Fine grader
US4249327A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Mar 26, 1979 |
| Grant date | Feb 10, 1981 |
| Priority date | — |
| Expiry date | Mar 26, 1999 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE02F3/8155
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
A fine grader for fine grading the surface of the subgrade on which fresh concrete is to be poured to form a uniformly level surface for receiving freshly poured concrete is formed by coupling together a fine grader attachment with a vibratory screed. The screed includes first and second ends and first and second end brackets which are coupled to the first and second ends of the screed frame. A winch is coupled to each end bracket for translating the screed along the length of the side forms. The fine grader attachment for the screed includes a fine grader blade, a series of brackets coupled to the screed frame and to the fine grader blade for maintaining the blade in a grading position below and in front of the screed. A plurality of pneumatic motors impart a vibratory motion to the frame while a network of brackets and struts transmits the vibratory motion of the frame to the fine grader blade to permit the vibratory motion of the fine grader blade against the surface of the subgrade to form a uniformly level surface as the frame is translated along the length of the side forms.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.