Abstract: A method of locking, unlocking and monitoring doors using a computer and a computer software program, electro-locking devices, power-line carrier components and existing AC wiring from the door sites to the computer is provided.The computer program changes the status of each door according to predetermined schedule and displays the locked/unlocked/ajar status of each door as well as the event change (Push bar/key/fire alarm).Exits are fitted with electro-door locks with sensor capabilities and are monitored from the computer via power line carrier components. At each exit site, a receiver receives commands from the computer and changes the locking status while a transmitter at the door site reports every changed status back to the computer. A microprocessor at each door site can control the doors and operate via battery back-up in a power failure or when communication from the computer program is interrupted. A transmitter at the fire alarm panel causes all doors to unlock if the fire alarm is activated.

Abstract: A small gas turbine engine having a small, high speed shaft assembly including a central shaft member, a radial outflow compressor rotor secured to one end of the central shaft member with its inlet end disposed outboard of the shaft assembly, and a radial inflow turbine rotor secured to the other end of the central shaft member with its discharge end disposed outboard of the shaft assembly. The shaft assembly is supported at its ends, outboard of the rotors, by a pair of bearings which are axially secured but allow limited radial movement of the shaft assembly. An annular combustor is disposed between the turbine and compressor rotors in encircling relation to the central shaft member. Fuel is supplied to the combustor chamber from the exhaust end of the turbine through an axial passage in the shaft assembly opening at one end outboard of the exhaust end bearing and communicating at its other end with radial ports in the central shaft member arranged to sling fuel into the combustor chamber.

Abstract: A sealing ring for computer tape reels and the like wherein the sealing ring comprises a molded unitary strip of homogeneous plastics material adapted to be formed into a loop to sealingly encircle the reel. The strip has a live transverse hinge adjacent one strip end defining a latch portion between the hinge and that end, and a transverse seating surface is provided on the radially inner side of the strip adjacent the hinge. In use, the strip is wrapped around the reel, the transverse end surface of the other end of the strip, remote from the latch portion, is abutted against the transverse seating surface to dispose the latch portion in overlapping relation to the other strip end, and the latch portion is pivoted inwardly about the hinge axes to latchingly interengage latching elements defined on the radially inner surface of the latch portion and on the overlapped portion of the other strip end.