Abstract: A boiler includes a high intensity combustor mounted in a shell that defines the boiler housing. A coil bank is mounted in the boiler and spaced from the combustor. A fire pot is positioned in the combustor and defines a combustion chamber with a combustion throat at one end and a choke at a second end between the combustion chamber and the coil bank. The choke is formed of refractory material and includes uniformly distributed steel fibers that conduct heat across the choke from the hot side adjacent the combustion chamber to the cooler side adjacent the coil bank. The steel fibers substantially reduce the thermal gradient in the choke and improve boiler efficiency.

Abstract: A pressure relief valve includes a housing defining an internal valve chamber. A valve seat is positioned within the chamber, and a valve pallet is reciprocally mounted within the chamber to engage the seat in a valve closed mode. A spring is mounted within the housing to bias the valve pallet into engagement with the valve seat. A spring retainer is threaded through an aperture in the housing and extends into the valve chamber. The spring is located within the retainer. A desired set pressure to be imposed upon the valve pallet is provided by threading the retainer relative to the housing thereby compressing the spring. To lock the retainer relative to the housing, an annular lock member is threaded onto the outside of the retainer. Once the desired set pressure is attained, the lock member is threaded on the retainer until it abuts the housing. The lock member includes first and second ends spaced apart to define a gap.

Abstract: A door operator for opening and closing doors on transit vehicles and the like includes an actuator (50) secured to the transit vehicle (10). The actuator houses a worm drive and a reciprocating air cylinder (52) for imparting rectilinear motion to the worm drive. A door shaft (18) is coupled to a door (14) and mechanically coupled to the worm drive such that rectilinear motion of the system is transmitted by the worm drive into rotary motion to the drive shaft to open and close the door. A cam (90) is secured to the vehicle and adjacent to a cam follower (108) that is secured to the door shaft. The cam follower engages the cam during approximately the initial 80% motion during closing of the door and approximately the final 80% of the door opening. A recycling switch (200) for the door may be mounted in the vehicle adjacent to the cam in a position to be engaged upon engagement of the door with an object to recycle the door.

Abstract: A door control system, particularly suited for multiple door rapid transit vehicles wherein car operating parameters including car speed sensing (5), traction propulsion sensing (7), and other indications of internal circuitry establish and continuously test for predetermined conditions under which a power operated door can be opened. A low speed detector (1) incorporates a micro-processor (8) and a no motion relay (3) to evaluate car and circuit operating conditions, providing control of all transit car doors. The micro-processor and associated control equipment also recognize predetermined failure modes. Occurrence of predetermined failure modes results in the overall system (1) reverting to a more conservative state. Coded indication (2) of failure modes is provided for easy indentification and corrective action by train operating crews.

Abstract: A lubricated split plug valve includes a valve body defining a chamber with fluid ports therethrough. A valve stem is rotatably mounted in the body and engages a split cylindrical valve member. The valve member includes a cylindrical passage with first and second inlets. The valve member includes a pair of core halves defined along an oblique plane passing through the cylindrical passage. Identical grooves for conveying sealant/lubricant to the plug/body interface are fabricated on the outer peripheral surfaces of the core halves with portions that substantially surround one of the passage inlets defined in the particular core half. Each groove also includes a continuous portion encircling the remaining outer periphery of each core half. Each groove is in fluid communication with a reservoir wherein lubricant may be introduced from a source into the groove. A piston is in each reservoir and biased under the influence of line pressure and gravity forces.

Abstract: A thermal storage heater system for heating fluids includes a storage tank for accumulating and storing energy in the form of a quantity liquid heated to a high temperature by an electric immersion heating element in the tank. A source of a first fluid to be heated is connected to the inlets of pilot and primary heat exchangers immersed in the high temperature liquid for transferring heat to the first fluid. A first circuit connects the outlet of the pilot heat exchanger to a point of use. A second fluid circuit connects the outlet of the primary heat exchanger to the point of use and includes a spring-loaded pressure sensitive check valve responsive to the flow rate in the first circuit for regulating the flow of fluid through the primary heat exchanger in response to a change in flow indicative of insufficient heating of the fluid by the pilot heat exchanger. The system includes an additional heat exchanger for heating a second fluid to be heated.

