Method of and machine for gathering paper sheets and the like

• US 4,966,354 A
• Filed: 05/22/1989
• Issued: 10/30/1990
• Est. Priority Date: 12/18/1986
• Status: Expired due to Term

• Current Assignee: Grapha-Holding Ag (Rudolf B Mueller)
• Original Assignee: Grapha-Holding Ag (Rudolf B Mueller)
• Inventors: Grunder, Roland
• Primary Examiner(s): Look, Edward J.
• Assistant Examiner(s): NEWHOLM, THERESE
• Application Number:
  US07/356,584
• Time in Patent Office: 526 Days
• Field of Search: 270/54-59, 271/262, 271/263
• US Class Current: 270/56
• CPC Class Codes: B65H 2511/529 number thereof, frequency of occurrence
• CPC Class Codes: B65H 39/055 by collecting in juxtaposed carriers
• CPC Class Codes: B65H 43/04 detecting, or responding to, presence of faulty articles B65H43/08 takes precedence; diverting faulty articles from main streams B65H29/62

Abstract

The thickness of successive sheets which are delivered by the feeders of a gathering machine to a collating conveyor are monitored and a computer which is associated with each feeder calculates the extent of deviation of the monitored thickness from an acceptable value. Signals which are generated by the computers in the event of excessive deviation are used to arrest the motor of the gathering machine and/or to expel the respective groups of sheets from the collating conveyor. Each computer is caused to calculate a reference value on the basis of monitored thicknesses of n successively delivered sheets whose thicknesses are within the acceptable range.

Claims

1. A method of manipulating sheets in a gathering machine wherein at least one feeder supplies successive sheets at predetermined intervals into a predetermined path along which the sheets are transported and wherein the sheets are accumulated into stacks or analogous formations, comprising the steps of monitoring the thickness of successive first sheets on their way toward said path;

counting the number of successive monitoring steps;

calculating a range of acceptable thicknesses based on the last one of a preselected number of successive at least approximately identical first sheet thicknesses, said calculating step being performed in such a manner that the middle of said range is a function of said last monitored first sheet thickness;

monitoring the thicknesses of successive second sheets on their way toward said path;

comparing the monitored second sheet thicknesses with said range and generating signals denoting the relationship of each monitored second sheet thickness to said range; and

expelling said second sheets from said path in response to said signals when monitored second sheet thickness is outside of said range.

2. The method of claim 1, further comprising the steps of counting the number of successive monitoring steps following said calculations step, and employing the last one of a predetermined number of successive at least approximately identical monitored thicknesses following said calculating step to update said range.

3. The method of claim 2, wherein the employing step is repeated regularly.

4. The method of claim 1, further comprising the step of arresting the machine when the monitored thickness of a given number of successive second sheets is outside of said range.

5. The method of claim 4, wherein said given number is three.

6. The method of claim 1, wherein a plurality of feeders supply successive sheets into said path and said steps are performed for the sheets from each of said feeders.

7. The method of claim 1, further comprising the steps of establishing another range of acceptable thicknesses such that the middle of said other range is the monitored thickness of a foremost single one of said first sheets, comparing the monitored thicknesses of the remainder of said first sheets with said other range and generating additional signals denoting the relationship of each such thickness to said other range, and expelling said first sheets from said path in response to said additional signals when monitored first sheet thickness is outside of said other range.

8. The method of claim 7, wherein the steps of monitoring the thicknesses of successive first sheets, counting the number of monitoring steps, establishing said other range, comparing monitored first sheet thickness with said other range and generating additional signals are repeated whenever first sheets are expelled from said path before said preselected number of successive at least approximately identical monitored first sheet thicknesses is obtained.

9. A machine for gathering sheets into stacks or analogous accumulations, comprising a collating conveyor defining a predetermined path for accumulations of sheets, a plurality of feeders each of which is arranged to deliver a discrete series of sheets into the path, means for monitoring the thicknesses of sheets which are supplied by the feeders and for generating first signals denoting the monitored thicknesses, and means for processing said signals including means for evaluating the signals denoting the monitored thicknesses and for calculating an acceptable range of signals on the basis of the last signal of n successive at least approximately identical first signals, said processing means being programmed to calculate said range in such a manner that the middle of said range is said last signal.

10. The machine of claim 9, wherein said monitoring means is designed to generate second signals following calculation of said range and denoting monitored sheet thicknesses, said processing means including means for updating said range on the basis of the last one of a preselected number of successive at least approximately identical second signals.

11. The machine of claim 10, wherein said processing means is designed to repeatedly and regularly update said range.

12. The machine of claim 9, further comprising means for arresting said conveyor in response to detection of a given number of successive first signals outside of the respective range.

