US2938521A - Tobacco-manipulating machines - Google Patents

Description

May 31, 1960 R. LANORE TOBACCO-MNIPULATING MACHINES Filed Dec. 10, 1957 4 Sheets-Sheet 1 INVENTOR rm ATTORNE Y3 May 31, 1960 a. muons 2,938,521

ToBAcco-mmmnm MACHINES Filed Doc. 10, 1957 Stats-Shut 2 INVENTOR 4#*"' May 31, 1960 R. LANORE 'romccmmmmmc mcmuss 4 Sheets-Sheet 3 Filed Dec. 10, 1957 INVENTOR ATTORNE Y5 May 31, 1960 Filed Dec.

TOBACCO-MANIFULATING MACHINES 4 Sheets-Sheet 4 Fig .4.

L fifivvm SL L 138 l raw-5W /N VE N TOR A TTORNE X? TOBACCO-MANIPULATING MACHINES Raymond lLanore, Paris, France, assignor to Uslnes Decoull 8A., Paris, France, a French company Filed Dec. 10, 1957, Ser. No. 701,898

Claims priority, application France Jan. 11, 1957 Claims. (Cl. 131-21) This invention concerns improvements in or relating to tobacco-manipulating machines (for example continuous rod cigarette-making machines) in which a continuous tobacco filler is formed, which filler (for example after being enclosed in a paper wrapper) is to be cut at intervals to form individual tobacco articles such as cigarettes.

One difficulty that arises in the formation of a continuous tobacco filler is the tendency of the filler to contain varying quantities of tobacco along its length. It has been proposed, for example in United States Patent No. 2,660,178, dated November 24, 1953, or in the specification and drawings of United States application, Serial No. 702,104, filed December 11, 1957, to form a filler by first forming a tobacco stream whose cross-sectional size is greater than desired, and then removing excess tobacco, by means of a trimming device, so as to trim the stream to a predetermined cross-sectional size. If the density of the tobacco along the length of the stream is uniform, then the filler formed by removing surplus tobacco will be of uniform weight along its length. If however, the density of the stream varies along its length, the filler, although trimmed to uniform cross-sectional size, will vary in weight. It is usually desired that the tobacco articles produced from the filler (e.g. cigarettes) should as far as practicable be of uniform weight, and for this purpose the weight per unit length of the tiller should as far as practicable be uniform.

It has previously been proposed to employ various devices to measure the mass per unit length of a tobacco stream or filler in a continuous rod cigarette-making machine, or to defect deviations from a standard, and it has also been proposed to utilize the results of such measuring or detecting operations to alter the rate of feed of tobacco to form the stream. One example of such known measuring devices is a device employing a source of penetrative radiation, such as beta radiation, and means to measure the quantity of such radiation absorbed by the tobacco stream or filler.

According to the present invention there is provided, in a tobacco-manipulating machine such as a continuous rod cigarette-making machine, means to form and feed forwardly a tobacco stream whose cross-sectional size is greater than required, a trimming device to remove surplus tobacco from the stream, a measuring device arranged to measure the quantity of tobacco in a part of the stream close to the said trimming device, and adjusting means responsive to measuring operations by the said measuring device to cause relative movement, laterally of the stream, between the stream and the trimming device, so as to vary the cross-sectional size to which the stream is trimmed. The last-named means may comprise means to move laterally a conveyor by which the stream is conveyed, so that a part of the stream is moved towards and away from the trimming device.

It is to be understood that by the word "laterally," as used herein and in the appended claims, is meant in a direction transverse to the direction of lengthwise movement of the stream. For example the stream may pass nitc States Patent beneath the trimming device and may be supported by a conveyor tape which can be raised or lowered in order go move the stream towards or away from the trimming evtce.

Further according to the invention there is provided in a tobacco-manipulating machine such as a continuous rod cigarette-making machine, means to form and feed forwardly a tobacco stream whose cross-sectional size is greater than required, a channel through which the said stream is moved, a trimming device to remove surplus tobacco from the stream, a measuring device to measure the quantity of tobacco in a part of the stream close to the said trimming device, and means responsive to measuring operations by the said measuring device to vary the cross'sectional size of the said channel, so as to vary the cross-sectional size to which the stream is trimmed. For example, a part of the channel which supports a tobaccoconveying band may be moved towards and away from. me trimming device.

The said measuring device may be arranged to measure that part of the stream which has just passed the trimming device.

