Abstract: There is a gear rotor for use in a positive displacement flowmeter of the type described. The rotor has an external wall profile 8 forming three equally spaced lobes 9 and a partially open core structure inside said profile with internal cavities 15, 15A defined between webs 13, 14 extending from a central hub 12 of said rotor to said wall profile 8.

Abstract: There is a positive displacement flowmeter having a pair of rotors 11 rotatable on spaced apart parallel axis 14 within a housing 8 between inlet and outlet chambers 9, 10. The rotors have gear teeth 18 and are meshed together to rotate in accordance with volumetric fluid flow through the meter from the inlet chamber 9 to the outlet chamber 10. Each of the rotors has three lobes with rotor profiles between adjacent lobes being concave.

Abstract: There is a lock for a bi-directional door, swing or sliding door 19. The lock includes at least two pins 6, 7 which are spaced apart a distance exceeding the thickness of the door. The pins are adapted for simultaneous arcuate motion about an axis located between said pins 6, 7 and longitudinal movement between withdrawn and protruding positions. When the lock is in a configuration of use and the pins 6, 7 are moved from the withdrawn positions to the protruding positions an edge of the door 19 when placed at a location offset from the axis is engaged by at least one of said pins 6, 7 so that the door is secured at a position substantially over the axis.

Abstract: There is an electric motor driven drop bolt having a housing which in use is mounted into a doorway frame and has the bolt pivotal therein by a mechanical drive set in a cage disposed at an operative position. The bolt is pivotal between a locking configuration where the bolt extends outward of the housing to engage in an aperture associated with a door within the frame and an unlocked configuration where the bolt is withdrawn to clear the aperture. The mechanical drive includes a screw shaft rotatable by the electric motor to move a roller nut along the length of the shaft whilst engaging a cam surface on the bolt. To obtain fail safe operation of the drop bolt the cage is slidable in the housing from the operative position to a disengaged position so that the bolt is movable from the locking configuration to the unlocked configuration without operation of the mechanical drive.

Abstract: There is an electric motor driven drop bolt having a housing which in use is mounted into a doorway frame and has the bolt pivotal therein by a mechanical drive set in a cage disposed at an operative position. The bolt is pivotal between a locking configuration where the bolt extends outward of the housing to engage in an aperture associated with a door within the frame and an unlocked configuration where the bolt is withdrawn to clear the aperture. The mechanical drive includes a screw shaft rotatable by the electric motor to move a roller nut along the length of the shaft whilst engaging a cam surface on the bolt. To obtain fail safe operation of the drop bolt the cage is slidable in the housing from the operative position to a disengaged position so that the bolt is movable from the locking configuration to the unlocked configuration without operation of the mechanical drive.

Abstract: There is a lock release apparatus for providing delayed passage past a movable barrier such as an exit door which is held to a closed position by a lock. The apparatus includes a beam transmitter, a beam receiver, a timer for releasing the lock after a predetermined delay, a trigger associated with the timer and a beam reflector affixed to an operating bar on the movable barrier. In use of the apparatus when the barrier is closed and locked the transmitter directs a beam onto the reflector at an orientation such that reflection is detected by the beam receiver when the operating bar is undisturbed. Subsequent movement of the operating bar to open the barrier terminates or shifts the reflection away from the receiver to trigger the timer to release the lock after the predetermined delay.

Abstract: There is a lock release apparatus for providing delayed passage past a movable barrier such as an exit door which is held to a closed position by a lock. The apparatus includes a beam transmitter, a beam receiver, a timer for releasing the lock after a predetermined delay, a trigger associated with the timer and a beam reflector affixed to an operating bar on the movable barrier. In use of the apparatus when the barrier is closed and locked the transmitter directs a beam onto the reflector at an orientation such that reflection is detected by the beam receiver when the operating bar is undisturbed. Subsequent movement of the operating bar to open the barrier terminates or shifts the reflection away from the receiver to trigger the timer to release the lock after the predetermined delay.

Abstract: There is a lock for a gaming machine or other device. The lock has a plug 3 rotatable in a cylinder 1 between latched and unlatched positions. There are rolling members 9, 9A which at the latched position are radially displaceable within aligned plug and cylinder recesses 10, 11 between an outer locking position wherein said rolling member extends across a shear face 10A separating said plug 3 and cylinder 1 to hold the plug in the latched position and an inner unlocked position wherein the rolling members 9, 9A are substantially within the plug recess 10. There is a plunger movable axially within the plug 3 between a first position wherein the rolling members 9, 9A are retained in the locking position and a second position in which the rolling members 9, 9A are movable inward from the locking position to the unlocked position to allow rotation of the plug 3 from the latched to the unlatched positions.

Abstract: There is a lock for a door or the like which comprises a tongue pivotable on an axis between a locking position where it engages a striker and an unlocked position where it is clear of the striker. A pawl is pivotable on a second axis between a first position where one end abuts said tongue to hold it in said locking position and a second position where said one end is clear of the tongue. There is a set of toggles hingedly connected end to end between another opposite end of the pawl and another axis. The interconnected ends of the toggles are connected to a solenoid plunger by a link. There is a stop pin which is movable between a fail safe position where when the solenoid is deactivated the toggles are biased by a coil spring against the stop pin in a substantially straight configuration and a fail safe position where during energization of the solenoid the toggles are held to a slightly offset position against the stop pin.