Method and machine for filled bag production

Claim 2

In a method for making and filling bags, the steps of manufacturing a series of bags from a strip of sheet material while conveying the thus-manufactured bags with a first conveyer during a first conveying operation at least during the last stage of manufacture of the bags in a stepwise manner according to which predetermined advance and dwell intervals alternate with each other, conveying the thus-manufactured bags with a second conveyer during a second conveying operation to a filling station, with the conveying of the bags to the filling station also being carried out in a stepwise manner according to which predetermined advance and dwell intervals alternate with each other, delivering a plurality of the manufactured bags to said second conveyer at each dwell interval of said second conveying operation while providing for a dwell and advance interval during said second conveying operation a total time which is a multiple of the total time provided for a dwell and advance interval during said first conveying operation, and simultaneously filling each plurality of bags delivered to said second conveyer during a dwell interval of said second conveying operation, so that each bag may be filled during an interval substantially longer than the dwell interval of the first conveying operation to gain additional filling time without retarding the rate of manufacture of the bags.

Claim 3

In a method as recited in claim 1 and including the steps of conveying the filled bags with a third conveyer during a third conveying operation to a bag-closing station with said third conveying operation also having predetermined advance and dwell intervals which alternate with each other, delivering to the third conveyer during each dwell interval of said third conveying operation a number of filled bags which is a multiple of the plurality of manufactured bags delivered to the second conveyer at each dwell interval of the second conveying operation, and simultaneously closing at the bag-closing station said number of filled bags which is a multiple of said plurality of manufactured bags, so that the rate of operation of the third conveyer may be reduced as compared to the rate of operation of the second conveyer.

Claim 4

In a method as recited in claim 1 and wherein said last stage of manufacture of the bags includes the step of conveying the latter in said stepwise manner with the bags all having free ends projecting beyond the first conveyer, and said last stage of manufacture including the step of simultaneously sealing said free ends of a plurality of the bags which extend along a given row during each dwell interval of said first conveying operation with each bag requiring a time equal to a number of said dwell and advance intervals of said first conveying operation to move beyond a sealing structure which seals said free ends of said bags in said row, whereby each bag is subjected at said free end thereof to a plurality of sealing operations during said first conveying operation.

Claim 5

In a method as recited in claim 1 and wherein the strip of sheet material is first formed into a flat tube, and including the step of directing said flat tube downwardly toward said first conveyer while cutting across the flat tube which extends downwardly to form individual lengths therefrom, and freeing the cut lengths to fall by gravity to said first conveyer while the cut lengths remain in the vertical attitude which the flat tube has just prior to cutting thereof into said lengths.

Claim 6

In a method as recited in claim 4 and including the step of supporting the filled bags on a slide surface along which the bags are advanced while being delivered to the third conveyer, with the bags being delivered to a location situated over said third conveyer, and removing a part of the slide surface from beneath the bags when they arrive at a location over the third conveyer so that the bags fall by gravity to the third conveyer to compact material in the bags while they fall to the third conveyer.

Claim 7

In an apparatus for manufacturing and filling bags, manufacturing means for manufacturing a plurality of bags from a strip of sheet material, said manufacturing means including a first conveyer means for conveying the bags at least during the last stage of the manufacture thereof in a stepwise manner having predetermined dwell and advance intervals, filling means for filling a plurality of the thus-manufactured bags simultaneously while said plurality of bags remain stationary, second conveyer means for conveying the manufactured bags to said filling means in groups each of which is made up of said plurality of bags which are simultaneously filled by said filling means, with said second conveyer means having predetermined dwell and advance intervals according to which successive groups of bags are filled during each dwell interval of said second conveyer means, and delivering means for delivering a plurality of manufactured bags equal to the number of bags filled by said filling means at each dwell interval of said second conveyer means to said second conveyer means from said first conveyer means during each dwell interval of said second conveyer means while said first conveyer means carries out a number of dwell and advance cycles equal to the plurality of bags filled simultaneously by said filling means, whereby relatively long dwell intervals for filling the bags are gained without reducing the rate of manufacture of the bags.