Apparatus in accordance with the invention will now be described by way of example with reference to the accompanying drawings, in which:

Figure 1 is a longitudinal section showing the feed end of a cigarette-making machine in which a tobacco stream is formed;

Figure 2 is a similar view showing on a larger scale the trimming device for separating and removing the excess tobacco, and its adjustment device;

Figure 3 is a sectional view of the same device, the section being taken upon the line 3-3 of Fig. 2; and

Figure 4 is a block and wiring diagram of the electric circuit for regulating the average density of the cigarettes.

Referring now to the arrangement shown more particularly in Figs. 1 to 3 of the drawings, the tobacco is spread by a distributor 1 on to an endless travelling band 2 between the walls 3 and 4 of a shoot-type hopper. A stream of tobacco is thus formed and fed forwardly on the band 2 from the rear wall 3 to the leading wall a of the hopper, the tobacco being supplied at a sufiicient rate to form a stream whose cross-sectional size is greater than required.

Between the points 5 and 6 of the band travel a trimming device is arranged to separate and remove any excess tobacco from the stream 8. In Fig. 1 this device is illustrated diagrammatically in the form of a pair of circular disc-like cutters 12. The band 2 travels through a channel which forms it, in the region of the trimming device, to U cross-section.

Beyond the trimming device, there is arranged between the points 6 and 7, Fig. l, a measuring device 25 for detecting any variations in the density of the tobacco stream which is to be subsequently utilized in the actual cigarettemakiug process.

Then the stream is delivered on to an endless paper web 9 guided by a small roller 10 and supported thereafter by an endless band 11 which carries along the paper web loaded with tobacco through the cigaretteforming members.

The device for removing the excess tobacco above the selected level comprises a pair of rotary circular cutters 12 overlapping each other by about .04" and rotating at a peripheral velocity exceeding by about 15% the linear speed of the band 2. The excess tobacco, which extends above the cutting plane, is trimmed off by the cutters and returned to the distributor by a suitable device (not shown).

The channel through which the band 2 moves under the cutters 12 is formed by bars 23, guides 24, and a vertically adjustable bed plate 13. The channel has,-in the assess:

region of the cutters 12, a constant width (which may be within the range of 95 to .4") and a variable height h, this height h, being adjusted by altering the vertical position of the bed plate 13. The height of this section (Fig. 3) can be varied from about W to 1%".

The vertical position of the bed plate 13 is adjusted automatically by a servomotor 14. This servo-motor comprises a reduction gear 15 driving a chain sprocket 16 mounted on a shaft 17 and adapted to drive another chain sprocket 18 mounted on the shaft 19. This shaft 19 is formed with a screw-threaded portion engaging an internally screw-threaded member 20 secured on a slidebar 21 arranged to slide on a fixed guiding support 22. This slide-bar 21 is integral with the bed plate 13.

The servo-motor 14 is adapted to rotate in either direction and its movements are controlled by the de tecting device. When the motor is stopped, the bed plate 13 remains in its position of adjustment; when the motor rotates in one direction, the bed plate 13 rises, and when the motor rotates in the other direction, the bed plate 13 descends.

The travelling band 2 follows the up and downward movements of the bed plate 13, the latter having a concave rounded upper face and the band having its lateral marginal portions extending to a greater or less extent into the gap left between the bars 23 and guide members 24.

A measuring or detecting device 25, which may be of any known and suitable type, is positioned just beyond the trimming zone, and supplies an electric current whose voltage and strength are determined by the mass per unit length of the trimmed stream of tobacco carried along by the travelling band 2.

This current may be utilized for controlling the servomotor 14 by resorting to known methods and devices comprising an amplifier 26, an integrator 27 and an indicator or measuring instrument 28. Finally, across the output terminals of the indicator 28 a voltage is available which is zero when the discrepancy between the average density of the stream and the desired average density is null, and positive or negative according as this average density is higher or lower than the desired average density.

It is desirable to provide an integrator adapted to supply the average data measured during about one second, so that the measuring instrument will indicate the difierences occuring over a length of the stream of the order of 60 inches, between the desired and actual average mass per unit length of the stream.

The proper direction of rotation of the motor 14 is obtained by means of two electromagnetic contactors 29, 30 having their armatures operatively connected to pivoting levers 31, 32, and 33, 34 respectively, these levers carrying movable contacts and being normally urged to their contact-breaking position by spring means.

Contactors 29, 30 are energized through the circuit fed with the current from the measuring instrument 28. This circuit comprises a biased relay 35 actuating a contact arm 36 to make contact with a contact 37 or a contact 38. This relay 35 is energized only when the voltage across its terminals is higher than a predetermined value, for no correction in the vertical position of the bed plate 13 is required unless the difi'erence between the real and the desired average mass per unit length exceeds a permissible value.

