US4286163A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dental radiographic apparatus for photographing entire jaws
Assignee: J Morita Manufaturing Corp
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Filing: 1980-03-19
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Granted: 1981-08-25
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Expires: 2000-03-19
Abstract
Abstract The disclosure relates to a dental radiographic apparatus for photographing the entire jaws wherein the apparatus includes an X-ray generator and an X-ray film cassette holder mounted respectively at one end of a rotary arm and at the other end thereof. The apparatus electrically controls an X-ray film feed speed so as to be corresponding to and synchronous with the rotatingly travelling speed of the X-ray generator.
Inventors
- 👤 Masakazu Suzuki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-08 11:27
CPC Classifications
A; A61; A61B; A61B6/00; A61B6/50; A61B6/51; H; H02; H02P; H02P5/00; H02P5/46; H02P5/50; H02P5/51
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
183 words
A dental radiographic apparatus for photographing the entire jaws wherein the apparatus includes a horizontal rotary arm and a drive motor for rotating said horizontal rotary arm, said arm having an X-ray generator at one end thereof and having an X-ray film cassette holder for a film cassette containing an X-ray film therein at the other end thereof in such manner as to dispose an object between the generator and the cassette holder and said arm further being designed to make a tomogram of the entire jaws of said object by driving said rotary arm drive motor, said photographic apparatus being characterized in that the apparatus includes a film feed motor different from said rotary arm drive motor and adapted to feed the film in said film cassette holder, a means for converting the number of rotations of said rotary arm drive motor into an electrical signal and a film feed motor drive control circuit for variably controlling the number or rotations of said film feed motor by following and in synchronism with the number of rotations of said rotary arm drive motor.
Claim 2
Dependent Claim
183 words
A dental radiographic apparatus for photographing the entire jaws wherein the apparatus includes a horizontal rotary arm and a drive motor for rotating said horizontal rotary arm, said arm having an X-ray generator at one end thereof and having an X-ray film cassette holder for a film cassette containing an X-ray film therein at the other end thereof in such manner as to dispose an object between the generator and the cassette holder and said arm further being designed to make a tomogram of the entire jaws of said object by driving said rotary arm drive motor, said photographic apparatus being characterized in that the apparatus includes a film feed motor different from said rotary arm drive motor and adapted to feed the film in said film cassette holder, a means for converting the number of rotations of said rotary arm drive motor into an electrical signal and a film feed motor drive control circuit for variably controlling the number or rotations of said film feed motor by following and in synchronism with the number of rotations of said rotary arm drive motor.
Claim 3
Dependent Claim
32 words
An apparatus according to claim 1, wherein said film feed motor drive control circuit comprises a rectifier circuit, a DC voltage-pulse converter circuit, and a drive circuit for said film feed motor.
Claim 4
Dependent Claim
52 words
An apparatus according to claim 1 wherein said means for converting the number of rotations of said rotary arm drive motor into an electrical signal converts the number of rotations of the rotary arm drive motor into an electromotive force proportional to the number of rotations of the rotary arm drive motor.
Claim 5
Dependent Claim
16 words
An apparatus according to claim 2, wherein said rotary arm drive motor is an induction motor.
Claim 6
Dependent Claim
15 words
An apparatus according to claim 1, wherein said film feed motor is a pulse-driven motor.
Claim 7
Dependent Claim
54 words
An apparatus according to claim 2, wherein said film feed drive control circuit outputs a pulse signal having a repetitive period variable in response to an AC electromotive force generated in response to the number of rotations of said rotary arm drive motor and drives the film feed motor by means of a pulse.
Claim 8
Dependent Claim
35 words
An apparatus according to claim 2, wherein a means for converting the number of rotations of said rotary arm drive motor into an electromotive force is a tachogenerator connected to the rotary arm drive motor.
Claim 9
Independent Claim
17 words
An apparatus according to claims 3 or 4, wherein said pulse-driven motor is a two-phase pulse motor.
Claim 10
Dependent Claim
24 words
An apparatus according to claim 1, wherein said film feed motor drive control circuit is enabled to vary a transfer constant of the circuit.
Claim 11
Dependent Claim
35 words
An apparatus according to claim 9, wherein a means for varying the transfer constant of said film feed motor drive control circuit is enabled to vary said AC electromotive force by use of variable resistor.
Claim 12
Dependent Claim
67 words
An apparatus according to claim 1, wherein said film feed motor is a pulse-driven motor, said means for converting the number of rotations of said rotary arm drive motor into an electrical signal as a tachogenerator connected to the rotary arm drive motor, and said film motor drive control circuit follows and varies a repetitive period of output pulse in response to the output of said tachogenerator.
References Cited (Backward Citations)
US4039837A
Cited
US4247779A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1984-08-24 | 1985-02-23 | 1985-08-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-08-24 | 1989-02-23 | 1989-08-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-08-24 | 1993-02-23 | 1993-08-25 | $7700.00 | Window Closed / Lapsed |