Surgical stapling instrument

A surgical stapling instrument includes first and second body members pivotally and detachably connected to each other, each having an elongated jaw to grip tissue therebetween to be stapled together. The instrument further includes a toggle joint pivotally connected on one of said body members and adapted to engage the other body member to lock the body members together. Various latching mechanisms are provided to releasably latch the proximal ends of the body members together prior to locking the jaws about the tissue to be stapled.

BACKGROUND OF THE INVENTION 
This invention relates to surgical instruments and more particularly to a 
surgical instrument for applying spaced rows of staples to internal 
organs. Instruments of this type include a pair of elongated jaw members, 
one of which carries a staple cartridge with rows of staples and the other 
of which carries an anvil. A pusher bar and knife assembly is moved along 
the jaws to eject the staples by a camming action acting on the staple 
pushers associated with the individual staples to close the staples 
against the anvil through the tissue gripped between the jaws. The knife 
cuts the tissue along a line between the staple rows. One instrument of 
this type is disclosed, for example, in U.S. Pat. No. 3,079,606. 
Forces needed to clamp or compress the tissue between the jaws in 
instruments such as these must be overcome when locking the jaws together. 
It also is desirable in certain instances to be able to latch releasably 
the proximal ends of the body members carrying the jaws before clamping 
the tissue between the jaws. 
SUMMARY OF THE INVENTION 
It is an object of the present invention to provide a surgical stapling 
instrument of the type described above in which the action of locking the 
instrument to overcome tissue clamping forces is accomplished with greater 
ease. 
It is a further object of the present invention to provide a surgical 
stapling instrument which can be releasably latched together prior to 
locking the instrument when clamping the tissue between the jaws. 
A surgical stapling instrument capable of internal stapling procedures is 
provided having first and second body members which are pivotally and 
detachably connected to each other, each body having an elongated jaw. One 
of the jaws is adapted to receive longitudinal rows of staples. An 
elongated bar is provided which is slidable longitudinally along said jaws 
to eject staples from one jaw and shape the staples against anvil means 
provided on the other jaw to form rows of staples in tissue gripped 
between the jaws. Locking means are provided for releasably locking said 
jaws in a tissue gripping staple inserting position which means include a 
toggle joint with a first end pivotally mounted to one of said body 
members, a second end adapted to engage the same body member distally of 
the first end of the toggle joint. The toggle joint also includes a knee 
disposed between the first and second ends of the toggle joint. The second 
end of the toggle joint is also adapted to engage a portion of the other 
body member to lock the jaws in tissue gripping position when the knee is 
straightened. 
More particularly the toggle joint includes a lever bar which engages the 
one body member at one end and a linking bar pivotally mounted to the one 
body member. The linking bar at its other end is pivotally connected to 
the lever bar intermediate its ends. In one embodiment, a freely rotatable 
roller is mounted to the lever bar at the end which distally engages the 
one body member. The roller provides a low friction engagement. 
The other body member includes a frame having spaced apart sides which 
extend away from the other body member and are adapted to receive the one 
body member therebetween. The spaced apart sides each have a slot aligned 
with one another and these slots receive a pin mounted in the end of the 
lever bar which engages the one body as the knee of the toggle joint is 
straightened. 
The frame of the instrument includes a first handle portion while a second 
handle portion is attached to the lever bar, the handle portions 
facilitating gripping of the instrument by the user. 
A surgical stapling instrument is provided with latching means for 
releasably latching the proximal ends of the first and second body 
members. In one embodiment a key hole slot is provided in one body member 
and a pin movable between first and second positions is coupled to the 
other body member. The pin is biased in the first position. When the pin 
is moved to the second position a narrowed portion of the pin will enter 
the key hole slot. When the pin returns to the second position, the pin is 
locked in the slot. A camming surface on the proximal end of the one body 
engages a bevel surface on the pin to move the pin to the second position 
when the body members are brought together. 
Alternatively the latching means comprises a slot in the proximal end of 
one body member and a pin coupled to the other body member. A latch member 
is pivotally coupled to the one body member spaced apart from the slot and 
rotatable between a latching position and a second position. A cam surface 
on the latch member moves the latch member to the second position when the 
pin enters the slot. The latch member is biased to return to the latching 
position about the pin as the pin moves farther into the slot.

