparatus of claim 10 , wherein the spring unit comprises:
a base secured to a bottom surface of the lockout;
a first sidewall that extends laterally outside the first foot and upwardly from the base, wherein the first recess is defined in the first sidewall; and
a second sidewall that extends that extends laterally outside of the second foot and upwardly from the base, wherein the second recess is defined in the second sidewall.
12 . A surgical stapling apparatus comprising:
an anvil half-section;
a cartridge receiving half-section defining an elongated channel member, the elongated channel member configured to receive a single use loading unit (SULU);
a push plate having a distal end portion configured to selectively interlock with a proximal end portion of a drive beam; and
a lockout assembly including a lockout that is selectively engageable with the push plate to lock the push plate at an acute angle relative to the elongated channel member when the anvil half-section and the cartridge receiving half-section are not secured together, wherein a proximal flange of the SULU is configured to drive the push plate downward, wherein the lockout comprises legs having feet extending distally therefrom, wherein the feet include mounting nubs extending laterally outward therefrom to secure a spring unit to the lockout.
13 . The surgical stapling apparatus of claim 12 , wherein the lockout assembly includes a stopper and wherein the push plate defines a lockout recess that maintains the stopper therein when the push plate is disposed at the acute angle relative to the elongated channel member.
14 . The surgical stapling apparatus of claim 12 , wherein the spring unit is positioned in engagement with the push plate to maintain the push plate at the acute angle.
15 . The surgical stapling apparatus of claim 14 , wherein the spring unit includes a leaf spring that contacts the push plate.
16 . The surgical stapling apparatus of claim 15 , wherein the leaf spring is positioned to move between a first position and a second position, wherein in the first position, the lockout prevents the push plate from moving distally beyond the lockout, and wherein in the second position, the push plate is positioned to advance through the lockout.
17 . The surgical stapling apparatus of claim 16 , wherein the lockout defines a push plate passage through a support wall of the lockout to enable the push plate to advance through the lockout when the leaf spring is disposed in the second position.
18 . The surgical stapling apparatus of claim 17 , wherein the support wall of the lockout is supported between the legs of the lockout and extends above the leaf spring.
19 . The surgical stapling apparatus of claim 18 , wherein the legs include shoulders received in support apertures defined in the elongated channel member to prevent the lockout from moving relative to the elongated channel member.
20 . The surgical stapling apparatus of claim 16 , wherein the proximal flange is movable relative to the elongated channel member to move the leaf spring from the first position to the second position.