US3336478A - Apparatus for measuring the quality of a cigarette manufacturing process - Google Patents

Apparatus for measuring the quality of a cigarette manufacturing process Download PDF

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Publication number
US3336478A
US3336478A US390795A US39079564A US3336478A US 3336478 A US3336478 A US 3336478A US 390795 A US390795 A US 390795A US 39079564 A US39079564 A US 39079564A US 3336478 A US3336478 A US 3336478A
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US
United States
Prior art keywords
signal
density
rod
deviation
cigarette
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US390795A
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English (en)
Inventor
John W Franklin
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Brown and Williamson Holdings Inc
Original Assignee
American Tobacco Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by American Tobacco Co filed Critical American Tobacco Co
Priority to US390795A priority Critical patent/US3336478A/en
Priority to GB25653/65A priority patent/GB1044868A/en
Priority to SE8086/65A priority patent/SE314323B/xx
Priority to ES0314388A priority patent/ES314388A1/es
Priority to BE666295D priority patent/BE666295A/xx
Priority to NO158813A priority patent/NO122471B/no
Priority to LU48997D priority patent/LU48997A1/xx
Priority to DK367365AA priority patent/DK117887B/da
Priority to CH1065965A priority patent/CH431355A/fr
Priority to DE1532104A priority patent/DE1532104C3/de
Priority to NL6510953A priority patent/NL6510953A/xx
Application granted granted Critical
Publication of US3336478A publication Critical patent/US3336478A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Classifications

    • GPHYSICS
    • G08SIGNALLING
    • G08BSIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
    • G08B21/00Alarms responsive to a single specified undesired or abnormal condition and not otherwise provided for
    • G08B21/18Status alarms
    • G08B21/187Machine fault alarms
    • AHUMAN NECESSITIES
    • A24TOBACCO; CIGARS; CIGARETTES; SIMULATED SMOKING DEVICES; SMOKERS' REQUISITES
    • A24CMACHINES FOR MAKING CIGARS OR CIGARETTES
    • A24C5/00Making cigarettes; Making tipping materials for, or attaching filters or mouthpieces to, cigars or cigarettes
    • A24C5/32Separating, ordering, counting or examining cigarettes; Regulating the feeding of tobacco according to rod or cigarette condition
    • A24C5/34Examining cigarettes or the rod, e.g. for regulating the feeding of tobacco; Removing defective cigarettes
    • A24C5/3412Examining cigarettes or the rod, e.g. for regulating the feeding of tobacco; Removing defective cigarettes by means of light, radiation or electrostatic fields
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N23/00Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00
    • G01N23/02Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by transmitting the radiation through the material
    • G01N23/06Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by transmitting the radiation through the material and measuring the absorption
    • G01N23/12Investigating or analysing materials by the use of wave or particle radiation, e.g. X-rays or neutrons, not covered by groups G01N3/00 – G01N17/00, G01N21/00 or G01N22/00 by transmitting the radiation through the material and measuring the absorption the material being a flowing fluid or a flowing granular solid
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N33/00Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
    • G01N33/02Food
    • GPHYSICS
    • G06COMPUTING; CALCULATING OR COUNTING
    • G06GANALOGUE COMPUTERS
    • G06G7/00Devices in which the computing operation is performed by varying electric or magnetic quantities
    • G06G7/12Arrangements for performing computing operations, e.g. operational amplifiers
    • G06G7/20Arrangements for performing computing operations, e.g. operational amplifiers for evaluating powers, roots, polynomes, mean square values, standard deviation
    • GPHYSICS
    • G07CHECKING-DEVICES
    • G07CTIME OR ATTENDANCE REGISTERS; REGISTERING OR INDICATING THE WORKING OF MACHINES; GENERATING RANDOM NUMBERS; VOTING OR LOTTERY APPARATUS; ARRANGEMENTS, SYSTEMS OR APPARATUS FOR CHECKING NOT PROVIDED FOR ELSEWHERE
    • G07C3/00Registering or indicating the condition or the working of machines or other apparatus, other than vehicles
    • G07C3/14Quality control systems

