Patent Publication Number: US-4056463-A

Title: Tobacco/paper sorter method and apparatus

Description:
This invention relates generally to reclamation of tobacco and more particularly to reclaiming shredded tobacco from cigarettes found to be defective. 
     Defective cigarettes are accumulated and fed to machines, such as shown and described in U.S. Pat. No. 3,665,931, which rip or slit the paper wrappers of rejected cigarettes, with or without filters, and separate the wrappers from the tobacco which is collected from reuse. It has been found that, from the ripping or slitting operation, pieces of paper or paper particles are randomly mixed in the shredded tobacco being reclaimed. Processing the reclaimed tobacco to remove the paper heretofore has been a slow and difficult task which tends to further degrade the shredded tobacco. 
     Accordingly, an object of the present invention is to automatically process reclaimed shredded tobacco from defective cigarettes to remove paper particles therefrom. 
     Another object of the present invention is to process reclaimed shredded tobacco from defective cigarettes to rapidly remove paper particles randomly mixed in the shredded tobacco with a minimum amount of degradation of the tobacco shreds. 
    
    
     The foregoing and other objects and advantages will appear more fully hereinafter from a consideration of the detailed description which follows, taken together with the accompanying drawings wherein one embodiment of the invention is illustrated by way of example. It is to be expressly understood, however, that the drawings are for illustration purposes only and are not to be construed as defining the limits of the invention. 
     FIG. 1 is an elevational view of a machine for separating paper from shredded tobacco in accordance with the present invention. 
     FIG. 2 is an enlarged sectional view of means for separating paper for detection from the shredded tobacco. 
    
    
     The present invention contemplates means generally similar to that in my U.S. Pat. 3,893,563 for detecting and separating paper from the reclaimed shredded tobacco as will be further discussed. 
     Referring now to the drawings, the machine is provided with a base frame 10 and an elongated horizontally disposed endless belt conveyor 11 mounted on a pair of longitudinally spaced rollers 12 and 13, disposed at opposite ends of the frame 10, and driven at a predetermined speed by a motor 14. A hopper 15 for tobacco to be reclaimed is supported by the frame 10 spaced above the input or rear end of the conveyor 11. Because of the tobacco separating action of a cigarette ripper or slitter, metering means such as a vibrating conveyor or an endless belt conveyor 16 with a picker type roller 17, as shown, is provided to feed tobacco from the hopper 15 at a predetermined rate to a throat or chute 18. 
     An accumulator roller 20, driven by motor means 22 and drivingly connected by a gear train 23 to an accelerator roller 21, is disposed at the bottom or lower end of the throat or chute 18 and with the accelerator roller 21 is spaced above the infeed or rear end of conveyor 11. Although, as shown, the motor 14 drives the belt conveyor 11, motor 22 drives rollers 20 and 21, and no motor is shown for driving the belt 16 and roller 17, a single prime mover can be used for driving each, all, or any combination of such tobacco moving means within the scope of the present invention. 
     The accumulator roller 20 is driven at a suitable speed to remove a sufficient amount of tobacco from the chute or throat 18 to fill the accelerator roller 21. The accelerator roller 21, in turn, is driven at a speed suitable for propelling tobacco in a longitudinal flight path above the belt conveyor 11; the flying shredded tobacco and paper particles showering down from the path of flight on to the conveyor 11. It has been found that paper particles resulting from ripping or slitting cigarettes tend to fly or remain air-borne for longer periods of time than the tobacco shreds. Therefore, the flying tobacco will shower down to form a blanket of shredded tobacco on the belt conveyor 11 and the longer flying paper particles will, thereafter, tend to shower down atop the tobacco where they can be readily detected by electro-optical scanning means 26. The belt conveyor 11 is driven at a speed suitable for propelling the shredded tobacco from its delivery end along a path of flight over a baffle plate 31 to receiver means 32, such as a receptacle or a conveyor. 
     It has been found that appropriate separation for detection of paper particles randomly mixed in shredded tobacco can be accomplished with apparatus, for example, having a 16 inch belt conveyor and rollers with the belt conveyor 11 running at 250 ft./min. the accumulator roller 20 running at 160 RPM and the accelerator roller 21 running at 470 RPM. The accumulator roller 20, with a 43/4  inch shell diameter is provided with twenty equally spaced rows of radially extending pins 20P. Each of such rows is provided with 67 pins 20P equally spaced along a 15° helix which extends from one end of the roller 20 to the other. The roller 20 when measured from the outer ends of the pins 20P, has effectively a 51/2 inch diameter. The accelerator roller 21, with a 21/2  inch shell diameter, is provided with twelve equally spaced rows of radially extending pins 21P. Each of such rows is provided with sixty six pins 21P equally spaced along a 15° helix which extends from one end of the roller 21 to the other. The roller 21, when measured from the outer ends of the pins 21P, has effectively a 33/4  inch diameter. To substantially close or reduce the space between adjacent pins 21P, a 5/16 inch blade or rail 21R of sheet material may be connected to each row of pins which extend radially outwardly of the blades or rails and therefore, retain their picker characteristics. The pins 21P pass between the pins 20P and overlap or mesh only to the depth of the blades or rails 21R when such blades or rails are provided. 
     A vertical end frame 25 is connected to the front end of the base frame 10 immediately forward of the delivery end of the endless belt conveyor 11. The end frame 25 mounts inspection means diagrammatically shown comprising a suitable electro-optical array 26 which scans the flow or blanket of shredded tobacco at the delivery end of the conveyor 11, illuminated by light from a source 30, and provides signals to signal processing means 27 when paper particles are detected on the tobacco being scanned. The signal processing means 27, in response to detect signals from the array or scanning means 26, provides appropriately timed signals to a control value means 29 of a pneumatic reject means having pneumatic jets 28 which divert detected paper particles from the normal flight path, after leaving the conveyor 11, to a reject material receiver 33. 
     The reject means 28/29 of the present application may be generally similar to the reject means 64 of my U.S. Pat. No. 3,893,563. The detecting means 26/27/30 merely has to differentiate between the white of the paper particles and the dark tobacco and the belt conveyor 11. Thus, the detecting means of the present application can be much less complicated than the detecting means 60 of my U.S. Pat. No. 3,893,563. 
     Although but a single embodiment of the invention has been illustrated and described in detail, it is to be expressly understood that the invention is not limited thereto. Various changes may also be made in the design and arrangement of the parts without departing from the spirit and scope of the invention as the same will now be understood by those skilled in the art.