US 3077890 A
Description (OCR text may contain errors)
Feb. 19, 1963 F. B. DOYLE Em. 3,077,890
PRODUCTION OF 'I OBACCO PRODUCTS Filed Nov. 22, 1961 2 Sheets-Sheet 1 l '1 l I I STEMS l PRE-CRUSHER H2O ADDED KNIFE MILL WITH SIFTER o 3/8 scREEN 9 45 LEAF MATERIAL NO.B'SBYPRODUCTS BULKING 25 PERIOD T] HI TI /v BLENDING AND RE-DRY TO STEAMING APROXIMATELY I4 RoLL cI-IAMBER |6% 2s 1 I 27 PADDLE-TYPE ---|6 I 28 HEATER I r 22 Two OR MORE PADDLE-TYPE-- 29 LUNGS A.
BEATER I 23 PADDLE-TYPE 3o P 3 BEATER 32 STORAGE ADD MOISTURE As RE UIRED I FOR ROLLING 34 BEGINNINGS 0F RIBBON 'rwo OR MORE ROLLINGS T AFTER STORAGE RIBBON 5 SHREDDING SHAKER RoLLERs SCREEN I I INVENTORS:
H FRANK B. DOYLE I CHASE W.LASSITER FINISHED. JOHN BERNER PRODUCT BY THEIR ATTORNEYS Feb. 19, 1963 F. B. DOYLE ETAL 3,077,890
PRODUCTION OF TOBACCO PRODUCTS Filed Nov. 22, 1961 2 Sheets-Sheet 2 40 l -o.a's 42 4|| l STEMS PREcRusHER BLENDJNG AND L- KNIFE MILL WITH SIFTER S'TEAMING 3/8 SCREEN fCHAMBER I 46 (L STORAGE PADB%IAETEI\YPE 49 GRIND ADD MOISTURE AS RE UIRED FOR ROLLING TWO OR MORE ROLLINGS AFTER STORAGE RIBBON SHREDDING SHAKER ROLLERS SCREEN FINISHED PRODUCT FRANK B. DOYLE CHASE W.LASS|TER JOHN BERNER THEIR ATTORNEYS INVENTORS:
Filed Nov. 22, 1961, Ser. No. 154,267 Claims. (Cl. 131-440) This invention relates to a method for producing strip tobacco in strip or ribbon form from tobacco by-products such as tobacco leaf stems, slivers, leaf material, tobacco dust and the like.
Heretofore, tobacco products made of tobacco byproducts and referred to generally as reconstituted tobacco are made by grinding the tobacco by-products to a finely-divided state and suspending the products in a great excess of water, e.g., 40 to 50 parts of water to one part of tobacco solids by weight. The suspension is discharged onto a paper-making screen where a sheet is formed by removal of water and the sheet is dried with heat to self-sustaining form. Inasmuch as a large amount of water is used in the process and its removal is expensive, the process is uneconomical.
In another method, finely-divided tobacco particles are bonded together by means of a large proportion of a binder such as carboxymethyl cellulose, vegetable gum and the like in an amount up to 10% or more. Inasmuch as binders are expensive and when burned contribute to an unpleasant aroma and taste, the resulting products are not very satisfactory. Moreover, the binder renders the product dark in color and relatively stiff and brittle and gives it a relatively high density factor and a lower bulking and filling power than the cut leaf tobacco used in cigarettes.
In accordance with the present invention, a process has been provided whereby tobacco by-products can be converted, without the addition of binders, and in the presence of a relatively low amount of water or moisture, into a self-sustaining strip or ribbon which can be readily shredded and in which the shreds are capable of withstanding handling during the manufacture of cigarettes therefrom. Moreover, a product of satisfactory taste, aroma and color can be produced in an expeditious and economical manner. 7
More particularly, in accordance with the present invention, a strip or ribbon is made of tobacco by-products such as stems, slivers, leaf fragments such as No. 8s (8 mesh per inch screen size) and the like, by repeatedly rolling moist particles of tobacco by-products and breaking up the rolled material until the particles adhere and form a continuous strip or ribbon of the desired strength. While the phenomenon involved is not clearly understood, it appears that the repeated rolling, tearing and re-rolling of the tobacco fragments releases binder materials which are naturally present in the cells of these products so that the natural binder acts to unite the ribbon fragments into a self-sustaining strip. The operation can be continuous, enabling a strip of tobacco to be produced Without the need for additional binders, without the use of large quantities of water and at a high production rate.
