GB2514315A

GB2514315A - Cigarette filter monitoring apparatus

Info

Publication number: GB2514315A
Application number: GB201302024A
Authority: GB
Inventors: Dimitar Yanchev
Original assignee: Aiger Group AG
Current assignee: Aiger Group AG
Priority date: 2013-02-05
Filing date: 2013-02-05
Publication date: 2014-11-26
Also published as: GB201302024D0

Abstract

Cigarette filter monitoring apparatus (12) for monitoring cigarette filter sections is described. The apparatus comprises cigarette material conveyor apparatus (14, 16) for conveying cigarette material along a conveyor path. It also comprises a microwave sensor (26) located adjacent to the conveyor path to monitor such filter sections. The cigarette conveyor apparatus (14, 16) is constructed to convey elongate cigarettes with filter sections oriented transversely of the said conveyor path. A second microwave sensor (28) is located adjacent to the said conveyor path also to monitor such filter sections. The monitoring apparatus (12) may further comprise a microprocessor (34) connected to receive signals from the said first-mentioned microwave sensor (26) and the said second microwave sensor (28) and to provide an indication of the condition of the filter sections. A method of monitoring cigarette filters using such cigarette filter monitoring apparatus (12) is also detailed.

Description

Cigarette filter monitoring apparatus [0001] The present invention reiates to cigarette filter monitoring apparatus for monitoring cigarette filter sections, comprising cigarette material conveyor apparatus for conveying cigarette material along a conveyor path, and a microwave sensor located adjacent to the said conveyor path to monitor such filter sections.

[0002] EP-A-2243385, the whole contents of which are hereby imported into the present specification by way of direct reference, discloses such monitoring apparatus, in which cigarette filter rod is passed in a longitudinal direction through an annular microwave sensor.

[0003] A disadvantage of such a previously proposed construction is that damage may occur to the cigarette filter while it is being conveyed from the location of the monitoring apparatus to a location in which a cigarette with such a filter is assembled, or subsequent to assembly of the cigarette before it is forwarded for packaging, and such damage will not be ascertained from such monitoring apparatus.

[0004] US-A-2012/0006338, the whole contents of which are also hereby imported into the present specification by way of direct reference, discloses monitoring apparatus for monitoring low ignition propensity papers using what is referred to in that specification as a mini planar sensor. A mini planar sensor is a microwave sensor which generates a microwave field beyond one of its ends, the field being generated by a generally planar portion, for example a disc or button, of electrically conductive material. This may be integral with and at one end of an electrically conductive elongate portion of the same electrically conductive material which extends longitudinally within a generally cylindrical casing of electrically insulating material, the planar portion itself being close to an end of the casing.

It is this end which is located adjacent to the conveyor path. The sensor is connected to both generate and measure the resonance of the region of sensitivity of the sensor as a function of frequency, to give a measure of the mass and/or moisture content of material for the time being within the sensitivity region of the sensor.

[0005] According to the present invention there is provided cigarette filter monitoring apparatus having the construction set out in the opening paragraph of nbc present specification, in which the cigarette conveyor apparatus is constructing to convey elongate cigarettes with filter sections oriented transversely of the said conveyor path, in which a second microwave sensor is located adjacent to the said conveyor path also to monitor such filter sections, in which the said second microwave sensor is spaced apart from the first-mentioned microwave sensor in a direction along the said conveyor path, and in which the said first-mentioned microwave sensor, the said second microwave sensor and the said conveyor apparatus are so constructed and arranged that the said first-mentioned microwave sensor and the said second microwave sensor are located on opposite sides of the cigarettes relative to one another as the cigarettes pass by them, the monitoring apparatus further comprising a microprocessor connected to receive signals from the said first-mentioned microwave sensor and the said second microwave sensor and to provide an indication of the condition of the filter sections.

[0006] An advantage of such a construction of monitoring apparatus is that it is less susceptible to error from any asymmetry of the filter section. For example, in the event that the filter section comprises a frangible capsule containing a flavouring liquid, which capsule is to be in tact at the point-of-sale of the cigarette of which the filter section forms a part, it is possible that a broken capsule may be so located in the filter that the signal it creates in conventional monitoring apparatus is not easily distinguished from the signal given by an undamaged filter section. Monitoring apparatus made in accordance with the present invention however is less susceptible co such an error.

