US2753769A - Bag bottomer - Google Patents

Description

July 10, 1956 Filed March 9, 1955 E. E. BURROUGHS BAG BOTTOMER 7 Sheets-Sheet 1 INVENTOR.

July 10, 1956 E. E. BURROUGHS BAG BOTTOMER 7 Sheets-Sheet 3 Filed March 9, 1955 E BUREOUGHS- ATTORNEY-5.

July 10, 1956 E. E. BURROUGHS BAG BOTTOMER 7 Sheets-Sheet 4 Filed March 9, 1955 INVENTOR. E 0 WINE BUEROUGHS.

BY w d L W,

ATTOR/VEKS.

July 10, 1956 E. E. BURROUGHS BAG BOTTOMER 7 Sheets-Sheet 5 Filed March 9, 1955 i: 11 V IN VEN TOR. EDWIN E BUEIPOUGH-S.

I ATTORNEYS.

BAG BOTTOMER 7 Sheets-Sheet 6 July 10, 1956 E. E. BURROUGHS Filed March 9, 1955 July 10, 1956 BURRQUGHS 2,753,769

BAG BOTTOMER Filed March 9, 1955 7 Sheets-Sheet 7 I N V EN TOR.

51: W/NEBUEEOUGHS.

M i 1+, un

' ATTOIFWEVJ:

United States Patent BAG BOTTOMER Edwin E. Burroughs, Pensacola, Fla., assiguor to St.

Regis Paper Company, New York, N. Y., a corporation of New York Application March 9, 1955, Serial No. 493,135

Claims. (Cl. 93-22) This invention relates to improvements in bag bottom forming apparatus, and more particularly to apparatus for insuring folding over of the side flaps of a spread apart bag tube end accurately along selected lines.

In the formation of pasted bag bottoms by means of high speed machines which pull the individual bag tubes in succession sideways through a bag bottomer, and which operate upon the opposite extremities thereof to form the bottoms, some difiiculty has been experienced with respect to the accurate folding of the bottoms and thus with respect to accurate positioning of preformed sleeves which are to form the valve sleeves of the valved bag bottoms. Such a sleeve has a tendency to become slightly out of alignment or canted after it has been applied at high speed to the rapidly advancing partial-1y formed bag bottom. In bag bottomers of the aforementioned general type where the side fiaps are folded over to form the bag bottoms by means of foldover shoes past which the bag bottoms are pulled, there is a tendency for the trailing portion of the bag bottom to be slightly spread apart beyond its normal and desired dimension after such =foldover, and thus to be somewhat broader than the leading portion of the bag bottom. It has been found desirable, but not necessarily mandatory, in this type of bottomer to insert such sleeve at a trailing corner of the bag tube end, and because of the tendency of the trailing region of the bag bottom so to spread apart somewhat excessively as aforementioned, there is increased a tendency for the sleeve to become canted or slightly out of alignment.

One of the objects of the present invention is to overcome the difficulties aforementioned or to reduce same to negligible proportions.

Another object is to provide novel means for high speed bottoming of bag tubes whereby the finally bottomed bag tubes are provided with bottoms which are neither too narrow nor too wide but which are of a selected and uniform width.

A further object is to provide an apparatus of this general character which is capable of high speed use and thus well adapted for mass production.

Another object is to provide apparatus of this character which is of wide versatility because of its ability to accommodate a wide variety of bag bottom sizes and wherein adjustment of the apparatus to accommodate a new bag bottom size can be effected with substantially negligible down time or period of inoperation of the machine.

The invention, in one aspect thereof, is constituted by a bag bottom forming apparatus having a bag tube conveyor including grippers for consecutively gripping each of a plurality of bag tubes on the leading edge thereof and pulling same in succession along a common path through said apparatus in spaced relationship. Grippers for successive tubes are separated by a selected interval. The apparatus includes mechanism for spreading a tube end of each of such tubes moved by the conveyor and forming thereupon two side flaps, two end flaps, and two parallel bottom fold score lines. In combination with the above, there is employed supplementary conveyor means for conveying in succession a plurality of pairs of end fiap press elements in the same direction and at the same speed as the aforementioned bag tube conveyor. The press elements of a given pair are spaced at a distance substantially equal to the length of a bottom fold score line and corresponding press elements of any two successive pairs thereof are spaced at the aforementioned selected interval which separates said successive grippers. The supplementary conveyor means and the press elements moved thereby are constructed and arranged for successively pressing the end fiaps of each of the oncoming bags. Each end flap is pressed at the corresponding opposite termini of the two opposite bottom fold score lines thereon, said termini also defining the termini of a bottom width line Which is perpendicular to and between such score lines. Side flap folding means are also employed and are positioned for acting contemporaneously with such pressing of the end flaps by said press elements whereby all of the bag bottoms are formed at a precise and uniform width. If desired, and just prior to the pressing of the end flaps, a preformed valve sleeve can be deposited upon one of the end flaps of each tube in a desired position which will be maintained by its respective press element.

