Method and apparatus for gravimetrically metering pourable or flowable material to be weighed

Abstract

An apparatus and a method for gravimetrically metering pourable or flowable material to be weighed are provided. A container holds the material to be weighed and a weighing device detects the weight of the container. A first actuator fills the container located on the weighing device with the material to be weighed and a second actuator empties the container or places the empty container on the weighing device. Further, a control device for generating control signals for the actuators is provided. A signal filter with a variable filter characteristic filters the weighing signal delivered by the weighing device. A filter matching device, controlled by the control device, matches the filter characteristic as a function of the control signals to various predetermined filter characteristics.

1 .- 18 . (canceled) 
     
     
         19 . An apparatus for gravimetrically metering pourable or flowable material to be weighed, comprising:
 a container for holding the material to be weighed;   a weighing device for detecting the weight of the container;   a first actuator for filling the container located on the weighing device with the material to be weighed;   a second actuator for emptying the container located on the weighing device or for placing the empty container on the weighing device;   a control device for generating control signals for the actuators;   a signal filter with a variable filter characteristic for filtering the weighing signal delivered by the weighing device; and   a filter matching device, controlled by the control device, for matching the filter characteristic as a function of the control signals to various predetermined filter characteristics.   
     
     
         20 . The apparatus as claimed in  claim 19 , wherein the signal filter is a low-pass filter. 
     
     
         21 . The apparatus as claimed in  claim 19 , wherein the filter characteristic is varied relative to the limit frequency. 
     
     
         22 . The apparatus as claimed in  claim 20 , wherein the filter characteristic is varied relative to the limit frequency. 
     
     
         23 . The apparatus as claimed in  claim 19 , wherein the signal filter is a mean-value filter with a filter characteristic and a filter width, the filter characteristic being varied relative to the filter width. 
     
     
         24 . The apparatus as claimed in  claim 19 , wherein the filter characteristic is changed relative to a filter type and/or filter arrangement. 
     
     
         25 . The apparatus as claimed in  claim 19 , wherein the filter matching device is configured to change a limit frequency of the signal filter, designed as a low-pass filter, from a predetermined higher value to a predetermined lower value within a predetermined time immediately after the filling of the container with the material to be weighed. 
     
     
         26 . The apparatus as claimed in  claim 19 , wherein the filter matching device is configured to change a limit frequency of the signal filter, designed as a low-pass filter, from a predetermined higher value to a predetermined lower value within a predetermined time immediately after emptying the container or after placing the empty container on the weighing device. 
     
     
         27 . The apparatus as claimed in  claim 19 , wherein the filter matching device is configured to change a filter width of the signal filter, designed as a mean-value filter, from a predetermined lower value to a predetermined higher value within a predetermined time immediately after the filling of the container with the material to be weighed. 
     
     
         28 . The apparatus as claimed in  claim 19 , wherein the filter matching device is configured to change a filter width of the signal filter, designed as a mean-value filter, from a predetermined lower value to predetermined higher value within a predetermined time immediately after the emptying of the container or after placing the empty container on the weighing device. 
     
     
         29 . A method for gravimetrically metering pourable or flowable material to be weighed, comprising:
 providing a container located on a weighing device;   filling the material to be weighed into the container by a first controllable actuator;   emptying the container by a second controllable actuator or placing the container on the weighing device by the second controllable actuator;   determining a weight of the container by the weighing device;   delivering a weighing signal by the weighing device;   passing the weighing signal through a signal filter,   wherein a filter characteristic of the signal filer is changed and matched to different predetermined filter characteristics as a function of control inputs of the actuators.   
     
     
         30 . The method as claimed in  claim 29 , wherein the weighing signal is low-pass filtered in the signal filter. 
     
     
         31 . The method as claimed in  claim 29 , wherein the filter characteristic is changed relative to the limit frequency. 
     
     
         32 . The method as claimed in  claim 30 , wherein the filter characteristic is changed relative to the limit frequency. 
     
     
         33 . The method as claimed in  claim 29 , wherein the weighing signal is averaged in the signal filter designed as a mean-value filter, and the filter characteristic is changed relative to a filter width of the signal filter. 
     
     
         34 . The method as claimed in  claim 29 , wherein the filter characteristic is changed relative to a filter type and/or filter arrangement. 
     
     
         35 . The method as claimed in  claim 29 , wherein, immediately after filling the container with the material to be weighed, a limit frequency of the signal filter designed as a low-pass filter is changed from a predetermined higher value to a predetermined lower value within a predetermined time. 
     
     
         36 . The method as claimed in  claim 29 , wherein, immediately after the emptying of the container or after the placing of the empty container on the weighing device, a limit frequency of the signal filter designed as a low-pass filter is changed from a predetermined higher value to a predetermined lower value within a predetermined time. 
     
     
         37 . The method as claimed in  claim 29 , wherein, immediately after the filling of the container with the material to be weighed, a filter width of the signal filter designed as a mean-value filter is changed from a predetermined lower value to a predetermined higher value within a predetermined time. 
     
     
         38 . The method as claimed in  claim 29 , wherein, immediately after the emptying of the container or after the placing of the empty container on the weighing device, a filter width of the signal filter designed as a mean-value filter is changed from a predetermined lower value to a predetermined higher value within a predetermined time.