The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 28, 1989
Filed:
Dec. 02, 1987
David A Young, Plymouth, MI (US);
James L Mellow, Birmingham, MI (US);
The Fisher Group, Inc. (Draw-Tite Division), Canton, MI (US);
Abstract
The lift unit comprises a bracket portion that is secured to the trailer tongue and a hinge portion that pivots on the bracket portion about a horizontal axis to raise and lower a chain for flexing and relaxing a spring bar that when flexed, serves to transfer a portion of the tongue weight to the towing vehicle. A flat rectangular member is eccentrically mounted on the side of the hinge portion to hang in the 6:00 o'clock position unless acted upon by influences other than gravity. When the hinge portion is operated to raise the chain and thereby flex the spring bar, a longer side of the rectangular member abuts and rides along the edge of a side of the bracket portion resulting in the member being swung clockwise to about the 8:00 o'clock position when full chain elevating position is reached. At this time one corner of the member drops into a notch in the bracket portion and prevents the hinge portion from being operated in the direction of chain lowering. The member is kept in this position by passing a tethered pin through the member and the hinge. When the pin is removed, the member can be swung further clockwise to about 4:00 o'clock to enable the chain to be lowered. The edge of the bracket's side acts on the member during chain lowering to swing the member counterclockwise back to 6:00 o'clock thereby automatically resetting the member for automatic locking when the chain is again raised.