Robert Bruce MacaskillNorth Olmsted, OH

4024412, May 17, 1977

Feb 7, 1975

5/547902

Robert Bruce MacAskill - Rockford IL

The Scott & Fetzer Company (France Division) - Westlake OH

H01H 3700

307117

A primary side of a burner control circuit includes a triac switch for applying a line voltage to a burner motor and an igniter in response to a signal from a first optical coupler, and a circuit breaker responsive to a second optical coupler for disconnecting the primary from the line voltage. A low voltage or secondary side of the control circuit, which is responsive to a thermostat, contains a light sensitive element for detecting a flame at the burner and the light sources for both optical couplers and, as such, is effective to control both the triac and the circuit breaker. The secondary also contains an electrical timing circuit for causing the triac to shut the motor and igniter off when, a predetermined time after a call for heat by the thermostat has elapsed, a flame has not been detected in the furnace. In addition, the burner control circuit includes a fail-safe capability for opening the circuit breaker if the triac has failed into a permanently closed condition and there is no call for heat or the burner flame has gone out; thereby preventing the system from overheating or filling with fuel.

3938939, Feb 17, 1976

Feb 12, 1975

5/549409

Robert Bruce MacAskill - Rockford IL
Charles Norvin Porter - Rockford IL

Sundstrand Corporation - Rockford IL

F23N 508

431 79

The primary side of the burner control circuit, which has as its primary function the application of a line voltage to the burner motor and igniter, includes: a triac switch for applying the line voltage to the burner motor and igniter; in response to a first optical coupler; a circuit breaker switch for disconnecting the primary from the line voltage; and a light source for a second optical coupler. The secondary side of the burner control circuit, which is responsive to a thermostat, includes: a light sensitive element for detecting a flame at the burner; a light source for the first optical coupler; and a current responsive element which in combination with the circuit breaking switch in the primary functions as a circuit breaker. The first optical coupler responds to the thermostat to cause the triac switch to connect the motor and igniter to the line voltage and, if a flame is not sensed within a predetermined time by the light sensitive element, the circuit breaker will disconnect the motor from the line voltage. In addition, the second optical coupler serves as a safety device to disconnect the motor from the line voltage by means of the circuit breaker whenever the triac is in a shorted condition and the thermostat is not calling for heat.

4222089, Sep 9, 1980

Nov 10, 1977

5/850428

Robert B. MacAskill - Bay Village OH
Archie R. Cornell - Avon Lake OH

The Scott & Fetzer Company - Westlake OH

F23Q 300

361263

The high voltage transformer for the ignition system of an oil burner and the control system for the oil burner are packaged together in a single housing. The duty cycle of the transformer is discontinuous. The transformer core is of symmetric U-I configuration but the coil arrangement is asymmetric with a single primary coil being provided. The transformer is not potted, the core ends are free of coils, and one core end overlaps a circuit board for the control system to thereby foreshorten the overall package. Although the transformer is not potted, tight constraints against shorting of the high voltage secondary leads are maintained by provision of an insulator bushing means which is positioned in apposition to the transformer secondary coils by means of a bracket which also provides a mounting for the transformer core, the high voltage leads being drawn through the insulator bushing means and secured at terminal contacts at the lower ends of the bushing means. The entire package is hinged for movement into and out of working association with the ignition leads of an oil burner.

4682082, Jul 21, 1987

May 16, 1985

6/734546

Robert B. MacAskill - Bay Village OH
Jeffrey J. Braun - Parma OH

The Scott & Fetzer Company - Cleveland OH

H05B 4114

315219

An electronic energization circuit is provided to illuminate a gas discharge lamp that includes a transformer with a substantially rectangular hysteresis loop. A secondary winding on the transformer is connected to energize the lamp and at least one primary winding is provided on the transformer. Input voltage terminals may be DC terminals to supply an input voltage to the circuit. At least one semiconductor, such as a transistor, is connected to the input terminals and to the at least one primary winding, and a control means is provided for the semiconductor for unequal on and off conduction periods of the semiconductor. These unequal periods provide the conditions which eliminate the striations (bubbles) or dark spots in the gas plasma of the lamp, usually associated with high frequency energization. When two semiconductors are used in a circuit, they conduct alternately in a type of square wave oscillator circuit and the duty cycle of the two transistors is different so that the striations in the illumination of the lamp are eliminated. The foregoing abstract is merely a resume of one general application, is not a complete discussion of all principles of operation or applications, and is not to be construed as a limitation on the scope of the claimed subject matter.