US2347902A - Bag making machine and method - Google Patents

Description

' May 2, 1944; R. J. GAUBERT BAG MAKING MACHINE AND METHOD Filed Nov. 6, 1940 a Sheets-Sheet 1 E a s INVENTOR S at E A 9? J. Gauber-f BY- @w 195? ATTORNEY y 2, 4- R. J. GAUBERT 2,347,902

BAG MAKING MACHINE AND METHOD File d Nov. 6,1940 8 Sheets-Sheet 2 INVENTOR Pena J. Gaub er/ wxm \ ATTORNEY ay 2,1944; I R J; GAUBERT 2347,92 BAG MAKING MACHINE AND METHOD Filed Nov. 6, 1940 8 Sheets-Sheet 5 INVENTOR Fer/e J. Gauber/ BY @..2 WM

ATTORNEY F-lE .:ElA

2, 11%44. R u -r 2 3473 BAG MAKING MACHINE AND METHOD Filed Nov. 6, 1940 '8 Sheets-Shet 5 A BNVENTOR ,ene J. Gauber/ ATTORNEY y2,1944. MGAUBE'RT 2,341,902

BAG MAKING MACHINE AND METHOD Filed Nov. 6, 1940 a Sheets-Sheets F'IIE' 'LE lNvNToR Pane Gauber/ AT TORNEY Figure 2;'

Patented May 2, 1944 BAG MAnmG MACHINE AND M THO Rene J. Gaubert, Oakland, Calif., assignor to Simplex Wrapping "Machine 00., Oakland, Calii'., a corporation of California Application November 6, 1940, Serial No. 364,593

2; Claims;

This invention relates generally to improvements in machines and methods for forming bags from sheet or rolled material such as moistureproof Cellophane or "Pliofilm in an automatic manner. I

The present construction is similar .to the bag making machine and method disclosed in my patent, Ser. No. 2,094,594, dated October 5, 1937, in

certain respects and employs certain of the inventions disclosed and claimed therein.

It is an object of the invention to provide a machine and method of the above character which, in a continuous and automatic manner operates to make bags from a roll of material of the character referred to by forming the bags and by making a T-shaped'se'al between the overlapping portions of the bag by the application of heat under pressure.

Another object of'the invention to provide a machine of the character referred to which is capable of high speed operation, which provides a compact feed and discharge construction for the b gs, and which provides for the optional provision of side tucks in the bags.

Another object of the invention is to provide a machine and method for making a substantially leak-proof bag of the character referred to.

Other'objects and advantages of the invention will be apparent from the following description in which a preferred embodiment of the invention has been described in conjunction with the ac companying drawings.

In the drawings:

Figure 1 is a side elevational View showing a machine incorporating the present invention;

Figure 2 is a plan view of the machine shown in Figure 1; i

Figure 3 is an enlarged longitudinal sectional view containing two portions, 3A and 33,. a indicated by the corresponding reference lines in v 0 Figure 4 is a bottom plan view partially in section and shown in twoparts, 4A and 413, as in dlcated by the lines A and 43 respectively in Figures 3A and 3B;

I' igure 5 is a detailed cross-sectional elevation of a part of the cam driven mechanism;

Figure 6 is a transverse cross-sectional view, taken in a plane indicated by the line 65 .in Figure 3B;

Figure 7 is a. transverse, cross-sectional'view taken as indicated by the line 1-1 in Figure 2;

Figure 8 is a longitudinal sectional vlewtaken as indicated by the line 8-8 in-Figure 2;

Figure 9 is an enlarged view illustrating the 55 the cut-off knives; v

Figure 10 is a detailed section of one of the relation of the end margin folding means and overrunning clutches as indicated by the line Ill-40 in Figure 7;

Figure 11 is a schematic view illustrating the 1 operation of the bottom fold mechanism;

Figure 12. is a schematic section illustrating a modified form of the invention useful in sealing leak-proof bags;

Figure 13 is a sectional view 5' lar to Figure 12 a but showing the partsin a erent operating position; a

Figure 14 is a schematic view illustrating the relation of the variousfolding plates for folding the material to the desired bag form;

Figure 15 is a fragmentary view of the end of a bag which is sealed in a leak-proof manner.

' The machine disclosed in the drawings in-' cludes a working table having a table top III which is supported by legs II. The machine is adapted to be driven by means of a suitable electric motor l3 (Figures 3 and 4) which is slidably secured to the bottom face of table top to by means of motor base It guided in ways'glif The motor shaft carries an adjustable pulley it which is connected by belt I! with a driven pulley l8 on a countershaft l9. Countershaft I9 is mounted in a gear box 2| which, through suitable reduction gearing, serves to drive the drive shaft 22 of the machine from whiclr the various'operating parts are driven ingtimed relation.

