US3591944A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for detection of leaks in seals of packages
Assignee: Safeway Inc
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Filing: 1969-03-03
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Granted: 1971-07-13
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Expires: 1989-03-03
Abstract
Abstract A machine for forming and testing sealed packages from heatsealable packaging materials employs an apparatus for forming individual packaging trays for receiving the product to be packaged from a first continuously fed web of heat-sealable flexible packaging material. A second continuously fed web of heat-sealable packaging material is directed along a path parallel to the path of the first web and is partially heat sealable thereto to package the product. After partial sealing, each of the serially connected train of packages is connected in fluid communication with means for evacuating the ambient atmosphere therefrom and replacing the ambient atmosphere with a preservative atmosphere. The package is then sealed to prevent escape of the preservative atmosphere and transported along the machine, still in the package train, to automatic inspection apparatus. The inspection apparatus provides a first section for detecting leaks in the individual packages and a second section for marking defective packages. The sensing section includes a pressure chamber for each individual package and means for sensing gas of the preservative atmosphere or a tracer gas portion of the preservative atmosphere should the inspected package be leaking such gas and to develop a control signal when gas leakage is detected. The marking section includes apparatus for marking a defective package received from the sensing section. An electrical control circuit extends between the sensing and the marking section to provide operative control of the marking apparatus at a delayed time which permits the travel of a package from the sensing section of the packaging machine to the marking section of the machine. After inspection, the packages are separated and the unmarked packages are then prepared for shipment while the marked packages are diverted so that their products may be repackaged. Inasmuch as the packages may be scuffed or in other ways have the integrity of their seals weakened or broken, for example the package material may be burned by labelling techniques, the packages are placed in an overwrap carton and the carton is subjected to another pressure test prior to sealing whereupon detection of the preservative atmosphere will signal that the carton contains a leaky package or packages. Cartons containing only sealed packages may then be further packaged for shipment and cartons containing leaky packages may be diverted for testing of the individual packages.
Inventors
- 👤 Burdsal G Wilcox
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 00:13
CPC Classifications
G; G01; G01M; G01M3/00; G01M3/02; G01M3/04; G01M3/20; G01M3/22; G01M3/226; G01M3/229; B; B29; B29C; B29C65/00; B29C65/82; B29C65/8207; B29C65/8246; B29C66/00; B29C66/01; B29C66/05; B29C66/10; B29C66/11; B29C66/112; B29C66/1122; B29C66/40; B29C66/41; B29C66/43
Claims Analysis
Total Claims: 42
Claim 1
Independent Claim
140 words
A method of individually inspecting a plurality of serially connected packages for leaks as said packages are moved in sequence along a line comprising the steps of providing a selected atmosphere within each of the connected packages at a first position on the line and sealing the individual connected packages to prevent escape of the selected atmosphere, sensing for the presence of said selected atmosphere in the environment of a pressure external of each of the joined packages at a variance with their internal pressures as they reach a second position on the line, said step of sensing including generating a signal upon sensing of said selected atmosphere, and detecting said signal and indicating a defective one of the serially connected packages in response to detection of the signal as a defective package reaches a third position on the line.
Claim 2
Independent Claim
140 words
A method of individually inspecting a plurality of serially connected packages for leaks as said packages are moved in sequence along a line comprising the steps of providing a selected atmosphere within each of the connected packages at a first position on the line and sealing the individual connected packages to prevent escape of the selected atmosphere, sensing for the presence of said selected atmosphere in the environment of a pressure external of each of the joined packages at a variance with their internal pressures as they reach a second position on the line, said step of sensing including generating a signal upon sensing of said selected atmosphere, and detecting said signal and indicating a defective one of the serially connected packages in response to detection of the signal as a defective package reaches a third position on the line.
Claim 3
Dependent Claim
26 words
The method according to claim 1, wherein said step of providing a selected atmosphere is further defined as mixing a preservative gas with a tracer gas.
Claim 4
Dependent Claim
208 words
Packaging apparatus comprising means for transporting a first sheet of packaging material along a first path, means disposed along said first path for forming trays in the packaging material for receiving a product, means for transporting a second sheet of packaging material along a second path including a path portion parallel to the first path, first sealing means for sealing the first and second sheets of material together around the periphery of each of said trays, said first sealing means leaving an unsealed portion in the periphery of each of said trays to form partially sealed packages, means for evacuating the partially sealed packages, means for injecting a selected gas into the partially sealed packages; second sealing means for sealing the unsealed portions of said packages to prevent escape of said selected gas, means disposed along said first path and downstream of said second sealing means for providing a pressure external of the sealed packages which is at a variance with the internal pressure of the packages, including detecting means operable to generate a leak detection signal upon detection of the selected gas, and indicating means disposed adjacent said first path and connected to said detecting means and operated by a leak detection signal to indicate defective packages.
