Mechanical linear lock with redundant locking feature

In a fail-safe latch for a linear mechanical lock of the type having a rod axially translatable through a lock housing, a coil spring normally gripping the rod against such axial movement and lock release means actuatable for unwinding the coil spring thereby to free the rod for said axial movement, the improvement comprising:

• back-up latch means mounted for movement towards and away interlocking engagement between said rod and said housing;
• first means normally urging said latch means towards said interlocking engagement thereby to hold said rod against said axial movement independently of said coil spring;
• and
• second means operatively connected for first disengaging said latch means upon actuation of said lock release means before unwinding said coil spring thereby to free said rod.

In a fail-safe latch for a linear mechanical lock of the type having a rod axially translatable through a lock housing, a coil spring normally gripping the rod against such axial movement, sleeve means rotatable about said rod for unwinding said coil spring responsive to actuation of lock release means thereby to free the rod for said axial movement, the improvement comprising:

• back-up latch means including a toothed pawl pivoted to said housing for movement towards and away from interlocking engagement with a grooved section of said rod;
• spring means normally urging said latch means towards said interlocking engagement thereby to hold said rod against said axial movement independently of said coil spring;
• and
• cam means on said rotatable sleeve and cam follower means operative for disengaging said backup latch means from said rod upon rotation of said sleeve to a rod releasing position.

In a fail-safe latch for a linear mechanical lock of the type having a rod axially translatable through a lock housing, a coil spring normally gripping the rod against such axial movement, sleeve means rotatable about said rod for unwinding said coil spring responsive to actuation of lock release means thereby to free the rod for said axial movement, the improvement comprising:

• back-up latch means mounted for movement towards and away from interlocking engagement between said rod and said housing;
• cam means on said rotatable sleeve;
• cam follower means arranged and connected for disengaging said back-up latch means upon rotation of said sleeve to a rod releasing position;
• and
• a loading coil spring having two end tangs, one said tang urging said back-up latch means towards engagement with said rod, thereby to hold said rod against said axial movement independently of said coil spring, the other of said tangs urging said cam follower means into camming relationship with said cam means.

In a fail-safe latch for a linear mechanical lock of the type having a rod axially translatable through a lock housing, coil spring means fixed to the housing and normally gripping the rod against such axial movement and coil release means actuatable for unwinding the coil spring thereby to free the rod for said axial movement, the improvement comprising:

• a transversely grooved section on said rod;
• toothed latch means mounted to said housing for movement towards and away from engagement with said grooved rod section;
• means normally urging said latch means towards positive engagement with said rod thereby to lock said rod to said housing even in the event of failure of said coil spring;
• and
• main lever means rotatable on said lock housing to a first position for first disengaging said latch means and for then actuating said coil release means upon further rotation of said main lever means thereby to free said rod.

In a fail-safe latch for a linear mechanical lock of the type having a rod axially translatable through a lock housing, coil spring means fixed to the housing and normally gripping the rod against such axial movement, sleeve means rotatable about said rod, and a first lever fixed to said sleeve, the improvement comprising:

• a transversely grooved section on said rod;
• toothed latch means mounted to said housing for movement towards and away from engagement with said grooved rod section;
• means normally urging said latch means towards positive engagement with said rod thereby to lock said rod to said housing even in the event of failure of said coil spring;
• a rotatable spindle on said housing transversely to said rod;
• and
• a second lever on said spindle mounted externally to said lock housing including first means for first disengaging said latch means upon rotation of said spindle to a first position, and second means operative for rotating said rotatable sleeve means upon further spindle rotation.