USRE22292E - Bag making machine and method - Google Patents

Description

March 23, 1943'.

\ BAG MAKING MACHINE AND METHOD Original Filed April 26. 1935 '7 Sheets-Sheet 1 INVETOR. ,QeneJGaL/b er-f ATTORNEY.

March23, 1943. V J U ERT Re. 22,292 I BAG MAKING MACHINE AND METHOD Original Filed April 26, 1955 '7 Sheets-Shet 2 F'IE E 24 10 13 6/ :HW ea;

INVENTOR. E fieneJfial/berf ATTORNEY.

R. J. GAUBI ERT BAG MAKING MACHINE AND METHOD March 23, 1943.

Original Filed April 26, 1935 7 Sheets-sheaf 3 PIE '7 FIE E I I g /z/ /2/ 57 m 47 Z? Z /26 3 55; 47b 21 m 4 24/45 727 ff m3 INV ENTbR.

ATTORNEY Marh 23, 1943. R, GAUBERT Re. 22,292

BAG MAKING MACHINE AND METHOD Original'Filed April 26, 1955 7 Sheets-Sheet 5 F':[|5 1a 94 v /05 Q1/0122 ATTORNEY.

March 23, 1943. 1 u -r Re. 22,292

BAG MAKING MACHINE AND METHOD Original Filed April 26, 1955 '7 Sheets-Sheet 6.

F'Il5 l4 Inge/W ATTORNEY.

March 23, 1943 GAUBERT Re. 22,292

BAG MAKING MACHINE AND METHOD Original Filed April 26,-- 1955 7 Sheets-Sheet '7 I -"1NVENTOR. Fer/e J Gin/her? BYWMW ATTORNEY.

Reissued Mar. 23, 1943 BAG MAKING MACHINE AND METHOD Rene J. Gaubert, Oakland, Calif., assignor to Simplex Wrapping Machine 00.,

Oakland,

Calif., a corporation of California Original No. 2,094,594, dated October 5, 1937, Serial No. 18,289, April 26, 1935. Application for reissue July 22, 1942, Serial No. 451,965

8 Claims.

This invention relates generally to machines and methods for forming bags from sheet material such as Cellophane.

It is an object of the invention to provide a machine and method of the above character which will dispense with the conventional practice of gluing together the overlapping edges of sheet material after the sheet is folded to form the bag. In this connection the present invention employs moisture-proof Cellophane," which makes possible a seal between overlapping portions by the application of heat and pressure.

Another object of the invention is to provide a machine of the'above character which will not be unduly expensive with respect to first cost and maintenance, and which can therefore be used by department stores, mail order houses, bakeries and the like, to form simple types of bags directly from Cellophane stock. Up to the present time it has been customary for such establishments to purchase Cellophane bags made by bag manufacturers, at a relatively high cost. My machine, because of its low cost and ease of operation, will make possible the manufacture of bags as they are required by such establishments, at a considerable saving.

Further objects of the invention can be briefly outlined as follows: To afford relatively high capacity with minimum requirements with respect to door space and skill of the operator; to afford mechanical movements which will perform the necessary folding and sealing operations without undue mechanical complications and with a minimum amount of power consumption; and to enable sealing over all of the required areas in a single operation, in cyclic sequence with preceding folding operations.

Further objects of the invention will appear from the following description in which the preferred embodiment of the invention has been set forth in detail in conjunction with the accompanylng drawings.

Referring to the drawings:

Fig. 1 is a side elevational View showing the machine incorporating the present invention.

Fig. 2 is a plan view, showing the heater incorporated in the machine of Fig. 1.

Fig. 3 is a cross-sectional view taken along the line 3-3 of Fig. 1.

Fig. 4 is a cross-sectional detail taken along the line 4-4 of Fig. 3.

Fig. 5 is a cross-sectional detail taken along the line 5--5 of Fig. 4.

Fig. 6 is a cross-sectional detail taken along the line 6-6 of Fig. 3.

Fig. 7 is a cross-sectional View taken along the line 1-1 of Fig. 1.

Fig. 8 is a cross-sectional detail taken along the line 8-8 of Fig. 7.

Fig. 9 is a cross-sectional detail taken along the line 9-9 of Fig. 3.

Fig. 10 is a detail similar to Fig. 9 but showing the heater in a diiferent operating position.

Fig. 11 is a cross-sectional detail, illustrating a modification in which an article is being wrapped simultaneously with the formation of a bag.

Fig. 12 is a side elevational detail of the heater structure.

Fig. 13 is a side elevational detail showing cam means for operating the side folding members.

Fig. 14 is a plan view, partly in cross section, showing a preferred modification of the machine.

Fig. 15 is an end detail view of one-half of the table and associated parts, showing particularly the'elements serving to interconnect side folding members, with end fold line retaining members.

Fig. 16 is a cross sectional detail taken along the line l6-l6 of Fig. 14.

Fig. 17 is a cross sectional detail, showing mechanism employed particularly for the purpose of retracting the end fold line retaining members.

