US2749691A

US2749691A - Commodity packaging machine

Info

Publication number: US2749691A
Application number: US199047A
Authority: US
Inventors: Harold P Lewis
Original assignee: PAK RAPID Inc
Current assignee: PAK RAPID Inc; PAK-RAPID Inc
Priority date: 1950-12-04
Filing date: 1950-12-04
Publication date: 1956-06-12
Anticipated expiration: 1973-06-12

Description

June 12, 1956 H P. LEWIS COMMODITY PACKAGING MACHINE 4 Sheets-Sheet 1 Filed D90. 4, 1950 //MMIN%EN OR BY r I ATTORNEYS June 12, 1956 H. P. LEWIS 2,749,691

COMMODITY PACKAGING MACHINE Filed Dec. 4, 1950 4 Sheets-Sheet 2 I II:

2 W) ATTORNEY5 June 12. 1956 H. P. LEWIS 2,749,691

COMMODITY PACKAGING MACHINE Filed Dec. 4, 1950 4 Sheets-Sheet 3 INIENTOR flux: P. km.

0 lom rm TTORNEYS June 12, 1956 H P. LEWIS COMMODITY PACKAGING MACHINE Filed Dec. 4, 1950 ATTORN EYj United States Patent CGMIVIODITY PACKAGING MACHINE Harold P. Lewis, Newtown, Pa., assignor to Park-Rapid Inc, Philadelphia, Pa., a corporation of Pennsylvama Application December 4, 1950, Serial No. 199,047

1 Claim. (Gl. 53-480) This invention relates to packaging machines of the type disclosed in my co-pending application Serial No. 155,620 filed April 13, 1950, now Patent No. 2,626,494, issued January 27, 1953, and consists in improvements in various parts of the machine whereby additional advantages can be obtained.

The primary object of my invention is the provision of a packaging machine enabling the forming of packets or bags of a large variety of sizes both as to length and width.

Another object-of my invention is the provision in a packaging machine of the character described of simple mechanism for controlling the package cut-off mechanism of the machine to effect cut-off of the packages one after the other, or in strips containing a plurality of packages.

A further object of my invention is the provision in a packaging machine of the character described of means enabling a double package having a small and large compartment to be formed.

A more specific object of my invention is the provision of a driving mechanism for imparting step by step drive to the crimping and sealing rolls or rotors of the machine which is adjustable to vary the magnitude of the steps and which also provides a slight period of dwell between steps.

How the foregoing and other objects and advantages are attained will appear more fully from the following description, referring to the accompanying drawing, in which Fig. 1 is a front elevational view of a machine constructed in accordance with my invention;

Fig. 2 is an enlarged rear elevational view of the machine as indicated by the line 2-2 of Fig. 3;

Fig. 3 is a plan section taken on the line 3-3 of Fig. 2;

Fig. 4 is a cross sectional view taken on the line 4-4 of Fig. 2;

Fig. 5 is a fragmentary cross section taken on the line 55 of Fig. 2;

Fig. 6 is a sectional view of a cutter or knife employed 1 in the machine, the section being taken on the line 66 of Fig. 4 and the knife being shown in its out ofi position; Fig. 7 is a cross section of one of the crimping and sealing rolls;

Fig. 8 is a plan section taken on the line 88 of Fig. 7;

Fig. 9 is a cross section similar to Fig. 7 of another crimping and sealing roll; and

Fig. 10 is a fragmentary plan view of Fig. 2 as indicated by the line 10-10.

My improved machine comprises in general a supporting frame S, reels carrying rolls of packaging material P, such as paper, cellophane or the like, crimping and sealing rolls R and R; knife or cutter mechanism K,

drive mechanism for the crimping and sealing roll R indicated as a whole by the reference letter D, and a clutch C for controlling the knife or cutter mechanism K.

The supporting frame S includes a main upright supice reels of paper P; a top plate 12; a front supporting plate 13; a base plate 14; and web plates 15.

