Automatic feeder control system to account for input variations

Abstract

The present application relates generally to a method and system for the processing of mail items within a document processing system. More specifically, described herein is a method and system for automatically adjusting the feeding of mail items based on a stack pressure for minimizing jams and improving the overall system efficiency. Stack pressure is monitored as mail items are fed to a transport path and mail item feeding behavior is adjusted according to the stack pressure to minimize the mail item jams.

1 . A method for adjusting a mail feeding system, the method comprising steps of:
 advancing a plurality of mail items in a first direction toward a guide mechanism, the guide mechanism configured to guide the plurality of mail items to a transport path, wherein the guide mechanism has a variable angular displacement indicative of a stack pressure against the guide mechanism;   comparing the variable angular displacement of the guide mechanism with a pre-determined angular displacement; and   adjusting the stack pressure in response to the comparing step by advancing one or more of the plurality of mail items in a second direction opposite to the first direction.   
     
     
         2 . The method of  claim 1 , wherein the adjusting step is performed during active operation of the transport path. 
     
     
         3 . The method of  claim 1 , further comprising the steps of:
 determining whether the variable angular displacement of the guide mechanism is greater or equal to the pre-determined angular displacement;   generating a first control signal in response to a result of the determination; and   adjusting the stack pressure in response to the first control signal.   
     
     
         4 . The method of  claim 1  further comprising the step of:
 continuously monitoring the variable angular displacement of the guide mechanism by utilizing a position sensor; and   continuously monitoring the presence of mail items proximate to the guide mechanism by utilizing a presence sensor.   
     
     
         5 . The method of  claim 3 , wherein the guide mechanism has one or more belts driven by a guide motor and the one or more belts drive the plurality of mail items to the transport path. 
     
     
         6 . The method of  claim 5 , further comprising:
 deactivating the guide motor in response to the first control signal.   
     
     
         7 . The method of  claim 5 , further comprising:
 increasing a rotational speed of the guide motor in response to the first control signal and the presence of mail items proximate to the guide mechanism.   
     
     
         8 . The method of  claim 3 , further comprising:
 advancing one or more of the plurality of the mail items in a second direction opposite to the first direction in response to the first control signal.   
     
     
         9 . The method of  claim 3 , further comprising:
 reducing a speed for advancing the plurality of mail items in the first direction in response to the first control signal.   
     
     
         10 . A method for guiding a plurality of mail items to a transport path from a magazine of a document processing device, the method comprising steps of:
 advancing a first mail item and a second mail item in a first direction towards a guide mechanism, the guide mechanism configured to guide the first and the second mail items to a transport path;   monitoring, prior to entry to the transport path, a distance between the first mail item and the second mail item;   adjusting the guide mechanism from a first to a second feed rate in response to the distance between the first mail item and the second mail item and profile data associated with the first and second mail item; and   feeding the second mail item at the second feed rate onto the transport path based on the adjusting step.   
     
     
         11 . The method of  claim 10 , wherein the profile data includes one or more of: a magazine belt speed profile, stack pressure sensor thresholds, gripper belt speed profile, sensor status, gap or pitch threshold and job characteristic data. 
     
     
         12 . The method of  claim 10 , wherein the distance represents a gap length or a pitch. 
     
     
         13 . The method of  claim 10 , wherein the monitoring step further comprises:
 detecting a first edge of the first mail item and a second edge of the second mail item; and   calculating pitch as the time duration between the first edge of the first mail item and the second edge of the second mail item.   
     
     
         14 . The method of  claim 10 , wherein the monitoring step further comprises:
 detecting a second edge of the first mail item and a first edge of the second mail item; and   calculating the gap as the time duration between the first edge of the first mail item and the second edge of the second mail item.   
     
     
         15 . The method of  claim 10 , wherein the guide mechanism includes a motor and one or more belts driven by the motor and wherein the one or more belts drive the first and the second mail items to the transport path. 
     
     
         16 . The method of  claim 10 , wherein the step of adjusting further comprises:
 detecting a subsequent mail item proximate to the guide mechanism; and   adjusting a rotational speed of the belt motor.   
     
     
         17 . The method of  claim 10 , wherein the step of adjusting further comprises:
 comparing the calculated pitch to a specified minimum pitch threshold;   determining a difference between the specified minimum pitch threshold and the calculated pitch; and   adjusting the guide mechanism from a first feed rate to a second feed rate respective to the determined difference in order to meet the specified minimum pitch threshold.   
     
     
         18 . A feeder system comprising:
 a variable speed magazine for driving a plurality of mail items in a direction toward or away from a transport path of a sorter;   a guide mechanism for guiding each of the plurality of mail items onto the transport path;   one or more guide mechanism sensors for continuously measuring a variable angular displacement indicative of a stack pressure against the guide mechanism;   one or more gripper belts associated with the guide mechanism capable of being driven in at least two speeds, the gripper belts suitably contacting at least one of the plurality of mail items as it is driven by the magazine;   one or more sensors for monitoring a distance between successive mail items fed onto the transport path by said guide mechanism; and   a feeder control system for maintaining a consistent rate at which mail items are guided from the magazine onto the transport path by the guide mechanism,   wherein response to an indicated stack pressure the feeder control system drives the magazine in the direction toward or away from the transport path; and   wherein response to the monitored distance the feeder control system adjusts the speed of the gripper belts.   
     
     
         19 . The system of  claim 18 , wherein the feeder system responds to profile data including one or more of: magazine belt speed profile, stack pressure sensor thresholds, gripper belt speed profile, sensor status, gap or pitch threshold and job characteristic data. 
     
     
         20 . The system of  claim 19 , wherein the profile data may vary by client or job to be processed by the sorter. 
     
     
         21 . The system of  claim 18 , wherein the monitored distance represents a gap length or pitch between successive mail items. 
     
     
         22 . The method of  claim 18 , wherein the guide mechanism includes a guide motor for driving the one or more belts, said guide motor activated responsive to the presence of at least one of the plurality of mail items proximate to the guide mechanism. 
     
     
         23 . The method of  claim 22 , wherein the guide motor increases a speed of the gripper belts. 
     
     
         24 . The method of  claim 22 , wherein the guide motor decreases a speed of the gripper belts.