13. The machine of claim 12, wherein said given number is three.

14. The machine of claim 9, wherein said monitoring means is designed to generate second signals following calculation of said range and denoting monitored sheet thicknesses, said processing means being designed to compare said second signals with said range and to generate third signals denoting the relationship of each second signal to said range;

and further comprising means for expelling sheets from said path in response to said third signals when a second signal is outside of said range.

15. The machine of claim 14, wherein said first signals denote the monitored thicknesses of a group of first sheets and said second signals denote the monitored thicknesses of a group of second sheets, said processing means being designed to establish another acceptable range of signals such that the middle of said other range corresponds to a first signal denoting the monitored thickness of a foremost single first sheet, and said processing means further being designed to compare the remaining first signals with said other range and to generate additional signals denoting the relationship of each remains first signal to said other range, said expelling means being arranged to expel first sheets from said path in response to said additional signals when a remaining first signal is outside of said other range.

16. The machine of claim 15, wherein said processing means is designed to reestablish an acceptable range corresponding to said other range, to compare first signals with the reestablished range and to generate additional signals in automatic response to expulsion of first sheets from said path before n successive at least approximately identical first signals are obtained.

17. A method of manipulating sheets in a gathering machine wherein at least one feeder supplies successive sheets at predetermined intervals into a predetermined path along which the sheets are transported and wherein the sheets are accumulated into stacks or analogous formations, comprising the steps of monitoring the thicknesses of successive sheets on their way toward said predetermined path by scanning, at said intervals, a second path wherein the sheets advance toward said predetermined path;

counting the number of successive monitoring steps;

utilizing the last one of a preselected number of successive at least substantially identical monitored thicknesses to select a range of acceptable thicknesses;

comparing the monitored thicknesses of successive sheets with a reference value and generating signals denoting the deviation of each monitored thickness from the reference value;

expelling the sheets from said predetermined path in response to said signals when the deviation of the monitored thickness from the reference value is outside of said range;

monitoring said second path in the absence of a sheet therein to thus establish a calibrating thickness;

comparing the monitored thickness of the foremost sheet of said successive sheets with said calibrating thickness; and

selecting a range of acceptable thicknesses as a function of the difference between the monitored thickness of the foremost sheet and the calibrating thickness.

18. A method of manipulating sheets in a gathering machine wherein several feeders supply successive sheets at predetermined intervals into a predetermined path along which the sheets are transported and wherein the sheets are accumulated into stacks or analogous formations, comprising the steps of monitoring the thicknesses of successive sheets on their way toward said path;

counting the number of successive monitoring steps;

utilizing the last one of a preselected number of successive at least substantially identical monitored thicknesses to select a range of acceptable thicknesses;

expelling from said path the sheets which are supplied by the feeders until after completion of selection of such range for successive sheets from each of the feeders;

comparing the monitored thicknesses of successive sheets with a reference value and generating signals denoting the deviation of each monitored thickness from the reference value; and

expelling the sheets from said path in response to said signals when the deviation of the monitored thickness from the reference value is outside of a range of acceptable thicknesses.

19. A machine for gathering sheets into stacks or analogous accumulations, comprising a collating conveyor defining a predetermined path for accumulations of sheets;

a plurality of feeders each of which is arranged to deliver a discrete series of sheets into the path;

respective means for monitoring the thicknesses of sheets which are supplied by the feeders and for generating first signals denoting the monitored thicknesses; and

respective means for processing said signals and each including means for evaluating the signals denoting the monitored thicknesses and for calculating a range of acceptable deviations of signal from a reference signal on the basis of the last signal of n successive substantially identical first signals, means for preventing the delivery of the foremost sheet by the respective feeder so that the respective monitoring means then generates a first signal which is indicative of a sheet having zero thickness and constitutes a calibrating signal, and means for comparing the first signal denoting the thickness of the foremost delivered sheet with the respective calibrating signal to thereby ascertain a range of acceptable deviations of signals from a reference signal as a function of the difference between the signal denoting the thickness of the foremost delivered sheet and the calibrating signal.

20. A machine for gathering sheets into stacks or analogous accumulations, comprising a collating conveyor defining a predetermined path for accumulations of sheets;

a plurality of feeders each of which is arranged to deliver a discrete series of sheets into the path;

means for monitoring the thicknesses of sheets which are supplied by the feeders and for generating first signals denoting the monitored thicknesses;

means for processing said signals including means for evaluating the signals denoting the monitored thicknesses and for calculating a range of acceptable deviations of signals from a reference signal on the basis of the last signal of n successive substantially identical first signals; and

means for expelling sheets from said path prior to completion of calculation of said range for each of said feeders.