To vary the speed drive of the machine, the pulley may be of the conventional Reeves"' type which is self-adjusting in response to the tension placed on the belt ll to change the effective pitch diameter engaged by belt ii. To afford this adjustment a nut 23 (Figure 4A) is mounted onmotorbase it for engagement by a screw2l suitably'supported on the frame of themachine and having an operating handle 26. By adjust ing screw 24, the motor pulley i6 can'be moved toward and from the driven pulley i8 so that the belt n is automatically adjusted'to different di-' ameters of the driving pulley [6. To maintain the alignment of belt I1 and pulley IS, the ways l5 are inclined relative to the longitudinal axis of the machine.

Generally, the ,table referred to provides a working surface over which a continuous strip ofthe material is drawn in intermittent fashion, with guide means provided over the table for forming the strip of material into elongated tubular bag form with side tucks'provided if de-" sired, so that such bag-like" tube form is drawn adapted to receive a clamping bolt over a mandrel to which it is guided to a cut-off point. The

, material betweenthe point of light sensing and folding over of'the side edges of the strip provides overlapping marginal portions f along the edge of the form. After the cutting off operation (as later described) a bottom margin is folded over to. provide a generally T-shaped overlapping fold .for heat-sealing as later deioperation, the guide scribedi "the sealing plate or mandrelisadvanced to carry the folded and sealed end of the bag into engagement with a pair of feed rollers, which have just ejected the previously formed bag and which thereafter grip the sealed'end of the bag form and draw the selected baglength. In proper-timed relation, the .roller drive is released, preferably by light-. sensitive control, so that the cut-off ioperation can be performed to complete the bagformins operation.

This cycle of operation continues automatically so that bags are successively formed and ejected from the-machine. The various mechanisms for carrying out the cycle of operations will now be described in greater detail. Referring to'Figures 1 and 3A,a roll of material such as moisture-proof Cellophane" or Pliofilm is shown at 3|, being journaled in similar supporting brackets 32 mounted on the frame,

and a suitable spring-urged friction brake 33 being associated with the roll. To adjust the roll axially, the roll shaft 34 may be grooved for engagement by an adjusting screw 35 threaded in one of brackets 32. If desired, an auxiliary Y form along fora distance corresponding to the a the point of cut-off for a purposelater described. From roll 62 (Figures 1 and 3A), the sheet of material 36 extends downwardly to the table top l0 and is carried under a centrally disposed transversely extending guide bar H which is carried by bracket 12 depending from respective cross shafts I3 and 14 supported in the standards 05. Guide barll, is, supported in spaced relation from the table top ill and is of a width substantially equal to the total bag width to be formed, so that the side edges of the sheet tend to bend upwardly as indicated at I6 and-pass to either side of the bracket 12 in substantially upright position. The bar is'preferably detachably mounted on its supporting bracket so'that various bars of selected width can be used in accordance with the As the material passes the guide bar If and starts its initial travel over the table top ll, means is brought into play to provide an initial fold at each side edge of the material as a preliminary to forming the side tucks or folds of the bag form. For this purpose, a forming plate roll support in the form of brackets 32a may be provided below the brackets 32 to enable form-, ing of bags of double wall thickness.

As seen most clearly in Figure sheet of material 38 extends upwardly from the roll 3], over a stationary guide bar or roll 31' extending transversely between two projecting supv 'portingbrackets 38. Fronr roll 31, the sheet of material extends downwardly over a spring-urged roll 39 supported between respective arms I pivoted at on the frame. As seen most clearly in Figure .1, arms ii are urged in a counterclockwise direction by compression spring 3 disposed about a rod 44 which is pivotally connected to the adjacent arm ll.

From roll 39 (Figures 1 and 3A), the sheet of material extends substantially vertically upwards to roll 46, also supported between brackets 38.

Immediately below roll 46 a light-sensitive'cell 41 and a source of light 48 are disposed'at opposite sides of the sheet of material adjacent one edge thereof, bein'g supported on respective supporting rods 49 by respective collars 5! connected 3A, the stripor or mandrel ll .(Figures 2 and 3A) has its tapered end secured to the bracket 12 immediately behind the bar Ii and is of a width corresponding to the desired bag width, so that the side edges of. the sheet can be folded thereover to determine the bag width. The folding means includes opposed tuck plates or mandrels I2 supported from respective arms 83 slidably engaged with respective shafts N and 14 for slidin movement therealong. Intermediate the bars, each arm 83 is provided'with a threaded aperture to receive adjusting rod .4 having opposite threaded'portions and joumaled in standards 66.

7 Rod 04 is provided with operating handles u 'atitsends. Y

By operating handles 06' and rod 84, the respeetive tuck plates .2 are moved inwardly and outwardly so that their inward edges overlap the stationary plate ii to the desired extent of the .tuck to be formed in the sides of the bag. To assist in the forming operations, the leading edges of the tuck plate .2 may be curved asat l1 (Fie-v ure 2) to assist in folding over the side edges by U-brackets 52. a From roll 46 the sheet of material extends outwardly over adjustable roll 56 carried byre spective arms 51 pivoted at the ends of one of rods "by means of a slotted clamping hub 50. Each arm 51 is also provided with an arcuate slot 59 concentric with its pivot and 6| threaded in the adjacent bracket 38..

