US3902248A

US3902248A - Dental handpiece

Info

Publication number: US3902248A
Application number: US371845A
Authority: US
Inventors: Frich Bareth
Original assignee: Kaltenbach and Voigt GmbH
Current assignee: Kaltenbach and Voigt GmbH
Priority date: 1972-07-12
Filing date: 1973-06-20
Publication date: 1975-09-02
Anticipated expiration: 1992-09-02
Also published as: FR2191869B1; DE2234321B1; AT352860B; JPS5412000B2; BR7305124D0; ATA518073A; DE2234321C2; FR2191869A1; JPS50157988A

Abstract

A dental handpiece having an improved novel tool-receiving sleeve arrangement facilitating the simplified actuation of an adapter sleeve of the handpiece, including rolling or rotatable members, preferably in the shape of spheres or balls, which effectively provide roller or ball bearing supports for the adapter sleeve so as to facilitate the threading movement of the adapter sleeve in an extraordinarily simple sequence.

Description

United States Patent [191 Bareth [4 1 Sept. 2, 1975 DENTAL HANDPIECE [75] Inventor: Frich Bareth, Ummendorf, Germany [73] Assignee: Kaltenbach & Voigt, Biberach an der Riss, Germany [22] Filed: June 20, 1973 [21] Appl. N0.: 371,845

[30] Foreign Application Priority Data July 12, 1972 Germany 2234321 [52] US. Cl 32/26; 279/46 [51] Int. Cl. A61c 1/08 [58] Field of Search 32/26; 279/46, 51

[56] References Cited UNITED STATES PATENTS 2,876,015 3/1959 Stever et al 32/26 X 3,400,459 9/1968 Stemler 32/26 3,475,817 11/1969 Loge 32/26 3,496,638 2/1970 Staunt.... 32/26 3,518,765 7/1970 Hayashi 32/26 3,530,586 9/1970 Weickenannt... 32/26 3,619,904 11/1971 Lundgren 32/26 3,631,597 1/1972 Lieb 32/26 3,775,851 12/1973 Flatland 32/26 Primary Examiner-Louis G. Mancene Assistant Examiner-J. Q. Lever Attorney, Agent, or Firm-Haseltine, Lake & Waters [5 7] ABSTRACT A dental handpiece having an improved novel toolr'eceiving sleeve arrangement facilitating the simplified actuation of an adapter sleeve of the handpiece, including rolling or rotatable members, preferably in the shape of spheres or balls, which effectively provide roller or ball bearing supports for the adapter sleeve so as to facilitate the threading movement of the adapter sleeve in an extraordinarily simple sequence.

3 Claims, 1 Drawing Figure DENTAL HANDPIECE FIELD OF THE INVENTION The present invention relates to a dental handpiece and, more particularly. to a novel arrangement enabling the simplified actuation of a tightening or adapter sleeve for the handpiece.

DISCUSSION OF THE PRIOR ART Dental handpieces of this type are known, for example, from German Laid-open patent application No. 1,816,270, in which an adapter sleeve operatively engages a slide lock so as to move the latter toward the tool-supporting end of the handpiece in a direction extending parallel to the axis of the handpiece. Thereby, the slide lock presses against an abutment which is contacted by a spring retaining the adapter sleeve in alocking position, so as to remove the spring effect, permitting the adapter sleeve to move from its locking position, and facilitate withdrawal of the tool. In order to prevent the spring from reversely screwing the adapter sleeve, it is necessary to utilize a self-locking thread for the adapter sleeve. However, self-locking threads have only a relatively small pitch and, moreover, must be extremely precisely manufactured with close fits and tolerances. This has the result that the thread may be actuated only with extreme difficulty.

Accordingly, it is a primary object of the present invention to provide a dental handpiece having an improved and novel arrangement facilitating the simplifled actuation of the adapter sleeve of the handpiece.

In order to achieve the foregoing object the present invention, in an inventive manner, provides rolling or rotatable members, preferably in the shape of spheres or balls, which effectively provide roller or ball bearing supports for the adapter sleeve so as to facilitate the threading movement of the adapter sleeve in an extraordinarily simple sequence. This is particularly advantageous since, in this manner, the spring force which operates in opposition to the threading process movement through the use of the above-mentioned balls or rollers, does not restrictively occur to any significant extent.