The crimping and sealing rolls or rotors R and R are secured to parallel cross shafts 16 and 16' respectively which are mounted in the supporting

plates

10 and 13 of the frame S by means of journal blocks 17 and 17 mounted in

longitudinal slots

18 and 18 in the

plates

10 and 13.

As an aid in correctly positioning the rolls when the machine is set up for operation, I have provided aligned

holes

19 and 19 in the plates 10 and 13 (see Figures 1, 2 and 4) adapted to receive a positioning pin extending crosswise of the machine against which the drive roll R is pushed. These holes are so located that the peripheral face of the roll falls in the middle plane of the wedge shaped article receiving pocket W as viewed in Fig. 2. After the drive roll is so positioned it is secured in place by means of lock screws 20 which pass through slots 21 in the brackets 22 carried by the journal blocks 17 and which secure the brackets to the frame plates it) and 13. The positioning pin is then removed and the driven roll R is brought into driving contact with the drive roll R. Referring to Fig. 1, this driven roll R is spring urged into driving contact with the drive roll R by means of spring 23 anchored at one end to a fixed pin 24 and attached at the other end to an arm 25 pivoted on the frame at 26 and having a rod 27 adjustably secured thereto by nuts 28, which rod extends into engagement with the journal block 17' at 29. A similar spring and pivoted arm arrangement is employed at the other journal block 17' of the roll R as will be seen in Fig. 2.

The rolls R and R are of like construction and each comprises a pair of circular end plates or flanges 30, a central hub 31 and radially disposed transverse or cross sealing members 32, the end plates and transverse sealing members on one roll being opposed to the like members on the other roll. In Figures 2, 4, 7 and 8 I have shown the rolls as having three such cross seal members but it will be clear from description hereinafter appearing that my machine is adapted with simple adjustment to employ rolls having a different number of cross seal members for forming packages of different lengths.

The periphery of each end plate 30 and the outer edge faces of the cross seal member 32 are crimped or serrated as indicated at 33 and 34 respectively.

The drive mechanism D for the rolls is adapted to impart step by step rotary movement thereto and comprises a drive wheel or sprocket 35 mounted on a stud 36, receiving drive, as by means of a chain 37 and sprocket 38, from a source of power such as the motor operated gear unit indicated at 39, a crank pin 40 associated with the sprocket 35, a connecting link 41 between the crank pin 40 and a rocker arm 42 mounted for free rocking movement on the shaft 16 of the roll R, a pawl 43 pivotally carried by the rocker arm 42, a ratchet wheel 44 secured on the shaft 16 and a spring 45 for maintaining ratchet engagement of the pawl and ratchet wheel.

It is to be observed that the crank pin 40 is carried by a bar 46 which slidably fits a groove 47 in a plate 48 secured by screws 49 to the face of the sprocket 35. By this means the throw of the crank and consequently the throw or stroke of the pawl 43 can be adjusted to impart the desired amount of rotative movement to the roll R for each revolution of the crank. When the adjustment has been made the bar 46 is locked in place by means of the clamping screws 50.

Referring particularly to Figure 2 it is pointed out that the crank has been adjusted to a throw which will impart one third of a revolution to the rolls R and R with each revolution of the crank and that as it rotates in the direction of the arrow from the position shown the pawl 43 will ratchet over the ratchet teeth and the rolls will remain or dwell for a short time in the position shown in which a pair of cross seal members 32 are in registry and forming a cross seal. This period of dwell is of importance for reasons which will be explained later. As the crank continues to rotate the ratchet is picked up by the pawl and rotated to bring the next pair of cross seal members into registry. Thus the rolls are rotated in successive steps of one third their circumference with a pair of cross seal members 32 being brought into registry with each step.

