Patent ID: 9086315
Filing Date: 2015-07-21
Classification: G01G

Abstract:
1. A weighing cell based on the principle of electromagnetic force compensation, comprising a stationary base part; a load receiver constrained to the base part in guided movement and serving to receive the weight force of a weighing load; a permanent magnet system mounted on the base part, said permanent magnet system having an air gap; a coil suspended in the air gap with guided mobility and adapted to conduct an electrical compensation current when the weighing cell is in operation; a deflectable force-transmitting mechanism connecting the load receiver to the coil; a first carrier element rigidly attached to a first attachment surface of the base part by way of two spaced apart fastening locations that are aligned on a common axis of the first carrier element; a second carrier element rigidly attached to a second attachment surface of the base part by way of two spaced apart fastening locations that are aligned on a common axis of the second carrier element; an optoelectronic position sensor comprising a light emitter and a light receiver that are mounted to the base part on opposite sides of a separating interstitial space, and a shutter vane that traverses said interstitial space and participates in the movement of the coil, the light emitter being mounted midway between the two fastening locations of the first carrier element and on the common axis thereof, and the light receiver being mounted midway between the two fastening locations of the second carrier element and on the common axis thereof, a sensor signal of the optoelectronic position sensor being representative of the deflection of the coil from a zero position which occurs as a result of placing a load on the load receiver; and a closed-loop controller which, in response to the sensor signal, regulates the compensation current in such a way that the coil and the load receiver that is connected thereto are returned to their zero position by the electromagnetic force that is acting between the coil and the permanent magnet; wherein the first attachment surface of the base part and the second attachment surface of the base part face the same direction such that the first carrier element and the second carrier element are installable from the same side of the base part.