Device and method for separating sheet-type products

Abstract

The invention relates to an apparatus and friction singler for singling sheet material, such as bank notes or the like, having a sheet magazine for receiving a stack of sheets, a picking device with a singling cylinder or the like that has one or more friction elements for contacting and conveying the sheets to be singled from the sheet magazine, and a retaining device forming with the singling cylinder a singling gap through which sheets to be singled from the sheet magazine are conveyed successively. To permit reliable singling by the friction wheel singler after long operating times and under different conditions, the retaining force and the feed force on the sheets to be singled are set and/or regulated independently of each other in the area of the singling gap for singling the sheet material.

1 . A friction singler for singling sheet material such as bank notes or the like comprising: 
 a sheet magazine ( 16 ) for receiving a stack of sheets ( 5 ),    a picking device ( 1 ,  1 ′,  4 ,  22 ) with a singling element, such as a singling cylinder ( 1 ,  1 ′) or the like, the singling element having one or more friction elements ( 3 ,  3 ′) for contacting and conveying the sheets ( 5   a ) to be singled from the sheet magazine ( 16 ), and    a retaining device ( 6 ,  14 ,  22 ) forming with the singling element ( 1 ,  1 ′) a singling gap ( 19 ) through which sheets ( 5   a ) to be singled from the sheet magazine ( 16 ) are conveyed successively,    characterized by    an adjusting device ( 9 ,  11 ,  15 ) for setting and/or regulating a retaining force exerted by the retaining device ( 6 ,  14 ,  22 ) on the sheets ( 5   a ) to be singled and a feed force exerted by the picking device ( 1 ,  1 ′,  4 ,  22 ) on the sheets ( 5   a ) to be singled independently of each other in the area of the singling gap ( 19 ) for singling the sheet material.    
     
     
         2 . A friction singler according to  claim 1 , characterized in that the values of the retaining force and the feed force are variable continuously or step-by-step within a range.  
     
     
         3 . A friction singler according to  claim 1  or  2 , characterized in that the retaining device ( 6 ,  14 ,  22 ) has one or more friction areas ( 4 ) for contacting the sheets ( 5   a ) to be singled from the sheet magazine ( 7 ).  
     
     
         4 . A friction singler according to  claim 3 , characterized in that the retaining device ( 6 ,  14 ) has, for contacting the sheets ( 5   a ) to be singled, at least one retaining element ( 6 ,  14 ) opposite the singling element ( 1 ) in the area of the singling gap ( 19 ) such as a retaining wheel ( 14 ) or retaining skid ( 6 ) with the friction areas ( 8 ).  
     
     
         5 . A friction singler according to any of the above claims, characterized in that the picking device ( 1 ,  1 ′,  4 ,  22 ) further comprises a pressure element ( 4 ,  22 ) opposite the singling element ( 1 ) in the area of the singling gap ( 19 ), such as a pressure wheel or pressure skid ( 4 ,  22 ) with one or more sliding areas, the coefficient of friction of the sliding areas being smaller than the coefficient of friction of the friction elements of the singling element ( 1 ,  1 ′).  
     
     
         6 . A friction singler according to claims  3  and  5 , characterized in that the coefficient of friction of the sliding areas is further smaller than the coefficient of friction of the friction areas of the retaining device ( 6 ,  14 ).  
     
     
         7 . A friction singler according to  claim 5  or  6 , characterized in that the distance of the retaining element ( 6 ,  14 ) from the singling element ( 1 ) and the distance of the pressure element ( 4 ,  22 ) from the singling element ( 1 ) are capable of being set and/or regulated independently of each other in the area of the singling gap ( 19 ).  
     
     
         8 . A friction singler according to any of  claims 5  to  7 , characterized in that the adjusting device ( 9 ,  11 ,  15 ) comprises a first fastening device ( 9 ) for fixing the variable position of the retaining element ( 6 ) with respect to the singling element ( 1 ) and/or a second fastening device ( 11 ) for fixing the variable position of the pressure element ( 4 ) with respect to the singling element ( 1 ).  
     
     
         9 . A friction singler according to any of  claims 5  to  8 , characterized in that the adjusting device ( 9 ,  11 ,  15 ) has an adjusting element ( 12 ,  13 ) connected both with the retaining element ( 6 ) and with the pressure element ( 4 ), so that moving the retaining element with respect to the picking device with the aid of the adjusting element simultaneously moves the pressure element and/or moving the pressure element with respect to the picking device with the aid of the adjusting element simultaneously moves the retaining element.  
     
     
         10 . A friction singler according to any of  claims 3  to  9 , characterized in that the friction elements ( 3 ) of the singling element ( 1 ) and the friction areas ( 8 ) of the retaining device ( 6 ) have friction material with a substantially equal coefficient of friction, and the contact area between the friction elements ( 3 ) of the singling element ( 1 ) and a sheet ( 5   a ) to be singled is substantially greater than the contact area between the friction areas ( 8 ) of the retaining device ( 6 ) and the sheet ( 5   a ) to be singled in the area of the singling gap ( 19 ).  
     
     
         11 . A friction singler according to any of the above claims, characterized in that the friction elements ( 3 ) of the singling element ( 1 ,  1 ′) are formed over the full or a limited circumference of the singling element.  
     
     
         12 . A friction singler according to any of the above claims, characterized in that the singling element ( 1 ,  1 ′) has one or more grooves ( 2 ) extending in the conveying direction of the bank notes ( 5   a ) to be singled in the area of the singling gap ( 19 ).  
     
