Abstract:
A surgical stapler has a handle assembly including a stationary handle and a trigger. The stapler also has a drive assembly with a body having a working end and a cam member supported on the working end. The cam member is positioned to translate relative to the anvil to maintain the anvil in the closed position during firing of the stapler. The trigger is operatively connected to a power cell. The power cell is operably connected to a motor of the drive assembly. The manipulation of the trigger actuates the power cell such that the power cell powers the drive assembly to effect translation of the cam member relative to the anvil. The stapler also has a channel for supporting the staple cartridge and the motor of the drive assembly controls the actuation sled supported within the cartridge. The actuation sled urges the plurality of staples from the cartridge when the anvil is in the closed position and in cooperative alignment with the staple cartridge.

Description:
CROSS REFERENCE TO RELATED PATENT APPLICATIONS 
     This patent application claims priority to U.S. Provisional Patent Application Ser. No. 60/687,406 to Viola, et al. filed on Jun. 3, 2005 which is herein incorporated by reference in its entirety. This patent application also claims priority to U.S. Provisional Patent Application Ser. No. 60/687,244 to Viola, et al. filed on Jun. 3, 2005 which is also herein incorporated by reference in its entirety. This application is a continuation of patent application Ser. No. 11/446,283, filed on Jun. 2, 2006, now U.S. Pat. No. 7,461,767. This patent application also relates to U.S. patent application Ser. No. 11/446,282 to Viola, et al., filed contemporaneously with the instant patent application which is herein incorporated by reference in its entirety. 
    
    
     BACKGROUND 
     1. Technical Field 
     The present disclosure relates to surgical instruments. More particularly, the present disclosure relates to a surgical stapling device that has an improved and internally powered driving mechanism. 
     2. Background of the Related Art 
     Surgeons have recognized in the art the benefits of a compact surgical apparatus for the application of surgical clips and staples to body tissue in a number of different medical procedures. Often, prior art surgical staplers require some degree of physical force or lateral movement in order to operate a handle to actuate the surgical stapler and fire the staple after a compression to actuate the surgical stapler and fire the staple after a compression of tissue is made. It would be desirable to have a precise surgical stapler device that is compact and easy to use and will quickly and easily fire. Also, once compression of the desired stapling location is made, only a very limited degree of force to the surgical stapling device should be required in order to complete the actuation of the device and thus firing of the staples such as by actuating a trigger switch. Moreover, such a powered stapling device should be very easy to manipulate and hold by the surgeon. 
     Attempts have been made in the art to provide such a surgical stapling device that is pneumatic or gas powered and/or also externally powered in order to remedy this desire. However, it would be beneficial to provide a disposable apparatus for the application of staples to body tissue that is self contained, self powered and easy to manufacture. 
     SUMMARY 
     According to a first aspect of the present disclosure, there is provided a surgical stapler. The stapler has a handle assembly including a stationary handle and a trigger. The trigger is configured to manipulate a cam member through an actuating stroke. The stapler has an elongated body extending distally from the handle assembly and defining a longitudinal axis with a staple cartridge supported adjacent the distal end of the elongated body and containing a plurality of staples. The stapler has an anvil pivotally mounted in relation to the cartridge adjacent the distal end of the elongated body. The anvil has a fastener forming surface thereon and is mounted for pivotal movement in relation to the cartridge between an open position having a distal end spaced from the staple cartridge and a closed position in close cooperative alignment with the staple cartridge. The stapler has an actuation sled supported within the cartridge. The actuation sled is movable to urge the plurality of staples from the cartridge. The stapler also has a drive assembly with a body having a working end and a cam member supported on the working end. The cam member is positioned to translate relative to the anvil to maintain the anvil in the closed position during firing of the stapler. 
     The trigger is operatively connected to a power cell. The power cell is operably connected to a motor of the drive assembly. The manipulation of the trigger actuates the power cell such that the power cell powers the drive assembly to effect translation of the cam member relative to the anvil. The stapler also has a channel for supporting the staple cartridge and the motor of the drive assembly controls the actuation sled supported within the cartridge. The actuation sled urges the plurality of staples from the cartridge when the anvil is in the closed position and in cooperative alignment with the staple cartridge. 
     According to another aspect of the present disclosure, there is provided a surgical stapler. The stapler has a handle assembly with a stationary handle and a trigger configured to manipulate a cam member through an actuating stroke. The stapler also has an elongated body extending distally from the handle assembly and defining a longitudinal axis. The stapler also has a staple cartridge supported adjacent the distal end of the elongated body and containing a plurality of staples with an anvil pivotally mounted in relation to the cartridge adjacent the distal end of the elongated body. The anvil has a fastener forming surface thereon and is mounted for pivotal movement in relation to the cartridge between an open position having a distal end spaced from the staple cartridge and a closed position in close cooperative alignment with the staple cartridge. 