For a better understanding of the present invention, reference may be had to the accompanying drawings in which:
FIGURE 1 is a schematic flow sheet illustrating one method of practicing the invention;
FIGURE 2 is a schematic flow sheet illustrating a modified method of practicing the invention; and
FIGURE 3 is a perspective view of a portion of a paddle-type beater used in the processes disclosed in FIG- URES 1 and 2.
Referring to FIGURE 1, tobacco leaf stems in the 3,077,890 Patented Feb. 19, 1963 form in which they are normally recovered as a byproduct, e.g., in pieces from a quarter to several inches long, are introduced into a mill 10 provided with a inch screen. The material is broken or cut in the mill into particles of a size such as to pass through the 43 inch mesh screen. These particles are delivered to a sifter 11 where the more finely-divided particles, sand, grit and the like are separated from the tobacco stem particles. The sifted and cleaned product is then delivered to a tank 12 where water is added to the product. Thereafter, the wet stern products are supplied to a larger tank 13 where they are soaked for several hours until they become thoroughly moistened and their water content is increased to between about 9% and 45% by weight.
After soaking, the wet material is passed between a pair of squeeze rolls 14 and 15 where it is flattened and compressed. The flattened but still fragmentary material in a rudimentary strip form is discharged into a paddle-type beater 16. As shown in FIGURE 3, the beater 16 has a generally cylindrical shell 17 provided with an inlet 18 and an outlet 19. Rotatably mounted within the shell 17 is a square shaft 20 on which a series of inclined paddles 21 are mounted. A motor (not shown) rotates the shaft 20 and so that the paddles 21 break up the material into fragments which are discharged through the outlet 19. The fragments from the beater 16 are then passed between one or more pairs of squeeze rolls 22 and 23 where they are again converted into a rudimentary strip of flattened disconnected fragments which is again broken up in another paddle-type beater 24 like the beater 16.
The fragments discharged from the beater 24 are delivered to a drying chamber 25 where they are dried to a moisture content of approximately 16% by weight. The moisture content is not critical and can be between 10 and 20% by weight. Following drying, the material is supplied to a blending and steaming chamber 26 where it is mixed with leaf material such as No. 8s, (leaf tobacco particles capable of passing through an 8 mesh screen) and other tobacco by-products and the moisture content of the mixture is readjusted to between 10% and 20% if necessary. The mixture of tobacco particles and fragments is again passed between squeeze rolls 27 and 28 where it is converted into a relatively weak strip. As the fragments are passed through successive squeeze rolls, they become progressively more adherent and the rudimentary strip formed therefrom becomes more formretaining. However, the strip discharged from the squeeze rolls 27 and 28 is not self-sustaining and it must be subjected to further treatment as, for example, in another paddle-type beater 29 and further rolling between the rolls 3t and 31.
The material discharged from the rolls 3% is delivered to a storage compartment or chamber 32 from which it may be withdrawn as required. Material in the storage chamber 32 now is attaining the ability to be formed into a self-sustaining strip. The material which is in the form of flakes of relatively large size, is ground in a knife mill 33 to a fine particle size (about 20 to 60) and if the moisture content has dropped much below 16%, moisture may be added. This material is then discharged to another pair of rolls 34 and 35 which are of relatively small diameter, e.g., 2 to 3 inches in diameter and having a peripheral speed of about 225 to 325 feet per minute. Material issuing from the rolls 34 and 35 is in the form of a continuous thin ribbon or strip. However, it is still weak and will not withstand the handling to which it is subjected in the manufacture of cigarettes, for example. Accordingly, the material is again reground into flakes in a knife mill 36 to a particle size of-about 20 to 60 mesh and is subjected to two or more additional rollings between rolls 37 and 38 which convert the ground product into a strong self-sustaining ribbon.
two and five-eighths inches in diameter, a size which has been found to be capable of producing a strip or ribbon of the desired strength. The ribbon may be passed between a pair of shredding rolls 39 and cut into shreds of suitable dimensions for further use.