- From the adjustable roll 58 (Figures 1 and 3A), the sheet of material extends over a second adof the strip without injuryv thereto.

To maintain the edges of the sheet of mateiial upright, a pair '01 depending adjustable arms ll (Figures 2 and 3A) may be provided depending from collars I! on shaft I3 to engage the upturned edges of the sheet of material and maintain suchedges upright and with an inward turning tendency. v

The tuck folding operation is completed as the material moves along the tuck plates]! by means of a plate or mandrel II which extends lengthwise along the table top It and has its leading edge secured to av bracket 82 carried by rod ll slidably mounted in respective bosses J4 and ii of bracket 12. The mandrel." is thus mounted Y for endwise sliding movement fora purpose later described. The mandrel 0! 'may be provided justable rout: carried by respective adjusting arms '3 pivoted ontransverse'rod 64 supported in respective similar standards 55 on the frame. Each arm 63 is also provided with an arcuate'slot 61 adaptedto receive, a clamping bolt 68 threaded in theadjaeentjfstandard 66;

The provision, of

* 63 for and guiding a portion of the material enables the adjustment of the length of the adjustable armsb'l and I with a suitable fabric covering to facilitate the pressure heat sealing operation.

' The mandrel'or plate II is of the same width as. the stationary plate ll and is'held in spaced relation above the table top ll so that the tuck plates '2 extendinwardly between the bottom stationary platef IT and the overlapping portion of the mandrel SL. The edges of the sheet of material are folded over on top oflthe mandrel ll inoverlapping relation by the twisting tendany 'of the material as guided in reaching the I I22 for the upper roller.

mandrel SI, so that the bag formed passes from the stationary plate II, and the tuck plates 62 onto the mandrel, the longitudinal bag form is completed as shown diagrammatically in Figure 14. The'folded tuck portions remain folded dur- 6 ing'the subsequent travel of the material. 'Meansare provided for guiding the material into a laid with the side margins overlapping, and this means may take the form of a guide finger 01 suitably mounted on the bracket 12 and having its end bent, as seen most clearly in Figure 2 to engage over the adjacent ,edge portion of the material and under the opposite edge portion,

thereby insuring a proper overlapping relation of such edge portions v i To insure tensioning of the material in its final folded form, a floating tensioning assembly is provided in the form of a floating bracket IIII carrying respective friction rollers I02 for engaging therespective side portions of the'material 2 and urging such material inwardly over the mandrel 9|. Rollers I02 converge in the direction of travel of the material to cause tensioning thereof over the mandrel 9| as a preliminary to the final creasing of the side folds thereof. Bracket- IOI also carries a transverse bar I03 held in depending relation by adjustable studs I04 to aid in holding the material in place The bracket ill is pivoted at I06 (Figure 33) to the heater or sealing unit I01 and can be raised to place the rollers I02 and bar I03 in inactive position by engaging latch lever I08 with pin I09 suitably supported on the sealing unit I01.

From the above description, it is seen, that the sheet of material is folded into tubular form ofbag-like contour about the mandrel 9,I as it travels along the table in intermittent fashion as later described. The mandrel 0| as seen most clearly in Figure 3b extends to adjacent the end of the table top I0 so that the foldedtubular ma- 4o terial will be fed centrally along the table and projected past the table when initially fed into engagement with a pair of feedrollers 'I I6 and H1.

mittently and, as later "described may be disengaged from each other after the drive is interrupted at the desired time in accordance with the length of the bag being formed. ,After the feed of the rollers is interrupted, the end of the slidably disposed in the upright slotted end 'por- 6o tions I24 of brackets 1H6. Springs I26 held in place by suitable spring retainer brackets I21 above respective guides'l23 urge the roller II1 downwardly against the lower roller II6. Such engagement is adapted to be interrupted by roller disengaging links I26 slotted to engage c shaft I I8 and having forked ends engaging shaft pivotally connected to an arm I26 on a transverse shaft I3I suitablyv journaled. in brackets influence of spring I31. fl'hus, the upper roller The feed rollers II6, II1 are operated inter- 45 Each of links I26 is will be periodically lifted out of engagement with the lower roller under'the controlrof cam I36 in timed relation to the other cam driven opera tions including the drive for the rollers which ends just before the rollers are disengaged.

Means-may be provided for controlling, the

lifting of the roller to obtain an accuratelength.

of the desired bags from the light sensitive control means. Such means may comprise a solenoid I having its armature I42 connected by link I43 with arm I44 onshaft I3I so that upon energization of the solenoid the upper roller will be lifted, such lifting occurring ahead of usual drive for the rollers,'=therefore also ahead of the 5 timed lift from the cam control, which serves to release the tension on the bag form during the cutting operation which occurs with the bag form stationary.

The feed rollers are driven intermittently by adjustable means and for this purpose shaft II8 (Figures 7 and 10) is connected by one-way overrunning clutch I5I with gear sleeve I52 which is journaled on a reduced end of shaft I I8. Collar I53 is journaled about sleeve I52 and pro vides a-sliding support for drive rack I54 meshing with the gear portion of the sleeve. Rack I54 (Figure8) is pivotally connected to eccentric slide I55 threaded to receive screw I56 journaled in slide carrier I51 secured on drive shaft 0 22. Carrier I51 is provided' with suitable ways to. support slide I55 for endwise adjustment upon rotation of screw I56.

