US2573944A

US2573944A - Method and apparatus for feeding blanks

Info

Publication number: US2573944A
Application number: US4013A
Authority: US
Inventors: Anderson Helmer
Original assignee: General Mills Inc
Current assignee: General Mills Inc
Priority date: 1948-01-23
Filing date: 1948-01-23
Publication date: 1951-11-06
Anticipated expiration: 1968-11-06

Description

NOV. 6, 1951 ANDERSON 2,573,944

METHOD AND APPARATUS FOR FEEDING BLANKS Filed Jan. 23, 1948 3 Sheets-Sheet 1 INVENTOR HELMER ANDERSON BY M6 4 ATTORNEY Nov. 6, 1951 H. ANDERSON 2,573,944

METHOD AND APPARATUS FOR FEEDING BLANKS Filed Jan. 25, 1948 5 Sheets-Sheet 2 my 5 E N J W 3 9; R O m 5. Na mm mm o o o .m MN m vfi E E v mm. v! 1 o o D V 0 o O o N N my mm A m: 5 n! Nb R N! a Q 5. E mg mm\ w\m0 N N0 7 1/92 W 11E m: P m2 Y M 0 a o 0 ll m g lu w o Nov. 6, 1951 I H. ANDERSON 2,573,944

METHOD AND APPARATUS FOR FEEDING BLANKS Filed Jan; 23, 1948 3 Sheets-Sheet I5 FIG. 7

FIG. 5

O 2 6 n3 3 O l [1 .5

i r I:

36 GI 66 Hal} 59 us A O /NVEN70R A O HELMER ANDERSON ATTORNEY Patented Nov. 6 1 951 PATENT oFFIcE Helm er Anderspn; Minneapolis, "Minn, assignor to General Mills, .I nc., a corporation of Dela 1 'Application January 1948,.Serial No. 4,013 A .il fi Glaimsl (01.: 271-) v 1' This invention relates ratus' for feedin blanks-and is more particularly concerned with the feeding of blanks which are slotted in such a'ma'nner as to provide flaps when the blank has been folded into'theshape of a carton.

Many devices have been employed in the past to feed such blanks. oneat'a time from one side of a stack, i. e.,"from the' topor from the bot-' tom of saidvstack." most'cases' such feeding is a simple matter because it takes place in a direction parallel toth e'slots; However, in certain cases it may be' des irable to 'feed' the blanks from the stack inga' direction at a substantial angle to the slots andili such a case thereis a definite probability that the flap portions of the blank being [fed will become interlocked with flap portions of anadjac'ent blank'so that either a plurality'of blanks will be 'fed instead" of the desired single blank or the flaps will bebent or tornf feeding such blanks.

oa method and appa- 8-8 of Fig. 1', and

With these disadvantages of the prior art in .It is a furtherobject to provide a method in 1 which blanks'may be fed one at a time from one side of a stack in a directiorr-substantially per} pendicular to'the'li'ne' of the slots in such a blank It is another object to provide a method of feeding slotted blanks in which interlocking engagement of the flaps-of the blank being fed with flaps of the adjacent blank is'positively prevented. v

Still another'object of the inventio'n is the pro- 1, with certainwportions broken away to showde1 tails of the operating mechanism. Y r

Fig. 4 is an enlarged view similar to Fig. 3of one of .the devices for achieving relative dis-v placement of the carton flaps.

Fig. 5 is an end view. of the device ,of Fig.=..1, certain portions. being broken away and other portions being omitted for clearness.

Fig. 6 is an'enlarged view showin details .of a flap-deforming .member, said member being shown in its inoperative position. e V Fig. '7 is aview similar to Fig. 6 taken onflthe line 1-1 -.of.-.Fig.' 4, with the, blank deforming member in its. operative position. 1 1;:

Fig. 8 is a partial sectional View on the line Fig. 9 is a partial perspective viewwof onelof the positioning, supporting; and guide members for the stack of carton-blanks, 1 .1;

