Abstract: An air heater with a safety control circuit is disclosed. A heat source is mounted within a hollow housing having an air inlet end and an air outlet end. The heat source is actuated in response to the presence of a heat control signal. The heat control signal is produced when both a predetermined minimum pressure differential between static air pressure outside the hollow housing and the air velocity pressure within the housing is reached and the temperature of a portion of the housing is lower than a predetermined maximum sensed temperature. Application of the heat control signal to the heat source can be manually initiated or interrupted.

Abstract: A gas flow amplifier has a housing defining an axially extending cylindrical chamber. A hollow truncated conical diffuser diverges outwardly from one end of the chamber, and a high pressure primary gas is introduced into the chamber at its opposite end in a manner such as to entrain a flow of ambient secondary gas into the chamber, and to cause the thus introduced primary gas and entrained secondary gas to exit from the chamber and into and through the diffuser.

Abstract: A shaft is rotatably journalled in a bearing assembly. The shaft has a sleeve fixed thereon at a location axially adjacent to the bearing assembly, and a ring depends from the sleeve into a supply of liquid lubricant contained in an underlying sump. Rotation of the shaft and sleeve causes the ring to rotate about its own axis, and the rotating ring carries lubricant upwardly from the sump, with the thus carried liquid ultimately being returned to the sump by a combination of centrifugal and gravitational forces. A dam is interposed between the underside of the sleeve and the ring depending therefrom to direct a substantial and continuous flow of the returning lubricant to the bearing assembly.

Abstract: A rotary burner has fuel discharge nozzles arranged exclusively in the high velocity zone of combustion air flow. The resulting annular flame pattern has a central region adjacent to the burner hub which is essentially combustion free.

Abstract: An overspeed trip mechanism for a rotating shaft has a collar mounted on the shaft. An eccentric ring surrounds and is connected to the collar for rotation therewith. A trip member is located exteriorly of the collar. The eccentric ring is movable radially relative to the collar between a first position spaced from the trip member and a second position in contact therewith. A spring is arranged between the ring and the collar to yieldably urge the ring into its first position.