GB1565206A - Suction conveyor drums for cigarettes and similar rodlike articles - Google Patents

Description

(54) IMPROVEMENTS RELATING TO SUCTION CONVEYOR DRUMS FOR CIGARETTES AND SIMILAR ROD-LIKE ARTICLES (71) We, MOLINS LIMITED, a British company, of 2, Evelyn Street, Deptford, London, SE8 5DH, do hereby declare the invention for which we pray that a patent may be granted to us, and the method by which it is to be performed, to be particularly described in and by the following statement: In filter-attachment machines used in the manufacture of filter-tipped cigarettes there are commonly several fluted drums which convey cigarettes and/or filter rods or complete assemblies by means of suction applied through ports opening out in the flutes.

Within each drum there is usually a sleeve valve which has slots through which suction within the sleeve valve is transmitted to the ports where necessary. In the region where the fluted drum is not carrying rods. provision is sometimes made for compressed air to be blown out through the ports from a pressure manifold which is within or part of the sleeve valve.

The present invention is concerned with an improved arrangement for cleaning the ports.

According to the present invention, a fluted drum for conveying cigarettes or similar rod-like articles by means of suction has a row of suction ports in each flute, each port lying in a plane normal to the axis of the drum in which one port in each of a number of other flutes also lies; and the drum contains a sleeve valve in one side of which, where the drum is not arranged to carry rods, there is a compressed air channel which is approximately parallel to the axis of the drum and has a number of air supply apertures each of which lies in one of the planes containing the suction ports, the apertures being staggered circumferentially (preferably with respect to a rotating tube within the channel) so that the suction ports which are in different ones of the planes do not all receive compressed air at the same time.

This invention allows for more reliable clearance of obstructing matter from the suction ports without requiring very high pressure or a large air flow. In the previous system a relatively large air flow was needed at a relatively high pressure to ensure that the air did not tend to take the easy route out of the compressed air manifold, i.e.

through the unobstructed ports.

In a preferred arrangement, the compressed air channel comprises a bore which is parallel to the axis of the drum and which contains a tube of which the wall has a number of circumferentially staggered aper-.

tures. the tube being supplied with compressed air and being rotatable, and each of the apertures in the tube lying in one of the planes containing one of the suction ports for each flute. the arrangement being such that some of the apertures in the tube are closed at all times by the wall of the bore in the sleeve valve while at least one (and not more than a few) discharge a jet of air into one circumferentially extending row of suction ports. Alternatively. the compressed air channel itself could be inclined slightly to a line parallel to the axis of the drum, the air supply apertures being formed as fixed radial apertures leading from the channel to the outer surface of the sleeve valve.

An example of a fluted drum according to this invention is shown in the accompanying drawings. In these drawings: Figure 1 is a partly cut away side elevation of the drum; and Figure 2 is a section on the line II-II in Figure 1, showing also parts of adjacent rod conveying drums.

As shown in Figure 2, a fluted drum 10 receives completed filter-tipped cigarettes (or other similar rodlike articles) 12 from a drum 14 and then delivers the cigarettes to a fluted drum 16. The drum 10 has axially extending flutes 10A in which the cigarettes are carried by means of suction applied through ports 10B. As shown in Figure 1, each port 10B lies in a plane normal to the axis of the drum which contains one port from each of the other flutes; that is to say the ports lie in circumferential rows.

Suction is transmitted to the ports 10B from the space 18 through a number of slots 20A in a stationary sleeve valve 20 mounted within the drum 10. By this means, suction is applied to the ports 10B where necessary to hold the cigarettes on the drum, but not elsewhere; On a side of the sleeve valve where no cigarettes are being carried by the drum, there is an axial bore in a thickened part 20B of the wall of the sleeve valve. The bore is positioned so as to leave a narrow slot 20C in the outer surface of the sleeve valve. A tube 22 is rotatably mounted in the bore, being rotatable continuously or from time to time by means of a knurled knob or gear wheel 24, (i.e. either manually or by a mechanical drive). Compressed air is supplied into one end of the tube 22, the other end of the tube being closed.

The wall of the tube 22 is formed with a row of apertures 26 lying on a helical line. as shown in Figure 1. The helix could comprise a single turn so that only one aperture at a time is able to discharge a jet of compressed air through the slot 20C in the sleeve valve.

Alternatively, the helix pitch could be smaller so that the hexis comprises two or three turns, in which case two or three jets are discharged at the same time. The drawings show one aperture 26A in position to discharge a jet of compressed air through one circumferentially extending row of the ports 10B.

Instead of the apertures 26 lying on a helical line, they could be arranged in a random fashion so that only one at a time (or possibly two or three) is aligned with the slot 20C in the sleeve valve.