Various, further and more specific objects, features and advantages of the invention will clearly appear from the detailed description given below taken in connection with the accompanying drawings which form a part of this specification and illustrate, by way of example, preferred arrangements of apparatus for carrying out the invention. The invention consists of such novel combinations of features as may be shown and described in connection with the equipment herein disclosed.

In the drawings:

Fig. 1 is a perspective view of a schematic nature illustrating apparatus embodying one form of the invention;

Figs. 2a to 2k, inclusive, illustrative steps in the formation of a pasted bag bottom by means of the apparatus shown in Fig. 1;

Fig. 3 is a plan view on a relatively enlarged scale, as compared to Fig. 2, of a single end flap press element shown in pressing relation upon the end flap of a bag bottom;

Fig. 4 is a side elevation of a portion of the apparatus embodying the present invention;

Fig. 5 is an end view of the apparatus shown in Fig. 4;

Fig. 6 is a top plan view of the apparatus shown in Fig. 4;

Fig. 7 is a view of the righthand portion of the apparatus shown in Fig. 4 but illustrating certain details thereof which are omitted from the latter figure, Fig. 7 also illustrating certain conveyor means for removing the bottomed bag tubes from the bag bottonier;

Fig. 8 is a side elevation of a schematic nature illustrating means for effecting a final bag bottom pressing;

Fig. 8a is a front view of a main roller employed in the apparatus of Fig. 8;

Fig. 9 is a sectional view taken substantially along line 9-9 of Fig. 4;

Fig. 10 is a sectional view taken substantially along line Iii-10 of Fig. 4; and

Fig. 11 is a sectional view taken substantially along line 1111 of Fig. 7.

Referring now to the drawings, with particular reference to Fig. l, the present invention includes travel- 3 ing end flap press means 26 which act in combination with and form a part of a bag bottomer machine 21, the end flap press means operating principally during the side flap foldover period, that is, during the time that the side flaps of the spread bag tube end are being folded over to form the bag bottom.

A bag tube such as 22, which is .one of a succession of bag tubes, is pulled in the direction of the arrow 23 by means of clamps 24 and 25 which are secured in the usual fashion to a pair of endless sprocket chains as and 27, respectively.

Such bag tubes are automatically fed to the apparatus preferably by means of an automatic feeder 23 which in sorts the bags in timed relationship into the grippers, such as 24- and 25, whereby the tubes are pulled sideways through the machine.

Each of the bag tubes is acted upon by the bag boa tomer, that is, by the several units of the bag bottomer to form the bag bottoms on opposite extremities of the tube as shown in Figs. 2a to 21', inclusive.

In the latter figure, namely Fig. 21', the sleeve is plied at the trailing corner .of one extremity of the partially formed bag bottom although, of course, it is not mandatory to apply such a sleeve.

During the formation .of the bottom, as shown in Figs. 2a to 21', as will be more fully explained hereinbeiow, a pair of parallel bottom fold score lines 2-9 and 38 (Fig. 2e) are formed which are preferably equidistant from a main or primary center score line 31. The parallel bottom fold score lines 29 and 3%) are those about which side flaps 32 and 33 are to be folded over to form the bottom.

After the bottom has been spread open and such side flaps have been partially folded, for example, as shown in Fig. 2h (the latter folding not being essential to the invention), a pair of traveling press or hold-down elements 34, 35, as shown in Fig. 2 are pressed transversely down upon end flaps 35 and 37 of, for example, the lefthand bag tube end, as viewed from the automatic feeder 23, it being understood, of course, that similar hoid-down elements may be pressed against the opposite end flaps at the opposite end of the tube. Press elements .34, 55 :are generally of bar-like configuration having pressing faces to be described more fully herebelow.

Referring again to Fig. 2e and also to Fig. 3, it will be noted at .the leftha-nd extremity of the bottom fold score lines 29, 30., there exists an imaginary line or meridian designated by the numeral 4t) which comprises a bottom width line. This line exists between the left-hand terminal points 2% and 39a of the bottom fold score lines 29 and 36).

Similarly a righthand bottom width line 41 (Fig. 2c) is formed between the terminal points 29b and 3% at the righthand extremities of the bottom fold score lines 2% and 30.

In order to achieve the object of the present invention, the hold-down or press bars should press down upon the end flaps 36 and 37 in the regions immediately adjacent the extremities of the lines and 41.. That is, the hold-down bars do not necessarily have to press directly along the lines 46 and 4-1 but should press the end flaps in the regions of the extremities of such lines thereby to facilitate and make more accurate the folding over of the side flaps 32 and 33.

Suitable novel conveyor means are provided for mounting the hold-down bars 34 and 35 aforementioned, which means will be described more fully hereinafter.

Accordingly, each extremity of the bag tube is pressed downwardly, as shown in Figs. 2 and 2k, during the foldover of the side flaps, and thereafter the bag tube is, of course, directed out from under the press bars and the bag bottom is pressed by suitable means, for ex ample, as shown in Pig. 8. Such'means are generally designated at 42 in such figure.

