US3367727A - Oral surgery tool with interchangeable blades - Google Patents

Description

6, 1968 A. w. WARD ETAL 3,367,727

ORAL SURGERY TOOL WITH INTERCHANGEABLE BLADES g filin m mm m. w

Filed Oct. 22, 1965 FIGI e T k A TTTORNEKS.

United States Patent Ofiiice 3,367,727 Patented Feb. 6, 1968 3,367,727 ORAL SURGERY TOOL WITH INTER- CHANGEABLE BLADES Abraham W. Ward, 1125 Greenwich St., San Francisco, Calif. 94109, and Raymond T. Whipple, 673 Bille Road, Paradise, Calif. 95969 Filed Oct. 22, 1965, Ser. No. 501,517 4 Claims. (Cl. SOS-28) ABSTRACT OF THE DISCLOSURE A tool for oral surgery is disclosed as including a handle having a longitudinally extending outwardly opening recess, a replaceable tool having a shank fitting the recess, and releasable detent means for anchoring the shank in the recess or permitting withdrawal of the shank from the recess. The recess has at least one aperture through its wall, receiving a ball detent whose diameter is greater than the thickness of the recess wall. A sleeve is reciprocable longitudinally of the handle and has an annular groove alignable with the recess or recesses. The combined depth of the annular groove and the thickness of the recess wall is at least equal to the diameter of the ball detent so that the ball detent may move outwardly into the annular groove to clear the recess when the annular groove is aligned with the recess. The tool shank may then be inserted into the recess and, by longitudinal displacement of the sleeve along the handle, the annular groove is moved out of alignment with the aperture in the recess wall so that the ball detent is forced inwardly to engage locking formations on the shank of the tool.

Background of the invention This invention relates to surgical tools, particularly to knives designed for oral surgery as in operations on the gums for the treatment of pyorrhea or similar conditions. More particularly, the present invention is directed to a novel oral surgery tool in which interchangeable blades maybe readily engaged into and disengaged from a common handle.

In a particular type of knife to which the present invention is directed, and which is particularly designed for oral surgery, the knife blade preferably is arranged in angular or oblique relation with respect to the longitudinal axis of its handle, thereby enabling the blade to be used most effectively for operations upon the gum. In its preferred form, the blade is provided with a single bevelled cutting edge, the inside surface of the blade being a planar surface, and the outer side of the blade being smoothly bevelled so that the cutting edge is coincident with the inner planar surface. This enables the blade to be sharpened very easily by applying the planar surface to a sharpening stone.

The cutting edges of these knives become worn during use, and also are sometimes broken or otherwise damaged. Consequently, in order not to interrupt an oral surgery, it is necessary that spare or extra knives be kept on hand, so that, in the event of excessive wear or damage of the knife being used, a freshly sharpened knife may be substituted. As a result, the dentist has a substantial investment tied up in spare knives.

Summary 07 the invention To avoid this, the present invention comprises a novel oral surgery tool wherein knife blades may be readily interchanged in a common handle. Thereby, the only in- 1y as possible, particularly when the dentist is actually in the course of oral surgery. The present invention provies for such quick interchange by providing a novel, easily operable chuck or clutch by means of Which one blade may be rapidly and simply disengaged from the handle and a new blade firmly locked therein without any loss of time.

To this end the handle has, at one end, a longitudinally extending outwardly opening recess, and each tool has a shank fitting in the recess. In a preferred embodiment of the invention, the shank is formed with at least one tapered indentation extending therealong, decreasing in depth toward the free end of the shank and terminating short of the free end thereof. An aperture is formed through the wall of the recess and is aligned with the indentation in the shank when the shank is operatively engaged in the recess, and a ball detent is displacea-bly mounted in the aperture and has a diameter greater than the thickness of the recess wall.

A sleeve closely embraces the outer surface of the recess wall and is displaceable longitudinally of the handle. This sleeve has an annular groove in its inner surface alignable with the aperture, and the thickness of the recess wall plus the depth of the annular groove is at least equal to the diameter of the ball detent. Thus, when the annular groove is aligned with the aperture, the shank may be inserted into and retracked from the recess with the ball detent retracted into the annular groove to clear the recess. Upon relative longitudinal displacement of the sleeve to displace the annular groove out of alignment with the aperture, the ball detent is displaced into the indentation in the shank to lock the shank in the recess.

A feature of the invention is that the shank has laterally projecting shoulders spaced from its free end and engageable with the sleeve, upon displacement of the sleeve in a shank locking direction towards the shank and outwardly of the recess, to effect relative movement of the ball detent toward the shallower portion of the ball detent and the indentation in the shank, with the net effect being what might be termed a double camming action.

