WO2025191440A1

WO2025191440A1 - Surgical stapling device with tissue gap control

Info

Publication number: WO2025191440A1
Application number: PCT/IB2025/052535
Authority: WO
Inventors: Justin P. WILLIAMS; Andrew M. Miesse; Brian L. HOLDEN; Christopher K. EVANS; John W. Beardsley
Original assignee: Covidien LP
Current assignee: Covidien LP
Priority date: 2024-03-15
Filing date: 2025-03-10
Publication date: 2025-09-18
Anticipated expiration: 2026-09-15

Abstract

A surgical stapling device includes a tool assembly and a drive assembly. The tool assembly includes an anvil and a cartridge assembly having a channel member and a staple cartridge. The drive assembly includes a working member assembly having a first beam that is engaged with the anvil and a second beam that is engaged with the cartridge assembly to control the spacing between the anvil and the staple cartridge in the clamped position. The spacing between the first beam and the second beam of the drive assembly is adjustable depending on the thickness of tissue being treated to change the size of the tissue gap defined between the staple cartridge and the anvil during clamping and firing of the stapling device.

Description

SURGICAL STAPLING DEVICE WITH TISSUE GAP CONTROL

CROSS-REFERENCE TO RELATED APPLICATION(S)

[0001] This application claims priority to U.S. Provisional Patent Application No. 63/565,731, filed March 15, 2024, which is incorporated herein by reference in its entirety.

FIELD

[0002] This disclosure is directed to surgical stapling devices and, more particularly, to surgical stapling devices including a tool assembly with tissue gap control.

BACKGROUND

[0003] Surgical stapling devices for ejecting staples to join tissue or tissue segments in a fast and efficient manner during a variety of surgical procedures are well known. Typically, a surgical stapling device includes a tool assembly having a first jaw that supports a cartridge assembly and a second jaw that supports an anvil. The cartridge assembly includes a staple cartridge that supports staples, and the first and second jaws are mounted together to allow movement of the tool assembly between an open position and a clamped position. In the clamped position, the staple cartridge of the cartridge assembly and the anvil are supported in juxtaposed alignment and include tissue contact surfaces that define a predetermined tissue gap. The predetermined tissue gap and the staples are dimensioned to receive and suture tissue having a thickness within a predetermined range to affect hemostasis of the tissue. If the tissue positioned between the jaws has a thickness that is outside the predetermined range, i.e., either too thick or too thin, the stapling device may not provide effective hemostasis.

[0004] Accordingly, a continuing need exists in the suturing arts for a surgical stapling device that can provide effective hemostasis for a greater range of tissue thicknesses.

SUMMARY

[0005] This disclosure is directed to a surgical stapling device that includes a tool assembly and a drive assembly that has a working member assembly with a first beam, a second beam, and a vertical strut that interconnects the first beam and the second beam. The spacing between the first beam and the second beam is adjustable to change a tissue gap defined by the tool assembly. [0006] One aspect of the disclosure is directed to a stapling device including a tool assembly and a drive assembly. The tool assembly includes an anvil and a cartridge assembly. The anvil has a first tissue engaging surface and defines a knife slot that extends through the first tissue engaging surface. The cartridge assembly is coupled to the anvil to facilitate movement of the tool assembly between an open position and a clamped position and includes a channel member and a staple cartridge. The staple cartridge has a second tissue engaging surface that is spaced from the first tissue engaging surface in the clamped position to define a tissue gap. The drive assembly includes a flexible drive beam and a working member assembly. The flexible drive beam defines a longitudinal axis and has a proximal portion and a distal portion. The working member assembly is secured to the flexible drive beam and includes a first upper beam, a second upper beam, a lower beam, and a vertical strut. The vertical strut has a first end portion that supports the first upper beam and the second upper beam and a second end portion that supports the lower beam. The first upper beam is supported on one side of the vertical strut and the second upper beam is supported on an opposite side of the vertical strut. The first upper beam defines a first longitudinal axis and is movable between a first position in which the first longitudinal axis defines a first acute angle with the longitudinal axis of the flexible drive beam and a second position in which the first longitudinal axis is substantially parallel to the longitudinal axis of the flexible drive beam. The second upper beam defines a second longitudinal axis and is movable between a first position in which the second longitudinal axis defines an acute angle with the longitudinal axis of the flexible drive beam and a second position in which the second longitudinal axis is substantially parallel to the longitudinal axis of the flexible drive beam. The first upper beam and the second upper beam are positioned to engage one of the anvil or the cartridge assembly and the lower beam is positioned to engage the other of the anvil or the cartridge assembly.

[0007] In aspects of the disclosure, the working member assembly includes a biasing member that is positioned to urge the first upper beam and the second upper beam towards their first positions.

[0008] In some aspects of the disclosure, the first upper beam and the second upper beam are pivotably coupled to the vertical strut by a pivot member. [0009] In certain aspects of the disclosure, the pivot member is received in through bores defined in the vertical strut, the first upper beam, and the second upper beam.

[0010] In aspects of the disclosure, the biasing member includes a torsion spring.

[0011] In some aspects of the disclosure, the torsion spring is positioned within the through bore of the vertical strut.

[0012] In certain aspects of the disclosure, the first upper beam includes a distal end portion and a proximal end portion, the second upper beam includes a distal end portion and a proximal end portion, and the biasing member is positioned to urge the proximal end portion of the first upper beam into engagement with the one of the anvil or the cartridge assembly and to urge the distal end portion of the second upper beam into engagement with the one of the anvil or the cartridge assembly.

[0013] In aspects of the disclosure, the biasing member is positioned to urge the proximal end portion of the first upper beam and the distal end portion of the second upper beam into engagement with the anvil.

[0014] In some aspects of the disclosure, the stapling device includes an adapter assembly having a proximal portion and a distal portion coupled to the tool assembly.

[0015] In certain aspects of the disclosure, the stapling device includes a handle assembly that is coupled to the proximal portion of the adapter assembly.

[0016] Another aspect of the disclosure is directed to a drive assembly for a stapling device that includes a flexible drive beam and a working member assembly. The flexible drive beam defines a longitudinal axis and has a proximal portion and a distal portion. The working member assembly is secured to the flexible drive beam and includes a first upper beam, a second upper beam, a lower beam, and a vertical strut. The vertical strut has a first end portion supporting the first upper beam and the second upper beam and a second end portion supporting the lower beam. The first upper beam is supported on one side of the vertical strut and the second upper beam is supported on an opposite side of the vertical strut. The first upper beam defines a first longitudinal axis and is movable between a first position in which the first longitudinal axis defines a first acute angle with the longitudinal axis of the flexible drive beam and a second position in which the first longitudinal axis is substantially parallel to the longitudinal axis of the flexible drive beam. The second upper beam defines a second longitudinal axis and is movable between a first position in which the second longitudinal axis defines an acute angle with the longitudinal axis of the flexible drive beam and a second position in which the second longitudinal axis is substantially parallel to the longitudinal axis of the flexible drive beam. The first upper beam and the second upper beam are positioned to engage one of the anvil or the cartridge assembly and the lower beam is positioned to engage the other of the anvil or the cartridge assembly.

