US2942739A - Strip stacker - Google Patents

Description

`une 28, 1960 o. E. HEARTs'n-:DT

STRIP STACKER 4 Sheets-Sheet 1 Filed Aug. 2, 195? OZQ Visa/'Medi June 28, 1960 o; E. HEARTSTEDT STRIP STACKER Filed mig. 2, 1957 4 Sheets-Sheet 2 June 28, 1960 o. E. HEARTSTEDT 2,942,739

STRIP STACKER Filed-Aug. 2, 1957 4 Sheets-Sheet 3 INVENTOR.

l @/ZMJW June 28, 1960 o. E. HEARTSTEDT STRIP STACKER 4 Sheets-She??I 4 Filed Aug. 2, 1957 INVENTOR. Oa E Hed/ded BY MM# KW United States. 'Patent STRIP STACKER tto E. Heartstedt, Skokie, Ill., assignor, by mesne assignments, to Continental Can Company, Inc., New York, N.Y., a corporation of New York Filed Aug. 2, 1957, Ser. No. 675,965

11 Claims. (Cl. 214-6) The present invention is directed to a new and improved automatic stacking apparatus particularly adapted for use in accumulating relatively thin sheets of flexible material in stacked relation, the sheets or strips being delivered to the stacker by a continuously operating conveyor which automatically deposits successive strips in the stacker, the stacker controlling movement of the strips therethrough into neatly accumulated stacked position.

It is an object of the present invention to provide a new and improved form of automatic stacker for use in `accumulating strips of flexible material in neatly piled condition, the strips being automatically conveyed to the stacker and delivered thereinto by a strip conveying means, the stacker controlling movement of each successive strip through the stacking area thereof to provide for neat accumulation of the same without damage thereto.

A further object is tol provide a new and improved stacking apparatus particularly adapted for use in accumulating strips of flexible material, the stacker operating substantially in a vertical plane and defining a stacking area at the top portion of which the successive strips are received for controlled dropping movement downwardly through the stacking area into accumulated stack formation, the stacking apparatus including means providing for initial bowing of each successive strip and further lmeans for maintaining the bowing thereof during the dropping movement within the stacking area to prevent inversion or position changing of the strips during their downward movement which might otherwise result in the imperfect accumulation of the strips as well as an unwanted degree of damage thereto.

Another object taken in conjunction with the foregoing is to provide a new and improved stacking apparatus of the type described wherein lthe stack formation and unloading functions of the stacker are fully automatic making it unnecessary for the operator to manipulate or otherwise control the positioning or movement of each successive strip during the stacking or unloading thereof, the apparatus further including automatically operated strip accumulation means which function during unloading to accumulate newly delivered successive strips in such a manner as to prevent interference'with the unloading of a completed stack of the same, the utilization of the strip accumulation means also eliminating the necessity of interrupted operation of the conveyor or strip forming apparatus from which lthe strips are received by the stacker.

Other objects not specifically set forth will become apparent from the following detailed description made in conjunction with the drawings wherein:

Fig. 1 is a side elevation of the strip stacker of the presx ent invention;

Fig. 2 is a front elevation of the strip stacking portion of the apparatus;

Fig. 3 is a sectional plan View taken generally along line 3 3 in Fig. l;

Fig. 4 is a fragmentary perspective of the top portion -of the stacker;

Patented June 28, 1960 Fig. 5 is an enlarged fragmentary end elevation of a portion of the operating means of the strip accumulation means forming a part of the apparatus of the present invention;

Fig. 6 is an enlarged fragmentary side elevation of the top portion of the stacking apparatus illustrating'in particular the strip accumulation means as viewed toward the right in Fig. 2; and

Fig. 7 is a fragmentary plan view of a portion of the strip yaccumulation operating means taken generally along line 7-7 in Fig. 6.