     The stapler has an actuation sled supported within the cartridge. The actuation sled moves to urge the plurality of staples from the cartridge. The actuation sled is connected to a drive rack. The drive assembly has a body with a working end and a cam member supported on the working end. The cam member is positioned to translate relative to the anvil to maintain the anvil in the closed position during firing of the stapler. 
     The trigger is operatively connected to a power cell. The power cell is operably connected to a motor of the drive assembly such that manipulation of the trigger actuates the power cell such that the power cell powers the drive assembly to effect translation of the cam member relative to the anvil. The stapler also has a channel for supporting the staple cartridge. The motor of the drive assembly controls the actuation sled supported within the cartridge. The actuation sled urges the plurality of staples from the cartridge when the anvil is in the closed position and in cooperative alignment with the staple cartridge. 
     The stapler also has a protective casing. The protecting casing houses the power cell and the motor in the protective casing and is connected to the stationary handle. The motor has a motor drive shaft that extends through the stationary handle to connect with the drive rack. 
     According to another aspect of the present disclosure, the surgical stapler is powered by an inexpensive disposable power source that may be actuated by a manual or automatic switch or switch system and that has a power cell coupled to a motor assembly to assist with actuation and firing of the staples. 
     In another embodiment, the stapler has a power supply that can actuate the stapler and the power source can easily move the drive mechanism to an appropriate position for the next stapling operation. 
     According to another aspect of the present disclosure, there is provided a surgical stapler. The stapler has a handle assembly including a trigger and a clamping device including a staple cartridge with a plurality of staples and an anvil having a fastener forming surface thereon. The stapler also has a controller configured to determine an occurrence of clamping by the anvil and the staple cartridge. The controller controls firing of the plurality of staples from the staple cartridge. When the trigger is actuated the controller delays firing of the plurality of staples from the staple cartridge to provide for a predetermined time period of tissue compression of the tissue between the anvil and staple cartridge. The controller outputs a control signal to allow firing once the predetermined time period is reached. The stapler also has a motor having a geared assembly. The motor is disposed in the handle and configured to receive the control signal from the controller. The motor is operatively connected to the staple cartridge to fire the staples from the staple cartridge once the control signal is received. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       Other and further objects, advantages and features of the present disclosure will be understood by reference to the following specification in conjunction with the accompanying drawings, in which like reference characters denote like elements of structure and: 
         FIG. 1  is a perspective view of a first embodiment of a surgical stapler of the present disclosure; 
         FIG. 1A  is a schematic of the handle portion of the surgical stapler of  FIG. 1  showing the trigger switch and a power cell coupled to a motor; 
         FIG. 2  is an exterior cross sectional view of the surgical stapler along line  2 - 2  of  FIG. 1  with the surgical stapler having a drive compartment thereon; 
         FIG. 3  is an interior cross sectional view of the surgical stapler being opposite the compartment; 
         FIG. 3A  is an exploded view of a channel of the surgical stapler of one embodiment of the stapler; 
         FIG. 3B  is an exploded view of the staple cartridge, anvil and the drive sled of  FIG. 1 ; 
         FIG. 4  is another cross sectional view of another embodiment of the surgical stapler of  FIG. 1  having a drive source in the handle of the surgical stapler; 
         FIG. 4A  illustrates another cross sectional view of the surgical stapler of  FIG. 1  having a bevel geared arrangement; 
         FIG. 5  is a cross sectional view of an endoscopic portion of the surgical stapler of  FIG. 4 ; and 
         FIG. 6  is yet another cross sectional view of another embodiment of the surgical stapler of  FIG. 1  with the drive source being in the handle and geared to the drive screw of the surgical stapler. 
     
    
    
     DETAILED DESCRIPTION 
     In the drawings and in the description which follows, the term “proximal”, as is traditional, will refer to the end of the apparatus which is closest to the operator, while the term “distal” will refer to the end of the apparatus which is furthest from the operator. 
     The present disclosure shall be discussed in terms of both conventional and endoscopic procedures and apparatus. However, use herein of terms such as “endoscopic”, “endoscopically”, and “endoscopic portion”, among others, should not be construed to limit the present disclosure to an apparatus for use only in conjunction with an endoscopic tube. To the contrary, it is believed that the apparatus of present disclosure may find use in procedures in these and other uses including but not limited to where access is limited to a small incision such as arthroscopic and/or laparoscopic procedures, or any other conventional medical procedures known in the art. 
     Referring now to the figures, wherein like reference numerals identify similar structural elements of the subject disclosure, there is illustrated in  FIG. 1  a self-contained powered surgical stapler constructed in accordance with one embodiment of the subject disclosure and designated generally by reference numeral  10 . The surgical stapler  10  is a disposable surgical instrument. However, the disposable arrangement is non-limiting and other non-disposable arrangements may be contemplated and are within the scope of the present disclosure. 
     The surgical stapler  10  of the present disclosure shown in a perspective view in  FIG. 1  and described herein includes a frame generally represented by reference numeral  12  and handle generally represented by reference numeral  14 . The frame  12  defines a series of internal chambers or spaces for supporting various mechanical components of the surgical stapler  10  as well as a number of staples therein for the application to the body tissue. 
