Speed responsive coupling device especially for fall arrest apparatus

A speed responsive coupling device of the type which selectively locks a first member against rotation in at least one direction relative to a second member, comprising:

• a ratchet wheel secured to the first member;
• a pawl mounted on the second member and movable relative thereto between a first position, wherein the ratchet wheel remains free to rotate in the one direction relative to the pawl and the second member, and a second position, wherein the ratchet wheel is locked against rotation in the one direction relative to the pawl and the second member, wherein the pawl includes a nose portion, a tail portion, and an intermediate portion disposed therebetween, and the intermediate portion is rotatably mounted to the second member;
• and
• a resilient member and interconnected between the pawl and the second member in such a manner that the resilient member biases the pawl to remain in the first position and also biases the pawl to remain in the second position, wherein the tail portion bears against the ratchet wheel as the ratchet wheel rotates in the one direction relative to the pawl and the second member, and when the ratchet wheel rotates at sufficient speed, its impact against the tail portion overcomes the bias of the resilient member and causes the nose portion to bear against the ratchet wheel.

A fall arrest apparatus, comprising:

• a base;
• a drum rotatably mounted on the base;
• a safety line wound about the drum;
• a locking means, interconnected between the base and the drum, for selectively locking the drum against rotation in at least one direction relative to the base;
• and
• a toggled biasing means, interconnected between the base and the locking means, for biasing the locking means to remain in an unlocked position, and for biasing the locking member to remain in a locked position.

A fall arrest apparatus, comprising:

• a base;
• a drum rotatably mounted on the base;
• a safety line wound about the drum;
• a braking means, interconnected between the base and the drum, for selectively resisting rotation of the drum in at least one direction relative to the base;
• and
• a toggled biasing means, interconnected between the base and the braking means, for biasing the braking means to remain in an inoperative condition, and for biasing the braking means to remain in an operative condition.