Description of the drawings For an understanding of the invention, reference is made to the following description of two embodiments thereof which are illustrated in the accompanying drawings, with FIGS. 1 through 4 illustrating one embodiment, and FIGS. 5 through 8 illustrating a second embodiment.

in the drawings:

FIG. 1 is an exploded partial perspective view of one form of oral surgery knife embodying the invention;

FIG. 2 is a part elevation and part longitudinal sectional view of the operative end of the knife in FIG. 1, showing the clutch parts in the release portion;

FIG. 3 is a view similar to FIG. 2, illustrating the clutch parts in the locking position;

FIG. 4 is a partial elevation view corresponding to FIG. 3;

FIG. 5 is a view, similar to FIG. 1, illustrating a second embodiment of oral surgery tool in accordance with the invention;

FIGS. 6 and 7 are views, corresponding respectively to FIGS. 2 and 3, of the second embodiment of the oral surgery tool; and,

FIG. 8 is a section taken on the line 3-8 of FIG. 7.

Description. of the preferred embodiments Referring first to that embodiment of the tool shown in FIGS. 1 through 4,tool 15 is illustrated as including aknife blade 10 and a relatively elongated and substantiallyrectilinear handle 20.Blade 10 is preferably formed of sheet steel and is mounted so that the edged portion extends at an angle of approximately 45 to the longitudinal axis ofhandle 20. Blade has a somewhatwidened edge portion 11 which extends at substantially a right angle to anintermediate portion 12 which, in turn, extends at an angle of approximately 45 to a shank portion generally indicated 13. Intermediate the ends ofshank portion 13, the side edges of the latter are flared outwardly to form a pair of oppositely extendingshoulders 14 which face toward the inner end of the shank portion. Inwardly ofshoulders 14,shank portion 13 is substantially narrow and rectangular, as indicated at 1.6, and is formed with a preferablycircular aperture 17 for a purpose to be described. Thisnarrow shank 16, in cooperation with theshoulders 14, is arranged to form the operative interlocking connection betweenblade 10 and handle 20.

Handle 20 is preferably a solid piece of metal which is relatively rigid and relative.y massive in order to provide for adequate control of the knife. To provide for easy gripping of thehandle 20, the latter preferably has a polygonal cross section, such as the hexagonal cross section illustrated. One end ofhandle 20 is formed with wall means defining a longitudinally extending recess which receives thenarrow shank 16 ofblade 10. As illustrated, this end ofhandle 20 has a substantiallyconical transition section 21 connecting agrip portion 22 to a reduced diameter extension generally indicated at 23. For a purpose to be described,extension 23, over a relatively minor portion of its length, is formed with athread 24. The aforementioned recess is formed by a substantially rectangularcross section slot 25 extending inwardly from the outer end ofextension 23 and terminating somewhat outwardly of the outer end ofthread 24. This slot is defined laterally by wall means 26, 26 having a preselected thickness.

Intermediate the inner and outer ends ofrecess 25, and preferably near the inner end thereof, one or both of the wall means 26 are formed with a preferablycircular aperture 27 therethrough. The particular embodiment of the invention illustrated in the drawing, this aperture receives a detent member which is in the form of aball 30. The diameter, or lateral dimension ofball 30, is somewhat greater than the thickness of wall means 26. The purpose of this will be made apparent as the description proceeds.

A relatively elongated and internally threadedsleeve 31 closely embraces theextension 23 and the wall means 26, and has a length only a little less than that ofextension 23. The outer surface ofsleeve 31 is knurled as at 32 (FIGS. 1 and 4) to provide for firm gripping thereof. Adjacent itsouter end sleeve 31 is reduced in outer diameter in a smooth transitional manner, as indicated at 33. Adjacent this transition portion, the inner surface ofsleeve 31 is formed with a relatively shallow arcuate cross sectionannular groove 35. The depth ofgroove 35 plus the thickness of a wall means 26 has a value at least equal to the diameter of balldetent member 30, and may slightly exceed this diameter.

Thetool 15 shown in FIGS. 1 through 4 is operated in the following manner: In order to insert thenarrow shank 16 of ablade 10 into therecess 25,sleeve 31 is screwed inwardly alongthread 24 untilarcuate groove 35 is aligned withaperture 27. When this alignment is effected, theshank 16 of theblade 10 may be readily inserted intorecess 25, with ball detent member being forced laterally or radially outwardly to engage inarcuate groove 35. Shank 16 is pushed inwardly intorecess 25 sufficiently to align theaperture 17 in the shank with theaperture 27 in wall means 26, and preferably this occurs when the inner end ofshank 16 is either at or closely adjacent the bottom end ofrecess 25. Ifsleeve 31 is now screwed outwardly alongreduced diameter extension 23, from the position shown in FIG. 2 to the position shown in FIG. 3, ball detent member 36 will be forced inwardly to engage in aperture orrecess 17. Preferably, such outward screwing ofsleeve 31 alongthread 24 is continued until the outer end ofsleeve 31 abuts theshoulders 14 ofblade 10, and thus these shoulders limit the outward displacement ofsleeve 31.Blade 10 is now firmly locked inhandle 20. T 0release blade 10 for interchange with another blade,sleeve 31 is screwed inwardly until arcuate groove is again aligned withaperture 27. If a retracting force is then exerted onblade 10, theshank 16 of the latter may be readily withdrawn fromrecess 25, forcingball detent member 30 to move intoarcuate groove 35.

