US3668928A - Non-destructive hardness, testing of articles such as cigarettes - Google Patents
Non-destructive hardness, testing of articles such as cigarettes Download PDFInfo
- Publication number
- US3668928A US3668928A US37272A US3668928DA US3668928A US 3668928 A US3668928 A US 3668928A US 37272 A US37272 A US 37272A US 3668928D A US3668928D A US 3668928DA US 3668928 A US3668928 A US 3668928A
- Authority
- US
- United States
- Prior art keywords
- article
- space
- chamber
- suction
- 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
Links
- 235000019504 cigarettes Nutrition 0.000 title claims abstract description 39
- 238000012360 testing method Methods 0.000 title claims description 8
- 239000000463 material Substances 0.000 claims description 4
- 238000007789 sealing Methods 0.000 claims description 2
- 238000011068 loading method Methods 0.000 abstract description 8
- 241000208125 Nicotiana Species 0.000 description 4
- 235000002637 Nicotiana tabacum Nutrition 0.000 description 4
- 238000005259 measurement Methods 0.000 description 3
- 238000000034 method Methods 0.000 description 3
- 230000006835 compression Effects 0.000 description 2
- 238000007906 compression Methods 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 101100440640 Drosophila melanogaster conu gene Proteins 0.000 description 1
- 208000036366 Sensation of pressure Diseases 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 230000001066 destructive effect Effects 0.000 description 1
- 238000007542 hardness measurement Methods 0.000 description 1
- 238000003780 insertion Methods 0.000 description 1
- 230000037431 insertion Effects 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- 239000003643 water by type Substances 0.000 description 1
Images
Classifications
-
- 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
- A24C5/3418—Examining cigarettes or the rod, e.g. for regulating the feeding of tobacco; Removing defective cigarettes by pneumatic means
Definitions
- the applicant now proposes a method and apparatus which does not rely on liquid pressure or on the measurement of a small volume of gas expelled from a cigarette.
- a method according to the invention comprises applying a first pressure to the outer covering and recording that pres sure; establishing and recording the diameter of the article at the first pressure as a first diameter; pneumatically compressing the article at a second pressure higher than the first pressure and recording the second pressure;
- the heart of the unit consists of a series of rings 4 adapted to surround a cigarette 3. Alternate sides of the rings 4 are connected to a chamber 2 and to a chamber 25 which is at atmospheric pressure through a port 26.
- the cigarette is held in position by means of a thin rubber tube 24 which is stretched to such an extent that its inside diameter is smaller than that of the cigarette 3.
- a plug 5 seals the cigarette 3 from atmosphere and at the other side a tube 6 connects the inside of the cigarette 3 to a suction system.
- the chamber 2 is connected to a vacuum pump 12 through a critical flow orifice l0 and a shut-off valve 11.
- the vacuum pump 12 provides suction of at least 0.6 Kp/cm.
- a transducer 7 measures pressure in the chamber 2 which is a function of the diameter of the cigarette 3.
- a transducer 8 measures the suction applied to the cigarette. Transducers 7 and 8 can be sampled by a scanner/digital voltmeter 9.
- each of the rings 4 forms such an annulus. Since there are several rings 4 (four in the illustrated embodiment) the pressure reading in the chamber 2 is a measure of the diameter of the tube 24 as averaged over those several diameters that are surrounded by the rings 4.
- Shut-oil valves 14 and 15 connect the cigarette interior to suction chambers and 21. Suction in chambers 20 and 21 is maintained at approximately -0.l and 0.4 Kp/cm respectively by means of control valves 17 and l8.
- test sequence is as follows:
- D! and D2 are taken at pressure above a PO which is equal to the pressure exerted by the tobacco on the paper wall.
- hardnessll-P may be computed by utilising the formula:
- the tube 24 is not essential for a measure of hardness to be obtained. However, if the tube 24 be not used, the porodty of the cigarette paper will afl'ect the measurements and these will have to be adjusted accordingly. In view of the absence of these adjustments when a tube is used, it is preferred to use the apparatus with the tube 24.
- Apparatus for testing a cylindrical article such as a cigarette comprising a filling material and an outer covering comprising:
- a chamber surrounding the article and at least one ring the chamber dividing the chamber into two compartments, the ring surrounding the article with an annular gap between it and the article;
- the apparatus claimed in claim 1 including a gee-imperviour sheath for clrcumferentlally enclosing the article the gap being between the ring and the sheath.