     The frame  12  supports an endoscopic portion  16  or an extended tube-like portion. The endoscopic portion  16  is capable of being rotated and has a relatively narrow diameter, on the order of in a range that includes about 10 millimeters, and is for insertion into a small opening in or tube inserted into the body, such as in the abdominal cavity, or other similar body cavities. The endoscopic portion  16  has a longitudinal axis and has a length. The length is appropriate for reaching the operation site in the interior of the body. The surgical stapler  10  may be used in conjunction with other instruments such as endoscopes or other such optical devices for visually examining the interior of the body, for example, cameras by means of fiber optics or other optical or recording devices. 
     Generally, the endoscopic portion  16  of the surgical stapler  10  is inserted through the small opening or wound, and is manipulated to the operation site. At the operation site, the surgical stapler  10  is actuated. 
     The endoscopic portion  16  has a fastening assembly  18  and cutting assembly that is known in the art. The fastening assembly  18  and the cutting assembly are located in a housing  20  which carries a fastener and a cutter to the operation site. The fastening assembly  18  in this one non-limiting embodiment has a pair of jaws  21 ,  22 , or an anvil  22  and a staple cartridge  21 . The jaws  21 ,  22  may be a first jaw  21  and second jaw  22  that opens and closes or alternatively another clamping structure for compression of the tissue at the stapling site. The jaws  21 ,  22  are defined by a staple carrying cartridge  21  and the anvil  22  that is located therein. The staple carrying cartridge  21  is in one embodiment located at the distal end of the housing  20 . The staple carrying cartridge  21  has one or a number of rows of staples. The surgical stapler  10  also has an anvil  22  with a forming surface (not shown) and further includes a knife (not shown) as is well known in the art for accomplishing the surgical stapling. 
     Generally, actuating the operating portion of the fastening assembly  18  is accomplished via intermediate components disposed on or within the narrow longitudinally extending tubular endoscopic portion  16 . In one embodiment, a cylindrical tubular sleeve member surrounds the endoscopic portion  16 . The sleeve may be manipulated in a direction with the longitudinal axis of the surgical stapling device. The surgical stapler  10  of the present disclosure has three basic actions or functions. 
     First, the endoscopic portion  16  is introduced into the human or animal body and is positioned with the jaws  21 ,  22  aligned at the desired stapling site to receive the target tissue. This may involve rotation of the endoscopic portion  16  relative to the body, either by rotating the surgical stapler  10 , as a whole, by rotating simply the endoscopic portion  16  relative to the frame  12  as permitted, or a combination of both actions. Thereafter, the surgical stapler  10  secures the target body tissue between the staple cartridge  21  in the distal portion of the housing  20  and the anvil  22 . This is accomplished by a clamping action of the jaws  21 ,  22  or alternatively by another similar or different clamping member. The jaws  21 ,  22  are allowed to remain in the closed position for a period of time. The jaws  21 ,  22  remaining closed for a predetermined period of time allow any excess liquid or fluid in the tissues to drain out of the body tissues prior to actuation of the stapling mechanism. This ensures that the liquid does not rapidly traverse out of the tissues to impede formation of the closed or formed staple and ensures a proper staple formation. 
     With the target tissue clamped between the anvil  22  and the staple cartridge  21 , a camming surface which surrounds the housing  20  and anvil member  22  may be employed to close the jaws  21 ,  22  of the surgical stapler  10  and clamp the tissue between the anvil  22  and the tissue contacting surface of the staple cartridge  21 . The jaws  21 ,  22  may be clamped by actuating or closing lever  24  that is opposite the jaws  21 ,  22 . Thereafter, the third action of the operator or more particularly the surgeon is that of applying the staples to the body tissue. A longitudinally extending channel is employed to deliver longitudinal motion to an axial drive member and a tissue cutting knife. 
     The stapler  10  may have an axial drive member or an axial drive screw to contact a pusher. The pusher elements drive the staples through the body tissue against the fastener or forming surface of the anvil  22 . Typically, in the art the surgical stapler  10  fires usually by an actuation of a first trigger  26 . Thereafter, the clamping action of the jaws  21 ,  22  is released and the surgical stapler  10  or a portion thereof may be withdrawn from the body cavity or site. 
     A known and recognized benefit is that often an operator will desire a surgical stapler  10  that is self-actuating or that actuates with only a limited degree of physical force using the trigger handle (not shown) or using a trigger switch  26 . It is envisioned that surgeons would desire such a surgical stapler  10  that does not have to be connected to any external power supply but instead includes an internal battery operated power supply. Operators would desire a surgical stapler having an internal power source that is comfortable to hold, compact and that is very suitable for endoscopic or laparoscopic procedures as well as other conventional surgical procedures. The stapler  10  of the present disclosure is advantageous since it is a compact and ergonomic member. It is also very advantageous to form such a surgical stapler  10  from few component parts relative to the prior art surgical instruments. This reduces manufacturing costs of the surgical stapler. 