I I General descriptionoj the method a ,:In .order to facilitate the understanding of the detailed description, of the apparatus, refererence ismade, to .Fig. 2 inv which a schematic showing is given of one manner in which the in vention maybe carried out. As shown in this figure. theinventionrrelates to the feeding of a slotted blank, 15.. For convenience a blanksuit: ablefor use as, a box .or carton has beenshown. Sucha blank includes cut or score lines lfi which effectively divide the; blank into four body portions each with a. corresp i pv o b ttom vision of apparatus 'to- "perform" this improved in process. V I

A further object is to provide a device which will feed blanks-one at a'time from'the-bottom of a stack in a; directionperpendicular 'to the slots in the blank and which shall include means for producingrelative'displacement between the portions of the blank being fed at the rear edge of eachslot of the blank and thecorresponding portions of the adjacent blank at the forward-edge of eachsuch slot. I j Other objects and advantages will be appar-' ent from the following specification in which a preferred embodiment of the invention has been described with particular reference to the attached drawings forming "a part of this application. In the drawings wherein like reference charac ters indicate like parts,

Figure 1 is a perspective View of a feeding apparatus embodying the present invention; cer-' tain of the parts being omitted forclearness. I Fig. 2 is a schematic perspective view showing how the apparatus performs the process of this invention.

j ss a s e ee -aw flap jateach end. Twoofthe alternate body portions ll may have a smaller cross sectional area than the other two alternate body sections .8 inord r hatp r iq sllm y serve as e ends and portions 18 as the sides of a rectangularcarton, when properly folded. Slots 1 9 serve to divide the edges of theblank into suitable top and bottom fiaps Bfl, ll I, 82, and 83 as shown in the drawing. -y 7 p It will beapparent that if aplurality ofsuch. blanks be arranged inra stack and if an attempt isrinade to feed the bottom-,most, blank'from the stack in 7 1 .6 direction of ,the arrow A in Fig. ,2, there will be a StIOllg probability that some of; the rearward flaps such as 8],,32, or 83 0f the bottom blank might become interlocked with the adjacent forward flaps of the next blank in the stack. As a.. result of such engagement both blafiks. m ht re f m-th t qm f th p e blank. Supports 43 have upwardly eurvedgmde;

portions 44? which project into the slotsbetweenl the flaps and serve toprevent inter-engagement offth flaps d ringthej feeding movement...j; In; otherwords, thefor'wa'rd edge of each flap 8 l ,'2',i

To assist the action of guides 44, suitablehap deforming members or fingers 85 may be mounted in such a manner as to push the forward pox-"- tions of flaps BI, 82, and 83 downwardly or'in a direction on the opposite side of supports43 from the remaining blanks in the stack. Thus these forward portions-or

flaps

81, 82, and 83' willbe so positioned that they will readily slide beneath guides 44 and supports 43 to prevent interlocking of'the fiapsas. desired. Thus the process of the present invention embodies broadly the idea of feeding the endblank of a stack in a direction substantially "perpendicular to the slots in the blank, whilesiinultaneously the fiap portions of the end-blank are guided along a'path which is laterally separated' fr'om the fiap por'tionsof the adjacent blank in the stack.

The details of one apparatus by which the methodof this invention may beperformed will now be described.

The supporting frame of the apparatus With particular reference to Figs.,l and 3, the apparatus of. -theinventi'on involves suitable side frame members llgand'l2. These side frame members, are joined at'the top by cross bars I4, l5, l6, and ll','which cross bars also support certain other portions'of the device. For example, at the central portion of the machine on cross bars 14 and I-are mounted two

longitudinal supports

18 and 19 which serve to carry the weight of the central portion of the stack of blanks to be fed. ll hese members are spaced apart as indicated at 2| fora purpose to bedescribed. At the forward end of the machine on cross 'b'arsf'lfi and H a further supporting plate 22'is provided. The rear end ofsupport' 22- is beveled as shown at 23. The forward portion of plate 22 slopes upwardly, as at 24, to a horizontal feeding platform or support 25. Above portio'n is a verticalend plate which serves as a positioning means fol one end of the-stack of blanks to be fed. I

The lower edgeofplate 25 is somewhat convex as shown-with the central-portion 21 of the-lower edge extending downwardly farther than the adjacent lateral portions 28. The spacing between edge 21 and plate 25 is just sufiicie'nt to permit the passage of a single blank when said blank is fe'd from the stack. The additional spacing between the lateral portions 28 of end plate 23 and the bed plate 25 is desirable'in' order to permit ready passage of the top and'bottom fiaps 'o'f the blank.

