Surgical Instrument Including A Locking Assembly

ES 2 392 797 T3

DESCRIPTION

Surgical instrument that has a plastic surface

Technical field

The present description relates to a surgical instrument and a disposable loading unit that include a plastic surface thereon. More particularly, the present disclosure relates to a surgical instrument that includes a plastic surface on at least one of a closure apparatus and a contact surface of a tool assembly.

Background

Surgical devices in which tissue is first grasped or clamped between an opposing jaw structure and then attached by surgical fasteners are well known in the art. In some instruments, a scalpel is provided to cut the tissue that has been joined by the fasteners. The fasteners are typically in the form of surgical staples although two-part polymeric fasteners can also be used.

Instruments for this purpose may include two elongated elements which are used respectively to catch or hold tissue. Typically, one of the elements carries a staple cartridge that houses a plurality of staples arranged in at least two lateral rows while the other element has an anvil that defines a surface to form the legs of the staple as the staples are driven. from the staple cartridge. In some instruments, the closure of the two elongated elements, or tool assembly, is effected by actuation of a movable handle that moves a drive beam having a closure apparatus thereon into a contact surface of a tool set, thus bringing together the elements of the tool set. There may be a large frictional force between the closure apparatus and the contact surface of the tool assembly, thus possibly requiring a relatively large amount of force to be applied to the movable handle.

US 2006/016853 discloses a surgical stapling device that includes an independently rotatable tool assembly. The tool assembly includes an anvil and cartridge assembly that are movable relative to each other between spaced and approximate positions. The closure element of US 2006/016853 is made of a heavy gauge material. The preamble of appended claim 1 is based on this description.

Summary

The present description refers to claim 1. The body part extends distally from the handle part and defines a first longitudinal axis. The movable handle is located in the handle part and cooperates mechanically with an actuating element. The tool assembly is supported adjacent a distal end of the body portion and includes an anvil, a cartridge assembly, and a contact surface. The actuating beam includes a proximal engagement portion located adjacent a proximal end thereof and is configured to engage with a portion of the actuating element. The closure apparatus is located adjacent a distal end of the drive beam and is configured to engage with the contact surface of the tool assembly and includes a cutting surface in a disclosed embodiment. At least partial actuation of the movable handle moves the closure apparatus distally to engage the contact surface to approach the anvil and cartridge assembly.

At least a horizontal part of the closure apparatus includes a plastic cap having a reinforced section. It is disclosed that at least a part of the closure apparatus is made of plastic or overmolded with plastic.

In a disclosed embodiment, the drive beam includes a plurality of layers. It is also disclosed that the closure apparatus has an I-shaped cross section.

In one embodiment, the tool assembly defines a second longitudinal axis and is movable from a first position in which the second longitudinal axis is substantially aligned with the first longitudinal axis to a second position in which the second longitudinal axis is arranged to form a angle with the first longitudinal axis. In this embodiment, the tool assembly can be hinged.

In one embodiment, the closure apparatus is part of a disposable loading unit. The present description also refers to a disposable loading unit that includes features of the closure apparatus and tool assembly, as described above.

Description of the drawings

Various embodiments of the disclosed surgical instrument are now disclosed herein with reference to the drawings, in which:

Figure 1 is a side perspective view from the distal end of one embodiment of the disclosed surgical instrument with articulated tool assembly;

Figure 1A is a side perspective view from the proximal end of a disposable loading unit (DLU) of the surgical instrument shown in Figure 1 that includes the tool assembly;

Figure 2 is a side perspective view of the distal end of the mounting assembly and tool assembly, with parts separated, of the DLU of the surgical instrument shown in Figure 1 Figure 3 is a side perspective view of the mounting assembly and of the proximal body portion of the DLU shown in Figure 1A with parts separated;

Figure 3A is a side perspective view of a coupling element of the surgical instrument shown in Figure 1;

Figure 3B is a side perspective view of a top mounting portion of the DLU mounting assembly of the surgical instrument shown in Figure 1;

Figure 3C is a side perspective view of a lower mounting portion of the DLU mounting assembly of the surgical instrument shown in Figure 1;

Figure 3D is a top side perspective view of the proximal body portion, mounting assembly, and tool assembly of the surgical instrument dLu with the tool assembly in its non-articulated position;

Figure 3E is a top side perspective view of the proximal body portion, mounting assembly, and tool assembly shown in Figure 3D with the tool assembly in an articulated position;

Figure 3F is a side perspective view from below of the proximal body portion, mounting assembly, and tool assembly of the DLU of the surgical instrument with the tool assembly in its non-articulated position;

Figure 3G is a side perspective view from below of the proximal body portion, mounting assembly, and tool assembly shown in Figure 3F with the tool assembly in an articulated position;

