US2641167A

US2641167A - Bag bottom forming device

Info

Publication number: US2641167A
Application number: US189271A
Authority: US
Inventors: Gramegna Franco
Original assignee: ST Regis Paper Co
Current assignee: ST Regis Paper Co
Priority date: 1950-10-09
Filing date: 1950-10-09
Publication date: 1953-06-09
Anticipated expiration: 1970-06-09

Description

10 shee s-shet 1 F. GRAMEGNAQ A 3 8 N l n R l e m m T a g m m N E A 18 4 G o w w 0 II M 0 mm NQY on g UUUOU MUMWHNE F fi. EOFQUTHEQ UDJU W j i m an, E Q0 mm M Ea Z w 5 a ll l 1. 4 P U V 0 H o x.

June 9, 1953 Filed Oct. 9. 1950 him-Liking 1M1.

ATTORNEYS.

10 Sheets-Sheet 2 5 INVENTOR. BYFQANCO GRAMEZGNA. w, chasm; 11-4.-

Arromvfrs.

June 9, 1953 F. GRAMEGNA BAG BOTTOM FORMING DEVICE Filed Oct. 9, 1950 moan PII ll l wllll June 9, 1953 F. GRAMEGNA BAG BOTTOM FORMING DEVICE l0 Sheets-Sheet 3 Filed Oct. 9, 1950 g M u.

G m R: MIQN Mm m N )T 1.0 m N A U m June 9, 1953 F. GRAMEGNA 2,641,167

BAG BOTTOM FORMING DEVICE 1O Sheets-Sheet 4 Filed 001;. 9, 1950 I 84 3 as L 80b 45 87 m 37a m '56b y a 88 86 56a. 6

INVENTOR. FRANCO GEA MEGNA ATTORNEYS.

June 9, 1953 F. GRAMEGNA 2,641,167

BAG BOTTOM FORMING DEVICE Filed 001;. 9, 1950 10 Sheets-Sheet s N INVENTOR.

FRANCO GRAMEGNA- BY ATTORNEY 5.

Jl me 9, 1953 F. GRAMEGNA I BAG BOTTOM FORMING DEVICE 1O Sheets-Sheet 6 Filed Oct. 9,- 1950 nunnnun v mm m5 WM T B @ov fimm i m m June 1953 F. GRAMEGNA BAG BOTTOM FORMING DEVICE 10 Sheets-Sheet 7 Filed 0st; 9. 1950 INVENTOR. FEA NCO GRAMEG NA. BY

1 ow a h M U June 9, 1953 F. GRAMEGNA BAG BOTTOM FORMING DEVICE 10 Sheets-Sheet 8 Filed' oat; e. 1950 A L N a m G M H W E 2 M v W m Q 1 1 k M, A N m 8v 8? I A R 8% B Nv mm: 00 i wuv I mag June 9, 1953 F. GRAMEGNA 2,641,167

BAG BOTTOM FORMING DEVICE Filed Oct. 9, 1950 10 Sheets-Sheet 9 L A===E j ,2 v Q 5 INVENTOR. FRA N.CO GEAMEGNA.

YUM, Lax, up;

ATTORNEYS.

June 9, 1953 F. GRAMEGNA 7 2,641,167

BAG BOTTOM FORMING DEVICE Filed Oct; 9, 1950 10 Sheets-Sheet 10 INVENTOR. A FRANCO GEAMQSNA. -Q5lv3 aka-L A T TORWEYS.

Patented June 9, 1953 UNITED STATES NT ()F FC'E.

BAG BOTTOM FORMING DEVICE.

Franco Gramegna, Milan, Italy, assignorto. Sit; RegissPaper Company, New York, N..Y., a conporationw oi New'York ApplicationOctolier 9, 1950,, Serial No. 189,271

11 Claims. l:

This invention relates to bag bottom forming apparatus, and more particularly to apparatus for automatically opening the extremities of bag tubes and thereafter forming side and corner flaps thereon preparatory to final forming of the bag bottom.

This invention includes improvements of. certain of the elements of the bag bottom forming apparatus disclosed in the copending United States patent application Serial No. 48,820, filed September 11, 1 948, for Bag Bottomer, by Edwin EL Burroughs (now Patent No. 2,576,047). Such new elements can be employed in a device now in use in. the United States of America.

Apparatus of this character suggested in. the past, for automatically opening the extremities of bag tubes and thereafter forming the side and corner flaps, have been quite successful with bag tubes formed of many' types of paper, such bag tubes including the multi-pl y and single ply varieties; However; such prior apparatus have not been entirely successful with bag tubes composed of certain other types of paper. Multiply bag tubes formed of ordinary kraft paper of the variety normally manufactured in the United States for bag use are relatively stiif due to the relative stiffness of such paper. That is, apparatus of this character suggested in the past has proven quite satisfactory for the stiiier types of kraft papers but has not fulfilled all desired results with respect to the less stiff varieties.

One of the objects of the present invention is to overcome the above difliculties or to reduce same to insignincance.

The invention, in one aspect thereof, comprises mechanism for use with an automatic bag bottom forming apparatus, the latter having a bag tube conveyor including spaced gripping means for consecutively gripping a plurality of bag tubes near opposite extremities thereof and moving same in succession relative to the apparatus in preselected spaced relationship along a common path, the improved elements including improved tube end opening means and tube end spreading means.

The novel tube end opening means comprises a pair of endless belts, each being mounted upon a pair of wheel members and each having a like plurality of suction cups mounted in spaced relation thereon, such cups coacting to open the end of the bag tubes. The endless belts can be in the form of, for example, sprocket chains and are positioned side-by-side in substantially the same plane whereby a side run of one belt is adjacent a side run of the other belt. The end- 2: less belts and the cups thereon are movable in synchron-ism whereby opposed pairs of cups are movable in phase with oneanother, each such pair including one cup on each belt. The opening of a tube end is effected by first permitting the suction cups to gain a grasp upon opposite sides of a tube end through the intermediary of vacuum created therein and thereafter separating the cups. Each pair of suction cups, of course, moves with its respective bag tube during a substantial portion of its travel alongthe above-mentioned common path and during such portion of the travel of the cups are able to gain an adequate grip upon the tube ends; The separation of a pair of the suction cups is effected preferably by cam means, the suction cups being pivotally mounted upon their respective belts in such a manner that their relative angular relationship is under the influence of such cam while the pair of cups is moved linearly in the direction of the tube ends or inthe direction of the bag tube conveyor. By means of such cam, the angular relation of a pair of suction cups can be changed from a closed position progressi'vely" to an open one whereby a tube end grasped thereby is thus opened to a desired extent and simultaneously said cups and tube end are undergoing linear or translational movement in the direction of" the motion of the bag tube conveyor.