'End plate 26 is mounted on vertical supports 29 which in turn are carried by the inner members of longitudinal auxiliary frame members 3|.

There are two of these longitudinal frame members 3| at each side of the machine and theyare angular incross section (as shown in- Fig. 8) in order that'theymay-serve as guides and supports for some of the mechanismdescribed below. The". ends of frame members 3| are suitably joinedby cross pieces 32 and these name members "are further provided with horizontal plates'33 "fastened by bolts .34 to crossbars l4 and' lt'respec tively.

As Shown iIiFi. 1, plalii'fl altfi hfifv a rearwardly extending arm 35 which servesas a support for a rear cross bar 36 on which certain portions of the operating mechanism are mounted. =5 7 Additional longitudinal supporting bars 31 are mounted on cross bars 14 and I5 and these longitudinal bars serve to carry the supporting plates 38 which c'ooperate with central longitudinal -supports 1'8 and; [9 to carry the weight of the 10 stack of blanks. Plates 38 may be adjusted longi- 1 tudinallyofsupports 31 in order that they may be positioned at the rear end of the blanks and may assist'in supporting the rear end of the stack squarely so that the bottom blank may be fed from-the stack by. a suitable pusher.

Birmic supporting and guidingmeans V In order to hold the sides of the "stack of blanks in place, vertical supporting and-guide members designated generally as 39 have been provided.

Members 39,.as. shown in detail in Fig. 9, include an outwardly tapered upper. portion 4i and a vertical lower portion 42. Said guides 39 are adapted to be. positioned so that the horizontal distance between the vertical portions 42' Will just accommodate the width of the blanks being fed. "The, outwardly tapered u per portions 41 will thus act as guides .t'o facilitate the positioning of additional blanks onthe top of the stack.

At the bottom "of .guide's '39f there are horizontal supporting portions 43 .which are. adapted to be positioned beneaththe naps of the bottom blank, with one of sai suppormng. portions at the rear edge-bf each flap of 'said fblank. Supportingportiohs 4'3"are provided with the curved guides 44- which extend vertically upWardinto the slots. of the bottom blanks. in the "stack between adjacent flaps. of 's'aidblanks, as previously described in connection with Fig; 2;

b :In order that the vertical'position of'supports 43 may be adjusted 'guidesI'39 are provided; with bolts 45-.which engage. in slots 45 in the vertical supporting arms? 41. of suitable'braicket'members 4'8.

"B proper adjustment of. the height 5 of these supports 43=it is possible Ito have them carry a suitable'proportionof'the weight of the entire stack of blanks, so thatt'he stack will not rest too heavily oncentral-supports l8 and I9: and willf lie -ilatsacross. said. central supports without sagging or arching. V f

The lower horizontal portions-bf supporting brackets 48I are adjustablymounted on't he longitudinal auxiliary framemembers 4! .as shownin Fig. With'reference-to thisfigure, horizontal portions 48 of-the supportsare tightly engaged between lower and. upper clampmembers and 52 res pec tiyely;which are connected together by bolts- 53. The bottomclamp member 45 may have a portion of reduced cross-section as at-5'ladapted to fit the space between auxiliary framemembers 34 in order to-maintain the plate 49in proper alignment and guide- *it for rnovement longitudinally of -the machine. lt'willrbe apparent :from Figs: l, 3, and Q that-the support and guide members 4'3 and 44 may be adjusted vertically, laterally and longitudinally .of the rnachi-ne in order to accommodate themselves to'di-fferentsizes of the carton blanks and :to different spacings: of the slots in-such-bl-anks. -Thisreadyadjustability of the apparatus forms an important-part. of the present-invention.

In order. to. feed the bottomblanks successively from the sta ckthe followingmechanism'has been thickness of which corresponds to the thickness of the particular blank being fed. Thus, as the bar is pushed forwardly, its edge will engage the rear edge of the bottomblank of the stack and will push said blank forward-between the vend plate 26 and supporting platform 25 without movement of the next or adjacent blank in the stack.

