Abstract: Air is blown into filter tow during or immediately after the application of plasticizer; this foams and distributes the plasticizer in the tow. Air may be delivered from a porous plate closely adjacent to the path of the tow or from nozzles in an air injecting unit. Alternatively air may be used to foam plasticizer at a location remote from the tow and foamed plasticizer subsequently conveyed to and into the tow by a roller.

Abstract: A slicing machines includes a control system having a camera (6) which views a cut face (5) of a product being sliced. Image data from the camera (6) is processed to determined a parameter characteristic of the cut face (5). The step of processing the image data includes classifying the image data by comparison with an intensity threshold which is varied automatically in accordance with the populations of data in the different classes. A control signal is generated to control the operation of the slicing machine in accordance with the determined parameter.In a preferred example, the determined parameter depends on the linear density of the cut face and the control signal varies the thickness of the slices in order to produce a slice having a desired weight.

Abstract: Laser perforation apparatus for filter cigarettes includes a drum (10) for conveying cigarettes (11), bands (33, 34) for slowly rotating each cigarette as it is conveyed by the drum, and a laser beam deflector (21, 22) carried by a tubular member (19) coaxially and rotatably mounted relative to the drum, the tubular member being rotated at relatively high speed and the laser being pulsed so that successive pulses are directed by the deflector towards successive cigarettes and each cigarette thus has a number of perforations formed in its wrapper as it is conveyed between the drum and the bands.

Abstract: A slicing machine for cutting slices from a product includes a camera (6) which views a cut face (5) of the product. A boundary recognition processor (14) processes image signals from the camera (6) to determine a boundary of the cut face (5). A parameter characteristic of the cut face (5) is calculated from image data corresponding to regions of the cut face within the determined boundary. A control signal generating circuit generates a control signal to control the operation of the slicer in accordance with the determined parameter.In a preferred example, the boundary is analysed to determine the location of any secondary regions (10) of the cut face (5) and the characteristic parameter is calculated from image data corresponding to regions of the cut face other than the secondary regions.

Abstract: Cigarette tipping paper is perforated by a laser 31 emitting a beam which is directed onto the tipping paper via an acousto-optical beam deflector 33 and a beam splitter 34 producing two parallel perforation tracks 24 along the tipping paper. Each track may include a number of rows of perforations, the laser beam being deflected for that purpose by the acousto-optical device. The porosity of the tipping paper and/or the dilution of the completed cigarettes can be controlled in various ways, particularly by the use of an acousto-optical device; the latter may be used to vary the perforation pattern, the laser beam being directed onto a heat sink 52 when it is not required to perforate the tipping paper. Control of the perforation pattern, as well as allowing different patterns to be applied, is used to control the dilution factor of the finished cigarettes.

Abstract: A rod cut-off in a cigarette making machine includes a cutting device 32 having a first drive 34, a ledger 10 for supporting the rod during cutting and having a second drive 22, separate from the first drive, a device for synchronizing (prefereably electronically) the first and second drives during normal operation, and a device 40 for mechanically displacing the ledger or cutting device (preferably the former) from the normal position in which it co-operates with the other member to perform rod cutting, the displacement being arranged to occur while the machine is being accelerated from start; that is, during the time while the two drives are being brough into synchronization.

Abstract: Cigarettes are perforated by being rolled along a row of pins which are excited, for example by being vibrated. Vibration may be towards and away from the cigarettes so that the pins penetrate as a result of the vibration; the depth of penetration may be varied to control the size of the perforations. Alternatively the vibration may be in a direction transverse to the axes of the pins. In either case the pins may be mounted on a flexible member having a resonant frequency equal to the frequency of vibration. The vibratorary drive may be an electro magnetic device or a piexoelectric crystal. An alternative form of excitation of the pins involves passing compressed air through the pins and into the cigarettes, the pins being tubular for that purpose.