Figure 4 is a side cross-sectional view of the DLU tool assembly shown in Figure 1A;

Figure 5 is a top perspective view of the locking element actuator of the proximal body portion locking mechanism shown in Figure 3;

Figure 6 is a bottom perspective view of a locking member of the locking mechanism shown in Figure 3;

Figure 7 is a top view of the proximal end of the DLU proximal body portion shown in Figure 1A with the locking mechanism in its locked position;

Figure 8 is a cross-sectional view taken along section lines 8-8 of Figure 7;

Figure 9 is a top view of the proximal end of the DLU proximal body portion shown in Figure 1A with the locking mechanism in its unlocked position;

Figure 10 is a cross-sectional view taken along section lines 10-10 of Figure 9;

Figure 11 is a side perspective view of the DLU and surgical instrument shown in Figure 1 prior to attachment of the DLU to the surgical instrument;

Figure 12 is a top view of the proximal end of the DLU and the distal end of the surgical instrument shown in Figure 11 prior to attachment to the distal end of the surgical instrument;

Figure 13 is a top view of the proximal end of the DLU shown in Figure 11 as the DLU is linearly advanced toward the distal end of the surgical instrument;

Figure 14 is a top view of the proximal end of the DLU and the distal end of the surgical instrument shown in Figure 12 after the DLU has been linearly advanced but before locking the DLU to the surgical instrument;

Figure 15 is a top view of the proximal end of the DLU and the distal end of the surgical instrument shown in Figure 13 after the DLU has been linearly advanced and rotatably locked to the surgical instrument;

Figure 16 is a perspective view of a locking assembly for use with a surgical instrument according to one embodiment of the present disclosure;

Figure 17 is a perspective view of various components of the lock assembly of Figure 16;

Figure 18 is an enlarged perspective view of a portion of the locking assembly of Figures 16 and 17 illustrated with the articulated tool assembly in a non-articulated position;

Figure 19 is an enlarged perspective view of a portion of the lock assembly of Figures 16-18 and including a link;

Figure 20 is an enlarged perspective view of a portion of the locking assembly of Figures 16-19 illustrated with the articulated tool assembly in an articulated position;

Figure 21 is an enlarged perspective view of another locking assembly for use with a surgical instrument in accordance with one embodiment of the present disclosure;

Figure 22 is an enlarged bottom perspective view of the lock assembly of Figure 21;

Fig. 23 is a perspective view of a drive beam having a plurality of layers and a closure apparatus according to an embodiment of the present disclosure;

Figure 24 is a perspective view of the drive beam and closure apparatus of Figure 23 with parts separated;

Figure 25 is a cross-sectional view of a portion of the drive beam and closure apparatus of Figures 23 and 24;

Figure 26 is a cross-sectional view of a drive beam and a closure apparatus according to an embodiment of the present invention;

Figure 27 is a cross-sectional view of the drive beam and closure apparatus of Figure 26;

Figure 28 is a perspective view of a tool assembly according to one embodiment of the present disclosure; ^Y Figure 29 is an assembly view of the tool assembly of Figure 28.

Detailed description of realizations

Now disclosed surgical instrument and DLU embodiments will now be described in detail with reference to the drawings, in which like reference numerals designate identical or corresponding elements in each of the various views.

Referring to FIG. 1, surgical instrument 500 includes a handle portion 510, a body portion 512, and a disposable loading unit ("DLU") 16. The handle portion 510 includes a stationary handle 514 and a movable handle or trigger 516. The movable handle 516 is movable relative to the stationary handle 514 to advance a control rod 520 protruding from the distal end of the portion 512 body. Handle portion 510 and body portion 512 may be constructed in the manner disclosed in US Patent No. 6,330,965. Alternatively, other surgical instruments can be used with the DLU 16 to perform endoscopic surgical procedures.

Referring briefly to Figures 1 and 1A, the DLU 16 includes a tool assembly 17, a proximal body portion 200, and a mounting assembly 202. Body portion 200 has a proximal end adapted to releasably engage with the distal end of a surgical instrument 500 (FIG. 11) in a manner to be discussed in detail below. Mounting assembly 202 is pivotally secured to a distal end of body portion 200 and is fixedly secured to a proximal end of tool assembly 17. Pivotal movement of mounting assembly 202 about an axis perpendicular to a longitudinal axis of body portion 200 effects articulation of tool assembly 17 between a non-articulated position in which the longitudinal axis of tool assembly 17 is aligned with the longitudinal axis of the body portion 200 and an articulated position in which the longitudinal axis of the tool assembly 17 is disposed at an angle to the longitudinal axis of the body part 200.