ln Figs. 1 and 2 a strip stacker 10 incorporating the principles of the present invention is shown mounted in its operative position at lthe end of a conveyor'structure 11. The conveyor is of knownV structural arrangement including a plurality of endless belts 12 advancedin the direction of the arrow in Fig. 1 toward the stacker 10 by a series of rollers 13 carried by a shaft 14 journalled at its ends in bearings 15. 'The' conveyor 11 is raised substantially from the -lioor surface 16 by a supporting framework which includes vertically directed end frame .beams 17 to which certain elements of the stacker 10 fare attached. A horizontally extending framework defined by spaced pairs of beams 18 extends from the conveyor supporting structure outwardly of the end thereof in supporting engagement with the elements of a strip accumulation mechanism 19 which forms a part ofthe stacker 10. in Fig. l the outermost end portion of the lowermost beam 18 is broken away to better illustrate the locatio of the mechanism 19. f

The stacker lil includes a vertically extending stacking area 20 which is defined at the top thereof by a pair of laterally spaced, inclined strip striking members 21 which are suitably attached at their uppermost ends to the framework of the conveyor 11. The lowermost or outermost ends of the rail-like members 21 are supported by a transverse beam 22 which is attached at its ends to the transversely spaced, uppermost side beams 18. The top surface of each of the members 21 functions Ias a striking surface for contact with an end portion of a flexible strip 23 when .the strip is delivered by the conveyor 11 from the end thereof into position over the top of the stacking area 26 in a manner to be described. The cross member 22 additionally carries an upwardly directed screen 24 which extends above the top horizontalv side frame members 18 near the outermost ends of the strip striking members 21 to contain each strip 23 in stacking area alignment for `end'portioncontact with the top surfaces of the members 21. l

The strip stacking area20 is of generally rectangularncross section and'isl partially defined by `transversely spaced posts 25 each fof which is suitably attached to its adjacent vertical` frame member 17 by angle iron connecting elements 26. The posts 25 define the rear surface of the stacking area 20 and the front sur-face thereof is dened by a pair of laterally spaced, vertically directed arms 27. The arms 27 each having integrally foiined therewith at the lower end thereof a mounting portion 28 which is horizontally directed and which includes sleeves 29 suitably keyed to a shaft 30 which extends through lixed bearings 31 near opposite ends thereof and into fixed engagement with transversely spaced gears 32. The shaft 30 further carries intermediate the bearings 31 and sleeves 29, additional sleevelike portions 33 which have attached thereto a horizontal plate 34 which defines a stacking surface on which a stack 35 (see Fig. 2) of strips 23 is accumulated. The sleeves 33 are fixed to the shaft 39 for pivotal movement therewith along with the vertical members 27 for stacker unloading purposes in a manner to be described.

The entire shaft assembly is supported by channel beams or plates 36 mounted on the lloor 16 and estabenligne their dead center'hanging position and the tendency of each band 54 to return to its dead center hanging position is increased thus resisting sucient straightening of each strip 23 to an extent that the central bow of the same will be retained. The slight give supplied by each yieldable side margin of the stacker is sufcient to prevent development of undue frictional interference between the ends of each strip 23 and the inner surfaces of the tapes 52 during downward movement of the strips 23 within the stacking area 20. This slight expansive action of the side margins, however, is insuiiicient to allowcomplete end-to-end attening of each strip 23 resulting in the eliminating of the central bow thereof, this bow being essential to prevent displacement or inversion of the strip during downward movement of the same.

As shown in Fig. 1, a number of the bands 54 may have their outer surface portions centrally cut out to define openings 57 therein to reduce the weight of each band 54 to an extent that the tape confining action of the same is inadequate to interfere with relatively free downward movement of a strip 23. Total weight reduction of this nature may be found necessary depending upon the gauge of the metal used in forming the bands 54 as it is necessary to provide each band with an uninterrupted inner surface portion for engagement with a tape 52. Preferably the width of the Iinner surface portion of each band 54 is almost equal to the width of each strip 23 to provide for adequately controlled downward movement of the same. Thus, if it is found preferable to reduce the weight of each band 54 and decrease the magnitude of tape confining action thereof, sections of the outermost pontions of each hand may be removed as illustrated to reduce this tape confining action to the extent desired.