WHAT WE CLAIM IS: 1. A fluted drum for conveying cigarettes or similar rod-like articles by means of suction, having a row of suction ports in each flute. each port lying in a plane normal to the axis of the drum in which one port in each of a number of other flutes also lies: and the drum contains a sleeve valve in one side of which where the drum is not arranged to carry rods there is a compressed air channel which is approximately parallel to the axis of the drum and has a number of air supply apertures each of which lies in one of the planes containing the suction ports, the apertures being staggered circumferentially so that suction ports which are in different ones of the planes do not all receive compressed air at the same time.

2. A fluted drum according to claim 1 in which the compressed air channel comprises a bore which is parallel to the axis of the drum and which contains a tube of which the wall has number of circumferentially staggered apertures, the tube being supplied with compressed air and being rotatable, and each of the apertures in the tube lying in one of the planes containing one of the suction ports for each flute, the arrangement being such that some of the apertures in the tube are closed at all times by the wall of the bore in the sleeve valve while at least one (and not more than a few) discharge a jet of air into one circumferentially extending row of suction ports.

3. A fluted drum according to claim 2 including drive means for rotating the tube continuously or from time to time.

4. A fluted drum according to claim 2 or claim 3 in which the apertures in the tube lie substantially along a helix.

5. A fluted drum according to any one of claims 2 to 4 in which the sleeve valve is formed with a narrow slot through which air jets are discharged from the apertures in the tube.

6. A fluted drum according to claim 1 and substantially as described with reference to the accompanying drawings.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (6)

**WARNING** start of CLMS field may overlap end of DESC **. are carried by means of suction applied through ports 10B. As shown in Figure 1, each port 10B lies in a plane normal to the axis of the drum which contains one port from each of the other flutes; that is to say the ports lie in circumferential rows. Suction is transmitted to the ports 10B from the space 18 through a number of slots 20A in a stationary sleeve valve 20 mounted within the drum 10. By this means, suction is applied to the ports 10B where necessary to hold the cigarettes on the drum, but not elsewhere; On a side of the sleeve valve where no cigarettes are being carried by the drum, there is an axial bore in a thickened part 20B of the wall of the sleeve valve. The bore is positioned so as to leave a narrow slot 20C in the outer surface of the sleeve valve. A tube 22 is rotatably mounted in the bore, being rotatable continuously or from time to time by means of a knurled knob or gear wheel 24, (i.e. either manually or by a mechanical drive). Compressed air is supplied into one end of the tube 22, the other end of the tube being closed. The wall of the tube 22 is formed with a row of apertures 26 lying on a helical line. as shown in Figure 1. The helix could comprise a single turn so that only one aperture at a time is able to discharge a jet of compressed air through the slot 20C in the sleeve valve. Alternatively, the helix pitch could be smaller so that the hexis comprises two or three turns, in which case two or three jets are discharged at the same time. The drawings show one aperture 26A in position to discharge a jet of compressed air through one circumferentially extending row of the ports 10B. Instead of the apertures 26 lying on a helical line, they could be arranged in a random fashion so that only one at a time (or possibly two or three) is aligned with the slot 20C in the sleeve valve. WHAT WE CLAIM IS:

1. A fluted drum for conveying cigarettes or similar rod-like articles by means of suction, having a row of suction ports in each flute. each port lying in a plane normal to the axis of the drum in which one port in each of a number of other flutes also lies: and the drum contains a sleeve valve in one side of which where the drum is not arranged to carry rods there is a compressed air channel which is approximately parallel to the axis of the drum and has a number of air supply apertures each of which lies in one of the planes containing the suction ports, the apertures being staggered circumferentially so that suction ports which are in different ones of the planes do not all receive compressed air at the same time.

2. A fluted drum according to claim 1 in which the compressed air channel comprises a bore which is parallel to the axis of the drum and which contains a tube of which the wall has number of circumferentially staggered apertures, the tube being supplied with compressed air and being rotatable, and each of the apertures in the tube lying in one of the planes containing one of the suction ports for each flute, the arrangement being such that some of the apertures in the tube are closed at all times by the wall of the bore in the sleeve valve while at least one (and not more than a few) discharge a jet of air into one circumferentially extending row of suction ports.

3. A fluted drum according to claim 2 including drive means for rotating the tube continuously or from time to time.

4. A fluted drum according to claim 2 or claim 3 in which the apertures in the tube lie substantially along a helix.

5. A fluted drum according to any one of claims 2 to 4 in which the sleeve valve is formed with a narrow slot through which air jets are discharged from the apertures in the tube.

6. A fluted drum according to claim 1 and substantially as described with reference to the accompanying drawings.