Electronic scales with two ranges
US4307787A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 24, 1980 |
| Grant date | Dec 29, 1981 |
| Priority date | — |
| Expiry date | Jun 24, 2000 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01G23/005
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In order to obtain, in an electronic balance, ranges which are in a predetermined ratio, for example 1:10, there is provided a measuring arm provided with strain gauges adapted to measure the deformation of this arm when it is subjected to a constraint or force. Between the arm and a knife-edge there is disposed a measuring annulus likewise provided with strain gauges adapted to measure the deformation of this annulus when it is subjected to a weighing force. The balance is operated in such a manner that the force or mass of the weight to be measured at the moment of weighing is exerted firstly on the arm via the annulus, until the arm contacts the abutment. This determines the small measuring scale. If the weight is higher than this value, the force is subsequently exerted solely on the annulus which presents a resistance in the region of 10 times greater and determines the second measuring scale.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.