Abstract: A control arrangement for igniting gaseous fuel supplied to a main burner of a fuel ignition system includes a spark producing circuit to ignite the gaseous fuel for establishing a flame at the main burner, a flame sensing circuit for detecting the presence and absence of the flame, and a switching circuit responsive to the flame sensing circuit detecting the presence of the flame for maintaining a control circuit enabled to hold the valve operated and for de-activating the spark producing circuit when the flame becomes established. In the event of a flame-out condition, the flame sensing circuit enables the switching circuit to activate the spark producing circuit to attempt to re-establish the flame.

Abstract: A proportional plus integral controller connectable in a conventional proportional control loop of a process control system is selectively operable in a proportional only mode or a proportional plus integral mode in accordance with the positioning of a mode select switch and exhibits substantially bumpless forward transfer from proportional only to proportional plus integral operating modes.

Abstract: A fuel ignition control arrangement for use in a fuel ignition system includes a control circuit responsive to a thermostatically-controlled circuit element for the fuel ignition system for causing a gaseous fuel to be supplied to burner apparatus of the system, a spark-producing circuit responsive to the thermostatically-controlled element for igniting the fuel supplied to the burner apparatus, a timing circuit responsive to the thermostatically-controlled element for de-energizing the control circuit after a predetermined timing interval, and a flame sensing circuit responsive to the ignition of the fuel supplied to the burner apparatus for maintaining the control circuit in fuel supplying condition.

Abstract: A digital start-stop multiplexing system including a sender which sequentially scans a plurality of monitoring points and generates a train of digital pulses coded to represent information provided at the monitoring points for transmission over a transmission line to a receiver which is responsive to the digital pulses to automatically synchronize itself with the sender, store the data pulses and provide indications of conditions indicated at the monitoring points. The receiver also monitors the transmission line and detects and displays open or short circuit conditions of the transmission line. Coded pulses may also be transmitted from the receiver location to the remote sender over the same transmission line during stop portions of the primary signal.

Abstract: An anti-reset windup proportional plus integral controller connectable in a proportional control loop of a process control system includes a proportional amplifier circuit and an integrating amplifier circuit responsive to a command signal to provide proportional and integral signals, respectively, which are summed by a summing amplifier to provide a modified command signal having a proportional and an integral component. A signal comparator means compares the modified command with a pair of reference signals which define an output range for said summing amplifier and disables the integrating amplifier circuit, permitting the integrating amplifier circuit to unwind whenever the modified command signal is not within the output range.

Abstract: A diaphragm compressor includes a cylindrical piston and an annular diaphragm member with a central hub secured by a grommet within an annular recess in the piston face. The outer peripheral edge of the diaphragm is affixed between a clamp ring and a valve plate which has a central recess to form a compression chamber. The diaphragm has a convolution which opens toward the compression chamber. The valve plate has a projection complementing and mating with the convolution. A plurality of circumferentially spaced and radial intake ports lead to an annular piston intake opening inwardly of the diaphragm. A flexible, tee-shaped valve member includes a stem locked within the piston with a planar sealing disc having an outer bead abutting the inner piston face and overlying the intake opening. The stem may pass through a central opening with an outer stem enlargement creating a resilient clamping of the valve member to a holding portion of the piston.

Abstract: A press control includes a pair of pushbuttons each operating a pneumatic pump means to form a pair of signal pulses and an integrated valve to form a pair of binary logic pressure signals. A press position sensor provides a binary pressure signal related to the press position. The pushbutton and sensor signals are connected to fluidic logic gate means to compare and detect the actuation of the pushbuttons as well as the status of such pushbuttons and the press cycle. The logic output is connected by a plurality of logic gates to actuate a flip-flop output unit to generate an extend output or a retract output. The flip-flop output unit has an input connected to a latch input control to provide automatic reset to the retract output if release of the button signal sources occurs during a hazardous portion of the extend cycle. Once the non-hazardous portion of the extend cycle is reached, the latch is complete for the terminal portion of the extend cycle.

Abstract: A heating system has means for directing heat only to a portion of a medium for storing heat which portion is at a temperature below that to which heating means then heats the medium. The system then functions to store heat in the medium during periods of less-than-maximum heating of the medium without degrading the temperature of a higher-temperature portion of the medium. The system has particular utility with a solar heat collector from which the available heat varies with the intensity of the solar energy. Heat is then collected in the portion of the medium during periods of marginal solar energy intensity without degrading the higher temperature of another portion of the medium heated to a higher temperature during a prior period of greater solar energy intensity. In a specific embodiment the system has three compartments for separating a fluid heat-storing medium into portions, a pump supplying the fluid to a solar heat collector, and a pump supplying the fluid to a heat exchanger for heating a house.