US3455345A - Method of compacting tobacco for curing in hogsheads - Google Patents

Description

July 15, 1969 S. A. PARKER, JR

METHOD OF COMPACTING TOBACCO FOR CURING'IN HOGSHEADS Original Filed June 22, 1964 5 Sheets Sheet 1 EXHAUJT 46 46 0 26.. l 4 I I 47- l m Rl l I JR\\ \3(\ \3 L I 3 \37 l U INVENTOR. Maw/2 49%- MW IfffllP/Vf?! July 15, 1969 s. A. PARKER, JR 3,455,345

METHOD OF COMPACTING TOBACCO FOR CURING IN HOGSHEADS s Sheets-Sheet 2 Original Filed June 22, 1964 Z /M W ,vrraen ys y 15, 1969v s. A. PARKER, JR 3,

METHOD OF COMPACTING TOBACCO FOR CURING IN HOG'SHEADS 3 Sheets-Sheet 5 Original- Filed June 22, 1964 INVENTOR United States Patent 3,455,345 METHOD OF COMPACTING TOBACCO FOR CURING IN HOGSHEADS Samuel A. Parker, Jr., Maysville, Ky., assignor to Parker Tobacco Company, Maysville, Ky., a corporation of Kentucky Continuation of application Ser. No. 376,704, June 22, 1964. This application Jan. 20, 1967, Ser. No. 628,186 Int. Cl. B651) 1/24, 3/18; B30b 15/06 US. Cl. 141-12 4 Claims ABSTRACT OF THE DISCLOSURE This appliction is a continuation of my copending application Ser. No. 376,704, filed June 22, 1964, now abandoned, titled Press for Compacting Tobacco With Improved Density Variation.

This invention relates to a method for compacting materials in particulate flake form, especially tobacco, for curing in hogsheads or containers so that the density of the tobacco is more nearly constant in the vertical direction and gradually diminishes from a maximum at the Wall of the hogshead to a minimum at the center.

In the tobacco industry, after tobacco has been cut in the field, made into hands, and partially cured in the barn, the leaves are threshed or stemmed to remove the mid-rib. After this is done, the leaves are dried to a moisture content of about 12-13%, and are shredded into relatively small flakes, typically no larger than about 11 /2 inches in diameter.

The preparation of tobacco for manufacture into cigarettes necessitates further curing of the shredded material for a period of one or two years at controlled moisture conditions. This is done by compacting the tobacco into hogsheads, which are cylindrical containers usually about four feet in diameter and four feet high, and holding about 900 pounds of tobacco. The threshed, shredded tobacco, which is loose and fluffy, is charged into the hogsheads and compressed perhaps as much as 5 to 8 times in volume, and is stored for a prolonged period during which is mild curing process takes place. Following this, the tobacco, still in the hogsheads, is subjected to a step known as ordering in which the hogsheads are placed in a partially evacuated room and then subjected to steam where by their moisture content is brought to a desired level, prior to actual manufacture into cigarettes.

In the ordering process, it is of the utmost importance that the steam acting on the hogsheads permeate its contents evenly, so that the moisture content of the tobacco will be uniform throughout the hogshead.

Because of the large size of the hogshead and the high density to which the tobacco is packed into it, it is difficult for steam acting upon the outside surface of the hogshead to penetrate effectively all the way into the center of the hogshead or into areas where the density of the tobacco is too high. Very often the density, though proper at the wall, has been too high at the center of the hogshead, and as a result the tobacco at the center of a hogshead has frequently been improperly or inadequately moisturized.

Proper curing and ordering depend on proper com- 3,455,345 Patented July 15, 1969 paction of the tobacco in the hogsheads; that is, they depend upon proper control, throughout the hogshead, of the densities to which the tobacco is packed. By this it is not meant that the density should everywhere be equal, because uniform densification has been found not to establish uniform moisturization.

For many years the conventional process of compacting tobacco into hogsheads has been to charge the loose flulfy tobacco into the hogshead through the open upper end, so that the togacco piles up highest in the center of the hogshead, and then to compact the entire mass with a ram having a flat plate aflixed to its lower end of diameter roughly equal to the internal diameter of the hogshead.

In the conventional compaction process the density of the tobacco in the hogshead is much higher (usually by a factor of several times) at the bottom than at the top, along a given vertical line, and the density of the tobacco is higher at the center than' at the wall. Such density variation is improper for uniform curing and ordering.

