Patent ID: 7311214

Claim:
A hoist cover assembly for use in a clean room; the assembly comprising: a hoist cover having a hoist cover cavity configured to receive a hoist body, said hoist cover comprising walls defining said hoist cover cavity, said walls configured to inhibit fluid communication between said hoist cover cavity and an exterior of said hoist cover walls; and a rigging cover having a rigging cavity configured to receive a rigging, the rigging coupled to the hoist body and an attaching member attachable to a load; said rigging cover suspended from said hoist cover and being extendable in response to an extension of the rigging from the hoist body and retractable in response to a retraction of the rigging when the hoist body is received in the hoist cover and the rigging is received in the rigging cavity; said rigging cover comprising a rigging cover wall defining said rigging cavity, said rigging cover wall configured to inhibit fluid communication between said rigging cavity and an exterior of said rigging cover wall; means for movably connecting said hoist cover to a support beam to allow said hoist cover and said rigging cover to be selectively located within the clean room; and an expansion chamber in fluid communication with said hoist body, said expansion chamber comprising a bladder expandable and contractible in response to a change of a volume of fluid in said hoist body.