Referring to Figures 2-4, the tool assembly 17 includes a cartridge assembly 18 and an anvil assembly 20. Anvil assembly 20 includes an anvil portion 28 having a plurality of staple deformation recesses 30 (FIG. 4) and a cover plate 32 secured to an upper surface of anvil portion 28. Cover plate 32 and anvil portion 28 define a cavity 34 (FIG. 4) therebetween that is dimensioned to accommodate a distal end of a drive assembly 212 (FIG. 3). Cover plate 32 encloses the distal end of actuation assembly 212 to avoid pinching tissue during actuation of DLU 16.

ES 2 392 797 T3

A longitudinal slot 38 extends through the anvil portion 28 to facilitate passage of a retaining lip 40 of the actuator assembly 212. A camming surface 42 formed on the anvil portion 28 is positioned to engage with a pair of cam members 40a supported on the retaining flange 40 of the drive assembly 212 to effect rapprochement of the anvil and cartridge assemblies. A pair of pivot elements 44 are formed. A pair of stabilizing elements 50 engage with a respective flange 52 formed on carriage 48 to prevent anvil portion 28 from sliding axially relative to staple cartridge 54 as camming surface 42 pivots about. of the pivot elements 44.

Cartridge assembly 18 includes carriage 48 defining an elongated support channel 56 that is dimensioned and configured to house staple cartridge 54. corresponding tabs 58 and slots 60 formed along staple cartridge 54 and elongated support channel 56, respectively, function to retain staple cartridge 54 at a fixed location within support channel 56. A pair of support braces 62 formed on the staple cartridge 54 are positioned to abut the side walls of the carriage 48 to further stabilize the staple cartridge 54 within the support channel 56. Carriage 48 has grooves 46 to accommodate pivot elements 44 of anvil portion 28 and allow anvil portion 28 to move between the spaced and approximate position.

Staple cartridge 54 includes retention slots 64 (FIG. 2) for accommodating a plurality of staples or fasteners 66 and pushers 68. A plurality of laterally spaced longitudinal slots 70 extend through staple cartridge 54 to accommodate wedges 72 vertical cam loops of a drive chute 74 (FIG. 2). A central longitudinal slot 76 extends along substantially the length of the staple cartridge 54 to facilitate passage of the scalpel blade 78 (FIG. 4). During operation of surgical stapler 10, drive assembly 212 abuts drive slide 74 and pushes drive slide 74 through longitudinal slots 70 of staple cartridge 54 to advance cam wedges 72 to sequentially contact the pushers 68. The pushers 68 translate vertically along the cam wedges 72 within the fastener retaining slots 64 and push the fasteners 66 from the retaining slots 64 into the staple deformation cavities 30 ( Figure 4) of the anvil assembly 20.

Referring to FIG. 3, the mounting assembly 235 includes an upper mounting portion 236 and a lower mounting portion 238. A centrally located pivot element 284 extends from the upper mounting portion 236 through a respective opening 246a formed in a first coupling element 246. The lower mounting portion 238 includes a hole 239 to receive the pivot element 284 (see FIG. 3F). Pivot element 284 extends through hole 239 and opening 247a of a second coupling element 247. Each of the coupling elements 246, 247 includes a proximal locking portion 246b, 247b configured to be accommodated in notches 290 formed in the distal end of an inner housing that is formed from the upper and lower housing halves 250 and 252. . Coupling elements 246, 247 retain mounting assembly 235 and upper and lower housing halves 250 and 252 in a longitudinally fixed position relative to each other while allowing pivotal movement of mounting assembly 235 relative thereto.

Referring to Figures 3A-3C, each coupling element 246, 247 includes a cantilevered spring arm 246c having a distal end 246d positioned to engage mounting assembly 235. More specifically, the upper mounting portion 236 includes an upper surface 236a that includes a recess 236b dimensioned to receive the distal end 246d of the spring arm 246c of a respective coupling element 246. The lower mounting portion 238 includes a lower surface 238a having a pair of raised surfaces 238b defining a recess 238c that is dimensioned to receive the spring arm 247c of a respective coupling element 247. Alternatively, at least one recess may be formed in the proximal end of the tool assembly 17.

As illustrated in Figures 3D-3G, when the distal end of the spring arms 246c, 247c of the coupling elements 246, 247 is positioned in the recesses 236b and 238c of the upper and lower mounting portions 236 and 238 , respectively, spring arms 246c, 247c retain mounting assembly 235 in a non-articulated position. The spring arms 246c, 247c will retain the mounting assembly 235 in its unarticulated position until a predetermined force sufficient to bias the spring arms 246c from the recesses 236b and 238c is applied to effect the articulation of the mounting assembly 235 and the tool set 17. When the predetermined force is applied to mounting assembly 235 and tool assembly 17, spring arms 246c, 247c will deform or deflect out of recesses 236b and 238c, as shown in Figures 3E and 3G, to allow pivotal movement of mounting assembly 235 (and thus tool assembly 17) relative to the distal end of DLU 16 proximal body portion 200.

