US3759508A

US3759508A - Apparatus and method for feeding blanks

Info

Publication number: US3759508A
Application number: US00205212A
Authority: US
Inventors: S Jeppsson
Original assignee: Individual
Current assignee: Individual
Priority date: 1970-12-14
Filing date: 1971-12-06
Publication date: 1973-09-18
Anticipated expiration: 1990-09-18
Also published as: GB1376619A; SE346499B; DE2159710A1

Abstract

The lateral edges of a continuous web of paper are folded into superimposed relationship and glued together to form a continuous tube. The tube is cut into sack blanks which are fed by a first conveyor belt to a delivery station comprising a pair of nip rolls and a platen mounted to reciprocate transversely relative to the first conveyor belt. The platen has an opening formed therethrough for permitting each sack blank to fall onto a second conveyor for subsequent formation of an end closure on each sack blank.

Description

United States Patent [191 [111 3,759,508 Jepp sson Sept, W, W73

54] APPARATUS Ann Mari-ion iron riannrna 2,665,633 1/1954 Schubert 271/010. 4

BLANKS 2,612,982 l0/l952 Michaux l98/24 Inventor: Sven Torsten .Ieppsson,

Drottninggatan 49, Orebro, Sweden Filed: Dec. 6, 1971 Appl. No.: 205,212

Foreign Application Priority Data Dec. 14, 1970 Sweden l69ll/7O U.S. CI. 271/69 Int. CI lllllfifilm ZWtW Field of Search 271/63 R, 69, DIG. 4,

References Cited UNITED STATES PATENTS l2/l94l Carlson 27l/DIG. 4

Primary Examiner-Edward A. Srolta Att0rney-Paul S Lempio [57] ABSTRACT The lateral edges of a continuous web of paper are folded into superimposed relationship and glued together to form a continuous tube. The tube is cut into sack blanks which are fed by a first conveyor belt to a delivery station comprising a pair of nip rolls and a platen mounted to reciprocate transversely relative to the first conveyor belt. The platen has an opening formed therethrough for permitting each each blank to fall onto a second conveyor for subsequent formation of an end closure on each sack blank.

18 Claims, 3 Drawing Figures PATENTED SE?! 8 I973 SHEET 2 OF 3 PATENTEU SE?! a ma SHEET 3 or 3 APPARATUS AND METHOD FUR l llBlElD'liltlG BLANKS BACKGROUND OF THE INVENTION The invention relates to an apparatus and method for forming tubular receptacles, such as paper sacks.

Paper sacks are normally conveyed through a tube forming station wherein a continuous web of paper is folded longitudinally and glued together at superimposed edges thereof to form a continuous tube. The tube is then cut into suitable lengths to form individual sack blanks. The blanks are moved through an end closure forming station wherein a strip of paper is folded and glued over an open end of each sack blank, after which the formed end closure is reinforced with a sewn seam. Alternatively, the bottom closure can be sewn prior to the gluing of a strip of reinforcement paper thereover.

The conveyance of the sack blanks from the tube forming station to the end closure forming station requires a 90 change in the direction of feed for the sack blanks. Such an abrupt change gives rise to numerous feeding problems which, to date, have normally been solved by the manual transfer of stacked sack blanks to the latter station. The primary reason for utilizing such manual feeding methods has been the difficulty of perfecting a feeding device and method for reliably gripping and feeding only one sack at a time, while yet maintaining high manufacturing speeds.

Attempts to engage an edge of an individual sack blank for feeding purposes have oftentimes failed since the tendency is to inadvertently engage and sew several blanks together simultaneously. This problem is espe cially apparent with respect to expandable sack blanks which are folded inwardly along their side edges. Another possible solution to the problem is to employ suction cups or the like to grip a sack blank from above and lift it off its stack. However, this solution has also proved impracticable since the tubular sack blank has a tendency to open, thus preventing its precise feed to the end closure forming station.

