Flexible forceps

Abstract

Flexible forceps including a flexible sheath having a flexible element extending therethrough, a handle on one end for moving said flexible element axially and a pair of jaws on the other end pivoted to a sleeve joined to the sheath and to a trocar assembly connected to the flexible element and slidably disposed in said sleeve.

Description

This invention relates to forceps and more specifically to novel and improved flexible forceps which afford more reliable and dependable operation.

Flexible forceps utilizing an elongated flexible tubular sheath with a flexible member extending therethrough have a pair of jaws on the distal end and an operating handle on the proximal end. Since the jaws may be of the order of 0.050 inch to 0.100 inch in diameter, known structures have required tedious and timeconsuming operations in the manufacture thereof in an effort to attain a reasonable degree of dependability and reliability with the result that manufacturing costs have been relatively high.

This invention overcomes the difficulties heretofore encountered in the manufacture of flexible forceps and provides a novel and improved flexible forcep structure that provides an arrangement and organization of elements which greatly simplifies manufacture and therefore materially reduces the cost of production.

Another object of the invention resides in the provision of a novel and improved jaw assembly at the distal end of the flexible member which simplifies the coupling of the jaws with the axially movable element within the flexible member. The improved structure also produces precise movement of the jaws toward and away from one another and when moved to the closed position will produce a positive cutting action. Since the jaws are essentially hemispherical, sample tissue severed by the jaws will be completely severed and retained by the jaws as long as they are held in the closed position.

Still another object of the invention resides in the provision of a novel and improved jaw construction for flexible forceps embodying replacable inserts having cutting edges therein and therefore avoid the need for frequent replacement of the jaws.

A still further object of the invention resides in the provision of a novel and improved operating handle which enables more effective control and operation of the forceps.

The above and other objects and advantages of the invention will become more apparent from the following description and accompanying drawings forming part of this application.

In the drawings:

FIG. 1 is a side elevational view of flexible forceps in accordance with the invention and with the jaws in the closed position;

FIG. 2 is a side elevational view similar to FIG. 1 with the jaws in the open position;

FIG. 3 is an enlarged perspective view of the forcep handle with the flexible shaft broken away to show the construction thereof;

FIG. 4 is a longitudinal cross sectional view of the handle shown in FIG. 3;

FIG. 5 is an exploded perspective view of the jaw assembly on the distal end of the tubular operating shaft and the actuating rod which forms part of the handle structure;

FIG. 6 is a longitudinal cross sectional view of the distal end of the flexible shaft including the jaw assembly in the closed position;

FIG. 7 is a longitudinal cross sectional view of FIG. 6 taken along the line 7--7 thereof;

FIGS. 8, and 9 are cross sectional views of FIG. 6 taken along the lines 8--8, and 9--9 thereof respectively;

FIG. 10 is a longitudinal cross sectional view similar to FIG. 6 but with jaws in the open position; FIG. 11 is a fragmentary longitudinal cross sectional view of a modified jaw construction;

FIG. 12 is a cross sectional view of FIG. 11 taken along the line 12--12 thereof;

FIGS. 13 and 14 are perspective views of jaw inserts for the form of the invention shown in FIGS. 11 and 12;

FIG. 15 is a further modification of the jaw construction wherein the insert includes a helical cutting edge;

FIG. 16 is a cross sectional view of FIG. 15 taken along the line 16--16 thereof.

FIG. 17 is a perspective view of the jaw insert of FIGS. 15 and 16;

FIG. 18 is a longitudinal cross sectional view of a modified embodiment of the invention with the jaws in the closed position; and

FIG. 19 is a view similar to FIG. 18 with the jaws in the open position;

Referring now to the drawings and more specifically to FIGS. 1 and 2, the flexible forceps in accordance with the invention comprises an elongated flexible shaft of tubular construction generally denoted by the numeral 10, a handle assembly 11 on the proximal end and a jaw assembly 12 on the distal end. The flexible shaft is generally formed of an outer sheath 13 of spring-type wire wound in the form of a tight helix and having an elongated flexible element 14 extending therethrough and slidably movable relative thereto. The flexible element 14 may be in the form of a thin solid rod or wire of metal, plastic, or other suitable material and the sheath 13 may take any suitable form and be made of any suitable material provided that it has adequate strength and flexibility.

The handle 11 includes a fitting 15 having a narrow shank portion 16 and a flared portion 17. The fitting 15 has a central opening 18 extending therethrough for slidably receiving an actuating rod 19 secured to the flexible element 14. The shank 16 is fastened to the flexible sheath 13 by means of a short intermediate sheath 20 fastened at one end to the shank and engaging a short length of the sheath 13. Since the intermediate sheath 20 has somewhat less flexibility than the sheath 13, the possibility of bending the sheath 13 at the point of attachment to the fitting 15 is materially reduced. A pair of spaced rods 21 slidably carrying an actuating member 22 are fastened at one end to said fitting 15 and carry a loop assembly 23 at the other end. The actuating member 22 has an opening extending therethrough for receiving the actuating rod 19. The actuating rod 19 is fixed to the actuating member 22 by a set screw 24 so that displacement of the actuating member 22 will move the flexible element 14.