Screw I56 carries gear I56 which is adapted for engagement by either of pins I59a, I59b (Figures 6 and 8) carried by fork I6I journaled in the housing cover I62 and having adjusting handle I63. .By adjusting handle I63 from its central inactive position as shown ln Figure 2 to engage one of pins I59a or I59b with the gear I58, the adjusted position of the slide I56 can be controlled and thereby the extent of throw of rack I54. The rack I54 and the one-way clutch I5I are so related to the shaft II8 that they are active in driving as the rack movesto the right as viewed in Figure 8.

Referring again to Figure'l, at its left end shaft I I8 also carries one-.way overrunning clutch I66 having a drive connection with gear sleeve :I61'engaged with rack I66 which is'supported in collar I69.- Rack I68 (Figures 43 and 5) is.

connected at "I to earn follower slide 112 having suitable rollers engaging respective complemental cams I13 and I14 carriedby drive shaft 22. The arrangement of clutch I66 and .gear.

5 sleeve I61 is such that rack I66 drives in the same direction as the rack I54, 1. e., to the left as viewed in Figure 4B.

As seen inv Figure 7, shaft II6 has gear connection I16 with upper shaft I22 so that when' engaged the rollers are driven simultaneously.

' The cooperation of racks I54 and I68 in driving the rollers is described hereinafter in detail,

Rollers II6 and'II1 may be grooved "as at I11 intermediate their length to receive opposed strippers I18 which prevent sticking and serve to strip the bags from the rollers. Grooves I11 also prevent engagement of the sealed seam of the bags with the rollers.

As previously explained, immediately after the roller drive is stopped and the rollers are separated to relieve tension on the bag form, the cutting knife becomes active to cut oil the bag which has previously been formed.

As seen in- Figures 3B and 9, the stationary knife I6I is supported by knife holder I62 on the frame-in cooperative relation and beneath a.

reciprocating knife 109 having its cutting edge inclined for better cutting action. Knife I83 "is -pivotally-supported between similar links I04 and suitable spring-urged against an upright finger I85 of the knife holder which is engaged by the leading portion of the knife blade. Links I04-are pivotally connected at their upper ends .to supporting arms I" pivotally mounted on brackets I21. Links I94 are pivotally connected lat their lower ends to respective operating bellcranks I91 secured on transverse shaft "Ill. Shaft I80 also carries dependingarm I99 which is connected by link I9I with cam follower I92 urged against cam I99 by spring I94 associated with link I9I.

After the rolls-have been disengaged to remove the tension from the bag form, cam I93 allows spring I94 to become operative to move knife I93 downwardly to sever the bag form. This leaves an end margin of the bag form projecting beyond the table top I and meansis provided for folding this end margin to form the bottom a fold of the bag. To determine and retain the fold line for the end margin, a pair of horizontally disposed and inwardly projecting fingers 203 interposed. Block 202 is pivotally mounted at 204 on similar arms 209-secured on shaft 201. Spring 200 is tensionedbetween block 202 and pin 209 carried by depending arm 2 and having a pivotal slotted connection-to the operating link 212. Link 2I2 (Figures 33 and 4B) is pivoted to cam follower 2I8 which is operatively engaged with cam 2 under the influence of spring 2I9 associated with link 2I2, The slotted connection between pin 209 and link 2I2 is provided, with spring 2I5 which yields to allow overdriving bythe cam 2I4 and thereby avoid adjustment of the linlage to provide an exact stopping-point of the drive from cam 2I4.

Immediately after operation of the knife, the cam 2 becomes effective to move the folding blade 2 upwardly as indicated ln-the various positions shown in Figure 11, such movement being controlled not only by the pivoting movemerit of the bracket but also by the spring 200. Blade I is finally positioned in overlapping relation with respect to the end margin of the bag I form and with re'spectto the fingers I90, as shown in full lines in Figure ll. The end result of the folding operationis to places bottom fold transversely across the end of the bag formed over the mandrel or plate 9 I. i

r The folding over of the end margin for sealing "is eflected immediately priorto theoperation of the heater unit for sealing the overlapping seams by the application of pressure and heat. The heater structure I01 (Figures 2 and 38) includes a supporting casting 2I0 providing a pivotal support at 2I9 for a frame portion 22I. Frame 22I is generally I-shaped in plan and has mounted thereon a heater bar 222 forming the bar ofthe' T and a heater bar 223 forming the leg of the T.

cess 220 in which a suitable-electrical heating" 5 element 229 is mounted. 'l'hfejbottom surfaces 'of heater bars 222 and 222' provide a sharply formed, limited T-shap'ed"-pressing area ffor"ngagement with the overlapping portions of the bag. 'The bar 222-m ybe rigidly mada conncnbn 121. The bar'222 (Figure 3B) is preferablyprovided with a central pivotal connection 220 with frame portion HI and span of end guide connections 229 which allow limited vertical movement of the ends while maintaining the alignment of the bar. This provides afloating mounting for heater bar 222 which is self-align I ,and" has roller 239 and engaging heater control cam 24I on drive shaft 22. By adjusting screw 221 the position of heating unit I01 .can be controlled to obtain the proper movement thereof from cam 24I. 'nected thereto a link 242 (Figures 4A and 4B) which extends rearwardly to engage a compression spring 243 which urges the arm against the cam and normallyholds the heater unit elevated as shown in-Figure 33.

