US2897596A

US2897596A - Fluid-driven dental handpiece construction

Info

Publication number: US2897596A
Application number: US707059A
Authority: US
Inventors: John A Maurer
Original assignee: Weber Dental Manufacturing Co
Current assignee: Weber Dental Manufacturing Co
Priority date: 1958-01-03
Filing date: 1958-01-03
Publication date: 1959-08-04
Anticipated expiration: 1976-08-04

Description

Aug. 4, 1959 J. A. MAURER 1 2,897,596

FLUID-DRIVEN DENTAL HANDPIECE CONSTRUCTION Filed Jan. 3, 1958 IN V EN TOR.

JohnAMwwrer HTTOHVEYS "mired St FLUID-DRIVEN DENTAL HANDPIECE CONSTRUCTION Application January 3, 1958, Serial No. 707,059

8 Claims. (CI. 3227) My invention relates generally to improvements in fluid-driven dental handpiece construction and more specifically to the means for mounting the fluid-drlven turbine contained in such a handpiece. Furthermore the present invention is an improvement on the construction disclosed in a copending application Serial No. 618,325, filed October 25, 1956 and of which I am a coinventor.

The fluid-driven dental handpiece construction (118-- closed in the above referred to copending application includes an elongated handle having a fluid supply and exhaust portion formed at one end thereof and a turbine or rotor casing formed at the other end, with this turbine or rotor having burr holding means directly connected therethrough and rotatable therewith for mounting and rotating a conventional dental burr tube used for drilling teeth. Further this prior handpiece includes conduit means extending from the fluid supply and exhaust section lengthwise through the elongated handle and being connected to a nozzle or other means for directing a jet or stream of the fluid, such as air, toward the turbine. In this manner the turbine is rotated, and this fluid is then exhausted from the turbine around the nozzle and lengthwise back through the handle around the fluid supply conduit.

After the fluid reaches the fluid supply and exhaust section of the handpiece, after traveling lengthwise through the handle from the turbine, when the fluid used is air, it can be exhausted into the atmosphere. As disclosed in this copending application, in order to minimize the noise caused by this fluid exhausting into the atmosphere, and also to aid in mufliling the noise of the fluid striking the turbine and exhausting from the turbine, it was necessary to provide a rather complicated mufller construction at the supply and exhaust section of the handpiece, which mufiler construction is not only somewhat cumbersome but is also rather expensive to manufacture.

Without this mufller construction, however, it has been found that the noise created by this fluid exhausting from the handpiece and particularly the noise created by the fluid circulating in and around the turbine is extremely objectionable and in fact prohibitive, both from the standpoint of the dentist using the handpiece and the patient whose teeth are being drilled. Also a great amount of noise is created by the bearings which mount the turbine for rotation, and all of these factors are even more apparent when it is considered that this turbine is capable of rotating at speeds in the order of between 100,000 and 200,000 revolutions per minute.

According to the principles of the present invention, however, it has been found that the rather complicated muffler construction used at the supply and exhaust section of the handpiece can be eliminated merely by mounting the turbine and turbine bearings within the turbine casing by special insulating or muifling means, with the shape and particular relationship of this muflling means es Patent to the turbine being of the utmost importance. Furthermore it has been found, with the special muifling means being provided for mounting the turbine and turbine bearings and thereby substantially eliminating any great amount of noise being created at the turbine end of the handpiece by the bearings rotating at these extremely high operating speeds and the fluid striking and circulating around the turbine, that the noise created by the fluid exhausting at the supply and exhaust section of the handpiece is not excessive nor objectionable.

It is, therefore, a general object of the present invention to provide a fluid driven dental handpiece construction in which the noise of operation thereof is greatly reduced and is not objectionable to the dentist using the handpiece or his patients.

It is a primary object of the present invention to provide a fluid driven dental handpiece construction in which novel mounting means is used for mounting the fluid turbine and the bearings thereof in the turbine casing to thereby decrease the noise of operation of the turbine.

It is also an object of the present invention to provide a fluid driven dental handpiece construction in which the novel means for mounting the fluid turbine and bearings thereof in the turbine casing not only muflles the noise created by these bearings but also serves as a muflie for fluid such as air being deflected from the turbine or escaping from the turbine during the rotation thereof which would normally strike the turbine casing.

