US3360721A - Determination of moisture in tobacco - Google Patents

Determination of moisture in tobacco Download PDF

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Publication number
US3360721A
US3360721A US320015A US32001563A US3360721A US 3360721 A US3360721 A US 3360721A US 320015 A US320015 A US 320015A US 32001563 A US32001563 A US 32001563A US 3360721 A US3360721 A US 3360721A
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United States
Prior art keywords
holder
sample
tobacco
cylinder
attenuation
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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
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US320015A
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English (en)
Inventor
James O Pullman
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.)
Liggett Group LLC
Original Assignee
Liggett and Myers 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 Liggett and Myers Tobacco Co filed Critical Liggett and Myers Tobacco Co
Priority to US320015A priority Critical patent/US3360721A/en
Priority to DE19641498863 priority patent/DE1498863A1/de
Priority to GB44251/64A priority patent/GB1028720A/en
Priority to CH1404864A priority patent/CH426591A/fr
Priority to BE655112D priority patent/BE655112A/xx
Application granted granted Critical
Publication of US3360721A publication Critical patent/US3360721A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N22/00—Investigating or analysing materials by the use of microwaves or radio waves, i.e. electromagnetic waves with a wavelength of one millimetre or more
    • G01N22/04—Investigating moisture content
    • A—HUMAN NECESSITIES
    • A24—TOBACCO; CIGARS; CIGARETTES; SIMULATED SMOKING DEVICES; SMOKERS' REQUISITES
    • A24B—MANUFACTURE OR PREPARATION OF TOBACCO FOR SMOKING OR CHEWING; TOBACCO; SNUFF
    • A24B9/00—Control of the moisture content of tobacco products, e.g. cigars, cigarettes, pipe tobacco
    • A—HUMAN NECESSITIES
    • A24—TOBACCO; CIGARS; CIGARETTES; SIMULATED SMOKING DEVICES; SMOKERS' REQUISITES
    • A24C—MACHINES FOR MAKING CIGARS OR CIGARETTES
    • A24C5/00—Making cigarettes; Making tipping materials for, or attaching filters or mouthpieces to, cigars or cigarettes
    • A24C5/32—Separating, ordering, counting or examining cigarettes; Regulating the feeding of tobacco according to rod or cigarette condition
    • A24C5/34—Examining cigarettes or the rod, e.g. for regulating the feeding of tobacco; Removing defective cigarettes
    • A24C5/3412—Examining cigarettes or the rod, e.g. for regulating the feeding of tobacco; Removing defective cigarettes by means of light, radiation or electrostatic fields