Definitions

  • ABSTRACT OF THE DISCLOSURE The density of a rod of tobacco is measured continu ously by a radiation gauge and electronically compared with a standard density signal. The resulting density deviation signal is passed through a non-linear voltage divider and integrated over time to produce an integrand signal varying as a function of the magnitude of the deviation signal raised to a power greater than unity. The integrated signal representative of the quality of the tobacco rod manufacturing process is periodically sampled and presented to indicators and alarm devices.
  • This invention relates to the manufacture of cigarettes and, more particularly, to apparatus for automatically measuring and indicating the quality of cigarettes manufactured by cigarette making machines.
  • One cigarette characteristic which provides a reliable indication of final overall quality is that of the distribution of weight among the cigarettes produced.
  • the final cigarette weight varies as a function of tobacco moisture content, tobacco density, firmness of packing, etc.
  • Automatic radiation type gauge systems have been proposed for continuously monitoring the production of cigarette rod material and for regulating automatic machinery which controls the amount of tobacco supplied to the rolling apparatus and the like. Although such automatic monitoring and regulating systems are intended to function automatically without human intervention, it has frequently been found that the distribution of cigarette weights does not fall Within the narrow tolerances imposed by the high quality standards of commercial production.
  • the present invention is therefore an apparatus for measuring the quality of a cigarette manufacturing process wherein a rod of tobacco moves past a sensing station.
  • the apparatus comprises radiation gauge means for producing a deviation signal corresponding to the deviation of the density of the rod at the station from a standard value of density, circuit means for operating upon the deviation signal in a non-linear manner to produce an in-' teoffice signal varying as a function of the deviation signal raised to a power greater than unity, means for inte' grating the integrand signal over a period of time, and means for indicating the result of the integration.
  • the figure is a block and schematic diagram illustrating the electrical circuits provided by the present invention.
  • a varying D-C measured density signal from a radiation type gauge is utilized as an input monitoring signal to the automatic alarm of the present invention.
  • the D-C measured density signal from the gauge is inversely proportional to the density of the cigarette rod moving past the gauge. It is customary practice to diiferentially compare the signal voltage produced by radiation particles passing through the moving cigarette rod with a reference standard density signal produced by radiation transmitted through a standard rod material. The result of this comparison is a deviation signal 10, shown in the figure, from the measuring head corresponding to the variation of the density of the cigarette rod at the sensing station from the standard value of cigarette density.
  • the deviation signal 10 is zero for exactly standard Weight cigarette rod and increases in a negative or positive direction from the reference zero value for cigarette rod material that is respectively overweight or underweight.
  • the above described varying signal 10 is submitted to a 60 cycle rejection filter 11 and and amplified by a chopper-type amplifier 12, and the chopped A-C voltage is rectified by a bridge rectifier 13 to produce across a filter capacitor 14 a magnitude signal which is proportional to the absolute magnitude of the deviation of the cigarette rod density at the sensing station from the standard density.
  • This magnitude signal across capacitor 14 is then applied to a non-linear voltage divider comprising an output shunt arm 15 and a non-linear network series arm including zener diodes 16, 17, 18 and shunt resistance arms 19, 20, 21,.
  • the zener diodes 16, 17, 18 are provided to switch in the shunt resistance arms 20, 21, and 22 in parallel with the resistor 19 as the input voltage progressively increases in the positive direction.
  • the resistance value of the series arm of the voltage divider thus varies inversely in a non-linear manner with the applied input voltage from the rectifier 13 so that as the magnitude signal across the filter capacitor 14 increases, the resistance value of the series arm in the divider decreases and a larger proportion of the input voltage is applied across the output arm 15 of the divider to produce an integrand signal which is then transmitted to an integrating circuit 23, 24.
  • the integrand signal presented to the integrator circuit cor-responds to the deviation of the cigarette rod density raised to a power greater than unity.
  • the non-linear divider characteristic is adapted to great- I 1y expand the deviation signal as the cigarette rod density departs from the value corresponding to standard Weight cigarettes. In this manner small variations from the standard density value will be accorded relatively less weight in the integration process than larger variations from the standard Value.
  • This non-linear operation serves to make the apparatus less sensitive to small variations from the standard density which are to be expected in any process and much more sensitive to large variations in density even though these latter variations may be of short duration.
  • the resistance of the series arm of the divider in a prefer-red embodiment of the invention varies inversely with the square of the applied magnitude signal so that the result of the integration over a period of time corresponds to the statistical variance (c2) of the distribution of density of the rod passing the sensing station during a comparison of one cigarette process or machine with another.
