Abstract: A mixed air conditioning controller is formed as a factory assembled and adjusted unit in a compact housing, with simple and direct input/output field connectors. Various temperature and humidity input devices are field connected to produce a sequenced control of the air dampers and mechanical cooling and heating devices, as well as auxiliary devices. The controller includes a primary input related to room demand, an outside air temperature input, with an interlocked control to the damper, a fan status input, a minimum air supply control and a by-pass switch having a low limit input. The logic network connecting the input/output includes pneumatic switching, pressure selecting and comparing devices of a diaphragm-controlled-orifice construction connected to function as fluidic repeaters, pressure regulating valves and pressure isolating and switching devices. The controller includes a conditioning channel and a damper channel.

Abstract: A thermal energy storage apparatus and method employs a container formed of soda lime glass and having a smooth, defect-free inner wall. The container is filled substantially with a material that can be supercooled to a temperature greater than 5.degree. F., such as ethylene carbonate, benzophenone, phenyl sulfoxide, Di-2-pyridyl ketone, phenyl ether, diphenylmethane, ethylene trithiocarbonate, diphenyl carbonate, diphenylamine, 2-benzoylpyridine, 3-benzoylpyridine, 4-benzoylpyridine, 4-methylbenzophenone, 4-bromobenzophenone, phenyl salicylate, diphenylcyclopropenone, benzyl sulfoxide, 4-methoxy-4PR-methylbenzophenone, N-benzoylpiperidine, 3,3PR,4,4PR,5 pentamethoxybenzophenone, 4,4'-Bis-(dimethylamino)-benzophenone, diphenylboron bromide, benzalphthalide, benzophenone oxime, azobenzene. A nucleating means such as a seed crystal, a cold finger or pointed member is movable into the supercoolable material. A heating element heats the supercoolable material above the melting temperature to store heat.

Abstract: A low-powered electric to fluid valve unit includes a housing having a supply port connected to a pneumatic source and an output port connected to a pneumatic operator. A disc spring is clamped about the periphery within the housing. The peripheral portion is connected by a plurality of spring arms to a sealing disc located between the inner end of the supply port and an exhaust port. The disc spring is formed of a suitable spring material which may be of a magnetic or non-magnetic material. The disc is coated with a silicone rubber sealant. The housing is closed by an electromagnetic assembly threaded into the housing and having an E-shaped iron core having a coil wound about the central leg and connected to a signal source. The central core leg is formed with an exhaust opening and aligned with the spring disc. An iron pad is provided on the backside of the spring disc and is spaced slightly from the E-shaped iron core to define a working air gap.

Abstract: A control arrangement for a pilot ignition type fuel ignition system includes a first switch device which effects energization of a pilot valve at the start of an operating cycle to supply fuel to a pilot outlet for ignition to provide a pilot flame. The first switch device is enabled by a control circuit which in turn is enabled over a path provided by a second switch device. The second switch device is enabled by a flame sensing circuit when a pilot flame is established and operates to effect energization of a main valve and to interrupt the enabling path for the control circuit, and a further flame sensing circuit maintains the first switch device, and thus the pilot valve, operated following operation of the second switch device.

Abstract: A multiple bladed air damper unit for heating, ventilating and air conditioning systems includes separate and individual end edge seal elements sealing off the end edges to the frame in the closed position. The seal elements are mounted in end-to-end relation and define an essential continuous flat sealing surface in opposed, abutting alignment with the individual flat planar end edges of the blades. Each seal element is a thin, spring-like resilient metal plate of a length essentially identical to that of the end edge of the blades. The metal seal element has a crowned cross-section defining a central, generally flat seal portion integrally interconnected by inclined walls to mounting edges. A central opening is provided for the blade pivot shaft. The element is compressed between the end of an aligned blade and the damper frame to establish a resilient, sliding engagement between the blade and flat seal portion.

Abstract: A control system for use with gas-fired appliance installations, such as a furnace, includes a switch responsive to normal draft levels in the vent stack. At the start of a heating cycle, and in the absence of draft, the switch permits a pre-draft enabling circuit to tentatively enable the furnace controller for a predetermined time. The controller opens a stack damper plate and actuates the ignition system and gas valves of the furnace. If draft is not established within the predetermined time, the pre-draft enabling circuit times out and the gas is shut off. If normal draft is sensed within the predetermined time, the draft responsive switch permits the furnace controller to be operated as long as the thermostat calls for heat. If, for any reason, draft subsequently stops, the control system re-cycles itself; and if draft is not re-established before the pre-draft enabling circuit times out, the system deactivates the furnace controller.

