US3521359A - Dental drill - Google Patents

Description

July 21, 1970 w. H. HARRIS DENTAL DRILL Filed June l0, 1968 United States Patent O 3,521,359 DENTAL DRILL William H. Harris, 4513 S. Pennsylvania, Oklahoma City, Okla. 73119 Filed June 10, 1968, Ser. No. 735,908 Int. Cl. A61c 1 08 U.S. Cl. 32-28 9 Claims ABSTRACT THE DISCLOSURE A dental drill having a head, a drill bit detachably secured in the head, and a handle extending from the head and detachably secured to a plurality of liuid conduits used to convey water and air to the drill. At least one of the uid conduits is connected to the handle through a swivel connection which prevents torque forces from being imparted to the swivelly connected liuid conduit as the handle is twisted about its longitudinal axis by the manipulations of the dentist in drilling.

BACKGROUND OF THE INVENTION Field of the invention This invention relates to dental instruments, and more particularly, to dental drills of the type having one or more uid conduit lines connected to the handle of the drill.

Brief description of the prior art Dental drills now in use are typically provided with one, or more frequently, two iiuid conduits connected to the handle of the drill for supplying air, and usually water, to the head of the drill through tubes which extend through the length of the handle. The fluid conduits are usually rigidly connected to the handle of the drill, and thus turn with the handle as it is manipulated during drilling. In instances where the dentist wishes to change the angle of drilling this is frequently accomplished by rotating the handle of the drill by a wrist action of the dentist. This rotation of the drill handle about its longitudinal axis results in a rotative or torque force being transmitted to the uid conduits attached to the handle, and they become twisted. Since they are conventionally made of a resilient material, this twisting is resiliently opposed by the conduits, and when they are in the twisted state, restorative forces of plastic deformation act constantly to return the conduits to their relaxed, untwisted state. The result is that the wrist of the dentist becomes fatigued over extended periods of drilling, and considerable discomfort is experienced by the dentist. Moreover, the eiiiciency and proficiency of the drilling operation being performed may be detrimentally atfected by such fatigue.

BRIEF DESCRIPTION OF THE PRESENT INVENTION The present invention provides an improved dental drill which enables the dentist to more easily drill over extended periods of time without sustaining fatigue which impairs eliciency and accuracy. Broadly described, the drill comprises a drill handle secured at one end to a drill head which carries a drill bit, and having at least one uid conduit secured to the opposite end of the drill handle through a swivel connection which permits the drill handle to be turned or rotated about its axis without a torque force being imparted to the uid conduit. More specifically, though Without limitation being intended, the invention comprises exible air and water conduits connected to the drill shank or handle, with at least one of these conduits being connected to the handle through a swivel collar which swivelly engages a swivel sleeve which 3,521,359 Patented July 21, 1970 ICC is, in turn, connected to an insert block which is sealingly and detachably connectable to the drill handle. The connection of the insert block to the drill handle is achieved by the use of an internally threaded collar which threads onto an externally threaded end portion of the drill handle.

The described drill structure permits several important objects of the invention to be achieved, including:

(a) making the drill easier to manipulate by the dentist;

(b) increasing the effective service life of the fluid conduits used to convey liuid to the drill; and

(c) reducing wrist and arm fatigue experienced by the dentist during the use of the drill.

In addition to those objects and advantages already described, additional objects and advantages will become apparent as the following detailed description of the invention is read in conjunction with the accompanying drawings which illustrate the invention.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a view in elevation of a dental drill constructed in accordance with the present invention.

FIG. 2 is a view of a portion of the dental drill shown in FIG. l illustrating certain structural elements in section, and certain parts in elevation.

FIG. 3 is a sectional View taken along line 3--3 of FIG. 2.

FIG. 4 is a sectional view taken along line 4-4 of FIG. 3.

FIG. 5 is a sectional view taken along line 5-5 of PIG. 2.

DETAILED DESCRIPTION OF A PREFERRED' EMBODIMENT OF THE INVENTION Referring initially to FIG. l of the drawing, shown therein is a dental drill constructed in accordance with a preferred embodiment of the invention, and designated generally by reference numeral 10. The drill 10 includes a head 12 which contains a chuck or collet which receives the drill bit 14. The drill 10 further includes a handle or shank portion 16 which threadedly engages a collar 18, which functions in a manner hereinafter described to secure to the drill shank 16, an air conduit 20 and a water conduit 22.

