US3826065A

US3826065A - Air separator for tobacco feed systems

Info

Publication number: US3826065A
Application number: US00275800A
Authority: US
Inventors: F Labbe
Original assignee: MOLINE Ltd
Current assignee: MOLINE Ltd; MOLINE Ltd GB
Priority date: 1971-07-28
Filing date: 1972-07-27
Publication date: 1974-07-30
Anticipated expiration: 1991-07-30
Also published as: DE2237292A1; DE2265322A1; DE2237292C3; GB1397726A; DE2265322C3; DE2265322B2; IT964808B; DE2237292B2; JPS5510227B1; FR2147736A5

Abstract

Apparatus for pneumatically feeding tobacco to a cigarette making machine includes an air separator comprising a chamber having an inlet of given cross-sectional area for receiving a flow of tobacco carried by air, a deflector which deflects the tobacco along a curved path towards a tobacco outlet, and an air outlet remote from the deflector, the tobacco outlet having a smaller cross-sectional area than the inlet, and the deflector being so shaped that it progressively reduces the transverse dimensions of the tobacco stream with the aid of centrifugal force to enable the tobacco to pass out through the tobacco outlet.

Description

United States Patent 1191 Labbe 1111 3,820,065 1451 July 30, 1974 [5 AIR SEPARATOR FOR TOBACCO FEED 3,514,159 5/1970 Labbe 302/59 SYSTEMS [75] Inventor: Francis Auguste Maurice Labbe, Primary Examine, BemaI-d Nozick Nemny'sur'seme France Attorney, Agent, or FirmCraig & Antonelli [73] Assignee: Moline Limited, London, England [22] Filed: July 27, 1972 [21 Appl. No.: 275,800 [571 ABSTRACT Apparatus for pneumatically feeding tobacco to a cig- [30] Forelgn Application Pnomy Data arette making machine includes an airseparator com- July 28, 1971 Great Britain 1. 35516/71 prising a chamber having an inlet of given crosssectional area for receiving a flow of tobacco carried Cl 55/309, 5/4 8, by air, a deflector which deflects the tobacco along 21 55/430, 55/ 131/1 1 4 curved path towards a tobacco outlet, and an air out- [51] int. Cl Bold 45/12 let remote from the deflector, the tobacco outlet havl l Field of Search 131/34 34 10; ing a smaller cross-sectional area than the inlet, and

55/459, 309, 418, 4l3, 461, 458, 432, 460, the deflector being so shaped that it progressively re- 133 9, 23 duces the transverse dimensions of the tobacco stream with the aid of centrifugal force to enable the tobacco [56] References Cited to pass out through the tobacco outlet.

UNITED STATES PATENTS 2,101,249 12/1937 Frisch 209/144 13 Claims, 8 Drawing Figures egg? 9 CONTROLLER l A J 25 36 0 /J----- Z0 0 8 1 If I l l 7 6 1 1] 1 l 1 I 1 O 6 1 O t s 7 412 24 \111/ 1 T 4 I 32 E:- l

PATENTED JUL3 01974 3, 826. 065 SHEET 1 or 3 AIR SEPARATOR FOR TOBACCO FEED SYSTEMS This invention is concerned particularly with feeding tobacco by means of air to a cigarette making machine from a primary unit in which the tobacco may, for example, be loosened and winnowed. A number of machines may in practice by supplied by one primary unit. Each machine may include a spreading device which spreads the tobacco received from the primary unit into an annular space defined by at least one rotary member so that a continuous built-up stream of tobacco can be delivered tangentially from the annular space.

According to one aspect of the invention described in US. Application Ser. No. 275,635, a cigarette making system comprises means for delivering tobacco by means of air into a pipe leading to an air separator which removes part of the air and passes the tobacco out through an outlet, without significantly reducing its velocity, to a spreading device of a cigarette making machine which deflects the tobacco into an annular space defined by at least one moving part arranged to carry the built-up tobacco stream in the annular space towards an outlet through which at least part of the built-up tobacco stream is continuously removed, preferably in an approximately tangential direction.