- a chamber having two end walls connected by side walls an opening in the side walls a shut off valve for controlling the opening regiltering borer in the end walls means for applying suction to the first space in the chamber; Mr M 7 W m. means for applying suction to the second space in the chamber; a critical flow orifice connected between the latter suction means and the second space meansformeasuringthepressureinthesecondapacemnd means for measuring the suction applied to the other end of the tube.
Landscapes
- Manufacturing Of Cigar And Cigarette Tobacco (AREA)
- Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)
Abstract
A cigarette is tested for hardness by inserting it into a rubber sleeve which is surrounded by rings. Air is passed through the annuli formed between the cigarette and the rings. The pressure drop is measured firstly with the cigarette interior as is, secondly with the cigarette interior subjection to a first suction and thirdly with the interior subjected to a second suction. The pressure drops are measures of the diameters of the cigarette at the various interior loadings. From these diameters and the loadings the hardness of the cigarettes may be computed.
Description
United States Patent Strydom 1 NON-DESTRUCTIVE HARDNESS,
TESTING OF ARTICLES SUCH AS CIGARETTES [72] Inventor: Mauritz Leon Strydom, Stellenbosch.
South Africa [73] Assignee: Tobacco Research and Development Institute Limited 22] Filed: May 14, 1970 [2]] Appl.No.: 37,272
[30] Foreign Application Priority Data Oct. I5, 1969 South Africa ..69/72$9 May 16, 1969 South Africa. ..69/3457 [52] U.S. Cl ..73/78, 73/37.5, 73/38 [51] lnLCl ..G0ln 3/10,G0lb 13/08 [58] FieldoiSenrch ..73/78, 37.5, 37.8, 37.9, 94, 73/38 [l5] 3,668,928 51 June 13, 1972 i References Cited UNITED STATES PATENTS 2,976,7l8 3/196] Baker ..73/37.$ 3,115,772 I2 963 O'Keefe et a]. ...73/78 X 3,438,250 4/]969 Boutron r ..73/94 3,559,466 2/197] Calleson ..73/94 X Primary xaminerRichard C. Oueisser Assistant Emminer-Ellis J. Koch Attorney-Waters, Roditi, Schwartz & Nissen ABSTRACT A cigarette is tested for hardness by inserting it into a rubber sleeve which is surrounded by rings. Air is passed through the annuli formed between the cigarette and the rings. The pressure drop is measured firstly with the cigarette interior as is, secondly with the cigarette interior subjection to a first suction and thirdly with the interior subjected to a second suction. The pressure drops are measures of the diameters of the cigarette at the various interior loadings. From these diameters and the loadings the hardness of the cigarettes may be computed.
6 Claims, 1 Drawing Figure PAIENTEum 13 m2 NON-DESTRUCTIVE HARDNESS. TESTING OF ARTICLES SUCH AS CIGARETTE This invention relates to the non-destructive hardness testing of articles such as cigarettes.
Conventional hardnes testers measure the depth to which a plunger acting under a predetermined force dents the periphery of a cigarette. The depth of the dent is some inverse function of the true hardness expressed in gin/mm. instrw ments which are able to give a reliable measure of the hardness of cigarettes by the conventional method are highly sophisticated and therefore expensive. A method of making and measuring dens caused by gas flow is described in U.S. Pat. No. 3,411,5l3.
In U.S. Pat. No. 3,1l5,772 it has been proposed to insert a cigarette into a sleeve, to apply pressure by liquid means to the sleeve and to measure the volume of gas expelled from the cigarette. The ratio of the volume before compression and the volume after compression is said to be a measure of the "firmness" of the cigarette. The term firmness as used in the U.S. specification and the term "hardness" used in this specification are interchangeable.
The applicant now proposes a method and apparatus which does not rely on liquid pressure or on the measurement of a small volume of gas expelled from a cigarette.
A method according to the invention comprises applying a first pressure to the outer covering and recording that pres sure; establishing and recording the diameter of the article at the first pressure as a first diameter; pneumatically compressing the article at a second pressure higher than the first pressure and recording the second pressure;
establishing and recording the diameter of the article at the second pressure as a second diameter; and
deriving a measure of a property of the article from the diameters and pressures thus recorded.
The invention is further discussed with reference to the accompanying drawing which is a schematic representation of apparatus suitable for carrying out the method of the inven tion with the main component in section.
