US3095883A

US3095883A - Continuous rod cigarette-making machines

Info

Publication number: US3095883A
Application number: US18926A
Authority: US
Inventors: Morris James Ernest
Original assignee: Molins Machine Co Ltd
Current assignee: Molins Machine Co Ltd
Priority date: 1959-04-17
Filing date: 1960-03-31
Publication date: 1963-07-02
Anticipated expiration: 1980-07-02
Also published as: GB953861A; DE1218326B; FR1262620A; GB953792A; GB953862A

Description

July 2, 1963 J. E. MORRIS CONTINUOUS ROD CIGARETTE-MAKING MACHINES 3 Sheets-Sheet 1 Filed March 31, 1960 I'll'lll ll'lll'llll ATTORNEKS" 3 Sheets-Sheet 2 J. E. MORRIS CONTINUOUS ROD CIGARETTE-MAKING MACHINES Fig.2.

0 O O O O O O 0 G O O O July 2, 1963 Filed March 31, 1960 0 O O 0 0 O 0 July 2, 1963 J. E. MORRIS CONTINUOUS ROD CIGARETTE-MAKING MACHINES 3 Sheets-Shee i; 3

Filed March 31, 1960 /NVENTOE V4010: Iinfsf' MW).

v BY

Wm l(/Z 2TL1 ATTORNEB United States Patent 'Ihis specification is concerned with continuous rod cigarette-making machines in which a continuous tobacco filler is formed on an air pervious conveyor, and is held to the conveyor by suction. To form the tobacco filler, a duct is provided which has its outlet in communication with the conveyor, and cut tobacco is introduced into the inlet end of the duct to be impelled toward the conveyor by means of air drawn through the duct by the suction applied to the conveyor.

Some of the air which is drawn through the duct and the conveyor is discharged to the atmosphere, and further air is drawn into the inlet end of the duct to replace this discharged air. If this further air which is drawn into the duct has already passed over parts of the machine, such as air pumps which produce the airflow, it will already have had its temperature raised and will, therefore, not be so efiective in lowering the temperature of the air in the duct.

It is an object of the present invention to provide a pneumatic system in a continuous rod cigarette-making machine as set out above, in which further air is drawn from the atmosphere into the duct at such a position that it has not had its temperature raised by being drawn over air pumps, and will substantially all be drawn through the duct.

With a continuous rod cigarette-making machine in which a continuous filler is formed on an air pervious conveyor by being introduced into a duct through which air is drawn, it can be arranged that the denser particles of tobacco are not impelled through the duct to become part of the tobacco filler. This can be done by arranging for the introduction of the tobacco toward the inlet of the duct at substantially a right angle to the duct, so that the denser particles will not be turned into the duct by the airflow, but pass along to a further duct to be collected. These denser particles of tobacco may carry with them, by collision or entanglement therewith, less dense particles of tobacco which should have been incorporated in the tobacco filler.

It is a further object of the invention to utilize the further air to return these less dense particles of tobacco to the duct to be impelled to the air pervious conveyor.

Apparatus made and operating in accordance with the present invention will now be described by way of example with reference to the accompanying drawings of which:

FIGURE 1 shows, in side elevation and with parts broken away, means for forming a continuous tobacco filler in a continuous rod cigarette-making machine;

FIGURE 2 shows diagrammatically, with parts broken away, an end view of the apparatus shown in FIGURE 1, together with a diagrammatic representation of air supply means;

FIGURE 3 shows a modified arrangement and is a similar view to part of FIGURE 2, and

FIGURE 4 shows to an enlarged scale, a plan view of a short length of a perforated conveyor band on which the continuous tobacco filler is formed.

The FIGURES 1, 2, 3 correspond generally to FIG- URES 6, 7 and respectively of US. application Patent No. 3,030,965, patented April 24, 19 62.

Referring first to FIGURES 1 and 2, a carded conveyor ice drum 10, arranged to rotate in the direction shown by the arrow in FIG. 2, receives cut tobacco in bulk on the upper part of its surface and carries it past a carded refuser roller 11. The drum 10, the roller 11 and a wall 12 form the lower (part of a tobacco hopper which is somewhat similar to that disclosed in the United States Patent No. 3,062,357, patented November 6, 1962.

A fast-rotating picker roller 13- delivers tobacco from the carding of drum '10 and impels it across a guide plate 14 towards and at an angle to the entry 43 to a first duct 19 which extends upwards to a suction chamber 22.

