RADIO CONTROL SYSTEM FOR CAMERA

• US 3,686,672 A
• Filed: 12/12/1969
• Issued: 08/22/1972
• Est. Priority Date: 12/19/1968
• Status: Expired due to Term

• Current Assignee: Shigeru Ishizuka
• Original Assignee: Shigeru Ishizuka
• Inventors: Ishizuka, Shigeru
• Primary Examiner(s): Habecker, Thomas B.
• Assistant Examiner(s): Wannisky, William M.
• Application Number:
  US04/884,457
• Time in Patent Office: 984 Days
• Field of Search: 343/225 340/221 317/146 320/1 95/11.5A,53E,53EA,53EB
• US Class Current: 361/182
• CPC Class Codes: G03B 17/38 Releasing-devices separate from shutter integral with shutter G03B9/08

Abstract

The inventive radio system for controlling the operation of shutter of a camera comprises a transmitter for transmitting a signal of a radio frequency, a receiver for receiving said signal from said transmitter and an actuator circuit connected to an electro-magnetic plunger which in turn is mechanical coupled to a release member of the shutter assembly. The actuator circuit comprises an oscillator circuitry and a charging circuitry which are electrically connected to each other through a transformer so that electrical energy is charged in the charging circuit to a predetermined level. The charging circuitry has a switching element at the output side thereof connected to the electromagnetic plunger, which element is usually open and closed, only when there appears a signal at the output of said receiver, to thereby discharge the charged energy through said electrical plunger. The latter then actuates the release member of the shutter assembly. As an additional inventive feature, the actuator circuit may comprise means for supplying a constant current to the electro-magnetic plunger after the latter has been actuated as above mentioned. This additional means comprises a diode connected to a power source of the oscillator circuitry and to the magnetic winding of the plunger by way of said switching element.

Claims

1. A radio control system for remotely and wirelessly controlling the shutter operation of a photographic camera, comprising:

a radio frequency transmitter for producing and emitting a photographing signal of a radio frequency, a radio frequency receiver for receiving said photographing signal and producing a voltage at output thereof, a relay having an energizing coil connected to said output of said receiver and a pair of alternatively switchable contacts, one of which is closed by a movable contact actuated by an armature controlled by said relay coil when said output voltage of said receiver is applied to said coil, while the other contact is normally closed, said movable contact being connected to a direct current battery, a release actuator having a movable magnetic element adapted to be operationally coupled to a release member of the shutter of a camera and winding enclosing said movable element to electromagnetically move said element to thereby actuate said release member upon being energized, said winding having first and second terminals, said first terminal being connected to said one contact of said relay, a charging condenser having first pole connected to said second terminal of said actuator winding and second pole connected to said direct current battery by way of an oscillating switch, a step-up transformer having primary, secondary and feedback windings, a first rectifier connected between one end of said secondary winding and said first pole of said charging condenser, a second rectifier forwardly connected between said first pole of said charging condenser and said battery, and a transistor having collector, base and emitter, said collector being connected to one end of said primary winding of said step-up transformer, the other end of which is connected to said normally closed contact of said relay, said emitter being connected to said battery and coupled to one end of said feedback winding, And said base being connected to both of other ends of said secondary and feed back windings of said step-up transformer.