Abstract: A seal for an access door (44) mounted on a combustion chamber of a fluid heater includes a gasket pad (56) that is sealed to the interior surface of the door (52) by adhesive material. The gasket pad is secured to the door by first applying adhesive material to the interior surface of the door and the gasket pad. Thereafter, the gasket pad is attached to the coated area on the door covered by adhesive material.

Abstract: A pilot operated relief valve for use on medium and high pressure vessels, conduits, and the like.A two-stage, non-flowing valve (5) operates a main relief valve (7) of substantially greater capacity. Flow control elements provided by (35), (36), (38), and (39) associated with the first stage poppet are utilized to provide positive valve operation. In a preferred embodiment the main valve is mounted directly onto the pressure vessel which is to be vented at a predetermined pressure. The pilot is preferably mounted closely adjacent to and in fluid communication with the main valve. A flow adapter (100) having a self-cleaning orifice is disposed intermediate said main valve head volume (68) and pilot vent port (1) to provide improved operation of the combination. A ball (16) selector, (24, 15, 76) provides means for conveniently connecting to a field testing either the pilot or the entire valve, providing improved setpoint and reset or blowdown adjustments for the overall combination.

Abstract: A lift system for a transit vehicle includes a stationary main frame secured within a door recess of the vehicle and a side frame that is movable relative to the main frame. An articulated platform including steps pivotally secured to the side frame and scissor linkage pivotally and slideably connected to the main frame is also included. The lift system also includes a reaction switch coupled to the main frame to sense torque imparted to the main frame upon engagement of the platform with an obstacle such as a curb or the ground. If sufficient torque is created due to contact of the platform with an obstruction, the reaction switch is actuated to terminate further downward movement of the platform thereby preventing destruction of the system.

Abstract: A pilot operated relief valve for use on medium and high pressure vessels, conduits and the like.A two-stage, non-flowing valve (5) operates a main relief valve (7) of substantially greater capacity. Flow control elements provided by (35), (36), (38), and (39) associated with the first stage poppet are utilized to provide positive valve operation. In a preferred embodiment the main valve is mounted directly onto the pressure vessel which is to be vented at a predetermined pressure. The pilot is preferably mounted closely adjacent to and in fluid communication with the main valve. A flow adapter (100) having a self-cleaning orifice is disposed intermediate said main valve head volume (68) and pilot vent port (1) to provide improved operation of the combination. A ball (16) selector, (24, 15, 76) provides means for conveniently connecting to a field testing either the pilot or the entire valve, providing improved setpoint and reset or blowdown adjustments for the overall combination.

Abstract: A lubricated split plug valve includes a valve body defining a chamber with fluid ports therethrough. A valve stem is rotatably mounted in the body and engages a split cylindrical valve member. The valve member includes a cylindrical passage with first and second inlets. The valve member includes a pair of core halves defined along an oblique plane passing through the cylindrical passage. Identical grooves are fabricated on the outer peripheral surface of the core halves with portions that substantially surround one of the passage inlets defined in the particular core half. The groove also includes a continuous portion encircling the remaining outer periphery of each core half. Each groove is in fluid communication with a reservoir wherein lubricant may be introduced from a source into the groove. A piston is in each reservoir and biased under the influence of line pressure and gravity forces.

Abstract: A pilot operated relief valve for use on medium and high pressure vessels, conduits, and the like. A unique two-stage, non-flowing pilot valve operates a main relief valve of substantially greater capacity. In a preferred embodiment main valve is mounted directly onto the pressure vessel which is to be vented at a predetermined pressure. The pilot is preferably mounted closely adjacent to the main valve for operating communication therewith. A particularly unique ball selector provides means for testing both first and second stages without operating the main valve, providing improved setpoint and reset or blowdown adjustments for the overall combination.

Abstract: An air timing device for a high pressure reciprocating injector pump 14 employing a piston or movable wall 50 and orifice 48 combination that is mechanically reset on the suction stroke of the pump includes a bellows 42 defining a variable volume chamber 44 including at least one movable wall. An adjustable orifice 46 in parallel with a check valve is defined in the chamber to provide adjustable flow out of the chamber and full flow through the check valve into the chamber. The wall is connected to a piston 18 of the reciprocating pump by an arm 38 that is fixedly secured to the piston and slideably secured to the wall. A selector valve 62 is also included for directing supply fluid to a selected side of the pump piston to reciprocate the pump. The valve includes a spool valve connected to the wall by a second arm.

