US3595221A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Endoscopic having illumination supply unit
Assignee: Smiths Group PLC
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Filing: 1969-03-04
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Granted: 1971-07-27
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Expires: 1989-03-04
Abstract
Abstract The disclosure relates to endoscopic instruments. The instrument is supplied through a circuit including a stepdown output transformer. A secondary winding of the transformer is connected with a light source of the endoscope. A push-pull oscillator circuit is connected with the primary winding of the output holdup oscillator circuit is connected to a current source and is arranged to supply current to the primary at a frequency of not less than 15 kHz.
Inventors
- 👤 John Harold Blackett
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 07:03
CPC Classifications
A; A61; A61B; A61B1/00; A61B1/00002; A61B1/00004; A61B1/00006; A61B1/06; A61B1/0661; A61B1/0676
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
61 words
An endoscope with a light source; a stepdown output transformer having primary and secondary windings, the secondary being connected with the light source; and a push-pull oscillator circuit of a frequency not less than 15 kHz. which is connected with the primary of the transformer and also has means by which it can be connected to a source of electric current.
Claim 2
Dependent Claim
61 words
An endoscope with a light source; a stepdown output transformer having primary and secondary windings, the secondary being connected with the light source; and a push-pull oscillator circuit of a frequency not less than 15 kHz. which is connected with the primary of the transformer and also has means by which it can be connected to a source of electric current.
Claim 3
Dependent Claim
55 words
An endoscope as claimed in claim 1 wherein the oscillator circuit is connected with a supply circuit including a primary adapted to be connected to an electric mains and a secondary connected in the supply circuit, a full wave rectifier and a means for controlling the voltage of the current supplied to the oscillator circuit.
Claim 4
Dependent Claim
45 words
An endoscope as claimed in claim 1 wherein the oscillator circuit is connected with a supply circuit energized by an electric battery, the said circuit including a switch connected in series with the battery and a capacitor and a pilot light, connected across the circuit.
Claim 5
Dependent Claim
19 words
An endoscope as claimed in claim 1 wherein the oscillator circuit includes a pair of low power silicon transistors.
Claim 6
Dependent Claim
23 words
An endoscope as claimed in claim 4 having means for switching off the oscillator when there is a short circuit in the endoscope.
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) | 1974-07-26 | 1975-01-25 | 1975-07-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-26 | 1979-01-25 | 1979-07-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-26 | 1983-01-25 | 1983-07-27 | $7700.00 | Window Closed / Lapsed |