The novel tube end spreading means (as opposed to the tube end opener) is also referred to as a bag bottom flap-forming device and comprises a plurality of spreader units which are movable in a novel manner upon a conveyor which maintains each spreaderuni't in a constant attitude relative to the path of movement of the bag tube, that is, a longitudinal axis of each unit is maintained in a common attitude relative to the path of movement of the bag tubes, for example, vertical to the plane over which the bag tubes move. The means for so controlling the movement of the several spreader units causes each unit to be lowered into an open tube end shortly after the opening action of said suction cups, whereby such lowering of the unit has a pressing or ironing action upon the tube end so opened. After such lowering of a spreader unit the latter is moved along with the moving tube end in linear or translational movement and novel flap-forming or flap-folding mechanism is actuated to-form the leading and trailing corner flaps and coincidentally the. side flaps of the bag bottom. For this purpose each spreader unit is provided witha pair of spreader tongues which can be retracted or extended relative to the of the spreader tongues constituting substantially the entire lengths thereof. Thus each spreader unit includes a pair of flexible tongue members retractilely mounted in guides formed therein with the outer ends thereof. directed in opposite directions. Each outer end of a tongue is provided with a V-shaped corner flap-shaping member secured thereto. Suitable means are provided for synchronously extending and retracting the pairs of tongue members in preselected relationship with the movement of the bag tube conveyor whereby a spreader unit, as above mentioned, may be lowered into each oncoming opened tube end and can be moved along therewith at the same speed thereof and the corner and side fiaps positively formed therein by said tongue members. Thereafter adhesive is applied to the flaps and the bag bottom is formed by folding the flaps as will appear below.

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 in vention. The invention consists in such novel combinations of features and method steps as may be shown and described in connection with the apparatus herein disclosed.

In the drawings:-

Figs. 1 and 1a are respectively the first and second halvesof an automatic bag bottom forming apparatus which is analogous to that disclosed in copending application Serial No. 48,820,

filed September 11, 1948, by Edwin E. Burroughs .(now Patent No. 2,570,047) with the exception that the tube end opener and tube end spreader means embody improvements which acting alone and in combination with the other elements comprise the present invention;-

Fig. 2a to Fig. 2 inclusive, illustrate the successive steps in the formation of a pasted bag bottom by means of the present invention;

Fig. 3 is a side elevation of the novel tube end opening means employed in the present invention;

Fig. 4 is a detailed transverse view of a pair of suction cups employed on the tube opening device shown in Fig. 3, such cups being in a closed position;

Fig. 5 is a transverse view of such suction cups shown in Fig. 4 but in a spread condition, said figure also illustrating the immediately adjacent means for mounting the suction cups;

Fig. 6 is a view partly in section and with parts broken away of the tube end opening apparatus taken substantially on line 6-6 also of Fig. 3;

Fig. 7 is a sectional view taken substantially on line 1-1 of Fig. 3.

Fig. 8 is a side elevation of one half portion of the conveyor means for moving the tube end spreader units, that is, it illustrates one of the pairs of endless chain devices which are employed in such conveyor means;

Fig. 9 illustrates the other half of such tube end spreader unit conveyor means and illustrates the position of a plurality of individual spreader units which are mounted thereupon;

Fig. 10 is a side elevation, partly in section and with parts broken away, showing on an enlarged scale one of the tube end spreader units illustrated in Fig. 9 and also showing in detail portions of the means for mounting such unit upon its conveyor means and the operative association of such spreader unit with control means therefor;

Fig. 11 is an end view of the tube end spreader unit shown in Fig. 10;

Fig. 12 is a fragmentary detailed view of a portion of a flexible spreader plate employed in the tube end spreader unit;

Fig. 13 is a plan view of a tube end spreader unit, such as that shown in Fig. 10 but with parts thereof in a different operative position and also showing the manner of associating such tube end spreader unit with conveyor means therefor;

Fig. 14 is a side elevation of the tube end spreader unit shown in Fig. 13 with the spreader tongues thereof retracted into the frame-of the unit; Fig. 15 is a perspective schematic view of th conveyor means for the spreader units; and

Fig. 16 is a view of an opened and spread bag tube and illustrative of the several parts thereof.

The form of the invention illustrated in the accompanying drawings, by way of example, comprises apparatus for operating upon the ends of a previously formed bag tube, or a succession of such tubes, preferably of the multi-wall stepped end variety, whereby automatically the bag tube end is opened and thereafter corner and end flaps are formed thereon and the tube end is prepared to be closed and sealed, with the exception of the bag valve. Of course, if desired, one or both ends of a bag tube can be formed into a bottom with or without a valve.

Referring to the drawings in greater detail, the novel elements described herein are designed for use with a continuously driven bag tube conveyor. The present invention employs in combination with the above-mentioned elements for acting upon the tube ends, a master bag tube conveying means having a plurality of equally spaced bag tube gripping devices thereon by which the bag tubes may be successively grasped and continuously advanced to the various operating stations at a uniform but adjustable speed. As shown in Fig. 2, a pair of such gripping devices is shown at 2|, 22 which are designed for grasping the leading edge of a bag tube and urging it in the direction of the arrow 23 to such-various operating stations. A common power source is employed for driving not only the bag tube conveyor means but also all of the various units which. act upon the bag tube and in particular the improved elements to be set forth herebelow. Suitable means are provided, however, for altering the phase adjustments of the novel elements for opening the tube ends and spreading same, together with certain of the other units, whereby they can be adjusted as desired while the apparatus is in operation. 1

The bag tube grippers 2i and 22 (Fig. 2a) are mounted upon a pair of synchronously driven endless sprocket chains or belts and are adapted successively to grasp, together with numerous other similar pairs of grippers, bag tubes and to pull same through the machine. The bag tube grippers act in pairs, one gripper of each pair cups around the path of movement thereof,

which, of course, constitutes the movement of their

respective conveyor chains

35 and 36.

Each pair of suction cups as at 33, 34 (Figs.