  • Variance may be understood as a measure of the sharpness of a process distribution curve; thus a process in which the cigarette weights are distributed over a wide range of values will have a larger variance than a process in which the cigarette weights are limited to a narrow range of values around a standard or mean value. In this way it can be seen that variance is a direct measure of the quality of a process, i.e., how closely its product adheres to a desired standard value.
  • the equation for variance takes the form where n is the number of samples, dn is the nth sample of density and d* is the standard value of density.
  • d is the number of samples
  • d* is the standard value of density.
  • T is the period of time over which the integration is made. The preferred embodiment uses this latter process to obtain the variance.
  • the output voltage from the non-linear divider developed across resistance 15 is integrated by a resistor 23 and capacitor 24 network.
  • a diode 25 is connected in series with the network resistor 23 and is poled to conduct and charge the capacitor 24 when a positive voltage is applied to the integrating resistor 23. The diode 25 accordingly prevents discharge of the capacitor 24 through the resistance 23.
  • the volt-age stored on the integrator capacitor 24 may be measured after a suitable integration period by conventional voltmeter means to give a measure of the variance of the process.
  • the result of the integration stored in the integrating capacitor 24 is periodically read out by closure of the normally opened contacts 26 of a relay switch located in a timer controller 27, a step voltage from the capacitor 24 being applied across the input terminals of a pulse amplifier 28.
  • the output pulse voltage from the amplifier 28 is applied to separate trigger switches 29 and 30, each of which has an adjustable operating threshold control 31 and 32.
  • the trigger switches 29 and 30 advantageously comprise thyratron controlled relay switches which are normally biased to the off condition by the variable threshold controls 31 and 32.
  • the trigger switch 29 is negatively biased so that pulse voltages from the amplifier 28 corresponding to standard values of cigarette weight distribution does not fire the thyratron into the conducting state.
  • the output pulse from the amplifier 28 exceeds the cut-off bias value provided by the threshold adjust 31 and the trigger switch 29 is fired, opening the normally closed trigger switch contacts 33 associated with trigger switch 29 and simultaneously closing the normally open trigger switch contacts 34.
  • the green indicator lamp 35 which normally indicates production of normal weight cigarettes is turned off and the white indicator lamp 36, indicating production of slightly off-weight cigarettes, is turned on.
  • the trigger switch 30 is turned on so as to open the normally closed contacts 37 and to close the normally open contacts 38.
  • the white light 34 is turned off and the red indicator light 39 is turned on, thus warning the operator that the production weight distribution has departed by a significant amount from the normal desired value.
  • the relay contacts 26 are opened by the timer controller 27 and its normally open switch contacts 40 are momentarily closed. Closure of the cont-acts 40 completely discharges the capacitor 24, thereby conditioning the capacitor to accept a new signal voltage from resistance 15.
  • the contacts 40 are opened by the timer controller 27 and the capacitor 24 is allowed to charge for a period of time sufficient to assure build-up of the peak voltage appearing across the shunt resistance 15. For the component values given above, a charge time of approximately 55 seconds has been found to be satisfactory.
  • the trigger switches 29 and 30 are re-set to an oil condition just prior to the completion of the charge period by the closure of the switch contacts 41 by the timer controller 27.
  • the switch contacts 41 are advantageously connected to ground the anodes and thereby re-set the thyratrons to a biased off condition.
  • the read-out switch contacts 26 are again closed and the signal pulse developed at the output of the amplifier 28 is again evaluated by the trigger switches 29 and 30.
  • controllers circuits can be utilized to perform the time sequence control of the read-out switch 26, the discharge switch contacts 40 and the re-set switch contacts 41.
  • the controller 27 can, for example, comprise a motor driven time-sequence control switch.
  • Apparatus for measuring the quality of a cigarette manufacturing process wherein a rod of tobacco moves past a sensing station comprising:
  • circuit means for operating upon the deviation signal in a non-linear manner to produce an integrand signal varying as a function of the magnitude of the deviation signal raised to a power greater than unity;
  • (0) means for integrating the integrand signal over a period of time
  • Apparatus according to claim 1 having means for comparing the result of the integration with a threshold value and actuating an alarm when the result exceeds the threshold value.
  • Apparatus for measuring the-quality of a cigarette manufacturing process wherein a rod of tobacco moves past a sensing station comprising:
  • circuit means for operating .upon the magnitude signal in a non-linear manner to produce an integrand signal varying as a function of the magnitude signal raised to a power greater than unity;
  • Apparatus for measuring the quality of a cigarette manufacturing process wherein a rod of tobacco moves past a sensing station comprising:
  • the apparatus of claim 4 having means for comparing the result of the integration with a threshold value and actuating an alarm when the result exceeds the threshold value.
  • Apparatus for measuring the quality of a cigarette manufacturing process wherein a rod of tobacco moves past a sensing station comprising:
  • (0) means for comparing the measured density signal with the standard density signal to produce a deviation signal proportional to the deviation of the density of the rod at the sensing station from the standard value of density;
  • (g) means for comparing the result of the integration with a threshold value and actuating an alarm when the result exceeds the threshold value.