The pusher 55 is carried by parallel chains 56 and is fastened to said chains by suitable brackets 51 (Fig. which may be interlockingly engaged with links of the respective chains. In order to hold the pusher 55 close to the supports I 8 and I9 and thus make sure that the pusher engages only the bottom blank, said pusher is provided with a downwardly extending projection of inverted T-shaped crosssection, the narrow portion of which is adapted to fit the space 21 between supports I8 and IS. The two lateral arms of extensions of the portion of T-shaped cross section engage beneath supports l8 and I5 and thus the pusher is maintained in proper aligmnent crosswise of the guides I8 and I9 and is also held downwardly against the top of said guides as desired, during the feeding movement.

It will also be apparent that the arrangement of pusher 55 and guides I8 and I9 is such that the pusher will move in a straight horizontal line along the top of the supports and will not be permitted to sag with the chains as would normally be the case if supports l8 and I9 were omitted.

Chains 56 are carried at their rear ends on idler sprockets 55 which in turn are mounted on a shaft 6|. Shaft 6! extends crosswise of the main frame of the machine and is journalled in bearings 52 which may be adjusted longitudinally of the machine by suitable adjustingscrews as shown at 63 (Figs. 1 and 3). This adjustment is desirable in order to avoid unnecessary slack in the chains.

The forward ends of chains 56 are carried on driving sprockets 64 which are suitably keyed to a drive shaft 65. Another driving sprocket 66is keyed to said shaft and is driven in turn by chain 6? from a suitable sprocket (not shown) on main shaft 68. This main shaft 68 is rotated to the left in Fig. 3) between the bottom edge- 21 of plate 28 and horizontal guiding and supporting surface 25. After the front edge of the blank passes a suitable distance beyond the'P end plate 26, it may be engaged by suitable feed rollers 13 and 14 of any desired type which-will pull the rest of the blank away from the stack and thus make it unnecessary for chains 56 to extend throughout the entire length of said stack. In other words, pusher 55 starts the blank from the stack and feed rollers 13 and M, which may be driven in any desired manner, completethe removal of said blank.

This

While 'I have shown a continuously operating driving mechanism with only one pusher 55 on chains 56, it will be obvious that this construction could be varied in a number of ways. For example, an intermittent drive which utilizes a standard one-revolution clutch might be employed if desired. Similarly, additional pushers 55 might be positioned on chain 56 so that more than one blank could be fed successively from the bottom of the stack with each complete revolution of the chain whether such motion of the chain be continuous or intermittent. Since such variations of the driving and feeding mechanism arewell understood in the art, no detailed description of each such modification need vbe given.

Flap deforming mechanism With the blank feeder as described up to this point, it will be apparent that sheets are fed successively from the bottom of the stack, as shown particularly in Figs. 2 and 3 and as described in the earlier portion of this specification. The rear portion of each flap of the bottom blank is carried on asuitable support 43 which is provided with the upwardly curved guide portion 44. These guide portions maintain the forward edge of each of the rear flaps of the bottom blank downwardly displaced with respect to the rear edge of each adjacent forward flap as the bottom blank is fed from the stack. This relative displacement is maintained during the feeding movement and thus the danger of interlocking engagement between the flaps of the bottom blank and the flaps of the adjacent blanks in the stack is avoided.

With certain types of material and suitable vertical adjustment of supports 43, the blanks may be held with the portions ahead of the slots raised in such a manner that the unsupported flap portions'at the rear of each slot will sag below the plane of the supports and can thus be fed forwardly without interlocking against the adjacent blank. It is also possible to feed certain blanks according to the invention even though the material does not sag as above described. In this case the guide portion 44 which extends into the slot will serve as a deflector to bend or cam the flap portion in rear of the slot to a downwardly displaced position which will avoid interlock. The guide portion 44 merges smoothly with the horizontal supporting surface 43 and thus this member acts as a deflector and separator, one face of which (e. g. the upper face) engages the stack ahead of the slot, and another face of which (e. g. the opposite face) engages the flap of the bottom blank behind the slot to guide said flap along a path relatively displaced with respect to the bottom or end of the stack. The guides could function in this manner in any stack, whether the blanks are horizontal or vertical.

