System and method for discriminating a roll in a paper roll dispenser, and a paper roll

Abstract

The invention comprises a system and a method for discriminating a roll placed in a paper roll dispenser, as well as a paper roll with a core comprising at least one passive element having an electrical conductivity different from that of the core, to be used in conjunction with the dispenser. The system comprises at least two conducting plates located within the paper roll dispenser such that when the roll is positioned within the dispenser, the plates are in proximity of the roll, the plates being electrically insulated from each other, means for detecting capacitance between the plates and generating a signal indicative of said capacitance and means for discriminatng said paper roll based on a value of the signal.

1 . A system for discriminating a roll placed in a paper roll dispenser, comprising: 
 at least two conducting plates located within the paper roll dispenser such that when the roll is positioned within the dispenser, the plates are in proximity of the roll, the plates being electrically insulated from each other; means for detecting capacitance between the plates and generating a signal indicative of said capacitance; and    means for discriminating said paper roll based on a value of the signal.    
     
     
         2 . The system of  claim 1 , wherein the at least two conducting plates are shaped and positioned in an annular fashion in proximity of a roll support structure within the dispenser.  
     
     
         3 . The system of  claim 2 , wherein the means for detecting detects the capacitance between an individual pair of adjacent plates of said plates in a sequenced manner one pair after another such that all combinations of capacitance between adjacent conducting plates are detected.  
     
     
         4 . The system of  claim 1 , wherein the means for detecting comprises: 
 means for applying voltage between two adjacent plates of said plates; means for measuring voltage between two adjacent plates of said plates; control means for controlling said means for applying and means for measuring to scan each pair of said plates by sequentially applying the voltage between the plates of the pair during a given time period, and either measuring the charge or discharge rate of voltage between the plates of the pair to produce said signal.    
     
     
         5 . The system of  claim 4 , wherein the means for applying voltage is an oscillator.  
     
     
         6 . The system of  claim 4 , wherein the means for measuring voltage is integrated in a microprocessor.  
     
     
         7 . The system of  claim 6 , wherein the control means is integrated in the microprocessor.  
     
     
         8 . The system of  claim 1 , wherein the means for discriminating said paper roll comprises comparing means which compares the value of said signal to a reference signal.  
     
     
         9 . The system of  claim 8 , wherein the comparing means is a microprocessor.  
     
     
         10 . The system of  claim 1 , further comprising means for compensating said signal for changes in an environment surrounding the system.  
     
     
         11 . The system of  claim 10 , wherein the means for compensating is integrated in a microprocessor.  
     
     
         12 . The system of  claim 1 , comprising means for detecting a placement of the roll in the system.  
     
     
         13 . The system of  claim 1 , comprising means for informing a user of results of an assessment made by the means for discriminating.  
     
     
         14 . The system of  claim 13 , wherein the means for informing the user comprises a green light and a red light, either one being activated depending on the results of the assessment made by the means for discriminating.  
     
     
         15 . The system of  claim 4 , further comprising means for converting said signal into a continuous voltage.  
     
     
         16 . A method for discriminating a roll placed in a paper roll dispenser comprising the steps of: 
 a) placing the roll in the dispenser;    b) providing at least two conducting plates located within the paper roll dispenser such that when the roll is positioned within the dispenser, the plates are in proximity of the roll, the plates being electrically insulated from each other;    c) detecting capacitance between the plates;    d) generating a signal indicative of said capacitance; and    e) discriminating said paper roll based on a value of the signal    
     
     
         17 . The method of  claim 16  further comprising the steps of: 
 detecting a placement of the roll in the system after step a) and before step c); and    initiating step c) upon detection of the placement of the roll in the system.    
     
     
         18 . The method of  claim 16 , wherein: 
 step b) comprises the step of providing at least two conducting plates shaped and positioned in an annular fashion in proximity of a roll support structure within th dispenser;    step c) comprises the steps of 
 applying voltage between two adjacent plates of said plates; and measuring voltage between two adjacent plates of said plates;  
   step d) comprises the steps of 
 scanning each pair of said plates by sequentially applying the voltage between the plates of the pair during a give time period, and either measuring the charge or discharge rate of voltage between the plates of the pair to produce said signal; and  
 compensating said signal for changes in an environment surrounding the system; and  
   step e) comprises the steps of 
 comparing said signal to a reference signal to obtain an assessment of the signal;  
 converting said assessment signal into a continuous voltage; and  
 informing a user of results based on the continuous voltage.  
   
     
     
         19 . A paper roll comprising a core having at least one passive element having an electrical conductivity different from that of the core.  
     
     
         20 . The paper roll of  claim 19 , wherein the core has a hollow cylindrical shape and comprises at least two strips of material helicoidally rolled around a central axis.  
     
     
         21 . The paper roll of  claim 20 , wherein the at least one passive element is placed at an interface between the at least two strips of material.  
     
     
         22 . The paper roll of  claim 20 , wherein the core comprises more than one passive element and the passive elements are placed symmetrically around the central axis of the roll such that, at any point along the central axis of the roll, there is an equal angular distance with respect to the central axis between passive elements along a circumference of the roll.  
     
     
         23 . The paper roll of  claim 19 , wherein the at least one passive element is a copper wire.  
     
     
         24 . The paper roll of  claim 23 , wherein the copper wire is 36 AWG in size.