The heater unit can be rocked'downwardly from the position shown in Figure 33 so that T-shaped bar engages the overlappin end and v side-edge margins so that the overlapping portions of the Cellophane" or Pliofllm are held .in engagement between the mandrel and the heater bars for a sufficient time to efiect sealing operation. Usually mandrel 9I will be interposed throughout the entire length of the begin prevent sealing between the.upper and lower-portions. However, this interposition may be dispensed with along the end margin as later described. 9 Roller 244 (Figures 2 and 3B) which projects upwardly through the table top to'engage and facilitate feeding of the bag form is yieldably mounted to recede during the sealing operation. In order to control the temperature of the heater bars a thermostatic'switch is provided as shown generally at "I havinga conventional control button 262 to enable its operation; Preferably, the heat-responsive element 263 (Figure 3B) of theswitch is positioned within the heater bar 222. directly adjacent its heating element 226,

the external temperature condition thereof.

6 After the sealing operation, the rollers begin Q their drive synchronously with the advance of the mandrel 9i by the rack I to pick up thebag form and carry it into engagement with the rollers for feeding movement thereby. Cam follower slide I12 (Figure 5) is pivotally connected to an arm 24! (Figures 4A and 5) secured on shaft 240 suitably journaled on the frame. Shaft 240 carries arm 241 having a slotted pivotal connection with an arm 244 depending from cross shaft 14'. Shaft 14 (Figure 3A) also carries a frame portion 22I at s pair of spaced points of Arm 230 also has pivotally conplates of the proper width;

depending forked arm 2" engaging a pin: 25I

carried by collar 252 secured on rod 93 which, as

. engage the bag form and carry it forward until the rollers are again stopped, when the cutting off, folding, sealing, and advancing operations are again performed in sequence as described.

As seen in Figure 1, when the'bags are ejected from the machine, they are discharged into a bag holder or a discharge chute 253 adjustably mounted at one end by slotted link 254 and at the other end by adjustable rod 256.

In order to insure the forming of a leak-prof bag, I prefer to employ the type of construction illustrated in Figures 12 and 13 wherein the end of mandrel 9Ia is normally spaced from the end of the table top I 0a.

Figure 12 shows the mandrel Ella and one of the fold linefingers I9Iia for the end margin in normal position with the two sides 264a and 254b of the bag form projecting to the point of cut-oil. In Figure 13, finger I 96a has been advanced to set the fold line for the end margin of the bag form and folding plate 2IlIa has performed the folding operation. After withdrawal of finger I98a, the heater unit including element 222a will become operative to effect the seal. As shown in Figure 13, heater bar or element222a is offset downwardlyfrom bar 223a forming the leg of the T. With this construction, the endsealing operation'is applied throughout all thicknesses of the folded end margin as well as the walls 264a and 26,4b of the bag. proper. Immediately after withdrawal of the heater unit, the mandrel 8Ia is advanced and its first operation is to break the seal between the walls 264a, and 26417 of the bag except at the corners-of the bag before the seal has had time to set. The end corners of the mandrel may be cut away or 'rounded so that the seal at the corners is not affected. Also the operating means for the mandrel is preferably modified by providing a longer feeding stroke for the mandrel, so that after separating the desired portions of the bag walls, the mandrel picks up the bag form and advances it into en- 1 gagement with the feeding rollers as previously 5 described.

v Operation of the apparatus is'as follows: Assuming the machine to be equipped with forming and the tuck plates ,82v to be adjusted for the proper depth of tuck, the sheet of material, such as moisture-proof Cellophane or Pliofilm," is manually threaded through the machine over the guiding rollers, and through .and around the various forming plates including the mandrel 9| until its endds engaged with the feeding rollers. The tensioning rollers. operation, may then be engaged with the bag form. Also the adjustable slide I may be set manually to vary the effective throw of feed rack I54 (Figure 8) and thereby adjust the amount of feed of the bag from prior to interruption of the drive to the feed roller to thereby control the desired bag length. This adjustment may be made, however, during initial operation by manipulation of the adjusting handle I63; 'If the bags being-formed are provided with printed indicia, the handle I63 maybe employed to secure accurate cutting off at the length indicating .marks usually provided along the material.

which are released during the threading ment may be effected for positioning the adjusting rolls 56 and 62 so that the length bf material between the point of light sensing and the point of cut-off is an exact multiple of the desired length for one bag.

After proper adjustment of the machine, the

heating unit is turned on and when it has become sufliciently hot, the motor is also started and operation of the maehine begins.