Between the entry 43 to the duct 19 and the picker roller 13 is a pneumatic suction system including a pertorated cylinder '16 arranged to rotate, in the direction shown by the arrow, about two fixed

members

17 and 18. A second duct 15 extends upwards from the perforated roller 16 and is joined thereto by conventional air sealing means. Means to introduce cut tobacco into the duct 19 comprises the picker roller 13, the guide plate 14 and the suction means.

The first duct 19 comprises closely-spaced

side walls

20 and 21 and is of substantial height. The length of the duct 19 corresponds closely to the length of the drum 10 and of the

rollers

11 and 13 shown in FIG. 1. The first duct 19 terminates at a suction chamber 22 which extends perpendicularly to the plane of FIGURE 2 and has one part which extends along the top of the duct :19 and another part which extends leftwardly beyond the duct 19 as seen in FIG. 1. The duct 19 is also inclined at a small angle in a plane perpendicular to the plane of FIGURE 2. At the lower end of wall 20 is a cascade of curved guide vanes 50.

A conveyor in the form of a travelling perforated conveyor band or tape 41 is shown in section in FIGURE 2 and has one portion which extends between the first duct 19 and one part of the suction chamber 22 and another portion which extends beneath the other part of the suction chamber 22. This latter portion of the band 41 is thus exposed to atmosphere. The band 41, as shown in FIGURE 1, carries the tobacco filler above a trimming device 7 and, after being trimmed the filler is transferred on to a paper Web 8. The direction of travel of the band 41 is in the direction of inclination of the first duct 19. A plan view of a short length of the band 41 is shown to an enlarged scale in FIGURE 4.

A pumping means is provided to draw air through the first and

second ducts

19 and 15 and comprises first and

second suction pumps

32 and 23 respectively. The second pump 23 is the smaller of the two and has its inlet connected to a conduit or ducting 24 which comm-unicates with the outlet of the second duct 15. Provided in the conduit 24 is a dust separator 25 (which is similar in construction to the dust-separating device 81 in copending United States Patent No. 3,030,965). The outlet of the pump 23 is connected to a conduit 26 which leads to one end of an air manifold 27 which delivers the air from the pump 23 to a diffuser 28 at the entry to which is provided a honeycomb matrix 44 to direct air into the manifold 27 to flow into the diffuser 28.

The diffuser 28 comprises a curved plate 29 perforated at 45 and with its convex surface facing upwardly and, beneath the remote end of the plate 29, a chamber 30. The top of the diifuser is formed by a sheet of expanded metal 31 which is louvred to direct air in the direction indicated by the arrows towards a perforated plate 37 which extends between the guide plate 14 and a chamber 38. Extending between the chamber 38 and the cascade of curved guide vanes 50* is a wall 48 containing an aperture 49 in the form of a slot extending almost entirely across the substantially horizontal dimension of the duct 19 as seen in FIG. 1.

The plate 37, the wall 48 and the chamber 3% define a further duct 6%) which is closed and its lower end by the lower wall of the chamber 38. This duct 60 is arranged in the path of the tobacco particles impelled across the guide plate 14 and heavier particles of tobacco such as pieces of stalk or stem pass down the duct 60 into the chamber 38. Air is drawn through aperture 49 to flow up duct 60 in the opposite direction to the flow of these heavier particles.

The first and larger suction pump 32 has its inlet connected to a conduit 33 which communicates with the suction chamber 22. The outlet of the pump 32 is connected to a conduit 34 which in turn leads to the inlet of a multi-unit cyclone 35 which discharges air to atmospherc. The outlet of the dust separator 25 is connected by pipe 36 to conduit 33 and a valve 46 is provided in pipe 36 to control flow from the dust separator 25 to the conduit 33.

The apparatus described operates in the following manner.