Any fragments of tobacco which may be formed during the shredding operation are discharged to a s aker screen 41 which separates them for return to the mill 36.
The procedural steps set forth above are SlJbJEC'L to considerable modification. Thus, for example, the tep of redrying to a controlled moisture content in the redrying chamber may be omitted and the material passed directly from the beater 24 to the blending and steaming chamber 26. Likewise, the paddle-type beater 29 and the rolls 30 and 31 may be omitted, if des1red. Further, additional rollings may be included following grinding in the mill 36, if additional strength is required.
Another modification of the process is shown in FIG- URE 2 of the drawing. In this operation, the stems are supplied to a knife mill and after being divided to a We inch size and sifted in the sifter 41', are blended with the other tobacco leaf products such as No. 8s (8 mesh per inch screen size), tobacco dust and the like in the blending and steaming chamber 42. Thereafter, the material is rolled between rolls 43 and 44 and is supplied to a paddle-type beater 45 where the material is broken into small fragments. The fragments are rolled between the rolls 46 and 47 and delivered to a storage chamber 48 to be used as required. Subsequent processing includes grinding in the grinder 49, adjusting the moisture content of the ground material to between about 10% and 20% by weight, rolling between rolls 50 and 51, regrinding and then subjecting to additional rollings and shredding. In either case, the product of the operation yields a tough durable strip and the shreds produced from the ribbon are self-sustaining and of physical characteristics which lend them to ready blending with other tobacco materials. During the entire processing, no binders are added, although, if desired, fiavorings, humectants and the like may be added with water at any of the stages of the process where the water is added.
The moisture content of the material is not critical except in the final ribbonforming stage. However, the higher percentage of moisture added in the earlier stages of processing seems to facilitate the formation of a satisfactory ribbon.
Roll spacing, likewise, is not critical although closer spacing of the rolls, particularly in the early stages of the process, has a tendency to produce a tougher final product. The spacing between the rolls in the final stages should, however, be such as to produce a strip or ribbon having about the thickness of natural leaf tobacco. A gap or spacing between the rolls 37 and 38 of between about .003 and .02 inch has proved to be satisfactory.
Rolls of relatively small diameter, i.e., about two and five-eighths inches produce the best results in the final rolling of the material to form the finished ribbon. Evidently, the angle of approach of the surfaces at the nip of such small rolls aids in combining the particles by releasing and activating the natural binders of the tobacco particles to bond them together. Also, passing the fragments of the rudimentary strip between sets of rolls of progressively smaller sizes, especially in the later rolling stages of the process, results in quicker processing of the material.
From the preceding description of typical processes embodying the present invention, it will be understood that the process i primarily one of repeatedly rolling and disintegrating the tobacco products until the material is converted into a state in which the natural binders or other natural components of the tobacco bond the particles together.
The sequence of operations is susceptible to variation as indicated above and, accordingly, the processes de- The rolls 3'! and 33 are 4i scribed herein should be considered as illustrative and not as limiting the scope of the following claims.
1. A method of producing tobacco products from tobacco by-products, which comprises macerating said byproducts, moistening the macerated by-products with water, rolling the saturated by-products into a rudimentary strip, subdividing said rudimentary strip into fragments, rolling the said fragments into a second rudimentary strip, subdividing said second rudimentary strip into fragments, partially drying said last-named fragments, mixing said last-named fragments with finely-divided tobacco, and rolling said mixture into a self-sustaining strip.
