Modular batch weighing control system and method

Claim 3

A method in accordance with claim 1 wherein said step of generating a pulse train signal having a number of pulses proportional to the difference between said predetermined set point value and the digital signal produced by weighing said container includes the steps of: stepping a third counter in response to a clock signal; stepping a fourth counter in response to said clock signal; detecting a coincidence between the count in said third counter and said predetermined set point value; detecting a coincidence between the count in said fourth counter and the digital signal produced by weighing said container; and gating said clock signal during the time interval between the detection of said coincidences to produce said first pulse train signal.

Claim 4

A method in accordance with claim 1, including the steps of: generating a third pulse train signal having a number of pulses proportional to the digital signal produced by weighing said container; applying said third pulse train to a fifth counter; comparing the count in said fifth counter with a predetermined zero tolerance value; and generating a third output signal when the count in said fifth counter does not exceed said predetermined zero tolerance value.

Claim 5

A method in accordance with claim 3, including the step of applying said third output signal to a first indicator means.

Claim 6

A method in accordance with claim 1, including the steps of: applying said first pulse train signal to a sixth counter; compAring the count in said sixth counter with a predetermined cutoff tolerance value; and generating a fourth output signal when the count in said sixth counter does not exceed said predetermined cutoff value.

Claim 7

A method in accordance with claim 5 including the step of applying said fourth output signal to a second indicator means.

Claim 8

Apparatus for batch weighing material fed by a feeder into a container, said feeder having a control means for providing a first and a second feed rate, said first feed rate being greater than said second feed rate, comprising: means for weighing said container, said weighing means producing a digital signal indicative of the weight of the material in said container; means for generating a first pulse train signal having a number of pulses proportional to the difference between a predetermined set point value and the digital signal produced by said weighing means; a first counter for counting the pulses in said first pulse train; means for dividing said first pulse train by a first predetermined number to obtain a second pulse train; a second counter for counting said second pulse train; means for comparing the count in said second counter with a predetermined primary cutoff value and producing a first output signal when the count in said second counter does not exceed said predetermined primary cutoff value, said first output signal being applied to said control means to cause said control means to shift from providing said first feed rate to said second feed rate; and means for comparing the count in said first counter with a predetermined final cutoff value and producing a second output signal when the count in said second counter does not exceed said predetermined final cutoff value, said second output signal being applied to said control means to stop the feeding of material into said container.

Claim 9

Apparatus for batch weighing material fed by a feeder into a container, said feeder having a control means for providing a first and a second feed rate, said first feed rate being greater than said second feed rate, comprising: means for weighing said container, said weighing means producing a digital signal indicative of the weight of the material in said container; means for generating a first pulse train signal having a number of pulses proportional to the difference between a predetermined set point value and the digital signal produced by said weighing means; a first counter for counting the pulses in said first pulse train; means for dividing said first pulse train by a first predetermined number to obtain a second pulse train; a second counter for counting said second pulse train; means for comparing the count in said second counter with a predetermined primary cutoff value and producing a first output signal when the count in said second counter does not exceed said predetermined primary cutoff value, said first output signal being applied to said control means to cause said control means to shift from providing said first feed rate to said second feed rate; and means for comparing the count in said first counter with a predetermined final cutoff value and producing a second output signal when the count in said second counter does not exceed said predetermined final cutoff value, said second output signal being applied to said control means to stop the feeding of material into said container.

Claim 10

Apparatus in accordance with claim 7 wherein said container is a hopper having a control valve at the lower end of said hopper and means for operating said control valve.

Claim 11

Apparatus in accordance with claim 7 wherein said means for weighing said container produces a binary coded decimal digital signal indicative of the weight of the material in said container.

Claim 12

Apparatus in accordance with claim 7 wherein said means for generating the first pulse train signal comprises: a clock for generating a clock signal; a third counter, said third counter being stepped in response to said clock signal; a fourth counter, said fourth counter being stepped in response to said clock signal; first means for detecting coincidence between the count in said third counter and a predetermined set point value; second means for detecting coincidence between the count in said fourth counter and the digital signal produced by said weighing means; and means for gating said clock signal during the period of time between detection of coincidence by said first coincidence detector means and said second coincidence detector means in order to produce said first pulse train signal having a number of pulses proportional to the difference between said predetermined set point value and the digital signal produced by said weighing means.

Claim 13

Apparatus in accordance with claim 10 wherein said clock gating means comprises: a first bistable circuit means, said first bistable circuit means being set in response to the detection of coincidence by said first coincidence detector means and producing an output in response to being set; a second bistable circuit means, said second bistable circuit means being set in response to the detection of coincidence by said second coincidence detector means and producing an output in response to being set; an exclusive OR gate, said exclusive OR gate having a first and a second input and an output, said output of said first bistable circuit means being applied to said first input of said exclusive OR gate and said output of said secoNd bistable circuit means being applied to said second input of said exclusive OR gate to produce an output signal having a duration proportional to the difference between said predetermined set point value and the digital signal produced by said weighing means; and an AND gate having a first and second input and an output, said output signal of said exclusive OR gate being applied to said first input of said AND gate and said clock signal being applied to said second input of said AND gate to produce said first pulse train signal having a number of pulses proportional to the difference between said predetermined set point value and the digital signal produced by said weighing means.