4 and thus is subjected to the following movements after it grasps a. tube end (Fig. 4): (a) linear -or translational movement from left to right, as viewed in Fig. 7, in the direction of motion of the bag tube; (b) angular movement about the respective pivots 5D and 5| wherein each suction cup is tilted upwardly from the position shown in Fig. 4 to that shown in Fig. 5;

(c) movement away from one another, that is, movement transverse to the direction of movement of the bag tube whereby the cups are spread apart and are moved from the position close to one another, as shown in Fig. 4, to the spread apart and tilted position shown in Fig. 5; (d) a lowering movement, that is, the suction cups are lowered relative to the plane of the main body of the bag from the elevated position shown in Fig. 4 to the depressed position shown in Fig. 5, such movement being attributed to the tilting of the

endless chains

35 and 36 in a downward direction, as shown in Fig. 3, that is, with the -downstream extremity of the chain lower than the upstream, such tilting being in the direction of motion of the bag tubes.

The tilting or angular movement of the

suction cups

33, 34, about the

pivots

56, 5| is controlled by a cam action through the intermediary of a cam follower roller for each cup which coacts with a guide or cam member. As shown in Figs.

3-5, inclusive, it will be seen that the

suction cups

33, 34 have operatively associated therewith the

rollers

59 and 60, respectively, which in turn ride upon the guides or cams 6|, 62, respectively.

Referring to Fig. 3, the guide or cam 62 is well illustrated showing an inclination thereof .relative to the plane of the endless chain 36, ,which inclination effects the angular movement of the suction cup 34 about the pivot 5|, it being understood, of course, that the guide 6| is similarly disposed relative to the sprocket chain 35. The guides 6| and 62 may extend underneath their

respective chains

35 and 36 throughout the lengths of such chains, if desired, wherein the rollers 59 and 68 are at all times resting upon their respective guides. However, if desired, the

cams or guides may be provided only for a portion of the length of their respective chains, namely, beneath the so-called inner runs thereof. For example, the guide 6| may extend to the point 61a (Fig. 7) in a counterclockwise direction beneath the chain 35 and thence to the right in a downstream direction to the point 6 lb, and similarly the guide 62 may extend from an analogous point 62a in a clockwise direction around a portion of the pinion 39 and thence beneath the chain 36 to a point 621). However, as shown in Fig. 6, the guides 6| and 62 are coextensive with their respective chains, that is, they extent therebeneath throughout the length thereof.

In the form of the invention shown, with particular reference to Figs. 3-7, inclusive, each end- .less chain has secured thereto only two suction cups and each of these cups is synchronized in motion with a corresponding cup on the opposite endless chain or conveyor s0 that a pair of suction cups is brought into the relationship shown as at 33, 34 (Fig. 4) the axes of which are in alignment, such suction cups being referred to as opposed suction cups. The lengths of the

chains

35, 36 are so selected that the distance between the axes device. .18 which communicates torque to an annular of the

sprocket wheels

31, 38 and 38, 46 requires only that two suction cups be aflixed to each such chain. However, if the latter chains were longer, additional suction cups could be employed.

As shown in Fig. 7, when one pair of suction cups has opened and released a bag tube end, the second pair of suction cups will be in position for shortly grasping the next oncoming bag tube end.

Referring now to Figs. 1 and 6, the mechanism for communicating torque to the

shafts

43, 44 and to said suction sleeves, together with certain of their related parts, will now be described. A common driving means, such as an electric motor (not shown) provides a torque for driving the entire apparatus and such motor may be operatively connected to a main power shaft 63 (Fig. 1) which extends substantially the full length of the apparatus and is rotatably mounted upon one side of the frame 24 by means of suitable brackets, as at 64. Extending across the path of the bag tubes transversely thereto is a so-called transverse power shaft 65 which is best shown in Fig. 6. This shaft is drivably connected to the

endless chains

35, 36 and to the suction sleeves, as will appear more fully herebelow. Torque from the main power shaft 63 is communicated to the transversely extending shaft 65 through the intermediary of a gear train as follows: a gear 66 upon the shaft 63 meshes with a gear 61 upon an intermediate shaft 68, the latter through suitable miter gears located within a housing. communicates torque to a vertical shaft 10 which is operatively connected to said shaft 65 also through miter gears located within a housing H.

In order to provide manually operable means for adjusting the phase relationship of the suction cups with the bag

tube conveyor chains

25, 26 and hence with the bag tubes which are conveyed thereby, a manually adjustable differential 12 is interposed in the shaft 68, said differential having an adjustment knob as at I3, adjustment of which will effect desired phase adjustments of said suction cups with the oncoming bag tubes. It is understood, of course, that the suction cups upon both of the chains move in fixed phase relationship to one another by virtue of the geared interconnection between the driving means for the

conveyor chains

35, 36 as will now be described.

Referring to Fig. 6, torque is communicated to shaft 44 which drives the conveyor chain 36 and to the shaft 43 which drives the chain 35 by means of miter gears 14 and 15 mounted respec tively upon the shaft 65 and a shaft 16, the latter being mounted for rotation in suitable bearings upon a frame portion 11 of the tube end opener Rigidly secured to the shaft 16 is a gear gear 19 which embraces and is rigidly secured to said suction sleeve 56. The latter is rotatably mounted upon a stationary tubular support which in turn is secured rigidly to said frame portion 11, the shaft 44 being rotatably mounted within a passage 80a formed in the tubular support 86. The suction sleeve 56 is held against downward axial movement by means of an annular or ring retainer 8| which threadedly engages the support member 80 beneath the sleeve 56.

Rigidly secured to the upper extremity of the shaft 44 is a gear 82 which meshes with a gear 83 which in turn is rigidly secured beneath the miter gear 15 and which rotates therewith. Torque is communicated to the shaft 43 by means of gears 84 and 85 which are respectively analogous'to gears 83 and 8;, the gear 85 being.

keyed to the shaft 43.

A rotatable suction sleeve 36 (analogous to sleeve 56) is provided for aiding in communicating a vacuum to the suction cups upon the chain 35 and torque is communicated to suction sleeve 85 by means of an annular gear 37 which embraces same and which meshes with an idler gear 81a which in turn engages the gear 18,

The suction sleeves and 86 are driven in the same direction .fls the shafts 4.4 and 43, respectively, whereby the hoses which intercom nect said sleeves with their respective suction cups are shifted around with the cups and do not become twisted or wound about the tabular support members as at Elli. The shaft 43 is rotatably supported in a tubular support member 88 which is analogous to member 83 and is provided with a central passage 88a.