Definitions

  • This invention relates to a method for determining the moisture content in tobacco in particulate form.
  • the invention also relates to apparatus suitable for use in determining the attenuation of microwave energy by tobacco in particulate form.
  • the moisture content of the tobacco is an important variable which should be controlled within narrow tolerances during the various stages of manufacture.
  • the problem of controlling the moisture in tobacco is made more dicult because tobacco is hygroscopic.
  • the tobacco is able to pick up moisture from the air very readily and thus disturb the balance achieved by previous careful attention to the water content.
  • a method of measuring moisture for the tobacco industry must provide reproduceable accurate results. If the precision of the method is poor, control of moisture content within narrow tolerances will not be possible.
  • the reproducibility depends on two factors-first, the reproducibility of the actual measurements; and second, the reproducibility of the sample.
  • the sample to be tested be selected in a certain manner, and handled in a certain manner during the measurement.
  • microwave energy measurement techniques are eminently suited for determining the moisture content of tobacco in particulate form, (for example shredded tobacco or strip tobacco) provided certain procedures and apparatus are employed.
  • Another object of this invention is to provide an improved apparatus suitable for measuring the attenuation of microwave energy caused by passage through a sample of tobacco in particulate form, the improvement in said apparatus relating to electronic reproducibility due t0 elimination of variables such as reflectance.
  • a further object of this invention is to provide an improved sample holder for use in measuring the attenuation of microwave energy.
  • An additional object of this invention is to provide a method of determining the moisture content of tobacco in particulate form ⁇ by concurrently measuring the attenuation of microwave energy caused by passage through a sample of the tobacco and the temperature of tobacco sample.
  • Another object of this invention is to provide a method of determining the moisture content of tobacco in particulate form which involves the use of a sample of .tobacco of a uniform weight, vibrating the sample to ice eliminate non-uniformities in packing, and compressing the sample prior to measuring the attenuation of micro- Wave energy caused by passage through the sample.
  • one embodiment of this invention provides an improvement in an apparatus for measuring attenuation of energy in the microwave frequency range of the electromagnetic spectrum caused by passage of said energy -through a sample, the apparatus comprising a source of microwave energy tuned to a specific frequency, a transmit-ting horn connected to said source for beaming the microwave energy at said sample, a receiving horn aligned with said transmitting horn and positioned to receive the microwave energy transmitted by the sample, and means connected to said receiving horn for determining the attenuation caused by said sample, ⁇ the said improvement comprising a sample holder in the shape of a hollow cylinder, they wall of said sample holder being constructed of Va material which is electrically conductive, one end of said sample holder being sealed with a disc which is perpendicular to the cylindrical axis of said holder and which has a thickness of 1/2 wave length of the said specific frequency of the microwave energyr source, said disc being transparent to microwave energy, the other end of said holder being adapted to receive and position an internally fitting cap, said cap comprising
  • FIG. 1 is a schematic view showing the relationship of the electronic components suitable for use in one embodiment of the present invention
  • FIG. 2 is a perspective view of the sample holder of the present invention and the positioning means and other elements associated therewith in accordance with one ernbodiment of this invention
  • FIG. 3 is a sectional view of FIG. 2 along the line 3--3 therein,
  • FIG. 4 is a sectional View of FIG. 3 along the line 4 4 therein, and
  • FIG. 5 is an exploded perspective view of one embodiment of the sample holder of this invention.
  • FIG. 1 there is depicted the various electronic com- .'35 ponents conventionally employed for measuring microwave energy attenuation.
  • FIG. 1 Shown in FIG. 1 is a klystron microwave oscillator 10 which produces energy in the microwave region.