The heart of the unit consists of a series of rings 4 adapted to surround a cigarette 3. Alternate sides of the rings 4 are connected to a chamber 2 and to a chamber 25 which is at atmospheric pressure through a port 26. The cigarette is held in position by means of a thin rubber tube 24 which is stretched to such an extent that its inside diameter is smaller than that of the cigarette 3.
A plug 5 seals the cigarette 3 from atmosphere and at the other side a tube 6 connects the inside of the cigarette 3 to a suction system.
The chamber 2 is connected to a vacuum pump 12 through a critical flow orifice l0 and a shut-off valve 11. The vacuum pump 12 provides suction of at least 0.6 Kp/cm.
A transducer 7 measures pressure in the chamber 2 which is a function of the diameter of the cigarette 3. A transducer 8 measures the suction applied to the cigarette. Transducers 7 and 8 can be sampled by a scanner/digital voltmeter 9.
As a result of the inclusion of the critical flow orifice 10 in the circuit the rate of flow from the chamber 2 remains constant within wide limits regardless of the diameter of the tube 24 as long as there is clearance between the tube 24 and the rings 4.
it is well known to measure the diameter of an article by measuring the pressure drop in a gas flowing through an annulus formed aroung the article. in the present case each of the rings 4 forms such an annulus. Since there are several rings 4 (four in the illustrated embodiment) the pressure reading in the chamber 2 is a measure of the diameter of the tube 24 as averaged over those several diameters that are surrounded by the rings 4.
Shut-oil valves 14 and 15 connect the cigarette interior to suction chambers and 21. Suction in chambers 20 and 21 is maintained at approximately -0.l and 0.4 Kp/cm respectively by means of control valves 17 and l8.
'lheport26maybeclosedbymeansofavalve27actuated byapneumatlc cylinder-23fedwithcornpreaedairthrough valve22. Openingofthe valve 22cauaed the valve 27 locloee the port26. Closingofthe valve22allowstheport26toopen Ashut-oflvalve 13 controls theadmhaion ofsuction to the chamber 25. The-valve 13 leads to a suction chamber 19 the pressure of which is conu'olled by a valve 16. 'lhe pressure in thechamber Uissoregulatedthatwiththeportficloeedthe tube 24 is caused to stretch to a sufficient extent to allow for the insertion of a cigarette.
The test sequence is as follows:
Assume all shut-off valves closed. Open the valve 22. The cyIinderBisactivatedbycompressedairandthe port26is closed. Open the valve 13. The rubber tube 24 is expanded. lnsertacigarette,theplug5a.nd the tube6. Close Hand 22 sothattheport26isagainuncovered. lfthe valve ll is opened, the unloaded diameter DU can be obtained from the readingofthetransducerlonthe voltmeter! Openingthe valve 14 will cause a pressure load. of 0.1 Kp/cm' on the cigarette. The transducer 7 reads D1 and the transducer 8 reads Pl. likewise D2 and P2 are obtainable by closing the valve 14 and opening the valve 15.
Closing the valves 15 and 11 and opening the valves 22 and 13 will again open the tube 24, preparatory to replacing the cigarette with the next to be tested.
Note that D! and D2 are taken at pressure above a PO which is equal to the pressure exerted by the tobacco on the paper wall.
After correcting D1 and D2 by subtracting the thickness of the tube 24, hardnessll-P may be computed by utilising the formula:
H (P2-Pl) DU/ (DlD2) gin/mmwhere DU is the unloaded diameter P1 is the pressure of first loading P2 is the pressure of second loading D1 is the diameter under loading of?! D2 is the diameter under loading of P2 The pressure initially exerted by the tobacco on the paper wall may be computed as The hardness figure computed from measurements taken in the manner described above according to the above formula conforms very closely to figures determined by more conventional ways. In addition the figure of pressure exerted by the tobacco is very useful for comparison purposes during the control of cigarette manufacture.
Note that the tube 24 is not essential for a measure of hardness to be obtained. However, if the tube 24 be not used, the porodty of the cigarette paper will afl'ect the measurements and these will have to be adjusted accordingly. In view of the absence of these adjustments when a tube is used, it is preferred to use the apparatus with the tube 24.