SUMMARY OF THE INVENTEON An object of the present invention is to overcome the above, briefly described problems by providing an apparatus and method for economically and efficiently feeding blanks, such as paper sack blanks. Such apparatus is particularly useful in sack or bag forming machines wherein a continuous web is formed into a tube, cut into separate blanks and an open end of each blank is thereafter closed. The apparatus of this invention essentially comprises a delivery station having a platen reciprocally mounted therein to receive blanks from a first conveyor in one direction and for precisely and expeditiously placing each blank onto a second conveyor to move the blank in a second, transverse direction.

BRIEF DESCRllPTlON OF THE DRAWHNGS Other objects of this invention will become apparent from the following description and accompanying drawings wherein:

FIG. 1 is a top plan view schematically illustrating a paper sack forming machine embodying this invention;

FIG. 2 is a perspective view of a delivery station employed in such machine; and

FIG. 3 is a perspective view of a reciprocal platen employed in the delivery station.

DETAILED DESCRIPTION FIG. 1 schematically illustrates a tube forming means or station l and an end closure forming means or station 2, adapted for the manufacture of paper sacks or the like. The paper sacks are formed by longitudinally folding and gluing together one or more plies of paper originating at rolls 3. After the continuous web of paper has been folded and glued together to form a continuous tube, the tube is cut into separated, tubular sack blanks.

The sack blanks, or any other types of deliverable articles, are fed from the tube forming station to a delivery means or station 6 by a first endless conveyor means or belt 4 which moves in a first linear direction theretoward. The delivery station delivers the sack blanks to a second endless conveyor means or belt 7, positioned vertically below belt 41 to move in a second direction preferably perpendicular to the first direction, which carries the blanks to the end closure forming station.

The latter station comprises a conventional combined sewing and gluing machine wherein a strip of paper is folded and glued over one open end of each sack blank. The formed end closure may be reinforced by means of a sewn seam, formed along the attached strip of paper. The completed sacks are then fed out onto an intermittently operating third conveyor belt 8 on which the sacks are laid in stacks 9.

Delivery station 6 is clearly shown in FIG. 2. When the sack blanks arrive at the delivery station, along the first linear path on conveyor belt 4, each blank is moved between two feed or nip roll means lid. The rolls rotate at a sufficiently high speed to discharge and impel each sack blank so that the leading end thereof fully reaches the rearward end of the delivery station. F ragments'of a vertically disposed and horizontally adjustable baffle plate 16b are shown. in lFlG. 2. Such baffle plate may be adjusted to accommodate blanks of various widths to precisely guide and locate each blank over the platen.

Upon entry into the delivery station, the sack blank is urged downwardly by overlying guide means or rails il7, converging downwardly toward a platen ill from rolls l0, and thereafter falls by gravity onto the platen. As the stationary guide-rails force the tubular sack blank downwardly, they simultaneously prevent the blank from opening under the influence of the encountered air resistance. This function is very advantageous since it allows the delivery station to operate at high delivery speeds. i

An extensible and retractable fluid actuator, such as a double-acting hydraulic cylinder having it housing secured to a stationary frame of the delivery station, is operatively connected to platen lit by the illustrated bellcrank and lost-motion mechanism. Thus, reciprocation of the cylinder rod will in turn reciprocate the platen in a second direction, perpendicular to the direction of feed of the sack blanks into the delivery station. Platen 11 is carried on rollers 31 which run in guide-rails l5 and is guided laterally by thrust rollers M the reception ofa blank therein. During the blank feeding operation, each sack blank is thrown over lower plate 18 by feed rolls and is urged downwardly thereon by overlying rails ll7.

When platen 11 moves generally leftwardly in FIG. 3, upon extension of cylinder 112., a leading side edge of the blank will engage a stationary stop means or plate 16a while the platen continues to move under the plate. Simultaneously therewith, an opposite and trailing side edge of the blank initially enters opening 2t), defined by a rearward straight edge of plate 118 and an adjacent forward and tapered edge of plate 119. Continued leftward movement of the platen permits the blank to fully move through the opening and to fall through a large, horizontally disposed opening (not shown) formed through the stationary table of the delivery station and onto conveyor 7.