  • Modulated power supply 11 furnishes the required operating voltages for oscillator 10, and also provides a modulating voltage which causes the amplitude of the output of oscillator to vary at a frequency in the audio range.
  • the oscillator is of the type whose frequency is adjustable in the range of approximately 8,000 to 12,000 megacycles.
  • the microwave energy from oscillator 10 is introduced into ferrite isolator 12 which serves as a unidirectional element.
  • Attenuator 13 is utilized for precisely controlling the amplitude of the microwave energy.
  • the energy leaving attenuator 13 is introduced into a microwave antenna or horn 14 which focuses the energy into a beam.
  • Sample holder 15 is shown in the -drawings as being positioned to receive the energy transmitted by horn 14. The details of holder 15 will be described below.
  • sample holder 15 contains a material which absorbs microwave energy, the beam of energy leaving holder 15 will be correspondingly reduced. The energy which leaves holder 15 is collected by another microwave antenna or horn 16.
  • the energy collected by horn 16 is introduced into precision attenuator 17.
  • the purpose of attenuator 17 will be described shortly.
  • the energy leaving attenuator 17 is introduced into crystal detector 18 which rectifes the alternating input and provides an output which pulsates at the audio frequency at which oscillator 10 is modulated.
  • the signal produced by detector 18 is amplified by tuned audio amplier 1'9, and the output of amplier 19 is introduced into meter for visual observation.
  • FIG. 1 The various components shown in FIG. 1 are, of course, connected by conventional wave guide sections.
  • Attenuator 17 is adjusted so that it causes a predetermined amount of attenuation on the energy introduced therein. With the sample holder 15 absent, attenuator 13 is adjusted to provide full scale deflection on meter 20.
  • amplifier 19 is provided with a gain adjustment and this is used to correct for the aging of electronic components therein, meter departures and the like.
  • a sample of the material to be tested is introduced into holder 15, and holder 15 is then inserted lbetween horns 14 and 16. Assuming that the material in holder 15 is capable -of absorbing microwave energy, the indicator of meter 20 will drop from its previous full scale reading, thus indicating that the energy reaching it is lower than the calibration level. At this point, attenuator 17 is adjusted to decrease the amount of attenuation caused thereby, and this adjustment is continued until the indicator of meter 20 is again at its full scale position. At this point, the attenuation caused by absorption of microwave energy by the sample in holder 15 has been exactly offset by the decrease in attenuation caused by attenuator 17. Attenuator 17 is provided with an accurately calibrated dial so that the change in setting can be easily determined. This change in setting of the dial of attenuator -17 then represents the attenuation caused -by absorption of microwave energy -by the sample in holder 15.
  • the deflection of the needle of meter 20 can be used as a measure of the attenuation caused by the sample in holder 15.
  • this is undesirable since the reading would be subject to errors and variations from many sources, such as non-linearity in detector 18 and/or amplier 19 and the like.
  • attenuator 17 By using attenuator 17 to increase the energy fed to crystal detector 18, all of the components following attenuator 17 are returned to the datum level which prevailed under calibration conditions.
  • the present invention provides a method of determining the moisture content of tobacco in particulate form which has proven to be reliable, reproduceable and accurate.
  • the advantages of the present invention stem from certain operational steps employed in the actual determination of the attenuation, and also from the manner in which the tobacco sample is formed.
  • a novel sample holder has been developed which enhances the accuracy of the method of the invention.
  • FIG. 2 is a perspective view showing sample holder 15, and its relationship to the other elements of the invention.
  • FIG. 2 shows a supporting structure 21 in which are positioned horns 14 and 16.
  • Holder 15 is shown in detail in FIG. 5.
  • Hollow cylinder 22 is provided to hold the sample of tobacco.
  • it is constructed from an electrically conductive material to prevent the escape of any microwave energy through the walls.