I claim 1. Apparatus for testing a cylindrical article such as a cigarette comprising a filling material and an outer covering, comprising:
means for supporting the article;
means for fluid-tightly sealing olf one end of the article;
meam for applying suction to the outer end of the article;
a chamber surrounding the article and at least one ring the chamber dividing the chamber into two compartments, the ring surrounding the article with an annular gap between it and the article;
meam for causing gas to flow through the annular gap from one side of the ring to the other side of the ring;
meam for measuring the pressure difierence between both sides of the ring; and
means for measuring the suction applied to the other end of the article.
2. The apparatus claimed in claim 1 including a gee-imperviour sheath for clrcumferentlally enclosing the article the gap being between the ring and the sheath.
3. The apparatus claimed in claim 2 in which the sheath is held in the chamber and including means to clone the chamber 5 and means to apply auction to the chamber to allow the sheath to expand to accept an article.
4. The apparatus claimed in claim 1 in which there are a plurality of rings arranged so that in the case of each ring, gas flow is from a first space to a second enclosed space, the first space being open to atmosphere and including means for subjecting the second space to suction.
5. The apparatus claimed in claim 4 in which the second space is connected to the means for subjecting it to suction 6. Apparatus for testing a cylindrical article such as a cigarette comprising a filling material and an outer covering,
comprising a chamber having two end walls connected by side walls an opening in the side walls a shut off valve for controlling the opening regiltering borer in the end walls means for applying suction to the first space in the chamber; Mr M 7 W m. means for applying suction to the second space in the chamber; a critical flow orifice connected between the latter suction means and the second space meansformeasuringthepressureinthesecondapacemnd means for measuring the suction applied to the other end of the tube.
i t i 4 Q
Claims (6)
1. Apparatus for testing a cylindrical article such as a cigarette comprising a filling material and an outer covering, comprising: means for supporting the article; means for fluid-tightly sealing off one end of the article; means for applying suction to the outer end of the article; a chamber surrounding the article and at least one ring within the chamber dividing the chamber into two compartments, the ring surrounding the article with an annular gap between it and the article; means for causing gas to flow through the annular gap from one side of the ring to the other side of the ring; means for measuring the pressure difference between both sides of the ring; and means for measuring the suction applied to the other end of the article.
2. The apparatus claimed in claim 1 including a gas-impervious sheath for circumferentially enclosing the article the gap being between the ring and the sheath.
3. The apparatus claimed in claim 2 in which the sheath is held in the chamber and including means to close the chamber and means to apply suction to the chamber to allow the sheath to expand to accept an article.
4. The apparatus claimed in claim 1 in which there are a plurality of rings arranged so that in the case of each ring, gas flow is from a first space to a second enclosed space, the first space being open to atmosphere and including means for subjecting the second space to suction.
5. The apparatus claimed in claim 4 in which the second space is connected to the means for subjecting it to suction through a critical flow orifice.
6. Apparatus for testing a cylindrical article such as a cigarette comprising a filling material and an outer covering, comprising : a chamber having two end walls connected by side walls ; an opening in the side walls ; a shut off valve for controlling the opening ; registering bores in the end walls ; a cylindrical flexible gas-impervious sheath mounted between the bores and defining a tube between the end walls ; rings surrounding the tube and each spaced from the tube by an annular gap ; means for so connecting the rings that they divide the chamber into a first space into which the opening in the side walls leads and a second space communicating with the first space through the annular gaps ; means for plugging one end of the tube ; means for applying suction to the other end of the tube ; means for applying suction to the first space in the chamber ; means for applying suction to the second space in the chamber ; a critical flow orifice connected between the latter suction means and the second space ; means for measuring the pressure in the second space ; and means for measuring the suction applied to the other end of the tube.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| ZA693457 | 1969-05-16 | ||