One of the salient features of the invention is the manner in which one or both of the air and water conduits 20 and 22 are connected to the drill 10 through a swivel connection which permits the drill to be more easily and ef fectively utilized by the dentist, particularly with respect to a reduction in the fatigue which is experienced by the dentist over a prolonged period of drilling. To impart a better understanding of the manner in which the swivel coupling or connection forming a part of the invention is constructed, it will be helpful to initially describe certain aspects of conventional or typical dental drill construction.

As is generally well known, most dental drills are air driven and, to this end, an air tube 24 is extended through the hollow handle 16 of the drill 10 for the purpose of supplying the air necessary to drive the drill bit 14 in rotation. It is also typical construction in dental drills of this type to supply water to the surface being drilled in order to cool this surface and wash away debris resulting from the drilling. In the drill 10 illustrated in the drawings, a water tube 26 is provided for conveying water to a small jet (not seen) located in the head 12 of the drill. It will be noted in referring to FIG. 2 that the handle or shank 16 of the drill 10 is externally threaded at its end 27 which is threadedly connected to the collar 18, and that, within this externally threaded portion of the handle, the air tube 24 and water tube 26 which extend through the handle project to terminal or end portions which are spaced axially inwardly from the end of the externally threaded portion 27 of the handle 16.

In further description of the typical or conventional dental drill construction, there is provided a conduit connector fitting which is designated generally by reference numeral 30 in the drawings. The conduit connector fittnig 30 includes an insert block 32 of substantially cylindrical cross-sectional configuration, which insert block is dimensioned to fit within the externally threaded end portion 27 of the handle 16 of the drill with sufficient clearance between this portion of the handle and its exterior surface to accommodate in this space a compression cap 34. It will be noted in referring to FIG. 2 that the insert body 32 is provided with an annular flange 36 which extends around the outer periphery thereof, and with a protuberant, generally axially extending, air conduit nipple 38 and a protuberant water conduit nipple 40.

Formed in the end of the insert block 32 which is positioned within the externally threaded end portion 27 of the handle 16 is an air counterbore 42 and a water counterbore 44. These counterbores 42 and 44 communicate respectively with an elongated air bore 46 and water bore 48 which extend coaxially through the air nipple 38 and water nipple 40, respectively. It will further be noted in referring to FIGS. 3-5 that the insert block 32 is provided with diametrically opposed, axially extending grooves 50 which are aligned, and communicate, with air exhaust openings 52 formed in the base 54 of the compression cap 34, as well as with air exhaust passageways 56 which extend through the handle 16 of the drill in proximity to the drill head 12. It will also be noted in referring to FIGS. 2 and 5 that the compression cap 34, in addition to being provided with the air exhaust openings 52 in the base 54 thereof, is also slotted or grooved in diametrically opposed portions of its side wall 60. The air exhaust passageways 56 function to convey air exhausted from the drill turbine away from the area of the drilling, and exhaust such air to the atmosphere. In referring to FIGS. 2 and 3, it will be noted that the axially extending grooves 50 open into the hollow or open interior 58 of the collar 18, so that air is exhausted from the interior of this collar to the atmosphere.

The compression cap 34 carries an annular, radially outwardly extending flange 62 and slides over the insert block 32. The cap 34 retains under compression between its base 54 and the insert block 32, a resilient sealing element 64. The resilient sealing element has a pair of apertures 66 and 68 formed therethrough for sealingly i accommodating the air tube 24 and the water tube 26. The collar 18 is internally threaded for threaded engagement With the externally threaded end portion 27 of the handle 16, and further includes an annular, radially inwardly extending shoulder 70. When the collar 18 is threadedly engaged with the externally threaded end portion 27 of the handle 16 in the manner depicted in FIG. 2, the shoulder 70 bears against the flange 36 of the insert block 32, and forces the insert block inwardly in an axial direction into the threaded end portion 27 of the handle. Since the compression cap 34 is prevented from moving in an axial direction with respect to the handle 16 because of the enga-gement of the flange 62 With the threaded end portion 27, the result of the forced inward movement of the insert block 32 is to compress the sealing element 64. This effects a tight seal around the air tube 24 and the water tube 26.