Claim 8

In an apparatus for manufacturing and filling bags, manufacturing means for manufacturing a plurality of bags from a strip of sheet material, said manufacturing means including a first conveyer means for conveying the bags at least during the last stage of the manufacture thereof in a stepwise manner having predetermined dwell and advance intervals, filling means for filling a plurality of the thus-manufactured bags simultaneously while said plurality of bags remain stationary, second conveyer means for conveying the manufactured bags to said filling means in groups each of which is made up of said plurality of bags which are simultaneously filled by said filling means, with said second conveyer means having predetermined dwell and advance intervals according to which successive groups of bags are filled during each dwell interval of said second conveyer means, and delivering means for delivering a plurality of manufactured bags equal to the number of bags filled by said filling means at each dwell interval of said second conveyer means to said second conveyer means from said first conveyer means during each dwell interval of said second conveyer means while said first conveyer means carries out a number of dwell and advance cycles equal to the plurality of bags filled simultaneously by said filling means, whereby relatively long dwell intervals for filling the bags are gained without reducing the rate of manufacture of the bags.

Claim 9

The combination of claim 6 including a bag-closing means for simultaneously closing a number of filled bags which is a multiple of the plurality of bags forming each group sImultaneously filled by said filling means, third conveyer means for conveying the filled bags to said bag-closing means in a stepwise manner having predetermined dwell and advance intervals, and transfer means cooperating with said second and third conveyer means for transferring said number of filled bags from said second to said third conveyer means during each dwell interval of the latter, whereby the dwell intervals of said third conveyer means are longer than the dwell intervals of said second conveyer means so that the speed of operation of said third conveyer means is less than the speed of operation of said second conveyer means.

Claim 10

The combination of claim 6 and wherein said first conveyer means conveys the bags in said stepwise manner during said last stage of manufacture thereof in a manner according to which said first conveyer means holds the bags while leaving free end portions thereof exposed beyond said first conveyer means with said free ends arranged in a row, and sealing means situated in the path of movement of said row of free ends for simultaneously sealing the latter while said first conveyer means conveys each bag through a number of dwell and advance cycles before each bag moves beyond said sealing means so that each bag is sealed at its free end by a number of sealing operations provided by said sealing means.

Claim 11

The combination of claim 6 and wherein said bag manufacturing means first provides a flat elongated tube of sheet material from the strip of sheet material and delivers the flat tube of sheet material to a location from which the flat tube of sheet material hangs down toward a receiving portion of said first conveying means, said manufacturing means including a cutting means for cutting across the hanging portion of the tube of sheet material to provide therefrom predetermined lengths which successively fall to said receiving portion of said first conveyer means.

Claim 12

The combination of claim 6 and wherein said second conveyer means has the construction of a rotary turret of polygonal configuration having a number of substantially straight sides at each of which said delivering means delivers said group of bags from said first to said second conveyer means, and opening means carried by said turret at each of said sides thereof for opening the plurality of bags at each side of said turret at a top part of said bag before the plurality of bags reach said filling means.

Claim 13

The combination of claim 10 and wherein said bag-opening means includes a parallelogram linkage having a holding means for holding one wall of the bag against a side of the turret and a movable bag-opening element for displacing an opposite wall of each bag away from said one wall thereof, and cam means cooperating with said parallelogram linkage for operating the latter to open the bags while they are held against the turret by the holding means.

Claim 14

The combination of claim 7 and wherein said transfer means includes a wall engaging the bottom ends of the filled bags and along which the filled bags slide while they are transferred by said transfer means from said second to said third conveyer means, said wall being situated over a receiving portion of said third conveyer means and having over said receiving portion of said third conveyer means a removable portion of said wall, and removing means operatively connected to said removable portion of said wall for displacing said removable portion from beneath bags over said receiving portion of said third conveyer means so that the bags then fall to said third conveyer means to have material in the bags compacted while the bags are received by said third conveyer means.