Printer for a cigarette-manufacturing machine

Abstract

A printer for a cigarette-manufacturing machine has a density sensor ( 70 ) disposed between a wrapping section ( 4 ) and a cutting section ( 16 ) of the machine, and the density sensor ( 70 ) detects the print density of printed information (PI) of a tobacco rod (TR). The information (PI) is printed on a paper web W by a printing unit ( 20 ) located upstream from the wrapping section ( 4 ). Disposed between the printing unit ( 20 ) and the wrapping section ( 4 ) is an adjusting device ( 62 ) for varying the length of a feeding path of the paper web W. A density signal from the density sensor ( 70 ) is used to control the operation of the printing unit ( 20 ) and adjusting device ( 62 ). Thus, based on the density signal, the print density of the printed information (PI) and the arrival timing thereof at the density sensor ( 70 ) are each controlled.

1 . A printer for a cigarette-manufacturing machine, said cigarette-manufacturing machine including a wrapping section for receiving a paper web fed along a feeding path at a given speed with filling material, wrapping the filling material in the paper web to form a tobacco rod, and continuously delivering the formed tobacco rod, and a cutting section for cutting the tobacco rod delivered from the wrapping section at a given cut timing and forming cigarette rods of a given length, 
 said printer comprising:    a printing section having a print roller interposed in said feeding path and an ink supply source for supplying ink to said print roller, said printing section for printing given information on the paper web by using said print roller to provide the information to each of said cigarette rods;    a density sensor disposed between the wrapping section and the cutting section, for detecting density of each piece of the printed information on the paper web to output a density signal;    a density-controlling device for controlling print density of the printed information, based on the density signal from said density sensor;    a calculating device for calculating time deviation between an arrival time point at which the printed information provided to the tobacco rod is supposed to arrive at said density sensor and an actual detection time point at which the printed information is actually detected by said density sensor and outputting a calculated deviation; and    a timing-controlling device for controlling arrival timing of the printed information at said density sensor in order to correct the deviation from said calculating device.    
   
   
       2 . The printer according to  claim 1 , wherein: 
 the cigarette rod has a to-be-cut position so as to be cut at the center with respect to a longitudinal direction thereof, and is cut at the to-be-cut position after being fed to a filter cigarette-manufacturing machine to be formed into two cigarettes, and    the printed information includes a pair of marks located at the both side of the to-be cut position of the cigarette rod, respectively.    
   
   
       3 . The printer according to  claim 2 , wherein: 
 said density-controlling device includes:    abnormality-determining means for determining whether the density signal of each cigarette rod falls in a correct range, and outputting a removal signal when the density signal is out of the correct range; and    density-adjusting means for calculating average density of the printed information on the basis of the density signal of a given number of cigarette rods and adjusting an ink supply amount from ink supply means on the basis of the average density calculated.    
   
   
       4 . The printer according to  claim 3 , wherein: 
 said density-controlling device outputs an operation stop signal for the cigarette-manufacturing machine when the average density is at an abnormal level.    
   
   
       5 . The printer according to  claim 3 , wherein: 
 said ink supply means includes an ink spray for spraying ink, and    said density-controlling device varies at least either one of an ink-spray time and an ink-spray interval.    
   
   
       6 . The printer according to  claim 2 , wherein: 
 said timing-controlling device includes:    abnormality-determining means for determining whether the deviation of each cigarette rod falls in a correct range, and outputting a removal signal when the deviation is out of the correct range, and    path length-adjusting means for calculating an average deviation of the printed information on the basis of the deviation of a given number of cigarette rods and adjusting length of said feeding path between the printing section and the wrapping section according to the average deviation calculated.    
   
   
       7 . The printer according to  claim 6 , wherein: 
 said timing-controlling device outputs an operation stop signal for the cigarette-manufacturing machine when the average deviation is at an abnormal level.    
   
   
       8 . The printer according to  claim 6 , wherein: 
 said path length-adjusting device includes:    a guide roller interposed in said feeding path between the printing section and the wrapping section, for guiding travel of the paper web;    a roller carrier for rotatably supporting the guide roller, the roller carrier being displaceable in a direction intersecting said feeding path; and    a drive source for causing the roller carrier to displace.    
   
   
       9 . The printer according to  claim 8 , wherein: 
 the roller carrier is a rotatable arm having the guide roller at a tip end thereof, and a base end of the rotatable arm is rotatably supported.