The machine as illustrated in the drawings consists of a frame forming a working table, there being a table top ill with supporting legs I l. A suitable source of electric power is provided, such as an electric motor 12. By means of a cyclic drive mechanism, designated generally at l3, the electric motor I2 serves to cyclically reciprocate a vertical shaft l4. Particularly from the standpoint of simplicity of construction, it should be noted that all of the working parts of the machine to be subsequently described are arranged to be operated by reciprocation of this shaft, although it is evident that in some instances a more elaborate form of mechanism for interconnecting the working parts with the electric motor may be desirable.

The cyclic drive means l3 has been shown including a gear box l5, to secure a suitable reduction in speed. The gear box drives a crank disc l5, through a suitable one-revolution clutch [1. A crank rod 18 serves to connect the lower end of shaft I4 with the crank disc IS. The trip I 9 for the one-revolution clutch I1 is shown connected to a foot lever 2|, whereby when this lever is depressed manually, clutch I! is engaged to drive crank disc l6 one revolution, after which the clutch is automatically tripped. A suitable guide journal 22 for the shaft id is shown being carried by a depending bracket 23, which in turn is secured to the frame of the machine.

A suitable detail for the table top can be best understood by reference to Figs. 3 and 6. A pair of cover plates 24 are provided, which are secured to the upper surface of the table H] by the spacing studs 25. These plates extend from the rear to the forward end of the machine, over the side areas of the working table, and, assuming that a simple type of rectangular bag is to be made, the inner longitudinal edgesv 26 are parallel. The upper surface of the working table, extending between the longitudinal edges 22, forms a flat operating surface 21', with which a sheet 28 of Cellophane or like material of which the bag is to be made, can engage.

In order that a sheet of mater al can be readily centralized upon the work table by an operator, suitable gauging or centralizing devices iii are provided. These devices may be duplicates and can be conveniently mounted upon the cover plates 24. The one device 3| illustrated in Fig. 3 consists of the bar 30, eX- tending parallel to the longitudinal edge 26 of the corresponding cover plate 24, and carried by one end of a rod 32. This rod is slidably carried by a bracket 33, which in turn is mounted upon the plate 24. By means of a set screw 34, the distance between bar 3i] and the longitudinal center line of the working table, can be adjusted. Gauge pins 35 (Figs. 1 and 3) are also provided near the forward edges of plates 24, to facilitate properly locating the forward edge of the sheet. Gauge blocks 29 are also carried by bars Bil, to engage the rear edge of the Cellophane sheet, and these blocks are adjustable forwardly and rearwardly of the machine.

One of the elements utilized during the folding and sealing of sheet 28 is a plate-like mandrel 35. In accordance with the previous assumption that simple, rectangular-shaped bags are to be made, this mandrel is rectangular in contour, and for the larger sizes of bags, it has a width slightly less than the distance between the edges 28 of the cover plates 24, and with the plates disposed substantially in alignment with the longitudinal center line of the working table, when. The rear end of viewed in plan as in Fig. 3. plate 35 is detachably secured to a shaft 31 which in turn has a pivotal connection 38 with a fixed bracket 39 forming part of bracket 23. Since the axis of the pivotal connection 38 is horizontal, the mandrel has pivotal movement in a vertical plane, towards or away from the table surface 21. It may be explained at this point that when mandrel 36 is in itslowermost position, it directly engages the upper side of the Cellophane sheet 28, with this sheet being located between the mandrel and the surface 21. Assuming that the sheet 28 has been properly centralized, its equal side margins 28a can be folded over the side longitudinal edges 36a of the mandrel 36. Likewise, a forward end margin 28b is provided, which can be folded over the forward edge 38b of the mandrel.

While raising and lowering of the mandrel 36 might in some instances be carried out manually, automatic operation of the mandrel. is

preferred. For this purpose a clamp 4|, in the form of a cross-head, is shown secured to the vertical shaft M. A pair of pins 42 extend upwardly through bracket 23 and have their lower ends secured to the clamp 4|. The upper ends of these pins are adapted to engage the under side of casting 38, whereby when shaft M is in the upper limit of its travel, mandrel 36 is elevated to substantially the position shown in Fig. 9. When shaft l4 moves downwardly, it is apparent that lowering of pins 42 permits mandrel 36 to drop down upon the table surface 21 under the urge of gravity and tension spring 43;

The means illustrated for effecting a foldingover of the side margins 28a includes the followingelementsLUnderlying the cover plates 24 are the folding, members 44a and 4411. These memhere are in the form of elongated strips of flat metal bars. In order to guide these bars for parallel'movement in opposite direction, the rear end of each member is secured to rods 45a and 45b, which in turn are slidably carried by the brackets 46.. As representative of suitable means for properly'actuating folding members 45a and 44!), a pair of. levers 41a and 41b are provided,

which are carried by pivot pins 48 upon the bracket, 23. The upwardly extending arms 49a and 42b of these levers have pivotal connections 5|w to links 52 which are connected to the inner ends of. rods 45a and 45b. The clamp or crosshead 4| on shaft |4 carries a pair of rollers 53a and 531), which cooperate with suitable cam surfaces on the levers 41a and 41b. The different portions of the cam surfaces on lever 410. have been designated by numerals |a,2a, 3a,, 4a and 5a, and the corresponding portions on lever 41b have been designated by numerals lb, 21), 3b, 4b and 5?). With the exception of portions la and lb,

all of the cam portions are formed on the lower depending arms 54a and 54b of the cam levers.

