GB2034577A - Cigarette handling apparatus - Google Patents

Abstract

Apparatus for handling cigarettes, having a rotatable drum 5 formed with flutes 6 along which cigarettes A are moved axially. A nylon band 7 is draped helically around the drum and is driven at such a speed that there is a purely axial motion relative to the drum. Rounded teeth 9 formed in the side of the band 7 engage the cigarettes A to displace them accurately and gently the required distance along the flutes. <IMAGE>

Description

SPECIFICATION Cigarette handling apparatus This invention relates to apparatus for handling rod-like articles, in particular cigarettes; and for convenience all such articles will hereafter simple be referred to as cigarettes.

In the high speed manufacture of cigarettes on continuous rod machines it becomes difficult to produce cigarettes having good square-cut ends.

This is due to the speed limitations of known cut-off and ledger mechanisms. In British Patent Specification No. 1,371,046 it is proposed to overcome this difficulty by taking advantage of the excellent cuts which can be produced by moving cigarettes laterally past a rotating disc knife: in that proposal a continuous rod is severed by the cut-off into double length rods, which are then moved laterally and cut into two rows of individual cigarettes by the disc knife. The relative positions of the two rows are next reversed so that the good ends of the cigarettes are facing outermost; and finally filter plugs are attached by encircling bands to the innermost ends of the cigarettes which have been severed by the cut-off. By this method the relatively poor ends produced by the cut-off are concealed by the encircling bands, while the opposite exposed ends are of high quality.The apparatus disclosed in the above mentioned specification comprises a first fluted drum for receiving the double lengths rods from the cut-off and on which the rods are severed into two rows of individual cigarettes by the disc knife, a second fluted drum onto which one of the row is transferred and having a stop in each flute, displacing means in the form of air jets to displace the cigarettes of said row axially along the flutes until they meet the stops, and means to transfer the displaced cigarettes back to the first drum at the opposite side of the other row in readiness for filter plugs to be attached between the innermost ends of the rearranged rows.

However it is now considered that the displacement of the cigarettes along the flutes of the second drum by means of air jets may be disadvantageous, as it may cause the good ends of the cigarettes to be damaged against the stops in the flutes; furthermore this action is indefinite in that an accurate and gentle displacement of the cigarettes towards the stops is difficult to achieve.

As an alternative it was proposed in the above mentioned specification to displace the cigarettes either by suction or by engaging the ends of the cigarettes against a fixed helical guide. However it is believed that neither of these solutions satisfactorily overcomes the above mentioned disadvantages.

According to the present invention a continuous band is draped in the shape of a helix around at least part of the second drum and is rotatable therewith to move the cigarettes axially along the flutes, the velocity and helical angle of the band being such that the peripheral velocity of the drum is equal to the velocity component of the band in the direction of rotation of the drum.

In this way there is a purely axial relative motion between the band and the fluted drum, which band can thus accurately and gently displace the cigarettes the required distance along the flutes.

The band may be made from a solid nylon material; and it is preferably formed at one side with regularly spaced rounded teeth to engage the ends of the cigarettes. A toothed driving roller may be disposed at the exit of the band from said helix around the drum, to engage with corresponding indentations (or alternatively protuberances) formed on the band. A similar slave roller may be disposed at the entrance of the band to said helix and driven so that the band is held sufficiently slack around the drum. Upstream of said slave roller there may be at least two turner bars to re-orient the bands towards the entrance of said helix.

An example of cigarette handling apparatus according to the invention will now be described with reference to the accompanying drawings: Figure 1 is an end elevation of the apparatus, Figure 2 is a front elevation of the lower fluted drum shown in Figure 1, and Figure 3 is a developed view of the fluted drum of Figure 2.

