Apparatus and method for the production of foods

Abstract

The invention relates to an apparatus and a method for the production of foods, in particular, a stuffing machine for the production of sausages, with a load circuit that generates a leakage current IA and with a filter, a frequency converter, a motor cable and a motor. The apparatus comprises a leakage current compensator with a device for detecting a leakage current and a device for generating a compensation current that is directed opposite to the leakage current and is superimposed with the leakage current, such that the leakage current is reduced, is in particular substantially eliminated.

1 . An apparatus for the production of foods, comprising:
 a load circuit that generates a leakage current;   an EMC filter;   a frequency converter;   a motor cable;   a motor;   a leakage current compensator with a device for detecting said leakage current; and   a device for generating a compensation current that is directed opposite to said leakage current and is superimposed with said leakage current, such that said leakage current is reduced.   
     
     
         2 . The apparatus according to  claim 1 , wherein said leakage current is substantially eliminated when superimposed with said compensation current. 
     
     
         3 . The apparatus according to  claim 1 , wherein said compensation current is shifted in its phase relative to said leakage current by 180° and has substantially a same amplitude as said leakage current. 
     
     
         4 . The apparatus according to  claim 1 , wherein said device for generating said compensation current comprises an amplifier and a capacitor network via which said compensation current is supplied to individual phases of a multi-phase system. 
     
     
         5 . The apparatus according to  claim 4 , wherein the individual phases of the multi-phase system comprises at least one of three phases of a three-phase system. 
     
     
         6 . The apparatus according to  claim 4 , wherein said leakage current compensator is arranged between a ground fault interrupter and said EMC filter. 
     
     
         7 . The apparatus according to  claim 4 , wherein said leakage current compensator is installed in a device upstream of said apparatus. 
     
     
         8 . The apparatus according to  claim 7 , wherein said apparatus further comprises a plug connected to said leakage current compensator by way of an outlet. 
     
     
         9 . The apparatus according to  claim 8 , wherein a power supply of said leakage current compensator is effected via a power supply of said apparatus. 
     
     
         10 . The apparatus according to  claim 8 , wherein said apparatus further comprises a delay device configured such that said compensation current is superimposed in a time-delayed manner. 
     
     
         11 . The apparatus according to  claim 10 , wherein said compensation current is superimposed in the time-delayed manner only when all phases of said plug have contacted when said apparatus is plugged in, and further wherein said delay device is optionally configured such that said capacitor network is switched on only when all phases of said plug have contacted when said apparatus is plugged in. 
     
     
         12 . The apparatus according to  claim 1 , wherein said leakage current compensator is integrated into said apparatus and is supplied via a separate auxiliary power supply. 
     
     
         13 . The apparatus according to  claim 12 , wherein said apparatus can be unplugged and is movable. 
     
     
         14 . The apparatus according to  claim 1 , wherein said apparatus is at least one apparatus from the following group: a stuffing machine for the production of sausages, a clipper, a spooling unit, a driven suspension unit, a cutter, a separation unit, a grouping unit, a conveyor belt, a charging system, and a packaging machine for food products. 
     
     
         15 . A method for the production of foods with an apparatus comprising a load circuit that generates a leakage current, the method comprising:
 detecting said leakage current during operation of said apparatus;   generating, with a leakage current compensator, a compensation current directed opposite to said leakage current; and   superimposing said compensation current onto said leakage current, whereby said leakage current is reduced and substantially eliminated.   
     
     
         16 . The method according to  claim 15 , wherein said leakage current compensator comprises an amplifier and a capacitor network, the method further comprising switching on said compensation current via said capacitor network in a time-delayed manner, when said apparatus is plugged in and only when all phases of a plug of said apparatus have contacted when plugged in. 
     
     
         17 . The method according to  claim 16 , wherein a power supply of said leakage current compensator is effected via a power supply of said apparatus, wherein said leakage current compensator is integrated into said apparatus and is supplied via a separate auxiliary power supply. 
     
     
         18 . The method according to  claim 17 , wherein said apparatus is unplugged, moved to another production location, and plugged in again. 
     
     
         19 . The method according to  claim 17 , wherein said leakage current compensator is arranged between a ground fault interrupter and an EMC filter of said apparatus. 
     
     
         20 . The method according to  claim 19 , wherein said apparatus is supplied with voltage via a three-phase mains with three phases, further comprising:
 detecting a current in the three phases;   feeding corresponding signals to an amplifier comprising an evaluation unit;   determining, with the evaluation unit, a respective leakage current by subtraction; and   generating, with the evaluation unit, a compensation current which is fed via a capacitor network to at least one of the three phases.