The manner in which these cam levers operate will be presently described in greater detail. For the present, it may be noted that when the shaft M. is in the uppermost limit of its travel, the cam portions |a and lb are engaged, and the folding members 44a and 44b are in their retracted positions, as illustrated in Figs. 6 and '7. However, when shaft l4, together with cross-head 4|, is moved downwardly, the cam portions 0n the arms 54a and 5411 are engaged, thus causing the cam levers to rotate in opposite directions, to move the folding members 44d and 44b inwardly in opposite directions overthe mandrel 36.

For at least the initial part of the inward movement of folding members 44a and 44b, it is desirable to have them elevated with respect to the upper surface of mandrel 36. For this purpose an arm 55 is secured to an intermediate part of each folding member (Figs. 3 and 6). The outer end of each arm 56 carries a button or pad E'Ladapted to slidably engage the upper surface of a bar or strap 55. The under side of each folding member carries a plurality of spaced leaf springs 58. These springs gently engage the upper surface of the mandrel, to facilitate formation of. a distinct fold to somewhat tighten the sheet'upon the mandrel, and to hold the folded margins during the sealing operation.

It has been previously explained that when the machine is being operated, a sheet of Cellophane is arranged below the mandrel 35 and is located to afford not only the substantially equal side margins 28a but also the forward end margin 28b. To assist in properly folding thisend margin of the sheet over the end edge 36a of the mandrel, means are provided as follows: Transverse channel guides 6| are mounted adjacent the forward end of the table In, beneath the cover plates 24. Fold- line retaining members 62a and 62b, in the form of thin metal strips or blades, are slidably disposed in these guides.

Instead of supplying separate mechanism, taking its motion directly from shaft I4, members 62a. and 62b can be automatically operated by simple mechanism interconnecting them with the folding members 44a and 44b. Thus as shown in Fig. 3, a lever 63 has a pivotal mounting E4 to the table I6, and is disposed beneath the corresponding cover plate 24. The free ends of levers 63 have pin and slot connections 66 with the corresponding folding members. A tension spring 61 is provided, tending to swing each arm 63 outwardly, thus tending to bias the corresponding fold-line retaining member (6211 or 6%) towards retracted position. In addition to the lever 63, a trip lever 68 is provided, which likewise has its one end pivotally mounted to the table ID. This lever is connected to the corresponding side folding member (44a or 44b), by means of link 69. The free end of lever 68 is adapted to engage a pin 12, carried by the corresponding end retaining member (62a or 62b). The action is such that when the side folding members are moved inwardly, engagement of levers 68 with pins 12 likewise causes the end retaining members 62a and 62b to move inwardly over the forward edge of the mandrel 36. However, before the side folding members 440. and 441) have reached the limit of their inward movement, pins 12 escape by the ends 1| of the trip lever, thus permitting the end folding members 62a and 62b to be snapped back to their retracted positions, as illustrated in Fig. 3, under the pull of springs 61. It will be noted in Fig. 3 that the inner ends of the members 62a and 62b terminate short of the inner edges of the side folding members 44a and 44b when all of the folding members are in their retracted positions.

To carry out a folding operation to form the bottom of the bag, a folding and gripping device 13 (Figs. 4, 5, 9 and 10) is provided. In the form illustrated, this device consists of a bar 14, carried by an L-shaped member 16. In order to secure the type of motion desired for the clamping bar 14, member 16 has a pivotal connection 11 with one arm of an L-lever 18. This L-lever in turn is carried by a fulcrum pin 19, which is fixed with respect to the table 18. Slidably mounted beneath the table l there is a rod 86, the forward end 8| of which is adapted to engage that portion of the member 16 to which the bar 14 is attached. Likewise, the forward end of rod 89 has a pivotal connection 82 to the other arm of the L-lever 18. The member 16 is normally biased in a counter-clockwise direction (as viewed in Fig. 4) about the pivot connection 11, by the tension spring 83. It will be noted that one end of this tension spring is shown anchored to member 16, at a point forwardly of both the pivotal connection 11 and the pivot pin 19, while the other-end of this spring is anchored to the forward end 8| of rod 89.