Claim 5
Dependent Claim
208 words
Packaging apparatus comprising means for transporting a first sheet of packaging material along a first path, means disposed along said first path for forming trays in the packaging material for receiving a product, means for transporting a second sheet of packaging material along a second path including a path portion parallel to the first path, first sealing means for sealing the first and second sheets of material together around the periphery of each of said trays, said first sealing means leaving an unsealed portion in the periphery of each of said trays to form partially sealed packages, means for evacuating the partially sealed packages, means for injecting a selected gas into the partially sealed packages; second sealing means for sealing the unsealed portions of said packages to prevent escape of said selected gas, means disposed along said first path and downstream of said second sealing means for providing a pressure external of the sealed packages which is at a variance with the internal pressure of the packages, including detecting means operable to generate a leak detection signal upon detection of the selected gas, and indicating means disposed adjacent said first path and connected to said detecting means and operated by a leak detection signal to indicate defective packages.
Claim 6
Dependent Claim
59 words
The packaging apparatus according to claim 3, wherein said indicating means includes marking means disposed downstream of said detecting means, and said apparatus further comprises means connected between said detecting means and said marking means for delaying said leak detection signals for an interval to permit a defective package to move from said detecting means to said marking means.
Claim 7
Dependent Claim
42 words
The packaging apparatus according to claim 3, wherein said indicating means comprises marking means including an electromagnetic device which includes a movable member and a marking tip carried by said movable member, said electromagnetic device being operated by said leak detection signals.
Claim 8
Dependent Claim
37 words
The packaging apparatus according to claim 3, wherein said injecting means comprises a source of preservative gas, a source of tracer gas and blending means for mixing the preservative and tracer gases to form said selected gas.
Claim 9
Dependent Claim
14 words
The packaging apparatus according to claim 6, wherein said preservative gas includes carbon dioxide.
Claim 10
Dependent Claim
13 words
The packaging apparatus according to claim 6, wherein said tracer gas includes octafluorocyclobutane.
Claim 11
Dependent Claim
38 words
The packaging apparatus according to claim 3, wherein said means for providing an external pressure comprises means forming a chamber for receiving packages and means for establishing a pressure differential between the interior and exterior of a package.
Claim 12
Dependent Claim
21 words
The packaging apparatus according to claim 9, wherein said chamber forming means includes a movable member operable to squeeze a package.
Claim 13
Dependent Claim
30 words
The packaging apparatus according to claim 10, wherein said chamber-forming means includes a porous resilient pad carried by said movable member to contact a package and permit gas flow therethrough.
Claim 14
Dependent Claim
30 words
The packaging apparatus according to claim 9, wherein said means for providing an external pressure comprises a source of gas at a pressure connectable in fluid communication with said chamber.
Claim 15
Dependent Claim
14 words
The packaging apparatus according to claim 12, wherein said source is a vacuum source.
Claim 16
Dependent Claim
112 words
Apparatus for inspecting hermetically sealed packages which have internal atmosphere of a selected gas and which are joined together as a serial train of packages, said apparatus comprising means for moving said packages in line along a path. means forming a chamber for receiving said joined packages individually in sequence as they are moved along said path, means for pressuring said chamber while it contains a package to a pressure that is at a variance with the internal pressure of the package, means within said chamber for detecting the presence of the selected gas external of the packages, and means connected to and operated by said detecting means to mark leaky packages.
Claim 17
Dependent Claim
112 words
Apparatus for inspecting hermetically sealed packages which have internal atmosphere of a selected gas and which are joined together as a serial train of packages, said apparatus comprising means for moving said packages in line along a path. means forming a chamber for receiving said joined packages individually in sequence as they are moved along said path, means for pressuring said chamber while it contains a package to a pressure that is at a variance with the internal pressure of the package, means within said chamber for detecting the presence of the selected gas external of the packages, and means connected to and operated by said detecting means to mark leaky packages.