The general operation of the apparatus has been ded scribed above. Now again reverting to Figs. 1, 2 and 3, there will be further described additional details of the bag bottoming machine.

After a bag tube, such as 22, has been fed from the automatic feeder 2% into the grip of a pair of cooperating grippers 24, 25 of the main bag tube conveyor 26, 27, the tube is passed beneath a pair of slitters 43, 24 which are positionedover the opposite extremities thereof and which form the slits 4-5 comprising one pair of slits on each extremity, as shown in Fig. 2a.

Thereafter the following takes place in succession:

Main or center score lines 46 are formed, as shoen in Fig. 2b., by the center or main scorers 47 (Fig. l);

The opposite extremities of the bag tube are bent (Fig. 20) by the end bender units 48.;

The tube ends thereafter are preliminarily opened by preliminary opener units 49; thereafter such ends are spread and the side and end flaps formed by the spreader units 50 following which the now spread and partially formed bag bottom is pressed by presser units 51.; the effect of such preliminary opening, spreading and pressing being illustrated in Fig. 2d;

Thereafter the aforementioned bottom fold score lines 2) and 34) (Fig. 2e) are formed at each extremity of the bag tube by means of the bottom foid score line :units 52 whereby the imaginary bottom width lines as and can be visualized in the same figure;

Thereafter adhesive or paste is applied to selected areas of the now spread tube ends by means of pastor units 53, the position of such paste areas being indicated in Fig. 2f;

Thereafter the side flaps 32 and 33 are bent upwardly through 90, as illustrated in Figs. 2g and 211, by means of side flap bender unit 54;

Following this a sleeve applicator 55 deposits a sleeve 55a in one of the corners of the tube end, as illustrated in Fig. 2-1, preferably in one of the trailing corners, and in the form shown in the 'lefthand trailing corner, as viewed from the feeder 28;

Thereafter the aforementioned end flap press means 25 engages the tube end for pressing downwardly upon the opposite cndflaps an, 37, as shown in Fig. 2], the pressing occurring by the action of the aforementioned press bars 34, 35 which are urged toward an endless belt 56 therebeneath, there being one such belt on each side of the bottomer, it being understood that the tube end is inter posed between such end flap press elements 34, and the respective end-less belt. As is best shown in Fig. 6, a side flap foldover unit '57 is situated beneath each of the press units 29 for the purpose of folding first one of the side flaps over into the plane of the bag bottom and thereafter the other side flap over the first one thereby to form the bag bottom as shown in Fig. 2k, this occurring during the operation or pressing action of the press bars 34 and 55. The force of gravity urges the chains and press bars secured thereto down upon the bag tube ends resting upon the belts '56. A firm support may be positioned beneath each belt 56 to prevent it from sagging.

Thereafter the now folded bag bottom is directed onto further bag conveyor means '58 (Fig. l) which has associated therewith the aforementioned bag bottom pressing means 4-2 which effects the final pressing of the bag bottom and delivers the completed bags through an outlet 58a.

In my U. S. Patent 2,579,047, granted October 2, l, and in my copendi-ng application Serial No. 422,575, there are shown bag bottom forming uni-ts which may be similar to the following units herein mentioned: 43, 47, as, 49, 5t 51,, 52, '53 and '55.

Referring now to lFi-g. 3, it will be seen that the width of the bag bottom is determined by the dimension between the points 29a: and 3%, the line 4%) therebetween, as aforementioned, being designated the bottom width line, there being an analogous line at the opposite extremity of the same bag bottom. in normal commercial practice, the variation in the widths of bag bottoms illustratively is presently between about 2 /2 inches up to about 5 /2 inches, although, of course, these are not necessarily fixed limits. Consequently, it is desirable to have press or hold-down bars which are capable of accommodating any width of bag bottom, within reasonable limits, and which bars can be easily adjusted in position with minimum effort and time. The bars 34 and 35 are adjustable as to the distance therebetween in a novel and rapid manner, as will more fully appear hereinafter, not only in order to accommodate bag tubes of differing widths, but also to accommodate bag bottoms of differing widths. In order to accommodate such varying widths of bag bot toms, each of the bars, such as 34, as is well shown in Fig. 3 is provided with a protuberance, for example, 34a having preferably a fiat bottom face for pressing down upon the end flap and which is in the shape of an isosceles trapezoid as formed between the points 59, 60, 61 and 62. The dimension between the points 59 and 62 preferably is somewhat greater than maximum bottom width which is to be accommodated, and accordingly the dimension between the points 60 and 61 is somewhat less than the smallest bottom width to be accommodated. It will be seen from the top plan view of the isosceles trapezoid 34a of Fig. 3 that it is provided with the edges 63 and 64 which respectively are between the points 59, 60 and 61, 62. Such edges 63 and 64 comprise the non-parallel and equal sides of such quadrilateral and thus are able to press satisfactorily downwardly upon the region of the termini of the bottom width line 40- or alternatively, to press down in the region of the termini 29a, 30a of the bottom fold score lines 29 and 30 providing the length of such line is within the selected limits. It is not entirely necessary for the press bars to press downwardly over a substantial area in the region intermediate such termini but it has been found to be desirable and, of course, the pressing down of such bars upon diagonal fold lines 65 and 66 over at least a portion of the length thereof has a beneficial effect in the pressing of the end flap but again is not absolutely necessary in view of the prior pressing of such diagonal fold lines by means of the presser units 51.