     The present disclosure in one embodiment uses a motor drive source having a substantially offset or a direct drive to remedy these known issues in the art.  FIG. 1A  shows a schematic illustration of an interior of the handle  14 . The surgical stapler  10  in this embodiment is powered by a motor  30 . The trigger switch  26  in this embodiment is connected by lead  27  to a power source  29  such as a battery. The battery  29  is connected by lead  31  to a motor  30 . The motor  30  is connected by lead  31  to the switch  26 . Upon the actuation of switch  26 , power will traverse from the battery  29  to the motor  30 . The energized motor  30  will rotate the motor drive shaft  32  to spin gear  68 . Gear  68  is in contact with gear  70 . Gear  68  rotates second gear  70  which will rotate drive screw  66 . The drive screw  66  upon rotation will move in a longitudinal manner to actuate one or more other components of the surgical stapler  10  such for compression of tissue or stapling. Although, the battery  29  and the motor  30  are shown as being located in the handle  14 , other locations are contemplated. 
     Referring now to  FIG. 2 , there is shown a cross sectional view of the surgical stapler  10  of the present disclosure along line  2 - 2  of  FIG. 1  from a rear view of the surgical stapler of  FIG. 1 . Disposed on an adjacent side of the surgical stapler  10  is shown a protective housing  28 . The protective housing  28  is for housing one or more components of the surgical stapler  10 . The protective housing  28  may be disposed on either adjacent side of the handle  14  or in another position being parallel with the handle. The protective housing  28  is a generally a cylindrical compact member having an interior that is disposed adjacent to, and on a lateral side of the handle  14 . The protective housing  28  is made from a suitable thermoplastic member that is suitable for surgical procedures and has a suitable volume to hold one or more commercially available batteries, or another power source. Although shown as cylindrical, other shapes are possible and the protective housing  28  is not limited to this configuration. The protective housing  28  has the interior space. The space has a compact size and has an advantageous drive source  30  disposed therein. 
     The surgical stapler  10  of the present disclosure may have a first axial drive shaft for operation of the stapling mechanism in the proximal end of the surgical stapler  10  as is known in the art. Such stapling mechanisms are well known in the art and may be found in U.S. Pat. Nos. 6,330,965 B1 to Milliman, et al., 6,250,532 B1 to Green, et al., 6,241,139 B1 to Milliman, et al., 6,109,500 to Alli et al., 6,202,914 B1 to Geiste, et al., 6,032,849 to Mastri, et al. and 5,954,259 to Viola, et al., which are all herein incorporated by reference in their entirety. 
     The drive source  30  has electrical contacts to an integrated power supply and an optional switch system. The drive source  30  is run by any integrated power supply that is compact, and low cost to manufacture. In one embodiment, the drive source  30  also has a suitable amount of torque in order to fire and apply the staple to the body tissue or bone, and form the staple using a forming surface disposed on an anvil. In one embodiment, the drive source  30  is a simple motor assembly having a drive shaft  32 . The motor may be any device that converts the current from the portable power cells into mechanical energy but may be any motor that is low cost and that may be disposable and easily discarded after use. The drive shaft  32  is connected through the handle  14  through a sealed aperture in the handle  14 . Aperture may be sealed using an “O” ring or similar structure to ensure no fluids enter the stapler  10 . 
     Alternatively, the drive source  30  may comprise any electrically powered motor known in the art. The present disclosure provides that the drive source  30  may have a number of modular components that are disposable, permanent, replaceable or interchangeable. In one aspect, the motor  30  may be a modular component and replaceable. In another aspect, the battery can be a modular component and replaceable separate from the drive source  30 . In still another aspect, both the battery and the motor of the drive source  30  may be modular components. The motor and battery may be stored in a casing or be separate units. 
     In one embodiment, the drive source  30  has electrical contacts to, and is powered by, one more internal power cells. The power cells may be one or more disposable or rechargeable power cells. For example, the power cells may be a nickel cadmium type battery, an alkaline battery, a lithium battery, or a nickel metal hydride and may be replaceable or disposable with the entire surgical stapler  10 . Alternatively, the power cells of the drive source  30  may also disengage from the surgical stapler  10  for recharging. Once disconnected, the surgical stapler  10  itself then may be discarded after use. 
     In one embodiment, the one or more power cells of the drive source  30  are disposed and oriented in a generally perpendicular fashion relative to an outer surface of the handle  14  as shown in the housing  28  and optionally may be located in a casing with the motor assembly. In this non-limiting embodiment, the surgical stapler  10  may have a discrete analog switch assembly to actuate the drive source. The switch assembly may be located in any location or on an external surface of the surgical stapler  10 , or be integral with the trigger switch  26 . Alternatively, the drive source  30  may be actuated by a counter clockwise rotation of the protective housing  28  to actuate the drive source. Still further in another embodiment, the drive source  30  may be actuated by the trigger  26  or by simply the lowering an elevation of the lever  24 . 