As discussed above, spring arms 246c and recesses 236b and 238c hold tool assembly 17 in its non-hinged position until a predetermined force has been applied to mounting assembly 235 to disengage spring arms 246c, 247c. of recesses 236b and 238c of mounting assembly 235. It is envisioned that the spring arms / recesses can be incorporated into any hinged surgical device including staples, gripping elements (see Figure 3H), mechanical sealing devices, eg, RF sealing devices, etc. Also, although two spring arms / recesses are shown, a single spring arm may be provided. Furthermore, the articulated tool assembly need not be part of a DLU but may instead be supported directly on the distal end of a surgical instrument. For example, the set of mon5

ES 2 392 797 T3 can be detachably or non-detachably secured to the tool assembly and secured directly to the distal end of a surgical instrument.

The upper housing half 250 and lower housing half 252 are contained within an outer sleeve 251 of the body portion 200 (FIG. 3). The body portion 200 includes a cutout 251a dimensioned to accommodate a shoulder 250a formed in the upper housing half 250. Arrangement of shoulder 250a within cutout 251a prevents axial and rotational movement of upper and lower housing halves 250 and 252 within the sleeve.

251 exterior of body part 200. In one embodiment, the protrusion 250a has a substantially rectangular configuration that has an axial dimension greater than the lateral dimension. The larger axial dimension provides a greater surface area to prevent rotation of the upper and lower housing halves 250 and 252 within the sleeve 251. A proximal portion 250b of the boss 250a is sloped. Sloping proximal portion 250b allows sleeve 251 to slide over shoulder 250a as upper and lower housing halves 250 and 252 are positioned within sleeve 253. It is envisaged that shoulder 250a may take other configurations, for example , circular, square, triangular, etc., and also fulfill the function for which it is intended. In addition, the projection 250a can be relocated anywhere along the upper housing half 250 or, alternatively, located in the middle

252 lower housing or partially in each housing half 250 and 252.

The proximal end or insertion tip 193 of the upper housing half 250 includes latching buttons 254 for releasably engaging the distal end of a bayonet-like surgical instrument (see Figures 1A and 7). Housing halves 250 and 252 define a channel 400 for slidably receiving axial drive assembly 212 therein. An articulation link 256 is dimensioned to slidably locate within a slot 402 formed between the upper and lower housing halves 250 and 252. A pair of H-block assemblies 255 are located adjacent to the distal end of housing portion 200 and adjacent to the distal end of axial drive assembly 212 to prevent buckling and outward sagging of drive assembly 212 during articulation and firing of the surgical stapling apparatus 10. Each H-block assembly 255 includes a flexible body 255a that includes a proximal end fixedly secured to body portion 200 and a distal end fixedly secured to mounting assembly 235 (FIG. 3).

A retainer 288 is supported in the engagement section 270 of the axial drive assembly 212. Retainer 288 includes a pair of fingers 288a that are releasably located within slots or recesses 252a formed in the lower housing half 252. In operation, when the SULU 16 is attached to a surgical instrument and the axial drive assembly 212 is actuated by applying a predetermined force to a drive element 516 of the surgical instrument 500 (FIG. 11), the axial drive assembly 212 is advanced distally. to move drive assembly 212 and retainer 288 distally. As the retainer 288 is advanced distally, the fingers 288a are forced relative to the recesses 252a to provide an audible and tactile indication that the surgical instrument has been actuated. The retainer 288 is designed to prevent inadvertent partial actuation of the DLU 16, such as during shipping, by holding the axial actuation assembly 212 in a fixed position within the DLU 16 until a predetermined axial force has been applied to the axial drive assembly 212.

The axial drive assembly 212 includes an elongated drive beam 266 that includes a distal working head 268 and a proximal engagement section 270. In one embodiment, drive beam 266 is constructed from multiple stacked sheets of material. Latch section 270 includes a pair of resilient latch fingers 270a and 270b that engage for mounting with a pair of corresponding detent grooves formed in actuator 272. Actuator 272 includes a proximal hole 274 configured to accommodate the distal end of a control rod 520 (FIG. 11) of a surgical instrument when the proximal end of the DLU 16 engages with the body portion 512 of an instrument 500. surgical.

Referring also to Figures 5-10, the DLU 16 further includes a locking mechanism that includes a locking member 300 and a locking member actuator 302. The locking element 300 (FIG. 6) is rotatably supported within a longitudinal or axial slot 310 (FIG. 7) formed in a proximal portion of the upper housing half 250 of the DLU 16 body portion 200. The blocking element 300 is movable from a first position (Figures 7 and 8), in which the blocking element 300 maintains the actuation assembly 212 in a pre-firing position, to a second position (Figures 9 and 10), in which the drive assembly 212 can move axially freely.