In a preferred form of the invention, additional means are provided to insure the relative displacement of these bottom flap portions dur' ing feeding. Such means may take various forms, and by way of illustration I have shown one such flap deforming mechanism which will now be described.

To assist the relative displacement of the forward edges of flaps 8|, 82, and 83 flap deforming members or fingers 85 (shown schematically in Fig. 2) have been provided. The action of these flap deforming members 85 and the details of theirconstruction and mounting are best shown them below the level of guide .44 .and support43. Thus, it will be a simple matter for the bottom blank to be fed forward (1. e., to the .left in Fig. 4) with absolutely no possibility of inter-engagement of'its flaps 83 with the adjacent flaps182 of the other blanks in the stack.

. While it would be theoretically possible to mount the fingers 85 so that they would deflect only the bottom blank; I have found in practice that such an adjustment might result in failure to deflect the flaps in case the thicknessof a given blank varied from the thickness for which the machine was set. Therefore I prefer to adjust the fingers 85 so that they engage and bend a number of the bottom blanks as shown. Thus even though specific blanks vary in thickness, the bottom blank will always be deflected.

As shown in Figs. 6 and 7, each member 85 is pivoted at 86 to a bifurcated crank arm 81. Members 85 are similarly pivoted at 88 to another forked crank or lever 89. Pivot 86 is at the upper end of a member 85 as shown,whi1e pivot 88 is spaced at anintermediat e-- point on said member.

Crankarm 81 is integrallyconnected to a hub or bearing portion 9| which is pivotally supported by shaft 92 which extends lengthwise of the machine. Bearing portion 9| is freely rotatable on shaft 92 so that crank arm 81 may move through the desired are without movement of shaft 92,

The forked crank arm 89 is likewise integrally connected to a bearing or hub portion 93 which is mounted on another longitudinal shaft 94. In order that lever 89 may be firmly connected to shaft 94 and may be driven thereby the bearing portion 93 is of split construction as shown at 95, the two portions of the bearing being clamped together by a bolt 96 so that the bearing portion is firmly connected to shafted. Thus when shaft 94 is rotated back and forth or oscillated by mechanism described below, lever arm 89 will be similarly moved and will cause up and down movement of .deforming'finger 85. By loosening bolts 95 the position of fingers 85 may be adjusted longitudinally and vertically, inorder to correspond to the various adjusted positions of supports 39.

It should be notedthat the lever 89 is longer than lever arm 87. Because of this difference in length, there will be a tendency for the lower end of member 85 to be pushed inwardly against the stack of carton blanks as said member is moved downwardly from the position of Fig. 6 to the position of Fig. '7. Thus a compound movement of flap deforming members ,85 is obtained which is particularly advantageous for the purpose at hand. 7

Longitudinal shafts

92 and 94 are supported by

suitable bearing portions

91 and 99 on supporting brackets 29. These brackets 99 have horizontal base portions Hll which are adjustably mounted on the top of the machine as clamped on the longitudinal auxiliary framemembers 3! by means of clamping plates I94 and clampingbolts I93 which pass through slots-i|l2 in brackets ill! and engagext'he "platesiililfi; Plates I94 are substantially similar in cross sec-' tion to plates .49 shown'in Fig. 8 and are further provided withupwardly extending flanges which form a channel to maintain the bracket portions lDl' in alignment crosswise of the frame members 3|. By loosening bolts I93, it will be clear that the supporting brackets may be adjusted both laterally and longitudinally of the machine. These adjustments correspond to the similar adjustments of members 39 and in combination with the adjustments of fingers $5 and bearings 93, this makes it possible for the mechanism to be adapted to blanks of various width and blanks in which the slots are positioned at different longitudinal points.

The third bearing portion It]! for the Trear en of driving shaft 94 is identical with the otherv similarly numbered brackets but i positioned in archannel I95 of rear cross piece 36. A bolt I96 and clamping washer l9! are utilized to clamp this end bearing in the desired position. This bearing is adjustable laterally in the same manner as the others but it is unnecessaryto provide .for longitudinal adjustment of this particular member.