Referring now to Figs. 1 and 4, there will be described one of the aforementioned units 20 which embraces several pairs of press bars and also the conveyor means therefor. Such conveyor means are of the endless band type, each such band comprising, in the form shown, a sprocket chain.

In order to permit easy adjustment of the dimension between the two press bars comprising any pair thereof, such as bars 34 and 35 (Fig. 2f), I have found it desirable to secure the opposite extremities of one of the bars 34 to appropriate opposite points of a first pair of spaced endless conveyor chains 67, 68 (Fig. 1) and to secure the opposite extremities of the other hold-down or press bar 35 to appropriate opposite points of another pair of endless conveyor chains disposed between the first pair, such second pair being designated 69 and 70 (Figs. 1 and 2 Thus it is possible to adjust the aforementioned dimension between the bars 34 and 35 by, for example, loosening a hub clamp for one of the pairs of chains, e. g. 69, 70 and shifting same to the desired adjusted position. It is, of course, understood that the endless conveyor chains 67, 68 and 69, 70 pass over suitable sprocket wheels in a manner to appear more fully hereinafter.

Further although only one of the press units 20 is fully described herein, it is understood that the opposite unit is analogous thereto.

There are secured to the outermost pair of chains 67, 68 four long press bars each of which is somewhat longer than each of a corresponding number of short press bars which are secured to the innermost pair of endless conveyor chains 69, 70. I have found it'desirable to secure four of such bars to each of such pairs of chains although it is, of course, possible to employ a difierent number, it being understood that the same number of press bars for the first pair of chains is employed upon the second pair.

In the form shown in the drawings, the four long press bars secured to the chain pair 67, 68 are designated 34, 34a, 34b and 340. These long bars cooperate respectively with the following short press bars 35, 35a, 35b and 35c which, as aforementioned, are secured to the inner pair of endless chains 69, 70.

Referring now to Figs. 1, 4, 5 and 6, further details of the press unit 20 will now be described, together with the relationship thereof to the main bag tube conveyor 26, 27. The latter two elements 26 and 27 preferably comprise sprocket chains which respectively pass over sprocket wheels 26a, 26b and 27a, 27b (Fig. 1). There, of course, are provided suitable guide rails or supports beneath each of the upper runs of the endless sprocket chains 26, 27 for supporting same as they pass through the machine. Such rails, together with analogous rails situated above the lower runs of such chains, will be described below in connection with Fig. 9.

Referring again to Figs. 4, 5 and 6, each of the chains 67-70, inclusive, passes over suitable sprocket wheels. For example, the innermost chain 67 at its lefthand extremity (Fig. 6) passes over the single relatively large sprocket wheel 71 and, at the righthand extremity or outlet extremity thereof, passes over a pair of superposed sprocket wheels 72 and 73 which are respectively mounted upon an upper shaft 74 and a lower shaft 75, such shafts being mounted in suitable bearings and having respectively secured thereto driving gears I6 and 77 via which power is communicated from a main drive to be explained below.

Analogously, the opposite chain 68 of the pair 67, 68 passes at one end over' a relatively large sprocket wheel 78 (Fig. 6) and at the other end a pair of smaller superposed sprocket wheels 79 and 80 which are respectively mounted upon said shafts 74 and 75.

The endless sprocket chain 69 in turn is mounted at one end upon a single relatively large sprocket wheel 81 and at the other end upon two smaller sprocket wheels 82 and 83 respectively mounted on such shafts 74 and 75. Likewise the other conveyor chain 70 of this pair (69, 70) is mounted upon large sprocket wheel 84 at the lefthand extremity thereof and at the other extremity upon the sprocket wheels 85 and 86 also respectively mounted on the shafts 74 and 75.

The advantage of the particular type of mounting of such chains 67-70, inclusive, is to facilitate the adjustment of the dimension between any two cooperating press bars, such as 34 and 35. This can be effected as follows:

The gears 76 and 77 are secured to their respective 'shaftsby clamp hubs 76a and 77a and thus in order to disconnect either one of them it is a simple matter to loosen the respective clamp. Each of the relatively large sprocket wheels 71, 78 and 81, 84 rotate freely upon their respective shafts. However, this is not so of all of such smaller sprocket wheels, such as 72, 73. That is, the pair of sprocket wheels 82, 85 are freely rotatable upon the shaft 74 whereas the coaxial sprocket wheels 72 and 79 are keyed to such shaft and thus rotate therewith. The converse situation is true with respect to the shaft wherein the sprocket wheels 33, 86 are keyed to such shaft 75 whereas the relatively small sprocket wheels 73, rotate freely thereupon. This construction thus permits, by loosening, for example, the clamp hub 76a, the shifting of the outermost pairs of chains, namely, 67, 68, with respect to the relatively stationary chains 69, 70. And conversely, if it is desired to make the adjustment by means of the hub 77a, the latter may be loosened and consequently the innermost pair of chains 69, 70 can be shifted and the press bars thereupon can be shifted therewith. Thereafter, of course, the pertinent 7 clamp hub is tightened when the desired adjustment has been made.