Abstract: A fluid pneumatic circuit board includes a base plate and a flat cover plate molded of a suitable plastic such as polysulfone. The plates are chemically bonded with a thermal adhesive such as a refrigerated solid sheet of epoxy. The base plate has a planar surface within which the fluid circuit passageways, as well as structural board and component supports are integrally molded. The cover plate has individual sealing ribs formed to encircle each of the passageways. The epoxy sheet is shaped to cover the passageways, and with openings aligned with the exhaust openings in the cover plate. The plates, with the adhesive sheet therebetween, is clamped together and heated in an oven to soften the adhesive. The sealing rib has inclined sidewalls and an outer flat sealing wall, with an included angle of 60.degree. and a tip width equal to the sheet thickness and a height equal 21/2 times the sheet thickness. Moisture and/or gas in the softened plastic escape from under the tip and prevent formation of bubbles.

Abstract: A vacuum operated sewerage system includes a static pressure sensor establishing a trigger signal at selected first level in a standpipe. The sensor is connected upstream of a discharge control valve and actuates a timer at the selected sensed pressure. The timer is connected to actuate the discharge control valve after a suitable time delay to prevent transient signal actuation, and establish flow for a predetermined period. An air admission valve is connected in series with the sensor to the timer to actuate the timer if the system vacuum drops below a selected level in the same manner as an increased hydrostatic pressure. The sensor can be eliminated for separate air admission control directly in response to the vacuum condition of the line.

Abstract: A temperature sensitive thick film resistor unit for use in detecting and control systems is formed employing thick film plating technology. A final sized negative is formed from enlarged artwork and transferred to a photosensitive emulsion supported on a stainless steel screen to form a printing stencil. A fritted molecular bonding nickel paste including finely divided vitreous and nickel particles in a solvent carrier is screen printed onto an alumina substrate by a pressure printer in which the paste is forced through the screen to control the thickness of the deposited nickel paste. The deposited nickel is allowed to settle and partially heated to remove gases and organic solvents. A highly conductive film is overlaid on tab connecting ends and the unit is fired to intimately attach the nickel paste to the substrate by the formation of a chemical bond.

Abstract: A fuel ignition control system including a control arrangement for operating pilot and main valves of the system the pilot valve being operated to permit a pilot flame to be established, and the main valve being operated by a pilot flame sensing circuit which includes a controlled switching device enabled in response to the charging of a capacitor to a given value to effect the operation of the main valve, the charging of the capacitor being controlled by a further controlled switching device which supplies AC current to the capacitor in the absence of a pilot flame, preventing the capacitor from charging to the given value, and which supplies DC current to the capacitor when a pilot flame is established, permitting the capacitor to charge to the given value.

Abstract: A control arrangement for a direct ignition type fuel ignition system including a timing circuit having a timing capacitor which charges in response to application of power to the system defining a trial for ignition interval during which a controlled switching device is enabled to operate a flame relay to energize a fuel valve to supply fuel to a burner for ignition by sparks provided by a spark generator, the controlled switching device being disabled, deenergizing the flame relay when the timing capacitor becomes fully charged before the fuel is ignited, and the controlled switching device being maintained enabled through the action of a flame sensing circuit which is coupled to the timing circuit only when a flame is established.

Abstract: A loop communication system includes a loop controller originating and terminating parallel output multiple bit message frames over a pair of trunks to remote stations, each of which includes a multiplexing connection means to the incoming trunk segments, with means to selectively and operably connect one of the incoming trunk segments to a frame processor. A pair of transmitters are also provided at the interface means and actuated to synchronously and correspondingly retransmit the process signal over the two outgoing trunk lines or segments. A logic circuit directly transmits the signal from one receiver and blocks the other until the first fails. The message is processed and retransmitted by a pair of transmitters over the two outgoing trunk segments. Suitable indicators coupled into the logic circuit signal the failure. A contact status circuit initiates transmission of the failure location via message frames to the controller.

Abstract: A linear variable differential transformer includes a primary winding and two secondary windings in spaced stacked relation on a core unit. The core unit includes similar cup-shaped pot cores mounted in opposed opening relationship and having abutting cylindrical outer walls and spaced cylindrical inner walls define an annular chamber within which the windings are located. A core axis located within the central air gap between the inner walls and terminates in close relation to the windings. A movable stem couples the core to a pressure diaphragm transducer to locate the core in accordance with pressure.