With the arrangement described above, as rod 89 is moved to the left, as viewed in Fig. 4, member 16 under the urge of spring 83 is caused to swing in a generally counter-clockwise direction, to elevate bar 14 and to translate the same to a position overlying the forward edges of retaining members 62a and 62b and the forward edge 36b of the mandrel 36 (assuming that mandrel is in its lowered position). When in such position, further movement of bar 14 towards the rear of the machine is arrested by the stop pin 84. Continued movement of rod towards the rear of the machine causes a lowering of the pivotal connection 11, and such lowering movement (which occurs after retraction of members 62a and 62b) is accompanied by a general lowering of the entire member 16, so that bar 14 is dropped into yieldable gripping engagement with the folded margin 28b of the sheet of Cellophane. Conversely, return movement of rod 80 towards the forward end of the machine first causes bar 14 to swing back substantially to the position shown in solid lines in Fig. 4. In the folding operation just described, it is evident that members 62a and 62b properly hold down the adjacent portion of the "Cellophane sheet, to avoid undesirable creases and to facilitate formation of properly folded corners and a distinct bottom fold line.

The means for effecting reciprocation of rod 80 can be best understood by reference to Figs. 9 and 10. Thus, the representative means il1ustrated includes a roller 86, carried on the forward side of cross-head 4 I. Secured to the rear end of rod 89 there is a cam finger 18, the surfaces 88 and 89 of which are adapted to engage the roller 86. A compression spring 9|, surrounding rod 80, normally urges this rod, together with finger 81, towards the roller 86. It will be noted that cam surfaces 88 and 89 are parallel with respect to the travel of shaft 1 4, and that surface 89 is offset forwardly with respect to surface 88. Therefore, while shaft I 4 is in the upper portion of its travel, with the roller 86 in engagement with surface 88, the device 13 is retained in its released position, as shown in Fig. 9. As the crosshead 4| moves downwardly it passes beyond the lower end of surface 88, and thereupon finger 81 and rod 80 move rearwardly a limited amount, until the roller 86 is in engagement with surface 89. Such movement is sufficient to bring bar 14 into an elevated position above the forward edge 36b of the mandrel 36. As the cross-head 4| moves downwardly a further amount, it finally passes below the lower end of finger 61, with the result that further rearward movement of rod 80 serves to bring bar 14 into clamping engagement with the blades 62a and 62b.

For the sealing operation following folding of the side and end margins of the sheet of "Cellophane over the mandrel 36, a heater structure 92 is employed. While the details of this structure may vary in practice, it has-been shown including a heater 93, secured to a comparatively rigid backing 94. The heater itself is generally T-shaped in plan profile, as shown in Fig. 2, and its body 96 can be formed of suitable metal. The body is hollow to afford an inner recess 91, which accommodates a suitable electrical heating ele ment 98. The lower face of the body 96 has its edges cut away, as indicated at 99, to afford a limited T-shaped pressing area (01. This lower face may be roughened or embossed to promote better sealing action between the overlapping portions of the Cellophane sheet. The upper surface of the mandrel 36 can likewise be embossed for the same purpose.

It is desirable to employ suitable means for automatically controlling the temperature of the heater, as for example a thermostatic switch indicated generally at I62. Attachment of the heater to the backing 94 can be by means of three sets of pads 95, which are located to apply pressure near the extremities of the T. ,A further set of pads 9511 located near the center of the T, are normally spaced apart a slight amount, but are brought into contact when suflicient force is applied to the backing to slightly spring the. same within its elastic limit. A mounting of this character has been found desirable in securing even distribution of pressure over the T-shapedsealing area, irrespective of inaccuracies in manufacture or slight warpage of the heated parts.

For supporting the heater structure 32, a forwardly extending arm I03 is provided, which is pivotally attached to the bracket 39 by shaft IN. The forward end of arm N33 has a pivotal connection IIlB with the heater backing 94. A, tension spring I01 serves as an effective counterbalance.

In order to swing the heater structure 94 downwardly and upwardly with respect to the table ID in properly timed sequence with other functions, actuating means operatively connected to shaf I4 is provided as follows: The rear part of arm IIJ3 carries a depending arm I38 (Figs. 9 and 10). Slidably carried by the shaft III, on opposite sides of the cross-head M, are the collars I39 and Ill. These collars are connected together at a spaced distance apart, by the bars H2. The upper co1 lar I38 has a pivotal connection I I3 with a pair of links I I4, which in turn have a pivotal connection IIE with the lower end of arm IilB. Upon the forward side of collar Hi9 there is a lever I ll, having a fixed fulcrum IIS to bracket 23, and connected to the collar I09 by links IZI. The forward end of lever I I1 is provided with an adjustable pin I22 adapted ping surface I23 on the underside of the table IE1. Thus, rotation of lever I H in a counter-clockwise direction, as viewed in Fig. 10, is definitely limited, although the precise limit at which the lever is stopped can be adjusted.