As described, each successive strip 23 is automatically delivered into the top of the stacking area 20, the strips being centrally bowed by momentary striking engagement with the inclined members 21. The bowed condition of the strips is maintained during downward movement of the same within the stacking area by the contact with the transversely movable tapes 52. Each strip 23 ultimately contacts the top strip of the pile 35 supported by the plate 34 and in this manner a neat accumulation of strips 23 in undamaged condition automatically occurs. In order to unload an accumulated stack 35 of strips 23, suitable operating means are energized to rotate the shaft 37 through the belt and pulley arrangement and ultimately rotate the shaft 30 through the meshed gears 49 and 32. Upon proper rotation of the shaft 30, the stack confining members 27 are pivoted outwardly and downwardly toward the pallet 45 which is moved on the rails 42 into close association with the stacker 10 as shown in Fig. 3.

With outward and downward pivotal movement of the members 27, the accumulated stack 35 carried by the stack supporting plate 34 is tilted therewith by reason of the plate 34 being fixed for movement with the shaft 30. The stack 35 is pivoted out of the stacking area 20 into engagement with the top surfaces of the inclined rarnps 48 between which the arms 27 move in a downward direction. As shown in lFig. l, a stack 35 is transferred to the pallet 45 in inclined supported position between the cooperating surfaces of the ramps 48 and stack holding end plates 49. Continued downward movement of the arms 27 along an arc eventually clears the stack 35 from the inner surfaces of the arms 27 and the top surface of the supporting plate 34. As shown in Fig. 3, the forward edge of the plate 34 is provided with cut out portions 58 which allow the plate 34 to clear the inclined stack supporting plates l49 of the pallet 45. The stack 35 is thus fully transferred from the stacker 10 to the pallet 45 without displacement or damage of any of the strips forming a part thereof.

The cylinder 50 is actuated by air pressure or any other suitable means and the piston rod 51 is moved outwardly therefrom pushing the pallet 45 away from the front face of the stacker 10 to an extent that the outermost ends of the arms 27 clear the innermost end of the pallet 45 Ito allow return pivoting of the arms 27 -in an upwardly direction into their operative stacking area defining position as shown in Fig. l. The pallet 45 may then be disconnected from the end of the piston rod 51 and removed from the rails 42 for transfer to the closure cap forming machinery with an empty pallet 45 of similar construction being connected with the piston rod 51 and moved thereby back into cooperative relation with lthe stacker 10.

During unloading of the stacker 10, the strip accumulation apparatus 19 is operated to prevent interruption of continuous feedingof strips 23 to the stacker 10. The apparatus 19 as particularly illustrated in Figs. 2 and 6 comprises three pairs of reciprocating pin structures 59, 60 and 61. Each pair is defined by oppositely positioned, reciprocating pins 62 which move toward and away from one another into and out of the stacking area 20. 'I'he pins 62 are operated on `each side of the stacking area 20 by spaced shafts 63 and 64. As particularly shown in Fig. 6, each of the pins 62 carry spaced radially projecting shoulders 65 between which is received the bifurcated end 66 of a circular arm 69, the bifurcated portions of which receive therebetween the portion of the rod 62 intermediate the shoulders 65. The innermost end portion of each pin 62 is slidable in a sleeve 67 carried by the frame members forming a part of the structure of the stacker 10 and the outermost end is slidable in a fixed sleeve 68 also carried by the structural framework of the stacker 10. Each pin 62 is arranged for reciprocating movement relative to its sleeves 67 and 68 by actuation of a rocker arm 69 having formed integrally therewith the bifurcated end 66. Each arm 69 is fixed to one of the shafts 63 and 64 for oscillating movement therewith upon actuation of the strip accumulation mechanism 19. With the arrangement described, each pin 62 is operated in exactly the same manner.