Power is communicated to the various conveyor chains 26, 27 and 67-749, inclusive, by the following gear trains: A gear 87 in the lower middle portion of Fig. 4 is driven by suitable power means (not shown) and communicates power to the aforementioned gears 76, 77 (Fig. via two idler gears 83, 8.9, the latter meshing with a gear 9b which in turn meshes with :a gear M, the latter communicating torque to a gear '92 on the shaft 93 on which is a further gear 94 which in turn meshes with both of the aforementioned gears 76 and 77.

The righthaud endless belt 56, as shown in Fig. 1, is well illustrated in Fig. 7 for passing beneath the region over which moves the several press bars. Cooperating with such rightha-nd endless belt 56 and moving thercwith at the same speed are the righthand press bars 34, 35 and 34a, 35a, and so on.

Brcferring to Fig. 5, Ihave found it desirable to be able to adiust the side flap bend-up device to accommodate bag bottoms of widths having a dimension within the range of a small dimension 95 and a large one 96. Consequently, it is desirable to be able to adjust, with respect to the bag botto 3. center line, the side flap bend-up devices and to this end suitable manually adjustable side flap bend-up means, as shown for example at 97, can be employed and which can be clamped into position by means of suitable hand clamps, one of which is shown, for example, at 98.

The distance of the side flap foldover shoe 57, which embraces two separate shoes 57a and 571), above the endless belt 56, can be adjusted by means of manually controlled knobs 99 and 1th (Fig. 4).

Referring to Fig. 7, a guide belt 101 passing over rollers i 52 and 1 33 may be provided interposed between the righthand extreme region of the two opposite endless belts 56, reference being bad to Fig. 6 to indicate such position. Such belt 191 guides the bottomed bag tubes onto the eXit or outlet belt means 5% (Fig. l and Fig. 7) which consists of the following belt system:

A main exit belt 1-134 which over the initial portion thereof cooperates with a superposed belt 195 for directing the bottomed bag tubes into the aforementioned bottom pressing means 42. The belt 1%, for the pressing operation, passes over a relatively large roller lilo over a portion of the periphery of which, preferably about l8t,-, there is pressed a second belt 197 mounted as shown in Fig. 8.

Referring now to Fig. 9, the elements for bending upwardly and thereafter holding the side flaps in their upwardly bent condition are well illustrated at 108 and 166*, such elements comprising parts of the aforementioned side flap bender unit .54. Elements 3&8, 169 are mounted respectively upon axially shi'ftable shafts 110 and lift which are clamped, respectively by means of said clamping device 98 aforementioned and also 112, in desired positions, it being, of course, understood that they can be moved toward or away from one another as desired by suitable adjustment of such clamping means 3'8 and 112.

Also well shown in Fig. 9 are chain guide rails 113 and lid for supporting the upper runs of the outermost conveyor chains 67, 68 and further there are shown chain rails E and I116 for supporting the upper run of the inner pair of chains 69, 70.

Analogously there are provided chain rails 117 and 113 for guiding the lower runs of the chains 6'7, 66, respectively, and the rails T119 and 126 for the lower runs of the innermost pair of chains 69, 7 respectively.

Referring again to Figs. 1 and 4, the interval between any two successive grippers on the main bag tube conveyor 26, 27, such two successive grippers being shown at 24 and 24a, must be the same as the interval between the press bars 34-, 34a, of Fig. 4. Bars 34 and 34:: comrise corresponding bars of two successive pairs thereof.

By virtue of this relationship of intervals, the press bars are brought into proper phase relationship with the encoming bag tubes and, of course, are moved therewith at the same speed. That is, the speed of the conveyor chains which move the press bars is equal to the speed of the main bag tube conveyor 26, 27 and also to the endless belts 56.

What is claimed is:

l. In an automatic bag bottom forming apparatus havlug a bag tube conveyor, including spaced gripping means for consecutively gripping each of a plurality of bag tubes on the leading edge thereof and pulling same in succession relative to said apparatus in spaced relationship separated by a selected interval, mechanism for consecutively spreading a tube end of each of such tubes moved by said conveyor and forming thereupon two side flaps, two end flaps, and two parallel bottom fold score lines, the combination therewith of a plurality of pairs of end flap press elements, supplementary conveyor means for conveying in succession such plurality of pairs of press elements in the same direction and at the same speed as the aforementioned conveyor, the press eleen-ts of a given pair being spaced at a distance substantially equal to the length of a bottom fold score line, supporting means for said ends situated adjacent the path of said press elements for providing a backing against which portions of such end flaps can be pressed, said supplemen tary convey-or means and press elements being constructed and arranged whereby said elements successively press the end fiaps of each of the oncoming bags in the region of corresponding opposite termini of .two opposite bottom fold score lines, corresponding press elements of any two successive pairs thereof also being separated by the same aforementioned selected interval.