[0017] Other aspects of the disclosure are directed to a working member assembly including a first upper beam, a second upper beam, a lower beam, and a vertical strut. The vertical strut has a first end portion and a second end portion and a planar upper surface. The second end portion of the vertical strut supports the lower beam, and the first end portion of the vertical strut supports the first upper beam and the second upper beam. The first upper beam is supported on one side of the vertical strut and the second upper beam is supported on an opposite side of the vertical strut. The first upper beam defines a first longitudinal axis and is movable between a first position in which the first longitudinal axis defines a first acute angle with the planar upper surface of the vertical strut and a second position in which the first longitudinal axis is substantially parallel to the planar upper surface of the vertical strut. The second upper beam defines a second longitudinal axis and is movable between a first position in which the second longitudinal axis defines a second acute angle with the planar upper surface of the vertical strut and a second position in which the second longitudinal axis is substantially parallel to the planar upper surface of the vertical strut. The first upper beam and the second upper beam are positioned to engage one of the anvil or the cartridge assembly and the lower beam is positioned to engage the other of the anvil and the cartridge assembly.

[0018] Other aspects of the disclosure will be appreciated from the following description.

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Various aspects of the disclosed stapling device are described herein below with reference to the drawings, wherein:

[0020] FIG. 1 is a side perspective view of a surgical stapling device including aspects of the disclosure with a tool assembly of the surgical stapling device in an open position;

[0021] FIG. 2 is a side perspective view of a distal portion of the stapling device shown in FIG. 1 with the stapling device in a partially fired position; [0022] FIG. 2A is a cross-sectional view taken along section line 2A-2A of FIG. 2;

[0023] FIG. 3 is a side perspective view of a drive assembly of the surgical stapling device shown in FIG. 1 ;

[0024] FIG. 4 is a side view of a distal portion of the drive assembly shown in FIG. 3;

[0025] FIG. 5 is an enlarged view of the indicated area of detail shown in FIG. 3;

[0026] FIG. 6 is a side perspective, exploded view of a working member assembly of the drive assembly shown in FIG. 3;

[0027] FIG. 7 is a cross-sectional view taken along section line 7-7 of FIG. 2 with this tissue clamped within the tool assembly;

[0028] FIG. 8 is an enlarged view of the indicated area of detail shown in FIG. 7;

[0029] FIG. 9 is a cross-sectional view taken along section line 9-9 of FIG. 7;

[0030] FIG. 10 is a cross-sectional view taken along a longitudinal axis of the tool assembly of the surgical stapling device shown in FIG. 1 with the tool assembly in the clamped, partially fired position with thicker tissue clamped within the tool assembly;

[0031] FIG. 11 is a side perspective view of the distal portion of the drive assembly shown in FIG. 3;

[0032] FIG. 12 is an enlarged view of the indicated area of detail shown in FIG. 10;

[0033] FIG. 13 is a cross-sectional view taken along section line 13-13 of FIG. 10;

[0034] FIG. 14 is a side perspective view of the distal portion of an alternate version of the drive assembly shown in FIG. 3;

[0035] FIG. 15 is a cross-sectional view taken along a longitudinal axis of the tool assembly of the surgical stapling device shown in FIG. 1 including the drive assembly shown in FIG. 14 with the tool assembly in the clamped, partially fired position with thin tissue clamped within the tool assembly;

[0036] FIG. 16 is an enlarged view of the indicated area of detail shown in FIG. 15;

[0037] FIG. 17 is a cross-sectional view taken along the longitudinal axis of the tool assembly of the surgical stapling device shown in FIG. 1 including the drive assembly shown in FIG. 14 with the tool assembly in the clamped, partially fired position with thicker tissue clamped within the tool assembly;

[0038] FIG. 18 is an enlarged view of the indicated area of detail shown in FIG. 17; [0039] FIG. 19 is a side perspective view of the distal portion of another alternate version of the drive assembly shown in FIG. 3;

[0040] FIG. 20 is an enlarged, cutaway view of the tool assembly and drive assembly shown in FIG. 19 with the tool assembly in the clamped partially fired position and thin tissue clamped within the tool assembly;

[0041] FIG. 21 is an enlarged, cutaway view of the tool assembly and drive assembly shown in FIG. 19 with the tool assembly in the clamped, partially fired position and thicker tissue clamped within the tool assembly;

[0042] FIG. 22 is side perspective, exploded view of another alternate version of the working member assembly of the drive assembly shown in FIG. 24;

[0043] FIG. 23A is an enlarged, cutaway view of the tool assembly and drive assembly including the working member assembly shown in FIG. 22 with the tool assembly in the clamped, partially fired position and thinner tissue clamped within the tool assembly;

[0044] FIG. 23B is an enlarged, cutaway view of the tool assembly and drive assembly including the working member assembly shown in FIG. 22 with the tool assembly in the clamped, partially fired position and thicker tissue clamped within the tool assembly;

[0045] FIG. 24 is an enlarged, cutaway view of the tool assembly and drive assembly of the stapling device shown in FIG. 1 including another version of the working member assembly with the tool assembly in the clamped, partially fired position and thinner tissue clamped within the tool assembly;

[0046] FIG. 25 is an enlarged, cutaway view of the tool assembly and drive assembly including the working member assembly shown in FIG. 24 with the tool assembly in the clamped, partially fired position and thicker tissue clamped within the tool assembly; and

[0047] FIG. 26 is an enlarged, cutaway view of the tool assembly and drive assembly of the stapling device shown in FIG. 1 including another version of the working member assembly with the tool assembly in the clamped, partially fired position and thinner tissue clamped within the tool assembly.

DETAILED DESCRIPTION

[0048] The disclosed surgical stapling device 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 several views. However, it is to be understood that the disclosed aspects are merely exemplary of the disclosure and may be embodied in various forms. Well-known functions or constructions are not described in detail to avoid obscuring the disclosure in unnecessary detail. Therefore, specific structural and functional details disclosed herein are not to be interpreted as limiting, but merely as a basis for the claims and as a representative basis for teaching one skilled in the art to variously employ the disclosure in virtually any appropriately detailed structure.

[0049] In this description, the term “proximal” is used generally to refer to that portion of the device that is closer to a clinician, while the term “distal” is used generally to refer to that portion of the device that is farther from the clinician. In addition, directional terms such as front, rear, upper, lower, top, bottom, and similar terms are used to assist in understanding the description and are not intended to limit the disclosure.

