Patent US2441564A successfully refreshed from Google Patents.
US3579833A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Odontological instrument
Assignee: Individual
•
Filing: 1969-01-02
•
Granted: 1971-05-25
•
Expires: 1989-01-02
Abstract
Abstract An odontological instrument for introduction into and hollowing out the root channels of the teeth, comprising an angled-off longitudinal handle terminating in a head accommodating a worm and worm wheel, fixed and movable cam means, a spring acting upon the movable cam, and a tool carrying shaft which imparts to the tool a screwing movement and a rapid axial retracting movement.
Inventors
- 👤 Americo Colombo
- 👤 Ugo Ronchetti
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 17:20
CPC Classifications
A; A61; A61C; A61C1/00; A61C1/02; A61C1/04
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
305 words
An odontological instrument for hollowing out the root channels of the teeth, comprising: an angled-off longitudinal handle terminating in a head; chuck means carried by said head for mounting a tool; a drive shaft mounted in said handle; speed reducing means comprising a worm gear fixed to said drive shaft and a pinion gear rigid with said chuck means connecting said drive shaft with said chuck means for imparting rotary movement to said chuck means at a reduced speed; a fixed cam carried by said head; a ratchet cam rigid with said chuck means for cooperation with said fixed cam; and spring means acting on said ratchet cam urging it into engagement with said fixed cam whereby a predetermined plurality of revolutions of said worm gear results in a single revolution of said chuck means and alternate, axial forward and rearward movement is imparted to said chuck means at least once during each revolution of said chuck means, said cams being formed of a pair of inclined, cooperating, similar, steadily rising, annular, cam faces movable relative to each other in a circumferential direction of the chuck means for the odontological instrument and interrupted in at least one position in said circumferential direction by a surface extending axially of said chuck means, said annular cam faces beginning to rise steadily at the axially extending surface and being kept in engagement with each other during their movement relative to each other in said circumferential direction by said spring means so that said chuck means for the odontological instrument will carry out a relatively slow axial forward movement with a simultaneous limited rotary movement as long as said annular cam faces slide on each other, but will carry out a rapid axial retracting movement under the action of said spring means when said axially extending surfaces are aligned.
Claim 2
Dependent Claim
305 words
An odontological instrument for hollowing out the root channels of the teeth, comprising: an angled-off longitudinal handle terminating in a head; chuck means carried by said head for mounting a tool; a drive shaft mounted in said handle; speed reducing means comprising a worm gear fixed to said drive shaft and a pinion gear rigid with said chuck means connecting said drive shaft with said chuck means for imparting rotary movement to said chuck means at a reduced speed; a fixed cam carried by said head; a ratchet cam rigid with said chuck means for cooperation with said fixed cam; and spring means acting on said ratchet cam urging it into engagement with said fixed cam whereby a predetermined plurality of revolutions of said worm gear results in a single revolution of said chuck means and alternate, axial forward and rearward movement is imparted to said chuck means at least once during each revolution of said chuck means, said cams being formed of a pair of inclined, cooperating, similar, steadily rising, annular, cam faces movable relative to each other in a circumferential direction of the chuck means for the odontological instrument and interrupted in at least one position in said circumferential direction by a surface extending axially of said chuck means, said annular cam faces beginning to rise steadily at the axially extending surface and being kept in engagement with each other during their movement relative to each other in said circumferential direction by said spring means so that said chuck means for the odontological instrument will carry out a relatively slow axial forward movement with a simultaneous limited rotary movement as long as said annular cam faces slide on each other, but will carry out a rapid axial retracting movement under the action of said spring means when said axially extending surfaces are aligned.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-05-24 | 1974-11-23 | 1975-05-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-05-24 | 1978-11-23 | 1979-05-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-05-24 | 1982-11-23 | 1983-05-25 | $7700.00 | Window Closed / Lapsed |