Robotic loader for surgical stapling cartridge

A means and method for inserting drivers into a surgical stapling cartridge, including a pallet that holds the cartridge firmly. The pallet has a central slot and laterally positioned lip members that are biased toward the slot. The cartridge is positioned in the slot and the lip members are released to extend their lips over the lateral flanges on the cartridge, thereby holding the cartridge in position. A finger extends into a recess formed at one end of the cartridge, thereby positively positioning the cartridge in the slot. The cartridge is released for removal by a tongue inserted between the lip members, thereby separating them by displacement.

(e) BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates generally to a means and a method for loading a surgical stapling cartridge.

2. Description of the Related Art

It is known in the prior art mechanically to insert drivers into surgical stapling cartridges, as shown in U.S. Pat. No. 5,836,147 to Schnipke, U.S. Pat. No. 5,635,928 to Schnipke, and U.S. Pat. No. 6,158,205 to Schnipke et al., all of which are incorporated herein by reference. However, the mechanisms for this insertion require dexterity by trained people who are able to position the frames that contain the drivers and the cartridges, and actuate the machines to insert the tiny drivers into the precisely formed holes in the cartridges. After a fraction of the drivers are inserted by one machine, the cartridge is then manually transported to the next machine, which inserts another fraction of the drivers.

If any drivers are improperly inserted into a cartridge, or are not inserted, the cartridge is either discarded or repaired, which means that errors in insertion of the tiny parts can result in time and/or product lost. Such problems in manufacturing occur due to human error, and therefore it is desirable to mechanize the process to reduce the number of opportunities for error.

(f) BRIEF SUMMARY OF THE INVENTION

The invention is a moveable pallet used in a system in which robotic arms load cartridges. The pallet firmly holds a surgical stapling cartridge as drivers are inserted therein. The pallet comprises a base having a lower surface for seating on a conveyor. An elongated slot is formed in an upper surface of the base for holding the cartridge. A first cartridge-retaining lip member is movably mounted to the base on a first side of the slot, said first lip member being biased toward the slot. The lip member has a lip extending into the slot. A second cartridge-retaining lip member is mounted to the base on a second side of the slot. The second lip member is preferably moveable and biased toward the slot, and it has a lip extending into the slot.

A gap is formed between the first and second lip members to receive a tongue that is inserted upwardly through an aperture in the base. The tongue seats against opposing surfaces of the lip members and displaces the lip members away from the slot to release the cartridge. A finger is mounted to the base near a first longitudinal end of the slot, and extends into the slot for seating within a recess of the cartridge.

A preferred pallet has at least one tapered cavity formed in the lower surface of the base for receiving a foot for positively positioning the pallet horizontally. The preferred pallet also has at least one vertical registration surface that seats against at least two vertical registration arms for positively positioning the pallet vertically.

A tool is used for picking up a frame to which a plurality of drivers for the surgical stapling cartridge is mounted. The tool comprises a prime mover and a first finger drivingly linked to the prime mover. The first finger has a first pair of transverse planar panels formed in an inwardly facing surface of the first finger. The first pair of transverse planar panels is adapted to seat against corresponding surfaces on the driver frame. A second finger is connected to the prime mover, and has a second pair of transverse planar panels formed in an inwardly facing surface of the second finger that is substantially opposed to the inwardly facing surface of the first finger. The second pair of transverse planar panels is adapted to seat against corresponding surfaces of the driver frame.

A method of filling a surgical stapling cartridge is also contemplated. The method comprises holding firmly a cartridge in the above-described pallet, conveying the pallet to a first station, raising the pallet above the conveyor and inserting a plurality of drivers into the cartridge when the pallet is in a raised position. The pallet is next lowered back onto the conveyor and conveyed to a second station.

(g) BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1is a view in perspective illustrating the preferred pallet with a cartridge in an operable position.

FIG. 2is a view in perspective illustrating the cartridge holder, which is a component of the pallet.

FIG. 3is a view in perspective illustrating the plate, which is a component of the pallet.

FIG. 4is a view in perspective illustrating the ring, which is a component of the pallet.

FIG. 5is a view in perspective illustrating a lip member.

FIG. 6is a side view in section through the line6—6ofFIG. 1.

FIG. 7is a side view in section through the line7—7ofFIG. 1.

FIG. 8is a view in perspective illustrating a preferred structure for displacing the lip members apart.

FIG. 9is a view in perspective illustrating the T-shaped finger that extends into a recess near one end of the cartridge to positively position the cartridge in the pallet.