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  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • General Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • General Health & Medical Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Biochemistry (AREA)
  • Theoretical Computer Science (AREA)
  • Analytical Chemistry (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Food Science & Technology (AREA)
  • Mathematical Physics (AREA)
  • Business, Economics & Management (AREA)
  • Computer Hardware Design (AREA)
  • Software Systems (AREA)
  • Toxicology (AREA)
  • Automation & Control Theory (AREA)
  • Quality & Reliability (AREA)
  • Emergency Management (AREA)
  • Medicinal Chemistry (AREA)
  • Manufacturing Of Cigar And Cigarette Tobacco (AREA)
US390795A 1964-08-20 1964-08-20 Apparatus for measuring the quality of a cigarette manufacturing process Expired - Lifetime US3336478A (en)

Priority Applications (11)

Application Number Priority Date Filing Date Title
US390795A US3336478A (en) 1964-08-20 1964-08-20 Apparatus for measuring the quality of a cigarette manufacturing process
GB25653/65A GB1044868A (en) 1964-08-20 1965-06-17 Improvements in continuous quality indicator for cigarette maker
SE8086/65A SE314323B (fr) 1964-08-20 1965-06-18
ES0314388A ES314388A1 (es) 1964-08-20 1965-06-19 Un aparato para medir la calidad de un procedimiento de fabricacion de cigarrillos.
BE666295D BE666295A (fr) 1964-08-20 1965-07-02
LU48997D LU48997A1 (fr) 1964-08-20 1965-07-06
NO158813A NO122471B (fr) 1964-08-20 1965-07-06
DK367365AA DK117887B (da) 1964-08-20 1965-07-16 Apparat til indikering af kvaliteten af en cigaretfremstillingsporces.
CH1065965A CH431355A (fr) 1964-08-20 1965-07-29 Appareil pour surveiller la variation de la densité du tabac dans une machine à fabriquer des cigarettes
DE1532104A DE1532104C3 (de) 1964-08-20 1965-08-17 Vorrichtung zur Überwachung der Qualität eines Tabakstranges
NL6510953A NL6510953A (fr) 1964-08-20 1965-08-20

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US390795A US3336478A (en) 1964-08-20 1964-08-20 Apparatus for measuring the quality of a cigarette manufacturing process

Publications (1)

Publication Number Publication Date
US3336478A true US3336478A (en) 1967-08-15

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US390795A Expired - Lifetime US3336478A (en) 1964-08-20 1964-08-20 Apparatus for measuring the quality of a cigarette manufacturing process

Country Status (11)

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US (1) US3336478A (fr)
BE (1) BE666295A (fr)
CH (1) CH431355A (fr)
DE (1) DE1532104C3 (fr)
DK (1) DK117887B (fr)
ES (1) ES314388A1 (fr)
GB (1) GB1044868A (fr)
LU (1) LU48997A1 (fr)
NL (1) NL6510953A (fr)
NO (1) NO122471B (fr)
SE (1) SE314323B (fr)