After the first sealing operation, the bag form is advanced by'the mandrel 9| into engagement with the feeding rollers. The mandrel ill and the rack I68 which performs the initial driving of the feed rollers are both driven from slide I12,

and the arrangementis such that the peripheral j travel of \the rollers is the same as the linear .travel of the mandrel, thereby insuring'a gentle pick-up of the bag form by the rollers without injury. When the drive of the rollers by the rack I 68 is completed, the mandrel 9| is withdrawn. Subsequently the rack I54 begins its driving movement of the rollers. The adjustable travel of rack I54 by its slide I55 enables accu-. rate timing of the feed roller drive to control the extent of feed of the bag form. The machine therefore feeds the bag form for a predetermined extent in accordance with the required bag.

length. i

The drive rollers during ejection of the bag form serve-to flatten out the bag and sharply crease all the fold lines, and also, the rollers drive the air out of the bags. Both of these operations serve to aid stacking of the finished bags.

Th release of the feed rollers may optionally be placed under control of the light-sensitive cell upon interruption of the light beam by a marking dot to control the length of the bag.

When the feed of the bag form is interrupted and the rollers are released to relieve the tension, the knife I83 (Figure 9) becomes active to cut off the bag'which has been already formed and to provide an end margin for folding in the next bag to be formed. The folding plate 20I for the end margin then becomes effective to fold such end margin over fingers I96 into position for sealing by the heater unit. The fingers I96 are then withdrawn and the heater unit then becomes operative under control of its cam to seal both the overlapping side margins and the end margin. After release of the heater unit, the mandrel 9| is again advanced to initiate feeding of the bag form.

' The above-described cycle of operations is repeated as each successive bag is formed.-

It will be understood that the dimensions of the heater bars 222 and 223 are selected so as to be effected for the maximum length and width of bag which can be formedin'the machine. When forming bags of smaller width, the ends of the bar 222 will project beyond the sides ,of the bag, while in forming bags of shorter length the heater-bar- 223 will make a seal longer than.

Also. the light sensitive control of the drive j suillcient rapidity so that edge creases like "Cellophane" characterized by sheet said end margin,

understood that the length of feed of mandrel of the bag as to shortness,

9| limits the length while the maximum length is determined by the maximum feed .by the rollers and the length of the seal which can be applied. It will be understood that the machine can be employed also to form bags without side tucks by omitting the tuck plates- In operation for interruption of the V been pointed out that the rollers-should attempt to drive the bag form for a greater distance than that required for a bag, so that the 'light interrupting' mark will always be fed into the path of the light beam. At this time, the solenoid ill is energized and the rollers are separated to using the light sensitive means feed of material, it has tral portion of the'inner' faces of the bag walls adjacent said end margin while leaving, the

comers sealed.

2. In a machine for making bags from a continuous strip of material like Cellophane," a

.' with respect to the frame, means for directing interrupt the feed, this action taking place with the mark stops in light interrupting position and the solenoid remains energized. The separation of the rollers as with their c'am control, is not sumcient to disengage their gear, connection.- The solenoid remains energized until the mandrel 9| startsadvancing to feed the .bag-'form into' engagement with the rollers and thereby move the mark out of lightinterrupting position, as well as restarting the cycle of operations.

With particular reference to the operation with the mandrel Bla as shown in Figures 12 and 13, it will. be noted that after the withdrawal of the fold line retaining fingers shown in Figure 13, the heater bar 222a is effective to apply heat under pressure through the entire layers of the bag form including the actual en an effective and seal is applied across the entire advanced, it serves tion of the seal between the two adjacent walls [96a from the position the strip of material along one face of the mandrel, means for folding projecting side margins of the strip over the mandrel to provide an overlap between the edge portionsof said margins, means for feeding said strip, said folding means operating during feeding of said strip, means for periodically interrupting the feed of said strip,

'means for folding--a projecting end margin of the strip of material'over one end edge of the mandrel to provide an end overlap during interruption of said feed, heat sealing means, means forapplying said means to said overlapping portions to effect a seal, and means for advancing said mandrel to engage the sealed bag end with said feeding means. v

3. In a machine for making bags from a continuous strip of material like Cellophane, a frame, a plate-like mandrel mounted for reciprocation on said table, meansfor directing the strip of material along one face of the mandrel, means for folding projecting side margins of the strip over the mandrel to provide 'an overlap widthofthe end margin seal. Subsequently, when themandrel Sla is to immediately break a porof the bag, but it does not affect the'seal made along the folded over and margin which is sealed for its entire length including its side edge creases at the corner portions of the bag. For example, as shown in Figure 15, the bag Iii is shown as having a seal 261 extending entirely across the end margin as indicated by the shading; seal is effective between the folded over and margins of the two side walls as well as between the,

adjacent side wall and the adjacent marginal portion. The extent of the seal through the varperature of the heater unit and the length of application of the heater unit in effecting the seal.