Abstract: A contactless pressure switch 10 sensitive to fluid pressure rates of change includes a housing 36 and a diaphragm 42 secured in the housing defining first and second chambers. Ports 48, 50 are included in the first and second chambers to vent the chambers. A magnet 52 is secured to the diaphragm and a switching module 54 is secured to the housing within one of the first or second chambers at a position spaced from the diaphragm. A biasing magnet 53 is mounted with the module to provide symmetrical switching by the module. The other of the first or second chambers is coupled to a sensing tube 28 such that upon a pulse or rate change of pressure being introduced in the other of first and second chambers, the diaphragm is deflected. This moves the magnet 52 toward the module actuating it to switch the module and actuate a desired circuit. In an alternative embodiment, the position of the module may be varied relative to the diaphragm to vary the sensitivity of the switch.

Abstract: A sensitive edge 10 for door systems, lifts, doors, or other moving portions of transit vehicles that come into contact with articles or passengers includes a body defining a resilient deformable leading edge portion 30 and a base portion 32 within which is defined an internal chamber. A coupling portion is defined on and extending from the base for coupling the sensitive edge to the door or similar device 36. The chamber 34 is hollow and at atmospheric pressure and in the preferred embodiment, is filled with air. Within the chamber is mounted a Wiegand wire and pick-up coil 38 that is electrically coupled to a switch for recycling the door or similar device upon engagement of the sensitive edge with an object such as a passenger.

Abstract: A load controller, primarily intended for use in systems having geographically distributed, energy utilizing loads, and employing stored energy heating apparatus. The controller (1, 10) disclosed, in conjunction with a stored energy heater (3, 4), when installed on an energy distribution system having a multiplicity of heaters and controllers, adjusts individual heater storage (3), providing adequate energy for varying heat requirements of individual heaters after a mandatory "off" period (46, 47, 49, 51), thereby greatly reducing the overall peak energy or demand requirements on a central energy source. Alternate embodiments utilize a microprocessor (300) to provide close control of heater storage and improve efficiency. Digital display (307) and a keyboard input are provided for adjusting system constants and evaluating unit operation.

Abstract: A pilot operated relief valve for use on medium and high pressure vessels, conduits, and the like.A unique two-stage, non-flowing pilot valve (5) operates a main relief valve (7) of substantially greater capacity. Flow control elements provided by 35, 36, 38, and 39 associated with the first stage poppet are utilized to provide positive valve operation. In a preferred embodiment the main valve is mounted directly onto the pressure vessel which is to be vented at a predetermined pressure. The pilot is preferably mounted closely adjacent to the main valve for operating communication therewith. A ball (16) selector, (24, 15, 76) provides means for conveniently connecting to a field testing either the pilot or the entire valve, providing improved setpoint and reset or blowdown adjustments for the overall combination.

Abstract: A system for controlling the kneeling operation of air suspension equipped transit vehicles includes air suspension members (20, 22, 24, 26, 28, 30) mounted at the wheels of the transit vehicle (10) and a fluid reservoir (32). A fluid circuit is included that communicates the reservoir with each of the air suspension members. An exhaust control valve (36) and a fluid flow control valve (150) are included in the circuit at each air suspension member. The system also includes a control valve for the front wheels of the vehicle and a by-pass valve (162) for by-passing the control valve (40) for the front wheels.

Abstract: A pilot operated pressure relief valve for use on medium and high pressure vessels, conduits, and the like. A two-stage, non-flowing pilot valve operates a main relief valve of substantially greater capacity. In a preferred embodiment the main valve is mounted directly onto the pressure vessel which is to be vented at a predetermined pressure. The pilot is preferably mounted closely adjacent to the main valve for operating communication therewith. An improved main valve seal is provided which allows the use of commonly available seal configurations in a simple and easily assembled construction to provide a fast operating, high pressure seal.

Abstract: A load controller, primarily intended for use in systems having geographically distributed, energy utilizing loads, and employing stored energy heating apparatus. The controller (1, 10) disclosed, in conjunction with a stored energy heater (3, 4), when installed on an energy distribution system having a multiplicity of heaters and controllers, adjusts individual heater storage (3), providing adequate energy for varying heat requirements of individual heaters after a mandatory "off" period (46, 47, 49, 51), thereby greatly reducing the overall peak energy or demand requirements on a central energy source.