It should be appreciated that, instead of formingshank 16 with anaperture 17, the shank may have another type of formation which is cooperable with ball detent member 39 to lock the shank inrecess 35. For example, shallow dimples or recesses may be formed in the wider surfaces ofshank 16.

FIGS. 5 through 8 illustrate a second embodiment of tool in accordance with the invention, and thetool 15 shown in these figures includes ablade 40 having a circular or cylindrical shank and arranged to be releasably and interchangeably interlocked in ahandle 45. Theblade 40 may be either an oral surgery knife or any other type of tool, and is operated and may have the same construction as the operative end of theblade 10 of FIGS. 1 through 4. Blade 44) includes acylindrical shank 41 with a reduceddiameter extension 42. The end ofextension 42 is formed as a latching portion. For this purpose, the inner end ofextension 42 is formed with two or more planar bevelled surfaces 43, each terminating in aradial shoulder 44. In the particular embodiment shown, there are three of these bevelledsurfaces 43, as best illustrated in FIG. 8. Thus, a diametrical section through the latching end ofextension 42 has the shape of a triangle with rounded corners.Shoulders 44 face toward the inner end ofextension 42, andbevelled surfaces 43 increase in depth outwardly from this inner end, as best seen in FIGS. 6 and 7. The major portion ofhandle 45 is identical with the corresponding major portion ofhandle 20 of FIGS. 1 through 4. Thus, handle 45 has a polygonal cross section and relativelyelongated grip 46 which merges, through atransitional portion 47, with a reduceddiameter extension 48. However, instead of being formed with a rectangular cross section slot orrecess 25, as in the case ofhandle 20, the reduceddiameter extension 48 ofhandle 45 is formed with acylindrical recess 50. The external surface ofextension 48 is formed with athread 49 which extends fromadjacent transition portion 47 to a point somewhat outwardly of the inner end ofrecess 50.Recess 50 is defined by tubular or annular wall means 51 which have a predetermined thickness, and wall means 51 is formed with a plurality of preferably circular apertures therethrough equal in number of the bevelled surfaces 43 and preferably spaced at equal angular distances circu-mferentially of wall means 51. Each of theapertures 52 receives aball detent member 55 which has a diameter somewhat greater than the thickness of wall means 51. While ball detent members are illustrated by way of example, it should be appreciated that the detent members could have forms other than spherical, such as, for example, cylindrical cross section or rectangular cross section pin shapes. In such latter case, the dimensions of the detent members laterally of wall means 51 will be somewhat in excess of the thickness of wall means 51.

Anouter sleeve 56 has a relativelylarge diameter portion 57 which closely embracesextension 48 ofhandle 45, and a relativelysmall diameter section 58 which is arranged to closely embraceextension 42 ofshank 41 of blade ortool 40. A short distance from the inner end ofsleeve 56, the inner surface oflarge diameter portion 57 is formed with an arcuate cross sectionannular groove 60.

Aninner sleeve 61 is internally threaded for engagement with thethread 49 onhandle extension 48, and the length ofsleeve 61 is somewhat less than the axial length ofthread 49. The outer surface ofsleeve 61 is knurled,

as best seen at 62 in FIG. 5, to provide for sure gripping thereof.

The arrangement shown in FIGS. through 8 operates substantially as follows: With the parts occupying the position shown in FIG. 6, theinner sleeve 61 has been screwed in inwardly along thethread 49 so that theouter sleeve 56 may be displaced inwardly to align arcuateannular groove 60 withaperture 62. This permits theball detent members 55 to clear therecess 50. Theextension 42 ofshank 41 ofblade 40 may then be inserted into the recess for the full depth.Outer sleeve 56 is then moved outwardly until its small diameter portion 53 abuts the shoulder at the intersection ofextension 42 with the main portion ofshank 41. Assleeve 56 is moved outwardly, theball detent members 55 are forced into the bevelled surface recesses 43 to lockextension 42 against disengagement fromrecess 50. Theinner sleeve 61 is threaded outwardly to abut theouter sleeve 56 and maintain the latter fully engaged with the shoulder betweenshank 41 andextension 42. Release of a blade or tool for interchange with another blade or tool for other purposes is efiected by the reverse of these movements.