Finally it is an object of the present invention to provide a fluid driven dental handpiece construction which satisfies all of the above objects in a simple and eflicient manner and reduces the manufacturing cost thereof below that heretofore possible.

These and other objects are accomplished by the parts, constructions, arrangements, combinations and subcombinations comprising the present invention, the nature of which is set forth in the following general statement, a preferred embodiment of which-illustrative of the best mode in which applicant has contemplated applying the principles-is set forth in the following description andillustrated in the accompanying drawings, and which is particularly and distinctly pointed out and set forth in the appended claims forming a part hereof.

In general terms the improved fluid driven dental handpiece construction comprising the present invention may be stated as including an elongated handle member having a turbine casing mounted at one end thereof, with this turbine casing having a generally cylindrical bore formed therein for reception and mounting of a fluid turbine assembly. The fluid turbine assembly is comprised of a fluid driven turbine preferably mounted for rotation by bearing means at either end thereof.

Further according to the principles of the present invention, the turbine assembly also includes a plastic sleeve surrounding the outer circular peripheries of the turbine and bearing means with this plastic sleeve extending completely across the outer peripheries of the turbine and bearing means and being free of openings at said outer peripheries except at the point of connection between the turbine casing and the elongated handle of the handpiece. Finally the construction includes means for supplying fluid to the turbine for rotating the same and exhausting fluid therefrom, and also means operably connected to the turbine for mounting a dental burr tube rotated by the turbine.

By way of example, an embodiment of the fluid driven dental handpiece construction of the present invention is illustrated in the accompanying drawings forming a part hereof, wherein like numerals indicate similar parts throughout the several views, and in which:

Fig. 1 is a fragmentary vertical section, part in eleva- 3 tion, looking in the direction of the arrows 11 in Fig.

Fig. 2 a fragmentary sectional View, part in elevation, looking in the direction of the arrows22 in Fig. 1;

Fig. 3asectional view, part in elevation, looking inthedirection of the arrows 3'3 in Fig. l; and

Fig. 4 a sectional view, part in elevation, looking in the direction of the arrows 44 in Fig. 1- with the turbine assembly and turbine casing caps removed.

The fluid driven dental handpiece construction comprising the present invention in general construction is preferably similar to the construction disclosed in the copending applicaiton Serial No; 618,325 referred toabove with addition of the novel construction as herein disclosed and claimed; The main exceptions to this are that. the muffler construction at the fluid supply and ex haust section of this prior construction iseliminated and a conventional coolant attachment is provided in the present construction mounted on'the outer periphery of the handle as will be hereinafter described in detail; Other slight difierences will be apparent from the following description.

Referring to the drawings and particularly Fig. 1, the fluid driven dental handpiece construction of the present invention includes a handle member, generally indicated at 10, having a turbine casing, generally indicated at' 11, attached thereto, with this turbine casing enclosing and mounting a turbine assembly, generally indicated at 12. Still further, the construction preferably includes a conventional coolant spray attachment, generally indicated at 1-3, and a fluidsupply and exhaust section (not shown) at the end of the handle member 10 opposite from the turbine casing 11.

The handle member 10 is preferably cylindrical and hollow and has. a resilient material fluid supply tube 14 extending lengthwise therethrough from the supply and exhaust section to the nipple 15 of the fluid directing means 16, which directing means is also enclosed by the handle. member 16 adjacent the turbine casing 11. The fluid directing means 16 is also preferably generally cylindrical and is preferably received in handle member- 10 in proper position by a press fit.

Further this directing means includes a' nozzle portion 17 for directing fluid. in a specific manner and at a specific location. toward the turbine assembly 12 in the turbine casing 11, and also this directing means is provided with a cutout portion extending the complete length along one side thereof. This cutout portion forms, with the'handle member 10, an exhaust conduit 18 forreceiving fluid exhausted from the turbine assembly 12 and for transmitting this exhaust fluid back through the handle member 10 and ultimately around the fluid supply tube 14- to the supply and exhaust section. Finally the handle member 10 is provided with the connection assembly, generally indicated at 19, intermediate the ends thereof, which may be selectively released for changing the position of the turbine casing 11 with reference to the main, portion of this handle member.