As illustrated in FIG. 6, the locking element 300 includes the semi-cylindrical body 312 that is slidably positioned within the transverse groove 310 formed in the upper housing half 250 of the body portion 200. Body 312 includes a radially inwardly extending cam member 314 and a radially inwardly extending finger 316. Finger 316 is dimensioned to slideably accommodate within a notch or slot 270c (FIG. 3) formed in drive assembly 212. Engagement of finger 316 in notch 270c of actuator assembly 212 prevents actuator assembly 212 from moving linearly within body portion 200 and thus prevents actuation of DLU 16.

Referring to Figures 3, 5 and 7, a locking element actuator 302 is slidably positioned within an axial slot 320 (Figure 7) formed in the upper housing half 250 of the DLU body portion 200. 16.

ES 2 392 797 T3

Actuator 302 includes a proximal stop member 322, a distal spring guide 324, and a central cam slot 326. Axial slot 320 intersects transverse slot 310 such that cam member 314 of lock member 300 is slidably positioned within cam slot 326 of lock member actuator 302. A biasing member or spring 328 (FIG. 7) is positioned around spring guide 324 between a distal surface 330 of actuator 302 and a wall 332 (FIG. 7) defining the distal end of axial slot 320. Spring 328 urges actuator 302 to its retracted position within axial slot 320. In its retracted position, the abutment member 322 is positioned at and extends radially outward from the proximal end of the DLU 16 adjacent the insertion tip 193 of the proximal body portion 200 and the cam slot 326 is positioned to locate cam member 314 such that finger 316 of locking member 300 is positioned within notch 270c of drive assembly 212.

Figures 11-15 illustrate DLU 16 and surgical instrument 500 prior to and during attachment of DLU 16 to surgical instrument 500. Prior to attachment of DLU 16 to surgical instrument 500, spring 328 biases actuator 302 to its retracted position to move locking element 300 to its locked position as discussed above. When the insertion tip 193 of the DLU 16 is linearly inserted into the open end 522 (FIG. 11) of the body portion 512 (FIG. 13) of a surgical instrument 500, the buttons 254 move linearly through the slots ( not shown) formed in the open end 522 of the body portion 512. As buttons 254 pass through the slots, the proximal end 322a of stop member 322, which is angularly offset from buttons 254, abuts a wall 276c that defines the slots for housing buttons 254. A As the DLU 16 moves further into the body portion 512, the locking member actuator 302 moves from its retracted position to its advanced position in the direction indicated by arrow "T" in FIG.

14. As actuator 302 is moved to its advanced position, locking member 300 is cam actuated in the direction indicated by arrow "U" in FIG. 14 from its locked position (FIG. 8) engaged with assembly 212. actuation to its unlocked position (FIG. 10) to move finger 316 relative to notch 270c. The locking mechanism including the locking member 300 and the locking member actuator 302 prevents accidental or inadvertent advancement or manipulation of the DLU 16 actuator such as during loading of the DLU 16 into the surgical instrument 500 .

When the DLU 16 has been moved linearly relative to the instrument 500 to a position where a proximal surface 530 of the body portion 200 abuts the inner surface 276c of the body portion 512 (FIG. 15), the DLU 16 can be rotated relative to the body portion 512 in a bayonet-type action to position the buttons 254 within the openings 536 of the body portion 512 to lock the DLU 16 in the body portion 512. It is envisioned that other types of coupling in addition to bayonet couplings may be used to connect the DLU 16 to the instrument 500, for example, spring pawl or snap coupling, friction fit couplings, locking elements, threaded couplings, etc.

In one embodiment of the present disclosure illustrated in Figures 16-20, a locking assembly 600 for use with the surgical instrument 500 and disposable loading unit 16 is illustrated (see Figure 1, for example). In the illustrated embodiments, the locking assembly 600 includes a housing 602, a pusher 604, a rod 606, a slide guide 608, at least one spring 610, a cam finger 612, a pivot plate 614 having grooves 616 and a 618 link. The locking assembly 600 generally assists the tool assembly 17 (see FIG. 1, for example) in maintaining its position during firing of the surgical instrument 500.

Referring to Figures 16 and 17, a portion of the lock assembly 600 is at least partially contained within a housing 602. Figure 16 illustrates the lock assembly 600 disposed relative to the housing 602, while Figure 17 illustrates lock assembly 600 isolated from housing 602. In the illustrated embodiment of Figure 17, pusher 604 is shown with rod 606 extending distally therefrom. Slide 608 extends distally from rod 606 and is in sliding relationship therewith, thereby allowing slide guide 608 to move axially relative to rod 606. Spring 610 or pair of springs (not explicitly shown in this embodiment) distally deflects the slide guide 608 from the rod 606.