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2033920A1 (de) * 1969-07-09 1971-01-14 AMF Ine . New York, NY (V St A ) Verfahren und Einrichtung zum elektropneumatischen Prüfen von Ziga retten
US3581558A (en) * 1967-12-18 1971-06-01 Goodrich Co B F Test instrument for determining the shear modulus of elastomeric materials
US3726132A (en) * 1969-04-28 1973-04-10 Monsanto Co Apparatus for indicating departure from predetermined limits
US4280187A (en) * 1978-09-29 1981-07-21 Hauni-Werke Korber & Co. Kg Method and apparatus for pinpointing the causes of malfunction of machines for the manufacture and/or processing of cigarettes or the like
CN105105326A (zh) * 2015-07-28 2015-12-02 郑州长河电子工程有限公司 基于ipc卷烟机烟支重量控制及质量检测一体化装置及方法
CN115902096A (zh) * 2021-08-27 2023-04-04 贵州中烟工业有限责任公司 一种烟用丝束质量检测方法及系统

Families Citing this family (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4625737A (en) * 1982-12-30 1986-12-02 Philip Morris Incorporated Foamed, extruded, tobacco-containing smoking article and method of making the same
US4632131A (en) * 1984-07-03 1986-12-30 Philip Morris Incorporated Foamed, extruded, coherent multistrand smoking articles
DE3738983C2 (de) * 1986-11-28 2002-02-14 Hauni Werke Koerber & Co Kg Verfahren und Vorrichtung zur Herstellung eines Faserstrangs der tabakverarbeitenden Industrie
US10928502B2 (en) * 2018-05-30 2021-02-23 Richwave Technology Corp. Methods and apparatus for detecting presence of an object in an environment

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3074641A (en) * 1957-11-29 1963-01-22 Thompson Ramo Wooldridge Inc Electronic stepping integrator circuit
US3096434A (en) * 1961-11-28 1963-07-02 Daniel Orifice Fitting Company Multiple integration flow computer
US3242327A (en) * 1961-10-27 1966-03-22 Phillips Petroleum Co Analysis and ratio computing apparatus
US3259746A (en) * 1960-02-29 1966-07-05 American Tobacco Co Apparatus for automatically weighing and totalizing the production time intervals of a plurality of different weight categories of cigarettes during manufacture
US8664556B2 (en) * 2009-11-03 2014-03-04 Mitsubishi Electric Corporation Switch device operating mechanism

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3074641A (en) * 1957-11-29 1963-01-22 Thompson Ramo Wooldridge Inc Electronic stepping integrator circuit
US3259746A (en) * 1960-02-29 1966-07-05 American Tobacco Co Apparatus for automatically weighing and totalizing the production time intervals of a plurality of different weight categories of cigarettes during manufacture
US3242327A (en) * 1961-10-27 1966-03-22 Phillips Petroleum Co Analysis and ratio computing apparatus
US3096434A (en) * 1961-11-28 1963-07-02 Daniel Orifice Fitting Company Multiple integration flow computer
US8664556B2 (en) * 2009-11-03 2014-03-04 Mitsubishi Electric Corporation Switch device operating mechanism

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3581558A (en) * 1967-12-18 1971-06-01 Goodrich Co B F Test instrument for determining the shear modulus of elastomeric materials
US3726132A (en) * 1969-04-28 1973-04-10 Monsanto Co Apparatus for indicating departure from predetermined limits
DE2033920A1 (de) * 1969-07-09 1971-01-14 AMF Ine . New York, NY (V St A ) Verfahren und Einrichtung zum elektropneumatischen Prüfen von Ziga retten
US4280187A (en) * 1978-09-29 1981-07-21 Hauni-Werke Korber & Co. Kg Method and apparatus for pinpointing the causes of malfunction of machines for the manufacture and/or processing of cigarettes or the like
CN105105326A (zh) * 2015-07-28 2015-12-02 郑州长河电子工程有限公司 基于ipc卷烟机烟支重量控制及质量检测一体化装置及方法
CN115902096A (zh) * 2021-08-27 2023-04-04 贵州中烟工业有限责任公司 一种烟用丝束质量检测方法及系统

Also Published As

Publication number Publication date
BE666295A (fr) 1965-11-03
GB1044868A (en) 1966-10-05
NO122471B (fr) 1971-06-28
ES314388A1 (es) 1966-04-16
DE1532104B2 (de) 1974-11-07
SE314323B (fr) 1969-09-01
CH431355A (fr) 1967-02-28
DK117887B (da) 1970-06-08
DE1532104A1 (de) 1969-07-24
LU48997A1 (fr) 1967-01-06
NL6510953A (fr) 1966-02-21
DE1532104C3 (de) 1975-07-03

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