Lift unit for weight distributing trailer hitch
US4815752A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 2, 1987 |
| Grant date | Mar 28, 1989 |
| Priority date | — |
| Expiry date | Dec 2, 2007 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T403/608
- WIPO fieldTransport
- WIPO sectorMechanical engineering
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 ed…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.