With the construction. shown in Figure 13, it is preferred to have the upper plate or mandrel 9|.slightly wider than the plate ll so that the creases 269 for direct creasing and seallngbe- .tween the table top and the heater bar.

the bag wall and with said overlapping side margins;then applying heat under pressure directly through all of the overlappingportions; along 268 adjacent the folded, over end. margin will project beyond the opposite edge.

the use of a;

of the finished bag,

and then separating the cen-.

- ious thicknesses is controlled in part byvthe tem- ,machin' e between the edge portions of said margins, means for feeding said strip, sai folding means operating during feeding of said strip, means for periodically interrupting the feed of said strip,

means for cutting of! said strip during interruption of said feed, means for folding a projecting end margin of thestrip of material through to provide an and overlap during interruption of said feed, a heater, means for applying said heater to said overlapping portions'to effect a seal during interruption of said feed, said mandrel being spaced from said end overlap during the sealing operation, and means for advancing said mandrel to first partially break the seal between the walls of said bag aligned with saidgnd overlap and to thereafter engage the seale with said feedin means. J 4. In a machine for making bags from a continuous strip of material like "Cellophane," said.

machine being characterized by the folding of the bags another and subsequently acting part havinga' variable driving action.

6. In a machine for making bags from a continuouss'trip of material like Cellophane, said being characterized by the folding of the bags about a mandrel, said mandrel bein mounted for reciprocating movement, a pair of feed rollers for receiving folded material from said mandrel, drive means for said feed rollers including apair of reciprocating racks, a oneway .overrunning clutch between each; of said .racks and said rollers, means for driving One bag end about a mandrel, a pair of feed rollersfor receiving folded material from said mandrel, I and means for driving said feed rollers, said 4 driving means including having an invariable driving action and p a of said racks in its active direction of movement in time with the material feeding movement of said mandrel, and means for subsequently driving the other rack in its active direction of'movement in timed relation to the driving movement of said first rack to advance said material in accordance with the desired length of bag.

7. In a machine for making bags from a con-. tinuous strip of material like Cellophane, said machine being characterized by the folding of the bags about a mandrel, said mandrel being mounted for reciprocating movement. a pair-of feed rollers for receiving folded material fromsaid mandrel, drive means for said feed rollers lneluding a pair of reciprocating racks, a one-Way overrunning clutch between each of said racks and saidrollers, means for driving one of said racks in its active direction of movement in time mandrel. whereby the material is. engaged with said rollers while moving at substantially the same speed, and means for subsequently drivin the other rack in its active direction of move ment to advance the material, the drive means for said last-named rack including means for varying the extent of travel imparted to said rollers without varying the timed relation to the operation of said first rack.

8. In a machine for making bags from a continuous strip of material like Cellophane? said machine being characterized by the folding of the bags about a mandrel, said mandrel being mounted for reciprocating movement. feed means for receiving folded material from said mandrel, drive means for said feed means including one part having an invariable driving movement and for reciprocating movement, feed means for receiving folded material from said mandrel. drive means for said feed means including one part havposition of said slide during rotationfth with said shaft. p

11. In a machine for making bags fr 2a continuous strip of material like Cellphane,""said machine being characterized by the folding of the material about a plate-like mandrel, a pair 'of'fe'ed rollers positioned adjacent an end of said mandrel for receiving folded material therefrom, means for moving said mandrel to feed folded material to said rollers, andmeans forinterrupting' the feed,of material by said rollers including means for separating said rollers.

'with the material feeding movement of said 12. In a machine for making bags from anontlnuous strip of material like Cellophane? a frame, a plate-like mandrelabout which the material is folded, means including a pair of feed rollers-forreceiving material from said. mandrel. light-sensitive means responsive to indicia on said material, and means controlled by said light sensitivemeans for interrupting the drive oi said 7 feed rollers with respect to the material.

13. In a machine for making bags from a continuous strip of material like Cellophane, means for supporting and folding said material into a bag form, means for feeding material along said supporting and folding means. light-sensitive means responsive to indicia on said material, and means controlled by said light-sensitive means for interrupting the drive of saidfeeding means H with respect to the material.

14. Ina machine for making bags from a continuous strip of material like "Cellophane said machine being characterized by the folding of the material about a plate-like mandrel, -a pair of feed rollers positioned adjacent an end of sa d mandrel, means for yieldably urging said rollers into engagement, means for moving said mandrel to feed folded material to said rollers, Cyclic dri e means for said rollers, means for eflecting an ad- J'ustment of theextent of feed of said rollers in a given portion of each cycle of feed, means for overcoming said yieldablefengaging means to dsengage the rollers from the material to relieve the tension thereon, and means for cutting said material. j

15. In a machine for making bags from material like "Cellophane," means including a platelike mandrel for folding material into a bag form, said folding means including means for placing the side margins of said material in overlapping relation andan end margin of said materialin ing an invariable driving movement and a second part having a variable driving movement, means for operating said one part in time with the material feeding movement of said mandrel, and means for subsequently operating the other part of said drive means in timed relation to the driving movement of said first part to. advance said material in accordance with the desired length of bag, the second part of said drive means including means for varying the extent of travel imparted to said feed means whereby to control the length'of bag being formed.