In order to nevertheless provide with assurance the only weakly or practically non-detected appearing selflocking, so as to prevent any undesired unthreading of the adapter sleeve, the handpiece may be formed with a releasable locking arrangement which is actuatable in the operative end positions of the adapter sleeve. This locking arrangement may advantageously be formed by a spring-loaded catch or lock, whereby upon unthreading from the end-threaded position only the force of the locking spring need be overcome. Furthermore, in order to assure that the rolling members are secured against falling out of grooves in which they are located, suitable limiting or arresting stops may be provided adjacent the passageways defined by the ball-receiving grooves.

BRIEF DESCRIPTION OF THE DRAWING Reference may now be had to a preferred exemplary embodiment of the invention taken in conjunction with the accompanying drawing, in which the single FIG- URE illustrates in a longitudinal section a dental handpiece having an adapter sleeve shown in its locking position.

DETAILED DESCRIPTION Referring now in detail to the drawing, a forward end sleeve of the handpiece is designated by the reference numeral 1. A'suitable gripping sleeve 2 is threaded into sleeve 1, with the threaded portion between sleeves l and 2 being designated by reference numeral 3.

A spindle sleeve 4 is located within sleeve 1, being supported at its right-hand end as shown in the drawing within sleeve 1 by means ofa ball bearing 5. A further support for the spindle sleeve 4 is designated by reference numeral 6. At the right-hand end of the spindle sleeve 4 there is provided a suitable connector or follower 7 for attachment thereto of a drive shaft and motive means (not shown).

The spindle sleeve 4 is encompassed by a compression spring 8 which contacts an external ring-shaped projection 9 formed on the spindle sleeve comprising an abutment support and, which by means of a pressure member 10 and a transversely extending pin 11, operates against an adapter sleeve 12 so as to bias the latter, as may be ascertained from the hereinhelow detailed description, into its locking position.

A dental tool 13 is inserted in the adapter sleeve I2. In the locking position, as illustrated in the drawing, the locking sleeve 12 lies with its outer conically-shaped tool-receiving end 15 of the spindle sleeve 4, which is located in an axially fixed position within the handpiece or, in effect, in the sleeve 1.

For releasing the pressure of spring 8, an external adapter sleeve 16 is mounted on the handpiece so as to be rotatable with respect to an inner sleeve I7 which is rigidly fastened to the handpiece. The inner wall of the adapter sleeve 16 and the outer wall of the inner sleeve 17 are respectively provided with thread-like

annular grooves

18 and 19, in which threading-engaging means is formed by means of spheres or balls 20 extending into the

grooves

18 and 19. A countersunk screw 21 extends outwardly of winding sleeve 16, having its shank portion located within a cooperative screw hole formed in a transmission sleeve 22, which in an unlocked position. is in an axial loaded engagement with the pressure member 10, and is rotatable and axially displaceable together with sleeve 16.

For maintenance of the locking position of the sleeve 16 there is provided a releasable locking arrangement. To this effect, the transmission sleeve 22 includes in its outer wall a recessed portion 23, in which is located a locking ball 24. The locking ball rests within the re cessed portion-23 under the operative effect ofa spring 25 which may be, for example, a leaf spring. Upon the outward screwing or rotation of the adapter sleeve from its locking position, the force of spring 25 is traversed, and the ball 24 moves out of the recessed portion 23 and rolls about the circumference of the transmission sleeve 22. A reversely directed movement of ball 24 until engagement thereof in the recessed portion 23 occurs upon inward screwing into the locking position. I

Upon the outward screwing of the sleeve 16 from the illustrated locking position thereof, the countersunk screw 21 together with the transmission sleeve 22 moves toward the left, whereby the last-mentioned sleeve exerts an operative force on the pressure member 10, and the latter through the transversely extending pin 11 operates against the sleeve 12, and the latter is moved toward the left out of the spindle sleeve 4.