The

hoses

55 and 55a interconnect the I'Qtat? able suction sleeve 56 with the

suction cups

34, 34a (Fig. 6), and the hoses 54, M. interconnect sleeve 85 With

suction cups

33 and 33a.

Suction or vacuum is communicated to the

hoses

54, 54a and 55, 55a as follows: The

above suction sleeves

55 and 85 rotate about their respective tubular support members ,8!) and $8. The latter are provided with a plurality of pase sages in the cylindrical surface thereof, which passages periodically come into register with passa es ass 55 and 55b f the hos 55 n 55a.

Analo ous structure is, of course, provided for the suction 01 1 5 133, 33g. with respect to the suction sleeve 86 and the tubular support member 88. As is best also shown in Fig. 6, a suction passage 8% is provided in the tubular support 80 which communicates With the above-mentioned orifices which are movable into register with said

passages

56a and 56?). Such an orifice is shown as at 80c.

Analogous suction passages and orifices are provided at 81; and 880 for the suction sleeve 86 (Fig.6).

Tu e and spreader me ns..-The tube eno preadi g means g nerally are d vided in is a group of tube end spreader units, one of which ni s is shown as (Fig. 9) and (b) conveyor means for tube end spreader units, such means being indicated generally at all in Figs. 1, 8, 9 and i5. The tube end spreader units are also referred to as baa bottom flap forming ele: ments and as will appear below are constructed and arranged. for folding the open bag tube ends in such a manner positively to form the corner and side flaps for the bag bottom.

Regarding the conveyor means for the tube end spreader unit s, reference is made to Figs. 8,9 and 15, particularly the latter, wherein there are shown means for movin such tube end spreader units upon an endless conveyor in such a man-ner that a vertical axis 9! of a spreader unit as at is maintained continuousl in a vertical relationship to the main body portions of the bag 28 (Fig. 2c) as they are moved through the apparatus. Thus said axis 9! is maintained continuously in a vertical relationship to the score line 3b. If the latter is omitted and the tube ends are not bent in the manner shown in Fig. 20, said axis 91 is maintained in a constant attitude relative to the bag.

Such conveyor means are constituted by a pair of endless conveyors, as at 92 and 83, said conveyors being of the belt variety and preferably comprising sprocket chains which pass reiii spectively over pairs of pinions or sprocket wheels M, and 96, 91 as is best shown in Fig. 15. The corresponding wheels of each pair thereof are parallel and positioned substantially side by side in an overlapping but spaced relationship with the axes thereof parallel but spaced apart by a preselected distance preferably in a common horizontal plane. For example, corresponding wheels it and 95 are parallel with the axes fi 'ia and thereof, respec'ti ai being parallel but spaced apart a preselected distance indicated at i-ili a common plane which in the present i .nce happens to be horizontal.

The one conveyors 92 and 53 are driven at a common speed by suitable means to be set forth hereinafter.

The corresponding

sprocket wheels

95 and 91 are situated relative to one another in a manner analogous to that of wheels M and Q6. The

axial distances between Ihe pairs of wheels M, 95

and 9G, are the same.

For purposes of calrity, only a portion of a tube end spreader frame, as at 855a (Fig. 15) is shown in order to illustrate the manner of mounting the tube end spreader unit upon the two conveyors E512, ili. The frame portion 83a is rectangular and provided with rollers 99, liiil and till, iilzl located respectively one at each corner thereof. Rollers 951, Nib rest upon a track Hi3 (Fig. lb) and rollers ltil, Elli? upon a track I84. It will be explained in connection with Figs. i0 and 11 that the said rollers in fact are moved in grooves over a substantial portion of their orbits whereby each roller is engaged by a rail at diametrically opposite sides thereof. However, for purposes of clarity single rails as #63, it"? will be described in connection with Fig.15.

"ihe tube end spreader frame portion 83a is secured to :the chains 92 and seat diagonallyopposed locations, namely, at its and Live, said locations being separated by a distance, meas ured along conveyors, equal to said prel s ist n 98. s h dis ance being moi: ed 3 .3 '5

It will be seen that when the conveyorbelts or

chains

92, 93 are moved in a counterclockwise direction, as indicated by thearrow 88, said frame member 890; will be shifted such that the juncture points 95 and lot wiil be angularly shifted about the wheels 84 and at) simultane-- ously and at the same angular speed. Due to the spacing of the wheel axe by the distance 98, thhe axis ti will remain constant in attitude, for example, vertical, as the spreader unit is lowered. In order to steady said frame 89a. as it so descends. a guide member we is provided for engaging the roller Ill 4.

Thus the rollers [Eli and till do not follow and move alongside of their

respective chains

92 and 93 during the downward angular movement.

When spreader unit 89 nears the righthand extremity of its orbit in the neighborhood of the

wheels

95, 97, the upward angular movemerit-thereof onto the upper runs of the chains is assisted and steadied by a guide ill] comprising a rail member for engaging the roller Hit in a manner analogous to the coaction of the roller if and the guide N19.

The movement of the tube end spreader units mounted upon the

conveyors

92, 93 is, of course, synchronized with the movement of the

conveyor chains

25, 25 whereby a spreader unit is lowered into each opened tube end, as shown in Fig. 2c. The phase relation of the spreader units and the

conveyor chains

25, 26 can be adjusted by a hand adjustable difierential in the torque power line for the

pinions

94, 96 and 95, 91. Such torque transmission line includes shafts 63a (Figs. 1 and 2) and 63b which are powered by shaft 63. Interposed in the former is the abovementioned differential as at 630 having a knob at 6301.

It has been found desirable to select the length of

conveyors

92, 93 to accommodate seven tube end spreader units 89, it being possible to produce accurately a heretofore unattained number of folded bag bottoms per minute with this number of spreader units.

The distance between the axes of, for example,

Wheels

95 and 91 has been selected in order to permit each tube end spreader to perform its function with sufficient time so that there will be no undue haste in the operation thereof. That is, the distance between such axes should be sufficient to allow time enough for each tube end spreader to act without any injurious shocks to the bag tubes and to the machine when the rate of motion of the bag tube conveyor is high.

