US3326220A - Pressing and packing machine for packing tobacco in portion packets - Google Patents

Description

June 20, 1967 Q v 3,326,220

PRESSING AND PACKING MACHINE FOR PACKING TOBACCO IN PORTION PACKETS Filed Aug. 27, 1964 FIGQI INVENTOR ATTORNEY$ United States Patent 4,51 2 Claims. (Cl. 131-111) This invention relates to pressing and packing machines for packing tobacco in portion packets, comprising means for intermittently supplying measured portions of tobacco to a pressing chamber in which each portion is compressed by means of a ram prior to the transfer of said portion to a package envelope.

When tobacco, especially pipe tobacco, is packed in retail packets, it is common procedure to subject a measured quantity of tobacco to a pressing operation in order to form it into a desired shape dependent on the type of package used. During its previous manufacture, the tobacco has normally been subjected to a so-called casing or saucing treatment, which involves that different aromatic or sweetening substances, such as licorice, molasses and extracts of prunes, etc., have been added. As a result of such treatment the tobacco has become more or less sticky and it will, therefore, during said pressing operation have a tendency to stick to the surfaces with which it gets into contact. It has been attempted to overcome this disadvantage by wrapping the quantity of tobacco, before the pressing operation, into a fluid-tight cover which thus forms part of the finished package. However, such a cover represents a superfluous and, consequently, cost-increasing element when the outer package envelope, as is now usual, is made of a substantially fluidand air-tight material, such as for example a polyethylene pouch or bag.

It has been proposed to line the walls of the pressing chamber and the press ram with felt and to coat said felt with parafiin wax in order to create a smooth surface. However, this solution has turned out to be insufiicient for preventing a layer of casing substances and tobacco parts from successively accumulating on and sticking to the said surfaces of the pressing chamber during operation of the machine, and it has therefore in practice been necessary to stop the packing machine and clean said surfaces at relatively short intervals, about every second hour. It has also been suggested to heat the walls of the pressing chamber in order to render the casing substances more fluid so as to permit them of running down the walls instead of sticking thereto. However, in this case it is also necessary to discontinue operation and clean the pressing chamber at intervals. Moreover, the heating of the pressing chamber involves the risk of scorching the tobacco, and said method is also disadvantageous in connection with the packing of tobacco in envelopes of polyethylene which already softens at a temperature of about 80 C.

The disadvantages as above indicated are obviated by the present invention which consists in that the machine is provided with means adapted to cool, during operation of the machine, such walls of the pressing chamber and the ram that during the pressing operation get into contact with the tobacco.

This simple measure has turned out to be fully sufiicient for preventing the deposition of sticky casing substances and adhering tobacco parts on the surfaces of the pressing chamber and of the ram, provided that the cooling of said walls is carried so far that the air adjacent said walls is cooled below its dew point whereby its moisture content will condense on the walls and operate as a thin lubricating film thereon. Practical experiences show that it is possible in this way to avoid the above-mentioned deposits on the walls of the chamber and the ram, even after very prolonged operation.

According to a feature of the invention, the walls may be hollow and provided with inlet and outlet means for a flow of coolant circulating through said cavities. Hereby the substantial amount of heat generated by the pressing of the tobacco is removed in a simple and effective manner. Other suitable means for cooling the walls may, however, also be taken into consideration.

This invention will now be explained in more detail with reference to the accompanying drawings, in which FIG. 1 is a diagrammatical vertical section through part of a pressing chamber in a pipe tobacco packing machine according to the invention, and

FIG. 2 is a horizontal section taken on line IIII in FIG. 1.

The drawing shows a pressing chamber 1 in the upper Wall 2 of which there is secured a funnel or hopper 3 through which the tobacco is supplied to the pressing chamber 1. Further, the pressing chamber has two stationary side walls 4 and 5, a stationary front wall 6 and a movable bottom wall 7. The rear defining wall of the parallelepipedal chamber 1 is constituted by a movable press ram 8.

The ram 8 is reciprocated towards and away from the front end wall 6 by means of a piston rod 9 carrying a cross member 10 which is secured to the ram 8, such as by screws 23. The piston rod 9 is guided in a sleeve 11 in the stationary portion of the apparatus. To the movable bottom wall 7 there is secured a piston rod 12 which is reciprocated by means of driving members, not shown. In FIG. 1, the bottom wall 7 is shown in its retracted position.

During operation of the packing machine of which the pressing chamber shown forms part, tobacco is intermitten-tly supplied in premeasured quantities through the funnel 3 and falls down into the pressing chamber 1 when the ram 8 assumes the position shown and the bottom wall 7 has been displaced to its extreme forward position in which it contacts the front wall 6 to close the bottom of the chamber 1, i.e. to the right in FIG. 1. Next, the ram 8 is moved forward by actuation of driving members, not shown, for the piston rod 9, whereby the tobacco is compressed in the front portion of the chamber 1 against the Wall 6. Whilst the ram 8 remains in its extreme front position, the bottom wall 7 is then withdrawn, i.e. to the position shown in FIG. 1, and by means of a discharge ram 13 which is guided laterally by the front wall 6 protruding past the end faces of the side walls 4 and 5, and which is displaceable up and down along the wall 6, the compressed quantity of tobacco is pushed down through the open bottom of the chamber into a package envelope, not shown, for example a bag or pouch, which has in advance been brought into position under the pressing chamber. Then, the ram 13 ascends, the bottom Wall 7 is moved forward, and the ram 8 is retracted whereafter the operations described are repeated with a fresh portion of tobacco.

