US3473537A

US3473537A - Device for forming a compressed rod of tabacco

Info

Publication number: US3473537A
Application number: US584409A
Authority: US
Inventors: Friedrich Wilde; Johannes Herrmann
Original assignee: Tabak & Ind Masch
Current assignee: Tabak & Ind Masch; VEB TABAK und IND MASCHINEN DRESDEN
Priority date: 1966-10-05
Filing date: 1966-10-05
Publication date: 1969-10-21
Anticipated expiration: 1986-10-21
Also published as: GB1119294A

Description

OCR 21, 1969 F. wlLDE ETAL. 3,473,537

DEVICE FOR FORMING A CMPRESSED ROD 0F TOBACCO Filed oct. 5, lese FiG. 2

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3 9B w INVENTORS n I6 n FRIEDRICH WILDE JOHANNES HERRMANN United States Patent O 3,473,537 DEVICE FUR FJRMHNG A COlt/IPRESSED RUB F TQBACC Friedrich Wilde and .iohannes Herrmann, Dresden, Germany, assignors to VEB Tabakund lndustrieanaschinen Dresden, Dresden, Germany Filed Get. 5, 1966, Ser. No. 584,409 Int. Cl. A24c 5/.78

U5. Cl. 131-84 5 Claims ABSTRACT 0F THE DISCLGSURE A device for forming strands of tobacco fibers into a tobacco rod including a `conduit on the circumference of a suction wheel in which the conduit is foraminous. The recesses are disposed at spaced locations in the conduit whereby the tobacco fibers are slowed down in the area of said recesses to thereby build up the same into a tobacco rod.

The device further has a foraminous belt located adjacent to the tobacco stream of the suction wheel.

The invention relates generally to a device for forming a compressed rod of tobacco and in particular to a rod which is densied at predetermined portions. This rod of tobacco is made from a tobacco stream.

When making cigarettes from a rod of tobacco as indicated above, difticulties exist in maintaining an even amount of tobacco at the location where the rod is cut into cigarette lengths. It has been already suggested to provide more tobacco fillings at this location. For this purpose, different devices are known to solve the problems involved.

All the devices which are presently utilized to achieve more tobacco filling at that tobacco rod portion which will be cut to establish an end of the cigarette operate on the principal of either adding superfluous tobacco to the portion to be cut or trimming and removing tobacco from those portions of the cigarette which are not to be cut with the result that when the tobacco is cut, the rod forming and wrapping procedure densities the tobacco of the cigarette at the ends thereof and establishes the desired results. These devices are disadvantageous in that the fibrous tobacco structure is shortened due to the trimming and cut. Besides, all these mechanical measures like separating, adding and displacing the tobacco are rather uneconomical, especially with high velocity tobacco streams. These methods are unsatisfactory because of rather high fluctuations in the attained distribution of the tobacco during the trimming process.

It is therefore an object of the invention to overcome the above-mentioned shortcomings, by forming a tobacco rod provided with predetermined densiiied portions and to achieve this desired result by employing simple means which simultaneously achieve a higher speed.

It is a further object of the invention to form measured densifications on the dened places of a tobacco rod without shortening the tobacco fibers.

In accordance with the invention these objects are achieved in that the tobacco portions in the tobacco stream are guided at a high speed into a groove. The groove is provided with enlarged recesses which are disposed in even distances from each other. The tobacco portions are slowed down and positioned in the groove by removing air therefrom, so that the tobacco portions iill the inner chamber of the groove. Subsequently, the tobacco rod whose cross-sectional area is increased at predetermined places will be transferred to a known l cigarette forming device and finally densied with a higher density at the end portions of the cigarettes.

3,473,537 Patented Oct. 2l, 1969 The inventive device comprises a channel disc provided with a circumferentially arranged conduit, the cross section of which is selectively varied by recesses, formed in a perforated base circumferentially surrounding the disc and forming a wall portion of the conduit. The advantage of the inventive device consists in that tobacco densifications of desired volume and at predetermined positions along the rod may be formed automatically, by a simple reliance of pneumatic pressure axially directed forcing the tobacco stream to till the predefined volume, without employing mechanical means or using a superfluous quantity of tobacco. This simple procedure operates reliably even at the highest possible rod forming speeds, due to the momentum of the tobacco stream, so that the known advantages of the cigarette end compaction are achieved with less mechanical means by simultaneously increasing the production output of the machine and by lowering the construction expenses.

The invention will be more clearly understood from the following description of a specific embodiment of the invention together with the accompanying drawings, in which:

FIG. l is a vertical sectional view of a rod forming device according to the invention;

FIG. 2 is a sectional view taken alon-g line II-II of FIG. 3; and

FIG. 3 is an enlarged sectional view of the guide plate and the separating wall, taken along line lI-II of FIG. l, with some parts omitted for clarity.

With respect to the subject of the invention it should be noted that numerous embodiments for these devices are possible. However, a preferred embodiment is used as shown in the accompanying drawings in accordance with the inventive method. With reference to FIG. 1 of the drawing, it is seen that radial depressions are formed in a rotating grooved disc 1. Channel disc 1 is in communication with a supply conduit 2, a portion of this conduit being shown in FlG. 1, through which a tobacco stream is guided. Conduit 2 extends tangentially of a -groove 3, which is formed on the circumference of channel disc 1. The base 18 of groove 3 is interspersed with line holes and is provided with a plurality of enlarged rounded recesses 4 disposed intermittently about its circumference. A

cigarette paper web 5 is guided opposite and parallel with respect to conduit 2 which receives the tobacco rod and guides the same into a cigarette forming device 6. Channel disc 1 is encompassed by perforated band 8 which is guided over rollers 7, and extends from conduit 2 to cigarette paper web 5 so that perforated band 8 forms a closed conduit 3 with the ange portions 17 of disc 1 and the perforated base 18. Member 19 is a stationary block in the form of a semi-circular disc which is disposed with its surface adjacent the inner side of base 18. This element 19 closes the perforations in base 18 and thereby serves to close the left half of the interior of the suction wheel as seen in FIG. 2 so that only the right hand half of the interior thereof may comprise a suction chamber. An adjustable partition 9 is provided within the active part and separates the vacuum chamber into a starting zone 10 and end zone 11. The pressure which is present in starting zone 10 and end zone 11 is adjustable by means of a movable baflle plate 13. A vacuum conduit 12 for producing a vacuum within the vacuum chamber of the disc 1 is connected to a vacuum pressure source (not shown).