  • a disc 23 of material transparent to microwave energy is used as a seal for end 24 of cylinder 22. It is conveniently attached by screws (not shown) which engage the wall of cylinder 22, and screw holes 25 are depicted in disc 23 for this purpose.
  • holder 15 is designed to admit cap 26, discussed in detail below. To this end, the inside diameter of the terminal portion 46 of holder 15 has been enlarged thereby forming shoulder 47.
  • Cap 26 is cylindrical in shape and has two portions of differing diameter, the elongated portion 27 having an outside diameter approximately equal to the diameter of terminal portion 46 of cylinder 22 thereby permitting it to be inserted therein.
  • the wall thickness of portion 27 of cap 26 is made equal to the width of shoulder 47.
  • the larger diameter portion 2.8 of cap 26 in conjunction with shoulder 47 serves as a stop which prevents further movement of portion 27 into the interior of cylinder 22.
  • a disc 29 of material transparent to microwave radiation is attached to the end 30 of cap 26 and serves as a seal.
  • FIG. 4 is a sectional view showing holder 15 with cap 26 in place.
  • locking means are provided.
  • these locking means are raised catch 31 which is attached to the periphery of cylinder 22, and latch 32 which is attached to the periphery of portion 28 of cap 26. Since catch 31 is partially spaced from the surface of cylinder 22, latch 32 slides thereunder in frictional engagement therewith. This relationship is best seen in FIG. 2.
  • Holder 15 is provided with handles 33 having slots 34 therein to facilitate handling cylinder 22.
  • Handles 33 also function as guide means. As shown vin thevdrawings,lthere is a V-shaped slot 36 cut in each of the handles 33. Inverted V-shaped blocks 37 are attached to structure 21, as shown in FIG. 2. When the holder 15 is introduced between horns 14 and 16, V-
  • FIG. 2 there is depicted a pair of resilient bumpers 38 which are connected toy structure 21. These bumpers serve to maintain holder 15 rmly in place.
  • Blocks 39 are attached to structure 21 and serve as stops to align holder 15 with the apertures 40 and 41 of horns 1-4 and 16, respectively.
  • FIG. 1 schematically depicts temperature indicator 42 which is connected to temperature probe 43. These are provided in order to enable a temperature measurement to be made simultaneously with the attenuation measurement.
  • FIGS. 2 and 3 illustrate the location of temperature probe 43 with respect to the other elements of the apparatus.
  • the longitudinal axis of probe 43 should be oriented parallel to the magnetic vector of the microwave energy.
  • Temperature probe 43 is a fast-response probe having a tip 45 which comprises a temperature-sensitive thermistor.
  • holder 15 is provided with an opening 44 which is adapted to receive temperature probe 43.
  • opening 44 is positioned to admit temperature probe 43.
  • FIG. 3 illustrates probe 43 in position within holder 15.
  • the temperature sensed by probe 43 is displayed on temperature indicator 42, shown schematically in FIG. l.
  • a temperature calibration chart of temperature versus moisture correction factor may be obtained as follows. Samples of tobacco are prepared having various moisture levels. Microwave attenuation measurements in accordance with the procedure outlined herein are then made on the tobacco samples at different temperatures. The amount of moisture in the tobacco samples is determined beforehand by quantitative analysis. Then, a group of data are obtained showing the variations in microwave attenuation for a sample of Agiven moisture content when measured at various temperature-s. In this manner, a family of curves of attenuation versus moisture content at specific temperatures may be constructed.
  • the preferred method of measuring the moisture in tobacco in particulate form comprises several steps. First, a standard weight of sample is utilized. This standard weight should have a volume which will approximately fill -holder 15. In other words, holder 15 is placed in an upright position with disc 23 on the bottom and with cap 26 removed. The particulate tobacco is then introduced into holder 15, the preweighed sample substantially lling the holder.
  • .holder 15 be mounted on a vibrating surface, 'such as a conventional vibrating table during the filling operation. In this manner the tendency toward a non-homogenous sample structure is avoided.