2. A method of producing tobacco products from tobacco by-products, which comprises macerating said byproducts, mixing the macerated by-products with water, storing said mixture of tobacco and water for a predetermined waiting time suflicient to cause the tobacco to become thoroughly moistened and increase its volume, rolling the saturated tobacco into a rudimentary strip, subdividing said rudimentary strip into fragments, forming the said fragments into a second rudimentary strip, subdividing said second rudimentary strip into fragments, partially drying said last-named fragments, mixing said lastnamed fragments with finely-divided tobacco, and rolling said mixture into a self-sustaining strip.
3. A method of producing tobacco products from tobacco by-products, which comprises macerating said by-products, moistening the macerated by-products with water in an amount between 9 and 45 of the weight of the by-products, rolling the wet lay-products into a rudimentary strip, subdividing said rudimentary strip into fragments, forming the said fragments into a second rudimentary strip, subdividing said second rudimentary strip into fragments, and compacting said fragments between rolls about two and five-eighths inches in diameter into a self-sustaining strip.
4. A method of producing tobacco products from tobacco lay-products, which comprises macerating said by-products, wetting the macerated by-products with Water in an amount between 9 and 45 of the weight of the by-products, rolling the wet byproducts into a rudimentary strip, subdividing said rudimentary strip into fragments, and rolling the said fragments into other rudimentary strips, and repeatedly subdividing said strips into fragments and rolling said fragments between rolls of progressively smaller diameters until a self-sustaining strip is forced.
5. A method of producing tobacco products from tobacco try-products, which comprises macerating said byproducts, miXing the macerated tobacco with water, storing said mixture of by-products and water for a predetermined waiting time sufficient to cause the by-products to become thoroughly moistened, rolling the moistened byproducts into a rudimentary strip, subdividing said rudimentary strip into fragments, and repeatedly and alternately rolling the said fragments into other rudimentary strips and subdividing said other strips into fragments, partially drying said last-named fragments, and rolling said fragments between rolls having a diameter of about two and five-eighths inches to form them into a self-sustaining strip.
6. The method set forth in claim 5 in which said lastnamed fragments are partially dried to a moisture content between 10 and 20% by weight.
7. The method set forth in claim 5 in which said macerated byproducts are moistened with water in an amount between 9 and 45% by weight and said lastnamcd fragments are partially dried to a moisture content between 10 and 20% by weight.
8. A method of producing tobacco products from tobacco by-products, which comprises macerating the tobacco lay-products, wetting the macerated tobacco with water to increase the moisture content of the 'by-products in an amount between 9 and 45% by weight, rolling the Wet by-products into a rudimentary strip, subdividing said rudimentary strip into fragments, repeatedly and alternately rolling the said fragments into other rudimentary strips and subdividing said other strips into fragments, partially drying said last-named fragments to a moisture content between 10 and 20% by weight and rolling said mixture between rolls about two and five-eighths inches in diameter to form said partially dried fragments into a self-sustaining strip.
9. The method set forth in claim 8 in which said partially dried fragments are mixed with a finely-divided tobacco by-product prior to rolling to form a self-sustaining sheet.
10. A method of producing tobacco products from tobacco by-products forming a mixture of fragments of tobacco by-products, repeatedly rolling said mixture to produce a rudimentary sheet, subdividing said sheet into fragments, adjusting the moisture content of said fragments to between 10% and by weight, subdividing the fragments into particles having a size of about 20 to mesh and finally rolling the particles between rolls of about two and five-eighths inches in diameter to form a self-sustaining ribbon.
References Cited in the file of this patent UNITED STATES PATENTS 236,510 Pacholder Jan. 11, 1881 1,968,403 Kinker July 31, 1934 FOREIGN PATENTS 643,749 Germany May 4, 1937 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3,077,890 I February 19, 1963 Frank B. Doyle et al.
It is hereby certified that error appears in the above numbered patent requiring correction and that the said Letters Patent should read as corrected below.
Column 6 line l6 number of the German Patent, for "643, 749" read 643,794
Signed and sealed this 7th day of May 1963.
DAVID L. LADD Commissioner of Patents ERNEST W. SWIDER Attesting Officer