ENDOSCOPIC HAVING ILLUMINATION SUPPLY UNIT

• US 3,595,221 A
• Filed: 03/04/1969
• Issued: 07/27/1971
• Est. Priority Date: 03/04/1969
• Status: Expired due to Term

• Current Assignee: Smiths Industries Public Limited Company
• Original Assignee: Blackett John Harold
• Inventors: BLACKETT JOHN HAROLD
• Application Number:
  US04/804,075
• Time in Patent Office: 875 Days
• US Class Current: 600/179
• CPC Class Codes: A61B 1/00006 of control signals
• CPC Class Codes: A61B 1/0676 at distal tip of an endoscope

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.

Claims

1. 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.

2. 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.

3. 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.

4. An endoscope as claimed in claim 1 wherein the oscillator circuit includes a pair of low power silicon transistors.

5. An endoscope as claimed in claim 4 having means for switching off the oscillator when there is a short circuit in the endoscope.