Now referring to Figures 18-20, cam finger 612 and pivot plate 614 are illustrated. Cam finger 612 extends distally from slide 608 and pivot plate 614 may be disposed in mounting assembly 235 (see FIG. 3), for example. It is envisioned that the pivot plate 614 may be arranged in or incorporated with a portion of the tool assembly 17. A plurality of slots 616 (five slots 616 are illustrated) are provided in pivot plate 614 and are dimensioned to accept at least a portion of cam finger 612 therein. At different amounts of articulation of the tool assembly 17 (including no substantial articulation) relative to the body portion 512 (see Figure 1, for example), the cam finger 612 is roughly aligned with an individual slot 616 of the pivot plate 614. Figures 18 and 19 illustrate cam finger 612 substantially aligned with a central slot 616a (hidden from view in Figure 19) and Figure 20 illustrates cam finger 612 substantially aligned with a lateral slot 616b.

Link 618, illustrated in Figures 17 and 19, is mechanically engaged with pivot plate 614 and cam finger 612. (In Figure 18, the link has been removed.) Link 618 is illustrated with an opening 620 and a slot 622 (Figure 19). Aperture 620 is in pivotal relationship with a protrusion 624 on pivot plate 614 and slot 622 is slidably engaged with cam finger 612. This relationship allows the articulation of the pivo plate 614

ES 2 392 797 T3 te with respect to the body portion 512 and the longitudinal translation of the slide guide 608 with respect to the pivot plate 614.

In operation, by at least partially actuating the movable handle 516 (see Figure 1, for example), the pusher 604 is forced distally, for example, through the control rod 520 (see Figure 11, for example), thereby causing distal translation of cam finger 612 at least partially into a slot 616 of pivot plate 614. It is envisioned that actuation of movable handle 516 to approximate cartridge assembly 18 and anvil assembly 20 (see FIG. 1A, for example) also functions to translate cam finger 612 distally. In such an embodiment, when the articulated tool assembly 17 is in place and secured in the tissue, no further articulation can be achieved (without releasing the movable handle 516, for example). Thus, the locking assembly 600 helps to hold the hinged tool assembly 17 in position relative to the body portion 512, prior to placing the staples in tissue, for example.

As discussed above, spring 610 distally biases slide 608 from rod 606. This bias provided by spring 610 helps ensure that cam finger 612 does not accidentally or prematurely dislodge from slot 616 in plate 614. pivot, which can result in a significant amount of "play" between them. In addition, the distal deflection provided by spring 610 helps eliminate manufacturing tolerances and / or clearances between slide 608 and pivot plate 614. It is also envisioned that at least a portion of the cam finger 612 and / or slot 616 may be wedge-shaped to help reduce any inadvertent movement therebetween. In such an embodiment, a distal portion of cam finger 612 and slot 616 would be narrower than a corresponding proximal portion.

In one embodiment of the present disclosure illustrated in Figures 21 and 22, a locking assembly 700 for use with the surgical instrument 500 and disposable loading unit 16 is illustrated (see Figure 1, for example). In the illustrated embodiment, the lock assembly 700 includes an adapter 702, a pusher 704, a pivot 706, a biasing member (eg, a pair of springs 708), and a link 710. The lock assembly 700 generally helps to hold the tool assembly 17 in a predetermined position.

Referring to FIG. 21, the adapter 702 of the locking assembly 700 is generally housed within the body portion 512 (see FIG. 1, for example) of the surgical instrument 500 or within the disposable loading unit 16. In the illustrated embodiment, pusher 704 is located distally of a pair of springs 708. Pusher 704 biases distally through pair of springs 708 toward pivot 706 of articulated tool assembly 17. A distal portion of pusher 704 includes a pusher engaging surface 712 (FIG. 22) that is shaped and dimensioned to mate with a pivot engaging surface 714 (FIG. 22) disposed adjacent a proximal portion of pivot 706. Link 710 is illustrated acting in conjunction mechanically with a portion of pusher 704 and pivotally connected to a portion of pivot 706, thereby allowing articulated tool assembly 17 to move between its first position and its second position with respect to to body part 512. More specifically, link 710 includes an opening 711 that fits over a boss 707 of pivot 706, thereby allowing pivotal movement therebetween. Furthermore, link 710 slidably engages with a portion of adapter 702, thereby allowing longitudinal movement therebetween.