Ideally, for best ordering, I have found that the density of the tobacco in the hogshead should be uniform along a given vertical line through the hogshead, i.e., at a constant distance from the center axis, and should be substantially lower along the center axis than adjacent the Wall, and gradually diminish from the wall to the center. Otherwise expressed, the tobacco should not vary in density from bottom to top and should have a soft center. Obviously it is difficult to obtain perfect control of densities in both directions, but this is the optimum condition to be sought after in practice.

A principal object of this invention has been to provide a method of compacting tobacco for improved curing wherein the radial density distribution of the compacted tobacco approaches the optimum conditions, and which at the same time avoids very high compaction at the bottom of the hogshead in relation to the compaction at the top of the hogshead.

Briefly, in a preferred embodiment of this method the hogshead is rotated upon a lower support during filling and tamping. Tobacco is charged into the hogshead from an endless belt which slings the tobacco over the top edge of the hogshead radially against the opposite wall, so that the tobacco piles up deepest against the wall as the hogshead is rotated. The tobacco is compacted by a reciprocable r-am having mounted to it an apertured flat circular plate which is provided with a plurality of apertures. The size of the apertures is 2 /26 inches, and they are spaced so that the ratio of aperture area to tamper area increases toward the center of the tamper.

In the drawings:

FIGURE 1 is an elevation, partly in diagrammatic form, of a tobacco press for carrying out the method of this invention, showing a hogshead in position for filling, the lifting and rotating means, the belt charging means, and means for operating the tamper;

FIGURE 2 is an enlarged section taken on line 22 of FIGURE 3, showing the preferred arrangement of the apertures in the tamper; and

FIGURE 3 is a vertical section through a hogshead in loading position in the press and being charged with tobacco, with the tamper shown in raised position for charging and also shown by dashed lines in a lower position approaching compaction.

In the drawings a tobacco press is shown at 10, and includes a plurality of supports 11, a pressure cylinder 12 supported thereby, a ram 13, and a tamper, tamping head or head plate 14 mounted at the lower end of the ram 13.

A conventional hogshead is shown :at 20 and comprises a wooden or cardboard cylindrical container having an upper edge 21 and a bottom 22. During charging and tarnping it is convenient for the hogshead to be fitted with a cylindrical open ended extension or charger 25 having a lip or flange 26 around its lower edge which fits around the upper edge 21 of the hogshead. Preferably a filling tube 27 comprising an open ended cylinder of equal or slightly smaller diameter than the charger 25 and having a horizontal fiange 28 at its bottom edge is seated,atop the charger 25, and provides a further upward extension of the hogshead. Use of the filling tube 27 and charger 25 enable a greater mass of tobacco to be charged in place for compaction without spilling over.

With reference to FIGURES 1 and 3, the hogshead 20 is shown seated on a wheeled dolly or cart 30, whereby the hogshead may conveniently be moved into position in the press before filling and moved away thereafter. As will be explained, the dolly 30 also acts as means centering the hoghead under the tamper 14 of the press. The hogshead 20 is centered with respect to the dlly 30 within brackets or angles 31 mounted on the dolly. The underside of the dolly is provided with three or morecircularly arranged brackets or centering cams 32, each of which has an inclined or slanting inner edge.

The brackets 32 center the dolly 30 with respect to a lifting piston 35 upon which they are supported and rotated during the compacting operation, and which is aligned with tamper 14.

The lifting piston 35 includes a ram 36 having a cylindrical head or table 37 at its upper end. The diameter of table 37 is about equal to the diameter of the circle circumscribed within the inner ends of the cams 32. When the lower ram 36 is in unextended position, such that table 37 is substantially flush with the surface of the press room floor 3-8, the dolly 30 with the hogshead centered on it may be positioned approximately in position over the table 37, and as ram 36 is then raised, the slanting edges of cams 32 center the dolly on table 37.

Suitable mechanism for operating the lifting piston 35 and revolving table 37 is illustrated in FIG. 1. Ram 36 slides in a cylinder 40 to which suitable hydraulic or pneumatic pressure is applied from a pump P, controlled by a valve V, for selectively raising the table. Ram 36 is rotatable in cylinder 40, and rotational motion is imparted to it by a torque motor 41 which is prevented from rotating itself by a chain or tie back 42.