With the arrangement described for connecting arm I33 to the shaft Id, when the shaft I4 is in the position shown in Fig. 9, cross-head H is adjacent the upper collar IE9, both of the links H4 and iii! are swung upwardly, and lever fl? is swung downwardly; As shaft It moves downwardly, collars Hi9 and I I remain stationary until the cross-head II contacts with the upper surface of collar III. Thereafter, further down ward movement of shaft Id causes collars I09 and III to be likewise carried downwardly, with the result that arm I33 and the forwardly extending arm I33 are rotated in a clockwise direction, to lower the heater structure 92. During the final movement of shaft I4 to the lowermost limit of its travel, links H l and. I2! passthrough dead center positions, substantially as shown in 10, thus locking the heater structure 9?. against the lowered mandrel For the first part of the upward return travel of shaft I4, collars I59 and I I i remain stationary until cross-head has come into contact with the lower face of collar I03. Such lost motion affords sufficient time for completion of the sealing operation. Thereafter, both of the collars are moved upwardly, tobreak the toggle established by links II and Iii, and thereafter these collars move upwardly under the urge of tension spring Id'L'to swing arm its in a counter-clockwise direction and thus again elevate the heater structure t2. v'li c obviate upward movement of the heater structure 32 at too rap a rate, a suitable frictioning device is provided, such as a shock absorber I23 of the type employed for automotive purposes. The body of this shock absorber is mounted uponbracket 23, while the to engage a bolt or like stopoperating rod I21 has a pin and slot connection I28 with the lower collar I I I.

In the preceding description it has been pointed out that when the machine is operating, a sheet of material such as Cellophane is placed upon the table, and, following lowering of mandrel 36, the side and forward margins of the paper are folded over the side and end edges of the mandrel. It may be further pointed out at this time that following such operation, and following folding and gripping of the forward folded margin by the device 13, the heater structure 92 is lowered to bring the T-shaped area IBI into tight engagement with the overlapping edges of the side margins and also with the folded bottom of the bag. Following such a sealing operation, the device 13 heater structure starts to elevate, and the side folding members 44a and Nb are retracted. The mandrel 36, which now carries the finished bag formed about it, is then raised to the elevated position shown in Fig. 9.

In some instances the bag may cling to the mandrel, making it diflicult for the operator to effect rapid removal. Therefore, to obviate this difficulty and for other reasons, I prefer to employ an air jet directed toward the open end of the bag and upon the upper side of the mandrel. A suitable means for this purpose is illustrated in Fig. 1, taken in conjunction with Fig. 3. Thus, mounted adjacent the rear end of the mandrel 3B are the air discharge nozzles Iiil. These nozzles I3! connect to a common air supply pipe I32, which in turn leads to a suitable supply of air under pressure. For example, I have indicated an air pump or blower I33, driven by the electric motor I2 and connected to pipe I32 through the control valve I3 1. Valve I34 can be arranged to be tripped open by cam I36, carried upon the onerevolution clutch Il. Thus, at the completion of each revolution of the crank disc I3, valve I34 is momentarily tripped to open position, to permit a blast of air to be discharged through nozzles I3 I. Since the blast of air is directed towards the open end of the formed bag and upon the upper side of the mandrel 35, it serves to loosen the bag with respect to the mandrel and thus facilitate removal of the bag. It also serves to cool the mandrel and to rapidly cool and set the seal.

Operation of the machine can now be reviewed in entirety, as follows: Assuming that the motor I2 is in operation, the operator places upon the table a sheet of the material from which the bag is to be formed, substantially as shown in Fig. -6, utilizing the guides 29 and 33 and the guide pins 35 to effect proper centralization. When finally positioned, the forward edge of the paper extends somewhat beyond the forward edge 36b of the mandrel 3b, to afford sufficient material to form a forward margin 23b for folding in forming the bottom of the bag. The sheet of material employed is preferably a moistureproof fCellophane, carrying a coating such as will afford a seal when overlapping portions of the Cellophane are heated and pressed together. After pro-per positioning of the sheet of Cellophane, the operator depresses foot lever 2| to trip the'clutch IT and thus start shaft I4 downwardly in the first part of its cyclic reciprocation. Initial downward movement of shaft I4 causesa lowering of pins 42, wi th a consequent dropping of mandrel 36 upon the sheet. Further downward movement of shaft Id brings roller 3311 (Fig. '7) into engagement with the cam surface portion 2110f lever 41b, to cause this lever to swingin a counter-clockwise direction, as viewed is released, the

in Fig. 7, and to cause folding member 44b to slide inwardly over the mandrel 36. Such movement serves to fold the side margin 28a of the sheet of material over the corresponding side edge 36a of the mandrel. Such inward movement of the folding member 44b likewise causes inward movement of the end fold-line retaining member 62b. For a short interval, while roller 52b is engaging cam surface 3b, both members 44b and 62b remain stationary. During this interval, folding member 44a is advanced over the mandrel 36 by virtue of the engagement of roller 53a-with cam portion 2a of lever 41a, and the end retaining member 62a likewise moves inwardly. Because of the leverage afforded by levers 68, the two end members 62a and 62b have their inner ends in relatively close proximity as compared with the inner edges of members 44a and 44b, and while in such position they remain substantially stationary for a short interval, while rollers 53a and 53b are advancing over cam surfaces 3a and 3b (which are now substantially vertical). During this interval, roller 86 passes below the lower extremity of cam surface 88, whereby movement of rod 80 causes bar 14 to be elevated and transposed to substantially the position shown in dotted lines in Fig. 4. Because of this operation the projecting end 28b is folded over the end members 62a and 621), the forward edges of these members defining the fold line for the bottom of the bag and also serving to retain the folded side margins flat upon the mandrel, thereby insuring properly folded corners and the absence of wrinkles.