One embodiment of the jaw assembly 12 is illustrated in FIGS. 5 through 10. It essentially includes an elongated sleeve 25 having an opening 26 extending therethrough with one end thereof having an enlarged portion 27 for receiving and holding the distal end of the sheath 13. The outer end of sleeve 25 has a transverse slot 28 for receiving the jaws 29 and 30 as will be described. A trocar assembly 31 includes a cylindrical member 32 having an opening 33 in one end thereof for receiving and holding the distal end of the flexible element 14 and a trocar 34 extending from the other end thereof. The cylindrical member 32 is slidably disposed within the opening 26 of the sleeve 25 so that the axial displacement of the flexible element 14 by operation of the actuator 22 will axially displace the trocar 34. It will be observed in FIG. 5 that the actuating rod 19 has a slot 19' therein to facilitate soldering or otherwise securing the actuating rod 19 to the flexible element 14.

Each jaw 29, 30 includes a generally hemispherical cup portion 35 having a sharpened edge 35', a support 36 having two openings 37 and 38, with the support being offset from the centerline of the jaw so that the support will be on one side of the trocar 34. The jaws also include flattened portions 39 which slidably engage the side edges of the trocar 34. The sleeve 25 also includes two sets of aligned openings 40 and 41 for receiving pins 40' and 41'. The trocar 34 also has an opening 42 for slidably receiving a pin 42'.

The jaws 29 and 30 are assembled to the sleeve 25 by positioning the jaws on each side of the trocar 42 with the openings 38 of each jaw aligned with the opening 42 in the trocar. The pin 42' is then inserted through the openings 38 and 42 to pivot the jaws to the trocar. Since the rearward edge 36' of each jaw is sloped at about 45.degree. the jaws can pivot between open and closed positions as illustrated generally in FIGS. 6 and 10 which also show more clearly the assembly and operation of the jaws.

After the jaws are pivotally attached to the trocar 34, the trocar assembly 31 is inserted in the sleeve 25 until the edges 29' and 30' of the jaws hit against the forward edge of the sleeve 25. In this position the openings 40 in the sleeve 25 will be aligned with the opening 39 in the jaw 29. Similarly the openings 41 in the sleeve 25 will be aligned with the opening 39 in the jaw 30. The pins 40' and 41' are then inserted and slidably engage the openings 39 of the jaws and preferably are press-fit in the cooperating openings 40 and 41. With this arrangement as the trocar assembly is axially displaced by operation of the handle 11, the jaws can be moved between the open and closed positions as seen in FIG. 10.

With specific reference to FIGS. 6 and 10, it will be observed that when the jaws are in the closed position as shown in FIG. 6, the trocar in 34 is retracted and the pointed end thereof will lie just within the outer end of the jaws. When the trocar assembly is displaced forwardly to open the jaws as shown in FIG. 10, the pointed end of the trocar has been displaced outwardly and extends slightly beyond the edges of the open jaws. With this arrangement the trocar can be inserted in a specific tissue area to be sampled and it will tend to retain alignment of the jaws with that specific area so that the desired sample can be extracted.

As previously explained, the edges of the jaws are sharpened to provide peripheral cutting edges 35'. By reason of the improved jaw construction and the mode of operation, the edges of the jaws can be brought into firm contact and thus effect complete severing of a sample. Furthermore, the specific mode of attachment of the jaws to the trocar greatly simplifies assembly and provides a precise and reliable device.

In order to simplify the problem of maintaining sharpened cutting edges, jaw inserts may be utilized as illustrated in FIGS. 11 through 17. Referring more specifically to FIGS. 11 through 14 each jaw 29 and 30 includes an insert 43 and 44 respectively. The insert 43 is shaped to conform with the inner surface of the jaw 29 and has an opening 45 therein which surrounds the opening 46 in the jaw. In the formation of the opening 46, a narrow peripheral lip 47 surrounds the inner edge of the opening 46 so that when the insert 43 is positioned in the jaw, the lip can be swaged outwardly to engage the end of the opening 45 in the insert to hold the latter in place. The insert 44 is similarly secured in position within the jaw 30 by swaging the lip 47' to engage the opening 45' in the insert 44. The outer edge 47 of the insert 43 extends slightly beyond the edge of the jaw 29 and is adapted to be received within the jaw 30 as illustrated more clearly in FIG. 11. The edge 48 of the insert 43 is sharpened as shown more clearly in FIGS. 11 and 14 and the outside diameter of the insert is slightly smaller than the inside diameter of the insert 43 so that it will move within the insert 43. With this arrangement the inserts 43 and 44 can be readily removed and replaced and it avoids the need for frequently resharpening the edges of jaws 29 and 30. While in this embodiment of the invention the inserts are held in place by swaging the lips 47 and 47', it is evident that the inserts may be held in place by silver soldering or other suitable means.

