US2102766A - Method of forming valve bags - Google Patents

Description

Dec. 21, 1937. TQQKER 2,102,766

METHOD OF FO RMING VALVE BAGS Filed Aug. 29, 1934 3 Sheets-Sheet l- F ic:l.l.

INVENTOR JOHN M TOO/(ER ATT RNEYS' Dec. 21, 1937. TQQKER 2,102,766

METHOD OF FORMING VALVE BAGS Filed Aug. 29, 1934 5 Sheets-Sheet 2 MVENTQR JOHN M TOO/(ER ORNEYS' Dec 21, 1937. TQOKER 2,102,766

METHOD OF FORMING VALVE BAGS Filed Aug. 29, 1954 s Sheets-Sheet s NEYS I i EL INVENTOR JOHN N. TOO/(ER Patented Dec. 21, 1937 John N. Tooker, Canajoharle, N. Y., asslgnor to Bartlett Arkell, New York, N. Y.

Application August 29, 1934. serial No. 741,892

4 Claims.

valves are so formed as to ensure tight closing thereof when the bags are filled.

Other objects of the invention and advantages of the new method will be apparent as the description proceeds.

For an understanding of the invention, reference should be had to the accompanying drawings, in which Figure 1 is a plan view of a bag tube illustrating the first step in the method of forming the ba Figs. 2 and 3 are views illustrating successive steps in the forming of the valve end of the bag;

Fig. 4 is a. plan view of the-valve end of the completed bag; 7

Figs. 5 and 6 are perspective views of thevalve end of the completed bag showing the valve in open and closed position, respectively;

Fig. 7 is a vertical sectional view alonggthe line 'I-'-'l of Fig. 6;

Fig. 8 is a side view, partly in section and partly diagrammatic, illustrating the novel fea-' tures of the bottomer machine;

Fig. 9 is a transverse sectional view taken I along the line 9-9"of Fig. 8'and Fig. 10 is an enlarged detail view showing portions of the convex fold forming members of the machine of Figs. 8 and 9. I

The bag produced by my improved method is of the type of the one described and claimed in the pending application of Alfred Du Bois, Ser. No. 710,403, filed February 9, 1934.

In forming a pasted or satchel ended bag, a paper tube of thedesired number of plies is first cut by any suitable meansinto bag lengths such as indicated at 2 in Fig. 1. Each bag length has the usual serrated edges 4 and a centrally disposed tab 6 on one wall thereof at one end with a corresponding cut out 8 of the same wall at the other end. To form a pasted end bag, each such bag length is first cut longitudinally at one end to form slots l8. The slotted end of the bag length is then spread and flattened into t e position indicated in Fig. 2, with the end and I4 between corresponding slots l8 folded intions l8 and I8 spread. Paste;'indicated at 28 (Fig. 3), is then applied over the surface of wall portion 18 and over the greater part of the inwardly folded flap l2. No paste is applied to the flap 14, which serves as the valve when the bag is completed.

In the bag of said Du Bois application, the under flap of the valve is scored or creased to I form a hinged portion which is so arranged that it tends to snap firmly and tightly into engagement with the upper wall of the valve throughout the overlying portion thereof when the bag is filled and the filling tube is withdrawn.

In accordance with the present invention, suchcrease, which is convex on the outer surface of fiap l4, divides the fiap area into a substantially diamond shape portion indicated at 82 and a portion, indicated at 84, lying between the end of thetube and the folds 28 and the presses 22- and 24 are formed, the end of the bag tube is scored along parallel lines 88 and 88.

Score 86 extends transversely of the bag from the junction of folds 22 and 28 and simflarly score 88 extends transversely of the bag from the junction of folds 24 and 88. Wall portion I8 is then folded inwardly upon score line 88 and wall portion I6 is similarly folded inwardly upon score line 88 to form overlapping side flaps, and the 'or crease 22 of the valve lies adjacent the por-' tion of the fold 28 lying between the end of score 88 and slot l8. and crease 24 lies adjacent the portion of the told 88 lying between the end of score 88 and the corresponding slot I8. During filling. the end of the filling tube, indicated in dotted lines in Fig. 5, depresses the valve flap and forces the creases 22 and 24 downwardly. When the bag is filled and the filling tube-removed, the convex creases 22 and 24 cause the valve flap to snap into the position indicated in Figs. 6 and 7 in which a tight closure of the bag is eflected and the creases are positioned adjacent the upper folded parts pressed firmly together to cause the 88. After folded edges of the flap to form a seal therefor.

Upon closure of the valve, as shown best in Fig. 7 the central portion of area 36 of flap M lies flush with the top surface of the bag formed by the pasted overlapping wall sections i6 and i8, rein-= forcing the end of the bag and preventing seepage of the contained material toward the valve.