Further and continued downward movement of the cross-head 4| causes the side folding members 44b and 44a to be successively moved to their final limits, by virtue of engagement of rollers 53a and 53b with cam shoulders 4a and 4b. Such final inward movement is accompanied by escapement of trip lever 68 over pins I2, with a springing-back of the end members 62b and 62a. Immediately preceding this operation, roller 86 passes below the extremity of cam surface 89, to cause bar T4 to be lowered in gripping engagement with the folded end margin 28!) and with the members 62a and 62b. Retraction of members 6211 and 62b permits the bar I4 to press the folded end margin directly against the mandrel.

Immediately prior to gripping movement of bar 14, cross-head 4| causes collars I89 and I II to be lowered, to swing down the heater 92. When cross-head 4| has reached its lowermost limit, as illustrated in Fig. 10, the toggle established by links H4 and I2I is set, and the lower surface IIII of the heater is forced with considerable pressure against the T-shaped area formed by the overlapping edges of the side margin and also the overlap between the end margin 28b and the side margins. A relatively short duration of time for such engagement of heater surface |I with the overlapping portions of the Cellophane will suflice for a sealing operation.

As shaft I4 now starts its upward movement, it first engages cam finger 81, to release the bar 14, and then engagement with collar I69 causes breakage of the toggle established by links H4 and I2], to permit elevation of the heater 92 under the urge of tension spring I61. Continued upward movement of shaft I4 causes levers 41a and 41b to be swung back to the positions illustrated in Fig. 7, by virtue of engagement of roller 530. with cam surface I2, and roller 53b with cam surface lb, to retract the side rolling members 44a and 44b. Final movement of shaft I4 causes pins 42 to elevate the mandrel 36, which now has the bag formed about it, and upon elevation of the mandrel a jet of air is discharged from nozzles I3| to tend to release the bag with respect to the mandrel.

In the foregoing description I have referred principally to the making of a simple bag from Cellophane, having a substantially rectangular contour when flattened. It is possible, however, to form the bag about an article, thus dispensing with the operation of placing articles in the bags after they are formed. Thus, as shown in Fig. 11, the top of the table can be provided with a pocket or recess I4|, sufficient in dimension to accommodate the article I42. Provided the recess MI is not too deep to cause undue wrinkling of the Cellophane sheet, the machine will now operate the same as has been previously described, with the exception, however, that the bag will be formed directly about the article. It is apparent that such a modified machine can be employed in many instances, as for example in wrapping laundered articles, or for like application where the article is not too bulky.

The machine can be easily adapted to form bags of varying sizes. If a shorter bag is desired, without change in width, shorter sheets ar employed, and the gauge blocks 29 are adjusted accordingly. If the width of the bags is to be varied, a narrower mandrel is substituted for the mandrel 36, narrower sheets are employed, and the gauge bars 30 are readjusted.

In some instances where a stiffer bag is desired, or where a less expensive grad of Cellophane is employed, a liner of paper can be used in addition to the Cellophane sheet. In such instances the paper liner, somewhat greater in width than the width of the mandrel 36, is superposed over the Cellophane, in introducing the same into th machine. Thus in the formation of the bag, the side margins of the liner are folded, and when the bag is completed. the liner affords considerable stiffness and strength. The edges of this liner can be interposed in the seal between the folded side and end margins of th Cellophane, thus in eifect forming a single unit consisting of a Cellophane bag joined to an inner paper bag.

The modification illustrated in Figs. 14 to 1'7, inclusive, is deemed superior, particularly with respect to the mechanisms afforded for operation of the side folding members 44a and 44b, and for operating the fold-line retaining members 62a and 62?). Thus, referring particularly to the parts serving to correlate movements of members 44a and 62a, members 62a carries a pin I5| (Fig. 15), which extends through a slot I58 formed in one end of a lever I52. This ever is fulcrumed to the table I0 by pivot I53, and its rear end is connected to a toggle-spring assembly I54. This assembly consists of a plunger I56, having a pivotal connection I51 to' the rear end of lever I52, and slidably carried by a fixed bracket I58. A compression spring I59 has its one end bearing upon bracket I53, and its other end bearing upon a washer 6| formed as a col-- lar on plunger I56. Thus spring I59 serves to urge the lever I52 in either one of two directions, past an intermediate dead center position.