     Referring now to  FIG. 3 , there is shown an opposite lateral side cross-sectional view of the surgical stapler  10  of  FIG. 2 , having the lever  24  in an elevated position or elevated and away from the handle  14 . The drive shaft  32  of the drive source  30  extends through the lateral side wall of the handle  14  and engages a gear assembly  34 . The gear assembly  34  may have any number of gears to transmit motion from the drive source  30  in protective housing  28  to another member to move a suitable driving member for stapling. The driving member is a gear rack or drive screw or other member to fire the staples in the staple cartridge  21 . Various driving configuration are possible and the present stapler  10  is not limited to any such particular driving arrangement. In this one non-limiting embodiment, the gear assembly  34  has a main gear  36  and two subordinate gears  38 ,  40 . The gear assembly  34  laterally extends into the interior space of the handle  14  as shown. In one embodiment, the gear  36  is a spur gear. In one embodiment, the subordinate gears  38 ,  40  are a pair of pinion gears. In yet another embodiment, instead of a pair of pinion gears  38 ,  40 , the stapler  10  may have one pinion gear. Various gearing configurations are possible and within the scope of the present disclosure. 
     The lever  24  as shown has a first lever side  42  that has a transverse aperture  44  being disposed therethrough. The lever  24  is connected to a member  46  by a link pin  48  through aperture  44  in the lever  24 . The member  46  moves laterally through the endoscopic portion  16 . The member  46  controls the jaws  21 ,  22  shown in  FIG. 1  to open or close and for the surgeon to clamp the jaws of the surgical stapler  10  on or at the desired tissue site. The lever  24  also has an intermediate portion  50 . The intermediate portion  50  has a second aperture  52  being disposed in a bottom side of the lever  24 . The lever  24  is further connected to a second linkage assembly  54  through the second aperture  52  by a second link pin  56 . It should be appreciated that the powered arrangement is not limited to any such device that requires tissue approximation such as a TA surgical stapler such as U.S. Pat. No. 6,817,508 to Racenet, et al. which is herein incorporated by reference in its entirety, and the powered arrangement may encompass other staplers that do not require any such tissue approximation prior to firing. 
     In one embodiment, the second linkage assembly  54  has two discrete links. Each of the links is spaced apart and is connected to one another to form an integral second linkage assembly  54 . The second linkage assembly  54  is for translating a downward force from the lever  24  into an axial lateral force and for moving one or more structures in the handle  14 . The second linkage assembly  54  is further fixedly connected to an interior pin  58  of the handle  14 . The lever  24  still further has an orthogonal notch  60 . The notch  60  is disposed on the lever  24  with the notch being between the transverse aperture  44  and the second aperture  52 . The notch  60  provides clearance and prevents the lever  24  from interfering or otherwise contacting the gear assembly  34  during a firing sequence or otherwise when the drive source  30  is actuated. 
     As shown in the raised position, the free end  62  of the lever  24  rests elevated above the handle  14  as shown. As mentioned, when a stapling site is determined by the operator, the operator will use the jaws  21 ,  22  to compress the tissue at the stapling site to clamp the tissue for a period of time. The surgeon can control the jaws by lowering or closing lever  24  (from the elevated position to a position that rests on the handle  14 ). Upon lowering the lever  24  from the elevated position above the handle  14 , the lever  24  lowers the second linkage assembly  54 . 
     The second linkage assembly  54  forces the lever  24  at the first side  42  to move the member  46 . The member  46  is then manipulated in a lateral axial direction opposite the handle  14 . Thus, member  46  drives the jaws  21 ,  22  at the distal side of the surgical stapler  10  for clamping the selected body tissue between the jaws. In one embodiment, the member  46  may further contact a lead, switch or mechanical member in order to provide an audible or visual alert so as to inform the physician/operator that a preset period of time has elapsed for compression of tissue between the jaws and the firing can begin. Various clamp arrangements are possible and the present arrangement is for illustration purposes as it is envisioned that the clamp may be powered by the drive source  30 , or by a separate drive source. 
     In another embodiment of the surgical stapler  10 , the surgical stapler  10  may be manually actuated for stapling. In the manual embodiment, when the desired stapling is desired, the operator will actuate either a trigger handle (not shown) or in another embodiment will actuate a handle assembly having a linkage. Still in another embodiment, the lever  24  may operate the switch assembly at an end of the lever  24 . The switch assembly  26  may be on any location of the surgical stapler  10  or may be adjacent to the protective housing  28 . 