  • the sample within holder 15 is then compressed by placing cap 26 in its proper position within holder 15. As can be seen in FIG. 4, when cap 26 is positioned properly Within holder 15, disc 29 extends partially into the interior of holder 15. Thus the sample volume is compressed in proportion to the relative dimensions of holder 15 and elongated portion 27 of cap 26. The compression of the sample is considered to aid in the reproducibility of attenuation measurements made in accordance with the method of the present invention.
  • the filled sample holder 15 is then introduced between transmitting horn 14 and receiving lhorn 16, as shown in FIG. 2.
  • the V-shaped slots 36 in handle 33 engage inverted V-shaped blocks 37, and thus in conjunction with bumpers 38 and blocks 39 serve to reproduceably position holder 15 between horns 14 and 16.
  • the attenuation measurement is made as described above and the temperature measurement is made, and compensation provided, if necessary.
  • the setting of the dial of attenuator 17 is preferably utilized as a measure of the attenuation caused by the sample.
  • the dial of attenuator 17 may be designed so as to read directly in moisture content.
  • a potential source of error in measuring attenuation with the apparatus described herein is from the non-reproducibility of reected microwave energy.
  • disc 23 of holder 15 and disc 29 of cap 26 are designed to have a thickness of one-half of a wavelength (in the dielectric material of which the discs are formed) of the specific frequency being utilized.
  • the respective apertures of horns 14 and 16 are chosen to be approximately equal to the inside diameter of sample holder 15. This provides a narrow or parallel beam so that substantially all of the microwave energy emanating from transmitting horn 14 must pass through the sample in sample holder 15.
  • the shape of the sample holder and the relative dimensions thereof are also factors which are important in obtaining accurate att-enuation measurements.
  • a cylindrical sample holder is preferred to one which is square, for example, because the cylindrical holder can be more readily packed in a uniform manner.
  • the square corners of ⁇ a square cross-sectioned holder would tend to cause irregularities and non-uniformities in and about the corners, and therefore some degree of reproducibility would
  • sample holder 15 should have a length which is greater than its diameter. If it could be assured that each sample would have an ideally uniform structure, i.e. be completely homogenous, then the relative dimensions of the holder would be 'of no importance. The above choice of relative dimensions of holder 15 is based on the supposition that it is not possible to achieve cornplete uniformity or homogeneity in the sample.
  • Each molecule of water present in the sample has a capacity of absorbing microwave energy.
  • the particulate tobacco may be present in stratifying 'layers which are perpendicular to the path of the microwave energy.
  • Each of these layers is assumed to be completely uniform but each layer differs in density from each succeeding layer.
  • the second non-uniform condition would be one in which the packing is uniform in any one path through sample holder 15, parallel to the beam of microwave energy, but each such path has a different packing density from each other. Simply, this could be illustrated by assuming that half of the interior of holder 15, sliced longitudinally, has one density ⁇ and the other half has a second, different density. In such instance, the attenuation measured would not be the true average attenuation.
  • a holder for the sample of tobacco comprising:
  • suppport means for supporting said holder spaced between said horns without physical cont-act between said holder and said horns.
  • the holder of claim 1 further characterized by: the axial length of said cylinder being greater than the diameter of said cylinder.
  • the holder of claim 1 ⁇ further characterized by: means zfor compressing by a predetermined amount whatever particulate matter may be placed in said cylinder.
  • the holder of claim 1 further characterized by: a temperature sensing probe extending through said cy-linder wall, the axis of said probe being perpendicular to the axis of said cylinder.
  • a holder for the sample of tobacco comprising:
  • the holder of claim 5 further characterized by: the axial length of said cylinder being greater than the diameter of said cylinder.
  • the holder of claim 5 further characterized by: a temperature sensing probe extending through said cylinder wall, the axis of said probe being perpendicular to the axis ⁇ of said cylinder.