     
         13 . A friction singler according to  claim 12 , characterized in that the retaining device ( 6 ) is formed so that it can engage the grooves ( 2 ) of the singling element ( 1 ,  1 ′) in the area of the singling gap ( 19 ) to set the retaining force.  
     
     
         14 . A friction singler according to  claim 12  or  13 , characterized in that the pressure element ( 4 ,  22 ) is formed so that it can engage the grooves ( 2 ) of the singling element ( 1 ,  1 ′) in the area of the singling gap ( 19 ) to set and/or regulate the feed force.  
     
     
         14 . A friction singler according to claims  13  and  14 , characterized in that the engagement depth of the retaining element ( 6 ,  14 ) and that of the pressure element ( 4 ,  22 ) in the grooves ( 2 ) of the singling element ( 1 ,  1 ′) in the area of the singling gap ( 19 ) are capable of being set and/or regulated independently of each other.  
     
     
         15 . A friction singler according to any of the above claims, characterized in that the retaining device comprises, for contacting the sheets ( 5   a ) to be singled from the sheet magazine ( 16 ), a suction apparatus ( 20 ) with one or more suction openings ( 21 ) for sucking the sheets ( 5   a ) to be singled in the area of the singling gap ( 19 ) by a vacuum.  
     
     
         16 . A friction singler according to  claim 15 , characterized in that the adjusting device sets and/or regulates the vacuum in the area of the suction openings ( 21 ) for setting and/or changing the retaining force.  
     
     
         17 . A friction singler according to  claim 15  or  16 , characterized in that the surface of the suction apparatus ( 20 ) has sliding areas in the areas around the suction openings ( 21 ) that can engage the at least one groove ( 2 ) of the singling element ( 1 ′), the coefficient of friction of the sliding areas being smaller than the coefficient of friction of the friction elements of the singling cylinder ( 1 ′).  
     
     
         18 . A friction singler according to claims  12  and  15 , characterized in that the suction apparatus is formed so that, at least in the area with the suction openings ( 21 ), it can engage the at least one groove ( 2 ) of the singling element ( 1 ′) for setting and/or regulating the feed force.  
     
     
         19 . A friction singler according to  claim 3 , characterized in that the retaining device comprises a retaining roll ( 14 ) with the friction areas ( 8 ), and the adjusting device ( 15 ) is designed so that it can set and/or regulate the rotating speeds of the singling element ( 1 ) and the retaining roll ( 14 ) independently of each other for independently setting feed force and retaining force.  
     
     
         20 . A friction singler according to any of the above claims, characterized by a sensor device to permit at least one physical feature to be measured during the singling process for detecting the singling quality.  
     
     
         21 . A friction singler according to  claim 20 , characterized by a control device connected with the adjusting device for evaluating the measured values of the sensor device after a number of singling processes to detect a need for readjusting the retaining device and/or the picking device to prevent undesirable gaps or multiple picks or the like during ongoing singling.  
     
     
         22 . A friction singler according to  claim 20  or  21 , characterized by a control device connected with the adjusting device for evaluating the measured values of the sensor device during an ongoing singling process to detect a need for readjusting the retaining device and/or the picking device during the ongoing singling process to prevent undesirable gaps or multiple picks or the like during ongoing singling.  
     
     
         23 . A method for singling sheet material, such as bank notes or the like, of a stack of sheets ( 16 ) wherein a singling element, such as a singling cylinder ( 1 ,  1 ′) or the like, having one or more friction elements ( 3 ,  3 ′) contacts a sheet ( 5   a ) to be singled from a stack of sheets ( 16 ) and exerts a feed force thereon to convey the sheets ( 5   a ) successively from the stack of sheets ( 16 ) through a singling gap ( 19 ), a retaining force being exerted by a retaining device ( 6 ,  14 ,  22 ) on the sheets ( 5   a ) to be singled on the side of the singling gap ( 19 ) opposite the singling element ( 1 ,  1 ′) to retain sheets yet to be singled so that only one sheet at a time is singled,  
       characterized in that 
 the retaining force and the feed force on the sheets ( 5   a ) to be singled are set and/or regulated independently of each other in the area of the singling gap ( 19 ) for singling the sheet material.  
 
     
     
         24 . A method according to  claim 23 , characterized in that the values of the retaining force and the feed force are changed continuously or step-by-step within a range.  
     
     
         25 . A method according to  claim 23  or  24 , characterized in that the distance of the retaining element ( 6 ) from the singling element ( 1 ) and the distance of a pressure element ( 4 ) from the singling element ( 1 ) are set and/or regulated independently of each other in the area of the singling gap ( 19 ).  
     
     
         26 . A method according to any of  claims 23  to  25 , characterized in that the retaining force is set and/or regulated by setting and/or varying a vacuum in the area of the singling gap ( 19 ).  
     
     
         27 . A method according to any of  claims 23  to  26 , characterized in that the rotating speeds of the singling element ( 1 ) and a retaining roll ( 14 ) are set and/or regulated independently of each other.  
     
     
         28 . A method according to any of  claims 23  to  27 , characterized in that are detected and evaluated for a number of singling processes to detect a need for readjusting the retaining force and/or feed force to prevent undesirable gaps or multiple picks or the like during ongoing singling [sic].  
     
     
         29 . A method according to any of  claims 23  to  27 , characterized in that measuring data on singling quality are evaluated during an ongoing singling process to detect a need for readjusting the retaining force and/or feed force during the ongoing singling process to prevent undesirable gaps or multiple picks or the like during ongoing singling.