     The surgical stapler  10  further has a firing member  64 . The firing member  64  is laterally disposed in the handle  14  and can optionally assist with driving an axial drive screw or another driving member to actuate the stapling mechanism in the distal side of the surgical stapler  10 . The firing member  64  may include a single driving member that can control both the clamping and the firing of the surgical stapler  10 . In another embodiment, the firing member  64  can alternatively include separate driving members with one driving member for the firing of the stapler cartridge  21  and another driving member for closing the jaws  21 ,  22 . Various configurations are possible and within the scope of the present disclosure. The firing member  64  is a longitudinal member having a bottom driving surface  65 . However, the longitudinal firing member  64  can be a single component or constructed of other multiple members. The firing member  64  is disposed in a longitudinal manner in the interior of the handle  14  of the surgical stapler  10 . Upon actuation, the motor in the housing  28  spins the main gear  36  that contacts or is connected to the bottom driving surface  65  of the firing member  64 . Gear  36  rotates in a counterclockwise fashion. Thus, in this manner, the drive source  30  will rotate the gear assembly  34  that will move the firing member  64  in an axial direction toward the distal direction of the surgical device  10  and away from the handle  14 . A rotation of the main gear  36  applies a force to the firing member  64  on the bottom driving surface  65  for the purpose of axially moving the firing member in a longitudinal distal manner. This axial movement of the firing member  64  will impart an axial force the corresponding member in the endoscopic portion  16  that will engage the stapling mechanism. 
     A beneficial aspect of the present disclosure is that the drive source  30  will then allow a greater amount of torque to be applied to the driving member  64  relative to a manually actuated apparatus without any motor assembly  30 . A significant aspect of the present disclosure is that the drive source or motor  30  is a low cost device that may be discarded. Given that the drive source  30  may be discarded, the drive source or motor  30  may be connected to an optional analog or digital circuit on a controller to drive the firing member  64  with a predetermined amount of torque so that a considerable amount of power is released from the drive source  30  each instance the firing is desired. Moreover, the surgical stapler  10  provides that the firing member  64  is directly driven by the drive source  30 , or geared by a number of gears for the purpose of actuating the stapling mechanism without undue force or movement applied to the handle  14  or another trigger handle (not shown) of the surgical stapler  10 . This is advantageous since the surgeon can precisely locate the stapler  10  at a site and then fire the stapler  10   
       FIG. 3A  shows an exploded view of a number of components of the surgical stapler  10  of  FIG. 1 . The stapler  10  has a rack  64  that is slidable in the handle portion  14 . The rack  64  interfaces with a clamp tube  102 . On a distal side of the clamp tube  102  is a channel  104 . The channel  104  engages with the clamp tube  102  and a pair of forks  106 ,  108  on a distal side thereof. The stapler  10  also has an upper cover  110  and a lower cover  112 , and an extension tube  114 . The extension tube  114  engages with a collar tube  116 . The stapler  10  also has a rotation knob  118  with a channel portion  120 . The channel portion  120  has a pair of camming surfaces  122  on a distal end. The distal end also has a crimp  124  in a distal side to receive the anvil  22 . 
     In operation, the rack  64  slides and moves the clamp tube  102  distally. The clamp tube  102  is provided to interconnect the handle portion  14  and the extension tube  114 . The channel  104  is slidably mounted for reciprocal longitudinal motion. The extension tube  114  provides support for the surgical stapler  10  and has slots that interface with the collar tube  116 . The surgical stapler  10  also has a support  120  for longitudinal motion and to operate the stapling mechanism as described in  FIG. 2   b . The operation of these components is well known and is disclosed in U.S. Pat. No. 5,318,221 to Green, et al., which is herein incorporated by reference in its entirety. 
     Advantageously, the rack  64  is driven distally to advance the channel  104  in a distal manner. The channel  104  delivers longitudinal motion to a pusher cam bar or an axial drive member as is known in the art for operation of the staple cartridge  21  shown in  FIG. 2   b . It should be appreciated that the components shown in  FIG. 3A  only illustrate one embodiment of the present surgical stapler  10 , and instead of the rack  64 , the surgical stapler  10  may have a drive screw ( FIG. 4 ) for longitudinal motion and in order to actuate the staple cartridge  21 . Referring now to  FIG. 3B , there is shown an exploded view of the anvil  22  and the staple cartridge  132  having an actuation sled  169 . 
     Referring to  FIG. 2   b , the staple cartridge  21  includes an anvil assembly  130  and a cartridge assembly  132  shown in an exploded view for illustration purposes. The anvil assembly  130  includes anvil portion  22  having a plurality of staple deforming concavities (not shown) and a cover plate  136  secured to a top surface of anvil portion  134  to define a cavity (not shown). The cover plate  136  prevents pinching of tissue during clamping and firing of the surgical stapler  10 . The cavity is dimensioned to receive a distal end of an axial drive assembly  138 . 
     The anvil  130  has a longitudinal slot  140  that extends through anvil portion  130  to facilitate passage of retention flange  142  of the axial drive assembly  138  into the anvil slot  140 . A camming surface  144  formed on anvil portion  22  is positioned to engage axial drive assembly  138  to facilitate clamping of tissue. A pair of pivot members  146  formed on anvil portion  130  is positioned within slots  146 ′ formed in carrier  148  to guide the anvil portion  130  between the open and clamped positions. 