It is also preferred to provide the conventional coolant spray attachment 13 mounted on the handle member 18' by the clip 2%. This attachment includes the coolant supply tube 21 connected to the coolant directing nozzle 22, as shown.

The turbine assembly generally indicated at 12 includes the turbine 23, the

bearings

24 and 25 and, according to the principles of the present invention, the muffle sleeve 26. Further turbine 23. may be formed integral with the burr holder, generally indicated at 27, which holder includes the collet 28. Burr holder 27 may also be formed centrally through turbine 23 and

bearings

24 and 25, as shown, and serves the purpose of holding the dental burr so that holder 27 and the burr may be rotated bythe turbine 23.

Turbine 23 may be provided with impelling means such as the turbine buckets 29'spaced around he outer peripheries thereof in radial alignment with the nozzle portion 17 of the fluid directing means 16. Further turbine 23 is rotatably mounted within the turbine casing 11 by means of the

bearings

24 and 25 with these bearings being mounted at opposite ends of the turbines surrounding portions thereof andaxially outward of the turbine buckets 29. 4

Bearings 24' and 25 are in turn mounted in the 'bore 30 of the turbine casing 11 by means of the muffle sleeve 26 with this sleeve surrounding the bearings and also surrounding the outer periphery of the turbine 23 except at the point of connection of the turbine casing 11' to the handle member 10. Thus, as shown, bearings 24 and 25' are pressed over the end portions of'the turbine 23 and this assembly of turbineandbearings is encased with the muflie sleeve 26. Still further, this entire assembly is mounted in the turbine casing 11 by a press fit.

It is important to point out that, with this construction of turbine 23,

bearings

24 and 25 and muifle sleeve 26, the only mounting connection between the bearings and the turbine, casing 11 is through the thickness of the muflle sleeve. Furthermore it is important to point out that the muflie sleeve 26 extends completely between

bearings

24 and 25, around the outer periphery of the turbine 23, except at the point where the turbine casing 11 is connected to the handle 10, atwhich point the mutfle sleeve must be removed in order to permit the turbine 23 to receive fluid from the nozzle portion 17 of the fluid directing means 16 and to permit the turbine to exhaust fluid therefrom into the exhaust conduit 18.

Finally the turbine casing 11 is provided at its upper end, adjacent the upper end of the muflie sleeve 26, with cap 31 threadably received therein closing this upper end; Also the lower end is enclosed by a cap 32 received bya press fit in this lower end abutting the lower end of the muffle sleeve 26 and surrounding the lowerend of the burr holder 27.

In order for the muflle sleeve 26 to perform its function of reducing the noise caused by the rotation of turbine 23 and

bearings

24 and 25, and the noise created by the fluid striking the turbine and deflecting therefrom toward the turbine casing 11, it is necessary that this sleeve have a certain degree of resiliency. Further, in order to retain the turbine and bearings properly mounted within the turbine casing,it is also necessary that this sleeve be of suflicient body to retain the press fit between the

bearings

24 and 25 and the turbine casing 11.

One type of material that has been found particularly effective for this purpose is the class of materials known as memory plastics. The most effective of these materials wh-ich has thus far been found is one commercially known as Teflon which is apolymerized tetrafluoroethylene composition, and it is believed that certain other of the memory plastics may be just as effective.

Thus this resilient plastic muffle sleeve insulates the

bearings

24 and 25 from the turbine casing 11 thereby preventing any vibrations from passing between these hearings and the turbine casing. Further, and just as important, is the fact that the muflie sleeve 26 also extends between the bearings and around the outer periphery of the turbine 23 so that any fluid being deflected from this turbine, which is rotating at an extremely high rate of speed, does not strike the surface within the turbine casing bore 30, but rather strikes the muffle sleeve 26 which. again insulates and prevents any noisev from being created .by this deflected fluid.

Thus, according to the principles of the present invention, a fluid driven dental handpiece construction is provided in which the noise normally created by the bearings mounting the turbine and also the noise normally created by the fluid striking the turbine and being deflected therefrom is eifectively reduced, with this being accomplished' in a simple and efficient manner at a minimum expense and without requiring any bulky attachments to the handpiece.