Referring first to Figure 1, there is shown a catcher drum 1 of a continuous rod cigarette making machine, which receives a double length cigarette rod D in each of its flutes 2 from the cut-off mechanism (not shown) of the cigarette making machine. The double length rods Dare held in their flutes 2 by suction applied to radial drillings 3 in the drum 1. As the rods rotate with the drum in a clockwise direction they pass a rotary disc knife 4 which divides each into two individual cigarette lengths, resulting in two rows of cigarettes A and B, the cigarettes A being in front of cigarettes B as viewed in Figure 1.

Beneath drum lisa fluted drum 5 similar to the drum 1 but slightly longer axially. The drum 5 rotates anticlockwise and has thirteen flutes 6 which successively register with the flutes 2 to receive the cigarettes A from the drum 1. While rotating with the drum the cigarettes A are displaced along the flutes 6 by a moving band 7, to be described in greater detail below. After one revolution each cigarette A has been displaced a distance somewhat greater than two cigarette lengths, and it is then transferred back to the drum 1 at the other side of the cigarettes B, but thirteen spacings behind the cigarette B from which it was severed. The cigarettes B and A (the cigarettes B being now in front of the cigarettes A as viewed in Figure 1) are then transferred to a further fluted drum 8 where filter mouthpieces are attached to the cigarettes in a known manner.

While travelling on the drum 5, the cigarettes A are held in the flutes 6 by light suction applied through radial drillings 9 in the drum. Additionally, or in place thereof, the cigarettes A are prevented from falling out of the flutes 6 by a shroud 18 extending helically around the drum.

Referring now also to Figures 2 and 3, the belt 7 passes around the drum 5 in the form of a helix, extending around just over 3/4 of the periphery of the drum 5. As best seen in the developed view of Figure 3, the left side of the belt is provided with slightly rounded teeth 9 formed at regular intervals corresponding to the pitch between the flutes 6.

Outside the drum 5 the belt passes over a drive roller 10, an idler 11, a pair of stationary turner bars 12, a further idler 13, and a slave drive roller 14. The roilers 10, 14 are formed with driving teeth 15 which engage with identations 16 in the band 7. The relative angular positions of the rollers 10, 14 can be so adjusted as to enable the band to be held at a controlled slackness (e.g. at an average of about 0.2 mm) away from the periphery of the drum 5.

The driven velocity of the band 7 is so related to the peripheral velocity Vd of the drum that the latter is equal to the component of the velocity of the band in the direction of the drum (see Figure 3). This condition is satisfied by the equation Vd = Vb Cos h, where h is the helix angle of the band. Therefore the band 9 will move relative to the drum at a velocity component Vc which is purely axial of the drum, so that each tooth 9 as it moves round the drum remains in alignment with a respective flute 6 of the drum.

Thus in use after a cigarette A has been received in a flute 6 it is engaged by a tooth 9 of the belt, which progressively displaces it to the left, as viewed in Figure 3, until it isfartherto the left than the cigarettes B. Then as each flute 6 reaches the uppermost position of the drum 5, the cigarette A in that flute is transferred back to the drum 1 by suction applied to the lowermost flute 2 thereof, assisted by a puff of air applied at 17 to the flute 6.

The band 7 may be made from a solid nylon material of about 3 or 4 mm thick, and the teeth 9 and indentations 16 may be moulded in the band in the course of its manufacture.

Claims (3)

1. Apparatus for handling cigarettes comprising a rotatable drum formed with flutes each for receiv ing a cigarette, the length of each flute being greater than the length of a cigarette, a continuous band draped in the shape of a helix around at least part of said drum and rotatable therewith to move the cigarettes axially along the flutes, the velocity and helical angle of the band being such that the peripheral velocity of the drum is equal to the velocity component of the band in the direction of rotation of the drum.

2. Apparatus as claimed in claim 1 in which said band is made from a solid nylon material, and is formed with regularly spaced rounded teeth at the side which is engageable with the ends of the cigarettes.

3. Apparatus substantially as herein described with reference to, and as described in, Figures 1 to 3 of the accompanying drawings.