Near the forward end of folding member 44a there is an L-shaped extension arm I62, the forward end portion I63 of which is provided with an aperture I64. In the position of the parts illustrated in Figs. 14 and 15, the upper projecting end I65 of pivot pin I5I' extends into aperture I64, and therefore inward movement of the folding member 44a causes the corresponding member 62a to move inwardly in unison with the same. Mounted on the forward edge of the table I there is a plate I65, the upper edge of which underlies the path of movement of the forward end portion I63 of arm I62. Near the inner end of plate I56 its upper edge is provided with a cam portion I68 which, when engaged by the arm portion I63, causes this arm portion to be lifted free of the pin II. Not in this connection that the edges of arm portion I53 are bevelled, as indicated at I69, so that one of these bevelled edges engages and rides over a correspondingly bevelled shoulder afforded by cam portion I68. Likewise note that arm I62 affords some resilience, so that while portion I63 can be sprung upwardly, it is normally urged towards member 62a. Connecting parts similar to those described above for members 44a and 62a are likewise provided for members 44b and 62b, and therefore such parts have been designated by like numerals in the drawings.

The cam levers for effecting operation of the folding members 44a and 441) have likewise been modified, and additional cam elements have been associated with the same for effecting actuation of levers I52 to retract members 6221 and 62?), while the folding members 4411 and 44b remain in their projected positions. Thus; referring to Fig. 16, simplifiedcamlevers I1Ia and I1Ib are provided, which have surfaces Ia and lb similar to the levers 41a and 41b of Fig. 7, but which have their lower arms HM and H211 provided with simple linear surfaces 6a and 6b. The upper endsof these levers I1Ia and I1Ib are connected'to the side folding members 44a and 44b in a manner similar to the connections previously described with respect to Fig. '7, for the levers 41a and 41b in the first described modification. The pivot pins 48 likewise pivotally support cam levers I13a and I131), which have their upper ends connected by links I14 to the rear end portions of levers I52. The lower portions I16a'and I16b of levers I13a and I13b extend toward each other, and, for certain operating positions, are in the paths of movement of rollers 53a and 5311.

Operation of the modification described above can be briefly outlined as follows: Assuming that a sheet of Cellophane or like material 28 has been placed upon the table in properly centered position, and that the operator has depressed the foot lever 2|, initial downward movement of the main vertical shaft I4 causes a lowering of the mandrel 36, as previously described. At this time the mandrel 36 lies upon the sheet 28, substantially as illustrated in Fig. 15. Further downward movement of shaft I4 causes the rollers 53a and 5%, carried by the cross-head Al, to engage the lower arm portions H211 and I12b of levers Illa and I1Ib, to cause these levers to successively rotate in opposite directions, thus moving the folding members 44a and 4417' over the mandrel 36. Since at the beginning of this inward movement of the side folding members pin I-5I is engaged in the aperture l6fi (Fig. 15), the end fold-line retaining members 62a and'62b are likewise moved inwardly over the forward edge portion of the mandrel 36, in unison with the folding members 44a and Nb. Such movement of members 62a and 621) also causes swinging of lever I52, thereby carrying motion through links I14, to swing the cam levers I13a an I13b. Just before. the side folding members 4411 and 4411 have reached the limit of their inward movement, member I63 strikes the cam portion I68 and is thereby released with respect to pin I5I. At this time levers I52 will have passed their dead center positions with respect to the toggles established by plungers I56, and therefore, by virtue of the bias afforded by compression springs I59, further movement of levers I52 occurs to project the fold-line retaining members 6211 and 621) until their inner ends are substantially in contact. As has been previously explained with respect to Figs. 1 to 13 inclusive, further downward movement of shaft I4 causes the folding and gripping device 13 to be elevated and transposed over the blades 62a and 62b, to generally fold over the projecting bottom margin of the Cellophane. The shaft I4 is now moved downwardly sufficiently far to bring the cam rollers 53a and 5312 into contact with the projecting arms I16a andI16b of the levers I13a and H31). In this connection, note that at this time arm. I16a occupies a position to the right of the position illustrated in Fig. 16, while arm I56b is in a position to the left of that illustrated in this view. Therefore continued downward movement of shaft I4 causes levers I13a and I131: to be rotated back into the positions illustrated in Fig. 16, and during such movement the springtoggle assemblies I54 are again moved past dead center positions, after which the forward ends of levers I52 are rapidly swung outwardly and members 62a and 62!) are rapidly moved to retracted positions. Immediately prior to retraction of members 6211 and 62b the folding and gripping device 13 moves down into engagement with these members, whereby retraction of the same permits bar 14 to press the folded end margin directly on the mandrel. The remaining operations of the machine now occur substantially as described with respect to Figs. 1 to 13 inclusive.

I claim:

1. In a machine of the character described for the making of bags from sheet material like Cellophane, a frame formed to afford a working table, a plate-like mandrel movably secured to the table whereby it may swing vertically with respect to the upper surface of the table, a heater overlying both the upper surface of the table and the mandrel, said heater being hmgedly carried by the frame whereby the mandrel is arranged to permit a sheet of said material to be placed between it and the upper surface of the table, means for folding projecting side margins of the sheet over the side edges of the mandrel, means for folding a projecting forward end margin of the sheet over the forward edge of the mandrel, and actuating means serving to effect cyclic operation of said folding means and serving to force said heater downwardly upon the mandrel after a folding operation.

