GB2296420A

GB2296420A - Cigarette making machine

Info

Publication number: GB2296420A
Application number: GB9525813A
Authority: GB
Inventors: John Dawson; Derek Henry Dyett
Original assignee: Molins Ltd
Current assignee: Mpac Group PLC
Priority date: 1994-12-24
Filing date: 1995-12-18
Publication date: 1996-07-03
Anticipated expiration: 2015-12-18
Also published as: ITRM950842A1; GB9525813D0; IT1277957B1; GB9426249D0; ITRM950842A0; GB2296420B

Abstract

The machine includes a shower channel (10) through which tobacco is conveyed upwards pneumatically to form a cigarette filler stream on a suction band (12) running along the top of the shower channel, the tobacco being directed towards the lower end of the shower channel by being projected approximately horizontally over a jet block (22) through which air flows are induced to deflect the tobacco upwards and into the channel, the air flow passages (34, 36) in the jet block being inclined to the vertical so as to impart a horizontal component of movement to the tobacco particles in the general direction of movement of the suction band. <IMAGE>

Description

Cigarette Making Machine This invention is concerned with cigarette making machines of the type in which tobacco is showered pneumatically up a channel extending towards a suction band on which the tobacco accumulates to form a cigarette filler stream. Examples of machines of this type are described in our British patents 934816 and 971736. Some specific machines to which this principle has been applied are the Molins Mark 8 and Mark 9 machines.

This invention is particularly concerned with an improvement in a machine of the type described in patent 971736, in which tobacco enters the lower end of the shower channel after passing around a perforated cylinder which communicates with a source of suction to draw air upwards through the tobacco via passages in a member below the cylinder, commonly referred to as a "jet block". The jets of air induced through the passages deflect lighter particles of tobacco upwards so that they enter the shower channel while heavier particles and pieces of tobacco stem continue along an approximately horizontal trajectory and commonly enter a winnower. In the winnower, lighter particles of tobacco entrained with the heavier particles are removed and are directed upwards into the shower channel.

We have found it desirable to incline the centre line of the shower channel to the vertical so that showered tobacco arrives on the suction band with a component of movement in the direction of movement of the band. For this purpose, it is possible in principle to deflect the particles of tobacco, as they enter the shower channel, by means of a separate flow of air passing through guide vanes for directing the air into the shower channel in directions inclined to the vertical so as to impart the desired forward component to the tobacco particles.

According to the present invention, the tobacco particles, as they pass over the jet block, are given a horizontal component of movement by virtue of the passages in the jet block being inclined to the vertical.

We have found that this produces a more even flow of tobacco particles up the shower channel in substantially parallel directions which may, for example, be at an angle of 40 to the vertical.

An example of a machine according to this invention is shown in the accompanying drawings. In these drawings: Figure 1 is a diagrammatic front view of the machine as a whole; Figure 2 is an end view of the winnowing section of the machine on a larger scale; Figure 3 is a plan view of one end of the jet block on an even larger scale; and Figure 4 is a section on the line IV-IV in Figure 3.

Figure 1 shows the general arrangement of the cigarette making machine, comprising an upwardly extending shower channel or "chimney" 10 through which tobacco is showered towards a suction band 12 to form a cigarette filler stream. A trimming device 14 operates on the filler stream to remove part of the filler stream and thus make the remainder more uniform, and the trimmed filler stream is then delivered into a conventional garniture in which a continuous wrapper web 16 is sealed around the filler stream to form a continuous cigarette rod.

It will be seen that the centre line of the chimney 10 is inclined to the vertical by about 40 . Accordingly, it is desirable to introduce tobacco into the lower end of the chimney, not in a vertical direction, but at the corresponding 40O inclination.

As described in our patent 971736, tobacco is metered by a hopper including a carded drum (not shown) from which the tobacco is removed by a picker roller and is then projected by means of a winnower roller along a guide surface 18 shown in Figure 2. After passing a downward step 20, the tobacco is airborne and is then deflected upwards by air jets flowing through upwardly extending passages in a jet block 22 which is shown in greater detail in Figures 3 and 4. Some of the air introduced through the jet block passes up the chimney 10, and the remainder of the air flows into a rotating perforated cylinder 24 of which the interior is connected to a source of suction.

Lighter particles of tobacco are deflected upwards by the air jets and are also given a horizontal component of motion by virtue of the fact that the passages in the jet block 22 are inclined to the vertical by the angle A (see Figure 4),which is approximately 40 . Heavier particles of tobacco and pieces of stem and the like (together with some entrained lighter particles of tobacco) continue in an approximately horizontal trajectory across the jet block 22 and drop into a downwardly extending duct 26. At the bottom of this duct there is a roller (not shown) of which one of the end bearings 28 is shown, and this roller rotates in an anti-clockwise direction to deliver the heavier tobacco into a further duct 30. Air passes up the duct 30 and separates lighter particles of tobacco from pieces of stem and the like, which drop to the bottom of the duct 30 and are removed. The lighter particles of tobacco are carried upwards by the air flow and into a channel 32 leading to the lower end of the chimney 10.

As shown particularly in Figures 3 and 4, the jet block has seven rows of parallel passages 34 of circular cross-section, and two rows of slightly inclined passages 36. The passages in adjacent rows are staggered so that the passages can be positioned close together.

It is also important to ensure, by appropriate design of the air flow passages, that the suction level is uniform across the top of the chimney 10, is uniform in the cylinder 24 and is uniform across the top of the jet block 22.

Claims

Claims:

1. A cigarette making machine including a shower channel through which tobacco is conveyed upwards pneumatically to form a cigarette filler stream on a suction band running along the top of the shower channel, the tobacco being directed towards the lower end of the shower channel by being projected approximately horizontally over a jet block through which air flows are induced to deflect the tobacco upwards and into the channel, the air flow passages in the jet block being inclined to the vertical so as to impart a horizontal component of movement to the tobacco particles in the general direction of movement of the suction band.

2. A cigarette making machine according to claim 1, including a perforated cylinder mounted for rotation above the jet block and around which the tobacco particles pass as they move towards and into the lower end of the channel the interior of the cylinder being in communication with a suction source whereby at least part of the air flow through the jet block is induced.

3. A machine according to claim 1 or claim 2, in which heavier particles of tobacco which are not deflected into the channel by the air flowing through the jet block pass to a winnowing arrangement in which lighter particles of tobacco entrained with the heavier particles are separated and then carried pneumatically up into the channel via a further flow passage.

4. A machine according to claim 1 and substantially as described with reference to the accompanying drawings.