DETAILED DESCRIPTION OF THE DRAWINGS 
Referring to the drawings, a surgical instrument for internal stapling of 
gastric and intestinal walls with spaced parallel rows of metallic staples 
is shown designated generally 100. The instrument 100 includes first and 
second body members 102 and 104 having a elongated staple inserting jaw 
106 and a staple clinching jaw 108, respectively. The second body member 
104 is detachably and pivotally connected to the first body member 102 
adjacent their proximal ends by means of a pivot pin 110 on the body 
member 102 received in a slot 112 on the body member 104. Means designated 
generally 114 to be described in more detail hereinafter are provided to 
releasably lock the body members 102 and 104 together with the jaws 106 
and 108 carried thereby in operational position. 
Referring to FIG. 3, a longitudinal groove 120 is provided in an inner 
surface 121 of the staple inserting jaw 106 which groove opens towards the 
staple clinching jaw 108. The staple clinching jaw 108 also has a 
longitudinal slot 122 in its inner surface 123 and in alignment with the 
groove 120. The staple inserting jaw 106 includes a plurality of 
longitudinally spaced staple receiving recesses 224 and 226 in the 
sidewall 228 and 230, respectively, of the groove 120 and slidably 
disposed in the recesses 224 and 226 are staple driving members 224' and 
226'. The staple driving members 224' and 226' are provided with lugs 232 
and 234, respectively, projecting into the groove 120. A staple cartridge 
removable from the jaw 106 and including the longitudinal groove, staple 
recesses, staples, staple driving members, etc. could be provided. The 
cartridge would be loadable into an appropriate recess in the staple 
inserting jaw 106. Many examples of such cartridges are provided in the 
prior art, e.g. see U.S. Pat. No. 3,490,675. 
Referring now to FIGS. 1 and 6, an elongated pusher bar 140 is shown which 
acts as a staple driver actuating means. The pusher bar 140 includes a 
laterally projecting pin 142 slidably received in a slot or groove 144 in 
the body member 102. The bar 140 is also slidably received in the groove 
120 of the staple inserting jaw 106. The pusher bar 140 includes at its 
distal end a wedge 146 and, proximally thereof, a downwardly projecting 
knife blade 148. The bar 140 is provided adjacent the proximal ends 
thereof with a finger or thumb engaging tab 150 to be used to operate bar 
140. In order to prevent inadvertent operation of the bar 140 a spring 152 
is provided attached to the body member 102 at 154 and with a pin 156 
projecting into a notch 158 on the bar 140. 
Referring to FIG. 4, the staple clinching jaw 108 is provided with staple 
clinching anvil portion 160 disposed opposite the staple receiving 
recesses 224 and 226 in the staple inserting jaw. 
The general construction and operation of the illustrated instrument is 
similar to many of the instruments described in several patents, most 
notably U.S. Pat. No. 3,079,606. Accordingly, the following description 
will only deal in detail with modified features of the instrument and for 
a fuller understanding of the principles and operation of the instrument, 
reference may be made to the above patent the disclosure of which is 
incorporated herein by reference. 
Referring now to FIG. 1 and FIGS. 5-7, the improved locking means 114 
comprises a toggle joint having one end 162 pivotally attached to the 
second body member 104 at 164 and a second end 166 adapted to engage the 
outer surface 168 of the second body member on the second body member's 
opposite side from the inner surface 123. The toggle joint further 
comprises a knee portion 170 intermediate the ends 162 and 166. 
The toggle joint includes a lever bar 174 with one end forming the end 166 
of the toggle joint and with an opposite free end 176, and a linking bar 
178 with one end forming the end 162 of the toggle joint and the opposite 
end 180 pivotally connected to the lever bar 174 intermediate its ends 166 
and 176. 
End 166 of toggle joint 114 includes a roller 182 adapted to engage and 
roll along outer surface 168 when the knee 170 of the joint is 
straightened by pushing it toward the second body member 104. End 166 also 
includes a pin 184 coupled to spaced apart ear portions 186 at end 166 of 
lever bar 174. The ear portions extend laterally away from the lever bar 
174 at end 166. The toggle joint 114 further includes a handle portion 169 
connected in any suitable manner to the lever bar 174. 