A modified construction of the insert 43 is shown in FIGS. 15 through 17. In this embodiment the insert 49 which corresponds to the insert 43 of FIG. 11 has a helically formed edge 50 so that when the jaws are brought together the cutting edge of the insert 44 produces in effect a slicing action to provide more effective severance of a sample.

In the previous embodiments of the invention, the jaw supports 36 were secured to the trocar 34 by a pin 42' so that as the trocar was displaced axially, the jaws could be moved between their open and closed positions.

A modified mode of effecting operation of the jaws is shown in FIGS. 18 and 19. In this embodiment of the invention the trocar 34' has a pair of spaced openings 51 and 52 into which pins 52 and 54 are press-fit. Each jaw 29 and 30 include semicircular notches 55 and 56. The notch 55 on each jaw is formed on the inner edge 57 of the jaw support 36 which lies in a place substantially parallel with the plane of the jaw edge 35'. Each notch 56 is formed in the inclined edge 58 of each jaw. Since the arcuate spacing of the notches 55 and 56 corresponds precisely with the spacing of the pins 53 and 54, the notches and the pins simulate the operation of a rack and pinion. With this arrangement as the trocar 34' is displaced forwardly as shown in FIG. 18, the pin 53 bears against the forward edges of notches 55 tending to cause the jaws to pivot outwardly. At the same time, the notches 56 move inwardly to engage the pin 54 whereupon the pin 54 will complete the outward motion of the jaws. As the trocar 34' is retracted from the position as shown in FIG. 19, the reverse operation occurs. Inasmuch as the pins 53 and 54 are effectively fixed to the trocar, the assembly of the jaws to the sleeve is greatly facilitated.

While only certain forms of the invention have been illustrated and described, it is understood that alterations, changes, and modifications may be made without departing from the true scope and spirit of the invention.

Claims

What is claimed is:

1. Flexible forceps comprising an elongated flexible tubular member having proximal and distal ends, a flexible element extending through and slidably disposed within said tubular member, the distal end of said tubular member including a jaw assembly comprising a sleeve secured to and extending from the end of said tubular member, a trocar assembly including a cylindrical member slidably disposed within said sleeve and secured to the distal end of said flexible element, a trocar carried by said cylindrical member and extending therefrom, a pair of hollow hemispherical jaws each having a rearwardly extending supporting member, means pivoting the supporting members to said sleeve for movement of the jaws between open and closed positions, means coupling said supporting members to said trocar assembly so that movement of said assembly in one direction will open said jaws and movement in the other direction will close said jaws and means on the proximal end for moving said flexible element relative to said tubular member.

2. Flexible forceps according to claim 1, wherein retraction of said trocar assembly effects closure of said jaws.

3. Flexible forceps according to claim 1, wherein said jaws are provided with cutting edges about the peripheries thereof.

4. Flexible forceps according to claim 1, wherein said jaws each include hemispherical inserts which protrude from the edges of said cups and form cutting edges.

5. Flexible forceps according to claim 1, wherein said jaws each include hemispherical inserts which protrude from the edges of said cups and form cutting edges, the cutting edge of at least one of said cups defining a helix whereby one of said cutting edges slidably engages the other cutting edge to produce a shearing-like cutting action.

6. Flexible forceps according to claim 1, wherein the means coupling the supporting means to said trocar assembly comprises a pin engaging aligned openings in said supporting means and said trocar.

7. Flexible forceps according to claim 1, wherein the means coupling the supporting means to said trocar assembly comprises cooperating engagable elements carried by said supporting means and said trocar assembly.

8. Flexible forceps according to claim 7, wherein said cooperating engagable means comprises pairs of studs extending from opposite sides of said trocar and angularly spaced notches carried by each of said supporting means and positioned equidistant from the first said pivotal means, the notches in each of said supporting means engaging successive studs upon axial movement of the trocar assembly to move said jaws between the open and closed positions.

9. Flexible forceps according to claim 1, wherein said means on the proximal end of said tubular member includes a sleeve-like member having an enlarged end portion secured to said tubular member with the enlarged portion extending outwardly, a pair of spaced rods secured to and extending outwardly of said sleeve-like member, an actuating rod extending through and slidably engaging said sleeve-like member, the last said rod lying between said pair of rods and secured to said flexible element, an actuating element slidably carried by said pair of rods and secured to said actuating rod and a handle secured to the outer ends of said pair of rods.