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  • Physics & Mathematics (AREA)
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  • Life Sciences & Earth Sciences (AREA)
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  • Biochemistry (AREA)
  • General Physics & Mathematics (AREA)
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  • Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
US320015A 1963-10-30 1963-10-30 Determination of moisture in tobacco Expired - Lifetime US3360721A (en)

Priority Applications (5)

Application Number Priority Date Filing Date Title
US320015A US3360721A (en) 1963-10-30 1963-10-30 Determination of moisture in tobacco
DE19641498863 DE1498863A1 (de) 1963-10-30 1964-10-28 Verfahren und Vorrichtung zur Bestimmung des Feuchtigkeitsgehaltes in Tabak
GB44251/64A GB1028720A (en) 1963-10-30 1964-10-29 Method and apparatus for determining moisture in tobacco
CH1404864A CH426591A (fr) 1963-10-30 1964-10-30 Procédé pour déterminer la teneur en humidité d'un tabac en particules et appareil pour sa mise en oeuvre
BE655112D BE655112A (fr) 1963-10-30 1964-10-30

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CH (1) CH426591A (fr)
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GB (1) GB1028720A (fr)

Cited By (16)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3501692A (en) * 1966-08-17 1970-03-17 Hammtronics Systems Inc Apparatus for determining the moisture content of solids and liquids
US4326542A (en) * 1980-01-14 1982-04-27 Philip Morris Incorporated Firmness control in a cigarette maker
US4490676A (en) * 1981-12-31 1984-12-25 Texaco Inc. Microwave means for monitoring fluid in a core of material
EP0040805B1 (fr) * 1980-05-23 1985-04-17 Philip Morris Incorporated Méthode pour la mesure de l'humidité d'un matériau
US4707652A (en) * 1983-11-30 1987-11-17 Philip Morris Incorporated Impurity detector measuring parallel polarized scattered electromagnetic radiation
US5046356A (en) * 1988-09-28 1991-09-10 Kanzaki Paper Manufacturing Co., Ltd. Apparatus for determining water content of powder/granule
WO1996032633A1 (fr) * 1995-04-13 1996-10-17 Institut National Polytechnique De Toulouse (Inpt) Dispositif de mesure du taux d'humidite d'un materiau granulaire
US5621330A (en) * 1995-07-18 1997-04-15 Malcam Ltd. Device and method for determining the moisture content of a bale of material with multiple layers
US5714887A (en) * 1996-05-10 1998-02-03 New Holland North America, Inc. Fixture for use in microwave grain moisture measurement
US5845529A (en) * 1995-07-18 1998-12-08 Malcam Ltd. Device and method for determining the moisture content of material
US6025724A (en) * 1997-11-20 2000-02-15 Malcam Ltd. Device and method for determining the moisture content of packaged material
US6111415A (en) * 1998-01-09 2000-08-29 Malcam Ltd. Device and method for determining the moisture content of a bulk material
FR2849201A1 (fr) * 2002-12-18 2004-06-25 Tabacs & Allumettes Ind Porte-echantillon pour la mesure du tirage et de l'humidite d'objets poreux
CN110596152A (zh) * 2019-09-16 2019-12-20 安徽大洋自动化科技有限公司 一种粮食水分容重智能检测装置
EP3928638A3 (fr) * 2015-06-05 2022-05-04 Hulecos SA Dispositif d'analyse pour un article à fumer individuel
CN116148279A (zh) * 2023-03-17 2023-05-23 湖北中烟工业有限责任公司 一种加热卷烟烟丝水分测定方法

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2048492B (en) * 1979-04-11 1983-03-30 British American Tobacco Company Ltd Improvements relating to the measurement of moisture content
CN110286199B (zh) * 2019-06-17 2021-09-21 云南中烟工业有限责任公司 一种基于叶丝水分蒸发焓评价滚筒干燥过程叶丝加工强度一致性的方法

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US2082364A (en) * 1933-12-19 1937-06-01 Arthur O Store Moisture tester
GB592450A (en) * 1945-03-14 1947-09-18 Marconi Instruments Ltd Apparatus for determining the moisture content of materials
US2581950A (en) * 1948-07-28 1952-01-08 Square Grip Reinforcement Comp Method and apparatus for determining water content of concrete in the fluid state
US2611804A (en) * 1948-01-28 1952-09-23 Gen Precision Lab Inc Measuring apparatus
US2613251A (en) * 1947-02-11 1952-10-07 Polytechnic Inst Brooklyn Resistance comparator
US2659860A (en) * 1949-08-27 1953-11-17 Inst Textile Tech Method and apparatus for measuring moisture content
FR1102199A (fr) * 1954-04-02 1955-10-18 Centre Nat Rech Scient Procédé et dispositifs pour la détermination de la teneur en eau et des proportions d'eau liée et d'eau libre contenues dans diverses substances
US2724798A (en) * 1952-01-26 1955-11-22 Beckman Instruments Inc Apparatus for measuring characteristics of materials
US2755438A (en) * 1953-03-11 1956-07-17 William H Cudmore Moisture tester for grains
US2798197A (en) * 1953-11-16 1957-07-02 Shell Dev Microwave bridge
US3115131A (en) * 1961-10-16 1963-12-24 Reuben H Holliday Microwave absorption measurement

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2082364A (en) * 1933-12-19 1937-06-01 Arthur O Store Moisture tester
GB592450A (en) * 1945-03-14 1947-09-18 Marconi Instruments Ltd Apparatus for determining the moisture content of materials
US2613251A (en) * 1947-02-11 1952-10-07 Polytechnic Inst Brooklyn Resistance comparator
US2611804A (en) * 1948-01-28 1952-09-23 Gen Precision Lab Inc Measuring apparatus
US2581950A (en) * 1948-07-28 1952-01-08 Square Grip Reinforcement Comp Method and apparatus for determining water content of concrete in the fluid state
US2659860A (en) * 1949-08-27 1953-11-17 Inst Textile Tech Method and apparatus for measuring moisture content
US2724798A (en) * 1952-01-26 1955-11-22 Beckman Instruments Inc Apparatus for measuring characteristics of materials
US2755438A (en) * 1953-03-11 1956-07-17 William H Cudmore Moisture tester for grains
US2798197A (en) * 1953-11-16 1957-07-02 Shell Dev Microwave bridge
FR1102199A (fr) * 1954-04-02 1955-10-18 Centre Nat Rech Scient Procédé et dispositifs pour la détermination de la teneur en eau et des proportions d'eau liée et d'eau libre contenues dans diverses substances
US3115131A (en) * 1961-10-16 1963-12-24 Reuben H Holliday Microwave absorption measurement