A machine adapted to carry out automatically the above described method is illustrated in Figs. 8, 9 and id l'he machine is of the general type now in use and known as a bottomer machine, but is modified to include means for forming the convex folds or creases hereinbeiore described in connection with Figs. 1 to 7 inclusive.

The machine includes the usual roll 38 and associated means (not shown) for-forming the slots l8 and for spreading the end of the tube, the usual flattening drum G2, a pasting segment 44 cooperating with a drum it and receiving paste from a paste roller dd through the inter.- mediary or roller 5t, and scoring rollers 52 for forming the transverse scores or creases 36 and 38. Pasting segment dd is rigidly secured to a shaft 53 for rotation thereby, and drum id is similarly secured to and rotated by a shaft to, shafts 54 and $6 being suitably driven in timed relation by means of gears 58. In order to adapt the machine to carry out my improved method, an arm. 66 is rigidly secured'atone end to shaft 56 to be rotated thereby. The other end of arm 55 carries a block 62 having a V-shaped groove dd therein which is disposed with its apex toward the pasting segment and its arms extending substantially at right angles therefrom. x An arm dd having at one end thereof a ll-shaped projection $8 for cooperation with the groove 64, issecured to drum 48 by means of a pin 'lfl to rotate therewith.

Adjacent the creaser arms $6 and 86 and rigidly mounted on shafts 54 and 56 is one pairof aligned pulleys H for engaging one lateral edge of the bag tube during passage thereof between the creasers and between the drum 46 and the pasting segment. A similar pair of aligned pulleys I4 is provided for engagement with the other lateral edge of the bag. Thus, as the flattened end of a bag tube advances from beneath the pressure roller 42 and passes over the drum 0 with its edges guided and held by pulleys -12 and 14 a portion "I6 ofthe pasting segment 44 first applies paste to wall portion l6. Immediately thereafter, during the application of paste to flap I! by a portion 18 of the pasting segment,'the arms and 86 move into position where projection 68 enters .groove 64 and forms the convex creases 22 and 24. In Fig. 10 the creasers are shown just prior to engagement. When the end of the bag length advances into position between rolls 52 the transverse scores 36 and 38 are formed.

Thereafter the wall portions l6 and I8 are folded by any suitable means (not shown) along the score lines 36 and 38 and pressure is applied to the pasted "portions. The bag length may then be run through another bottomer machine so as to close its other end in the usual manner.

It will be apparent as the desired creasing to form the hinged portion in the under flap oi the valve is preferably effected during the operation or closing the valve end of the bag tube, that this may be accomplished without interrupting such operation. Them-easing or hinge forming dell vices may be easily applied to the usual bottoming machine and when in use do not interfere with the speed of operation or the machine.

,As will be evident to thoseslrilled in the art, my invention permits various modifications without departing from the spirit thereof or the scope oi the appended claims.

What it claim is:

i. In the method of satchel ending a bag tube which includes opening and flattening the end oi the tube so as to provide inwardly directed corner flaps and longitudinally extending side flaps, and folding over the side flaps in overlapping relation and pasting them together so as to provide a satchel end with one of said corner flaps constituting the under flap of a valve, the improvement which consists in the additional step of creasing the under honor the valve when the end or the bag tube-is in said opened and flattened condition so as to provide a hinged portion adjacent a the end oi the upper wall of the valve when the satchel end has been completed, the hinged portion tending to cause the under flap or" the valve to lie tightly against the underside of the upper wall of the valve when the bag is filled and the valve is permitted to close.

2. In the making of a valve bag, the method of forming the valve'wluch includes spreading and flattening the end of a bag tube by infolding flaps at the median edge of the tube and then forming in one flap a pair of convex creases which extend from a point on the median fold of the tube ina direction away from the adjacent end of the tube and to the folds forming the edges of that flap.

- 3.,The method of forming valve type bags from bag tube lengths which includes infolding the valve flap and thereafter creasing the valve flap salts to provide adjacent the end of the upper wall of the valve a hinged portion which will lie; tightly-against the under side of the upper walll of the valve when the bag is completed and filled and the valveis permitted toclose.

4. The method of forming the valve end of a bag from a bag tube which includes forming longitudinal slits at one end of the bag tube, then spreading and flattening the slitted end of the tube to form infolded flaps between corresponding slits, thereafter applying paste to one of the. flaps and to the end of one wall portion between said flaps, forming a V-shaped crease, convex to the outer surface of the bag, on the unpasted flap positioned with its apex on. the median edge or the tube and its legs extending outwardly away from the adjacent end 01' the tube, and finally folding over the walls of the tube end along transverse lines terminating at the ends of the legs of said V -shaped crease.

JOHN N. 'rooxnn.

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