Claim 18
Dependent Claim
69 words
The apparatus according to claim 14, wherein said marking means is disposed downstream of said chamber and includes a marking chamber for receiving said joined packages in sequence and said apparatus further comprises delay means connected between said detecting means and said marking means for delaying operation of said marking means for an interval sufficient to permit a package to be moved from said chamber to said marking chamber.
Claim 19
Dependent Claim
85 words
The apparatus according to claim 14, wherein said means forming said chamber includes means forming a second chamber downstream of the first-mentioned chamber for receiving individual ones of said joined packages in sequence, said marking means includes a movable marking member within said second chamber, and further including delay means connected between said detecting means and said marking means for delaying operation of said marking means for a time sufficient to permit travel of a defective package from the first-mentioned chamber to said second chamber.
Claim 20
Dependent Claim
20 words
The apparatus according to claim 14, further comprising means disposed downstream from the marking means for separating said joined packages.
Claim 21
Dependent Claim
44 words
The apparatus according to claim 14, wherein said chamber forming means includes a cup-shaped member disposed above the path of travel of said joined packages, and means for moving said cup-shaped member into and out of sealing engagement with a package traversing said path.
Claim 22
Dependent Claim
32 words
The apparatus according to claim 18, wherein said cup-shaped member includes a passageway therein connecting its interior and exterior in fluid communication and means for connecting said passageway to a pressure supply.
Claim 23
Dependent Claim
18 words
The apparatus according to claim 18, wherein said means for moving said cup-shaped member includes an electromechanical actuator.
Claim 24
Dependent Claim
112 words
In a packaging machine of the type wherein serially connected train of packages are formed between sheets of sealable material as the sheets are stepped along a packaging line and the product is sealed in a preservative gas within each on the packaging line for testing the integrity of the gas-filled packages as the train of packages is stepped therethrough, said testing means including means for providing a pressure external of a package that is different from the internal pressure of a package, sensing means for detecting the presence of said preservative gas external of said package, and means for marking defective packages in response to the detection of said preservative gas.
Claim 25
Dependent Claim
112 words
In a packaging machine of the type wherein serially connected train of packages are formed between sheets of sealable material as the sheets are stepped along a packaging line and the product is sealed in a preservative gas within each on the packaging line for testing the integrity of the gas-filled packages as the train of packages is stepped therethrough, said testing means including means for providing a pressure external of a package that is different from the internal pressure of a package, sensing means for detecting the presence of said preservative gas external of said package, and means for marking defective packages in response to the detection of said preservative gas.
Claim 26
Dependent Claim
58 words
In a packaging machine according to claim 21, wherein said sensing means and said marking means are spaced apart on said line, and said testing means further includes delay means interposed between said sensing and said marking means to delay the operation of said marking means to accommodate package travel time between the spaced-apart sensing and marking means.
Claim 27
Dependent Claim
28 words
In a packaging machine according to claim 21, wherein said means for providing an external pressure to a package comprises means operable to contact and squeeze a package.
Claim 28
Dependent Claim
35 words
In a packaging machine according to claim 21, wherein said means for providing an external pressure to a package comprises a source of gas at a pressure for application to the exterior of a package.
Claim 29
Dependent Claim
17 words
In a packaging machine according to claim 24, wherein said source of gas included a vacuum source.
Claim 30
Independent Claim
157 words
A method of inspecting a plurality of sealed packages for leaks as the packages are moved along a line as a web of packages connected in longitudinal rows extending along the line and in rows transverse of the line comprising the steps of providing a selected atmosphere within each package of a transverse row as the transverse rows of packages reach a first location on the line, sealing the packages at the first location to prevent escape of the selected atmosphere, sensing for the presence of the selected atmosphere of each package of a transverse row in the environment of a pressure which is at a variance with the internal pressure of a package as the transverse rows of packages reach a second location on the line, and marking each defective package of a transverse row in response to detection of the selected atmosphere as the transverse rows of packages reach a third location on said line.
Claim 31
Independent Claim
157 words
A method of inspecting a plurality of sealed packages for leaks as the packages are moved along a line as a web of packages connected in longitudinal rows extending along the line and in rows transverse of the line comprising the steps of providing a selected atmosphere within each package of a transverse row as the transverse rows of packages reach a first location on the line, sealing the packages at the first location to prevent escape of the selected atmosphere, sensing for the presence of the selected atmosphere of each package of a transverse row in the environment of a pressure which is at a variance with the internal pressure of a package as the transverse rows of packages reach a second location on the line, and marking each defective package of a transverse row in response to detection of the selected atmosphere as the transverse rows of packages reach a third location on said line.