[0050] The disclosed surgical stapling device includes a drive assembly and a tool assembly including an anvil and a cartridge assembly. The cartridge assembly includes a channel member that defines a cavity, and a staple cartridge that is supported within the cavity of the channel member. The tool assembly is movable in response to movement of the drive assembly from a drive retracted position to a drive clamped position from an open position to a clamped position to define a tissue gap between the staple cartridge and the anvil. The drive assembly includes a working member assembly that includes a first beam that is engaged with the anvil and a second beam that is engaged with the staple cartridge to control the spacing between the anvil and the staple cartridge during clamping and firing of the stapling device. To accommodate a greater range of tissue thicknesses, the spacing between the first beam and the second beam of the drive assembly is adjustable to change the size of the tissue gap defined between the staple cartridge and the anvil during clamping and firing of the stapling device.

[0051] FIG. 1 illustrates a surgical stapling device 10 according to aspects of the disclosure that includes a handle assembly 12, an elongate body or adapter assembly 14, and a tool assembly 16. In aspects of the disclosure, the handle assembly 12 is powered and includes a stationary handgrip 18 and actuation buttons 20. The actuation buttons 20 are operable to actuate various functions of the tool assembly 16 via the adapter assembly 14 including approximation, stapling, and cutting. In certain aspects of the disclosure, the handle assembly 12 supports batteries (not shown) that provide power to the handle assembly 12 to operate the stapling device 10. Although the stapling device 10 is illustrated as a powered stapling device, it is envisioned that the tool assembly 16 described herein is suitable for use with manually powered surgical stapling devices as well as robotically controlled stapling devices.

[0052] The adapter assembly 14 includes a proximal portion 14a and a distal portion 14b. The proximal portion 14a is coupled to the handle assembly 12 and the distal portion 14b supports the tool assembly 16. The tool assembly 16 includes a cartridge assembly 30 and an anvil 32. The cartridge assembly 30 and the anvil 32 are coupled together such that the tool assembly 16 can pivot between an open position (FIG. 1) and a clamped position (FIG. 7). In the clamped position, the anvil 32 and the cartridge assembly 30 are in juxtaposed alignment with each other and define a tissue gap. In aspects of the disclosure, the anvil 32 is stationary in relation to the adapter assembly 14 and the cartridge assembly 30 pivots in relation to the anvil 32 between the open position and the closed position. Alternately, the cartridge assembly 30 can be stationary in relation to the adapter assembly 14 and the anvil 32 can pivot between the open position and the clamped position.

[0053] FIGS. 2-2A illustrate the tool assembly 16 including the cartridge assembly 30 and the anvil 32 in the clamped position. The anvil 32 includes a tissue engaging surface 32a (FIG. 2A) that defines staple forming pockets (not shown) and is in juxtaposed alignment with the cartridge assembly 30 in the clamped position of the tool assembly 16. The anvil 32 includes an anvil plate 33a and a cover 33b that define a channel 33c that extends longitudinally along the length of the anvil 32. The anvil plate 33a defines a knife slot 33d (FIG. 2A).

[0054] The cartridge assembly 30 includes a channel member 34 and a staple cartridge 35. The channel member 34 includes side walls 36 and a bottom wall 38 that define a cavity 34a having an open end spaced from the bottom wall 38 that receives the staple cartridge 35. The bottom wall 38 defines a knife slot 39 and includes an outer surface 119 that defines a recess 38b that is aligned with the knife slot 39 and extends along a substantial portion of the length of the channel member 34 (FIG. 2A). In aspects of the disclosure, the side walls 36 include distal portions that define recesses 36a. The staple cartridge 35 is removably received within the cavity 34a of the channel member 34 to allow for replacement of the staple cartridge 35 after each firing of the stapling device 10 (FIG. 1) to facilitate reuse of the stapling device 10 (FIG. 1).

[0055] The staple cartridge 35 includes a cartridge body 42, staples 44, pushers 46, an actuation sled (not shown), and a staple guard 50. The staple guard 50 (FIG. 2A) is secured to a bottom side of the cartridge body 42 to retain the staples 44, the pushers 46, and the actuation sled 48 within the cartridge body 42. The cartridge body 42 of the staple cartridge 35 is received within the cavity 34a defined by the channel member 34 and includes a tissue engaging surface 52 that is juxtaposed alignment with the tissue engaging surface 32a (FIG. 2A) of the anvil 32 when the tool assembly 16 is in the clamped position to define a tissue gap “Gl” (FIG. 2A). The cartridge body 42 defines a knife slot 54 and a plurality of staple receiving pockets 56 that are arranged in rows on each side of the knife slot 54. The knife slot 54 in the cartridge body 42 is longitudinally aligned with the knife slot 39 in the channel member 34 and with the knife slot 33d in the anvil plate 33a. In certain aspects of the disclosure, the tissue engaging surface 52 of the staple cartridge 40 has a stepped configuration (FIG. 2A) with raised surfaces adjacent the knife slot 54 and lower surfaces positioned outwardly of the knife slot 54 towards the side walls 36 of the channel member 34. Each of the staple receiving pockets 56 receives one of the staples 44 (FIG. 2A) and at least a portion of one of the pushers 46. In some aspects of the disclosure, the staples 44 in the inner rows of staple receiving pockets 56 are shorter in length than the staples 44 in the outer rows of staple receiving pockets 56. The actuation sled (not shown) is movable from a proximal end of the cartridge body 42 towards a distal end of the cartridge body 42 into sequential engagement with the pushers 46 to urge the pushers 46 upwardly towards the anvil 32 and eject the staples 44 from the staple receiving pockets 56 of the cartridge body 42.

[0056] The cartridge body 42 includes side walls 60 (FIG. 2A) that are positioned on opposite sides of the cartridge body 42 and define longitudinal axes that extend in a direction substantially parallel to the direction of the knife slot 54. Each of the side walls 60 of the cartridge body 42 includes or supports an overhang 62 that extends outwardly from the tissue engaging surface 52 of the cartridge body 42. The overhangs 62 are fixedly secured to, or integrally formed with, the side walls 60 of the cartridge body 42 and include support surfaces 64 (FIG. 2A) that are positioned on a lower portion of the overhangs 62. The support surfaces 64 engage upper end surfaces 36b of the side walls 36 of the channel member 34 when the staple cartridge 35 is received within the cavity 34a of the channel member 34 to support the staple cartridge 35 within the cavity 34a of the channel member 34.

[0057] The cartridge body 42 includes projections 69 (FIG. 2) that are received within the recesses 36a formed in the side walls 36 of the channel member 34 to position the staple cartridge 35 within the cavity 34a of the channel member 34 in proper alignment with the anvil 32. In aspects of the disclosure, the projections 69 have ridged outer surfaces that can be gripped by a clinician to facilitate insertion and removal of the staple cartridge 35 into and from the channel member 34.

[0058] FIGS. 2-6 illustrate a drive assembly 90 of the stapling device 10 (FIG. 1). The drive assembly 90 includes a working member assembly 92 and a flexible drive beam 94. The flexible drive beam 94 has a proximal portion 94a that is adapted to be coupled to a drive member of the adapter assembly 14 (FIG. 1) and a distal portion 94b that is fixedly coupled to the working member assembly 92. In aspects of the disclosure, the flexible drive beam 94 is formed from laminated, stacked sheets, although other constructions are envisioned.