2. In an automatic bag bottom forming apparatus having a bag tube conveyor, including spaced gripping means for consecutively gripping a plurality of bag tubes each on the leading edge thereof and pulling same in successi-on relative to said apparatus in selected spaced relationship, mechanism for spreading the tube end of each of the tubes moved by said conveyor and forming there upon two side flaps, two end flaps, two bottom fold score lines, and two opposite bottom width lines, mechanism for applying adhesive consecutively to the spread tube cards upon selected areas thereof, the combination therewith of a plurality of end flap press elements, supplementary conveyor means for conveying in succession such press elements in the same direction and at the same speed as the aforementioned bag tube conveyor, such press elements of any given pair thereof for acting upon the two end flaps of a given bag tube being spaced. at a distance substantially equal to the distance between two such opposite bottom width lines, said conveyor means and press elements being constructed and arranged where by each of said elements press downwardly upon its respective end flap in the region of the termini of a bottom width line.

3. In apparatus of the class described for automatically forming bag bottoms upon bag tubes, such apparatus having a bag tube conveyor including means for gripping a plurality of tubes on the leading edges thereof and pulling same transversely thereof through such apparatus thereby moving same in spaced relation and in succession relative to bag bottom forming units of such apparatus, such units including means for opening and spreading along a tube end center line at least one end of each oncoming bag tube thereby to form upon each a pair of end flaps each having a pair of diagonal fold lines, and also to form a pair of side flaps, means for forming on such spread tube end a pair of parallel bottom fold score lines parallel to the direction of motion of said bag tubes and substantially equally spaced from such center line, said parallel bottom fold score lines each terminating at each end thereof intermediate the extremities of its respective diagonal fold line, the terminal points of the parallel bottom fold score lines upon a common end flap being located along a line which is substantially perpendicular to the path of movement of the bag tubes thereby forming an end flap bottom width line for each of said end flaps, characterized by a plurality of pairs of end flap press elements, conveyor means for moving in succession such press elements, the latter extending transversely of each of the oncoming end flaps of each oncoming bag tube, the press elements of each pair thereof for acting on a given tube end being spaced upon such conveyor means at a dimension substantially equal to the distance between the opposite termini of the bottom fold score lines of such tube end, each such element being constructed and arranged for pressing each end flap substantially at the two terminal points of the bottom width line of such end flap, and side flap fold means for acting consecutively upon the tubes during such pressing by said press elements whereby one of said side flaps is first folded along its respective bottom fold score line and thereafter the other side flap is folded over the first one also along its respective bottom fold score line.

4. ln apparatus for automatically forming bag bottoms upon bag tubes, such apparatus having a bag tube conveyor including means for gripping a plurality of tubes each at the leading edge thereof and pulling same through such apparatus thereby moving same in spaced relation in succession relative to the bag bottom forming units of such apparatus, such units including means for opening and spreading at least one end of each oncoming bag tube thereby to form a pair of end flaps and a pair of side flaps thereupon, means for forming on each such spread tube end a pair of parallel bottom fold score lines parallel to the direction of motion of said bag tubes and equally spaced from the center line of the spread tube end, the terminal points of the parallel bottom fold score lines upon a common end flap being along a line which is perpendicular to the path of movement of the bag tubes thereby forming an end flap bottom width line for each of said end flaps, characterized by a plurality of end flap press elements, conveyor means for moving in succession such plurality of press elements, the latter extending transversely of each of the oncoming end flaps of each oncoming bag tube, such press elements for acting on the two end flaps of a given tube end being spaced upon such conveyor means at a dimension substantially equal to the distance between opposite bottom width lines of a bag bottomer, a supporting surface for supporting one side of such tube ends during the pressing thereof by such press elements acting on the other side thereof, such press elements being constructed and arranged for pressing each end flap substantially at the two terminal points of the bottom fold score lines on such end flap.