This causes, as may be ascertained, the force of the spring 8 to be released, so that in the outwardly pressed position of the sleeve 12, the tool gripping tongues thereof are opened so as to permit withdrawal therefrom of the tool 13. In an analogous manner, upon the rotation of the sleeve 16 in the reverse direction. this will then form a locking sequence. In order to assure that the rotatable members 20, which are formed as balls, are secured against dropping out, at both ends of the passageways formed by the

grooves

18 and 19, there are located suitable stopping elements 26 in the shape of bolts, which are secured to the inner sleeve 17.

While there has been shown what is considered to be the preferred embodiment of the invention, it will be obvious that modifications may be made which come within the scope of the disclosure of the specification.

What is claimed is:

l. A dental handpiece including a rotatable locking sleeve adapted to detachably support a dental tool; resilient spring means for biasing said locking sleeve into a locking position; a spindle sleeve within said dental handpiece mounted in an axially fixed position with respect to said handpiece, said locking sleeve having a conically-shaped tool-receiving outer end, said spindle sleeve having a correspondingly conically-shaped inner end at the tool-receiving end of said handpiece contacted by said conically-shaped end of said locking sleeve in the locking position; an outer screwing-sleeve on said handpiece adapted to be actuated for releasing the spring pressure on said locking sleeve, the improvement comprising; an inner sleeve fastened rigidly to said handpiece; screw-like annular grooves formed in respectively the inner peripheral surface of said screwing-sleeve and the outer peripheral surface of said inner sleeve; said grooves being in axial alignment; and rotatable means positioned in said grooves so as to form screw-like interengaging means between said screwingsleeve and said inner sleeve, said rotatable means comprising ball bearing rotatably supported in said grooves, said screwing-sleeve being actuatable between toolunlocking and tool-locking operative end positions; and comprising releasable lock means for locking said screwing-sleeve in at least one of said operative end po sitions.

2. A dental handpiece including a rotatable locking sleeve adapted to detachably support a dental tool; resilient spring means for biasing said locking sleeve into a locking position; a spindle sleeve within said dental handpiece mounted in an axially fixed position with respect to said handpiece, said locking sleeve having a comically-shaped tool-receiving outer end, said spindle sleeve having a correspondingly conicallyshaped inner end at the tool-receiving end of said handpiece contacted by said conically-shaped end of said locking sleeve in the locking position; an outer screwing-sleeve on said handpiece adapted to be actuated for releasing the spring pressure on said locking sleeve, the improvement comprising; an inner sleeve fastened rigidly to said handpiece; screw-like annular grooves formed in respectively the inner peripheral surface of said screwing-sleeve and the outer peripheral surface of said inner sleeve; said grooves being in axial alignment; and rotatable means positioned in said grooves so as to form screw-like interengaging means between said screwingsleeve and said inner sleeve, said rotatable means comprising ball bearing rotatably supported in said grooves, said screwing-sleeve being actuatable between toolunlocking and tool-locking operative end positions; releasable lock means for locking said screwing-sleeve in at least one of said operative end positions, said releasable lock means comprising an auxiliary sleeve having a recessed portion in its outer wall; a locking ball in said recessed portion; and spring means for holding said locking ball in said recessed portion.

3. A dental handpiece including a rotatable locking sleeve adapted to detachably support a dental tool; resilient spring means for biasing said locking sleeve into a locking position; a spindle sleeve within said dental handpiece mounted in an axially fixed position with respect to said handpiece, said locking sleeve having a conically-shaped tool-receiving outer end, said spindle sleeve having a correspondingly conically-shaped inner end at the tool-receiving end of said handpiece contacted by said conically-shaped end of said locking sleeve in the locking position; an outer screwing-sleeve on said handpiece adapted to be actuated for releasing the spring pressure on said locking sleeve, the improvement comprising; an inner sleeve fastened rigidly to said handpiece; screw-like annular grooves formed in respectively the inner peripheral surface of said screwing-sleeve and the outer peripheral surface of said inner sleeve; said grooves being in axial alignment; and rotatable means positioned in said grooves so as to form screw-like interengaging means between said screwingsleeve and said inner sleeve, said rotatable means comprising ball bearing rotatably supported in said grooves, said screwing-sleeve being actuatable between toolunlocking and tool-locking operative end positions; re-

leasable lock means for locking said screwing-sleeve in at least one of said operative end positions; and stop means mounted at the axial ends of passageways defined by said grooves so as to prevent egress of said ro-