[0059] FIGS. 5 and 6 illustrate the working member assembly 92 which includes a vertical strut 96, a lower beam 98, upper beams 100a, 100b, a biasing member 102 (FIG. 6), and a pivot member 104. The vertical strut 96 of the working member assembly 92 is positioned to extend through the knife slot 36b of the channel member 34, the knife slot 54 of the cartridge body 42, and the knife slot 33d of the anvil plate 33a and supports the lower beam 98 and the upper beams 100a, 100b. The lower beam 98 extends transversely from opposite sides of the vertical strut 96 and is positioned to be received within the recess 38b (FIG. 2A) defined in the bottom wall 38 of the channel member 34. In aspects of the disclosure, the lower beam 98 is integrally formed with the vertical strut 96 although other configurations are envisioned. The vertical strut 96 defines a through bore 106 (FIG. 6) that is positioned adjacent to an upper end of the vertical strut 96 and includes a distally facing cutting blade 108 that is formed on or supported by the vertical strut 96. In aspects of the disclosure, the vertical strut 96 includes a planar upper surface 96a.

[0060] The upper beams 100a and 100b are positioned on opposite sides of the vertical strut 96 and define through bores 110a and 110b (FIG. 6). The pivot member 104 extends through the through bore 106 in the vertical strut 96 and the through bores 110a and 110b of the upper beams 100a and 100b to pivotably support the upper beams 100a and 100b on the upper end of the vertical strut 96. Each of the upper beams 100a and 100b includes a planar engagement surface 112a and 112b, respectively, that is positioned to engage an outer surface 118 (FIG. 2 A) of the anvil plate 33a of the anvil 32 within the channel 33c. In aspects of the disclosure, the through bores 110a and 110b are centrally located on the upper beams 100a and 100b such that the upper beams 100a and 100b are pivotable about the pivot member 104 in see-saw fashion from first positions in which longitudinal axes defined by the upper beams 100a and 100b of the working member assembly 92 define acute angles in relation to the longitudinal axis of the anvil 32 to second positions in which the longitudinal axes defined by the upper beams 100a and 100b are substantially parallel to the longitudinal axis of the anvil 32. Each of the upper beams 100a and 100b has a proximal portion 114a and a distal portion 114b. In aspects of the disclosure, the distal end of the upper beam 100a extends above the planar upper surface 96a of the vertical strut 96 when the upper beam 100a is in its first position and the proximal end of the upper beam 100b extends above the planar upper surface 96a of the vertical strut 96 when the upper beam 100a is in its first position.

[0061] The biasing member 102 is positioned about the pivot member 104 and is received within the through bore 106 of the vertical strut 96 to engage the upper beams 100a and 100b. In aspects of the disclosure, the biasing member 102 includes a torsion spring that includes a first spring portion 102a that is engaged with the upper beam 100a at a position distally of the pivot member 104 and a second spring portion 102b that is engaged with a proximal portion of the upper beam 100b at a position proximally of the pivot member 104. Alternately, other biasing member configurations are envisioned. The biasing member 102 is configured and positioned to pivot the upper beam 100a towards its first position with distal portion 114b of the upper beam 100a positioned above the planar upper surface 96a of the vertical strut 96, and to pivot the upper beam 100b towards its first position with proximal portion 114a of the upper beam 100b positioned above the planar upper surface 96a of the vertical strut 96.

[0062] The upper beams 100a and 100b of the working member assembly 92 are received within the channel 33c (FIG. 2A) of the anvil 32 and engage an outer surface 118 (FIG. 2A) of the anvil plate 33a to restrict outward deflection of the anvil 32 when the tool assembly 16 is clamped and fired. The lower beam 98 is engaged with the outer surface 119 (FIG. 2A) of the channel member 34 of the cartridge assembly 30 to restrict outward movement of the cartridge assembly 30 in relation to the anvil 32 when the tool assembly 16 is clamped and fired. In aspects of the disclosure, the proximal portion 114a of the upper beam 100a is urged into engagement with the outer surface 118 of the anvil plate 33a by the biasing member 102 and the distal portion 114b of the upper beam 100b is urged into engagement with the outer surface 118 of the anvil plate 33a by the biasing member 102 to restrict outward deflection of the anvil 32.

[0063] The drive assembly 90 is movable from a drive retracted position to a drive advanced position to move the working member assembly 92 from the proximal portion of the tool assembly 16 to a distal portion of the tool assembly 16. Although not shown, the working member assembly 92 is positioned to engage the actuation sled (not shown) of the cartridge assembly 30 as the drive assembly 90 moves from the drive retracted position towards the drive advanced position to advance the actuation sled (not shown) within the cartridge body 42 and eject the staples 44 from the cartridge body 42.

[0064] FIGS. 7-9 illustrate the tool assembly 16 of the stapling device 10 in a clamped, partially fired position as the stapling device 10 is fired with thin tissue clamped between the anvil 32 and the cartridge assembly 30. When the stapling device 10 (FIG. 1) is fired, the drive assembly 90 is moved from the drive retracted position towards the drive advanced position in the direction of arrow “A” in FIG. 7 to move the upper beams 100a and 100b of the working member assembly 92 through the channel 33c of the anvil 32 and to move the lower beam 98 along the outer surface 119 of the channel member 34. When thin tissue “Tl” (FIG. 9) is clamped between the anvil 32 and the cartridge assembly 30, the biasing member 102 retains the proximal portion 114a of the upper beam 100a and the distal portion 114b of the upper beam 100b engaged with the outer surface 118 of the anvil plate 33a to maintain the position of the anvil 32 in relation to the cartridge assembly 30 and define a tissue gap “Gl” between the tissue engaging surface 52 of the cartridge body 42 and the tissue engaging surface 32a of the anvil 32. [0065] FIGS. 10-13 illustrate the tool assembly 16 of the stapling device 10 in a clamped, partially fired position as the stapling device 10 is fired with thicker tissue “T2” (FIG. 13) clamped between the anvil 32 and the cartridge assembly 30. When the thicker tissue “T2” (FIG. 13) is clamped between the anvil 32 and the cartridge assembly 30 and the stapling device 10 (FIG. 1) is fired, the clamping force is translated through the thicker tissue “T2” to the upper beams 100a and 100b causing the biasing member 102 to deform. As the biasing member 102 deforms, the upper beam 100a rotates about the pivot member 104 in the direction indicated by arrow “B” in FIG. 11 and the upper beam 100b rotates about the pivot member 104 in the direction indicated by arrow “C” in FIG. 11 to move the upper beams 100a and 100b from their first positions towards their second positions. When the upper beams 100a and 100b pivot towards their second positions, the anvil 32 moves upwardly away from the cartridge assembly 30 in the direction indicated by the arrows “D” in FIG. 13 to increase the spacing between the anvil 32 and the staple cartridge 35. In the second positions of the upper beams 100a and 100b, the planar engagement surfaces 112a and 112b of the upper beams 100a and 100b are engaged with the outer surface 118 of the anvil plate 33a of the anvil 32. When the upper beams 100a and 100b rotate or pivot from their first positions towards their second positions, the distance between the tissue engaging surface 52 of the cartridge body 42 and the tissue engaging surface 32a of the anvil 32 increases to define a tissue gap “G2” greater in size than the tissue gap “Gl”.

