The engineer's sketch-book of mechanical movements, devices, appliances, contrivances and details employed in the design and construction of machinery for every purpose

by Thomas Walter Barber

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Section 81.—SAFETY APPLIANCES FOR VARIOUS USES.

FOR HOIST CAGES, &c.

[1492]. Cam gear; operates by gripping the wood guides by a serrated eccentric cam surface on the breakage of the rope, the cam being pulled round by a spring which is kept out of action by the tension of the rope until it breaks.

[1493]. Strut or pawl gear; explains itself.

[1494]. Double wedge gear.

[1495]. Governor gear. The rope attached to the cage drives a governor acting on a brake or catch which is thrown into action if the cage gains excessive speed, used in Attwood Beaver’s Patent; American Elevator Co., &c.

[1496]. Rack and pawl gear.

[1497]. Cross grip lever gear.

[1498]. Safety hook to prevent accident from overwinding; the projecting horns A A strike the edges of the plate B, and throw the shackle C at top out of gear.