[0007] The cigarette conveyor apparatus may comprise two drum-shaped components each with a multiplicity of flutes around their periphery for receiving cigarettes respectively, the drum-shaped components be arranged to rotate about respective generally parallel axes of rotation in opposite senses, and being adjacent to one another to enable the transfer of cigarettes from one of the components to the other, the said first-mentioned microwave sensor and the said seoond microwave sensor be located adjacent to the peripheries of the two drum-shaped components respectively.

[0008] The peripheries of the drum-shaped components may be provided with respective annular recesses in registration with the said microwave sensors respectively.

[0009] The microwave sensors may comprise mini planar microwave sensors.

[0010] The microwave sensors may be electrically connected to a microprocessor which compares respective output signals from the sensors and issues signals indicative of the conditions of the cigarette filter sections in accordance with comparisons between those output signals.

[0011] The apparatus may be provided with an ejector electrically connected to the microprocessor to eject a cigarette from the conveyor path in the event that a signal issued by the microprocessor is indicative of a defective filter section.

[0012] The present invention extends to a cigarette manufacturing machine incorporating cigaretne filter monitoring apparatus in accordance with the present invention.

[0013] The present invention also extends to a method of monitoring cigarette filters using cigarette filter monitoring apparatus in accordance with the present invention. It also extends to a method of making cigarettes using a method and/or apparatus in accordance with the present invention.

[0014] An example of cigarette filter monitoring apparatus made in accordance with the present invention will now be described in greater detail with reference to the accompanying drawings in which: [0015] Figure 1 shows a diagrammatic elevational view of a cigarette making machine incorporating cigareute filter monitoring apparatus embodying the present invention, including electrical circuitry therefor; [0016] Figure 2 shows an axial sectional view of part of the apparatus shown in Figure 1;

[0017] Figure 2a shows electromagnetic field lines

generated by a part of the apparatus shown in Figure 1; and [0018] Figure 3 shows explanatory graphs.

[0019] The apparatus shown in Figure 1 comprises a cigarette manufacturing machine 10 below which is arranged cigarette filter monitoring apparatus 12.

[0020] The cigarette filter monitoring apparatus 12 comprises two drums 14 and 16 arranged one below the other, with the periphery of the upper drum 14 be arranged immediately below the cigarette manufacturing apparatus 10 so as to receive cigarettes 18 made thereby respectively in flutes 20 formed around the periphery of the drum 14. The flutes 20 extend across the periphery of the drum 14 so as to be generally parallel to an axis 22 of rotation thereof.

[0021] The lower drum 16 has the same construction as the upper drum 14 and is rotatable about its central axis 24 which extends generally parallel to the axis 22 of the upper drum 14.

[0022] Respective mini planar microwave sensors 26 and 28 are located adjacent to the peripheries of the drums 14 and 16 respectively, the sensor 26 having its sensitive end directed towards the right-hand side of the drum 14 as viewed in Figure 1, generally at the same level as the axis of rotation 22 and sufficiently close to the periphery of the drum 14 to ensure that the filter sections of the cigarettes 18 thereof pass within the region of sensitivity of the sensor 26.

[0023] The other sensor 28 is located adjacent to the periphery of the drum 16 in a corresponding fashion but adjacent to the left-hand side of the drum 16 as viewed in Figure 1 and generally at the same level as the axis of rotation 24 of the drum 16.

[0024] A linear conveyor 30 is arranged underneath the drum 16 so that the cigarettes are transferable from the drum 16 to the conveyor 30. The latter is provided with an ejector 32 located to enable it to eject cigarettes 18 from the conveyor 30.

[0025] The apparatus 10, the sensors 26 and 28 and the ejector 32 are all electrically connected to a microprocessor 34.

[0026] Further details of each drum 14 and 16 are shown in Figure 2, from which it is evident that each drum 14 or 16 is hollow and is formed with a plurality of suction vents 36 by virtue of which a lower pressure cf air maintained within the drum 14 or 16 is communicated to each cigarette 18 in a flute 20 to retain the cigarette 18 within that flute 20.