Now referring to FIG. 22, pusher engagement surface 712 is substantially flat along a major portion of its length in this embodiment. Correspondingly, the pivot engaging surface 714 is also flat along a major portion of its length in the illustrated embodiment. Thus, distal deflection of pusher 704 toward pivot 706 (in the direction of arrow A) through pair of springs 708 helps to maintain articulated tool assembly 17 in its first, non-articulated position, since the deflection force assists articulated tool assembly 17 to resist pivoting. Although two springs 708 are illustrated, more or fewer springs 708 may be provided.

To pivot the articulated tool 17 from its first, non-articulated position, the distal bias force from the pair of springs 708 must be overcome. Such a pivoting action moves the pusher 704 proximally (in the direction of the arrow). B) against spring pair deflection 708. The pusher engagement surface 714 is also envisioned to include pawls (not explicitly shown in this embodiment) to help stabilize the articulated jaw member 17 in selected articulated positions.

Still referring to Figure 22, pivot 706 includes a shelf 716 therein. As shown in FIG. 22, shelf 716 overlaps at least a portion of pusher 704 when pusher engaging surface 712 is in contact with pivot engaging surface 714. The shelf 716 is positioned and configured to help avoid pinching the tissue between the pusher 704 and the pivot 706 when the articulated tool assembly 17 is rotated and / or articulated.

In one embodiment of the present disclosure illustrated in Figures 23-25, a multilayer drive beam 750 is illustrated having a plurality of layers 750a-750e and may be included in a disposable loading unit 16 (see Figure 1, for instance). A closure apparatus 760, such as an I-beam, is also illustrated. The closure apparatus 760 includes a horizontal portion 762 that can be advanced toward the camming surface 42 (or other su

ES 2 392 797 T3 contact surface) to approximate the tool assembly 17, as described in detail above with reference to FIG. 2.

Referring to FIG. 24, the multilayer drive beam 750 having five layers 750a 750c is illustrated. It is envisioned and within the scope of the present disclosure that fewer or more layers may be used to form the multilayer drive beam 750. It is also envisioned that the multilayer drive beam 750 may replace the drive beam 266 in other embodiments of this disclosure. The use of the multilayer drive beam 750 can provide increased strength and flexibility during use, specifically, for example, while the tool assembly 17 is in an articulated position.

A plurality of cuts 770 are illustrated in Figures 23-25 ​​extending through each layer of the multilayer drive beam 750. Although the figures show between five and ten cuts per layer of the multilayer drive beam 750, the exact number of cuts 770 may be less than five, between five and ten, or greater than ten. In addition, the cuts 770 of adjacent layers of the drive beam 750 may or may not be aligned with each other. The use of the cuts 770 reduces the cross-sectional dimensions of the drive beam 750 and allows the bending force to be adjusted. Although rectangular cuts 770 are illustrated, the use of cuts 770 with other regular or non-regular shapes is also contemplated.

The attachment of each layer 750a -750e of the multilayer drive beam 750 and the attachment of the closure apparatus 760 is illustrated in Figure 25. In the illustrated embodiment, an outer layer (750a or 750e of Figure 24) is attaches to the closure apparatus 760 at two locations (each location being indicated by number 780 in FIG. 25), through a pair of spot welds, for example. Each outer layer 750a, 750e is also envisioned to include an opening 776 that fits over a protrusion 778 protruding from the closure apparatus 760. Each outer layer 750a, 750e is also attached to an adjacent layer (eg, 750b or 750d) at two locations (each location being indicated by 781 in Figure 25), possibly through a pair of spot welds. Additionally, each inner layer (e.g. 750b, 750e, and 750d) is bonded to an adjacent inner layer (e.g. 750b is bonded to 750c; 750c is bonded to 750b and 750d; and 750d is bonded to 750c) at two locations. , through spot welding, for example. Although spot welding is disclosed as a method of joining, other methods of joining each layer to each other and the outer layers to the closure apparatus are envisaged and are within the scope of the present disclosure. The illustrated embodiments show interior layer attachment points 780 adjacent to closure apparatus 760, but it is envisioned and within the scope of the present disclosure that attachment points 780 are disposed at other locations on drive beam 750. Furthermore, it is envisaged that at least one layer of the drive beam 750 is made of a metal, such as stainless steel. Parts of the drive beam 750 and / or the closure apparatus 760 may also be made of or at least partially lined with a plastic material, as described below. In addition, the closure apparatus 790 may include a cutting surface 766 (FIG. 23) therein for cutting tissue.