Air is drawn through the aperture 49 in the plate 48 and through the perforated plate 37 by the

pumps

23 and 32. The pump 23 draws an air current into the second duct 15 through the rotating perforated cylinder 16 and this air current passes through the stream of tobacco particles impelled across the guide plate 14 and turns the majority of the particles to flow in a substantially arcuate path through an angle into the entry 43 of the first duct 19. The heavier particles such as pieces of stalk or stem, due to their momentum, are not turned into the arcuate path but pass down the duct 6%) into the chamber 38. The air drawn through the aperture 49 flows up the duct 60 in the opposite direction to the direction of these heavier particles and removes therefrom any lighter particles and conveys them to the entry 43 to the duct 19. These lighter particles may have been carried into the duct 60' by collision with heavier pan tticles or may have become entangled therewith. The quantity of air flowing through the aperture 49 will be a factor in determining the amount of winnowings present in the chamber 38.- The first pump 32 draws an air flow from the conduit-33 and suction chamber 22 and up through the first duct 19 and perforated conveyor band 41. This airflow acts on the tobacco particles to accelerate and impel them up the duct 19 substantially in the form of discreteparti-cles to form a continuous tobacco filler on the perforated conveyor band 41. The cascade of-curved guide vanes SGacts to impart to the airflow into the duct 19 a component of flowin the direction of inclination of the duct 19, i.e., in the direction tobacco filler and the portion of the band 41 to the left of the duct 19 as seen in FIGURE 1. The airflow from the duct 19, includingair from atmosphere is drawn into the suction box 22, through conduit 33 and into the first pump 32 and is discharged to atmosphere from the multiunit cyclone 35 via the conduit 34. Any dust and short particles of tobacco in the air are retained in the cyclone 35. These short particles of tobacco are commonly called shorts.

The air current is drawn from the second duct 15 through the conduit 2 into the second pump 23 and is passed to the manifold 27 through the conduit 26. The dust separator 25 is provided to extract any tobacco dust which is drawn through the perforated cylinder 16 with the air current and to discharge it through pipe 36 into conduit 33 so that it may eventually be removed by the cyclone 35.

In spite of the presence of the dust separator 25', a certain amount of dust and also probably some shorts are carried by the air current into the manifold 2'7. As

4 the air current flows through the matrix 44- the dust and shorts tend to travel over the curved plate 29 to its right-hand extremity, due to their momentum, to fall into chamber 30, whilst the air diffuses upwards through the expanded plate 31. The perforation 45 is provided in the piate 29 to allow a small flow of air into the chamber 39' over the end of curved plate 29 to escape and joint the main airflow through the expanded plate 31. In some instances it may be desirable to feed into the tobacco passing up the first duct 19 to form the tobacco filler a proportion of the shorts which have been carried through the perforated conveyorband 41 by the airflow and accordingly a further dust separator 39 may be provided in the conduit 34 and the shorts, together with some dust, which are extracted by the dust separator 39 are passed into conduit 30 which leads to the duct 19 just below the tobacco filler. A valve 47 is provided in conduit 49 to control the flow from the dust separator 39. if desired, a conduit 42 may be provided to convey a small proportion of the airflow from near the top of the duct 19 to the conduit 15 leading to the conduit 24. The effect of this is to increase the velocity of the airflow in the duct 19 in relation to the quantity of air drawn through the tobacco filler by the pump 32 and is an example of the invention disclosed in United States Patent No. 3,919,793, patented February 6, 1962.

Substantially all the air leaving the diffuser 23 is drawn through the perfonated plate 37 to be drawn either through the perforated cylinder 16 or into the first duct 19. A substantial proportion of fresh air from atmosphere, which will be substantially equal to the airflow through the duct 19, will also be drawn in. fresh air is drawn up through the perforated plate 37 and wiil first have flowed over parts of the machine, such as the

pumps

23 and 32, and in so doing will have had its temperature raised. The provision ofthe aperture 49 reduces the suction exerted on the perforated plate 37 by the

pumps

23 and 32 and thus reduces the quantity of air drawn therethrough and allows a substantial proportion of the fresh air to be drawn in above the perforated plate 37. This air drawn through the aperture 49 comes from a region where its temperature has not been raised in cooling the machine and is admitted to the duct 19 at a location immediately prior to the point of introduction of the tobacco into the duct 19.

The airflow which is passed through the cut tobacco in the first duct 19 is conditioned by heat due to work done on the air originating in the first and

second pumps

32 and 23 and by the heat lost to the ambient atmosphere by conduction or radiation from parts of the machine. However, the temperature of the airflow as it passes through tl e out tobacco is lowered by the fact that a sub stantial proportion of the airflow is drawn from atmosphere into the duct 19. Thus, other things being equal, the alteration to the characteristics of the tobacco resulting from contact with the airflow, e.-g., the reduction in moisture content, will be reduced, in comparison with the case where no fresh air is drawn in and also in comparison with the case when all the fresh air is drawn up through the perforated plate 37. The moisture content desired in the tobacco in the tobacco filler will difier amongst cigarette manufactures but the invention provides at least that within a certain range of ambient temperatures and with the moisture content of the tobacco in the hopper within a certain range apparatus of the invention can be made to give a moisture content of the tobacco after contact with the airflow within a desired range.