The sensor 26 or 28 is located to one side of the periphery of the drum 14 or 16 so as to be directed towards the middle of filter sections 38 of the cigarettes 18. The sensor 26 or 28 is elongate and is held to be generally at right angles to the periphery of the drum 14 or 16 for the time being adjacent to it. It is sufficiently close to the cigarette filter 38 to ensure that the filter section 38 passes through its region of sensitivity.

[0027] The periphery of the drum 14 or 16 is provided with an annular recess 40 to one side of its periphery, underneath a central position of the filter section 38 of each cigarette 18.

[0028] Each cigarette 18 has a filter section 38 which comprises two portions of filter material 42 spaced apart to create a cavity 44 between them within which has been inserted a capsule 46 of frangible material, the capsule 46 containing the menthol fluid which is released when the capsule 46 is broken.

[0029] Figure 2a shows lines 48 of an elecrromagnetic field 50 extending from the sensitive end 52 of the sensor 26 or 28. From this it is evident that the degree of sensitivity of the sensor 26 or 28 varies in dependence upon the distance between the end 52 and the material which is passing through its region of sensitivity, and that beyond a relatively small distance from the end 52, the sensitivity drops off rapidly.

[0030] With the apparatus is in use, the drum 14 is coupled to a motor (not shown) so as to be driven in a clockwise sense about its axis of rotation 22 as viewed in Figure 1, and the drum 16 is coupled to the motor to be driven in a counter-clockwise sense about its axis of rotation 24. The linear conveyor 30 is coupled to the motor to be driven in a direction from left to right as viewed in Figure 1.

[0031] Cigarettes 18 are transferred from the cigarette manufacturing apparatus 10 to the drum 14 so as to pass the sensor 26. when the cigarettes 18 reach the drum 16, the vents 36 of the drum 14 immediately underneath that cigarette are closed, whereas the corresponding vents 36 of the drum 16 are open so that the low pressure within the drum 16 is effective in transferring the cigarette from the conveyor drum 14 to the drum 16.

[0032] It will be appreciated that because of this manner of transfer of the cigarettes from drum 14 to drum 16, the sensors 26 and 28 are located on opposite sides respectively of each cigarette when it passes these sensors.

[0033] The cigarettes therefore continue along the conveyor path around the periphery of the drum 16 in a counter-clockwise direction as viewed in Figure 1 past the sensor 28.

[0034] The cigarettes 18 are then transferred to the linear conveyor 30 past the ejector 32. In the event that the signals received by the microprocessor 34 from the sensors 26 and 28 are indicative of a defective filter section, that cigarette is injected by the ejector 32 from the conveyor 30.

[0035] Faoh miorowave sensor 26 or 28 incorporates circuitry which provides a signal at its output indicative of the mass M of material for the time being within its sensitivity region 22, determined by the equation: M = * (1 ÷ k2F) * A in which k1 and k2 are constants ascertained from experimental tests on the apparatus (by noting the measure given by the sensor 26 or 28 for a given amount of material, and weighing the material to determine its mass) F = B/A, A is the change in the resonant frequency as compared to the resonant frequency of the sensor with absence of any material in its sensitivity region, and B is the increase in the half-value width of the resonance ourve oompared to that value with absence of any material in its sensitivity region.

Alternatively the electronic circuitry for performing this calculation may be provided in the microprocessor 34.

[0036] At the same time a measurement for this will depend upon how far away the mass being measured is from the sensitive end 52 of the sensor 26 or 28.

[0037] Figure 3 shows examples of the types of variation of measured mass that might occur for different filter sections as they pass by one or other of the sensors 26 and 28. The curve 54 peaks at a value ml which acccrding to preset values is recognised by the microprocessor 34 as being too low, correspondIng to the complete absence of any capsule 46 in the filter section 38. Such a measurement will cause the ejector 32 to remove the cigarette concerned from the linear conveyor 30 when cigarette reaches the ejector 32.

[0038] A curve such as that labelled 56 In Figure 3 peaks at a value m2 corresponding to an acceptable value.