The integrated drive system for the machine is synchronized to permit the blank to fall onto the conveyor precisely, to have its trailing side edge engaged by a pusher plate 21 secured to the conveyor. The equally spaced plates are positioned in close linear alignment to maintain substantially high operating speeds during the continuous gluing and stitching operations performed at station 2. it is, of course, desirable to reduce the wasted stitch between the adjacent sack blanks to the lowest possible length.

Since it is further desirable to maintain the blanks as close together as possible on conveyor 7, the sack blanks must be fed downwardly onto the continuously moving conveyor belt at exactly the right moment. Such coordination is readily achieved by the synchronized movements of conveyors and 7, rollers it) and platen 11. In addition, the delivery station is constructed to prevent the inadvertent feeding of two sack blanks simultaneously onto plate 118 and conveyor 7.

In particular, should conveyor belt 4} and rollers it feed a trailing blank into the delivery station while the platen is reciprocating to feed a leading blank through opening 20, the trailing blank would at least partially fall onto plate 19. The leading side edge of the trailing blank would normally engage stop plate 11b to prevent it from interfering with the sequential feeding of the leading blank through opening 2i). Therefore, the feeding of a blank to conveyor 7 can only be accomplished when the platen is in its fully retracted, Fit}. 2 condition of operation wherein plate 118 is positioned to receive such blank.

if so desired, an intermittently actuated stop mechanism (not fully shown) could be positioned in the delivery station and forwardly of rolls MP to prevent the inadvertent feeding of a trailing blank therethrough until a leading blank has been fed to conveyor '7. The stop mechanism could comprise a movable arm or gate 21a synchronized with the movements of platen ill: and belt 7. In particular, such an arm or gate would move into a blocking position in front of the gap formed between rolls 10 until the leading blank has been fed to conveyor 7 and platen is returned to its FIG. 2 position.

The operations performed at stations l and 2 are preferably run at the same, synchronized speed, as dictated by the speeds of belts 4 and '7. Such synchronization may be accomplished, for example, by means of a pulse counter (not shown) operatively associated with belt 4 to count the number of sack blanks passing thereby during a predetermined time interval. The number counted can then be compared with a referonce value dependent on the linear speed of conveyor belt 7 for automatic adjustment of the speed of belt 4. Alternatively, the measured value of the feed speed of belt 4 can be used for regulating the speed of belt 7 and thus, also the number of lateral movements of platen 11 per a predetermined time interval.

What is claimed is:

1. An apparatus for feeding blanks comprising first conveyor means for moving a plurality of blanks in a first direction,

second conveyor means disposed vertically below said first conveyor means for moving said blanks in a second direction transverse to said first direction, delivery means, including a platen mounted for reciprocal movements in said second direction, for receiving said blanks from said first conveyor means and for continuously delivering said blanks to said second conveyor means, feed roll means rotatably mounted between said first conveyor means and said delivery means for receiving a blank from said first conveyor means and for impelling said blank into said delivery means, over said platen, and guide means disposed vertically above said platen for urging said blank downwardly onto said platen.

2. The apparatus of claim 1 wherein said guide means comprises at least one stationary rail converging downwardly toward said platen from said feed roll means.

3. The apparatus of claim ll wherein said platen comprises a pair of plates having adjacent edges thereof spaced vertically apart to define a down-feed opening therebetween extending in said first direction and vertically disposed above said second conveyor means.

4. The apparatus of claim 3 wherein said delivery means further comprises stationary stop means extending in said first direction and positioned vertically above said platen to permit said platen to move thereunder so that when said platen moves under said stop means a leading side edge of a blank resting on one of said plates will engage said stop means to permit an opposite side edge of said blank to enter said down-feed opening.

5. The apparatus of claim ll further comprising actuating means operatively connected to said platen for continuously reciprocating said platen in said second direction.

6. The apparatus of claim 5 wherein said actuating means comprises an extensible and retractable fluid actuator mounted on a stationary frame of said delivery means, a bellcrank pivotally attached at a first end thereof to a rod end of said actuator and pivotally mounted on said frame and lost-motion means connecting a second end of said bellcrank to said platen.