For purposes of clarity as above mentioned the rail means for guiding the tube end spreader units 89 are not fully illustrated in Fig. 15. For such full illustration reference is made to Figs. 8-11,- inclusive, with particular reference to Figs. 9 and 11. In Fig 11 it is seen that the rollers 99-I02, inclusive (99 and IOI of which are shown), move within the tracks I03 and I04, that is, the rollers 99, I move in the tracks I03 and IOI, I02 in the track I04. These tracks are of the so-called grooved variety wherein the distance between the tracks, for example, the distance between portion I03a and I031) (Fig. 11) (or between W411 and I04b) is slightly in excess of the outer diameter of the roller 99 whereby a close control is maintained over the direction of said roller and the tube end spreader unit is prevented from wobbling or angularly shifting while moving along the lower runs of the

conveyors

92, 93. The same is true of the rail structure along the upper runs of said conveyors or chains.

The

chains

92 and 93 preferably move between flanges I030, I03d and I040, I04d as is best shown in Fig. 11. These flanges are equal in length to that of the guide rails I03 and I04.

The upper and lower portions of the tracks I03 and I04 are approximately of equal length, such length being about equal to the distance between the centers of their

respective wheels

94,95 and 96, 91. I

The guide members I09 and III] for steadying the spreader units during their lowering and raising are provided with suitable entrances and exits to facilitate the movement of aroller as at IOI into guide I09, and roller IOI into the guide IIO.

A conveyor frame generally indicated as at I I I (Fig. 8) is provided upon which the shafts or journals are mounted for the

conveyor wheels

94, 95 and 96, 91. It is desirable to provide means for controlling the tension upon the conveyor belts or

chains

92, 93 by adjusting the axial distances between the

wheels

94, 96 and'95, 91. The means for accomplishing this are shown in Fig. 8 and constitute a movable mounting for the

wheels

94, 96, such mounting being adjustable and generally indicate at H2. The latter comprises a pedestal II3 for supporting a wheel bracket II4 which is'somewhat in the shape of 12 an inverted L having a face as at H411 which rests upon a supporting face II3a of the pedestal II3. By means of threaded adjustment bolts H5, H6 it is possible to shift the bracket H4 and hence

wheels

94, 96 to the left or to the right, as viewed in Fig. 8.

Tube end. spreader unit.-As has been mentioned above, there are preferably several tube end spreader units employed in the tube end spreader means. They are mounted at equally spaced intervals upon the

conveyors

92, 93 in the manner described above concerning Figs. 9 and Referring to Figs. 10-14, a tube end spreaderunit (or side and corner flap folding or forming unit) is constituted by a pair of spacer mem'-' bers H1 and H8 (Fig. 13). Spacer member II1-, as viewed in Fig. 14, consists of a main vertical support Illa having rigidly secured thereto and preferably integral therewith adjustment arms H9 and I20 which are coaxial and which extend perpendicularly in opposite directions from thevertical support II1a near the upper portion thereof. Below the arms H9 and I20 are outwardly extending arms I2I and I22 which also extend coaxially and perpendicularly to the vertical portion II1a in opposite directions and dif-" spreader plate guide members I26 and I21. The

latter are generally U-shaped, for a purpose to appear later, as is well shown in connection with member I26 (Fig. 11). Referring to Fig. 13, it

will be seen that the plate guide member I26 is provided with bores for receiving the armsI I0 and I23, such bores being indicated as at I26a and I26b. Furthermore, the plate guide mem-- ber I26 is provided with grooved arms as at I28 and I29 for engaging the spacer arms I2I and I25 as is well shown in Fig. 11.

By means of the above-described spacer mechanism for the tube end spreader unit, it will be seen that the plate guide members I26 and I21 may be adjusted in their spaced relationship from the position shown in Fig. 10 wherein they are closely adjacent one another, to the widely separated position shown in Fig. 14. The reason for providing for such adjustment is to increase the so-called "universality of the apparatus with respect to the size of bag widths which the machine can accommodate, that is, to provide for a wide variety of sizes of bag widths upon which there can successfully be formed the side and corner flaps above mentioned in connection with Fig. 2.

Referring to Fig. 16, the term bag width refers to the dimension I30 measured between the outer peaks of the corner flaps indicated as at I3I and I32. The term bottom width refers to the dimension I33 which is measured between the bottom fold lines indicated at I34 and I35.

The plate guide members I26 and I21 are provided with slotted guide portions indicated at I36 and I31, respectively, in which there are movable vertically spreader plates I38 and I39 which are retractile relative to such guide members as will now appear.

and 139 are urged by means of suitable guides to move in opposite directions. that is, the outer extremities thereof I38 and I39a are guided to move in opposite directions. Such uiding means for the spreader plate I138 are well shown in Fig. 14 consisting of a roller I40 and a curved uide It]. An analogous roller and curved uide for the spreader plate I39 are shown at I42 and I43, respectively.

By simultaneously urging downwardly the upper extremities 13812, 13% :ot the spreader plates I38 :and I39 it will be seen that .said plates will be extended outwardly to the position shown in Fits 13.

The mechanism for communicating upward downward movement to said plate extremities I381), I392) is best shown in Figs. 9-14, inclusive, and .is constituted by an adjustable cam indicated generally at I44 (Fig. .9) which is in the shape of a vflat V and which cooperates with a follower I45 (Fig. '10) which in turn is connected to .a :wrist pin I45, the latter being secured by resilient means to the upper extremities I38?) and I391) of said spreader plates. The cam follower :or roller I45 is mounted upon an .arm 14'! which in turn is secured rigidly to said wrist pin I46. In order to guide the vertical movement of ascent and descent of the'wrist pin I46 and its connected cam follower I45, 2, suitable guide carriage is provided as at 148 (Figs. '10 and 13) which preferably is rectangular in shape and has mounted at each of the :corners thereof rollers I49. Such rollers consist .of groups of two on each side of the carriage I48 and each such group moves in a vertical guideway I511. The carriage 1 48, of course, is also rigidly secured to the wrist pin I46 and the vertical oscillating of such pin is thus made steady without wobble. The axis of the pin 146 is thus maintained in a horizontal plane, as viewed in Fig. 14.

addition to the four rollers I 49 "which are secured to the corners of the rectangular carriage I48, the guide means for the wrist =pi-n I45 includes 'a pair of rollers -I49a, one secured to each vertical side of the carriage, as is best illustra'ted in Fl-g. '13. These rollers are movable upon plates l tfla and the axes thereof are iper- Dendicular to-tho'se of rollers I 49.