Claim 14

Apparatus in accordance with claim 10 including means for detecting the simultaneous condition of coincidence in said first coincidence detector means and said first pulse train signal, said detecting means producing an output indicating that the weight of the material in said container is in excess of said predetermined set point value.

Claim 15

Apparatus in accordance with claim 7 wherein said dividing means comprises a connection to at least one bit position output of said first counter.

Claim 16

Apparatus in accordance with claim 13 including means to inhibit said first and second outputs in response to said detecting means producing an output.

Claim 17

Apparatus for batch weighing material fed by a feeder into a container, said feeder having a control means for providing a first and a second feed rate, said first feed rate being greater than said second feed rate, comprising: means for weighing said container, said weighing means producing a digital signal indicative of the weight of the material in said container; a first and a second computer module, said first and second computer modules being provided with identical electrical circuits, said electrical circuits including a clock generator, a counter and a coincidence detector on each of said first and second computer modules, means for connecting an output of said clock generator on one of said first and second computer modules to said counters on each of said computer modules, said first computer module coincidence detector detecting coincidence between a count in said counter on said first computer module and a predetermined set point value, said second computer module coincidence detector detecting coincidence between a count in said counter on said second computer module and said digital signal produced by said weighing means, said first computer module producing a first pulse train having a number of pulses proportional to the time difference between detection of coincidence by said coincidence detectors on said first and second computer modules, said second computer module producing a second pulse train having a number of pulses proportional to the count in said counter on said second computer module at the time of detection of coincidence by said coincidence detector on said second computer module; a first and a second detector modules, said first and second detector modules having identical electrical circuits, said electrical circuits including a first and second counter on each detector module, said first and second counters having a smaller capacity than said counters on said computer modules, a first and second coincidence detector on each detector module associated with said first and second counters on each detector module, respectively, said first and second counters on said first detector module and said second counter on said second detector module receiving said first pulse train and being stepped in response thereto, said first and second coincidence detectors on said first detector module and said second coincidence detector on said second detector module detecting predetermined conditions between the count in said counters receiving said first pulse train and predetermined values in order to produce a final cutoff signal, a primary cutoff signal and a cutoff tolerance signal, said first countEr on said second detector module receiving said second pulse train and being counted in response thereto, said first coincidence detector on said second detector module comparing the count in said first counter on said second detector module with a predetermined value to generate a zero tolerance signal output; means responsive to said primary cutoff signal and said final cutoff signal for controlling said control means of said feeder; and means responsive to said cutoff tolerance signal and said zero tolerance signal to indicate whether a tolerance has been exceeded.

Claim 18

Apparatus for batch weighing material fed by a feeder into a container, said feeder having a control means for providing a first and a second feed rate, said first feed rate being greater than said second feed rate, comprising: means for weighing said container, said weighing means producing a digital signal indicative of the weight of the material in said container; a first and a second computer module, said first and second computer modules being provided with identical electrical circuits, said electrical circuits including a clock generator, a counter and a coincidence detector on each of said first and second computer modules, means for connecting an output of said clock generator on one of said first and second computer modules to said counters on each of said computer modules, said first computer module coincidence detector detecting coincidence between a count in said counter on said first computer module and a predetermined set point value, said second computer module coincidence detector detecting coincidence between a count in said counter on said second computer module and said digital signal produced by said weighing means, said first computer module producing a first pulse train having a number of pulses proportional to the time difference between detection of coincidence by said coincidence detectors on said first and second computer modules, said second computer module producing a second pulse train having a number of pulses proportional to the count in said counter on said second computer module at the time of detection of coincidence by said coincidence detector on said second computer module; a first and a second detector modules, said first and second detector modules having identical electrical circuits, said electrical circuits including a first and second counter on each detector module, said first and second counters having a smaller capacity than said counters on said computer modules, a first and second coincidence detector on each detector module associated with said first and second counters on each detector module, respectively, said first and second counters on said first detector module and said second counter on said second detector module receiving said first pulse train and being stepped in response thereto, said first and second coincidence detectors on said first detector module and said second coincidence detector on said second detector module detecting predetermined conditions between the count in said counters receiving said first pulse train and predetermined values in order to produce a final cutoff signal, a primary cutoff signal and a cutoff tolerance signal, said first countEr on said second detector module receiving said second pulse train and being counted in response thereto, said first coincidence detector on said second detector module comparing the count in said first counter on said second detector module with a predetermined value to generate a zero tolerance signal output; means responsive to said primary cutoff signal and said final cutoff signal for controlling said control means of said feeder; and means responsive to said cutoff tolerance signal and said zero tolerance signal to indicate whether a tolerance has been exceeded.