Method and apparatus for packaging

Claim 3

A method of forming a package according to claim 1, wherein said two layers of film are made of thermoplastic material, and heat is applied at said transversely extending areas to sever both layers of film on a transverse line of cut and to form seals between said two layers of film one in advance of and the other to the rear of said line of cut.

Claim 4

A method of forming a package according to claim 2, wherein said two layers of film are superimposed one upon the other as said layers are being fed and sealed, and whereby when said seals are formed, said two layers are stretched lengthwise between said seals to form a substantially flat envelope.

Claim 5

The method defined in claim 1 wherein said tubes are continually formed and disposed in separate succession longitudinally forwardly of the leading end of the juxtaposed layers and articles are advanced in synchronous succession toward a loading station wherein each article is inserted iNto a tube by relative movement between the tube and article.

Claim 6

The method defined in claim 4, including the step of positively separably displacing each formed tube at said leading end rapidly forwardly prior to insertion of the article.

Claim 7

The method defined in claim 1 wherein both the article and the tube are moved endwise towards each other during insertion of the article.

Claim 8

The method defined in claim 1, including the step of withdrawing said inserted device following at least partial insertion of said article into said tube.

Claim 9

The method of forming a package according to claim 1, wherein said article and tube are advanced in side-by-side paths and said article and tube are automatically moved laterally relatively to each to contain the article within the tube during said advance.

Claim 10

A method of forming a package as claimed in claim 8, which includes the further step of subjecting the tube containing the article to a heat shrinking operation.

Claim 11

Apparatus for forming a package containing an article comprising means for feeding a web comprising two layers of wrapping film in close juxtaposition along aligned paths of travel in the same direction, tube opening means mounted for movement in said direction of travel and actuatable between a first non-expanded condition wherein it may be inserted between said film layers and a second expanded condition, means for inserting said tube opening means while in non-expanded condition between said two layers of film, means for causing a sealed relationship between said two layers of film at transversely extending separate areas located at opposite sides of the inserted tube opening means and spaced apart relative to said direction of travel to form a compartment for said inserted device, means for severing the web at said areas to separate individual compartments from the web, means for actuating said inserted tube opening means to expanded condition for opening out the associated severed compartment to form a separated tube having at least one open end, said opening means including means for frictionally gripping the interior of said tube to support and convey said tube in said direction of travel, and means for introducing an article to be wrapped into the open end of said tube.

Claim 12

Apparatus for forming a package containing an article comprising means for feeding a web comprising two layers of wrapping film in close juxtaposition along aligned paths of travel in the same direction, tube opening means mounted for movement in said direction of travel and actuatable between a first non-expanded condition wherein it may be inserted between said film layers and a second expanded condition, means for inserting said tube opening means while in non-expanded condition between said two layers of film, means for causing a sealed relationship between said two layers of film at transversely extending separate areas located at opposite sides of the inserted tube opening means and spaced apart relative to said direction of travel to form a compartment for said inserted device, means for severing the web at said areas to separate individual compartments from the web, means for actuating said inserted tube opening means to expanded condition for opening out the associated severed compartment to form a separated tube having at least one open end, said opening means including means for frictionally gripping the interior of said tube to support and convey said tube in said direction of travel, and means for introducing an article to be wrapped into the open end of said tube.

Claim 13

Apparatus as defined in claim 10 wherein said film layers are continuous webs of material, means is provided for forming and separating said tubes in succession automatically at the leading end of the web of juxtaposed films, and means is provided for advancing articles in synchronous succession with said tubes toward a loading station wherein means is provided for inserting each article into a tube by relative displacement therebetween.

Claim 14

Apparatus as claimed in claim 11, in which the means for producing relative transverse displacement between the tube and an article to be wrapped, to introduce the article into the tube, comprises means for displacing the article and the tube toward each other.

Claim 15

Apparatus as claimed in claim 10, which also includes a product conveyor means adapted to feed an article to be wrapped in the same sense as the web is fed.

Claim 16

Apparatus as claimed in claim 13, in which the product feed conveyor is provided with a plurality of product carriers each of which is mounted for lateral movement towards and away from the path of movement of the web.

Claim 17

Apparatus as claimed in claim 13, in which the tube opening means is carried by the product conveyor means.