In the foregoing description, certain terms have been used for brevity, clearness and understanding, but no unnecessary limitations are to be implied therefrom, because such words are used for descriptive purposes herein, and are intended to be broadly construed.

Moreover, the embodiment of the improved construction illustrated and described herein is by way of example, and the scope of the present invention is not limited to the exact details of the construction shown.

Having now described the invention, the construction, operation and use of a preferred embodiment thereof, and the advantageous, new and useful results obtained thereby; the new and useful construction and reasonable mechanical equivalents thereof obvious to those skilled in the art are set forth in the appended claims.

I claim:

1. Fluid-driven dental handpiece construction including an elongated handle having an end portion, a turbine casing connected to said handle end portion, plastic sleeve means mounted coaxially in said turbine casing, a turbine having a longitudinally extending peripheral surface having impelling means formed therein, bearing means rotatably mounting the turbine in the plastic sleeve means and coaxially with said sleeve means, said sleeve means surrounding said bearing means between said bearing means and the turbine casing and extending over the peripheral surface of the turbine between said surface and said turbine casing for insulating the bearing means from said casing and deflecting fluid escaping from the turbine impelling means which would normally strike the casing, means for supplying fluid to the turbine for rotating said turbine, means for exhausting fluid from the turbine, and means operably connected to the turbine for holding a dental burr.

2. Fluid-driven dental handpiece construction as defined in claim 1 in which the turbine has end portions at opposite ends of said peripheral surface; in which the bearing means includes a bearing mounted at each end portion of the turbine; in which the turbine peripheral surface and impelling means is positioned between said bearings; and in which the plastic sleeve means surrounds each of said bearings between the bearings and the turbine casing and extends longitudinally between said bearings over the turbine peripheral surface and impelling means.

3. Fluid-driven dental handpiece construction as defined in claim 1 in which the handle has a longitudinal axis; in which the turbine casing has a longitudinal axis; in which the turbine casing is connected to the handle with the longitudinal axes of said casing and handle extending substantially perpendicularly to each other; in which the plastic sleeve means has an opening formed therein at said connection of the handle and casing; in which the means for supplying fluid to the turbine and the means for exhausting fluid from the turbine extend 6 through the handle and communicate with the turbine from said handle into the turbine casing through the plastic sleeve means opening; and in which the means for holding a dental burr is connected to the turbine substantially aligned with said turbine casing longitudinal axis.

4. Fluid-driven dental handpiece construction as delined in claim 1 in which the plastic sleeve means is formed from a memory plastic.

5. Fluid-driven dental handpiece construction as defined in claim 4 in which the memory plastic is a polymerized tetrafluoroethylene composition.

6. Fluid-driven dental handpiece construction including an elongated handle having an end portion and a longitudinal axis, a turbine casing having a longitudinal axis and being connected to said handle end portion with the longitudinal axes of said casing and handle extending substantially perpendicularly to each other, plastic sleeve means mounted coaxially in said turbine casing, said plastic sleeve means having an opening formed therein at said connection of the casing and handle, a turbine having a longitudinally extending peripheral surface having impelling means formed therein, the turbine having end portions at opposite ends of said peripheral surface, a bearing mounted at each end portion of the turbine and rotatably mounting the turbine in the plastic sleeve means and coaxially with said sleeve means, the plastic sleeve means surrounding each of said bearings between the bearings and the turbine casing and extending longitudinally between said bearings over the turbine peripheral surface and impelling means for insulating the bearings from said casing and deflecting fluid escaping from the turbine impelling means which would normally strike the casing, means extending through the handle and communicating with the turbine from said handle into the turbine casing through the plastic sleeve means opening for supplying fluid to the turbine to rotate said turbine, means extending through the handle and communicating with the turbine from said handle into the turbine casing through the plastic sleeve means opening for exhausting fluid from said turbine, and means connected to the turbine substantially aligned with said turbine casing longitudinal axis for holding a dental burr.

'7. Fluid-driven dental handpiece construction as defined in claim 6 in which the plastic sleeve means is formed from memory plastic.

8. Fluid-driven dental handpiece construction as defined in claim 7 in which the memory plastic is a polymerized tetrafluoroethylene composition.

References Cited in the file of this patent UNITED STATES PATENTS 2,251,057 Iseman July 29, 1941