FIG. 10is a view in perspective illustrating the preferred structure for lifting the pallet and horizontally aligning it relative to a machine.

FIG. 11is a view in perspective illustrating a preferred machine for inserting drivers into a cartridge, and a pair of cantilevered arms that define the upper limit of the pallet travel above the conveyor.

FIG. 12is a view in perspective illustrating a preferred socket.

FIG. 13is a view in perspective illustrating a preferred socket.

FIG. 14is a view in perspective illustrating the preferred end of arm tooling for gripping the frame to which drivers are mounted.

FIG. 15is a view in perspective illustrating a preferred pallet for holding supplies, such as drivers.

FIG. 16is a view in perspective illustrating one finger of the special end of arm tooling.

FIG. 17is a view in perspective illustrating a second finger of the special end of arm tooling.

FIG. 18is a view in perspective illustrating special end of arm tooling for gripping swing tab frames, and shows a swing tab frame in an operable position.

FIG. 19is a view in perspective illustrating special end of arm tooling for gripping swing tab frames.

FIG. 20is a view in perspective illustrating a preferred pallet for holding supplies, such as swing tabs.

(h) DETAILED DESCRIPTION OF THE INVENTION

The preferred pallet10is shown inFIG. 1with a surgical stapling cartridge12mounted therein in an operable position. The pallet10is essentially made up of two components: the cartridge holder20shown inFIG. 2, and the base14shown inFIGS. 3 and 4. The base14is made of two subcomponents: the plate16and the ring18. The plate16and the components of the cartridge holder20are preferably made of steel. The plate16forms a rigid frame to which the other components of the pallet10attach. The ring18is preferably made of a low friction polymer, such as is sold in association with the trademark DELRIN. The ring18, plate16and the cartridge holding apparatus20are securely fixed together, such as by screws.

The lip members22and24, both essentially identical to the lip member22shown inFIG. 5, are mounted in the chambers32and34, respectively, formed in the cartridge holder20. The lip members22and24have lips26and28, respectively, both essentially identical to the lip26shown inFIG. 5. Each of the lip members is housed in its respective chamber with the lip member seating against the surfaces that define the chamber, but with the ability of the lip members to be displaced laterally toward and away from the slot40. Each lip member is biased toward the slot40, such as by coil springs. The cover panels42and44keep the lip members from coming out of the chambers, but permit the lip members to slide within the chamber.

In their operable position show inFIG. 1, the lips26and28extend from the chambers32and34into the slot40, which is the region of the pallet10in which the cartridge12is held when it is mounted in the pallet10(seeFIG. 2). The cartridge12is restrained in the slot40by the lips26and28extending over the lateral flanges on the cartridge12, which lateral flanges are conventional for surgical stapling cartridges of the type shown. Thus, the cartridge is held firmly and rigidly to the pallet10, and cannot be removed without either breaking the flanges or retracting the lips26and28away from the flanges.

Before the pallet10is first loaded with a cartridge, the lips26and28are retracted by the structure shown inFIG. 8. The pallet10is lifted off of a conveyor on which it rests (not viable) by a prime mover, such as the pneumatic ram59, which displaces the plate61upwardly. The plate61has rigidly mounted feet71,73,75(and another foot that is not visible inFIG. 8) that cooperate to align and lift the pallet10as described below. After the pallet10is lifted a predetermined distance, its upper surface seats against the undersides of the rigid flanges63and65, which prevent any upward movement beyond the flanges.

Also rigidly mounted to the plate61is a tongue that is aligned with an aperture50, shown inFIG. 3, formed through the plate16. As the plate61is displaced upwardly before the feet contact the pallet, the tongue60extends through the ring18, through the aperture50and through the aperture52of the cartridge holder20shown inFIG. 2. The edges of the tongue60seat against the opposed, tapered surfaces (surface27on lip member22and an essentially identical surface on lip member24) of the lip members22and24. This seating begins to displace the lip members outwardly away from the slot40, and as the tongue is extended further into the aperture52and the feet contact the pallet10, the tongue60further displaces the lip members22and24outwardly, thereby retracting the lips26and28from the slot40. Once the lips26and28are no longer in the slot40, the cartridge12can be inserted in the slot40, and the tongue can be withdrawn, thereby permitting the biased lip members to be displaced inwardly to hold the cartridge12.

