05074423 is referenced by 5 patents and cites 25 patents.

A low-profile lifting apparatus (10) for hoisting and moving objects along an I-beam (12), comprising a frame assembly (20), a drive system (44), a pulley assembly (56), and a hoist assembly (66). The drive system (44) includes a first drive roller (48), and a second drive roller (49) operatively connected to each other and positioned on opposite sides of the web (14) to drive the lifting apparatus (10) along the lower flange (16). The drive mechanism (50) includes a pulley chain (62) that is manually pulled by an operator to rotate the drive shaft (60) and the attached drive rollers (48) and (49). A block (74) has a hook (76) positioned laterally on one side of the lateral centerpoint (82) nearest the chain hoist (68). The load chain (86) passes downward from the frame assembly (20) to the pulley wheel (78), then back to the frame assembly (20), and laterally beneath the lower flange (16) to the frame assembly (20), then down to the pulley wheel (80) on the block (74), then back to the frame assembly (20) where it engages the chain hoist (68).

Title
Low-profile lifting apparatus
Application Number
358709
Publication Number
5074423
Application Date
April 11, 1991
Publication Date
December 24, 1991
Inventor
Glenn S Smith
Issaquah
WA, US
Agent
Christensen O Connor Johnson & Kindness
Assignee
Ingersoll Rand Company
NJ, US
IPC
B66C 11/16
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