Rocking of the shafts 63 and 64 is accomplished by an operating mechanism 70 carried in a housing 71 supported by the horizontal side frarne members 18 at the uppermost portion of the stacker 10. As particularly shown in Figs. 5 and 6, the strip accumulation mechanism 19 is operated by an air cylinder 72 which includes a reciproeating piston rod 73 attached to one end vof a rack 74 having a series of gear teeth engaged with a rotatable gear or pinion 75 carried by a depending stub shaft 76 which is suitably mounted in a housing 77 carried by the uppermosthorizontal frame member 18 adjacent thereto. The pinion 75 is rotatably mounted on the stub shaft 76 for rotation in a horizontal plane and is oppositely engaged with a series of teeth carried on the inner surface of a second rack 7 S slidable in the housing 71. The outermost end of the rack 74 is provided on the top with a series of teeth engaged with a gear 79 tixedly carried by the shaft 63. The innermost end of the rack 7S carries a series of teeth thereon which are engaged with a gear 50 fxedly carried bythe shaft 64.`

As shown in Fig. 6, the pins 62 are projecting into the stacking area 20 for accumulation of the strips 23 during unloading of the stacker 10. With operation of the air cylinder 72, the piston rod 73 is moved outwardly thereof to move .the rack 74 to the right as shown in Figs. 6 and 7 and this movement rotates the shaft 63 through the gear 79 in a counterclockwise direction moving the three rocker arms 69 carried thereby toward the right as viewed and causing the pins 62 associated therewith to be moved out of the stacking area 20. The pinion 75 rotates to provide for opposite movement of the rack '78 and opposite rotation of the shaft 64 with resulting opposite movement of the pins 62 positioned on the other side of the stacking area 20.V Operation of the air cylinder 72 from the position shown in Fig. 6 will retract Vthe pins 62 to complet'ely remove the same from the stacking area 20. Re-

verse operation of the cylinder 72 to withdraw the piston rod 73 thereinto, causes reverse operation of the elements described and movement of the pins 62 into projecting relation within the stacking area 20. f

In considering Figs. 2 and 6, projection of the pins 62 into the stacking area as illustrated in Fig. 6 will result in the accumulation of the continuous supply of strips 23 on the pinsV 62 in supported relation thereby. Each pair of pins 62 functions to sufliciently close off the top portion of the stacking area 20 to intercept successive strips 23 delivered thereinto from the conveyor 1-1. The strips are caught in their bowed condition bythe pins 62 and are accumulated thereon during unloading of the stacker 1G in the manner previously described. Upon completion of the unloading operation and the return of the members 27 into their vertical position, the pins 62 are withdrawn by operation of the mechanism 70 and the pile of strips accumulated thereby is allowed to drop through the stacking area 2t) into contact with the stacking plate 34. The strips delivered from this point on will fall directly from the conveyor 11 onto the top of the new stack 3S accumulated on the plate 34 without interference from the pins 62 which are in their retracted and inoperative positions.

t As previously described, the provision of a central bow to each strip 23 and the continued existence of this bow during dropping ofthe strip through the stacking arca 20 is of considerable importance. The bow is formed by the-inclined `members21 and it is essential to t retain this bow duirn'g accumulation of theV strips by the apparatus '179 for subsequent controlled dropping ofthe pair of Vstrip supportingelements 60 is vertically downwardly offset relative tothe remaining pairs 59 and 61.VV

This arrangement is particularly shown in Fig. `2 wherein a bowed stripV 23 is illustrated in broken lines as heldin its bowed condition by the strip accumulation. mechanism Y,

19. Thus, all of the strips 23 accumulated on the projecting pins 62 remain centrally bowed for subsequent conv trolled dropping through the stacking area 20. when the unloading operation is completed and the strip accumu-V lation pins 62 are` retracted out of the'stacking area 20.

'fore only such limitations should be imposed as are indicated in the appended claims.

