Sealing method for packaging container, heat-treating plates for use in the sealing method and inspection method for sealed portion of packaging container

• US 20010015056A1
• Filed: 02/15/2001
• Published: 08/23/2001
• Est. Priority Date: 02/23/2000
• Status: Active Grant

• Current Assignee: Toyo Jidoki Company Limited (Nabtesco Corporation)
• Original Assignee: Toyo Jidoki Company Limited (Nabtesco Corporation)
• Inventors: Fujitomi, Takehiro, Hirata, Keizou, Masuoka, Yasuhiro, Hiramoto, Shinichi
• Granted Patent: US 6,655,114 B2
• Time in Patent Office: Days
• US Class Current: 53/479
• CPC Class Codes: B29C 65/18 using heated tools
• CPC Class Codes: B29C 65/305 involving the use of cartridge heaters
• CPC Class Codes: B29C 65/7847 using vacuum to hold at least one of the parts to be joined vacuum work holders in general B25B11/005
• CPC Class Codes: B29C 65/7882 said parts to be joined moving in a circular path
• CPC Class Codes: B29C 65/7885 Rotary turret joining machines, i.e. having several joining tools moving around an axis
• CPC Class Codes: B29C 65/8253 by the use of waves or particle radiation, e.g. visual examination, scanning electron microscopy, or X-rays B29C65/8292 takes precedence
• CPC Class Codes: B29C 66/0342 Cooling, e.g. transporting through welding and cooling zone
• CPC Class Codes: B29C 66/1122 Single lap to lap joints, i.e. overlap joints B29C66/45, B29C66/472, B29C66/52272 take precedence
• CPC Class Codes: B29C 66/30223 said melt initiators being rib-like
• CPC Class Codes: B29C 66/342 Preventing air-inclusions
• CPC Class Codes: B29C 66/345 Progressively making the joint, e.g. starting from the middle B29C66/8341, B29C65/12, B29C65/14, B29C65/16 take precedence
• CPC Class Codes: B29C 66/53263 said spouts comprising wings, e.g. said spouts being of ship-like or canoe-like form to avoid leaks in the corners
• CPC Class Codes: B29C 66/723 being multi-layered B29C66/7292, B29C66/72941 take precedence
• CPC Class Codes: B29C 66/81423 being concave
• CPC Class Codes: B29C 66/81431 comprising a single cavity, e.g. a groove
• CPC Class Codes: B29C 66/8181 characterised by the cooling constructional aspects
• CPC Class Codes: B29C 66/81821 of the welding jaws
• CPC Class Codes: B29C 66/8221 Scissor or lever mechanisms, i.e. involving a pivot point
• CPC Class Codes: B29C 66/82263 Follower pin or roller cooperating with a groove
• CPC Class Codes: B29C 66/8242 Pneumatic or hydraulic drives using fluid pressure directly acting on the parts to be joined B29C66/8266
• CPC Class Codes: B29C 66/8324 : Joining or pressing tools pivoting around one axis scissor or lever transmission mechanisms B29C66/8221; tools self-aligning to the joining plane B29C66/8163
• CPC Class Codes: B29C 66/849 : Packaging machines
• CPC Class Codes: B29C 66/8511 : Bag making machines
• CPC Class Codes: B29C 66/91445 : by steps
• CPC Class Codes: B29C 66/9672 : involving special data inputs, e.g. involving barcodes, RFID tags
• CPC Class Codes: B29C 66/974 : by checking the bead or burr form
• CPC Class Codes: B29L 2031/7148 : Blood bags, medical bags
• CPC Class Codes: B65B 43/44 : from supply magazines
• CPC Class Codes: B65B 43/50 : using rotary tables or turrets B65B43/46 takes precedence
• CPC Class Codes: B65B 51/32 : Cooling, or cooling and pressing, package closures after heat-sealing
• CPC Class Codes: B65B 61/186 : by applying or incorporating rigid fittings, e.g. discharge spouts

Abstract

A method of sealing an opening portion of a packaging container by utilizing fusion bonding of the base material, together with an apparatus and method for inspecting the sealed portion. The container material has a welding layer as the innermost layer. The welding layer is melted at a seal portion defined along the edge of the opening portion of the container. A part of the melt from the welding layer is allowed to flow out from the edge of the opening portion, thereby sealing the seal portion and also forming an efflux layer outside the opening portion by the melt flowing out and solidified. An image of at least a part of the sealed portion and its vicinities is taken. At least a part of the image is defined as an inspection region. The image of the inspection region is subjected to predetermined image processing to calculate data concerning the efflux layer formed outside the sealed portion. The calculated data is compared with a preset condition for judgment to judge the sealing quality of the sealed portion.