[0066] FIGS. 14-17 illustrate an alternate version of the drive assembly of the stapling device 10 (FIG. 1) shown generally as drive assembly 200. The drive assembly 200 is like the drive assembly 90 and includes a working member assembly 210 and a flexible drive beam 212. The flexible drive beam 212 has a proximal portion (not shown) that is adapted to be coupled to a drive member of the adapter assembly 14 (FIG. 1) and a distal portion 216 that is fixedly coupled to the working member assembly 210. In aspects of the disclosure, the flexible drive beam 212 is formed from laminated, stacked sheets, although other constructions are envisioned.

[0067] The working member assembly 210 includes a vertical strut 218, a lower beam 220, an upper beam 222, and biasing members 224. The vertical strut 218 of the working member assembly 210 is positioned to extend through the knife slot 36b of the channel member 34, the knife slot 54 of the cartridge body 42, and the knife slot 33d of the anvil plate 33a (FIG. 2B). The lower beam 220 is fixedly supported on one end of the vertical strut 218, and the upper beam 222 is fixedly supported on the other end of the vertical strut 218. The lower beam 220 and the upper beam 222 extend transversely from opposite sides of the vertical strut 218 at a fixed distance from each other. The lower beam 220 is received within the recess 38b (FIG. 2A) defined in the bottom wall 38 of the channel member 34 and includes inner engagement surfaces 220a that engage the outer surface 119 (FIG. 2 A) of the channel member 34 when the stapling device 10 (FIG. 1) is clamped and fired. The upper beam 222 is received within the channel 33c (FIG. 2 A) defined by the anvil 32 and includes inner engagement surfaces 222a (FIG. 16) that engage the outer surface 118 of the anvil plate 33a. In aspects of the disclosure, the lower beam 220 and the upper beam 222 are integrally formed with the vertical strut 218 although other configurations are envisioned. In certain aspects of the disclosure, the vertical strut 218 includes a distally facing cutting blade 223 that is formed on or supported by the vertical strut 218.

[0068] The biasing members 224 are secured to the inner engagement surfaces 220a of the lower beam 220 on opposite sides of the vertical strut 218. In aspects of the disclosure, each of the biasing members 224 include a curved spring member that is secured to the respective inner engagement surface 220a of the lower beam 220 and bows upwardly towards the upper beam 222. In some aspects of the disclosure, the distal end of each of the biasing members 224 is secured to the inner engagement surface 220a and the proximal end of the biasing member 224 is movable in relation to the inner engagement surface 220a to allow the biasing member 224 to deform from a non-deformed curved configuration to a substantially flat deformed configuration. It is envisioned that the proximal ends of the biasing members 224 can be secured to the inner engagement surfaces 220a of the lower beam 220 such that the distal ends of the biasing members 224 can move in relation to the tissue engagement surfaces 220a. It is also envisioned that the biasing members 224 can be secured to inner engagement surfaces 222a of the upper beam 222 or secured to the inner engagement surfaces 220a and 222a of the lower beam 220 and the upper beam 222 of the working member assembly 210.

[0069] FIGS. 15 and 16 illustrate the tool assembly 16 in the clamped, partially fired position with the drive assembly 200 positioned between the drive retracted position and the drive advanced position with thin tissue clamped between the anvil 32 and the cartridge assembly 30. When thin tissue is clamped between the anvil 32 and the cartridge assembly 30 and the drive assembly 200 is advanced from the drive retracted position towards the drive advanced position, the biasing members 224 are engaged with the outer surface 119 of the channel member 34 (FIG. 2A) to push the cartridge assembly 30 upwardly towards the anvil 32 and define a tissue gap “Gl” between the tissue engaging surface 52 of the cartridge body 42 and the tissue engaging surface 32a of the anvil 32.

[0070] FIGS. 17 and 18 illustrate the tool assembly 16 in the clamped, partially fired position with the drive assembly 200 positioned between the drive retracted position and the drive advanced position with thicker tissue clamped between the anvil 32 and the cartridge assembly 30. When thicker tissue is clamped between the anvil 32 and the cartridge assembly 30 and the drive assembly 200 is advanced from the drive retracted position towards the drive advanced position, the clamping force translated from the tissue to the cartridge assembly 30 causes the biasing members 224 which are engaged with the outer surface 119 of the channel member 34 (FIG. 2A) to compress to allow the cartridge assembly 30 to move downwardly in relation to the anvil 32 in the direction of arrow “E” in FIG. 18 to increase the size of the tissue gap “G2” between the tissue engaging surface 52 of the cartridge body 42 and the tissue engaging surface 32a of the anvil 32.

[0071] FIGS. 20 and 21 illustrate an alternate version of the drive assembly 200 of the stapling device 10 (FIG. 1) shown generally as drive assembly 200’. The drive assembly 200’ is like the drive assembly 200 and includes a working member assembly 210’ and a flexible drive beam 212’. The flexible drive beam 212’ has a proximal portion (not shown) that is adapted to be coupled to a drive member of the adapter assembly 14 (FIG. 1) and a distal portion 216’ that is fixedly coupled to the working member assembly 210’. The working member assembly 210’, like the working member assembly 210, includes a vertical strut 218’, a lower beam 220’, an upper beam 222’, and biasing members 224’. The drive assembly 200’ differs from the drive assembly 200 in that the biasing members 224’ are in the form of compressible pads. The compressible pads 224’ function in a manner like the biasing members 224 and compress to allow the cartridge assembly 30 to move downwardly in relation to the anvil 32 in the direction of arrow “F” in FIG. 21 when thick tissue is clamped to allow the size of the tissue gap between the tissue engaging surface 52 of the staple cartridge 35 and the tissue engaging surface 32a of the anvil 32 to change from tissue gap “Gl” to tissue gap “G2”.

[0072] FIGS. 22-23B illustrate another alternate version of the drive assembly of the stapling device 10 (FIG. 1) shown generally as drive assembly 300. The drive assembly 300 is like the drive assemblies 90 and 200 and includes a working member assembly 310 and a flexible drive beam 312. The flexible drive beam 312 has a proximal portion (not shown) that is adapted to be coupled to a drive member of the adapter assembly 14 (FIG. 1) and a distal portion 316 (FIG. 23 A) that is fixedly coupled to the working member assembly 310. In aspects of the disclosure, the flexible drive beam 312 is formed from laminated, stacked sheets, although other constructions are envisioned.