The Walls of the pressing chamber 1 which during the pressing operation get into contact with the tobacco consist--in addition to the front wall 6 and the underside of the ram 13-of two metal slabs or plates 14 and 15 recessed in one each of the side walls 4 and 5' of the chamber, a metal slab or plate 16 secured to the ram 8 and a metal slab or plate 17 which constitutes part of the composite chamber bottom wall 7. The said components 13-17 are adapted to be cooled during operation of the machine by means of a circulating ICOOlElIlt such as brine, each of the components being provided with a system of cooling channels with associated inlet and outlet fittings.

In the vertical discharge ram 13 the said fitting for the system of cooling channels generally designated by 18 are provided in the upper portion, not shown, of the ram. In the bottom plate 17, the fittings are mounted at the rear ends of two longitudinally extending cooling channels 24 which at the front end of the plate communicate through a transversely extending channel 25. As far as the plates 14 and 15 are concerned, the fittings are provided in the associated side walls 4 and 5, respectively, said walls being provided with connecting channels 19 leading to the actual cooling channels 26 in the plates. The plate 16 is provided with a system of cooling channels 27 which are in communication with two longitudinally extending connecting channels 28 in the ram 8. The fittings, not shown, may for example be in the form of nipples which are screwed into the cooling channels or the connecting channels, respectively, and which are externally adapted to be connected to flexible hoses, at any rate as far as the movable parts are concerned.

The parts of the pressing chamber which during operation get into contact with the tobacco, i.e. the front wall 6, the discharge ram 13, and the plates 14-17, are preferably made of metal, amongst other things in order to obtain good heat-conductivity and to obtain a smooth surface. At its outer side the front wall 6 is insulated by means of an insulating material 20, and as far as the other walls are concerned a suitable heat insulation is provided, for example by using a poor heat-conductive material for the side walls 4 and 5, the ram 8 and a plate 21 interposed between the plate 17 and a cross-head 22, to which the piston rod 12 is secured. The parts 17, 21 and 22 are secured to each other and constitute in combination the chamber bottom wall 7. For guiding the bottom wall during its reciprocating displacement there may, at the sides of the cross-head 22, be provided rollers which are guided in grooves at the inner sides of the walls 4 and 5.

During operation of the packing machine, the abovementioned fittings connected to the cooling channels 18,

24, 25, 26, and 27 are connected to an outer circulation circuit for a coolant which is cooled outside the pressing chamber, for example in a compressor cooling unit, to a suitable low temperature sufficient for ensuring that the inner surfaces, facing the pressing chamber 1, of the cooled components have a temperature slightly below the dew point of the air. Thus, a thin film of water will be formed on the said surfaces of the pressing chamber, the press ram and the discharge ram owing to the condensation of the air moisture, which film has turned out to function as an excellent lubricating means that effectively prevents casing substances of the tobacco or tobacco parts from sticking to said surfaces. It may be expedient to provide for adjusting the temperature of the coolant or brine so that in any circumstance the required cooling of the walls is ensured but so that an unnecessarily intensive cooling is avoided. An excessive cooling is unwanted both for economic reasons and because the said lubricating effect of the condensing water vapours will be reduced if the cooling becomes so intensive as to produce white frost on the walls. In a practical embodiment, it has proved advantageous to maintain a temperature of the circulating coolant of about 0 C.

I claim:

1. An apparatus for intermittently pressing quantities of tobacco particularly pipe tobacco, comprising means defining a pressing chamber, including stationary wall members and a movable press ram, hopper means for supplying tobacco to said pressing chamber, means for reciprocating said press ram to vary the volume of said pressing chamber and means for ejecting a portion of tobacco from said pressing chamber after being compressed, wherein said wall members and said press ram are hollow and provided with inlet and outlet means for circulating a coolant through the interior of said wall members and press ram.

2. A method for intermittently pressing quantities of tobacco particularly pipe tobacco with a pressing machine comprising means defining a pressing chamber, including stationary wall members and a movable press ram, hopper means for supplying tobacco to said pressing chamber, means for reciprocating said press ram to vary the volume of said pressing chamber and means for ejecting a portion of tobacco from said pressing chamber after being compressed, wherein said wall members and said press ram are hollow and provided with inlet and outlet means for circulating a coolant through the interior of said wall members and press ram, said method comprising circulating a coolant through said inlet and outlet means at a temperature sufficient to cool the surfaces of the pressing chamber facing the tobacco to a temperature below the dew point of the air in the chamber so that condensation forms on said surfaces and the tendency for the tobacco to stick to said surfaces is reduced.

References Cited UNITED STATES PATENTS 1,888,805 11/1932 Peterson 13l78 1,979,648 11/1934 Stelzer 13179 2,899,317 8/1959 Hensgen et al. 17-32 X SAMUEL KOREN, Primary Examiner.

H. P. HEELEY, Assistant Examiner.

Claims (1)

1. AN APPARATUS FOR INTERMITTENTLY PRESSING QUANTITIES OF TOBACCO PARTICULARLY PIPE TOBACCO, COMPRISING MEANS DEFINING A PRESSING CHAMBER, INCLUDING STATIONARY WALL MEMBERS AND A MOVABLE PRESS RAM, HOPPER MEANS FOR SUPPLYING TOBACCO TO SAID PRESSING CHAMBER, MEANS FOR RECIPROCATING SAID PRESS RAM TO VARY THE VOLUME OF SAID PRESSING CHAMBER AND MEANS FOR EJECTING A PORTION OF TOBACCO FROM SAID PRESSING CHAMBER AFTER BEING COMPRESSED, WHEREIN SAID WALL MEMBERS AND SAID PRESS RAM ARE HOLLOW AND PROVIDED WITH INLET AND OUTLET MEANS FOR CIRCULATING A COOLANT THROUGH THE INTERIOR OF SAID WALL MEMBERS AND PRESS RAM.

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