Adjustable side draft indicator
US4989327A · kind A · utility
Inventor
Key dates
| Filing date | Nov 13, 1987 |
| Grant date | Feb 5, 1991 |
| Priority date | — |
| Expiry date | Nov 13, 2007 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB62D15/02
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A transparent shape retentive and flexibly resilient tubular member is supported from a farm tractor in an upstanding plane disposed transverse to the tractor and is vertically bowed. The interior of the tubular member includes gravity responsive indicator structure disposed therein and movable therealong to a longitudinal center position within said tubular member responsive to gravity forces when the vehicle is laterally horizontally disposed and movable, proportionally along the tubular member from a central position therein toward opposite ends of the tubular member responsive to lateral tilting of the tractor in opposite directions and structure is provided to adjustably vary the radius of curvature of the arcuate tubular member.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.