Abstract: A barrier release mechanism for a construction including a barrier and frame has a latch biased towards an unlatching position. An actuation device adjacent the construction is movable, under pressure from a fluid pressure source, into an engaged position in abutment with the latch to urge the latch against the bias to cause constraining of the barrier. Reduction of the pressure allows the actuation device to move to a disengaged position wherein the bias moves the latch to the unlatching position in which the barrier is not constrained.

Abstract: A barrier release mechanism for a construction including a barrier and frame has a latch biased towards an unlatching position. An actuation device adjacent the construction is movable, under pressure from a fluid pressure source, into an engaged position in abutment with the latch to urge the latch against the bias to cause constraining of the barrier. Reduction of the pressure allows the actuation device to move to a disengaged position wherein the bias moves the latch to the unlatching position in which the barrier is not constrained.

Abstract: A pneumatically operated barrier lock is provided. The barrier lock includes a body and a locking pin slidably mounted on the body for movement along a path between an extended position for engaging a catch and a retracted position for disengaging the catch. The lock also includes a pneumatic cylinder in connection with a pressure source and actuating the locking pin between the extended position and the retracted position. An opposite end of the cylinder is adapted for connection to a relatively low second pressure source. A second pressure source connectable to end of the pneumatic cylinder biases the piston away therefrom and generates a first biasing apparatus, in form of a pneumatic spring, which biases the locking pin toward the retracted position. A blocking member is hingedly connected, about a pivot axis, to the body and is selectively movable between a first position and a second position.

Abstract: A barrier release mechanism (1) for a barrier (3) including at least one barrier latch (170), a latch actuation device (7) disposed adjacent the barrier (3) and coupled to the barrier latch (170), the latch actuation device being movable between an engaged position in which the latch actuation device (7) causes the barrier latch to be engaged thereby latching the barrier (3) and a disengaged position in which the latch actuation device (7) causes the barrier latch (17) to disengage thereby allowing the barrier (3) to be moved, the latch actuation device (7) being resiliently biased by a spring (6) into the disengaged position. A source of fluid pressure is in fluid communication with the latch actuation device (7) and a pressure control valve disposed intermediate the latch actuation device and the source of fluid pressure.