10. In a machine'for making bags from a continuous'strip of material like Cellophane, said machine being characterized by the folding of the bags about a mandrel. a pair of feedrollers for receiving folded material from said-mandrel. and means for driving said feed rollers, said' driving means including a drive shaft, a slide mounted for rotation with said drive shaft and for adjustment axially of said drive shaft, a rack connected to said slide for reciprocating movement thereby, 'an overrunning clutch between said-rack and said feed rollers, and means for adjusting the overlapping relation with respect to the length of material to provide a T-shaped area of overlap:

ping portions of the material, said mandrel'be-- margin, and a T-shaped heater unit mounted to engage said T-shaped overlapping area, said T- shaped heater unit having itsportion forming the bar of the T offset downwardly from its portion forming the leg of the T.

'16. In a machine for making bags from a continuous strip of material like Cellophane," said material having a series of equally spaced lightinterrupting marks along its length, a frame, a, plate-like mandrel about which the material is folded, means including a pair of feed rollers for receiving material from said mandrel, lightsensitive'means for sensing said marks, means controlled by said light-sensitive means for separating said rollers upon sensing of a mark by said light-sensitivemeans to interrupt the feed of material with said markjin active position, and means for advancing said mandrel to feed from its active position, whereby said separating means ls'rendered ineffective.

. 1'7. In a machine for making bags trom a con-- tinuous strip of materiallike Cellophane, said material having series of equally spaced, light responsive indicia along its length, a frame, a

plate-like mandrel about which the material is. folded, feed means for receiving material from said mandrel, light sensitive means for sensing said indicia, means controlled by said light sensitive means for disabling said feed means upon sensing of an indicia by said light sensitive means to interrupt the feed of materialwith said sensed indicia in activepositi n. r o

18. In a machine for making bags from a continuous strip of material like Cellophane, said material havingseries. of equally spaced, light responsive indicia along its length, a frame, a plate-like mandrel about which the'materiai is folded,.feed means for receiving material from said mandrel; light sensitive means for sensing said indicia, means controlled by said light sensitive means for disabling said feed means upon sensing of an indicia by said light sensitive means to interrupt the feed of material with said sensed indicia in active position, and means for advancing said mandrel to feed material to said. feed means and also to move saidsensed indicia from its active position whereby the feed means is again rendered eflective.

19. In an automatic machine for forming bags from a'strip or ribbon of fusible material like .mois'ture-proof Cellophane," means for forming an advancing portion oithe strip into a relatively flat tube, saidmeans including a platelike mandrel about which the tube is formed, means for folding an end margin of the tube over the forward end of the mandrel,- means forming a heat seal across the folded end margin to make the bottom of a bag, discharge means for gripping the end of the tube and for withthe mandrel, means for severing the tube near the forward end of the mandrel after a predeter-.

mined length ofthe tube has-been withdrawn ing an advancing portion of thestrip into a relatively flat tube, said means including a platelike mandrel about which thetube is formed, means for folding an end margin of the tube over the forward end of the mandrehmeans forming aheat seal across the folded end margin to make the bottom of a bag, discharge means for-gripping the end of the tube and for withdrawing the tube in a forward direction from the mandrel, means for severing the tube near the forward end of the mandrel after a predetermined length or the tube has been withdrawn whereby the withdrawn portion forms a completed bag, and means for reciprocating the mandrel to advance the tube toward the discharge means.

21. In an automatic machine for forming bags .from a strip or ribbon of fusible material like moisture-proof Cellophane, means for forming an advancing portionof the strip into a relatively flat tube, said means'including a platelike mandrel about which the tube is formed, means for folding an end margin of the tube over the forward end of the mandrel, means forming a-heat seal across the folded end margin to make the bottom of a bag, discharge means including rollers for gripping the end of the tube and for withdrawing the tube in a forward directionfrom the mandrel, means for severing the tube near the forward end of the mandrel after a predetermined length of the tube has been withdrawn whereby the withdrawn portion forms a completedbag, and means for reciprocating the mandrel to advance the tube toward the discharge means.

drawing the tubein a forward direction from whereby the withdrawn portion forms .a completedbag, and means for advancing the tube toward the discharge means immediately after sealing of the'folded over end margin of the same and before gripping'of the same by the discharge means. H W

20. In an automatic machine for forming bags from a strip or ribbon of fusible material like moisture-proof fCellophane. means for formmeans immediately after operation of said end j 22. In an automatic machine for forming bags from material like moisture proof Cellophane,

means for forming a sheet portion of the material into a relatively flat tube, said means including a plate-like mandrel about which the tube is formed, means for folding a projecting end margin of the tube through an angle of substantially and over a forward end of the mandrel, means forming a heat seal across the folded end margin to make the bottom of a bag, discharge means for gripping the folded end of the tube and for withdrawing the tube in a forward direction from the mandrel, and means for advancing the tube toward the discharge folding means and after sealing of the folded over end margin of the same and before gripping of the same by the dischargemeans.

. RENE J. GAUBERT.

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