Abstract: The carding at the periphery of a driven wheel in the distributor of a cigarette rod making machine receives tobacco particles from the lower portion of a substantially upright duct the upper portion of which can receive tobacco particles from a magazine by way of an elevator conveyor. At least the lower portion of the duct is vibrated (e.g., at an amplitude of approximately 6 mm and at a frequency of 15-25 Hertz) in directions at right angles to the horizontal rotational axis of the wheel to thus enhance the homogeneousness of the carpet of particles being transported by the carding beyond the discharge end of the lower portion of the duct.

Abstract: The diameters of successive rod-shaped articles of the tobacco processing industry are ascertained while the articles advance in the flutes of a conveyor, first along a rolling unit which turns successive articles at random through different angles and thereupon past a photoelectronic detector wherein a radiation source emits a narrow beam of radiation which impinges upon successive articles for intervals of time which are dependent upon the diameters of the articles. The transducer of the detector generates signals which are indicative of the monitored diameters, and such signals are transmitted to an evaluating circuit which controls an ejector for unsatisfactory articles and/or displays the monitored diameters on a screen. The articles are partially lifted off the conveyor by cushions of compressed air during transport past the rolling unit.

Abstract: The density of a tobacco stream which is advanced by a foraminous conveyor toward the surplus removing station of a cigarette rod making machine is measured by one or more detectors each having one or more sources of infrared light and one or more photoelectric transducers. In order to avoid the generation of distorted signals in response to impingement of high-intensity radiation upon the transducer or transducers, each transducer is out of line with the path of direct propagation of radiation from the respective source or sources toward successive increments of the tobacco stream. The transducer or transducers receive infrared light which is scattered in and/or reflected by tobacco particles in the stream. Signals from the transducer or transducers are used to regulate the quantity of surplus which is removed from the stream.

Abstract: A stream of tobacco fibers is formed in a channel by showering the fibers against the underside of the lower reach of a foraminous belt conveyor which cooperates with a suction chamber to attract the fibers and to advance the stream past a trimming station where the surplus of fibers is removed by an adjustable equalizing device. The density of the stream is monitored upstream of the trimming station, and the thus obtained signals which are indicative of the density of successive increments of the stream are used to adjust the equalizing device so that the density of the trimmed stream is maintained within a desired range. Monitoring of density upstream of the trimming station ensures that the position of the equalizing device is properly adjusted not later than when the monitored increments of the stream reach the trimming station.

Abstract: A continuous filter tow is advanced through a combined wrapping and condensing station by an endless belt, and the thickness of the belt decreases as a result of wear. The resistance which the condensed tow offers to the flow of air is measured by a pneumatic detector at the aforementioned station, and the accuracy of such measurement is affected by decreasing thickness of the belt as a result of increasing rate of escape of testing fluid along the belt. Therefore, the thickness of the belt is monitored and signals which are generated to denote the thickness of the belt are used to correct signals which are generated to denote the resistance to the flow of air. The correction involves modifying the signals denoting the resistance to the flow of air to denote a more pronounced resistance proportionally with decreasing thickness of the belt.

Abstract: Apparatus for making perforations in a running web of wrapping material for tobacco or filter rods or in the wrappers of discrete cigarettes has a carbon dioxide laser with two parallel resonators which are mechanically coupled to each other to define a U-shaped resonance chamber and the free ends of which carry partially transmitting mirrors for the passage of discrete active beams of coherent radiation. The two active beams are thereupon split into pairs of split beams and the split beams are focused upon the running web of wrapping material or upon the wrappers of successive rod-shaped articles to simultaneously form four rows of perforations.

Abstract: The tobacco stream which is formed at the underside of a foraminous conveyor and carries a surplus of tobacco particles is transported past a trimming device which removes the surplus to convert the stream into a filler which is thereupon wrapped into a web of cigarette paper. The mass flow of tobacco particles in the untrimmed stream is monitored by a detector which utilizes infrared light, and the signals from such detector are used to change the position of the conveyor relative to the trimming device so as to ensure that the mass flow of tobacco particles in the filler remains within a desired range. One or more additional detectors monitor the mass of flow tobacco particles in the filler upstream and/or downstream of the wrapping station, and the signals from such second detector or detectors are used to correct the position of the conveyor relative to the trimming device and/or to change the position of the trimming device relative to the conveyor.

Abstract: A shower of fibrous material is directed against the underside of the lower reach of a foraminous endless belt conveyor so that the fibrous material gathers into a continuous stream which is attracted to the conveyor by suction and is moved longitudinally past a trimming device which removes the surplus. The density of the stream is monitored upstream and downstream of the trimming device, and the corresponding signals are processed in an evaluating circuit into additional signals which are indicative of the quantity of the removed surplus. The removed surplus is weighed and the weighing device generates signals also denoting the quantity of the surplus. Such signals are compared with the additional signals and further signals, which denote the differences between the intensities of the compared signals, are used to modify signals denoting the density of the stream downstream of the trimming device. The thus modified signals are used to adjust the trimming device.

Abstract: The presence of protruding filaments in a woven endless belt for the transport of tobacco or filter material in a machine of the tobacco processing industry is detected by one or more optoelectronic detectors. Signals which are generated by such detectors are evaluated to transmit a defect signal only when the detectors generate signals which were in fact initiated by protruding filaments rather than by projecting particles of tobacco or filter material, and when the number of such signals per length of the belt reaches a preselected value which warrants the generation of a defect signal.

