Rubber spring for furrow opener
US4448259A · kind A · utility
6Cited by
9References
12Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Apr 19, 1982 |
| Grant date | May 15, 1984 |
| Priority date | — |
| Expiry date | Apr 19, 2002 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02A40/22
- WIPO fieldOther special machines
- WIPO sectorMechanical engineering
Abstract
A pre-stressed columnar rubber spring interposed between the pressure beam and pivoted draw bar tube of a no-till seed drill deflects under load in one direction only and the force causing increased spring deflection in the principle operational range increases to a desired maximum and then remains substantially constant or decreases slightly thereby relieving the machine of excess stresses caused by contact of coulters and openers with rocks and other field obstructions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.