While specific embodiments of the invention have been shown and described in detail to illustrate the application of the principles of the invention, it will be understood that the invention may be embodied otherwise without departing from such principles.

What is claimed is:

1. A tool for oral surgery comprising a handle having, at one end, wall means defining a longitudinally extending recess; a replaceable tool having a shank fitting in said recess; said shank being formed with a tapered indentation extending therealong, decreasing in depth toward the free end of said shank, and terminating short of said free end; an aperture formed laterally through said wall means and opening into said recess, said aperture being aligned with the deeper portion of said indentation when said shank is operatively engaged in said recess; a ball detent displaceably mounted in said aperture and having a diameter greater than the thickness of said wall means; and a sleeve closely embracing said wall means and relatively displaceable longitudinally of said handle, said sleeve having an annular groove in its inner surface alignable with said aperture by longitudinal displacement of said sleeve; the thickness of said wall means plus the depth of said groove being at least equal to the diameter of said ball detent; whereby, when said groove is aligned with said aperture, said shank may be inserted into and retracted from said recess with said ball detent retracted into said groove to clear said recess, said ball detent, upon relative longitudinal displacement of said sleeve to displace said groove from alignment with said aperture, being displaced into said indentation to grip said shank to lock the same against retraction from said recess; said shank having laterally projecting shoulders spaced from its free end and engageable with said sleeve, upon displacement of said sleeve in a shank locking direction to urge said shank outwardly of said recess to eiiect relative movement of said ball detent toward the shallower portion of said indentation, to exert a further gripping action between said ball detent and said indentation.

2. A tool for oral surgery comprising a handle having, at one end, wall means defining a longitudinally extending substantially circular cross section recess; a replaceable tool having a circular cross section shank fitting in said recess, the inner end of said shank being formed with plural tapered indentations extending longitudinally thereof, in the same zone and arranged at equal angular spacings around said shank, and decreasing in depth to- 7 ward the free inner end of said shank and terminating short of said free inner end; at least one aperture formed laterally through said wall means and opening into said recess, said aperture being aligned with one of said indentations when said shank is operatively inserted in said recess; a detent ball displaceably mounted in said aperture and having a diameter greater than the thickness of said wall means; sleeve means closely embracing said wall means and relatively displaceable longitudinally of said handle, said sleeve means having an annular groove in its inner surface alignable with said aperture by longitudinal displacement of said sleeve means; the thickness of said wall means plus the depth of said groove being at least equal to the diameter of said detent ball; whereby, when said groove is aligned with said aperture, said shank may be inserted into and retracted from said recess with said ball detent retracted into said groove to clear said recess, said ball detent, upon relative longitudinal displacement of said sleeve to displace said groove from alignment with said aperture, being displaced into said recess to engage in one of said indentations to grip said shank to lock the same against retraction from said recess; said shank having a shoulder thereon facing toward said inner end and engageable with said sleeve means, upon such longitudinal displacement thereof in a direction to displace said groove from alignment with said aperture to urge said shank outwardly of said recess to eifect relative movement of said ball detent toward the shallower portion of said indentation to exert a further gripping action between said ball detent and said indentation.

3. A tool for oral surgery, as claimed in claim 2, in which said wall means comprises a first sleeve reciprocable on said wall means for longitudinal displacement relative thereto; a second sleeve closely embracing said wall means and relatively displaceable longitudinally of said handle, said second sleeve having said annular groove; said second sleeve having an outer end engageable with said shoulder on said shank and having an inner end engageable with an end of said first sleeve for displacement of said second sleeve by movement of said first sleeve along said handle equal to the diameter of said ball detent; whereby, when said groove is aligned with said aperture, said shank may be inserted into and retracted from said recess, with said ball detent retracted into said groove to clear said recess; said ball detent, upon relative longitudinal displacement of said second sleeve by rotation of said first sleeve to displace said groove from alignment with said aperture, being displaced into said recess to engage one of said indentations to grip said shank to lock the same against retraction from said recess.

4. A tool for oral surgery as claimed in claim 2, in which said wall means is formed with a plurality of apertures opening into said recess, said apertures being arranged in the same zone and at equal angular spacing around said wall means and each aperture being aligned with a respective one of said indentations when said shank is operatively inserted in said recess; each aperture having a ball detent displaceably mounted therein.

References Cited UNITED STATES PATENTS 1,341,934 6/1920 Schoenborn 279-81 2,47 2,392 6/ 1949 Alexander 279- 2,491,605 12/ 1949 Crittendon 27982 2,736,561 2/1956 Hansen 279-76 2,736,562 2/ 1956 Blackburn 27976 CARL W. TOMLIN, Primary Examiner.

WAYNE L. SHEDD, Assistant Examiner.

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