Claims

1. A method of sealing an opening portion of a packaging container formed by using a base material formed from a stack of a plurality of layers in which at least an innermost layer is a welding layer made of a thermoweldable material, said method comprising the steps of:

melting said welding layer at a seal portion defined along an edge of said opening portion of said packaging container; and

allowing a part of a melt from said welding layer to flow out from the edge of said opening portion at a predetermined position along said edge, thereby sealing said seal portion and also forming an efflux layer outside said opening portion by said melt flowing out and solidified.

2. A method according to

claim 1

, wherein said seal portion is welded at a welding portion separated from the edge of said opening portion by a non-welding portion with a predetermined width extending along said edge, and at said predetermined position along said edge, an extension extending from said welding portion to said edge across said non-welding portion is also welded.

3. A method according to

claim 2

, said method comprising:

a heating step of melting said seal portion by pressing it between a pair of heating plates under application of heat; and

a cooling step of cooling said seal portion by pressing it between a pair of cooling plates;

wherein said step of allowing a part of said melt to flow out from said opening portion is carried out during said cooling step.

4. A method according to

claim 3

, wherein said heating step includes a first heating step and a second heating step, wherein at said second heating step, said seal portion is melted under application of heat in such a manner as to leave a non-welding portion narrower in width than a non-welding portion left at said first heating step.

5. A method according to

claim 4

, wherein said non-welding portion left at said first heating step has a width of approximately 1.5 millimeters, and said non-welding portion left at said second heating step has a width of approximately 1 millimeter, and wherein at said cooling step, at least a welding portion melted at said second heating step and said extension are cooled under application of pressure.

6. A method according to

claim 1

, said method comprising:

a heating step of melting said seal portion by pressing it between a pair of heating plates under application of heat; and

a cooling step of cooling said seal portion by pressing it between a pair of cooling plates;

wherein said step of allowing a part of said melt to flow out from said opening portion is carried out during said cooling step.

7. A method according to

claim 6

, wherein said heating step includes a first heating step and a second heating step, wherein at said second heating step, said seal portion is melted under application of heat in such a manner as to leave a non-welding portion narrower in width than a non-welding portion left at said first heating step.

8. A method according to

claim 7

;

wherein said non-welding portion left at said first heating step has a width of approximately 1.5 millimeters, and said non-welding portion left at said second heating step has a width of approximately 1 millimeter, and wherein at said cooling step, at least a welding portion melted at said second heating step and an extension extending from a welding portion of the seal portion across the non-welding portion to the edge are cooled under application of pressure.

9. A pair of heat-treating plates for sealing an opening portion of a packaging container by holding said opening portion from both sides, said packaging container being formed by using a base material formed from a stack of a plurality of layers in which at least an innermost layer is a welding layer made of a thermoweldable material, said heat-treating plates comprising:

respective welding portion-pressing portions facing each other to press a welding portion of said packaging container defined at a predetermined distance from an edge of said opening portion; and

respective extension-pressing portions facing each other to press an extension defined at a predetermined position along said edge of said opening portion to extend with a predetermined width from said welding portion to said edge.

10. A pair of heat-treating plates according to

claim 9

, wherein sealing of said opening portion of said packaging container is carried out by melting said welding portion by application of heat with heating plates and then cooling said welding portion with cooling plates, wherein said heat-treating plates are said cooling plates.

11. An apparatus for inspecting a sealed portion of a packaging container, said sealed portion being sealed by utilizing fusion bonding of a material constituting the packaging container, said apparatus comprising:

an imaging device having a field of view capable of taking an image of an imaging subject including at least a part of said sealed portion and its vicinities; and

a controller;

said controller including;

a defective range setting unit for setting inspection conditions and a criterion for judgment of sealing quality of said sealed portion;

a sealing quality judging unit; and

a central control unit;

wherein said central control unit controls said apparatus, captures the image taken with said imaging device, defines an inspection region including at least a part of said image in accordance with said inspection conditions, divides said inspection region into a plurality of pixels of a predetermined size, and judges whether or not each pixel located outside said sealed portion is filled with an efflux layer formed by a melt of said material flowing out of said sealed portion, and said sealing quality judging unit compares a result of judgment made by said central control unit with said criterion for judgment to judge sealing quality of said sealed portion.

12. An apparatus according to

claim 11

, wherein said defective range setting unit sets a reference value concerning the number of pixels filled with said efflux layer as a criterion for judgment of sealing quality, and said central control unit calculates the number of pixels filled with said efflux layer among pixels located outside said sealed portion.