     The stapler  10  has a pair of stabilizing members  152  engage a respective shoulder formed on carrier  148  to prevent anvil portion  130  from sliding axially relative to staple cartridge  132  as camming surface of the anvil  130  is deformed. Cartridge assembly  132  includes the carrier  148  which defines an elongated support channel  154 . Elongated support channel  154  is dimensioned and configured to receive the staple cartridge  132  which is shown above the carrier  148  in the exploded view of  FIG. 2   b . Corresponding tabs and slots formed along staple cartridge  132  and elongated support channel  148 ′ function to retain staple cartridge  132  within support channel  154  of carrier  148 . A pair of support struts formed on the staple cartridge  132  are positioned to rest on side walls of carrier  148  to further stabilize staple cartridge  132  within support channel  154 , however other arrangements to support the cartridge  132  on the channel  154  can be used and this arrangement is not limiting. 
     Staple cartridge  132  includes retention slots  156  for receiving a plurality of fasteners  158  and pushers  160 . Longitudinal slots  156  extend through staple cartridge  132  to accommodate upstanding cam wedges  162  of the actuation sled  164 . A central longitudinal slot  166  extends along the length of staple cartridge  132  to facilitate passage of a knife blade (not shown). During operation of surgical stapler  10 , actuation sled  164  is drive distally to translate through longitudinal slot  156  of staple cartridge  132  and to advance cam wedges  162  distally and into sequential contact with pushers  160 , to cause pushers  160  to translate vertically within slots  156  and urge fasteners  158  from slots  156  into the staple deforming cavities of anvil assembly  130  to effect the stapling of tissue. 
     Referring now to  FIG. 4 , there is shown another embodiment of the present disclosure. In this embodiment, the drive source  30  is disposed in an interior space of the handle  14  in a location to balance an overall weight of the surgical stapler  10  for a more ergonomic, comfortable design. The surgical stapler  10 , in this embodiment, has a drive screw  66  as a drive member in contrast to the rack  64  of  FIG. 3A . The drive screw  66  is a threaded rod having a number of helical grooves that are intended to rotate and contact another axial member shown above to actuate the stapling mechanism in the distal location of the surgical stapler  10  once a tissue compression is made by the surgeon. Various configurations are possible, and it should be appreciated that the stapler  10  of the present disclosure is not intended to be limited to any specific stapler mechanism. 
     In one embodiment, the drive source  30  is disposed and lies in a longitudinal plane in the handle  14 . The drive source  30  is disposed substantially parallel to a longitudinal axis of the surgical stapler  10 . This location of the drive source  30  provides for a compact and self powered surgical stapler  10  that may be comfortably balanced and ergonomically grasped by the surgeon. The drive source  30  has the drive shaft  32 . Drive shaft  32  is connected to a first drive gear  68 . The first drive gear  68  has teeth that mesh with, and rotate a number of teeth of a second translating gear  70  as shown. 
     The second translating gear  70  further has a bore or aperture in a center of the second translating gear  70 . The second translating gear  70  further is connected to a collar  72  in a center of the second translating gear. The collar  72  engages the drive screw  66  of the surgical stapler  10 . A clockwise rotation of the second translating gear  70  will also rotate the collar  72  in a similar direction. The collar  72  will then, upon rotation, cooperates and engage with the drive screw  66  to move the drive screw  66  in a distal manner. 
     This rotation of the collar  72  allows the drive screw  66  to rotate and move distally. The drive screw  66  rotates and moves in an axial manner through the bore of the second translating gear  70  and the collar in a direction toward and through the endoscopic portion  16  of the surgical stapler  10 . Upon rotation, the drive screw  66  will traverse laterally by rotation into the endoscopic portion  16  a predetermined amount in a direction away from the handle  14  of the surgical stapler  10  to actuate the stapler mechanism. A significant aspect of this embodiment is that the drive screw  66  has a considerable amount of torque from motor  30  in order to translate the force to the staple mechanism and to form the staples against anvil. 
       FIG. 4A  illustrates another embodiment of the surgical stapler  10 . In this embodiment, the motor  30  is shown unconnected from any power supply for illustration purposes. The motor  30  has a drive shaft  32 . The drive shaft  32  is connected to a first bevel gear  31 . 
     In this embodiment, the motor  30  is disposed at ninety degrees from the drive screw  66 . Upon the actuation of trigger switch  26  ( FIG. 1 ) power will traverse from the battery  29  to the motor  30  ( FIG. 1A ). The energized motor  30  will rotate the motor drive shaft  32  to spin bevel gear  31 . Bevel gear  31  is in contact with second gear  33  that is disposed in concentric fashion with drive screw  66  using member  72  as discussed above. 