The extent of the vertical movement of the guide carriage I48 and, 'of course, the follower I45 is controlled by the angle at which the arms of the V-s'haped cam 1-44 are disposed relative to their vertical axis. As is shown in Fig. 9, the cam 144 is constituted "by a left arm I I-4a, a right arm I44?) and a center section I440. The latter section may be raised and lowered by any suitable mechanism, one form of which will be de-' center section ;I44.c by means of a worm andwheel :device indicated generally at I52 :(Fig. 59 This latter mechanism includes :a vertical threaded shaft I53 which :is embraced by anania-ll-y stationary sleeve 1.541120 which is secured a worm wheel I55 which is under the .mfluence ore. worm 1.56, the, latter ha i :a shaft which is shown as at I51 (Fig. .8) and constitutes the shaft of the handwheel I5;I.

It is desirable to Provide a cushioning means for resiliently transmitting the downward thrust of the wrist pin 146 to the flexible plates I38 and I39. Such cushioning means for plate I33 are shown generally at I58 (Fig. 11,) and are con.- stit-uted by, for example. a cushioning spring I59 which. s viewed in Fig. .ll, thrusts upwardly against a wrist pin journal member I60, the latter being sl-idably mounted within a slotted guide I6I. Normally the spring I59 urges the journal member I60 against an up er limit-stop of the guide .IBI. There, of course, is a similar cushioning device for the opposite extremity of the wrist pin I46,.i. e., for plate I39.

By virtue of this cushioning device, the possibility of tearing the bag tube ends is substantially reduced and a yielding or resilient thrust.

is provided which urges the spreader plates I38 and 139 in opposite direction outwardly as viewed inFig. 13,.

The outer extremities 138a, I39a of the plates I38 and I39 have secured thereto respectively corner flap shapers I,38c I390 (Fig. 13') respectively. These .shapers are also referred to as corner flap mandrels. erably constituted by two portions which are separated by that is, a portion as at 1334: is situated 45 relative to a central axis of the spreader plate I38 and the other portion I38,c'-' is similarly situated on the opposite side of such axis.

Further in connection with the extent of -.-sepa-' ration of the guide members I26 and I2! (Fig- 14 it is, of course, understood that these members can be secured in any desired separated position within the limits of the arms H9, I20 and such adjustments must be made while the ap paratus is stationary.

Thus the extent of theseparation of the points of the corner flap shaper members [38c and I390 can be adjusted by Ia) moving the gide members I25 and I21 to desired positions upon the arms I19, I20 and I23, I211; and .(blbyadjusting the handwheel I5! which controls the angularity of the arms I44a, I442: of the cam I44. The latter adjustment is normally for fine adjustments and can be made while the mach-inc is running.

.Such'fine adjustments, for example, may .be-of one-eighth inch or one-quarter inch in the ex.- tent of separation of said spreader "points. For any larger adjustments it has been found desirable practice to eiiect same while the apparatus is stationary by adjusting the separation of the guide members I26, .I 2.1.

. The guide members I26, I21 are generally .U-

shapedas is best shown in Fig. 11 for member I26 because such conformation accommodates the verticaloscillatory movement of the wrist pi-n I46.

In operation, a succession of bag tubes are grasped by the grippers :2I and M and moved :by means of the conveyors 2.5, 2.6 through the apparatus, the :slits 29 and score lines 30 being formed as above mentioned (Figs. 2a and 212'). There.- aiter-the bag tube ends 280, and 28b .are bent at right angles to the main body of the bag, as shown in Fig. 2c, and suction cups grasp each of the tube ends for opening same. For example, as shown in Fig. 20 a pair .33, 13A grasps the tube end 2% andgradually opens same as itprogresses along the path of the tube end, as explained in connection with Figs. 3, 4 and 5. A tube end spreader .unit is thereafter lowered (Fig, 29,) into Such shapers are pref each of the open tube ends, such loweringoccur ring with the axis 9| thereof perpendicular to the main body of the-bag tube. Each tube end spreader unit accomplishes an initial flattening and spreading of the open tube end by virtue of such lowering and under the action of the spreader plate control mechanism, including the V-shaped cam I44, and its follower-mechanism, the points of the spreader plates are gradually separated to a desired and-finely adjustable extent, as best shown in Fig. 2 f, whereupon the bag tube corner portions are positively and forcefully caused to fold over the corner fla shaping members I380 and l39c, forming the corner flaps l3l and I32 and forming positive diagonal-fold lines l3ia, l3lb and 132a, i321). Also side flaps 28a and 28b are positively spread out as a result of the positive folding of the corner flaps over their respective shaping members. The points of the spreader tongues or plates are thereafter re-- tracted from the position shown in Figs. 2 and 13 to that shown in Fig. 14 also under the action of the cam M4 whereupon-the bag tube is in the condition shown in Fig. 2g.

'Thereaftersaid tube is acted upon by mechanism to complete the forming of the bag bottom as disclosed in the above-mentioned copending application Serial No. 48,820, filed September 11, 1948, by Edwin E. Burroughs (now Patent No. 2,570,047). That is, the tube ends are pressed as bypressing rollers'indicated generally at I62 and thereafter the bottom fold or score lines are formed as at I63 (Fig. 29) by a scoring device I64. Paste is then applied, as shown in Figs. 271. and 21', by a suitable gluing device I935, a sleeve inserted by sleeving means I66 and thereafter the side flaps are folded over and pressed to complete the forming of the bag bottom as shown in Fig. 2a.

There is thus provided a novel apparatus for acting upon bag tube ends for forming bag bottoms wherein the tube ends are positively opened by suction means which are capable of moving with the bag tube ends for a sufficient time to allow the suction cups thereof to obtain a positive grasp thereupon whereby there is no failure in thepulling open of the tube ends because this structure is so constructed and arranged that the spreading of the suction cups does not occur until suflficient time is allowed to obtain such a'positive grasp The tube end spreader means are capable of" accommodating with great accuracy a Wide variety of bag widths and'forming side and corner flaps in a positive andrapid manner without shock or damage to the tube means and in such a manner that the diagonal fold line of the corner flaps are formed with great precision whereby the percentage of defective bag bottoms formed is substantially eliminated. Furthermore, While the machine is in operation, fine adjustments in the separation of the spreader points can be made which permits of an increased output by reducing the time when the apparatus is shut down for adjustment.

