Fast-responsive electromagnetic balance-type weighing apparatus
US5367128A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 8, 1991 |
| Grant date | Nov 22, 1994 |
| Priority date | — |
| Expiry date | May 8, 2011 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01G7/04
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A novel electromagnetic balance-type weighing apparatus according to the invention includes a weighing pan/balance beam assembly (15) whose balance beam is angularly displaced as a function of the weight of an object of weighing placed on the weighing pan. An electromagnetic coil (9) is provided to generate an electromagnetic force that offsets the displacement of the balance beam of the weighing pan/balance beam assembly (15) caused by the weight of the object of weighing. A displacement detector (3, 4, 5) is provided to detect the displacement of the balance beam of the weighing pan/balance beam assembly (15). An operation unit (7) performs operations to determine a control voltage in response to the detection signal transmitted from the displacement detector (3, 4, 5). A current transducer circuit (20) generates an electric current in response to the control voltage applied to it by the operation unit (7) and supplies it to the electromagnetic coil (9). The current transducer circuit (20) comprises a negative feedback loop circuit for feeding the output current from said current transducer circuit (20) back to the input terminal of the current transducer circuit (20). A weight c…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.