RANDOM CYCLE LOAD SWITCH

• US 3,763,377 A
• Filed: 04/10/1972
• Issued: 10/02/1973
• Est. Priority Date: 04/10/1972
• Status: Expired due to Term

• Current Assignee: Allen H. Weston
• Original Assignee: Allen H. Weston
• Inventors: Weston, Allen H.
• Primary Examiner(s): Hohauser, Herman J.
• Application Number:
  US05/242,573
• Time in Patent Office: 540 Days
• Field of Search: 307/11,17,140,149,252B
• US Class Current: 307/140
• CPC Class Codes: H03K 17/723 using transformer coupling

Abstract

Current to a primary load is sensed and utilized in order to simultaneously complete a circuit which includes a secondary load and a triac. A current transformer has a primary winding in series with the primary load and a secondary winding coupled to the cathode and gate electrodes of the triac, so that a current to the primary load will cause a gate current sufficient to switch the triac from a non-conducting state to a conducting state.

Claims

1. Apparatus for supplying current to a secondary load simultaneously with current flow from a voltage source to a primary load, comprising a secondary load connected to the voltage source and a triac, a current transformer having a winding connected to the voltage source and the primary load and having a winding with one end connected to the cathode of said triac and its other end connected through a resistor to the gate of said triac, whereby current flow from the voltage source to the primary load will initiate a flow of current to said gate electrode and cuase said triac to become conducting, thereby completing the circuit which includes the voltage source, the triac, and the secondary load.

2. Apparatus for operating a source of illumination in conjunction with the operation of an electrical appliance which is connected to a voltage source, comprising a source of illumination electrically connected in a circuit with a voltage source and a triac having anode, cathode, and gate electrodes, a current transformer having a primary winding connected to the voltage source and the appliance, said transformer having a secondary winding having one end connected to said cathode and its other end connected through a resistor to said gate electrode, whereby current to the appliance causes a gate current sufficient to cause the triac to switch to a conducTing state to complete the electrical circuit which includes said source of illumination.

3. Apparatus for turning a lamp on and off simultaneously with the random on and off operation of a refrigerator motor which is connected to a voltage source, comprising a lamp located externally of the refrigerator, a triac having anode, cathode and gate electrodes, said lamp being connected to said voltage source and to said anode, a current transformer having a primary winding connected to the voltage source and the refrigerator motor, said transformer having a secondary winding having one end connected to said cathode and its other end connected through a resistor to said gate electrode, whereby said triac is in a non-conducting state when the refrigerator motor is off and is in a conducting state when the refrigerator motor is on.