The function of the lower piston 35 is to support the dolly and hogshead slightly above floor 38 during the filling and compacting operations, while the hogshead is being rotated. As will be explained, rotation of the hogshead during filling distributes the tobacco in such a manner as to provide a soft center when compacted and establishes angularly symmetric density. In operation, when the piston table 37 is elevated as shown, the torque motor 41 is then energized and rotates the table at a rate of approximately 4 to 13 revolutions per minute. As set forth more fully in Patent No. 3,200,859, issued Aug. 17, 1965, to which reference is hereby made, the steady state pressure of the fluid in cylinder 40 may be taken as a measure of the weight of the tobacco in the hogshead.

The apparatus for charging and compacting the loose tobacco in the hogshead is supported above the floor on the tubular support members 11, suitably four in number, spaced around the table 37. Each support member 11 preferably has a short arm 45 pivotally hinged to it, each arm 45 having a wheel 46 mounted at its free end for rotation about a vertical axis, as is best shown in FIG- URE 2. These wheels 46 act as guides or bearings to center the upper end .of the hogshead or charger during rotation. When the hogshead is being positioned or removed from the press, the arms 45 are swung into vertical position by suitable means such as lifting lines 47 connected to their outer ends and passing over pulleys 48. In raised position, the wheels 46 do not block movement of or contact the hogshead or charger, so that the hogshead may be rolled into position within the support members 11.

The upper or tamping cylinder 12 is supported between the members 11 by several brackets 50 which are welded between the respective supports 11 at one end and to the cylinder 12 at the other. The tamping rod or ram 13 is of sufficient length to extend to almost the bottom 22 of the hogshead. The ram may be either hydraulically or pneumatically operated; preferably it is operated by oilless air. Ram 13 can turn with respect to cylinder 12.

FIGURE 1 shows in diagrammatic form a system 49 including a pump P and a double solenoid operated fourway valve for reciprocating the ram 13.

The tamper 14 mounted to the lower end of the ram comprises a generally flat circular plate having an outside diameter somewhat less, preferably about six inches less, than the inside diameter of the hogshead. For use with hogsheads having a diameter of 36-47 inches on the interior, I prefer to use a tamper having a three-inch clearance from the wall of the hogshead, i.e. so that the diameter of the tamper head is about 40 to 41 inches.

As can best be seen in FIGURE 2, the tamper 14 is provided with a plurality of holes or apertures 55 through it, these being spaced so that the distance between the centers of adjacent holes diminishes toward the center of the tamper. That is to say, there are more holes per unit area adjacent the center of the tamper head than adjacent the periphery. The diameter of the holes can be of the order of 2 to 6 inches, but I have found that holes having diameters of about 4 /2 to 5 inches give the best results. The tamper head is made of metal plate of a gauge sufficiently heavy to Withstand bending during compaction. It is preferred that the edges of the holes be rounded to a radius equal to the thickness of the plate. An upwardly extending sheet metal shield 57 is secured around the periphery of tamper 14 to prevent tobacco from accumulating on top of the tamper from around its edge during pressing.

Tobacco is charged into the hogshead from an endless horizontal belt 56, driven by a motor M. The end bearing 57 of the belt 56 is positioned above the upper end of and to the side of the filling tube. Tobacco is deposited onto belt 56 from a central chute 58. The belt speed should be adjusted so that the belt slings the tobacco across the center of the hogshead to the opposite wall, as indicated at 59, so that the tobacco is piled deepest adjacent the wall of the hogshead. Preferably the longitudinal axis of the belt 56 is in line with the center of the hogshead, so that the tobacco is directed radially toward the far wall.

As the tobacco is charged into the hogshead while the latter is being rotated, the tobacco accumulates in the manner illustrated in FIGURE 3, and is higher against the wall of the hogshead or charger or filling tube than at the center. To an extent, the centrifugal force of rotation tends to hold the loose tobacco against the wall of the hogshead, and the build-up in the center is not as great.

It is contemplated that in practice, two similar presses may be arranged side by side, and can both be fed by the belt 56 by reversing the direction of rotation of the motor M. Thus, while tobacco is being charged into the hogshead of one press, the other can be tamped.

In charging a standard 48-inch hogshead, with the belt positioned as shown in the drawings, I have found that a suitable lineal rate of belt travel is about 300 to 450 feet per minute. Lower speeds tend to cause accumulation of the tobacco in the center of the hogshead rather than adjacent the edge, and this in turn tends to undesirably increase the density at the center of the hogshead.