7. The apparatus of claim 1 further comprising tube forming means positioned adjacent to said first conveyor means for receiving and forming a continuous web of material into a tube and for cutting said tube into blanks and an end closure forming means positioned adjacent to said second conveyor means for forming an end closure on each of said blanks.

8. The invention of claim 1 further comprising stop means positioned between said first conveyor means and said feed roll means for selectively moving into a blocking position in front of said feed roll means to prevent the feeding of a blank to said feed roll means from said first conveyor means.

9. in a blank feeding station, a horizontally disposed platen reciprocally mounted in said station for movement in a linear direction, said platen comprising first and second plates defining vertically spaced apart edges defining a down-feed opening therebetween, disposed perpendicular relative to said linear direction, adapted to receive and guide a flattened blank therethrough.

10. A method for continuously feeding blanks comprising the steps of moving a plurality of blanks on a first conveyor in a first direction,

placing each blank sequentially on a platen, and

moving said platen in a second direction transverse to said first direction while simultaneously removing said blank from said platen, said removing step including the step of engaging an edge of said blank with a stationary stop member to hold said blank while said platen moves thereunder.

11. The method of claim it]? wherein said removing step includes the step of inserting said blank through an opening formed in said platen and permitting said blank to fall therebelow.

12. The method of claim W further comprising the step depositing said blank onto a second conveyor after removal thereof from said platen and moving said second conveyor in said second direction.

13. The method ofclaim 110 wherein said placing step includes the step of impelling said blank in said first direction and simultaneously guiding said blank downwardly onto said platen.

14. The invention of claim lib further comprising the steps of firstly forming a continuous web of material into a tube and cutting said tube into a plurality of blanks, while said tube moves in said first direction, and lastly forming an end closure on each blank.

15. An apparatus for feeding blanks comprising first conveyor means for moving a plurality of blanks in a first direction,

second conveyor means disposed vertically below said first conveyor means for moving said blanks in a second direction transverse to said first direction and delivery means, including a platen mounted for reciprocal movements in said second directiomfor receiving said blanks from said first conveyor means and for continuously delivering said blanks to said second conveyor means, said platen comprising a pair of plates having adjacent edges thereof spaced vertically apart to define a down-feed opening therebetween extending in said first direction and vertically disposed above said second conveyor means, said delivery means further comprising stationary stop means extending in said first direction and positioned vertically above said platen to permit said platen to move thereunder so that when said platen moves under said stop means a leading side edge of a blank resting on one of said plates will engage said stop means to permit an opposite side edge of said blank to enter said down-feed opening.

116. An apparatus for feeding blanks comprising first conveyor means for moving a plurality of blanks in a first direction,

second conveyor means disposed vertically below said first conveyor means for moving said blanks in a second direction transverse to said first direction delivery means, including a platen mounted for reciprocal movements in said second direction, for re cciving said blanks from said first conveyor means and for continuously delivering said blanks to said second conveyor means and actuating means, operatively connected to said platen for continuously reciprocating said platen in said second direction, comprising an extensible and retractable fluid actuator mounted on a stationary frame of said delivery means, a bellcrank pivotally attached at a first end thereof to a rod end of said actuator and pivotally mounted on said frame and lost-motion means connecting a second end of said bellcrank to said platen.

17. A method for continuously feeding blanks comprising the steps of moving a plurality of blanks on a first conveyor in a first direction,

placing each blank sequentially on a platen, and

moving said platen in a second direction transverse to said first direction while simultaneously removing said blank from said platen, said removing step including the step of inserting said blank through an opening formed in said platen and permitting said blank to fall therebelow.

18. A method for continuously feeding blanks comprising the steps of moving a plurality of blanks on a first conveyor in a first direction,

placing each blank sequentially on a platen, including the step of impelling said blank in said first direction and simultaneously guiding said blank downwardly onto said platen, and

moving said platen in a second direction transverse to said first direction while simultaneously removing said blank from said platen.