Iclaim: Y I Vf' 1. A strip stacker for rcceivingreadily exible metallic strips from the end of a conveyor and stacking'the same, said stacker Vincluding a vertically directed stacking area, the top of said area being located relative to the end of said conveyor to receive thereinto said strips in a consecutive manner and in flat condition, said top being defined by transversely spaced strip striking surfaces which are contactedby the end portions of each strip upon leaving the conveyor, said strip striking surfaces being spaced from onev another a distance /which'is less than the fiat length Aof said strips, said strips being sufficientlyV iexible to bow centrally thereof upon contact with said striking surfaces for controlled dropping movement downwardly within said stacking area, and yieldable strip contacting means forming the side margins of said stacking area which are also spaced from one another a distance which is less than the at length of said Vstrips to be in engagement with the ends of each strip during the dropping thereof to maintain the central bow therein. v

2. A strip stacker for receiving readily flexible metallic strips from the end of a conveyor and stacking the same, said stacker including a vertically directed stackingarea the outer portion of which is defined by spaced upright stack conning arms, the top of said area being located relative to the end of said-conveyor to receive thereinto said strips in a consecutive manner and Vin dat condition, said top being defined by transversely spacedA strip striking surfacestwhich are contacted by the end portions of each strip upon leaving the'conveyor, said strips being suliiciently flexibleV to bow centrally thereof upon contact with said striking surfaces forcontrolled vdropping. movement downwardly within said stacking area, and yieldable side-margins forminga part of said stacking Varea which are in engagement with the ends of each striplduring Vthe dropping thereof tomaintain the central .bow therein, saidparms beingfpi-votally mounted at the bottoms thereof for movement away from said stacking area toward a fhorirontal plane, the bottomV of ,said stacking areatbein'g' strips from the end of a conveyor andvr stacking the same,

While the strip stacking mechanism of thea-.present in- Y vention has been described'iny connection with its use in .theV manufacture of metallic closure members such as 'ating'means such as the driving means for the unloading Ymechanism and Vthevair pressure supply Ymeans for posi- Y tioning movement of the pallet and Yoperation ofthe strip accumulating mechanism, can readily be Vsequentially or simultaneously yoperated,?as the case may be, by any Yknowntype of automaticcontrolmeans; Q'Ifhus, upon the accumulation' of Vstrips to'a predetermined extent within` the stacker, the various,drive-vmechanismsV maybe autop g matically placed into operation toy carry out the sequential stepsV ofjurdoadin'g and -strip accumulation Yduring unloading, The apparatus described is particularly adapted for automatic operation,4 it :being unnecessary to Y' interrupt continuous operation of the conveyor 11 in supplyingV successive strips V23 and thus interrupt operation of the strip forming machinery; The strips are accumu-Y lated and automatically unloaded in neat piles without i damage thereto resulting. in substantial time and material savings. t s

Obviously many modifications and variations oflthein vention as hereinbefore set forth mayI be made withoutY Vdeparting from the spirit and. scope thereof, and theresaid stacker including a vertically;Y directed stacking area, the top ofY said area being. located relative' to the: end of saidconveyor to receive-thereinto said strips inY a1 con- Y secutive manner andin flat condition, said top being ldefined by transversely spaced strip striking surfaces Ywhich are contacted by the end portions of each stripV upon leaving the conveyor, saidY strips being sufficiently flexible to' bow centrally thereof upon contact withk said striking surfaces Y for Vcontrolled dropping movement downwardly within said stacking area, yieldable side margins forming e Vpart of said stacking YVareaY whichlare in engagement with the-ends of each'tstrip during the droppingthereof tofmaintain the central bow therein, and strip accumulation means forming a partof-said stacker Ynear the top thereof,l Siaid accumulation meansVY including! reciprocating Ysurfaceswhich. move into said stacking' area to intercept vconsecutive strips delivered fom said-.,ccnyeyona'nd temporarily stack the saine duringg'unloading of, saidV stackv Ving arca.

