Ronald L Rose

US Patent:

39783529, Aug 31, 1976

Filed:

Dec 9, 1974

Appl. No.:

5/531208

Inventors:

Ronald N. Rose - Minneapolis MN

International Classification:

H03K 1700

US Classification:

307308

Abstract:

A circuit for maintaining any medium between two predetermined limits, as for example, the water level in a sump. Current to drive the sump pump is gated through a programmable unijunction transistor which transistor is turned on by a signal from an upper limit probe in the sump which is activated by the water level reaching the probe position. When the transistor turns on it activates another portion of the circuit also utilizing programmable unijunction transistors which operates to turn off the first transistor in response to a signal from a lower limit probe positioned in the sump at a lower level. Silicon controlled rectifiers or transistor regenerative switch circuits may be substituted for the unijunction transistors.

US Patent:

40652270, Dec 27, 1977

Filed:

Aug 17, 1976

Appl. No.:

5/715190

Inventors:

Ronald N. Rose - Minneapolis MN

International Classification:

F04B 4900
G02B 2700
H03K 342

US Classification:

417 45

Abstract:

A circuit to maintain the water level between low and high predetermined limits in a sump in which the signal from an upper limit probe operates a first lamp which illuminates a photo resistor controlling the gate of a triac. The triac turns on and enables a second lamp connected to a lower limit probe which illuminates the photo resistor and holds the triac on until the fluid level drops below the lower limit probe.