'Referring now to the feeding of the packaging material through the machine it will be seen from Figure 1 that the material P is fed from the reels inwardly and over guide '

rolls

51 and 52 and then downwardly between the crimping and sealing rolls. As the material feeds downwardly between the rolls crimped side seals 53 are formed by the end plates 30 of the rolls and cross seals 54 are formed by cross seal members 32. The grip of the rolls causes feed of the material through the machine and since the drive mechanism D imparts rotative movement to the rolls in steps of one third revolution, the feed of material for each step will be equal in length to one third of the circumference of the rolls. It willthus be seen that since a cross seal is made with each such step the length of package formed will be equal to one third of the circumference of the. rolls.

Articles or material to be packaged are introduced into the wedge shaped pocket W located above the point where the cross seal is made. The sides of the pocket are formed by the downwardly and inwardly inclining stretches 55 of the packaging material and the ends of the pockets are formed by downwardly projecting triangular or wedge shaped plates 56 supported from the top plate 12 of the machine frame. As will be seen from Figures 4 and these end plates, 56 are positioned somewhat in from the inner faces of the end seal plates 30 of the rolls to prevent articles or material being packaged from getting between opposed end seal plates. The articles or material to be packaged are fed into the machine when the rolls are in cross seal forming position and the feed may be by hand or by well known feeding means. The period of dwell when the rolls are in cross seal forming position is particularly advantageous when the articles to be packaged are fed to the machine manually as it gives the operator a brief pause during which the article can be. dropped into position between the sealing rolls.

In order to form packages of different widths in the machine, packaging material of the desired width is employed and crimping and sealing rolls of corresponding width are secured on. the

roll shafts

16 and 16 and the end plates 56 of the pocket W are adjusted to suit the width. of rolls employed. In order to provide this adjustment the end plates 56 are adjustably mounted in a plate 57 secured to the top plate 12 of the machine frame. The plate 57 fits over a feed opening 58 in the top plate 12 and is provided with an elongated feed slot 59 through which the pocket end plates 56 project downwardly. Clamp members 60 are provided at the top of the end plates for clamping them to the slotted plate 57 in their adjusted position lengthwise of the slot. To prevent material during feeding, from falling through the end portions of the feed slot 59 when the end plates are adjusted inwardly for a narrow bag, outwardly extending wings 61 carried by the clamp members 60 are provided to cover these end portions of the feed slot.

Referring now to the knife mechanism K this comprises a rotary knife 62 and a stationary blade 63, carried by a. fixed support 63a secured to the machine frame, the knife being shown in cut off position in Figure'l and in Figure 2 in the position it is in when a cross seal is being formed. The knife 62 is secured to a sleeve 64 (see Figure 4) rotatably mounted by means of

end bearings

65, 65 on a hollow stud 66 fixedly secured to the upright frame member 10. The sleeve 64 receives its drive from a shaft 67 extending through the hollow stud 66 for shear pin connection with the drive sprocket 38. The shaft 67 is drivingly connected to the sleeve 64 through the medium of the clutch C and an adjusting member 68.

Assuming now that packages of equal length are being formed as shown in Figure 2 then the clutch C is moved into its engaging position as shown in Figure 4 and the knife will rotate continuously to cut off package after package substantially centrally of the transverse seal, it being noted that the drive sprocket 38 of the knife and the drive sprocket 35 of the crank are of the same size so that a cut-off is made with each revolution of the crank. It is to be remembered, however, that each revolution of the crank 35 effects only a partial revolution of the roll R through the pawl and ratchet mechanism. The sprocket 38 of the knife therefor makes a complete revolution for every predetermined partial revolution of the roll R and the knife 62 is therefore made angularly adjustable with respect to the sleeve 64 and sprocket 35 to facilitate proper relative positioning of the knife for cutting off packages of different lengths. In setting up the machine for the particular length of package shown in Figs. 1, 2 and 4 the locking screws 69 fitting the arcuate slots of the knife adjusting member 68 are loosened and the knife sleeve is rotated to bring the knife into cutting relation with the stationary blade 63 as shown in Figure 1, when the cross seal members are in the position shown in Figure l and indicated by the dot and dash line 32a in Figure 2. The locking screws 69 are then tightened. It will thus be seen that the previously formed package is cut off before the top cross seal of the next package is formed. By means of this adjustment the knife can be set to cut off at the proper time for any length of bag which can be made on the machine. The completed packages are discharged from the machine by means of a discharge chute 83as illustrated in Figure 1.