In FIGURE 3 there is shown a modification of the apparatus shown in FlGURES l and 2 and like numerals will be used where possible. As in the previous embodiment, particles of tobacco are impelled across the guide plate 14 by the pickerroller 13towards the entry 43 to the duct 19. In this embodiment the fixed wall 48 is replaced by a movable wall 148. The wall M3 is hingedly mounted at its left hand end by a flexible strip 62 and Part of this carries at its right hand end the cascade of guide vanes 50, and a sealing strip 63 which bears against the base of the wall 20 or" the duct '19. The wall 148 can thus be adjusted in position as indicated by the full and dotted line positions shown and can be secured in any desired position by means of the screw 64 which passes through a slot 65 in the lug 66 which is secured to the wall 148. The screw 64- is threaded into a side plate 67. The fixed perforated plate 37 is replaced by an adjustable perforated plate 137 which is hinged at its right hand end about a pin 70 and its left hand end carries a plate '71 which slides over a member 72 in an air-sealing manner. The plate 137 is clamped in position by means of a setscrew 73 which is threaded into the member 72.

The wall 148 is imperforate and an [aperture 149 is provided near the top of the chamber 58 and is covered by a perforated plate 74. As with the previous embodiment, the heavier, or at least the denser particles of tobacco, i.e., particles of greater mass in relation to the air drag they experience, such as pieces of stalk or stem pass down the duct 160 to fall into the chamber 38. The duct 169 corresponds to the duct 60' in FIGURE 2. The air flowing up the duct 160 from the aperture 149 removes the lighter particles and conveys them to the entry 43 of the duct 19'.

in this embodiment the general orientation and configuration of the duct 160 can be varied by adjustment of the walls .148 and 137. Thus the throat 61 of the duct 160 can be varied from that produced when walls 148 and 137 are in the full line position to that produced when these walls are in their dotted line position, in which case a higher air velocity will be produced in the throat 61, or the mean line of the duct 160 cm be moved by mow'ng both walls in the same direction.

The higher the velocity of air in the throat 61 the greater will be the aerodynamic force acting on the particles passing down the duct 160 and thus a smaller proportion of them that will pass into the chamber 38 as winnowings, and a greater proportion of them will be turned back to the entry 43. Thus by suitable adjustment of the walls 137 and 148 a selected proportion of the denser particles of the tobacco from the picker roller 13 may be winnowed into the chamber 38.

As with the previous embodiment the air that is admitted through aperture 149 is cooler than the air admitted through the plate 137 and forms a substantial proportion of the fresh air drawn in.

What I claim for my invention and desire to secure by Letters Patent is:

1. Ina continuous rod cigarette-making machine having a perforated conveyor, a suction chamber in communication with one face of the conveyor, a straight first duct having an inlet and an outlet, the inlet of the first duct being spaced from the conveyor and the outlet of the first duct being in communication with the other face of the conveyor, and tobacco feeding means to introduce cut tobacco into the inlet of the first duct along a path at substantially la right angle to the first duct, a pneumatic system comprising a first air pump having an inlet and an outlet, first air ducting having an inlet and an outlet, the inlet of the first air ducting being connected to the suction chamber, and the outlet of the first air ducting being connected to the inlet of the first air pump, whereby the first air pum draws air through the first duct, the conveyor and the suction chamber to impel the tobacco through the first duct to the conveyor to form a continuous tobacco filler on the conveyor and hold it thereto, a second duct having an inlet and an outlet, the inlet of the second duct being situated adjacent the inlet of the first duct and between the inlet of the first duct and the path of the tobacco, second air ducting having an inlet and an outlet, the outlet of the second duct being connected to the inlet of the second air ducting, a second air pump having an inlet and an outlet, the outlet of the second air ducting being connected to the inlet of the second air pump, whereby the second air pump draws air across the path of the tobacco to assist in turning it into the first duct, a third duct having one end in communication with the inlet of the first duct and having its other end closed, the tobacco feeding means and air pumps being located on one side of the first and third ducts, third air ducting having an inlet and an outlet, the inlet of the third air ducting being connected to the outlet of the first air pump, and the outlet of the third air ducting being open to the atmosphere at a position remote from the inlet of the first duct, and fourth air ducting having an inlet and an outlet, the inlet of the fourth air ducting being connected to the outlet of the second air pump, and the outlet of the fourth air ducting being open to atmosphere adjacent the inlet of the first duct, whereby the air from the second air pump is drawn again into the first and second air ducts together with a first quantity of air from atmosphere, and means defining an aperture in a side of the third duct remote from the tobacco feeding means and air pumps to admit a second quantity of air from atmosphere into the third duct to be dnawn into the first duct, which second quantity of air is cooler than the first quantity of air.