[0073] The working member assembly 312 includes a first clamp member 318, a second clamp member 320, and biasing members 322. The first clamp member 318 includes an upper beam 324 and a vertical strut 326 secured to, or formed with, a first end of the vertical strut 326. The upper beam 324 extends transversely from the vertical strut 326 to opposite sides of the vertical strut 326. The vertical strut 326 defines a cavity 328 and a slot 330 that extends from the cavity 328 through a second end of the vertical strut 326. The cavity 328 has a width that is greater than the width of the slot 330. The vertical strut 326 includes or supports a cutting blade 332 that is positioned between the cavity 328 and the upper beam 324. The second end of the vertical strut 326 includes inner walls 334 positioned on opposite sides of the slot 330 that support the biasing members 322. [0074] The second clamp member 320 includes a strut extension 336 and a lower beam 338 that extends transversely from the strut portion 336 to opposite sides of the strut extension 336. The strut extension 336 supports a connector 340 that extends upwardly from the strut extension 336 and is received within the cavity 328 of the vertical strut 326 such that the strut extension 336 is aligned with the vertical strut 326. In aspects of the disclosure, the connector 340 has a T- shaped configuration and includes a head portion 340a that is movable within the cavity 328 of the vertical strut 326 to move the second clamp member 320 in relation to the first clamp member 318 between a first position and a second position. As the first clamp member 318 moves in relation to the second clamp member 320 from the first position to the second position, the lower beam 338 moves in relation to the upper beam 324. In the first position (FIG. 23 A), the lower beam 338 is spaced closer to the upper beam 324 than in the second position.

[0075] The biasing members 322 are supported within the cavity 328 of the vertical strut 326 between the inner walls 324 of the vertical strut 326 and head portion 340a of the connector 340 to urge the second clamp member 320 towards the first position. In aspects of the disclosure, the biasing members 322 include coil springs although the use of other types of biasing members is envisioned.

[0076] FIG. 23 A illustrates the tool assembly 16 in the clamped, partially fired position with the drive assembly 300 positioned between the drive retracted position and the drive advanced position with thin tissue clamped between the anvil 32 and the cartridge assembly 30. The upper beam 324 is engaged with outer surface 118 of the anvil plate 33a of the anvil 32 and the lower beam 338 is engaged with the outer surface 119 of the cartridge assembly 30 as described above. When thin tissue is clamped between the anvil 32 and the cartridge assembly 30 and the drive assembly 300 is advanced from the drive retracted position towards the drive advanced position, the biasing members 322 remain in their expanded positions such that the second clamp member 320 remains in the first position to define a tissue gap “Gl” between the tissue engaging surface 52 of the staple cartridge 35 and the tissue engaging surface 32a of the anvil 32.

[0077] FIG. 23B illustrates the tool assembly 16 in the clamped, partially fired position with the drive assembly 300 positioned between the drive retracted position and the drive advanced position with thicker tissue clamped between the anvil 32 and the cartridge assembly 30. As described above, the upper beam 324 is engaged with the anvil 32 and the lower beam 338 is engaged with the cartridge assembly 30. When thicker tissue is clamped between the anvil 32 and the cartridge assembly 30 and the drive assembly 300 is advanced from the drive retracted position towards the drive advanced position, the thicker tissue increases the clamping force applied to the cartridge assembly 30 and the biasing members 322 are compressed to allow the second clamp member 320 to move from the first position towards the second position to move the lower beam 338 away from the upper beam 324 in the direction of arrow “G” to increase the size of the tissue gap “G2” between the tissue engaging surface 52 of the cartridge body 42 of the staple cartridge 35 and the tissue engaging surface 32a of the anvil 32.

[0078] FIGS. 24 and 25 illustrate another alternate version of the drive assembly of the stapling device 10 (FIG. 1) shown generally as drive assembly 400. The drive assembly 400 is like the drive assemblies 90, 200, and 300 and includes a working member assembly 410 and a flexible drive beam 412. The flexible drive beam 412 has a proximal portion (not shown) that is adapted to be coupled to a drive member of the adapter assembly 14 (FIG. 1) and a distal portion 413 (FIG. 23 A) that is fixedly coupled to the working member assembly 410. In aspects of the disclosure, the flexible drive beam 412 is formed from laminated, stacked sheets, although other constructions are envisioned.

[0079] The working member assembly 410 includes a vertical strut 414, an upper beam 416, and a lower beam 418. The upper beam 416 is secured to a first end of the vertical strut 414 and the lower beam 418 is secured to a second end of the vertical strut 414. Each of the upper beam 416 and the lower beam 418 extends transversely from the vertical strut 414 to opposite sides of the vertical strut 414. As described above, the upper beam 416 is positioned to engage the outer surface 118 of the anvil plate 33a of the anvil 32 and the lower beam 418 is positioned to engage the outer surface 119 of the cartridge assembly 30 to limit outward movement of the cartridge assembly 30 in relation to the anvil 32 during clamping and firing of the stapling device 10.

[0080] The vertical strut 414 of the working member assembly 410 includes a body 420 and a distally facing cutting blade 422 that is coupled to, or formed integrally with, the body 420. The body 420 defines an elongated slot 424 that extends through the body 420 between the upper beam 416 and the lower beam 418 along a substantial portion of a height of the body 420, an angled proximal wall portion 426, a proximal radiused recess 428 that is contiguous with the angled proximal wall portion 426, and a distal radiused recess 429. In aspects of the disclosure, the proximal radiused recess 428 and the distal radiused recess 429 are positioned adjacent to the lower beam 418. In some aspects of the disclosure, the vertical strut 414 also defines crescent shaped through bores 430 that are positioned adjacent to the upper beam 416 and the lower beam 418. The vertical strut 414 is movable from a non-deformed state in which a leading edge 418a of the lower beam 418 is positioned distally of the leading edge 416a of the upper beam 416 to a deformed state in which the leading edge 418a of the lower beam 418 is longitudinally aligned with the leading edge 416a of the upper beam 416. The distance between the upper beam 416 and the lower beam 418 increases as the vertical strut 414 moves from the non-deformed state to the deformed state.