Since shaft 92 serves merely as a bearing for the upper crank arms 87, it need not be free to rotate and is preferably clamped in the bearing bracket 99. Shafts 94, on the other hand, serve as the driving means to oscillate the links 89 and members and therefore shafts 94 are mounted for free rotation in supporting brackets 99.

With reference again toFigs. 6 and 7, the lower end of flap deforming members 35 are notched as shown. These notches are'formed by a cutback portion me which extends in a substantially vertical direction and an adjacent cut back portion I99 which is sloped as shown. Thus .a hook is provided at the lower end of the member .85, the tip III of said hook being substantially parallel to the'direction of movement of member 85. The lower portion N2 of the member is slightly convex for engagement with the flaps 83. Intheupper or retracted position of the deforming members 85, as shown in Fig. 6, the lower ends of the members are clear of the stack of carton blanks. As the shaft 94 is rotated in a clockwise direction, these fingers 35 will be forced downwardly and inwardly against the stack and will engage the flaps of the lower blanks in the stack at a point justbehind the slots in the blank, i. e., at the forward edge of the flaps, with reference to thedirection of feed of the blank. The notched portion of fingers .85 will accommodate those flaps of the upper blanks which are not depressed by the end H2 of the finger.

It will be remembered that the flaps 82 just ahead of the slot in question are supported on member 43 and are thus incapable of down ward movementwith flaps 83. Thus a-relative displacement is obtained between the forward edges of flaps 83 and the rearward edges of flaps 82 which permits the bottom carton of the stack to be fed forwardly with no possibility of interlocking engagement between flaps 83 of the bottom blank and flaps 82 of the next to the bottom blank.

Driving mechanism for flap-deforming members In order to drive the shafts 94 I have provided crank-arm H3 at the rear end of each shaft as shown in Figs. 1, 3, and 5. These crank arms 3 are pivoted at I I4 to connecting links II5. Each connecting link II5 has an adjustable nut or turnbuckle portion II6 adapted to engage the upper threaded end II1 of a suitable connectingrod II8. g

The lower ends of connecting rods I I8 are connected by pivot pins I I 9 to universal links I2I (Fig. 3) which are further connected by pivot ins I22 to crank arms I23. Since the axes of pins H9 and I22 are at right angle to each other, it will be apparent that the linkage will adapt itself readily to the various lateral positions in which'shaft 94 may be adjusted.

Crank arms I23 each have split hub or bearing portions I24 which may be clamped together by bolts I25 so that crank arms I23 are firmly connected to a shaft I26 suitably supported crosswise of the machine frame. Shaft I26 has afurtlier lever or crank arm I21 extending in a direction substantially opposite to that of cranks I23. Said lever arm I 21 is connected to one end of a suitable return spring I28, the other end of which is fastened to a portion I29 of the main frame. Spring I28 tends to urge shaft I26 in a counter clockwise direction in Fig. 3 and thus urges connecting rods II8 upwardly to rotate shafts 94 so that the fiap deforming fingers 85 are urged in turn to their upper or retracted position as in Fig. 6.

To rotate shaft I26 in the opposite, or clockwise direction, a further crank arm I3I is provided, the lower end of said crank arm being pivoted at I32 to the adjustable end I33 of a longitudinal drive rod I34. The other end I35 of this drive rod is pivoted at I36 to the bottom of a supporting lever I31, the upper end of said lever being pivoted at I38 to one of the frame members I39. This supporting lever I31 carries a rotatable cam follower I'4I which engages the periphery of a cam I42 on main drive shaft 68. As shown in Fig. 3 cain I42 is divided into two p rtions, one of greater radius as at I43 and the other of smaller radius as at I44. Cam follower MI is urged constantly against the periphery of cam I42 by the action of spring I28 on crank I21 and shaft I26. Thus as drive shaft 68 is rotated, the cam follower I4I will be forced to the left in Fig. 3 by the larger portion I43 of the cam I 42 and will thus rotate shaft I26 in a direction which will cause fingers 85 to be depressed to the position of Figs. 3, 4, 5, and '7.