This circuit also comprises a switch 39 actuated by a cam 40. This cam is driven continuously from the main shaft of the machine (not shown). The cam 40 accomplishes one revolution in about two seconds, and the switch 39 is closed during one second.

During each cycle of the cam 40 the switch 39 closes the circuit of the measuring instrument; if the voltage across the terminals A and B is zero or lower than the minimum value necessary to energize the relay 35, no current flows through the windings of contactors 29 or 30, and the motor 14 is not energized. If the voltage across the terminals A and B is positive, (for example because the average mass per unit length of the cigarette rod has become higher than the desired average) and exceeds the minimum value required for energizing the relay 35, the latter will actuate the contact arm 36 to make contact with the fixed contact 37, the contactor 29 being thus energized to operate the tandem levers 31 and 32, and the motor 14 will rotate in the direction which causes the bed plate 13 to move upwards.

If the voltage across terminals A and B is negative, the relay 35 actuates the contact arm 36 to make contact with the fixed contact 38 and the other contactor 30 becomes energized, thereby causing the motor 14 to rotate in the direction which causes the bed plate 13 to move downwards.

As shown in Figures 1, 2 and 3, the stream originally formed on the conveyor band 2 is deeper than required, and as this stream approaches the trimming device, its uppermost part extends above the upper level of the guide members 24 and constitutes surplus tobacco which is removed by the trimming device, which thus trims the stream to the desired cross-sectional size. It will be seen that by vertically adjusting the position of the bed plate 13 by moving the latter towards and away from the trimming device in the manner described above, it is possible to cause relative movement, laterally of the stream, between the stream and the trimming device. Such vertical adjustments of the bed plate 13, which supports the band 2, have the effect of varying the cross-sectional size of the channel through which the stream moves past the trimming device, and therefore of varying the crosssectional size to which the stream is trimmed by the cutters 12. These vertical adjustments are, as explained above, made in response to measuring operations by the measuring device 25.

It will be seen that by means of the present invention it is possible to efiect very rapid adjustments to the crosssectional size to which the stream is trimmed in response to the data supplied by the measuring device,

' because the means for efiecting these adjustments, namely the trimming device, can be located very close to the measuring device. It will be seen that this arrangement enables corrections to be made very much more rapidly than in a case where, for example, corrections are effected by altering the rate of feed of tobacco from the hopper of the machine, since in the latter case, considerable time elapses between the moment when the alteration of the rate of feed is made, and the moment when a corresponding alteration results in the tobacco stream or filler in the region where the measurement takes plate. In other words, the present invention makes it possible to reduce the distance between the place where the measurement of the stream occurs, and the place where the adjustment of the cross-sectional size of the stream takes place, and consequently to reduce the time required for such adjustment to become etfective.

If desired, the measuring device may he so located as to measure the stream as the latter approaches the trimming device, instead of being located as shown in the accompanying drawings.

What I claim as my invention and desire to secure by Letters Patent is:

1. In a tobacco-manipulating machine such as a continuous rod cigarette-making machine, means to form and feed forwardly a tobacco stream whose cross-sectional size is greater than required, a trimming device to remove surplus tobacco from the stream, a measuring device arranged to measure the quantity of tobacco in a part of the stream passing said measuring device, and ad usting means responsive to measuring operations by the said measuring device to cause relative movement, laterally of the stream, between the stream and the trimming device, so as to vary the cross-sectional size to w an is trimmed.

2. Apparatus as claimed in claim 1 comprising a conveyor by which the stream is conveyed, and wherein the said adjusting means comprises means to move laterally the said conveyor, so that a part of the stream is moved towards and away from the trimming device.

3. In a tobacccrmanipulating machine such as a continuous rod cigarette-making machine, means to form and feed forwardly a tobacco stream whose cross-sectional size is greater than required, a channel through which the said stream is moved, a trimming device to 10 remove surplus tobacco from the stream, a measuring device to measure the quantity of tobacco in a part of the stream passing said measuring device, and means responsive to measuring operations by the said measuring device to vary the cross-sectional size of the said channel, so as to vary the cross-sectional size to which the stream is trimmed.

4. Apparatus as claimed in claim 3, wherein a part of the channel which supports a tobacco-conveying band is movable towards and away from the trimming device.

5. Apparatus as claimed in claim 1, wherein the said measuring device is arranged to measure that part of the stream which has just passed the trimming device.

References Cited in the file of this patent UNITED STATES PATENTS 2,264,725 Shoupp et a1. Dec. 2, 1941

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