2. A pneumatic system in a cigarette making machine as claimed in claim 1 wherein the end of the third duct which is in communication with the inlet of the first duct is arranged in the path of the tobacco impelled toward the inlet of the first duct by the tobacco feeding means, and the other and closed end of the third duct is enlarged to form a chamber, whereby the second quantity of air assists in turning the tobacco through the first angle into the first duct and denser particles of tobacco which are not turned through the first angle pass into the third duct to flow along it into the chamber, the quantity of denser particles which passes into the third duct being determined by the magnitude of the second quantity of air and the means defining an aperture in the side of the third duct is spaced from the inlet of the first duct, whereby the denser particles flow along the third duct in the opposite direction to the second quantity of air which carries back to the inlet of the first duct lighter particles of tobacco carried into the third duct by collision or entanglement with the denser particles, the quantity of lighter particles so carried back being determined by the velocity of the air flowing through the third duct.

"3. A pneumatic system in a cigarette making machine as claimed in claim 2 wherein the third duct has walls which are adjustable toward and away from each other to provide a variable throat area whereby the velocity of the air flowing therethrough can be varied.

References Cited in the file of this patent UNITED STATES PATENTS 132,935 Suggett Nov. 12, 1872 973,698 Pugibet Oct. 25, 1910 1,869,395 Stelzer Aug. 2, 1932 1,984,811 Rundell Dec. 18, 1934 1,999,120 Werner Apr. 23, 1935 FOREIGN PATENTS 47,720 Denmark Aug. 23, 1933 1,179,992 France Dec. 29, 1958 1,229,066 France Mar. 21, 1960 764,551 Great Britain Dec. 28, 1956

Claims

1. IN A CONTINUOUS ROD CIGARETTE-MAKING MACHINE HAVING A PERFORATED CONVEYOR, A SUCTION CHAMBER IN COMMUNICATION WITH ONE FACE OF THE CONVEYOR, A STRAIGHT FIRST DUCT HAVING AN INLET AND AN OUTLET, THE INLET OF THE FIRST DUCT BEING SPACED FROM THE CONVEYOR AND THE OUTLET OF THE FIRST DUCT BEING IN COMMUNICATION WITH THE OTHER FACE OF THE CONVEYOR, AND TOBACCO FEEDING MEANS TO INTRODUCE CUT TOBACCO INTO THE INLET OF THE FIRST DUCT ALONG A PATH AT SUBSTANTIALLY A RIGHT ANGLE TO THE FIRST DUCT, A PNEUMATIC SYSTEM COMPRISING A FIRST AIR PUMP HAVING AN INLET AND AN OUTLET, FIRST AIR DUCTING HAVING AN INLET AND AN OUTLET, THE INLET OF THE FIRST AIR DUCTING BEING CONNECTED TO THE SUCTION CHAMBER, AND THE OUTLET OF THE FIRST AIR DUCTING BEING CONNECTED TO THE INLET OF THE FIRST AIR PUMP, WHEREBY THE FIRST AIR PUMP DRAWS AIR THROUGH THE FIRST DUCT, THE CONVEYOR AND THE SUCTION CHAMBER TO IMPEL THE TOBACCO THROUGH THE FIRST DUCT TO THE CONVEYOR TO FORM A CONTINUOUS TOBACCO FILLER ON THE CONVEYOR AND HOLD IT THERETO, A SECOND DUCT HAVING AN INLET AND AN OUTLET, THE INLET OF THE SECOND DUCT BEING SITUATED ADJACENT THE INLET OF THE FIRST DUCT AND BETWEEN THE INLET OF THE FIRST DUCT AND THE PATH OF THE TOBACCO, SECOND AIR DUCTING HAVING AN INLET AND AN OUTLET, THE OUTLET OF THE SECOND DUCT BEING CONNECTED TO THE INLET OF THE SECOND AIR DUCTING, A SECOND AIR PUMP HAVING AN INLET AND AN OUTLET,