I also contemplate the provision of strips containing a plurality of connected packages and this is accomplished by operating the clutch control lever 70 to release the clutch C to stop the knife while the desired number of packages are being formed and then operating the control lever to engage the clutch to effect cutting operation of the knife after the last package of the strip has been formed. This operation of the control lever can be accomplished manually or by suitable automatic timing mechanism such as a timed electro-magnet connected to the control lever by an operating rod 71.

Referring now to Figures 7 and 8 itis to be noted that the hub 31 of the rolls is provided with six longitudinally extending grooves 72 evenly spaced circumferentially of the hub for receiving cross seal members although only three cross. seal members 32 are shown in place to form packages of the length mentioned above. When it is desired to form shorter packages, cross seal members are employed in all of the grooves. The cross seal members are readily insertable in the grooves and are secured in place as by means of screws 73 securing them to the end plate 30. The end plates are secured to the hub 31 by means of screws 74 and the assembled rolls are secured to the shafts as by means of set screws 75.

By employing rolls having grooves of various spacing and by employing cross seal members either in all of the grooves or only in some of the grooves I am enabled to produce packages of a great variety of lengths with only a few different rolls. For example in Figure 9 I have shown another roll having eight grooves 76. By employing four cross seal members in such roll packages of one length are formed and by employing eight cross seal members packages of shorter length are formed.

In changing over from forming packages of one length to forming packages of another length the throw of the a faaco i crank 40 must be altered to change the magnitude of the steps of rotation imparted to the rolls by the ratchet drive mechanism D to correspond to the spacing of the cross seal members of the rolls employed. This is accomplished by adjusting the crank carrying bar 46 in the manner described above. For example if the machine as set up in Figure 2 is to be changed over to form packages of one half the length of those being formed, three cross seal members are added to the rolls and the crank bar 46 is adjusted inwardly to a point where the amount of rotative movement imparted by the ratchet drive corresponds to the spacing of the cross seal members.

In addition to forming packages of various lengths as above described, I also contemplate forming what may be termed a double compartment package having a large main compartment and a smaller auxiliary compartment. Such packages have many uses in the packaging trade, one example being in the packaging of candies with which a toy or token of some kind is to be included which for one reason or another should not be packed directly in with the candy. By employing a double compartment package the candy can be packaged in the larger main compartment and the toy or token in the smaller auxiliary compartment.

Such packages can be formed in my machine with the same rolls that produce packages of equal length by dropping out certain cross seal members. For example by removing one of the three cross seal members of the rolls of Figure 7 a double compartment package will be formed with the main compartment double the length of the auxiliary compartment. The setting of the ratchet drive mechanism will remain the same as before but the stroke at the removed cross seal member will be an idle one, i. e., no cross seal will be formed at this stroke. Since the two compartments are to remain connected, cut off is made at every other cross seal and this is accomplished by timed control of the knife clutch C in the manner described above in connection with forming strips composed of a plurality of packets.

In order to obtain an even greater variety of sizes of packages the

slots

18 and 18, in which the journal blocks 16 and 16 of the rolls are mounted, extend Well inwardly toward the center of the machine so that rolls of smaller diameter than those shown in the drawings can be employed. The only adjustments necessary are adjustment of the bracket 22, the rod 27 and the tension of the spring 23. The various results described above are obtainable when employing such smaller rolls by corresponding ratchet drive adjustment, knife adjustment and clutch control.

In order to heat seal the packages I provide electric heating elements 77 in the holes 78 of the rolls. Electric connection of the heating elements to a source of electric current is made by means of a pair of contact rings 79 carried by the roll shafts and fixed contact bars 80 supported from the frame of the machine as shown in Figure 4.