Cited By (21)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3501692A (en) * 1966-08-17 1970-03-17 Hammtronics Systems Inc Apparatus for determining the moisture content of solids and liquids
US4326542A (en) * 1980-01-14 1982-04-27 Philip Morris Incorporated Firmness control in a cigarette maker
EP0040805B1 (fr) * 1980-05-23 1985-04-17 Philip Morris Incorporated Méthode pour la mesure de l'humidité d'un matériau
US4490676A (en) * 1981-12-31 1984-12-25 Texaco Inc. Microwave means for monitoring fluid in a core of material
US4707652A (en) * 1983-11-30 1987-11-17 Philip Morris Incorporated Impurity detector measuring parallel polarized scattered electromagnetic radiation
US5046356A (en) * 1988-09-28 1991-09-10 Kanzaki Paper Manufacturing Co., Ltd. Apparatus for determining water content of powder/granule
WO1996032633A1 (fr) * 1995-04-13 1996-10-17 Institut National Polytechnique De Toulouse (Inpt) Dispositif de mesure du taux d'humidite d'un materiau granulaire
FR2733051A1 (fr) * 1995-04-13 1996-10-18 Toulouse Inst Nat Polytech Dispositif de mesure du taux d'humidite d'un materiau, en particulier de produits agricoles se presentant sous forme de grains ou graines
US5845529A (en) * 1995-07-18 1998-12-08 Malcam Ltd. Device and method for determining the moisture content of material
US5621330A (en) * 1995-07-18 1997-04-15 Malcam Ltd. Device and method for determining the moisture content of a bale of material with multiple layers
US5714887A (en) * 1996-05-10 1998-02-03 New Holland North America, Inc. Fixture for use in microwave grain moisture measurement
US6025724A (en) * 1997-11-20 2000-02-15 Malcam Ltd. Device and method for determining the moisture content of packaged material
US6111415A (en) * 1998-01-09 2000-08-29 Malcam Ltd. Device and method for determining the moisture content of a bulk material
FR2849201A1 (fr) * 2002-12-18 2004-06-25 Tabacs & Allumettes Ind Porte-echantillon pour la mesure du tirage et de l'humidite d'objets poreux
WO2004065948A3 (fr) * 2002-12-18 2004-10-28 D Expl Des Tabacs Et Allumette Porte-echantillon pour la mesure du tirage et de l'humidite d'objets poreux
US20060102730A1 (en) * 2002-12-18 2006-05-18 Societe Nationale D'exploitation Industrielle Des Tabacs Et Allumettes (S.E.I.T.A.) Sample-holder for measuring draft and moisture in porous objects
EP3928638A3 (fr) * 2015-06-05 2022-05-04 Hulecos SA Dispositif d'analyse pour un article à fumer individuel
US11583000B2 (en) 2015-06-05 2023-02-21 Preciflex Sa Devices for active humidification and flavouring
CN110596152A (zh) * 2019-09-16 2019-12-20 安徽大洋自动化科技有限公司 一种粮食水分容重智能检测装置
CN110596152B (zh) * 2019-09-16 2024-02-20 安徽大洋自动化科技有限公司 一种粮食水分容重智能检测装置
CN116148279A (zh) * 2023-03-17 2023-05-23 湖北中烟工业有限责任公司 一种加热卷烟烟丝水分测定方法

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Publication number Publication date
DE1498863A1 (de) 1969-04-17
BE655112A (fr) 1965-04-30
CH426591A (fr) 1966-12-15
GB1028720A (en) 1966-05-04

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