The ram 13 is rotatable with respect to the cylinder 12, so that the head plate 14 can rotate with the hogshead when engaged with the mass of tobacco inside the hogshead during tamping. This permits tamping to be carried out without stopping rotation of the table 37, and improves the density distribution.

During the compacting operation, as shown diagrammatically in FIGURE 3, the head plate 14 first comes into contact with the tobacco adjacent the wall of the hogshead, where it is piled deepest. As the head plate forces the tobacco down, compaction in the center is caused, but the density is higher adjacent the wall than at the center, and changes gradually between the extremes.

The apertures 55 in the head plate 14 have been found effective in tests to equalize density in the vertical direction to a surprising degree. If a flat unapertured head plate is used, in the conventional manner, the density of the tobacco is much higher at the bottom in relation to the density at the top. The high densification resulting when an unapertured head plate is used is believed to be caused by the inability of air in the tobacco to escape as the head plate is brought down, and the pressure on the air and tobacco is greater than if the air could escape. In some cases, the compaction is so great as actually to bulge the hogshead outwardly, and many prior presses operating at high pressures have required support around the bottom of the hogshead to prevent it from bulging outwardly too seriously.

Another important advantage of the apertures in the head plate is to permit compaction to be achieved with fewer tamping strokes at a given ram pressure, than would otherwise be required. This is advantageous, because the difference in density of the tobacco from bottom to top increases with the number of compacting strokes. Since the tobacco at the bottom of the hogshead would be subjected to more compaction strokes than that at the top of the hogshead if an unapertured plate were used, the effect of the apertures, by reducing the number of compaction strokes required, is to reduce the change in density in the vertical direction.

One surprising aspect of the method described is that, even though the tobacco is charged primarily adjacent the wall of the hogshead, after compaction the tobacco lies in generally horizontal strata, that is, it does not dip downwardly toward the center. This condition is generally thought to be advantageous in the industry.

The apertures surprisingly do not cause cutting of the tobacco, and at the same time the tobacco does not bulge up through the holes undesirably. Since the hogshead is rotated between compaction strokes, the holes are usually misaligned with respect to the portions of the tobacco that they previously surrounded, and the surface is more or less fiat after each compaction.

In carrying out the method, the dolly 30 with the hogshead 20 seated on it and a charger 25 and filling tube 27 centered above the hogshead is rolled into position above the lower piston 35. The lower piston is then actuated, and the rollers 36 or guides are dropped into position to keep the hogshead centered as it is rotated.

The ram is reciprocated about 4 or 5 times during the filling of the hogshead for best results. With this tamper it is preferable to tamp as few times as possible, at ram pressures of about 2000-4000 p.s.i. Charging should be discontinued during the actual tamping since the diameter of the holes in the tamper is not great enough for the tobacco to fall through them.

When the hogshead has been filled, the tamper is actuated to apply greater pressure to the tobacco and thereby compress it sufficiently that the header or top cover can be fitted to the hogshead.

I have described the preferred form of my invention, but those skilled in the art will readily comprehend variations and embodiments within the spirit of the following claims.

I claim:

1. In the curing of tobacco, a method of compacting the tobacco in a hogshead to enable more uniform curing therein to take place, said method comprising the steps of,

charging a quantity of tobacco into said hogshead,

while thelatter is rotating about its vertical axis, by directing said tobacco into said hogshead to accumulate more deeply adjacent the wall than in the center thereof,

interrupting the charging of tobacco into said hogshead,

thereafter compacting the tobacco in said hogshead with a rotatable flat tamper plate having a diameter slightly less than that of the hogshead and continuing the rotation of said hogshead during said compacting,

relieving the pressure of air in the tobacco undergoing compaction, through vents in said plate,

and repeating the steps set forth until said hogshead is full of compacted tobacco.

2. The method of claim 1 wherein said pressure is relieved through circular vent holes formed in said tamper plate which are spaced more closely toward the center of said plate than at the edge of said plate.

3. The method of claim 1 wherein said vent holes have diameters larger than the dimension of the tobacco particles.

4. The method of claim 1 wherein said tamper plate is rotated by contact with tobacco in said hogshead while it is exerting pressure thereon.

References Cited UNITED STATES PATENTS 930,787 8/1909 Olson 223 X 2,596,018 5/1952 Fishburne et al. l4l-12 FOREIGN PATENTS 490,973 8/ 1938 Great Britain.

HOUSTON S. BELL, JR., Primary Examiner US. Cl. X.R.

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