4. A strip stacker for'receiyingreadily exible'nietallic strips from theY end of a conveyor, andstackingthe same, said stacker including a vertically directed stacking area the Vouter portion'v of whichjis defined? by *spaced* upright sta'clcconni'ng ar-msLjthe top of said area' being located reiative Vto the end of'said conveyor to-receive theretinto said strips Vin; aconseczutiveY manner and in flat condition,

said top being defined by transversely spaced strip striking surfaces which are contacted by the Vend portions of 'each strip upon leaving the conveyor, -sa'id strips being Y suiiiciently exible to bow centrally thereof upon contact with said striking surfaces for controlled dropping movement downwardly within said stacking area, yieldable side margins forming a part of said stacking area which are in engagement with the ends of each strip during the dropping thereof to maintain the central bow therein, said arms being pivotally mounted at the bottoms thereof for movement away from said stacking area toward a horizontal plane, the bottom of said stacking area being defined by a stack supporting surface which is mounted for tilting movement with said arms to tilt an accumulated stack of said strips out of said area for unloading, and strip accumulation means forming a part of said stacker near the top thereof, said accumulation means including spaced reciprocating surfaces which move into said stacking area to intercept consecutive strips delivered from said conveyor and temporarily stack the same during unloading of said stacking area, said reciprocating surfaces being vertically staggered to retain the central bow in each strip during temporary stacking thereof.

The stacker of claim 4 which further includes stacker operating means interconnected with said arms, said reciprocating means and said strip accumulation means to simultaneously operate the same during unloading of the stacker.

6. The stacker of claim l wherein said yieldable side margins of said stacking area are each dened by a plurality of vertically arranged lightweight bands of teardrop shape each of which is pivotally mounted for movement into and out of centered relation during downward movement of succesive strips, the inner surfaces of said bands being in positioning engagement with a vertically directed continuous band-like tape along which an edge of each strip slides during downward movement thereof, said bands resiliently backing up said tapes to maintain the central bow in each strip.

7. The stacker of claim 4 wherein said yieldable Side margins of said stacking area are each defined by a plurality of vertically arranged lightweight bands of teardrop shape each of which is pivotally mounted for movement into and out of centered relation during downward movement of successive strips, the inner surfaces of said bands being in positioning engagement with a vertically directed continuous band-like tape along which an edge of each strip slides during downward movement thereof, said bands resiliently backing up said tapes to maintain the central bow in each strip.

8. The stacker of claim 3 wherein the reciprocating surfaces of said strip accumulation means are pin-like members arranged in transversely spaced pairs in each of which the pin-like members reciprocate toward and away from one another on opposite sides of said stacking area, a central pair being vertically downwardly odset relative to the remaining pairs to retain the central bow in each strip during temporary stacking thereby.

9. The stacker of claim 2 wherein a movable pallet is operatively connected therewith by reciprocating means to receive a stack of strips during unloading of said stacker, said pallet having inclined spaced stack supporting ramps between which said arms are received to transfer a stack from said arms onto said ramps, the travel of said reciprocating means being adequate to move said pallet away `from said stacker to an extent to clear said arms relative to a transferred stack to allow pivotal return of said arms into stacking area defining position.

l0. The stacker of claim 2 wherein a movable pallet is operatively connected therewith by reciprocating means to receive a stack of strips during unloading of said stacker, said pallet having inclined spaced stack supporting ramps between which said arms are received to transfer a stack from said arms onto said ramps, the lowermost ends of said ramps having a stack holding surface positioned at substantially right angles thereto, the travel of said reciprocating means being adequate to move said pallet away from said stacker to an extent to clear said arms relative to a transferred stack to allow pivotal return of said arms into stacking area dening position.

1l. The stacker of claim 4 wherein a movable pallet is operatively connected therewith by reciprocating means to receive a stack of strips during unloading of said stacker, said pallet having inclined spaced stack supporting ramps between which said arms are received lto transfer a stack from said arms onto said ramps, the lowermost ends of said ramps having a stack holding surface positioned at substantially right angles thereto, the travel of said reciprocating means being adequate to lmove said pallet away from said stacker to an extent to clear said arms relative to a transferred stack to allow pivotal return of said arms into stacking area defining position.

References Cited in the file of this patent UNITED STATES PATENTS 2,017,044 Graf et al Oct. 15, 1935 2,333,479 Graf Nov. 2, 1943 2,647,670 Cox Aug. 4, 1953 2,707,060 Nawman Apr. 26, 1955 2,733,921 Downs Feb. 7, 1956 2,767,534 VNydegger et al. Oct. 23, 1956

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