When the portion I44 of shorter radius reaches a point opposite cam follower I4I the various shafts and links will be moved by the action of spring I28 so that the fingers 85 return to the position of Fig. 6. Cam I42 is so oriented with reference to drive shaft 68 and the position of pusher 55 on chains 56 that the forward portions of the carton flaps will be displaced downwardly just before the pusher 55 engages the lowermost blank, and these flaps will be held in their down wardly displaced position until the feeding of the bottommost blank is substantially complete, so that there is no further possibility of interlocking engagement of any of the flaps.

In the particular mechanism shown the gearing is such that main drive shaft 58 will rotate more than once for each complete revolution of chains 56. It is contemplated that there will be a corresponding number of pushers 55 equally spaced around the chains. For simplicity, only one of the pushers 55 has been shown, and it will be clear that the particular number of pushers and the gear ratio employed will be a mere matter f choice for a skilled worker in th field.

In order that the carton blanks in the stack may be held firmly in position and flattened against the supporting surface so that the pushers 55 will engage the bottom blanksquarely and will not engage any of the adjacent blanks, a suitable weight member I45 has been provided. This weight is carried at the end of a lever arm I46 which in turn is carried by a bearing portion I4! pivoted at I48 to vertical supporting brackets I49 on rear cross piece 36.

From the foregoing description it will be ap parent that a device has been provided by which the method of this invention can be carried out and that this apparatus involves many advantages and improvements which combine to achieve the desired result and provide for eflicient feeding of slotted blanks. As explained in the foregoing description the blank feeding mechanism is fully adjustable so that it may accommodate carton blanks of various widths and lengths, and blanks which have different spacings between the slots which separate the top and bottom flaps. Furthermore, the invention is not necessarily limited to the feeding of blanks from the bottom of a stack, although this form is preferred because of the ease of replenishing the stack and because most carton folding machines are designed to receive blanks in a horizontal plane. Since many obvious changes may be made in the specific details of construction of the machine by persons skilled in this field, it is my intention that this invention shall include all such modifications falling within the scope and spirit of the attached claims.

Now, therefore, I claim:

1. The method of feeding slotted blanks laterally from one end of a vertical stack of superimposed horizontally extending blanks in which the slots extend transversely of the direction of feed, which comprises causing relative vertical displacement of the portions at the rear edge of each slot of a plurality of the end blanks and the corresponding portions at the forward edge of each slot of the adjacent blanks, and maintaining the relative vertical displacement of said plurality of blanks while feeding only the end blank from the stack.

2. The method of feeding slotted blanks from one end of a stack in which the slots extend transversely of the direction of feed, which comprises supporting the portions of the end blank at the forward edge of each slot, separately deforming a portion of the end blank at the rear edge of each slot in a direction to clear the forward edge portions of slots of the adjacent blank, and thereafter feeding said blank from the stack while maintaining said portions in deformed position until they have cleared the slot edges of adjacent blanks.

3. The method of feeding slotted blanks from one end of a stack in which the slots extend transversely of the direction of feed, which comprises holding a portion of the end blank at the forward edge of each slot to prevent lateral displacement of said forward edge portion, separately deforming a portion of said blank at the rear edge of each'slot in a direction to clear the forward edge portions of the adjacent blanks while the blanks are otherwise stationary, and then feeding said end blank from the stack and maintaining said portions in deformed position until they have cleared the slot edgesofadjacent blanks. Ti" 7 4. The method of feeding slotted blanks from one end of a stack in which the slots extend transversely of the direction of feed, which comprises supporting the portions of the blanksat the forward edge of each slot to prevent lateral displacement of said forward edges, separately deforming the portions of a plurality of end blanks at the rear edge of each slot in a direction to clear the forward edge portions of adjacent blanks, and thereafter feeding only the end blank from the stack while maintaining said portions 'of the remaining blanks in deformed position and thereby guiding the end blank clear of the slots of adjacent blanks.