The operation of the device is as follows:

The tobacco stream which is introduced into the rod groove 3 at high velocity is of low density. At the end of zone 11 where this stream collides with the already formed but uncut tobacco rod which is moving at the considerably lower speed of the channel wheel which is driven by conventional means which are diagrammatically shown at 30. The tobacco stream density is increased until it corresponds to the tobacco rod density. This occurs before the stream is transferred into cigarette-paper web 5.

Suction pipe 12 acts to create a vacuum in the space defined by the suction pipe 12 and suction chamber 15 inside the grooved disk 1. This space is divided into two portions by the positioning of partition 9 and baffle plate 13. Partition 9 effectively divides the suction chamber 15 into two portions as can be seen in PIG. 2. As can be seen in the drawings baie plate 13 and partition 9 are hinged on shaft 22 and have portions which effectively divide the suction pipe 12 into two portions. Therefore, if in FIG. 2, baffle plate 13 is positioned in an upward vertical direction and if partition 9 is positoned rghtwardly horizontally, it can be seen that the suction pipe 12 and suction chamber 15 have been so divided so that 3A of the suction acts on section 11 an 1A of the suction acts on volume 10. Therefore a different effective pressure is maintained in each section (10, 11).

The effective pressure in each of these zones and the angular extent of the disk over which it will act are predetermined based on factors to be subsequently discussed. Once having been so determined, the partition 9 is rigidly connected, at this pre-determined position, to the shaft by means of a pin 23. Shaft 22 is clamped by means of knurled nut 25 against the end faces of the bushing 24, while at the same time the end faces of the hinge parts of baffle plate 13 are pressed against the end faces of the hinge parts of partition 9. Bushing 24 is pressed tightly into the front bore of suction pipe 12. This effects a stationary placement of baille plate 13 and partition 9 at pre-determined positions.

The suction effect in Zone 10 is designed to be less than the vacuum effect of zone 11. As the tobacco stream enters conduit 2 it is slowed down in zones 10 and 11 as a result of the vacuum effect of zones 10 and 11 and because of frictional considerations. This effect results in the slowdown in two ways: first, the tobacco stream is pulled against the perforated base 18 and this increases the friction between the stream and the disk 1, and secondly, as the density is thereby increased friction within the tobacco stream is increased. This effect, therefore, results in a velocity gradient as the stream progresses towards the cigarette forming device 6. As the stream approaches the end of zone 11 the stream has a velocity greater than the tobacco rod downstream of the forming device. The band perforations permit air to flow radially inwardly through the tobacco shreds in the conduit, through the perforated base 118 and into the suction chamber 15. This results in the complete filling of the total cross-sectional area 16 formed by rod groove 3, perforated band 8 and flanges 17. The recesses 4, which are filled with a larger quantity of tobacco are so arranged that they form the end portions of the cigarette so that upon the cutting of the cigarete the cigarete will be densified at the ends thereof.

In accordance with the foregoing described device, it is apparent that because of the recesses 4 formed in rod lgroove 3 and because of the pneumatic construction, a tobacco rod may be formed with defined and desired densications at predetermined locations without shortening the fibrous structure of the tobacco.

What is claimed is:

1. A device for forming tobacco fibers into a tobacco rod to be supplied to a cigarette forming apparatus, said rod having portions thereof each having an increased quantity of fibers therein than that in the remainder thereof, comprising a conduit for receiving an air current at a predetermined flow rate means for feeding said tobacco into said air current to form a tobacco stream, a rotating suction wheel having a circumferential groove and a foraminous periphery and having depressions radially directed therein, a foraminous belt located adjacent to the exterior of said circumferential groove of said wheel forming a closed conduit therewith, and means for applying a vacuum to the periphery of said Suction wheel for withdrawing air from said tobacco stream, said tobacco stream having a greater velocity than said channel wheel conduit, said tobacco rod having the same Velocity as said channel wheel conduit, said tobacco stream colliding into said tobacco rod whereby a tobacco rod is formed having predetermined densifications spaced along its length.

2. A device as claimed in claim 1 wherein said means for applying a vacuum to said suction wheel includes a vacuum chamber means.

3. A device as claimed in claim 2 wherein said conduit is directed to the periphery of said suction wheel and coupled to said circumferential groove, and said vacuum applying means is located at the side of said groove nearer to said vacuum chamber means.

4. A device as claimed in claim 1 wherein said depressions are equally spaced from one another.

5. A device as claimed in claim 4 wherein said depressions are arcuate to thereby insure a smooth buildup or' said tobacco rod.

References Cited UNITED STATES PATENTS 1,721,117 7/1929 Hopkins. 2,236,579 4/ 1941 Rundell. 2,290,896 7/ 1942 Stein. 2,969,104 1/1961 Schubert et al. 3,074,413 1/ 1963 McArthur. 3,094,127 6/ 1963 Gamberini. 3,244,184 4/ 1966 Petr.

FOREIGN PATENTS 941,854 11/ 1963 Great Britain.

JOSEPH S. REICH, Primary Examiner