Pressed over the protuberant air conduit nipple 38 of the insert block 32 is a synthetic resin swivel sleeve 74. The swivel sleeve 74 is retained on the air conduit nipple 38 by a retaining ring 76. At its outer end, the swivel sleeve 74 is provided with an annular flange 78, which flange is swivelly engaged by a swivel collar 80 having inturned flanges 82 which hook over and rotatably interlock with the flange 78 on the swivel sleeve 74 and a if shoulder 83 on a nipple fitting 84. The nipple fitting 84 is provided with a plurality of serrations or ribs 86 which function to frictionally retain the flexible air conduit 20 which has one end thereof pressed over the fitting 84. The filing 84 is provided with an axially extending bore 88 therethrough, which bore is aligned, and in communication, with an axial bore 90 which extends through the swivel sleeve 74 into communication with the bore 46 through the nipple 38. The end of the water conduit 22 is frictionally pressed over the water conduit nipple 40.

OPERATION In assembling or disassembling the dental drill of the invention, disconnection of the handle 16, head 12 and drill bit 14 from the fluid supply lines is eflected by unscrewing the collar 18 from the externally threaded end portion 27 of the handle. When the collar 18 is loosened in this manner, the insert block 32 and the compression cap 34 which is pressed thereover, may be easily withdrawn from the externally threaded end portion 27 of the handle 16. The same procedure, with the steps carried out in reverse order, is utilized when it is desired to connect the air conduit 20 and water conduit 22 to the handle or shank 16 of the drill 10 preparatory to using it for drilling. When the internally threaded collar 18 is connected to the externally threaded end portion 27 of the handle 16 in the manner depicted in FIG. l, the drill is ready for use.

The swivel connection employed in the invention functions to permit the drill to be rotated about the axis of the shank or handle 16 without imparting a twist or torque to the air conduit 20. In other, non-illustrated embodiments, the same may be true of the water conduit 22. As the dentist, in using the drill, finds it necessary to change the angle of drilling by canting or angling the bit 14, this is often accomplished by rotating or twisting the wrist. This motion will in turn cause the handle 16 to be rotated about its axis. This rotational movement is imparted through the insert block 32 to the swivel sleeve 74. The annular flange 78 of the swivel sleeve 74 is free to turn, however, in the inturned flange 82 of the swivel collar 80, so that no torque or twisting movement is transmitted to the air conduit 20 Which is connected to the nipple fitting 84. Thus, the air conduit 20 remains in its relaxed status and is not loaded in resilient deformation. Thus, there is no force stored in the air conduit which acts to constantly oppose the wrist action of the dentist in manipulating the drill, so as to make such manipulation more difficult.

Although a preferred embodiment of the invention has been herein described and is illustrated in the drawings, it will be appreciated that various changes and innovations can be effected without departure from the basic principles which underlie the invention. Changes and innovations of this type are deemed to be included within the spirit and scope of the invention except as the same may be necessarily excluded from the invention by the appended claims or reasonable equivalents thereof.

What is claimed is:

1. A dental drill comprising:

an elongated drill handle;

a drill head secured to one end of said drill handle;

a drill bit rotatably journaled in said drill head;

at least one fluid conduit for conveying fluid to the drill handle;

a swivel sleeve having a bore therethrough and connected to said drill handle, said sleeve having an annular flange thereon positioned concentrically with respect to the bore through said sleeve;

a nipple fitting including a projecting neck portion having a bore extending therethrough, and having an annular shoulder around said neck portion at one end thereof, said neck portion extending into, and frictionally engaging, said one fluid conduit; and

a swivel collar having a first flange engaging the shoulder of said nipple fitting, and having a second llange swivelly engaging said annular llange of said swivel sleeve whereby said sleeve and collar can rotate relative to each other.

2. A dental drill as defined in claim 1 and further characterized to include a conduit connector litting connecting the swivel sleeve to the drill handle, said conduit connector iitting comprising:

an insert 'block having a bore extending therethrough and having a rst portion inserted in said opposite end of the handle;

a ange extending around the outside of said insert block at one end of said lirst portion; and

a nipple concentrically surrounding a portion of the bore in said insert block and projecting into said swivel sleeve; and

a collar threadedly engaging the exterior of the opposite end of said handle and including a shoulder cooperating with the flange of said insert block to force said first portion of said insert block into said opposite end of the handle when said last-mentioned collar is threaded on said handle.