[0039] However, a cigarette filter section which creates from one of the sensors 26 or 28 a curve 58 having a peak value m3, and from the other of the sensors 26 or 28 a curve having a peak m4 for which differs from the peak m3 by an amount greater than a threshold value retained within the microprocessor 34 will also cause the cigarette which gave rise to these signals to be rejected by the ejector 32. This Is because an asymmetry has been detected in the filter section 38 concerned, which would correspond for example to the capsule 46 being fractured. This In turn results in the liquid content of the capsule being released and causing the bulk of the capsule to be held on one side of the cavity 44 to create such a difference in the outputs from the sensors 26 and 28.

[0040] A further curve (not shown) which has a peak which exceeds a given threshold value, which would correspond to a cavity 44 containing two capsules, will also cause the cigarette concerned to be ejected by the ejector 32.

[0041] Numerous variations and modifications to the illustrated apparatus may occur to the reader without taking the resulting construction outside the scope of the present invention. Thus for example the calculations of the outputs from the sensors 26 and 28 may instead be set to measure the moisture content rather than the mass of what passes through the region of sensitivity of the sensor 26 or 28. The two drums 14 and 16 may be arranged alongside one another, on the same general horizontal level, rather than one below the other. Furthermore, the drums 14 and 16 may be of different respective diameters. The ejector 32 may be arranged adjacent to another drum (not shown) which defines part of the conveyor path, rather than being arranged adjacent to the linear conveyor 30. Indeed, the linear conveyor 30 may be replaced by another drum (not shown)

Claims

IClaims: 1. Cigarette filter monitoring apparatus for monitoring cigarette filter sections, comprising cigarette material conveyor apparatus for conveying cigarette material along a conveyor path, and a microwave sensor located adjacent to the said conveyor path to monitor such filter sections, in which the cigarette /conveyor apparatus is constructed to convey elongate cigarettes with filter sections oriented transversely of the said conveyor path, in which a second microwave sensor is located adjacent to the said conveyor path also to monitor such filter sections, in which the said second microwave sensor is spaced apart from the first-mentioned microwave sensor in a direction along the said conveyor path, and in which the said first-mentioned microwave sensor, the said second microwave sensor and the said conveyor apparatus are so constructed and arranged that the said first-mentioned microwave sensor and the said second microwave sensor are located on opposite sides of the cigarettes relative to one another as the cigarettes pass by them, the monitoring apparatus further comprising a * . microprocessor connected to receive signals from the said * . * * . * first-mentioned microwave sensor and the said second ***.** * microwave sensor and to provide an indication of the condition of the filter sections.
2. Cigarette filter monitoring apparatus according to claim 1, in which the cigarette conveyor apparatus comprises two drum-shaped components each with a multiplicity of flutes around their periphery for receiving cigarettes respectively, the drum-shaped components being arranged to rotate about respective generally parallel axes of rotation in opposite senses, and being adjacent to one another to enable the transfer of cigarettes from one of the components to the other, the said first-mentioned microwave sensor and the said second microwave sensor being located adjacent to the peripheries of the two drum-shaped components respectively.
3. Cigarette filter monitoring apparatus according to claim 2, in which the peripheries of the drum-shaped components are provided with respective annular recesses in registration with the said microwave sensors respectively.
4. Cigarette filter monitoring apparatus according to any preceding claim, in which the microwave sensors comprise mini planar microwave sensors.
5. Cigarette filter monitoring apparatus according to any preceding claim, in which the microwave sensors are electrically connected to a microprocessor which compares * * respective output signals from the sensors and issues I.....* signals indicative of the ccnditions of the cigarette filter sections in accordance with comparisons between those output *.** * signals.
6. Cigarette filter monitoring apparatus according to any preceding claim, in which the apparatus is provided with an ejector electrically connected to the microprocessor to eject a cigarette from the conveyor path in the event that a signal issued by the microprocessor is indicative of a defective filter section.
7. Cigarette filter monitoring apparatus substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.
8. A cigarette manufacturing machine incorporating cigarette filter monitoring apparatus as claimed in any preceding claim.
9. A method of monitoring cigarette filters using cigarette filter monitoring apparatus as claimed in any one of claims 1 to 7.
10. A method of making cigarettes using a method and/or apparatus as claimed in any preceding claim.U * * . * *e*** * . ** * * * * * **S*SflSe * * ** * SI *ISS