The cartridge12is thus held in the pallet10by the slot and the cartridge holding apparatus. However, the cartridge12must also be precisely positioned in the slot so that the apertures in the cartridge12are correctly positioned relative to the machines, described below, that insert drivers into the cartridge. The T-shaped finger54is mounted in the T-shaped opening62in the cartridge holder20. The finger54extends upwardly into the slot, and when the cartridge is placed in the slot40, the finger54extends into a recess formed in one end on the underside of the cartridge12as shown inFIG. 6. The finger54thus precisely positions the cartridge12in the slot40by restricting the cartridge's movement in the plane of the pallet10. The lips26and28restrict movement of the cartridge12outside of the plane of the pallet10.

Once the cartridge12is precisely positioned in the pallet10, the pallet must be precisely positioned relative to each machine that operates on the cartridge12. The pallet is preferably conveyed along by a conveyor system, such as a conventional conveyor sold by Flexlink AB. This conveyor transports pallets with cartridges between several stations, each station having a machine that inserts drivers or a swing tab into a cartridge. The machines are essentially conventional, as described herein and in the patents incorporated by reference. However, the cooperation of the pallets with the machines is not conventional, as described below.

At each station, the pallet10is halted by a retractable pin that extends into the path of the pallet10on the conveyor, thus preventing the passage of the pallet. The pin preferably extends upwardly and the pallet is stopped when the pallet's leading edge strikes the pin. The pin is positioned to stop the pallet when the pallet is positioned directly over the apparatus shown inFIG. 10, and directly below the apparatus shown inFIG. 11.

The apparatus shown inFIG. 10includes a prime mover, which is preferably the pneumatic ram64, that is drivingly linked to the plate66. The plate66has four tapered feet67,68,69, and70. Corresponding to the feet67–70are the sockets77,78,79and80, one of which is shown inFIGS. 12 and 13and which is representative of all of the sockets77–80. The sockets77–80are mounted to the pallet10by screws (not shown) extending through openings77′,78′,79′ and80′, respectively, shown inFIG. 2. The sockets77–80seat against the underside of the cartridge holding apparatus20, and are contained within apertures82,83,84and85, respectively, formed in the base16, and apertures86,87,88and89, respectively, formed in the ring18.

The tapered cavities of the sockets77–80receive the tapered feet67–70, respectively. Because the cavities and feet are tapered, a degree of initial misalignment does not cause the pallet to stay misaligned relative to the machine that will operate on the cartridge. The tapered structures permit the misalignment to be corrected as the plate66raises the pallet10off of the conveyor upwardly toward the machine100shown inFIG. 11. Any misalignment of the pallet10relative to the plate66disappears as the tapered surfaces of the feet and cavities slide relative to one another during lifting. Thus, once the feet67–70seat in the sockets77–80, there is extremely precise alignment of the pallet10with the plate66, thus precisely positioning the pallet10horizontally relative to the machine.

As the pallet10is raised up to the machine100, the upper surface of the pallet10, and preferably the tops of the cover panels42and44, seat against the undersides of the cantilevered arms102and104. The position of the pallet10when the top surfaces of the cover panels42and44seat against the arms102and104is precisely predetermined, so that when this seating occurs, the pallet10, and the attached cartridge12, are positioned for insertion of the drivers into the cartridge. Thus, the cooperation between the tapered feet and the tapered cavities registers the horizontal position of the pallet10relative to the machine100as described above, and the cooperation between the upper surfaces of the cover panels42and44and the cantilevered arms102and104registers the vertical position of the pallet10relative to the machine100.

Once the pallet10is in the aligned position, the machine100functions in an essentially conventional manner to insert the drivers into the cartridge12. As is known in the industry, such insertion ordinarily takes place in several stations, each of which inserts a fraction of the total number of drivers. Thus, once the first fraction of drivers is inserted, the ram64lowers the pallet10back onto the conveyor, the retractable pin retracts and the conveyor conveys the pallet10to the next station at which the process of lifting and inserting drivers is repeated, except that the next set of drivers is inserted.

The pallet10has a slot19in one side of the ring18. The slot has a width and a depth that permits the pin that stops the pallet10to pass therethrough. This accommodates the action of the retractable pin, which is to retract momentarily when the pallet is supposed to be driven past the pin, and then protrude upwardly to its pallet stopping position even while the just-released pallet is still directly over the pin. The slot19passes directly over the pin, and therefore the pin has no effect on the pallet that was just released to be conveyed downstream. However, the pin does seat against and stop the leading edge of the next upstream pallet.

At some time drivers must be positioned in the machine100in order to be inserted by the machine into a cartridge. A plurality of drivers is commonly molded to a frame108during manufacture. The frame108is a convenient structure used to grasp the plurality of drivers, which are otherwise too small to conveniently grasp and manipulate individually by hand. Thus, the plurality of drivers attached to the frame108can be positioned by hand in the region106of the machine100. Alternatively, the drivers can be positioned in the region106by a mechanism, such as a conventional robotic arm using a unique gripping tool.