     Bevel gear  31  will rotate drive screw  66  to move the drive screw  66  in a longitudinal manner to actuate one or more other components of the surgical stapler  10  such for tissue compression or for stapling. Bevel gear  31  is useful to change a rotation direction of the motor output shaft  32  to move drive screw  66  longitudinally or distally and proximally, and to orient the motor  30  in an advantageous manner relative to the handle  14 . Bevel gear  31  has teeth that can be straight, spiral or hypoid. Although bevel gear  31  is shown as perpendicular to gear  33 , other arrangements are contemplated. Instead, of bevel gear  31  with second gear  33  oriented as shown the surgical stapler  10  may incorporate a hypoid gear which can engage with the axes in different planes. Hypoid gear may further permit different spacing arrangements of the motor  30  relative to the drive screw  66  to further provide for a more compact, balanced and ergonomic stapler design. 
     Referring now to  FIG. 5 , there is shown a cross sectional view of the endoscopic device  16 . Upon actuation, the drive screw  66  rotates a predetermined distance through a central bore  74  in the endoscopic portion  16 . After traversing the predetermined distance, the drive screw  66  will contact a longitudinal firing member  76 . The longitudinal firing member  76  will then contact a complementary structure to fire the staples in the staple cartridge  21  in the distal region of the surgical stapler  10  as is known in the art. In another exemplary embodiment, of the present disclosure, the drive source  30  may be a reversible drive source. Additionally, the staple cartridge  21  may have one row or multiple rows of staples and the surgical stapler  10  may fire with an amount of torque to easily form staples having the desired configuration. 
     In this alternative embodiment, the drive screw  66  may reverse automatically or manually to move proximally at the conclusion of the stapling relative to the endoscopic portion  16 . Upon the drive source  30  actuated by the switch  26  or another manual or automatic actuating device, the drive source rotates the drive shaft  32  in the opposite rotational direction. The drive shaft  32  then rotates the first drive gear  68  in the opposite rotational direction. Thereafter, a number of teeth of the first drive gear  66  rotate the second translating gear  70  in the opposite direction. The second translating gear  70  will then rotate the drive screw  66  in the opposite direction to return the drive screw  68  to an initial position for the next stapling operation. 
     Referring now to  FIG. 6 , there is shown another alternative embodiment of the present disclosure. In this embodiment, the jaws  21 ,  22  are powered by the drive source  30 . The jaws  21 ,  22  may be moved in close alignment with one another to clamp tissue therebetween and be powered by motor or drive source  30 . The surgical stapler  10  has a drive source  30  that has a drive gear  74  being connected to the output drive shaft (not shown) of the motor  30  or drive source. The drive gear  74  is directly connected to the drive source  30 , however alternatively may be connected to the drive source  30  by another gear or by another linkage depending on the space constraints of the handle  14 . The surgical stapler  10  further has a second translation gear  76 . The second translation gear  76  also is connected through the drive screw  66  that drives the drive screw  66  to fire the staple cartridge  21  as discussed previously. 
     In this embodiment, the lever  24  is connected to the linkage assembly  54  at the intermediate portion  50  of the lever  24 . The lever  24  when lowered from the elevated position, imparts a downward force on the linkage assembly  54 . Thereafter, the linkage assembly  54  fixed at one end by the interior pin  58  rotates about the interior pin and moves the lever  24  in an axial manner. This moves and advances a linkage (not shown) for clamping the tissue. Still further, the member or another component may actuate a timer (not shown) or display to alert the physician/operator to activate the trigger and to initiate the drive source  30 . In still another embodiment of the present disclosure, the clamping may be mechanically connected or linked to the drive source  30  to provide for a powered compression of tissue. In still another embodiment, the clamping can be performed simultaneously with the firing of the trigger handle  26 , and may be powered by the drive source  30  as opposed to independently of firing. 
     Once the actuation of the drive source  30  occurs, the drive source will turn the drive gear  74 . The drive gear  74  will then directly rotate the second translation gear  76  and the drive screw  66  disposed directly through the bore of the second translation gear. Again, the drive screw  66  will then impart the required axial force to discharge the staples from the staple cartridge  21  in the distal location of the surgical stapler  10 . As mentioned, once the drive screw  66  travels a predetermined distance, the drive screw  66  will actuate the corresponding stapler mechanism to fire the staples in the staple cartridge  21 . 
     Although shown as an endoscopic surgical stapler, the present drive system may be used with any surgical stapling device known in the art, such as endoscopic surgical stapling devices, a multi-fire GIA surgical stapler, a TA surgical stapling device, and/or any other surgical stapler device known in the art. The present instrument may also be used with a single drive surgical stapler that drives both the clamping device of the jaws  21 ,  22  and the stapling device. 
     It should be understood that the foregoing description is only illustrative of the present disclosure. Various alternatives and modifications can be devised by those skilled in the art without departing from the disclosure. Accordingly, the present disclosure is intended to embrace all such alternatives, modifications and variances. The embodiments described with reference to the attached drawing figures are presented only to demonstrate certain examples of the disclosure. Other elements, steps, methods and techniques that are insubstantially different from those described above and/or in the appended claims are also intended to be within the scope of the disclosure.