The first body member includes a frame 188 having a handle portion 190 and 
spaced apart sides 192 which extend away from the first body member 102 on 
opposite sides of the proximal portion of the jaw 106. The sides 192 are 
adapted to receive the second body member 104 therebetween. This helps to 
insure that the jaws 106 and 108 are in proper lateral alignment during 
operation of the instrument. A further aligning and locating means is 
provided in the form of a pointed pin 193 secured to the staple clinching 
jaw 108 adjacent the outer end thereof and the pointed end of the pin is 
received in the groove 120 in the staple inserting jaw 106 when the parts 
are in the operative position. 
The spaced apart sides 192 each have a slot 196 aligned with on another for 
receiving the pin 184 on the end 166 of lever bar 174. The slot has a wide 
open mouth 197 which narrows at its distal end as it extends generally 
longitudinally from the proximal end of the instrument to the distal end. 
The slots are located in a portion of the spaced apart sides 192 which 
extend beyond the second body member 104 when the body members are in the 
tissue gripping position. 
With the tissue to be sutured placed between the jaws and with the first 
and second body members coupled together by placing the pin 110 in groove 
112, the instrument is locked together as follows: the knee 170 of the 
toggle joint 114 is moved toward the second body member 104 by squeezing 
the handle portions 169 and 190 together. As the end 166 rolls along 
surface 168 the pin 184 will engage the mouth 197 of the slots 196. As the 
knee is straightened further the longitudinal action of the end 166 along 
the surface 168 is translated into a clamping force by pin 184 on slot 
surface 198 pulling the jaws 100 and 108 together about the tissue. 
Referring now to FIGS. 8 and 9 a means for quick latching of the proximal 
ends of the body members 102' and 104' is provided FIG. 8 shows a 
modification 112' to the slot 112. Slot 112' is shaped like a key hole 
with the narrow part of the slot 112' extending to the side edge of 
enlarged proximal end of body member 104'. The narrow part of the slot is 
in communication with an interior circular hole portion 300. The side edge 
of the enlarged proximal end containing the slot has a cam surface 301. 
In FIG. 9, a modified pin 110' is coupled to the parallel and spaced apart 
walls of the proximal end of the first body member by a rivet or fastener 
308. A spring 307 attached to the body member 104 at 308 holds the pin 
110' in place and biases it to a first position. A portion of the pin 110' 
protrudes through a hole in the wall of body member 104' opposite the 
fastener 308. 
In general, the diameter of the pin 110' is larger than the narrow part of 
slot 112' but the pin 110' has a narrow central portion 302 with an 
adjacent bevel surface 305 which transitions between the central narrow 
portion and the remainder of the pin. When the cam surface 301 of body 
member 104' engages the bevelled surface 305, the pin 110' moves against 
the spring 307 aligning the narrow portion 302 of the pin 110' with the 
narrow part of the key hole slot 112'. As the pin moves, into the circular 
portion 300 of the slot 112', the spring 307 moves the pin into its biased 
first position with the larger diameter of the pin within the hole 300 and 
aligned with the narrow part of the slot. This captures the pin 110' 
within the slot 112' since the larger diameter of the pin is larger than 
the narrow part of the slot. The body members are thereby latched 
together. By latching, it is meant that the parts are fastened together. 
The latch is easily released by simply pushing pin 110' axially against 
the spring 307 in the direction of arrow 309 until slot 112' can slip over 
the narrow portion 302 of the pin 110'. 
An alternate latch mechanism for operating with the structure of FIG. 8 is 
shown in FIG. 10. A latch member 400 is attached by pin 164" to the body 
member 104" spaced apart from slot 112". Latch member 400 is free to 
rotate about pin 164 from the latch position shown in FIG. 10 to a second 
position The latch member is biased in the latch position by spring 402 
which is mounted to body member 104" and engages a handle portion 405 
which extends away from the proximal position of the instrument. 
As the pin 110" is inserted into the slot 112", the cam surface 401 engages 
the pin rotating the latch member 400 in the direction of arrow 404. As 
the body member 104" is pushed farther in the direction of body member 
102", the latch member 400 rotates farther until the latch member slips by 
pin 110" and the interior flat surface 403 on the hook portion 406 engages 
the pin 110" to latch the body members together. To detach the body 
members, the member 405 is pushed in the direction 404 releasing pin 110" 
from slot 112". 
It will be obvious to those skilled in the art that various changes may be 
made in the invention without departing from the spirit and scope thereof 
and therefore the invention is not limited by that which is shown in the 
drawings and described in the specification, but only as indicated in the 
appended claims.