[0081] FIG. 24 illustrates the tool assembly 16 in the clamped, partially fired position with the drive assembly 400 positioned between the drive retracted position and the drive advanced position with thin tissue clamped between the anvil 32 and the cartridge assembly 30. The upper beam 416 is engaged with outer surface 118 of the anvil plate 33a of the anvil 32 and the lower beam 418 is engaged with the outer surface 119 of the cartridge assembly 30 as described above. When thin tissue is clamped between the anvil 32 and the cartridge assembly 30 and the drive assembly 400 is advanced from the drive retracted position towards the drive advanced position, the vertical strut 414 remains in the non-deformed state with the leading edge 418a lower beam 418 positioned distal of the upper beam 416 to define a tissue gap “Gl” between the tissue engaging surface 52 of the cartridge body 42 and the tissue engaging surface 32a of the anvil 32. [0082] FIG. 25 illustrates the tool assembly 16 in the clamped, partially fired position with the drive assembly 400 positioned between the drive retracted position and the drive advanced position with thicker tissue clamped between the anvil 32 and the cartridge assembly 30. The upper beam 416 is engaged with the anvil 32 and the lower beam 418 is engaged with the cartridge assembly 30 as described above. When thicker tissue is clamped between the anvil 32 and the cartridge assembly 30 and the drive assembly 400 is advanced from the drive retracted position towards the drive advanced position, the thicker tissue increases the clamping force directed to the upper beam 416 and the lower beam 418 and to the vertical strut 414. The increased clamping force on the vertical strut 414 causes the vertical strut 414 to deform in the direction of arrow “H” from the non-deformed state to the deformed state. As the upper beam 416 moves upwardly and distally in relation to the lower beam 418, the cartridge assembly 30 moves in relation to the anvil 32 to increase the tissue gap “G2” defined between the tissue engaging surface 52 of the cartridge body 42 of the staple cartridge 35 and the tissue engaging surface 32a of the anvil 32. The angled proximal wall portion 426, the proximal radiused recess 428, and the distal radiused recess 429 of the vertical strut 414, and when included, the crescent shaped through bores 430, add flexibility to the vertical strut 414 to facilitate deformation of the vertical strut 414.

[0083] FIG. 26 illustrates yet another alternate version of the drive assembly of the stapling device 10 (FIG. 1) shown generally as drive assembly 500. The drive assembly 500 is like the drive assembly 400 and includes a working member assembly 510 and a flexible drive beam (not shown) that is fixedly coupled to the working member assembly 510. The working member assembly 510 includes a vertical strut 514, an upper beam 516, and a lower beam 518. The upper beam 516 is secured to a first end of the vertical strut 514 and the lower beam 518 is secured to a second end of the vertical strut 514. Each of the upper beam 516 and the lower beam 518 extends transversely from the vertical strut 514 to opposite sides of the vertical strut 514. As described above, the upper beam 516 is positioned to engage the anvil 32 and the lower beam 518 is positioned to engage the cartridge assembly 30 to limit outward movement of the cartridge assembly 30 in relation to the anvil 32 during clamping and firing of the stapling device 10.

[0084] The vertical strut 514 of the working member assembly 510 includes a body 520 and a distally facing cutting blade 522 that is coupled to, or formed integrally with, the body 520. The body 520 of the vertical strut 514 includes a bellows portion 530 that is positioned between the upper beam 516 and the lower beam 518. In aspects of the disclosure, the bellows portion 530 is positioned between the cutting blade 522 and the lower beam 518. The vertical strut 414 is movable from a non-deformed state in which the lower beam 518 is spaced from the upper beam 516 a first distance to define a tissue gap “Gl” to a deformed state in which the lower beam 518 is spaced from the upper beam 516 a second greater distance to define a tissue gap “G2”

[0085] Persons skilled in the art will understand that the devices and methods specifically described herein and illustrated in the accompanying drawings are non-limiting exemplary aspects of the disclosure. It is envisioned that the elements and features illustrated or described in connection with one exemplary aspect of the disclosure may be combined with the elements and features of another without departing from the scope of the disclosure. Also, one skilled in the art will appreciate further features and advantages of the disclosure based on the abovedescribed aspects of the disclosure. Accordingly, the disclosure is not to be limited by what has been particularly shown and described, except as indicated by the appended claims. [0086] Aspects of this disclosure may be further described by reference to the following examples:

[0087] Example 1. A stapling device comprising: a tool assembly including: an anvil having a first tissue engaging surface, the anvil defining a knife slot extending through the first tissue engaging surface; and a cartridge assembly coupled to the anvil to facilitate movement of the tool assembly between an open position and a clamped position, the cartridge assembly including a channel member and a staple cartridge, the staple cartridge having a second tissue engaging surface spaced from the first tissue engaging surface in the clamped position to define a tissue gap; and a drive assembly including: a flexible drive beam defining a longitudinal axis and having a proximal portion and a distal portion; and a working member assembly secured to the flexible drive beam, the working member assembly including a first upper beam, a second upper beam, a lower beam, and a vertical strut, the vertical strut having a first end portion supporting the first upper beam and the second upper beam and a second end portion supporting the lower beam, the first upper beam supported on one side of the vertical strut and the second upper beam supported on an opposite side of the vertical strut, the first upper beam defining a first longitudinal axis and being movable between a first position in which the first longitudinal axis defines a first acute angle with the longitudinal axis of the flexible drive beam and a second position in which the first longitudinal axis is substantially parallel to the longitudinal axis of the flexible drive beam, and the second upper beam defining a second longitudinal axis and being movable between a first position in which the second longitudinal axis defines an acute angle with the longitudinal axis of the flexible drive beam and a second position in which the second longitudinal axis is substantially parallel to the longitudinal axis of the flexible drive beam, wherein the first upper beam and the second upper beam are positioned to engage one of the anvil or the cartridge assembly and the lower beam is positioned to engage the other of the anvil or the cartridge assembly.

[0088] Example 2. The stapling device of example 1, wherein the working member assembly includes a biasing member positioned to urge the first upper beam and the second upper beam towards their first positions.

[0089] Example 3. The stapling device of example 2, wherein the first upper beam and the second upper beam are pivotably coupled to the vertical strut by a pivot member. [0090] Example 4. The stapling device of example 3, wherein the pivot member is received in through bores defined in the vertical strut, the first upper beam, and the second upper beam.

[0091] Example 5. The stapling device of example 4, wherein the biasing member includes a torsion spring.

[0092] Example 6. The stapling device of example 5, wherein the torsion spring is positioned within the through bore of the vertical strut.

[0093] Example 7. The stapling device of example 4, wherein the first upper beam includes a distal end portion and a proximal end portion, and the second upper beam includes a distal end portion and a proximal end portion, the biasing member positioned to urge the proximal end portion of the first upper beam into engagement with the one of the anvil or the cartridge assembly and to urge the distal end portion of the second upper beam into engagement with the one of the anvil or the cartridge assembly.

[0094] Example 8. The stapling device of example 7, wherein the biasing member is positioned to urge the proximal end portion of the first upper beam and the distal end portion of the second upper beam into engagement with the anvil.

[0095] Example 9. The stapling device of example 1, further including an adapter assembly having a proximal portion and a distal portion, the distal portion of the adapter assembly coupled to the tool assembly.

[0096] Example 10. The stapling device of example 9, further including a handle assembly coupled to the proximal portion of the adapter assembly.