13. An apparatus according to

claim 12

, wherein said defective range setting unit further sets a reference value for a maximum height of said efflux layer from an end edge of said sealed portion as a criterion for judgment of sealing quality, and said central control unit measures the maximum height of said efflux layer from the end edge of said sealed portion.

14. An apparatus according to

claim 13

, wherein said controller further includes an inspection position control unit for detecting a position of an inspection reference part defined by a predetermined part of said imaging subject within said field of view of said imaging device and for controlling the position of said inspection region according to the position of said inspection reference part.

15. An apparatus according to

claim 14

, wherein said packaging container is a spouted packaging container having a packaging container body and a spout welded to an opening portion of said packaging container body, and said imaging subject includes a welding portion where said spout and said packaging container body are welded to each other, said inspection region being set so as to include an efflux layer formed by a melt of said material flowing out of said packaging container body and solidified at the welding portion of said spout welded to said packaging container body.

16. An apparatus according to

claim 11

, wherein said controller further includes an inspection position control unit for detecting a position of an inspection reference part defined by a predetermined part of said imaging subject within said field of view of said imaging device and for controlling the position of said inspection region according to the position of said inspection reference part.

17. An apparatus according to

claim 16

, wherein said packaging container is a spouted packaging container having a packaging container body and a spout welded to an opening portion of said packaging container body, and said imaging subject includes a welding portion where said spout and said packaging container body are welded to each other, said inspection region being set so as to include an efflux layer formed by a melt of said material flowing out of said packaging container body and solidified at the welding portion of said spout welded to said packaging container body.

18. An apparatus according to

claim 11

, wherein said packaging container is a spouted packaging container having a packaging container body and a spout welded to an opening portion of said packaging container body, and said imaging subject includes a welding portion where said spout and said packaging container body are welded to each other, said inspection region being set so as to include an efflux layer formed by a melt of said material flowing out of said packaging container body and solidified at the welding portion of said spout welded to said packaging container body.

19. An automatic food and/or drink filling and packaging system comprising an apparatus for inspecting a sealed portion of a packaging container, said sealed portion being sealed by utilizing fusion bonding of a material constituting the packaging container, said apparatus comprising:

an imaging device having a field of view capable of taking an image of an imaging subject including at least a part of said sealed portion and its vicinities; and

a controller;

said controller including;

a defective range setting unit for setting inspection conditions and a criterion for judgment of sealing quality of said sealed portion;

a sealing quality judging unit; and

a central control unit;

wherein said central control unit controls said apparatus, captures the image taken with said imaging device, defines an inspection region including at least a part of said image in accordance with said inspection conditions, divides said inspection region into a plurality of pixels of a predetermined size, and judges whether or not each pixel located outside said sealed portion is filled with an efflux layer formed by a melt of said material flowing out of said sealed portion, and said sealing quality judging unit compares a result of judgment made by said central control unit with said criterion for judgment to judge sealing quality of said sealed portion.

20. A method of inspecting a sealed portion of a packaging container, said sealed portion being sealed by utilizing fusion bonding of a material constituting the packaging container, said method comprising the steps of:

taking an image of an imaging subject including at least a part of said sealed portion and its vicinities;

defining at least a part of said image as an inspection region;

subjecting an image of said inspection region to predetermined image processing to calculate data concerning an efflux layer formed outside said sealed portion by a melt of said material flowing out of said sealed portion; and

comparing said data with a preset condition for judgment to judge sealing quality of said sealed portion.

21. A method according to

claim 20

, wherein said data is obtained by dividing the image of said inspection region into pixels of a predetermined size and judging whether or not each of the pixels is filled with said efflux layer.

22. A method according to

claim 21

, further comprising the steps of:

setting reference information concerning an inspection reference part defined by a predetermined part of said imaging subject within a field of view of an imaging device for taking an image of said imaging subject;

storing said reference information;

detecting said inspection reference part from the image taken with said imaging device;

performing a comparison operation to compare information concerning said detected inspection reference part with said reference information; and

controlling the position of said inspection region according to a result of said comparison operation.

23. A method according to

claim 20

, further comprising the steps of:

setting reference information concerning an inspection reference part defined by a predetermined part of said imaging subject within a field of view of an imaging device for taking an image of said imaging subject;

storing said reference information;

detecting said inspection reference part from the image taken with said imaging device;

performing a comparison operation to compare information concerning said detected inspection reference part with said reference information; and

controlling the position of said inspection region according to a result of said comparison operation.