2. In a machine for making paper bags from sheet material like Cellophane, a frame forming a working table, a plate-like mandrel disposed above the upper surface of the table and movably connected to the frame whereby a sheet of material to form a bag can be placed between the upper surface of the table and the mandrel, means for folding projecting side margins of the sheet over the side edges of the mandrel, means for folding a projecting end margin of the sheet over one end edge of the mandrel, a heater overlying the mandrel and movably connected to the frame, a vertical reciprocal shaft carried by the frame, motive means for effecting cyclic reciprocation of said shaft, and mechanism serving to connect said shaft with both said folding means and said heater, whereby upon reciprocation of said shaft said folding means and said heater are operated in sequence.

3. In a machine for the manufacture of bags from sheet material like Cellophane, a frame forming a working table, a mandrel oveflying the upper surface of the table, means forming a pivotal connection between the rear end of the mandrel and the frame, whereby the mandrel may swing in a vertical plane with respect to the upper surface of the table and whereby a sheet of material to form a bag can be placed between the mandrel and the upper surface of the table,.means for foldingprojecting side margins of the sheet of material over the side edges of the mandrel, means for folding a projecting end margin of the sheet over the forward end edge of the mandrel, a heater overlying both the table and the mandrel, means forming a pivotal mounting for the heater with respect to the frame whereby the heater can be swung downwardly on top of the mandrel, a vertical reciprocal operating shaft carried by the frame, mechanism connecting said shaft with said firstmentioned folding means to effect cyclic operation of the same as the shaft is reciprocated, mechanism connecting said second-mentioned folding means with said shaft to likewise cause cyclic operation of the same as the shaft is reciprocated, mechanism connecting said shaft with said heater to cyclically lower and raise the heater with respect to the table for a pressing and sealing operation, and mechanism connecting the shaft to the mandrel to cause raising and lowering of the mandrel.

4. In a machine for making paper bags, a frame forming a working table, a plate-like mandrel overlying the upper surface of the table and connected to the frame for vertical movement relative thereto, whereby a sheet of paper to be folded can be placed between the mandrel and the upper surface of the table, a heater overlying the table and connected to the frame for vertical movement, and means incorporating toggle linkage for releasably clamping the heater down upon the mandrel.

5. In a machine for making paper bags, a frame forming a Working table, a plate-like mandrel overlying the upper surface of the table and connected to the frame for vertical movement relative thereto, whereby a sheet of paper to be folded can be placed between the mandrel and the upper surface of the table, a heater overlying the table and connected to the frame for vertical movement, a reciprocating rod, and means incorporating a toggle linkage for releasably clamping the heater down upon the mandrel upon movement of the rod in one direction and for tripping the toggle linkage to enable raising of the heater when the rod is moved in the opposite direction.

6. In a machine for making paper bags, a frame forming a Working table, a plate-like mandrel overlying the upper surface of the table and connected to the frame for vertical movement relative thereto, whereby a sheet of paper to be folded can be placed between the mandrel and the upper surface of the table, a heater overlying the table and connected to the frame for vertical movement, counterbalancing means serving to urge the heater towards an elevated position with respect to the table, a reciprocating member, and means incorporating a toggle linkage for releasably clamping the heater down upon the mandrel upon movement of said member in one direction and. for tripping the toggle linkage to enable raising of the heater when said member is moved in an opposite direction.

7. In a machine for making paper bags from sheet material like Cellophane, a frame forming a Working table, a plate like mandrel movably mounted with respect to the table whereby -a sheet of said material may be placed between said mandrel and the upper surface of the table, means for folding projecting side margins of the sheet over the side edges of the mandrel, means for folding a projecting end margin of the sheet over the forward end edge of the mandrel, retractable fold line retaining means associated with the forward end edge of the mandrel and adapted to be interposed within the last mentioned fold, a sealing heater pivotally carried above the mandrel, a common source of power for operating said folding means, said retractable fold line retaining means, and said heater, and mechanism connecting the source of power with said folding means, the fold line retaining means, and the heater, said mechanism afiording a cycle of operation in which the first named folding means is caused to fold the projecting side margins of the sheet over the side edges of the mandrel to afford a longitudinal overlap, the fold line retaining means is moved to establish a line of fold relatively close to the forward end of the mandrel, the end folding means is actuated to fold over the end margin of the sheet over said end edge of the mandrel and the fold line retaining means, the fold line retaining means is actuated to retract the same from the fold, and the heater is then pressed down upon both the longitudinal overlap and the end fold, to form both longitudinal and bottom seals.

8. In a machine as in claim 7 in which the fold line retaining means includes a pair of strips, means actuated from the source of power to move the strips toward each other over the mandrel to provide a line of fold, and means for effecting retraction of the strips away from each other prior to engagement of the sealing heater.

RENE J. GAUBERT.

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