While-the invention has been described with respect to a certain preferred example which has givensatisfactory results it will be understood by those skilled in the art, after understanding the invention, that various changes and modifications may be made without departing from the spirit and scope of the invention, and it is intended, therefore, in the appended claims to cover all such changes and modifications.

What is claimed is: v i

1. In apparatus for forming the ends of bag 16 tubes, the combination comprising: -a' conveyor for moving such tubes; at pair'of suction cups;- means for moving said cups linearly along the path of movement of such bag tubes; means for mounting said cups for pivotal movement relative to one another, means for pivotally movingsaid cups from a closed-opposed position with the mouths thereof adjacent one another to an open position with such mouths separated, said cups, moving and mounting means being positioned and controlled for grasping the opposite sides of a closed end of a bag tube and opening same, said means for so linearly moving said cups being operable simultaneously with said means for so pivotally moving said cups; a flap folding device for acting upon an open tube end comprising a frame member, a pair of tongue guide members adjustably secured to said framemembers, a pair of flexible tongues mounted for sliding movement in said guide members, the latter directing the outer extremities of each of said tongue members in opposite directions, means for slidably moving said tongues simultaneously relative to said guide members whereby such tongues can be. extended or retracted, each of said tongues having a substantially V-shaped forming element secured to its outer extremity; and means for moving said flap ,folding devicein timed relation to said conveyor and to a bag tube moved thereby, such moving means being constructed and arranged for inserting said folding device into the end of a bag tube whichhas been opened by said suction cup means and for actuating said tongues positively to form corner andside flaps upon the tubeend. 1

2. A bag bottom flap forming element including a frame member, a pair of guide members mounted in parallel relationship upon said frame member, the latter being constructed and arranged for permitting adjustment of the spaced relationship of said guide members, a pair of flexible plate members comprising tongues each being mounted in one of said guide members and adapted for sliding movement therein, said tongues having inner and outer extremities, the outer extermities thereof being directed in opposite directions by said guide members, and means for operatively interconnecting such inner tongue extremities whereby said tongues can be synchronously retogether for gripping opposite faces of a bag tube end during the initialportion of such linear move-' ment, said cam means being constructed'and arranged gradually to spread said cups apart progressively with such linear movement until the tube end is opened; bag bottom flap forming means comprising a frame member having therein retractilely mounted a pair of nap spreader tongues the'outer extremities of which are di rected in oppositedirections; means for moving said flap forming means into the end of a bag tube opened by 'saidsuction cups, said means also moving such means linearly along said path; and means" for extending and retracting said tongues 17 in timed relation with the movement of said canveyor.

4. In an automatic bag bottom forming apparatus, a bag tube conveyor including spaced gripping means for consecutively gripping a plurality of bag tubes near opposite extremities along the leading edge of each tube and moving same in succession relative to said apparatus in preselected spaced relationship along a common path; tube end opening means including a pair of endless belts, each having a like plurality of suction cups mounted thereon in spaced relation, said belts being positioned side by side and in substantially the same plane, whereby a side-run of one belt is adjacent a side-run of the other belt, said belts and cups thereon being movable in synchronism whereby opposed pairs of cups are movable in phase with one another, each such pair including one cup on each belt, means for mounting each of said cups for pivotal movement relative to its belt, and cam means for controlling the angular relation of the cups of each opposed pair thereof whereby each such pair is moved from a closed position progressively to an open one While undergoing linear movement in the direction of said conveyor, a tube end therebetween thereby being progressively opened; bag bottom flap forming means including a plurality of spreader units, a pair of endless belts for moving and mounting said units, each of such belts being mounted upon a pair of wheels, corresponding wheel of each pair thereof being substantially parallel and positioned substantially side by side in overlapping relation and with the axes thereof parallel, said axes being spaced apart by a preselected distance in a common plane, said units being secured jointly to said belts at two locations, one for each belt, said locations being separated by a distance, measured along said belts, equal to said preselected distance whereby each of said units is movable along the path of said conveyor with an axis thereof always in a common attitude relative to the path of movement of the tubes moved by said conveyor, each of said spreader units including guide members and a pair of flexible tongue members retractilely mounted in such guide members, the latter being so constructed and arranged that the outer end of said tongue members are directed in opposite directions, each outer end of a tongue member being provided with a V-shaped corner flap shaping member secured thereto; said spreader units being moved by said belts for acting successively upon the opened tube ends after being Opened by said tube end opening means; and means for synchronously extending and retracting said pairs of tongue members in preselected relationship with the movement of said bag tube conveyor whereby a spreader unit is lowered into each oncoming opened tube end and moved therewith at the same speed thereof and corner and side flaps positively formed therein by said tongue members.

5. In an automatic bag bottom forming apparatus of the class having a bag tube conveyor including s aced gripping means for consecutively gripping a plurality of bag tubes near the opposite extremities and along the leading edge of each tube and moving same in succession relative to said apparatus, the combination comprising: tube end Opening means including a pair of oppo, sit ly isp ed suction cups for engaging o p site sides of the end of a bag tube and for pullin sameopen under the influence of suction and h movement of said cups, means for advancin said pair of suction cups along the path of: said conveyor for a substantial distance in order to allow said cups to grip a tube end, and mean for simultaneously moving said pair of suction cups from a closed position wherein they grip a closed tube end, to an open position wherein said cups are spread apart and said tube end is opened by a preseleted amount; and a nap forming device including a frame member, a pair of retractile flexible tongues mounted upon said frame member for extensile and retractile movement relative thereto, said frame member including guides for directing the outer extremities of said tongues for movement in opposite directions, means for simultaneously moving said flap forming device in the same direction and along with said ba tube conveyor, such last-named means inserting said device into a bag tube end which has been opened by said tube end opening means, means for extending and retracting said tongues while said flap forming device is so situated whereby side and corner flaps are positively formed in the tube end, and means for thereafter withdrawing said device from the open tube end.