5. In an apparatus for feeding slotted blanks from one end of a stack in which the slots extend "transversely of the direction 'of feed, the improvement which comprises a support engaging said end of the stack at the forward side of a slot, a flap deforming member, means f or moving the member against a portion of at leastthe end blank at the rear side of said slot and thereby displacing the portion in a direction perpen dicular to the plane of the blank and away from the stack to clear said support, and means for feeding said end blank from the stack while said portion is displaced.

6. Apparatus as described in claim in which said support and said deforming member are adjustably mounted both laterally and longitudinally for accommodation of different blank and slot dimensions;

'7. In an apparatus for feeding slotted blanks from the bottomof a stack in which the slots extend transversely of the direction of feed,'the improvement which comprises a support located under said stack at the forward edge of a slot, amovable deflecting finger engaging at least the bottom blank at the rear edge of said slot and bending said rear edge downwardly below said support prior to feeding movement of the bottom blank, and means for thereafter feeding said bottom blank forwardly from beneath'said stack while said edge ortion is bent.

8. Apparatus as in claim 7 in which said support and said finger are adjustably mounted both laterally and longitudinally for accommodation of different blank and slot dimensions.

9. In an apparatus for feeding slotted blanks from the bottom of 'a stack in which the slots extend transversely of the direction of feed, the improvement which comprises vertical deforming members located adjacent said stack at the rear edge of each slot, a pair of shafts extending longitudinally of the machine and disposed one above the other adjacent said members, crank arms on said upper shaft pivotally connected to an upper portion of each deforming member, crank arms on said lower shaft pivoted to a lower portion of each deforming member, means for driving one of said shafts from a first position in which said deforming members are raised and retracted, to a second position'in which said members engage and depress at least the bottom blank portions at the rear of each slot, and means forfeeding thebottom blank from said'stack while said one shaft is in said second position.

10. Apparatus as in claim 9, in which said upper crank arms are shorter than said lower crank arms. 7

11. Apparatus as in claim 9, in which said shafts are mounted: in bearing brackets, said brackets being adjustable transversely of 'thema chine for accommodation of blanks of different width.

12. Apparatus as in claim-,9, in which said crank arms are mounted for'adjustment longitudinally of said shafts for accommodation of blanks having different slot locations.

13. In an apparatus for feeding slotted blanks from the bottom of .a stack 'in'which the slots extend transversely of the direction of feed, the improvement which comprises supports located under said stack ahead of each slot, vertical deforming members located adjacent said stack at the rear edge of each slot, a pair of shafts extending longitudinally of the machine and disposed one above the other adjacent 'saidmembers, crank arms on said upper shaft pivotally connected to an upper portion of each deforming member, crank arms on said lower shaft pivoted to a lower portion of each deforming member, means for driving one of said shafts from'a first position in which said deforming members are raised and retracted, to a second position in which'said members engage and depressza't least the bottom blank portions at the rear of each slot to a level below said supports, and'means for feeding the bottomblank from said stack while said one shaftisin said second position.

14'. Apparatus as in claim 13, in which said shafts arermounted. in' bearing'brackets, said brackets being adjustabletransversely of the machine, and in which said crank armsare'mounted for adjustment longitudinally of said shafts, and said supports are adjustable: longitudinally, transversely, and vertically, for accommodation of different blanks. Y

15. In an apparatus for feeding slotted blanks from the bottom of a stack in which the slots extend transversely of the direction of feed, the improvement which comprises deforming members mounted adjacent said stack for movement betweena first position in which the members are retracted out of engagement with the stack and a second position in which the members are moved inwardly and'downwardly and thereby engage and depress the portions of at least the bottom blank at the rear of each slot, means for moving said members from first to second position, and means for thereafter feeding the bottom blank from the stack.

16. In an apparatus for feeding slotted'blanks from the bottom of a' stack in which the slots extend transversely of the direction of feed, the improvement which comprises deforming members mounted adjacent said stack for movement between a first position in which themembers are retracted out of engagement with the stack and a second position in which the members are moved inwardly and downwardly and thereby engage and depress the portions of a plurality of bottom blanks at the 'rear of each slot, means for moving said members from first to second position,'and means for thereafter feeding the bottom blank from thestack.

HELMER ANDERSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 2,449,690: Chapman Sept. 21, 1948