2 i t "i i

Claims

1. An apparatus for feeding blanks comprising first conveyor means for moving a plurality of blanks in a first direction, second conveyor means disposed vertically below said first conveyor means for moving said blanks in a second direction transverse to said first direction, delivery means, including a platen mounted for reciprocal movements in said second direction, for receiving said blanks from said first conveyor means and for continuously delivering said blanks to said second conveyor means, feed roll means rotatably mounted between said first conveyor means and said delivery means for receiving a blank from said first conveyor means and for impelling said bLank into said delivery means, over said platen, and guide means disposed vertically above said platen for urging said blank downwardly onto said platen.

3. The apparatus of claim 1 wherein said platen comprises a pair of plates having adjacent edges thereof spaced vertically apart to define a down-feed opening therebetween extending in said first direction and vertically disposed above said second conveyor means.

5. The apparatus of claim 1 further comprising actuating means operatively connected to said platen for continuously reciprocating said platen in said second direction.

10. A method for continuously feeding blanks comprising the steps of moving a plurality of blanks on a first conveyor in a first direction, placing each blank sequentially on a platen, and moving said platen in a second direction transverse to said first direction while simultaneously removing said blank from said platen, said removing step including the step of engaging an edge of said blank with a stationary stop member to hold said blank while said platen moves thereunder.

11. The method of claim 10 wherein said removing step includes the step of inserting said blank through an opening formed in said platen and permitting said blank to fall therebelow.

12. The method of claim 10 further comprising the step depositing said blank onto a second conveyor after removal thereof from said platen and moving said second conveyor in said second direction.

13. The method of claim 10 wherein said placing step includes the step of impelling said blank in said first direction and simultaneously guiding said blank downwardly onto said platen.

14. The invention of claim 10 further comprising the steps of firstly forming a continuous web of material into a tube and cutting said tube into a plurality of blanks, while said tube moves in said first direction, and lastly forming an end closure on each blank.

15. An apparatus for feeding blanks comprising first conveyor means for moving a plUrality of blanks in a first direction, second conveyor means disposed vertically below said first conveyor means for moving said blanks in a second direction transverse to said first direction and delivery means, including a platen mounted for reciprocal movements in said second direction, for receiving said blanks from said first conveyor means and for continuously delivering said blanks to said second conveyor means, said platen comprising a pair of plates having adjacent edges thereof spaced vertically apart to define a down-feed opening therebetween extending in said first direction and vertically disposed above said second conveyor means, said delivery means further comprising stationary stop means extending in said first direction and positioned vertically above said platen to permit said platen to move thereunder so that when said platen moves under said stop means a leading side edge of a blank resting on one of said plates will engage said stop means to permit an opposite side edge of said blank to enter said down-feed opening.

16. An apparatus for feeding blanks comprising first conveyor means for moving a plurality of blanks in a first direction, second conveyor means disposed vertically below said first conveyor means for moving said blanks in a second direction transverse to said first direction delivery means, including a platen mounted for reciprocal movements in said second direction, for receiving said blanks from said first conveyor means and for continuously delivering said blanks to said second conveyor means and actuating means, operatively connected to said platen for continuously reciprocating said platen in said second direction, comprising an extensible and retractable fluid actuator mounted on a stationary frame of said delivery means, a bellcrank pivotally attached at a first end thereof to a rod end of said actuator and pivotally mounted on said frame and lost-motion means connecting a second end of said bellcrank to said platen.

17. A method for continuously feeding blanks comprising the steps of moving a plurality of blanks on a first conveyor in a first direction, placing each blank sequentially on a platen, and moving said platen in a second direction transverse to said first direction while simultaneously removing said blank from said platen, said removing step including the step of inserting said blank through an opening formed in said platen and permitting said blank to fall therebelow.

18. A method for continuously feeding blanks comprising the steps of moving a plurality of blanks on a first conveyor in a first direction, placing each blank sequentially on a platen, including the step of impelling said blank in said first direction and simultaneously guiding said blank downwardly onto said platen, and moving said platen in a second direction transverse to said first direction while simultaneously removing said blank from said platen.