Claim 18

Apparatus as claimed in claim 15, in which the tube opening means is connected to be operated by the movement of that device produced by the product conveyor means.

Claim 19

Apparatus as claimed in claim 16, including stationary cam means and in which the tube opening means is provided with an operating mechanism including a part engageable with said stationary cam means during feeding of the tube opening means on the product conveyor.

Claim 20

Apparatus as claimed in claim 17, in which the tube opening means includes tube eNgaging members that initially lie in a collapsed condition in a substantially flat plane between the paths of the two film layers, the said tube engaging members being articulated so that, when activated, they move from the collapsed condition to an erect condition.

Claim 21

Apparatus as claimed in claim 18, in which the tube engaging members are mounted to turn about respective pivots from the collapsed to the erect condition, the operating mechanism being adapted to convert a rectilinear motion of a cam engaging part into turning motion of the tube engaging members.

Claim 22

Apparatus as claimed in claim 14, in which a pusher is mounted to move laterally on each carrier to push an article to be wrapped from the carrier into a film tube, and activating mechanism for the pusher is provided which operates the pusher in response to travel of the carrier on the product conveyor.

Claim 23

Apparatus as claimed in claim 10, in which said means for causing said sealed relationship includes a sealer head carried by a mechanism constructed and arranged to reciprocate the head parallel with the path of feed of the film, and to move the sealer head towards and away from the film to effect the sealing operations in timed relationship to the speed of travel of the film.

Claim 24

Apparatus as claimed in claim 21, in which the sealer head mechanism includes an oscillating motion transmitter of variable stroke length, but with a period directly related to the speed of film feed.

Claim 25

Apparatus as claimed in claim 22, in which the motion transmitter comprises a lever which turns on a fulcrum which is adjustable to vary the effective length of at least one arm of the lever.

Claim 26

Apparatus as claimed in claim 21, including a film feed conveyor to carry the film through the zone of operation of the sealer head and the sealer head being supported by a reciprocable carriage having rollers adapted to engage on the film and to hold the film on to the film feed conveyor.

Claim 27

Apparatus as claimed in claim 24, in which means is provided whereby at least one roller of the sealer head is given a sudden rotation at the end of the movement of the carriage in the same direction as the film, for the purpose of pulling a formed tube of film away from the following bulk of film.

Claim 28

Apparatus as claimed in claim 21, including a cam driven in synchronism with the film feed and operably connected to periodically depress the sealer head against a resilient loading to periodically move the head into engagement with the film.

Claim 29

Apparatus as claimed in claim 10, in which there is a heat shrink tunnel and conveyor means for carrying the wrapped article into the tunnel.

Claim 30

Apparatus as defined in claim 10 wherein said means for causing said sealed relationship between the films comprises a support over which said films are moved in superposed relation, a transversely extending heat sealing and film severing head mounted above said support for reciprocation in the path of film movement, and means for cyclically moving said head down onto the moving film on said support, moving said head a predetermined distance along said support in contact with the film, separating the head from said film and returning the head back along the support to initial position.

Claim 31

Apparatus as defined in claim 28, wherein said head is mounted on a reciprocable carriage and cam means is provided for reciprocating said carriage along said support, and resilient means is provided between said head and carriage whereby said head is biased to separate from said film, and cam means driven is synchronism with the cam means for reciprocating the carriage is operably connected to said head to displace the head into engagement with the film during displacement of said carriage in said film feed direction.

Claim 32

Apparatus as defined in claim 28, wherein said support is the upper flight of an endless conveyor driven in the direction of film feed, said head is supported on a reciprocable carriage having rollers in contact with the film On the support, and means is provided for synchronizing the speed of said conveyor flight with the speed of said carriage in the film feed direction.

Claim 33

Apparatus as defined in claim 30, wherein means is provided for positively rotating said rollers during return reciprocation of said carriage whereby to substantially eliminate slipping between the film and rollers.

Claim 34

Apparatus as defined in claim 30, wherein said support conveyor comprises a resiliently backed endless belt.

Claim 35

Apparatus as defined in claim 10 wherein said tube gripping means is disposed to grip said tube adjacent the open end of the tube and support means is provided underlying the opposite end of the separated tube as it is conveyed by said tube opening means.