Abstract: Apparatus for optically scanning a moving cigarette rod for the presence of defects in its external surface has two annularly arranged groups of diodes which emit green light in the wavelength range of between 0.49 and 0.58.mu. and direct such light from the opposite sides of a plane that is normal to the moving rod so that the incident light is reflected by successive annular portions of the external surface of the rod into the aforementioned plane. The reflected light is focused by systems of lenses upon discrete photosensitive transducers through discrete slit diaphragms on the transducers themselves or on a thin metallic ring which is adjustably mounted on the support for the diodes and the systems of lenses.

Abstract: The exterior of successive filter cigarettes, filter rod sections or other rod-shaped articles of the tobacco processing industry is monitored for the presence of various defects including absence or improper orientation of filter mouthpieces, improperly applied or outwardly projecting uniting bands, absence of roundness and/or others by directing a beam of radiation along successive articles while they move sideways in the flutes of a drum-shaped conveyor. The beams of radiation are influenced by defects and are thereupon monitored for the purposes of generating signals which are indicative of defects, if any. The beam of radiation extends all the way along the full length of each article and can also extend partially or around the entire circumference of each article.

Abstract: A running web of cigarette paper or the like is perforated in a first portion of its path, thereupon tested for permeability by a pneumatic detector in a second portion of the path, and finally tested for permeability by an optical detector in a third portion of the path. Signals which are generated as a result of pneumatic testing are used to adjust the perforating unit in the first portion of the path. Signals which are generated as a result of testing by the optical detector are compared with a reference signal denoting the desired permeability of the web, and the web and perforating unit are arrested, or the cigarettes which contain defective portions of the web are segregated from satisfactory cigarettes, if the deviation of generated signals from the reference signal exceeds a threshold value.

Abstract: Apparatus for making perforations in continuous or interrupted webs of cigarette paper or the like has one or more perforating units serving to direct radiant or electrical energy against selected portions of the web to make holes therein. That portion of each perforating unit which surrounds the locus of propagation of energy beyond the respective perforating unit is externally cooled and cleaned by one or more streams of compressed gas which ensure that such portion cannot accumulate solid combustion products which could interfere with the propagation of energy toward the web. The stream or streams are furnished by the orifices of nozzles which can be provided in the carrier or carriers for the perforating units or can be outwardly adjacent to the carrier or carriers.

Abstract: Apparatus for making holes in a running web of tipping paper for filter cigarettes has a carrier for a battery of suitably distributed perforating units each of which has an optical system for focusing upon the running web a discrete beam of coherent radiation which is furnished by a laser. The making of holes entails the development of contaminants, and such contaminants are removed by air streams which are circulated through the perforating units not only to remove the contaminants but also to cool the optical systems of the respective perforating units. The web advances along the convex side of a shroud which maintains the web at an optimum distance from the optical systems of the perforating units. The shroud is installed between the web and the perforating units and has elongated slot-shaped apertures for the beams of radiation. The perforating units form several rows, and the shroud has or can have one elongated aperture for each row of perforating units.

Abstract: A running web of wrapping material which is about to be converted into adhesive-coated uniting bands for joining plain cigarettes with filter plugs in filter tipping machines is transported through the passage of a housing wherein the web travels through a series of spark gaps between pairs of spaced-apart electrodes. The sparks which are caused to jump across the gaps perforate the web with attendant development of ozone and particles of dust. The passage of the housing forms part of an endless path for the circulation of Argon which reduces the rate of development of ozone, which is cooled to cool the electrodes, and which is caused to pass through a filter serving to intercept the particles of dust which are removed from the spark gaps. The making of holes in a noble-gas atmosphere prolongs the useful life of the electrodes.

Abstract: A method of monitoring filters and sections in a filter tipping machine wherein pairs of coaxial plain cigarettes are united with filter plugs of double unit legnth by adhesive-coated bands. When a filter plug is missing, a mechanical or a photosensitive filter plug detector transmits a signal to a valve which admits compressed air to two nozzles to cause the plain cigarettes which are not separated by a filter plug to move toward each other so that a uniting band which is applied around the adjacent inner end portions of the thus shifted plain cigarettes can adequately connect the plain cigarettes to each other during further transport to a station where the united plain cigarettes can be readily segregated from satisfactory products.

Abstract: Apparatus for perforating a web of wrapping material or tubular wrappers of discrete filter cigarettes of unit length or double unit length in a filter tipping machine has a laser which is energizable at a frequency depending on the speed of the main prime mover of the machine to emit a beam which is reflected by a pivotable reflector to impinge alternately upon different portions of a single optical system or upon several discrete optical systems serving to focus the beam upon the web or upon discrete wrappers whereby the beam forms two or more rows or more complex patterns of perforations in the web or in the wrappers of successive cigarettes. The pivotable reflector can be omitted or is optional if a diffraction grating is placed in front of a single optical system so that the grating splits the beam into several discrete beams each of which is focused upon a different portion of the web or of the wrapper of a cigarette.

Abstract: A filter tipping machine wherein pairs of coaxial plain cigarettes are united with filter plugs of double unit length by adhesive-coated bands. When a filter plug is missing, a mechanical or a photosensitive filter plug detector transmits a signal to a valve which admits compressed air to two nozzles to cause the plain cigarettes which are not separated by a filter plug to move toward each other so that a uniting band which is applied around the adjacent inner end portions of the thus shifted plain cigarettes can adequately connect the plain cigarettes to each other during further transport to a station where the united plain cigarettes can be readily segregated from satisfactory products.