In one embodiment of the present invention illustrated in Figures 26 and 27, a closure apparatus 800 and a portion of drive beam 802 are shown. The closure apparatus and / or a contact surface (eg, camming surface 42) of tool assembly 17 (see Figure 2, for example) may include a plastic surface or plastic liner. In this embodiment, the closure apparatus 800 is illustrated with a pair of caps 804 that at least partially cover the horizontal portions 806 of the closure apparatus 800. The caps 804 are made of plastic in this embodiment. Such plastic surfaces disposed on the closure apparatus 800 and / or on the mating surface of the tool assembly 17 generally reduce the amount of friction between them relative to two metal surfaces. That is, an interaction between plastic and metal or between plastic and plastic can create less friction than the interaction between a pair of metal surfaces. This reduced amount of friction can correspond to a reduced firing force.

A portion of the closure apparatus 800, such as the pair of caps 804, is envisioned to be made of plastic, overmoulded with plastic, or includes a plastic liner. Furthermore, a contact surface of the tool assembly 17, or at least a part thereof, may also be made of plastic, overmoulded with plastic, or include a plastic coating.

In one embodiment of the disclosure, the closure apparatus 800 may include an I-shaped cross section, as illustrated in Figures 26 and 27. In addition, the closure apparatus 800 and actuation beam 802 may be part of a disposable loading unit 16 and / or part of a hinged surgical instrument 500. In addition, the drive beam 802 may include a single layer or a plurality of layers (as shown in FIG. 26) and at least a portion of the drive beam 802 may be made of plastic. Still further, the closure apparatus 800 may include a cutting surface 808 (FIG. 27) therein for cutting tissue.

Still referring to Figures 26 and 27, the plastic cap 804 includes a reinforced section 810 that may increase the strength of the closure apparatus 800 or may provide a stronger connection between the cap 804 and the horizontal portion 806 of the fastener apparatus 800. closing. It is also envisioned that the lid 804 can be removably attached to the closure apparatus 800. In such an embodiment, cap 804 can be removed and replaced if any substantial wear or damage occurs.

ES 2 392 797 T3

In one embodiment of the present disclosure illustrated in Figures 28 and 29, a tool assembly 850 is illustrated. The tool assembly 850 of this embodiment includes a channel 852, a first link 860, a second link 870, an anvil assembly 80, a first link rod 890, and a second link rod 892. The first and second tie rods 890, 892 provide a strong connection that makes it easier for the elements of the tool assembly 850 to stay together.

Channel 852 includes an opening 854 (two openings are illustrated) adjacent its proximal end and first attachment member 860 includes a boss 862 (two bosses are illustrated) extending therefrom. Channel 852 can be connected to the first link member by locating opening (s) 854 over shoulder (s) 862, thus providing a pivotal connection between them. Although not explicitly illustrated in the present embodiment, channel 852 can house a plurality of surgical fasteners or a staple cartridge.

Anvil assembly 880 includes an anvil cover 882 and anvil 886. Anvil 886 is configured for mechanical engagement with anvil cover 882, for example, through a snap connection. An opening 884 extends at least partially through a portion of the anvil cover 882. An opening 884 is configured to fit over a protrusion 872 provided in the second link 870, thereby providing a connection between the anvil assembly 880 and the second link 870. Additionally, the anvil cover 882 includes at least one opening 888 that extends at least partially therethrough in one embodiment of the disclosure. Aperture 888 is configured to fit over shoulder 862 of first link 860. In such an embodiment, the anvil assembly 880 can be pivoted relative to the first link 860 and the second link 870.

The first attachment member 860 includes a first opening 864 and a second opening 866 extending therethrough. The second attachment member 870 also includes a first aperture 874 and a second aperture 876 extending therethrough (FIG. 29). In addition, the first link 860 and the second link 870 are mechanically engaged such that the first openings 864, 874 are substantially aligned and the second openings 866, 876 are substantially aligned.

To secure the first link 860 with the second link 870 (and thus the channel 852 and anvil assembly 880), the first link rod 890, or a portion thereof, is inserted through the first openings 864 and 874. To further secure the elements of the tool assembly 850, the second tie rod 892, or a portion thereof, is inserted through the second openings 866 and 876. The first tie rod 890 and / or the second tie rod 892 are envisioned to be rivets, such as two-part rivets that can be tensioned.

In one embodiment of the description, the tool assembly 850 is part of a disposable loading unit, which can be hinged. Articulation of the tool assembly 850 may be facilitated by pivotally attaching the tool assembly 850 to a body portion of a surgical instrument through the protrusion 874 extending from the second attachment member 870 and a link (such as the link 710 in figure 21). In addition, the present disclosure contemplates a method of assembling the tool assembly 850, as described above.

It will be understood that various modifications can be made to the embodiments disclosed herein. For example, the locking assembly described above can be incorporated into a variety of surgical instruments including DLUs and is not limited to use in linear staplers. In addition, the DLU may be configured to accommodate a surgical instrument insertion tip unlike the one disclosed. Therefore, the above description should not be construed as limiting, but merely as examples of various embodiments.