6. In apparatus for automatically shaping the ends of bag tubes, such apparatus having a bag tube conveyor including spaced gripping means for consecutively gripping a plurality of bag tubes near opposite extremities along the leading edge f each tube and moving same in succession relative to said apparatus in preselected spaced relationship, the combination comprising: tube end opening means including a plurality of pairs of suction cups each adapted for grasping and pulling open the ends of a bag tube, the cups of each pair being mounted for movement relative to one another to accomplish such tube end opening, means for moving said pairs of cups linearly along the path of said conveyor, and means for simultaneously and progressively movin the cups of each pair from a closed position with the mouths thereof urged toward one another to a separated position; and a plurality of flap folding units each including a guide frame, a' pair of ilertible retractile tongues mounted in said guide frame, said tongues having inner and outer extremities, each of the outer extremities having secured thereto a flap shaping member, said guide frame guiding said outer extremities for motion in opposite directions, means for operatively associating the inner extremities of said tongues whereby a thrust thereupon simultaneously moves both the tongues; endless belt support means for said flap folding units for moving the latter into operative relation each with an open tube end as one of the latter moves into the orbit of said belt support means and a flap folding unit, means for operatively connecting said belt support means and said conveyor for movement in preselected phase relationship whereby said units are inserted successively into such open ends of successive bag tubes, and means for controlling the extension and retraction of said tongues when such units are so inserted.

7. In an automatic bag bottom forming apparatus the combination including a bag tube conv r. f r moving continuously a plurality of bag tubes in succession along a common path and consecutively past a plurality of units for forming a bottom in each of such tubes; and a tube end opener including: a pair of endless belts situated adjacent to one another and in a common plane, the latt r plane being inclined relative to said conveyor with the upstream extremities of s id lts po iti ned at a greater distance from said conveyor than the downstream extremities thereof, said belts having side runs which diverge from one another progressively in the direction of motion of said conveyor, a like plurality of suction cups mounted upon each of said belts in spaced relation thereon, said belts being movable in synchronism, each suction cup upon one of said belts having a corresponding and coacting suction'cup upon the other belt, said corresponding suction cups thus comprising a pair thereof, one on each belt, said cups being movable in phase with one another, and means for angularly shifting said cups moving on adjacent side runs of said belts progressively from a closed-opposed to a separated relationship.

8. In an automatic apparatus for shaping an extremity of each bag tube of a succession thereof, a bag tube conveyor including means for continuously moving in succession a plurality of bag tubes along a common path; and a tube end opener including: a pair of endless belts having inner runs, means for mounting said belts with such inner runs thereof extending generally in the direction of motion of said conveyor and with such inner runs spaced from but movable alongside one another, a preselected portion of such inner runs progressively diverging from one another as measured when moving in the direction of said conveyor, said means for mounting said belts being disposed for inclining said inner belt runs relative to such conveyor. a plurality of pairs of suction cups mounted on said belts, the cups of each pair being mounted one on each belt and movable in phase relation with one another, means for operatively interconnecting said belts for synchronous movement, and means for angularly shifting the cups of each pair thereof moving on adjacent side runs of said belts progressively from a closed-opposed to a separated relationship.

9. In an automatic apparatus for shaping an extremity of each of a succession of bag tubes, a bag tube conveyor including means for continuously moving in succession a plurality of bag tubes along a common path past a unit for shaping an extremity of each of such tubes; and a tube end opener including: a pair of endless belts having inner and outer runs, means for mounting said belts with the inner runs thereof spaced from but alongside one another and movable in the same direction with said conveyor, a preselected portion of such inner runs being substantially parallel to one another, the remaining portion of such inner run diverging from one another pro gressively along the'path of movement of said conveyor, said inner runs also being inclined relative to such conveyor with the upstream extremities thereof located farther from said conveyor than the downstream extremities, a plurality of pairs of suction cups mounted on said belts, the cups of each pair being mounted one on each belt and movable linearly in phase with one another, and means for angularly shifting the cups of each pair moving on adjacent side runs of said belts progressively from a closed-opposed to a'separated relationship.

10. In an automatic bag bottom forming apparatus the combination including, a bag tube conveyor for moving continuously a plurality of bag tubes in succession along a common path and consecutively past a plurality of units for forming bottoms in such tubes; a pair of endless belts positioned adjacent one another and alongside of said bag tube conveyor, each belt being mounted upon a pair of wheels, adjacent side runs of said belts extending along a common portion of the path of said conveyor, such side runs being closest to one another at their upstream extremities and diverging from one another progressively toward the downstream extremities thereof; a like plurality of suction cups mounted upon each of said belts in spaced relation thereon, said belts and cups being movable in synchronism, opposed pairs of cups one on each belt being movable in phase with one another, said belts being located in substantially the same plane and tilted with the downstream extremities thereof lower than the upstream extremities, and means for angularly shifting each pair of said cups moving on said adjacent side run from a closed-opposed relationship to a separated relationship; and tube end spreader means for acting upon such opened tube ends including: a spreader unit, the latter comprising guide members and spreader tongues retractilely mounted therein, conveyor means for moving such unit linearly in phase with said bag tube conveyor, and means for automatically and cyclically extending and retracting said'spreader tongues during operation of said unit conveyor means.

11. In an automatic bag forming apparatus of the class having a bag tube conveyor including spaced gripping means for consecutively gripping a plurality of bag tubes near the opposite extremities and along the leading edge of each tube and moving same in succession relative to said apparatus, the combination comprising tube endopening means; and a flap forming device including a frame member, a pair of retractile flexible tongues mounted upon said frame member for extensile and retractile movement relative there to, said frame member including guides having oppositely directed portions for directing the outer extremities of said tongue for movement in opposite directions, means for simultaneously movin said flap forming device in the same direc tion and along with said'bag tube conveyor, said last named means including a pair of endless belt conveyors mounted in side-by-side relationship, each of such endless belts being mounted upon a pair of wheels, the corresponding wheels of each pair thereof being parallel and positioned sideby-side in an overlapping but spaced relationship with the axes thereof parallel but spaced apart by a preselected distance in a common plane, said frame member of such flap forming device being secured to said endless belts at two locations, one on each belt, said locations being separated by a distance measured along said conveyors equal to said preselected distance separating the axis of corresponding .pairs of wheels thereof, said flap forming device conveyor belts being positioned for inserting said device in response to movement thereof into a bag tube end which has been opened by said tube end opening means, means for extending and retracting said flexible tongues in preselected phase relationship with the movement of said bag tube conveyor, and means for thereafter withdrawing said flap forming device away from said bag tube conveyor.

FRANCO GRAMEGNA.

' References Cited in the file of this patent UNITED STATES PATENTS Number