Claims

1. A dental handpiece including a rotatable locking sleeve adapted to detachably support a dental tool; resilient spring means for biasing said locking sleeve into a locking position; a spindle sleeve within said dental handpiece mounted in an axially fixed position with respect to said handpiece, said locking sleeve having a conically-shaped tool-receiving outer end, said spindle sleeve having a correspondingly conically-shaped inner end at the tool-receiving end of said handpiece contacted by said conically-shaped end of said locking sleeve in the locking position; an outer screwing-sleeve on said handpiece adapted to be actuated for releasing the spring pressure on said locking sleeve, the improvement comprising; an inner sleeve fastened rigidly to said handpiece; screw-like annular grooves formed in respectively the inner peripheral surface of said screwing-sleeve and the outer peripheral surface of said inner sleeve; said grooves being in axial alignment; and rotatable means positioned in said grooves so as to form screw-like interengaging means between said screwing-sleeve and said inner sleeve, said rotatable means comprising ball bearing rotatably supported in said grooves, said screwing-sleeve being actuatable between toolunlocking and tool-locking operative end positions; and comprising releasable lock means for locking said screwing-sleeve in at least one of said operative end positions.

2. A dental handpiece including a rotatable locking sleeve adapted to detachably support a dental tool; resilient spring means for biasing said locking sleeve into a locking position; a spindle sleeve within said dental handpiece mounted in an axially fixed position with respect to said handpiece, said locking sleeve having a conically-shaped tool-receiving outer end, said spindle sleeve having a correspondingly conically-shaped inner end at the tool-receiving end of said handpiece contacted by said conically-shaped end of said locking sleeve in the locking position; an outer screwing-sleeve on said handpiece adapted to be actuated for releasing the spring pressure on said locking sleeve, the improvement comprising; an inner sleeve fastened rigidly to said handpiece; screw-like annular grooves formed in respectively the inner peripheral surface of said screwing-sleeve and the outer peripheral surface of said inner sleeve; said grooves being in axial alignment; and rotatable means positioned in said grooves so as to form screw-like interengaging means between said screwing-sleeve and said inner sleeve, said rotatable means comprising ball bearing rotatably supported in said grooves, said screwing-sleeve being actuatable between tool-unlocking and tool-locking operative end positions; releasable lock means for locking said screwing-sleeve in at least one of said operative end positions, said releasable lock means comprising an auxiliary sleeve having a recessed portion in its outer wall; a locking ball in said recessed portion; and spring means for holding said locking ball in said recessed portion.

3. A dental handpiece including a rotatable locking sleeve adapted to detachably support a dental tool; resilient spring means for biasing said locking sleeve into a locking position; a spindle sleeve within said dental handpiece mounted in an axially fixed position with respect to said handpiece, said locking sleeve having a conically-shaped tool-receiving outer end, said spindle sleeve having a correspondingly conically-shaped inner end at the tool-receiving end of said handpiece contacted by said conically-shaped end of said locking sleeve in the locking position; an outer screwing-sleeve on said handpiece adapted to be actuated for releasing the spring pressure on said locking sleeve, the improvement comprising; an inner sleeve fastened rigidly to said handpiece; screw-like annular grooves formed in respectively the inner peripheral surface of said screwing-sleeve and the outer peripheral surface of said inner sleeve; said grooves being in axial alignment; and rotatable means positioned in said grooves so as to form screw-like interengaging means between said screwing-sleeve and said inner sleeve, said rotatable means comprising ball bearing rotatably supported in said grooves, said screwing-sleeve being actuatable between tool-unlocking and tool-locking operative end positions; releasable lock means for locking said screwing-sleeve in at least one of said operative end positions; and stop means mounted at the axial ends of passageways defined by said grooves so as to prevent egress of said rotatable means from said grooves.