There is preferably no mechanical seal at the tobacco outlet of the air separator (such as would reduce the velocity of the tobacco), and the interior of the spreading device is at a pressure such as not to cause any air flow in through the tobacco outlet of the air separator. Preferably the system operates by means of suction, in which case the suction pressure in the spreading device should be at least as great as that in the air separator.

The spreading device may comprise a rotary member including a channel which has a tobacco inlet end on the axis of rotation of the rotary member, and an outlet end spaced from the axis of rotation, so that the tobacco is delivered from the spreading device with a winding action. By this means a tobacco stream can be built up in an annular space from which the stream (for example in the form of a carpet) can be fed out in a substantially tangential direction. (A spreading device in this form is described in a patent application filed simultaneously with the present application).

According to the present invention an air separator for this purpose preferably comprises a chamber having an inlet of given cross-sectional area for receiving a flow of tobacco carried by air, a deflector which defleets the tobacco along a curved path towards a tobacco outlet, and an air outlet remote from the deflector, the tobacco outlet having a smaller cross-sectional area than the inlet, and the deflector being so shaped that it progressively reduces the transverse dimensions of the tobacco stream with the aid of centrifugal force to enable the tobacco to pass out through the tobacco outlet.

According to another aspect of this invention, an air separator for use at the tobacco inlet of a pneumatically fed cigarette making machine comprises a chamber having an inlet for receiving a flow of tobacco carried by air, a curved deflector for deflecting the tobacco to a tobacco outlet, and an air outlet remote from the deflector, the deflector being movable (preferably pivotally) so that it can move from a first position, in which it deflects the tobacco to the tobacco outlet, to a second position in which it deflects the tobacco so that is passes out through a different'out le't (preferably the air outlet); from this last outlet the tobacco is preferably returned to the primary unit which delivers tobacco pneumatically to the air separator. This aspect of the invention can be applied to a separator such as that shown in British Pat. No. 1,192,177.

In use the deflector is preferably moved to its second position automatically when the cigarette making machine stops. Thus there is no need to arrange that the primary unit stops delivering tobacco as soon'as the making machine stops; the primary unit can instead go on delivering tobacco, which is returned by the'a'ir sep arator.

The air outlet of the separator may extend from the chamber in a direction transverse to the direction of motion of tobacco through the chamber. In thatcase, in order to deliver the tobacco out through the air outlet when the deflector moves to its second position, there may be a second deflector which, when the first deflector moves to its second position, moves to an operative position in which it deflects towards the air outlet the tobacco which is deflected past the tobacco outlet by the first deflector.

Examples of air separators according to this invention are shown in the accompanying drawings.

In these drawings:

FIG. 1 is a partly sectioned elevation of one separator;

FIG. 2 is a view in the direction of the arrow II in FIG. 1,'showing the air outlet in elevation; FIG. 3 is an enlarged fragmentary section on the line III--III in FIG. 1;

FIGS. 4 to 6 show how the cross-section of the deflector changes from one end to the other; and

FIGS. 7 and 8 show different separators.

As shown in FIG. 1, the air separator has an inlet pipe 2 of circular cross-section leading into an approximately cylindrical box 4. One end wall 4A (FIG. 2) is fitted with an air outlet pipe 6 which, at its end adjacent to the wall 4A, is coaxial with the circular peripheral wall of the box 4. Part of the peripheral wall of the box is formed by a deflector 8 which deflects the tobacco from the inlet 2 to a tobacco outlet 10. Most of the air (for example 80 to 90 percent) which carries the tobacco in through the inlet 2 is drawn 05 by suction through the outlet 6. However, some air passes out through the outlet 10 and into the inlet 12 of a spreading device in which there is a suction pressure sufficient to ensure that air flows outwards through the outlet 10 and into the separator. For example, the suction pressure in the box 4 may be mm water gauge, while there is a suction pressure of mm water gauge in the spreading device. The static suction pressure in the spreading device may be less than that in the box 4; however air does flow inwards through the outlet 10 on account of the dynamic pressure head in the box 4. Thus the tobacco moves out through the outlet 10 with out being retarded to any significant extent during its passage through the air separator. A high-speed knurled roller 13 is mounted at the tobacco outlet to force the tobacco through the outlet in the event of any momentary tendency for tobacco to jam in the outlet.

