US Patent 7513139 Electronic balance having a calibration weight arrangement

The calibration weight arrangement for an electronic balance with a force-transmitting device (1), includes a calibration weight (14) capable of coupling to the force-transmitting device (1). The calibration weight (14) is moved vertically by a transfer mechanism and a drive source to establish and to release the force-transmitting contact between the calibration weight (14) and the force-transmitting device (1). The transfer mechanism has at least one resetting element (22, 37, 38, 40, 43) and a lifting system configured as a knee joint linkage (17, 117, 217). The resetting element (22, 37, 38, 40, 43) and the lifting system work together to arrest and cushion the calibration weight (14) if the balance is shocked, dropped or hit.