In the embodiment illustrated in the drawing I have shown only the electric heating elements 77 extending through holes '78 in the end flanges 30 and the transverse sealing members 32. In some cases it may be necessary to insert a ring heater in the end flanges in addition to the heaters illustrated. Such ring heaters could be connected in series with the heaters 77 shown.

In connection with the heating of the rolls, it is to be noted that since the transverse seals are cut substantially in the center to form separate packages, the transverse seal should be substantially double the width of the longitudinal seals when formed, in order to have the same width of seal at the top, bottom and edge of the separated packages. This means that the width of the sealing surface of the transverse seal forming members 32 must be substantially double the width of the sealing surface of the longitudinal seal forming flanges 30. Also since the transverse seal is formed clear across the package, it means that there is a considerably greater surface contact between the transverse seal forming members and the packaging material when the transverse seal is formed than there is between the longitudinal seal forming flanges and the packaging material at any time during the formation of the longitudinal seals. As a practical matter, this means that there should be a longer time of application of heat and pressure to the packaging material when the transverse seal is formed than is required in the forming of the longitudinal seal. This is an additional important reason for the provision of the period of dwell when the transverse seals are being formed.

To avoid burning of the seals for example if the heating elements are left on when the machine is idle, the crimping and sealing rolls are adapted to be moved out of sealing contact by means of a pivoted lever 81 having a lug 82 in the engagement with the arm 25 which is connected to the roll journal block.

Another important feature of the drive mechanism I have shown is that the crank drive of the pawl and ratchet mechanism imparts to the heat sealing rollers a smooth, slow, initial acceleration from the position of rest and a smooth, slow, retardation to the position of rest. By this arrangement, since the feed of the packaging material is effected by the rollers, the pulling stress on the material is applied gradually and not by a sudden jerk. This eliminates tearing of the materials which frequently occurs when the rollers are accelerated abruptly and a slow retardation aids in preventing over-running of the packaging material when the rollers are coming to rest.

It will be understood that the apparatus I have disclosed could, with slight modification, be used to seal the margins of a folded single strip of packaging ma terial. In such case there would be need for only one pair of opposed longitudinal seal forming flanges although from the point of view of feed of the strip it would probably be desirable to have opposed gripping rolls at the folded edge of the strip to engage and feed the folded edge through the machine.

I also wish to point out that it is not necessary that the longitudinal seal forming flanges and the transverse seal forming members be mounted on the same shafts. For example, the longitudinal seal forming flanges could be mounted on a shaft in advance of the shaft carrying the transverse seal forming members in the manner illus trated in my co-pending application Serial No. 121,297 filed October 14, 1949, now Patent No. 2,657,510, issued November 3, 1953, or as shown in my Patent No. 2,522,- 682. In such case, since the shafts on which the transverse cross sealing members are mounted are urged towards each other by means of spring 23, it would be necessary to have opposed engaging circular members (corresponding to the circular flanges 30) to prevent the shafts from shifting when the transverse seal members are not in opposed position.

It will be seen from the foregoing that I have provided a packaging machine which with simple adjustments and with the use of certain substitute parts is capable of producing packets of a. great variety of sizes both as to width and length; packets linked together in strips of two or more packets; and double packets having a large and small compartment.

I claim:

In a package forming and sealing machine for heat sealing strips of packaging material, said machine having rotary sealing rolls, each roll having axially spaced circular members for forming edge seals and a plurality of axially extending members for forming cross seals, the improvement comprising: a mounting mechanism for each roll disposed relative to one another to mount the rolls in spaced-apart relation for accommodating the 7 5 feeding strips of material therebetween; adjustable means References Cited in the file of this patent UNITED STATES PATENTS Parkes Nov. 6, Macdonald Feb. 26, Weber Feb. 9, Hutt Jan. 7, Salfisberg June 15, Salfisberg Dec. 28, Vogt May 2, Salfisberg Mar. 5, Ravenscroft Apr. 14, Lewis Sept. 19, Bardsley Feb. 13, Lewis Jan. 27,