Abstract: An element for sensing the presence of nitrogen dioxide gas in the environment. The element comprises a film of a pyrolyzed polyaromatic polymer having semi-conductive properties which is mounted on an electrically non-conductive base. Electrical leads are attached at spaced locations to the film and are connected in an electrical circuit with a signalling or control mechanism. The presence of nitrogen dioxide gas will cause a change in the electrical characteristics of the film to thereby activate the mechanism. A heating element can be associated with the base to insure constant temperature and humidity conditions.

Abstract: A fuel ignition system of the pilot ignition type including a control circuit for operating pilot and main valves of a redundant valve assembly, the control circuit having control relays which provide an interlock on start-up to prevent the energization of the valves under certain failure conditions, the control circuit including a flame sensing circuit which is operable to prevent start-up of the system when a flame is provided as the result of a leak condition for the pilot valve, and to terminate an ignition cycle causing complete shut off of fuel whenever a flame is provided as the result of a leak condition for the main valve.

Abstract: A control circuit for a fuel ignition system of the direct ignition type for providing an interlock on start-up to prevent the energization of a fuel supply valve of the system under certain failure conditions includes an interlock relay which is energized, after a predetermined delay, over normally closed contacts of a flame relay to control a timing network to cause a flame sensing circuit to enable the flame relay to energize the valve during a trial for ignition interval defined by the timing network, the flame sensing circuit maintaining the flame relay, and thus the valve, energized when a flame is provided during the trial for ignition interval, the energization of the valve and the interlock relay being prevented if the normally closed contacts of the flame relay are open on start-up, and the delayed operation of the interlock relay preventing lockout of the system following momentary loss of power.

Abstract: A self-checking fuel ignition system of the pilot ignition type including a sampling flame sensor which effects periodic testing of the operability of a spark generating circuit to provide ignition sparks, and an energizing circuit which operates independently of the spark generating circuit but under the control of the flame sensor, to control the operation of fuel valves of the system and to effect the shut down of the system for loss of flame or ignition spark.

Abstract: A fluid pneumatic circuit board includes a base plate and a flat cover plate molded of a suitable plastic such as polysulfone. The plates are chemically bonded with a thermal adhesive such as a refrigerated solid sheet of epoxy. The base plate has a planar surface within which the fluid circuit passageways, as well as structural board and component supports are integrally molded. The cover plate has individual sealing ribs formed to encircle each of the passageways. The epoxy sheet is shaped to cover the passageways, and with openings aligned with the exhaust openings in the cover plate. The plates, with the adhesive sheet therebetween, is clamped together and heated in an oven to soften the adhesive. The sealing rib has inclined sidewalls and an outer flat sealing wall, with an included angle of 60.degree. and a tip width equal to the sheet thickness and a height equal 21/2 times the sheet thickness. Moisture and/or gas in the softened plastic escape from under the tip and prevent formation of bubbles.

Abstract: A control arrangement for a heating system including a furnace having a fuel-fired burner apparatus and a vent stack with a motor driven damper plate for opening and closing the stack, includes an interlock switch which provides a safety interlock between fuel supply valves of the system and first and second limit switches which control the energization of a drive motor for the damper plate and effect energization of the fuel supply valves of the system, permitting the fuel valves to operate only when the damper plate is in the open position and preventing energization of the fuel valves in the event of a malfunction of either of the limit switches. The interlock switch also permits recycling of the system in the event of a momentary power interruption. The control arrangement may include a stack mounted heat sensor switch which interrupts the energizing path for the fuel supply valves in the absence of heat from the main burner within a predetermined interval of time.

Abstract: A gas valve having first and second redundant valve members, disposed in a passageway between an inlet and an outlet of the valve which are individually operable to open and close respective inlet and outlet valve ports, and a pressure regulating apparatus interposed between the inlet and outlet valve ports operable to supply gas to the outlet valve port initially at a pressure lower than the inlet pressure when the first and second valve members are operated to open respective valve ports, and to gradually increase the pressure of the gas supplied to the outlet valve port until the outlet pressure equals a value intermediate the inlet pressure and the initial outlet pressure, as established by a pressure regulator spring of the pressure regulating apparatus. The gas valve is disclosed with reference to an application in a fuel ignition system to regulate gas flow to a combustion box to minimize ignition noise and rollout of gas flame from the combustion box.