5. In an automatic bag bottom forming apparatus, the combination comprising a bag tube conveyor, means for opening and spreading an end of each bag tube conveyed by said conveyor, such opening and spreading means forming upon each such spread bag tube end: two opposite side flaps and two opposite end flaps, such opening and spreading means thereby preliminarily forming the bag bottom and spreading the tube end with respect to a center line parallel to the direction of motion of the bag tubes as moved by said conveyor, such center line intersecting the forward and trailing end flaps at such end of the bag tube, at least aportion of each of said end flaps being substantially triangular in configuration by virtue of diagonal fold lines formed thereupon in response to said bag tube spreading, means for forming a pair of parallel bottom fold score lines upon each such spread tube end on opposite sides of said center line and parallel thereto, each bottom fold score line terminating at the opposite extremities thereof along the respective opposite diagonal fold lines situated on the same side of said center line, said parallel bottom fold score lines extending in the direction of motion of the bag tubes as moved by said bag tube conveyor, the leading extremities" of such a pair of said bottom fold score lines being positioned along a line which is perpendicular to the path of movement of the bag tubes and which defines therebetwecn the limits of a bottom width line, the same being true of the trailing extremities of such bag fold score lines, such bottom width lines thus being parallel, a plurality of end flap press elements, subsidiary con veyor means for mounting said elements in spaced relation thereon and for moving same in succession along the path of movement of such tube ends, such elements being at least two in number, the elements of each pair thereof being separated by a distance substantially equal to the dimension between the aforementioned parallel bottom width lines which extend transversely of the leading and trailing end flaps of a bag tube, such subsidiary conveyor means and said bag tube conveyor being operatively associated for movement at a common speed whereby each pair of such press elements can move at the same speed along with each bag tube end, tube end support means, each such press element being constructed and arranged for coacting with such support means for pressing each end fiap of each spread bag tube end in the immediate region of opposite terminal points of its respective bottom width line, and side flap fold means for acting upon the side flaps of a tube end for folding one side flap of the tube end over the other side flap thereof while said end flap press elements are pressing the opposite end flaps thereof.

6. In an automatic bag bottom forming apparatus, the combination comprising, a bag tube conveyor, mechanism for opening and spreading an end of each bag tube conveyed by said conveyor, such opening and spreading mechanism forming upon each such spread bag tube end side flaps and end flaps, said tube end opening and spreading mechanism thereby preliminarily forming the bag bottom and spreading the tube end with respect to a center line parallel to the direction of motion of the bag tubes as moved by said conveyor means, such center line intersecting the forward and trailing end flaps at such end of such bag tube end, means for forming a pair of parallel bottom fold score lines on opposite sides of said center line and parallel thereto, each bottom fold score line terminating at opposite ends thereof at and end flap, said parallel bottom fold score lines extending in the direction of motion of the bag tubes as moved by said bag tube conveyor, a plurality of end flap press elements, subsidiary conveyor means mounting said elements in spaced relation and for moving same in succession along the path of movement of such tube ends, such press elements being at least two in number, the elements of each pair thereof for acting on a tube end being separated by a distance substantially equal to the length of such bottom fold score line, such subsidiary conveyor means and said bag tube conveyor being operatively associated for movement at a common speed whereby said press elements can move along with each bag tube end, and tube end support means, such press elements being constructed and arranged for coacting with such support means for pressing each end flap of each spread bag tube end.

7. In an automatic bag bottom forming apparatus, the combination comprising: a bag tube conveyor including spaced gripping means for consecutively gripping each of a plurality of bag tubes along the leading edge thereof and moving same in succession sideways thereof relative to such apparatus in spaced relationship separated by a selected interval, mechanism for consequently spreading at least one end of such tubes moved by said conveyor and forming thereupon side and end flaps, such spreading and forming mechanism thereby forming a pair of bag bottom side flaps and a pair of bag bottom end flaps and also thereby forming diagonal fold lines upon each end flap, which fold lines are substantially equal in length, means for forming a pair of parallel bottom fold score lines on opposite sides of the center line of each spread bag tube end,

each bottom fold score line terminating at the opposite extremities thereof along the respective opposite diagonal fold lines situated on a common side of said center line, said parallel bottom fold score lines extending in the direction of motion of the bag tubes as moved by said bag tube conveyor, the leading extremities of each such pair of said bottom fold score lines as formed by said score line forming means being positioned along a line which is substantially perpendicular to the path of movement of the bag tubes and which defines a bottom width line, the same being true of the trailing extremities of each pair of such bottom fold score lines, such bottom width lines on a given tube end thus beingsubstant-ially parallel, a plurality of pairs of end flap press elements, subsidiary conveyor means for moving such elements in succession along the path of such tube ends as moved by said bag tube conveyor, corresponding of such elements of any two succcssive pairs thereof being separated by the aforementioned selected interval which is the same interval as that separating any two successive bag tubes moved by such bag tube conveyor, the press elements of each pair being separated by a distance substantially equal to the dimension between the aforementioned parallel bottom width lines which extend transversely of the leading and trailing end flaps of a given bag tube, such subsidiary conveyor means and said bag tube conveyor means being operatively associated for movement at a common speed whereby each pair of press elements can move along with a given bag tube end, a support situated adjacent said subsidiary conveyor means and such press elements for coacting with such elements whereby the latter can press each end flap of each bag tube end as it moves adjacent thereto, each press element having a pressing face which is conformed for pressing an end flap of the tube end in the region immediately adjacent opposite terminal points of the bottom width line of such end flap, and side flap folding means for acting upon such side flaps of a tube end during the aforementioned pressing action of such press elements for folding one side flap of the tube end over the other side flap thereby to bottom the tube end.