By way of example, the internal diameter of the pipe 2, and the internal distance between the

end walls

4A and 4B of the box 4, may be 76 mm. Air may pass through the inlet pipe 2 at a rate of 5 ,500 to 7,500 litres per minute and at a velocity of 21 metres per second to carry 6 to 9 kilograms per minute of tobacco to the spreading device of a cigarette making machine.

The pipe leading to the inlet pipe 2 is gently curved about horizontal axis below the pipe (assuming the separator is used with its tobacco outlet 10 extending vertically downwards) so that the tobacco is thrown outwards by centrifugal force. Thus the tobacco reaches the deflector 8 as a somewhat flat, wide, low-density stream 14 (see FIG. 1) lying against the part of the wall of the pipe 2 furthest from the axis of the box 4.

FIGS. 4 to 6 show how the internal cross-section of the deflector 8 changes in the direction of motion of the tobacco so as to convert the tobacco stream from a wide low-density form to a narrower and more dense stream which can pass out through the tobacco outlet 10.

On reaching the deflector, the tobacco stream 14 becomes thinner as it is compressed against the deflector by its own inertia. This thinner stream is then progressively bent into a V-shape (see FIG. 4) and then made narrower by the changing cross-section of the deflector.

FIG. 4 shows how the internal cross-section changes progressively from a semi-circular cross-section at A (corresponding to the outer half of the pipe 2) to a slightly rounded V-shape at B. FIG. 5 shows how the cross-section then changes progressively from the rounded V-shape at B to a narrower shape at C which includes a semi-circular bottom C. This semi-circular bottom shape then remains while the sides come together progressively towards the parallel states of the shape D shown in FIG. 6, which also shows the knurled roller 13.

Air which passes into the spreading device through the outlet 10 returns to the separator through a pipe 15 which directs the air axially into the box so that the air (together with any tobacco entrained in it) can pass straight through the box and into the outlet 6. This is helped by the fact that the outlet 6 includes a frustoconical end piece 6A (see FIG. 2).

As shown in FIG. 1, the deflector 8 is pivoted to the box at 16 so that it can be swung inwards, to the position shown in chain-dotted outline, to deflect the tobacco past the outlet 10. For this purpose the position of the deflector is controlled by an air cylinder 16A including a piston rod 18 which is pivoted to the deflector at 20. The air cylinder 16A moves the deflector 8 inwards automatically in response to a controller 17 when the cigarette machine is stopped, so that the delivery of tobacco to the separator by the primary unit does not have to be stopped.

At the same time as the deflector 8 is moved inwards, a second deflector 22 moves axially into the box 4 under the control of a second air cylinder 24 in response to the same controller 17. As shown in FIG. 3, the inner edge 22A of the deflector 22 normally lies just within a correspondingly curved slot in the end wall 48 of the box; the deflector is carried by a straight member 26 which in turn is carried by

posts

28 and 30 which can slide axially in

bearings

32 and 34. The air cylinder 24 includes a piston rod 25 which is connected to the member 26. when the deflector 22 moves into the box (to the position shown in chain-dotted outline) it forms a smooth continuation of a part 4C of the peripheral wall of the box. Thus tobacco moving along the wall part 4C, instead of continuing along the wall part 4!), is deflected inwards towards the air outlet 6. A deflector part 36 serves to deflect the tobacco axially into the outlet 6.

FIG. 7 shows diagrammatically a different separator which is similar to that shown in FIG. 1, except that instead of the axially moving deflector 22, a part 38 of the peripheral wall of the box is pivoted at 40 so that it can be moved inwards (for example by an air cylinder or other device) to the position shown in chain-dotted outline, so as to deflect the tobacco inwards towards the air outlet 41. A curved part 38A forms a seal with the edge 43 of the peripheral wall of the box.