[0097] Example 11. A drive assembly for a surgical stapling device, the drive assembly comprising: a flexible drive beam defining a longitudinal axis and having a proximal portion and a distal portion; and a working member assembly secured to the flexible drive beam, the working member assembly including a first upper beam, a second upper beam, a lower beam, and a vertical strut, the vertical strut having a first end portion supporting the first upper beam and the second upper beam and a second end portion supporting the lower beam, the first upper beam supported on one side of the vertical strut and the second upper beam supported on an opposite side of the vertical strut, the first upper beam defining a first longitudinal axis and being movable between a first position in which the first longitudinal axis defines a first acute angle with the longitudinal axis of the flexible drive beam and a second position in which the first longitudinal axis is substantially parallel to the longitudinal axis of the flexible drive beam, and the second upper beam defining a second longitudinal axis and being movable between a first position in which the second longitudinal axis defines an acute angle with the longitudinal axis of the flexible drive beam and a second position in which the second longitudinal axis is substantially parallel to the longitudinal axis of the flexible drive beam, wherein the first upper beam and the second upper beam are positioned to engage one of the anvil or the cartridge assembly and the lower beam is positioned to engage the other of the anvil or the cartridge assembly.

[0098] Example 12. The drive assembly of example 11 , wherein the working member assembly includes a biasing member positioned to urge the first upper beam and the second upper beam towards their first positions.

[0099] Example 13. The drive assembly of example 12, wherein the first upper beam and the second upper beam are pivotably coupled to the vertical strut by a pivot member.

[00100] Example 14. The drive assembly of example 13, wherein the pivot member is received in through bores defined in the vertical strut, the first upper beam, and the second upper beam.

[00101] Example 15. The drive assembly of example 14, wherein the biasing member includes a torsion spring.

[00102] Example 16. The drive assembly of example 15, wherein the torsion spring is positioned within the through bore of the vertical strut.

[00103] Example 17. The drive assembly of example 12, wherein the first upper beam includes a distal end portion and a proximal end portion, and the second upper beam includes a distal end portion and a proximal end portion, the biasing member positioned to urge the proximal end portion of the first upper beam downwardly and to urge the distal end portion of the second upper beam downwardly.

[00104] Example 18. A working member assembly comprising: a first upper beam; a second upper beam; a lower beam; and a vertical strut having a first end portion and a second end portion and a planar upper surface, the second end portion of the vertical strut supporting the lower beam and the first end portion of the vertical strut supporting the first upper beam and the second upper beam, the first upper beam supported on one side of the vertical strut and the second upper beam supported on an opposite side of the vertical strut, the first upper beam defining a first longitudinal axis and being movable between a first position in which the first longitudinal axis defines a first acute angle with the planar upper surface of the vertical strut and a second position in which the first longitudinal axis is substantially parallel to the planar upper surface of the vertical strut, and the second upper beam defining a second longitudinal axis and movable between a first position in which the second longitudinal axis defines a second acute angle with the planar upper surface of the vertical strut and a second position in which the second longitudinal axis is substantially parallel to the planar upper surface of the vertical strut, wherein the first upper beam and the second upper beam are positioned to engage one of the anvil or the cartridge assembly and the lower beam is positioned to engage the other of the anvil and the cartridge assembly.

[00105] Example 19. The working member assembly of example 18, further comprising a biasing member positioned to urge the first upper beam and the second upper beam towards their first positions.

[00106] Example 20. The working member assembly of example 19, wherein the first upper beam includes a distal end portion and a proximal end portion, and the second upper beam includes a distal end portion and a proximal end portion, the biasing member positioned to urge the proximal end portion of the first upper beam downwardly and to urge the distal end portion of the second upper beam downwardly.

Claims

WHAT IS CLAIMED IS:

1. A stapling device (10) comprising: a tool assembly (16) including: an anvil (32) having a first tissue engaging surface (32a), the anvil (32) defining a knife slot extending through the first tissue engaging surface (32a); and a cartridge assembly (30) coupled to the anvil (32) to facilitate movement of the tool assembly (16) between an open position and a clamped position, the cartridge assembly (30) including a channel member (34) and a staple cartridge (35), the staple cartridge (35) having a second tissue engaging surface (52) spaced from the first tissue engaging surface (32a) in the clamped position to define a tissue gap; and a drive assembly (90) including: a flexible drive beam (94) defining a longitudinal axis and having a proximal portion and a distal portion; and a working member assembly (92) secured to the flexible drive beam (94), the working member assembly (92) including a first upper beam (100a), a second upper beam (100b), a lower beam (98), and a vertical strut (96), the vertical strut (96) having a first end portion supporting the first upper beam (100a) and the second upper beam (100b) and a second end portion supporting the lower beam (98), the first upper beam (100a) supported on one side of the vertical strut (96) and the second upper beam (100b) supported on an opposite side of the vertical strut (96), the first upper beam (100a) defining a first longitudinal axis and being movable between a first position in which the first longitudinal axis defines a first acute angle with the longitudinal axis of the flexible drive beam (94) and a second position in which the first longitudinal axis is substantially parallel to the longitudinal axis of the flexible drive beam (94), and the second upper beam (100b) defining a second longitudinal axis and being movable between a first position in which the second longitudinal axis defines an acute angle with the longitudinal axis of the flexible drive beam (94) and a second position in which the second longitudinal axis is substantially parallel to the longitudinal axis of the flexible drive beam (94), wherein the first upper beam (100a) and the second upper beam (100b) are positioned to engage one of the anvil (32) or the cartridge assembly (30) and the lower beam (98) is positioned to engage the other of the anvil (32) or the cartridge assembly (30).

2. The stapling device (10) according to claim 1, wherein the working member assembly (92) includes a biasing member (102) positioned to urge the first upper beam (100a) and the second upper beam (100b) towards their first positions.

3. The stapling device (10) according to claim 2, wherein the first upper beam (100a) and the second upper beam (100b) are pivotably coupled to the vertical strut (96) by a pivot member (104).

4. The stapling device (10) according to claim 3, wherein the pivot member (104) is received in through bores (110a, 110b) defined in the vertical strut (96), the first upper beam (100a), and the second upper beam (100b).

5. The stapling device (10) according to claim 4, wherein the biasing member (102) includes a torsion spring.

6. The stapling device (10) according to claim 5, wherein the torsion spring (102) is positioned within the through bore of the vertical strut (96).

7. The stapling device (10) according to claim 4, wherein the first upper beam (100a) includes a distal end portion and a proximal end portion, and the second upper beam (100b) includes a distal end portion and a proximal end portion, the biasing member (102) positioned to urge the proximal end portion of the first upper beam (100a) into engagement with the one of the anvil (32) or the cartridge assembly (30) and to urge the distal end portion of the second upper beam (100b) into engagement with the one of the anvil (32) or the cartridge assembly (30).

8. The stapling device (10) according to claim 7, wherein the biasing member (102) is positioned to urge the proximal end portion of the first upper beam (100a) and the distal end portion of the second upper beam (100b) into engagement with the anvil (32).

9. The stapling device (10) according to claim 1, further including an adapter assembly having a proximal portion and a distal portion, the distal portion of the adapter assembly (14) coupled to the tool assembly (16).

10. The stapling device (10) according to claim 9, further including a handle assembly (12) coupled to the proximal portion of the adapter assembly (14).