8. in an automatic bag bottom forming apparatus, a bag tube conveyor including spaced gripping means thereupon for consecutively gripping a plurality of bag tubes each on the leading edge thereof and pulling same in succession through said apparatus, said gripping means being spaced at a selected interval, mechanism for spreading a tube end of each of the tubes moved by said conveyor as the latter moves such bag tubes consecutively therepast, such mechanism forming a leadin g and a trailing end flap upon at least one end of each of such bag tubes, a plurality of end flap press elements, supplementary conveyor means for mounting said press elements in spaced relation thereupon and for conveying same in succssion in the same direction and at the same speed as said bag tube conveyor, such press elements being at least two in number and positioned for acting upon the two end flaps of each spread tube end, and means positioned along the path of said supplementary conveyor means for folding portions of each such spread tube end contemporaneous with the action of such press elements thereupon.

in an automatic bag bottom forming apparatus havin -"g tube conveyor for conveying a plurality of bag ti res in succession and in spaced relation relative to said apparatus, and also having mechanism for spreading at least one end of each bag tube as it is conveyed therepast, thereby forming thereupon two side flaps and two end flaps, ZUJQ also having means for forming two bottom fold more lines upon each such spread tube end, the combination therewith of means for applying a valve sleeve to an flap of each of said spread tube ends, a plurality of c d flap nrcss elements, supplementary conveyor means for mounting said press elements in spaced relation thereupon, such press elements being at least two in number and separated by an interval substantially equal to the 12 length of one of such bot-tom 'fold score lines, said supplementary conveyor means being positioned for conveying such press elements in the same direction as that of the aforementioned bag tube conveyor and along the path of the spread bag tube ends, such press elements and supplementary conveyor means being operatively associated with such bag tube conveyor for acting upon each pair of end flaps of each spread bag tube end as it moves along the path of such supplementary conveyor means, wherebyv each of such elements presses against its respective end the region of thettermini of such bottom fold score thereon, said sleeves so applied to said end flaps being in position by the press elements pressing therein an automatic bag bottom forming apparatus, the combination comprising a main bag tube conveyor; n ans for opening and spreading at least one end of each tube conveyed by said conveyor, such opening and spreading means forming upon each such spread bag tube cud: two opposite side flaps and two opposite end flaps, such opening and spreading means thereby preliminarily forming the bag bottom and spreading the tube end with respect to a center line parallel to the direction of motion of the bag tubes as moved by said main conveyor, at least a portion of each of said end flaps being substantially triangular in configuration by virtue of diagonal fold lines formed thereupon in response to such bag tube spreading; means for forming a pair of parallel bottom fold score lines upon each such spread tube end on opposite sides of said center line and substantially parallel thereto, each bottom fold score line terminating at the opposite extremities thereof along the respective opposite diagonal fold lines situated on the same side of said center line, said parallel bottom fold score lines extending in the direction of motion of the bag tubes as moved by said main bag tube conveyor, the leading extremities of each pair of such bottom fold score lines being positioned along a line which is substantially perpendicular to the path of movement of the bag tubes and which defines therebetween the limits a bottom Width line, the same being true of the trailing extremities of such bag fold score lines, such bottom width lines thus being substantially parallel; a plurality of end flap press elements; subsidiary conveyor means for mounting said elements in spaced relation thereon and for moving same in succession along the path of movement of such spread tube ends, such press elements being at least two in number, the elements of each pair thereof for acting upon a given spread tube end being separated by a distance substantially equal to the dimension between the afore mentioned parallel bottom width lines of such tube end; means for operative ly associating said subsidiary conveyor means and said main bag tube conveyor for movement at a common speed, each pair of said press elements moving along with a spread tube end; such subsidiary conveyor means comprising a first pair of endless bands situated in parallel spaced relationshipside-by-s-ide and along the path of the spread tube ends, there being a first group of such press elements secured to said first-named pair of endless bands for movement thereby, opposite extremities of each of such first group of press elements being secured to cor responding opposite locations of said first pair of endless bands, said subsidiary conveyor means also including a second pair of endless bands also situated in parallel spaced relation side-by-side but interposed between the aforementioned first pair of bands, there being a second group of such press elements secured each at the opposite extremities thereof to corresponding opposite locations of said second pair of bands, the interval separating the press elements mounted upon the first pair of bands being equal to the interval separating such elements mounted upon the second pair of bands; supporting means for said first pair of bands; supporting means for said second pair of :bands; the aforementioned operative means for operatively associating said main bag tube conveyor and subsidiary conveyor means including means for disengaging one of said pairs of endless bands therefrom where- 13 by the pair of bands so disengaged is shiftable thereby to adjust the interval between the press elements mounted thereupon and the corresponding press elements mounted upon the other pair of bands; tube end support means, each pair of such press elements for acting upon a tube end including one element mounted upon the first-mentioned pair of bands and the other element mounted upon the other pair of bands, such pair coacting with such support 14 means for pressing the two end flaps of each spread tube end at opposite terminal points of its respective bottom width line; and side flap fold means positioned for acting upon the side flaps of each tube end for folding same one over the other thereby forming such bag bottom contemporaneously with such pressing by the press elements.

No references cited.

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