Claim 32
Dependent Claim
27 words
The inspection method set forth in claim 26, comprising the step of separating the web between transverse rows of packages prior to sensing for the selected atmosphere.
Claim 33
Dependent Claim
26 words
The inspection method set forth in claim 26, comprising the step of separating the web between the longitudinal rows prior to sensing for the selected atmosphere.
Claim 34
Dependent Claim
30 words
The inspection method set forth in claim 26, comprising the steps of separating the web between the longitudinal rows and the transverse rows prior to sensing for the selected atmosphere.
Claim 35
Dependent Claim
122 words
Apparatus for inspecting hermetically sealed serially connected packages which have an internal atmosphere of a selected gas, said apparatus comprising means for moving said serially connected packages in a line along a path, means forming a chamber for receiving said serially connected packages individually in sequence as they are moved along said path, means for vacuumizing said chamber while it contains a package to a pressure that is less than the internal pressure of the package, means within said chamber for detecting the presence of the selected gas external of the packages and generating a signal upon sensing of said selected gas, and means responsive to said signal operable to perform an operation on leaky packages to thereby indicate the leaky packages.
Claim 36
Dependent Claim
122 words
Apparatus for inspecting hermetically sealed serially connected packages which have an internal atmosphere of a selected gas, said apparatus comprising means for moving said serially connected packages in a line along a path, means forming a chamber for receiving said serially connected packages individually in sequence as they are moved along said path, means for vacuumizing said chamber while it contains a package to a pressure that is less than the internal pressure of the package, means within said chamber for detecting the presence of the selected gas external of the packages and generating a signal upon sensing of said selected gas, and means responsive to said signal operable to perform an operation on leaky packages to thereby indicate the leaky packages.
Claim 37
Independent Claim
182 words
A method of packaging a product between first and second sheets of packaging material comprising the steps of moving the first sheet of material along a path, forming trays in the first sheet as it traverses the path, depositing the product in the formed trays, moving the second sheet of material along a path parallel to the first sheet, sealing the first and second sheets together substantially but not fully around each formed tray to provide a series of packages, evacuating the partially sealed packages, inserting a selected atmosphere into the packages, sealing the partially sealed packages to prevent escape of the selected atmosphere, and sensing for the presence of said selected atmosphere in the environment of a pressure external of each of the sealed packages at a variance with their internal pressures as they reach a second position on the line, said step of sensing including generating a signal upon sensing of said selected atmosphere, and detecting said signal and indicating any leaker in response to detection of the signal as a defective package reaches a third position on the line.
Claim 38
Independent Claim
182 words
A method of packaging a product between first and second sheets of packaging material comprising the steps of moving the first sheet of material along a path, forming trays in the first sheet as it traverses the path, depositing the product in the formed trays, moving the second sheet of material along a path parallel to the first sheet, sealing the first and second sheets together substantially but not fully around each formed tray to provide a series of packages, evacuating the partially sealed packages, inserting a selected atmosphere into the packages, sealing the partially sealed packages to prevent escape of the selected atmosphere, and sensing for the presence of said selected atmosphere in the environment of a pressure external of each of the sealed packages at a variance with their internal pressures as they reach a second position on the line, said step of sensing including generating a signal upon sensing of said selected atmosphere, and detecting said signal and indicating any leaker in response to detection of the signal as a defective package reaches a third position on the line.
Claim 39
Dependent Claim
33 words
The method according to claim 31, wherein the step of indicating includes the step of marking defective packages at a point downstream from and at a later time than the step of sensing.
Claim 40
Dependent Claim
43 words
The method according to claim 31, wherein the step of subjecting each package to an external pressure at a variance with its internal pressure is further defined as applying a mechanical force to the exterior of each package to mechanically squeeze each package.
Claim 41
Dependent Claim
38 words
The method according to claim 31, wherein the step of subjecting each package to an external pressure at a variance with its internal pressure is further defined as applying a gas pressure to the exterior of each package.
Claim 42
Dependent Claim
37 words
The method according to claim 31, wherein the step of subjecting each package to an external pressure at a variance with its internal pressure is further defined as applying a vacuum to the exterior of each package.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-07-12 | 1975-01-11 | 1975-07-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-12 | 1979-01-11 | 1979-07-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-12 | 1983-01-11 | 1983-07-13 | $7700.00 | Window Closed / Lapsed |