Calibration of crane load indicating arrangement
US4063649A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 5, 1975 |
| Grant date | Dec 20, 1977 |
| Priority date | — |
| Expiry date | Nov 5, 1995 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01L25/00
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A device for the calibration of the safe load indicating apparatus on cranes and derricks that have a pivoted, extensible boom luffed by a hydraulic ram. The device operates by combining electrical signals corresponding to the actual turning moment of the unloaded boom at given boom positions with generated calibration signals corresponding to the turning moment for the theoretical maximum load at the boom positions, by comparing these combined signals to the safe load signals from the crane's law generator unit and by adjusting the law generator unit accordingly. This invention relates to a method and apparatus for the calibration of safe load indicating apparatus for use with cranes, derricks and other lifting apparatus of the type having a pivoted, extensible boom which can be luffed by an hydraulic ram or other boom supporting means. It has particular but not exclusive application to the calibration of safe load indicating apparatus used on mobile cranes having an extensible boom which can be slewed through the whole or part of a circle. A typical mobile crane has a boom comprising a plurality of telescoping sections, of which the lowermost is pivoted to a base unit for luffing…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.