| ZA697259 | 1969-10-15 |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| US3668928A true US3668928A (en) | 1972-06-13 |
Family
ID=27130993
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| US37272A Expired - Lifetime US3668928A (en) | 1969-05-16 | 1970-05-14 | Non-destructive hardness, testing of articles such as cigarettes |
Country Status (4)
| Country | Link |
|---|---|
| US (1) | US3668928A (en) |
| JP (1) | JPS5018079B1 (en) |
| FR (1) | FR2048437A5 (en) |
| GB (1) | GB1296788A (en) |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3955406A (en) * | 1973-06-12 | 1976-05-11 | Tobacco Research And Development Institute Limited | Non-destructive hardness testing of articles such as cigarettes |
| US4306445A (en) * | 1979-05-04 | 1981-12-22 | Hauni-Werke Korber & Co. Kg | Apparatus for testing groups of cigarettes or like rod-shaped articles |
| US4341109A (en) * | 1980-07-07 | 1982-07-27 | Eastman Kodak Company | Method and apparatus for determining cigarette filter rod pressure drop |
| US4543816A (en) * | 1983-04-30 | 1985-10-01 | Hauni-Werke Korber & Co. K.G. | Method and apparatus for monitoring the diameters of rod-shaped products of the tobacco processing industry |
| US4596134A (en) * | 1985-06-03 | 1986-06-24 | Eastman Kodak Company | Method and apparatus for simulating smoking through cigarette filter tips to determine percentage of collapse |
| US4660411A (en) * | 1985-05-31 | 1987-04-28 | Reid Philip L | Apparatus for measuring transmission of volatile substances through films |
| US5081863A (en) * | 1985-05-31 | 1992-01-21 | Modern Controls, Inc. | Apparatus for measuring transmission of volatile substances through films |
| US5372030A (en) * | 1993-09-15 | 1994-12-13 | The University Of Georgia Research Foundation, Inc. | Non-destructive firmness measuring device |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2976718A (en) * | 1956-03-09 | 1961-03-28 | Sheffield Corp | Gaging apparatus for dimensions and the like |
| US3115772A (en) * | 1958-11-04 | 1963-12-31 | Philip Morris Inc | Apparatus and method for measuring the compressibility of deformable objects |
| US3438250A (en) * | 1965-03-26 | 1969-04-15 | Seita | Process and device for measuring the compactness of compressible bodies and especially of cigarettes |
| US3559466A (en) * | 1968-06-07 | 1971-02-02 | Liggett & Myers Inc | Direct readout deflection meter |
-
1970
- 1970-05-14 US US37272A patent/US3668928A/en not_active Expired - Lifetime
- 1970-05-15 GB GB1296788D patent/GB1296788A/en not_active Expired
- 1970-05-15 FR FR7017922A patent/FR2048437A5/fr not_active Expired
- 1970-05-15 JP JP7041257A patent/JPS5018079B1/ja active Pending
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2976718A (en) * | 1956-03-09 | 1961-03-28 | Sheffield Corp | Gaging apparatus for dimensions and the like |
| US3115772A (en) * | 1958-11-04 | 1963-12-31 | Philip Morris Inc | Apparatus and method for measuring the compressibility of deformable objects |
| US3438250A (en) * | 1965-03-26 | 1969-04-15 | Seita | Process and device for measuring the compactness of compressible bodies and especially of cigarettes |
| US3559466A (en) * | 1968-06-07 | 1971-02-02 | Liggett & Myers Inc | Direct readout deflection meter |
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3955406A (en) * | 1973-06-12 | 1976-05-11 | Tobacco Research And Development Institute Limited | Non-destructive hardness testing of articles such as cigarettes |
| US4306445A (en) * | 1979-05-04 | 1981-12-22 | Hauni-Werke Korber & Co. Kg | Apparatus for testing groups of cigarettes or like rod-shaped articles |
| US4341109A (en) * | 1980-07-07 | 1982-07-27 | Eastman Kodak Company | Method and apparatus for determining cigarette filter rod pressure drop |
| US4543816A (en) * | 1983-04-30 | 1985-10-01 | Hauni-Werke Korber & Co. K.G. | Method and apparatus for monitoring the diameters of rod-shaped products of the tobacco processing industry |
| US4660411A (en) * | 1985-05-31 | 1987-04-28 | Reid Philip L | Apparatus for measuring transmission of volatile substances through films |
| US5081863A (en) * | 1985-05-31 | 1992-01-21 | Modern Controls, Inc. | Apparatus for measuring transmission of volatile substances through films |
| US4596134A (en) * | 1985-06-03 | 1986-06-24 | Eastman Kodak Company | Method and apparatus for simulating smoking through cigarette filter tips to determine percentage of collapse |
| US5372030A (en) * | 1993-09-15 | 1994-12-13 | The University Of Georgia Research Foundation, Inc. | Non-destructive firmness measuring device |
Also Published As
| Publication number | Publication date |
|---|---|
| DE2023457A1 (en) | 1970-11-19 |
| JPS5018079B1 (en) | 1975-06-26 |
| GB1296788A (en) | 1972-11-15 |
| FR2048437A5 (en) | 1971-03-19 |
| DE2023457B2 (en) | 1976-07-01 |
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