Abstract: In the production of cigarette filter rod from filter tow the conveyance of tow into a tow shaping unit (12, 32, 56, 76) is aided by controlling tow tension so that excessive stretch (and hence possible loss of crimp) is avoided. The tension is controlled by two conveying arrangements upstream of the tow shaping unit and which may include air extracting devices and entraining devices (20-28), opposed tow engaging wheels (34, 36), a tow reservoir (64), a tow engaging refuser roller (70), or a tow spinning unit (74). In the tow spinning unit (74) the tow is gathered ad twisted in a converging conical guide which is rotated at high speed, and which may also impart an axial thrust to the tow to aid conveyance into the tow shaping unit (76).

Abstract: Apparatus for applying fluid additive to a stream of fibrous material such as a filter tow. The apparatus provides structure for blowing air into the filter tow during or immediately after the application of the fluid additive, a plasticiser; this foams and distributes the plasticiser in the tow. Air may be delivered from a porous plate closely adjacent to the path of the tow or from nozzles in an air injecting unit. Alternatively air may be used to foam plasticiser at a location remote from the tow and foamed plasticiser subsequently conveyed to and into the tow by a roller.

Abstract: In apparatus for conditioning filter tow for subsequent production of cigarette filter rod a stream of filter tow is conveyed from a source by a first drive unit which delivers the tow into a conditioning station. A second drive unit delivers the conditioned tow to a rod-forming unit. A variable speed transmission is provided to allow independent control of the first and second drive units. The transmission may be replaced by an electronic speed control arrangement.

Abstract: Plasticizer or other fluid additive is applied to a moving filter tow in an applicator chamber by means of a rotary brush. Uncaptured plasticizer is collected in a container and returned to the chamber for reapplication. The rate of initial application is controlled by a pump and that of reapplication by a restrictor valve; the rates are independently variable. The supplied and collected plasticizer may be applied to different parts of the tow, e.g. to different sides.

Abstract: In the manufacture of filter rods for the tobacco industry, plasticizer and one or more flavorants or other additives are mixed in controlled proportions in a mixing chamber (100) in a tow opening machine. This allows different flavorant mixes to be made at the machine and avoids problems with mixes that separate or have short shelf lives.

Abstract: Production of cigarette filter rod is controlled by monitoring the tow (12) or rod (18) to provide signals indicative of tow consumption rate and varying the composition of the rod in accordance with the signals, e.g. to maintain a constant proportion by weight in the rod of tow and a plasticizer applied to the tow by an applicator device (18). The tow feed rate or the plasticizer supply rate may be varied in accordance with the signals. The monitoring device may comprise a tow bale weight sensor (48), a rod scanning head (54), or a weight band (33,57).

Abstract: Apparatus for treating filter material, particularly a filter tow for forming into a cigarette filter rod, includes an applicator chamber containing a rotatable brush for spraying a fluid additive such as a plasticizer towards the tow. A pressure manifold having a permeable surface adjacent the path of the tow produces an air flow which redirects towards the tow of plasticizer not captured initially by the tow. Air supplied to the manifold passes through an air ionization region, to reduce static electricity in the chamber. Air is withdrawn from the chamber by a pump to prevent a pressure build-up which could cause loss of uncaptured plasticizer. A separator is provided for collecting any plasticizer entrained with the extracted air and for returning it to a supply tank.

Abstract: The application of fluid additive to a moving filter tow for production of filter rod for cigarettes, is controlled by a system which provides monitoring of rate of application of the additive by weight. Fluid additive, such as plasticizer, is pumped from a measuring cylinder to an applicator booth, excess additive draining back to the cylinder. Pressure in the cylinder is monitored by a transducer and a control circuit is provided to compare the rate of loss of additive from the cylinder (as measured by change in pressure) with a required value and adjust the supply pump by way of a motor and gearbox accordingly. Fluid additive is periodically supplied to the cylinder from a flask and reservoir.

Abstract: Apparatus for determining the height of a column of tobacco or similar particulate material in a downwardly extending channel, comprising a first capacitor, a second capacitor formed partly by an electrode plate extending above and below the desired average level of the top surface of the tobacco column in the channel during use, a third capacitor formed partly by an electrode plate lying permanently below the top surface of the tobacco column, and an electrical circuit which compares the value of the second capacitor with the sum of the values of the first and third capacitors and from which output signal can be obtained which reflects that comparison.