3. A dental drill comprising:

an elongated hollow drill handle;

a drill head secured to one end of said drill handle;

a drill bit rotatably journaled in said drill head;

at least one iluid conduit for conveying a uid to the drill handle;

a swivel connection swivelly connecting at least one of said fluid conduits to the opposite end of said drill handle from said drill head from that to which said drill head is rotatably journaled for avoiding twisting of said swivelly connected conduit when said drill is rotated about the longitudinal axis of said drill handle;

fluid tubes extending lengthwise through said hollow drill handle, and including end portions extending into the hollow interior of said opposite end of said drill handle; and

an insert block detachably engaged with said opposite end of said drill handle and having fluid conveying bores extending therethrough, said block having said swivel connections secured thereto for communication with said iluid tubes through said fluid conveying bores, and said uid conveying bores of said insert block receiving said lluid tube end portions.

4. A dental drill as defined in claim 3 wherein said insert block is further characterized as including:

a ilange extending around at least a portion of the outside thereof and having a diameter larger than the inside diameter of the hollow interior of said opposite end of the handle; and

va collar threadedly engaging the outside of said opposite end of the handle, and engaging the ange of said insert block to retain said insert block seated in the hollow interior of said opposite end of the handle.

5. A dental drill as defined in claim 3 and further characterized to include a compression cap positioned around a portion of said insert block and inside said hollow interior of said opposite end of the handle, said compression cap having a ange extending radially outwardly therefrom, said ange having a larger diametric dimension than the inside diameter of said hollow interior;

a resilient sealing element positioned between said compression cap and said insert block, and surrounding and sealingly engaging said tluid tubes; and

means for moving said insert block toward said sealing element to place said sealing element in compression.

6. A dental drill as delined in claim 4 wherein said swivel connection comprises:

a swivel sleeve having a bore therethrough and connected to said insert block for placing the bore there- 6 through in communication with one of the iluid conveying bores through said insert block, said swivel sleeve having an annular flange thereon positioned concentrically with respect to the bore through said sleeve;

a nipple fitting including a projecting neck portion having a bore extending therethrough, and having an annular shoulder around said neck portion at one end thereof, said neck portion extending into, and frictionally engaging, said one fluid conduit; and

a swivel collar having a first flange engaging the shoulder of said nipple litting, and having a second ilange swivelly engaging said annular flange of said swivel sleeve whereby said sleeve and collar can rotate relative to each other.

7. A dental drill as defined in claim 6 and further characterized to include:

a compression cap positioned around a portion of said insert block and inside said hollow interior of said opposite end of the handle, said compression cap having av ange extending radially outwardly therefrom, said tlange having a larger diametric dimension than the inside diameter of said hollow interior;

a resilient sealing element positioned between said compression cap and said insert block, and surrounding and sealingly engaging said fluid tubes; and

means for moving said insert block toward said sealing element to place said sealing element in compression.

8. A dental drill comprising:

an elongated drill handle;

a drill head secured to one end of said drill handle;

a drill ybit rotatably journaled in said drill head;

at least one fluid conduit for conveying a fluid to the drill handle;

a swivel connection swivelly connecting at least one of said iluid conduits to the opposite end of said handle from said drill head and for avoiding twisting of said swivelly connected conduit when said drill is rotated about the longitudinal axis of said drill handle;

uid tubes extending lengthwise through said handle;

and

an insert block detachably engaged with said opposite end of said handle and having iluid conveying bores extending therethrough, said block comprising:

an air conduit nipple projecting from the opposite side thereof from said handle and into said swivel connection; a water conduit nipple projecting from the opposite side thereof from said handle; and a Water conduit connected to said water conduit nipple. 9. A dental drill comprising: an elongated drill handle; a drill head secured to one end of said drill handle; a drill bit rotatably journaled in said drill head; at least one uid conduit for conveying iluid to the drill handle; a nipple litting having a bore therethrough and an annular shoulder thereon concentric to said bore; va swivel sleeve having a bore therethrough and connected to said drill body, said sleeve having a ange therearound concentric to the bore therethrough; and

a collar swivelly interconnecting said sleeve and nipple -ftting and placing the bores of said nipple litting and sleeve in communication with each other.

References Cited UNITED STATES PATENTS ROBERT PBsHocK, Primary Examiner

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