FIG. 8 shows a separator which is basically similar to that shown in FIG. 1, except that the axial air outlet is replaced by a tangential outlet 42 which starts with a rectangular cross-section so that it has a flat outer wall 44 which forms a tangential extension to the peripheral wall of the box from the point 46. Thus when the deflector 48 moves inwards to carry the tobacco stream past the outlet 50, the tobacco stream automatically passes out through the air outlet 42.

I claim:

1. Apparatus for pneumatically feeding tobacco to a cigarette making machine, including an air separator comprising a chamber having an inlet of given crosssectional area for receiving a flow of tobacco carried by air, a deflector which deflects the tobacco along a curved path towards a tobacco outlet, and an air outlet remote from the deflector, the tobacco outlet having a smaller cross-sectional area than the inlet, and the deflector being so shaped that it progressively reduces the transverse dimensions of the tobacco stream with the aid of centrifugal force to enable the tobacco to pass out through the tobacco outlet.

2. Apparatus according to claim 1 in which the inlet to the chamber is of circular cross-section and in which the cross-sectional shape of the deflector changes progressively from a semi-circular shape, which corresponds to half the inlet section, through a substantially V-shaped cross-section, to a narrow trough-shaped cross-section with a semi-circular bottom of smaller radius than the inlet.

3. Apparatus according to claim 2 including a knurled roller which extends into the narrow troughshaped part of the deflector and is driven in a direction such as to help to drive tobacco out through the tobacco outlet in the event of a tendency for tobacco to jam at the outlet.

4. Apparatus according to claim 1 in which at least part of the deflector is movable to a second position in which it deflects the tobacco so that it passes out through a different outlet.

5. Apparatus according to claim 4 in which the deflector is pivotally movable about an axis adjacent to the inlet.

6. Apparatus according to claim 4 in which, when the deflector is in its second position, the tobacco passes out through the air outlet.

7. A cigarette making system according to claim 4, and including means for automatically moving the deflector to its second position in response to a signal.

8. Apparatus according to claim 1 in which the air outlet extends from the chamger in a direction transverse to the direction of motion of tobacco through the chamber.

9. Apparatus according to claim 8, including a second deflector which, when the first deflector is moved to its second position, can be moved to a position in which it deflects the tobacco into the air outlet.

10. Apparatus according to claim 9 in which the second deflector moves linearly into the chamber in a direction transverse to the direction of motion of the tobacco through the chamber,

11. Apparatus for pneumatically feeding tobacco to a cigarette making machine, including an air separator comprising a chamber having an inlet for receiving a flow of tobacco carried by air, a curved deflector for deflecting the tobacco to a tobacco outlet, and an air passes out through the air outlet.

Claims

1. Apparatus for pneumatically feeding tobacco to a cigarette making machine, including an air separator comprising a chamber having an inlet of given cross-sectional area for receiving a flow of tobacco carried by air, a deflector which deflects the tobacco along a curved path towards a tobacco outlet, and an air outlet remote from the deflector, the tobacco outlet having a smaller cross-sectional area than the inlet, and the deflector being so shaped that it progressively reduces the transverse dimensions of the tobacco stream with the aid of centrifugal force to enable the tobacco to pass out through the tobacco outlet.

3. Apparatus according to claim 2 including a knurled roller which extends into the narrow trough-shaped part of the deflector and is driven in a direction such as to help to drive tobacco out through the tobacco outlet in the event of a tendency for tobacco to jam at the outlet.

10. Apparatus according to claim 9 in which the second deflector moves linearly into the chamber in a direction transverse to the direction of motion of the tobacco through the chamber.

11. Apparatus for pneumatically feeding tobacco to a cigarette making machine, including an air separator comprising a chamber having an inlet for receiving a flow of tobacco carried by air, a curved deflector for deflecting the tobacco to a tobacco outlet, and an air outlet remote from the tobacco outlet, the deflector being movable so that it can move from a first position, in which it deflects the tobacco to the tobacco outlet, to a second position in which it deflects the tobacco so that it passes out through a different outlet.

12. Apparatus according to claim 11 in which the deflector is pivotally movable about an axis adjacent to the inlet.

13. Apparatus according to claim 11 in which, when the deflector is in its second position, the tobacco passes out through the air outlet.