In the preferred embodiment, many frames, such as the frame108, are stacked on the rods112of the driver pallet110, shown inFIG. 15. The frames are aligned by hand or by another robotic arm, so that a robotic arm can pick them individually off of the pallet110and place them in the region106. A somewhat similar pallet220(FIG. 20) holds other supplies, such as swing tabs, which are installed in cartridges at another station. The tooling necessary to grasp the frames of the drivers and the swing tabs is especially designed to work with the frames, and is described next.

The end of arm tooling for the robotic arm is shown inFIG. 14grasping the frame108between the tips of two fingers114and116. The first finger114and the second finger116are drivingly linked to a prime mover, such as the servomotor of the robotic arm, which displaces the fingers114and116relative to one another. Of course, only one finger need be driven by the servomotor and the other could be merely connected to the robotic arm. The first finger114has an inwardly facing surface124, and the second finger has an inwardly facing surface126, which are preferably in close proximity to one another once the fingers grasp the frame108and the arm moves the frame108to the region106.

The first finger114has a pair of transverse planar panels130and131formed in the inwardly facing surface124near the tip of the finger114. The planar panels130and131are adapted to seat against the corresponding surfaces130′ and131′ on the driver frame as shown inFIG. 14.

The second finger has a pair of transverse planar panels134and135formed in the inwardly facing surface126near the tip of the finger116. The planar panels134and135are adapted to seat against the corresponding surfaces134′ and135′ on the driver frame as shown inFIG. 14. By clamping the frame108between the fingers114and116, the robotic arm can lift the frame108off of the pallet110and then move it over to the region106with precision. The precision arises from the exact registration of the transverse panels130and131seating against the corresponding surfaces130′ and131′. Because the transverse panels130and131form a V-shaped structure, that structure seats precisely in the V-shaped intersection of the corresponding surfaces130′ and131′. A similar result arises because of the planar panels134and135seating against the corresponding surfaces134′ and135′ of the frame108.

There are also substantially parallel planar panels132and133that intersect the transverse planar panels130and131, respectively, at the ends of the transverse planar panels130and131closest to the tip of the finger114. These parallel panels132and133seat against the underside of the frame108to positively position it along the length of the finger114. The substantially parallel panels136and137intersect the transverse planar panels134and135, respectively, at the ends of the transverse planar panels134and135closest to the tip of the finger116. This arrangement of planar panels provides precision in the position of the frame108.

The station in which swing tabs are inserted in the cartridges has an additional robotic arm that uses a special tool201to grip the swing tab frame200, shown inFIGS. 18 and 19, and remove it from the pallet220shown inFIG. 20. The tool201has fingers202and204, which are forked to form legs206,207,208and209. The legs206–209have transverse planar panels formed in the fingers near the tips in which the angled ends of the swing tab frame200are inserted to grip the frame200as shown inFIG. 18. These transverse planar panels are substantially equivalent in function to the planar panels described above in association withFIGS. 14,16and17. Thus, the angled ends of the swing tab frame200extend into the cavities formed by the transverse planar panels, and the fingers grip the frame200therebetween under the force of a prime mover, such as a servomotor on the robotic arm.

The entire process of putting cartridges in pallets, inserting drivers and swing tabs, and conveying the pallets is computer controlled, inasmuch as each pallet is conveyed by the conveyor, which is started and stopped (if necessary) by a central computer. Additionally, sensors at each station detect whether a pallet is present at each station by detecting a device mounted in the side of each pallet, such as the screw150in the pallet10(FIG. 1). When a pallet is detected, the computer actuates the pneumatic ram apparatus to raise the pallet to the position in which it can be operated on by the machine at that station. Once the machine is finished with its task, the computer actuates the ram to lower the pallet and the retractable pin is activated by the computer to be retracted to permit the pallet to be conveyed further by the conveyor. Essentially all functions are either controlled or monitored by the central computer. The only human monitoring, other than viewing the apparatus for malfunctions, is the placing of cartridges in the pallet initially, removing the finished cartridges from the pallets and placing supplies, such as driver frames and swing tab frames on the pallets that supply the robotic arms. However, it is contemplated that all of these functions could be mechanized.

While certain preferred embodiments of the present invention have been disclosed in detail, it is to be understood that various modifications may be adopted without departing from the spirit of the invention or scope of the following claims.