US3188781A - Packaging machine - Google Patents

Description

T. H. AQUARIUS ETAL 3,188,781

June 15, 1965 PACKAGING MACHINE 2 Sheets-Sheet 1 Filed Aug. 21, 1962 Fig. 4

IN VEN T UPS 2 meoooew' H- flqvnk Jonmves F Hummus June 15, 1965 T. H. AQUARIUS ETAL PACKAGING MACHINE 2 Sheets-Sheet 2 Filed Aug. 21, 1962 edges of the tube in overlapping relationship.

United States Patent Ofiice 3,188,78l Patented June 15, 1965 This invention relates to packaging machines, and more particularly to such machines which produce individual filled and sealed packages from a tube of heat scalable material.

.In these machines, the heat scalable packaging material is usually supplied in the form of a continuous Web wound upon a supply roll. The web is led from the supply roll around a forming element serving to convert the initially fiat web into a tube with the longitudinal In this condition, the tube surrounds a filling pipe of the machine, and a heated tool cooperates with the filling pipe to fuse the longitudinal edges of the web.

A pair of transverse heated sealing jaws are arranged on either side of the tubular packaging material, the jaws being mounted for movement toward each other, to produce a transverse seal in the tubular material, and away from each other, to release the material after formation of the seal. In addition, when the jaws are in engagement with the tubular material clamped between them, they are movable in a direction parallel to the longitudinal axis of the tube in order to advance the packaging material through the machine. After the jaws separate, they move back in the direction opposite to the direction of advancement of the packaging material to their initial position preparatory to formation of the next transverse seal. Beween each two successive sealing operations, a filling apparatus discharges a quantity of the product being packaged through the filling pipe into the tube. A knife is also provided for severing the tubular material along a line within each of the transverse seals so that in eifect each sealing operation produces the top or final seal for a package already filled, and the bottom or initial seal of a package about to be filled.

' Packaging machines of this general type are well known.

The longitudinal back and forth movements, i.e. movements parallel to the longitudinal axis of the tubular material, of the transverse sealing jaws are brought about by mechanical means of one type or another, and if it is desired to alter the length of the longitudinal stroke of the jaws, it is ordinarily necessary to bring the entire packaging machine to a halt. This is a great disadvantage, because such an alteration of the length of the longitudinal stroke of the transverse sealing elements is required, not only when a package of greater or shorter length is to be produced, but also to compensate for various deviations which occur' during normal operation of the machine. For example, when operating with packaging material of printed character, irregularities in the spacing of the printing along the web may require, on occasion, that the distance through which the material is moved during each advancement be increased or decreased to insure proper orientation of the transverse seals with respect to the printing. Or, due to stretching of the material the transverse seals may be occurring in improper relationship to the printing, and for this reason also variation of the extent of advancement of the tube may be required to restore the desired relationships. In conventional packaging machines of this kind, these adjustments require that the machine as a whole be stopped.

An objective of the present invention is to alleviate this disadvantage by providing means whereby it is possible to alter the extent of the longitudinal movements of the sealing jaws during continued operation of the packaging machine.

Furthermore, in known packaging machines of this character, the introduction of the product to be packaged into the tubular material is mechanically regulated to take place at a definite point in the operating cycle of the packaging machine. This has numerous disadvantages, the chief one being that the speed of operation of the packaging machine is dependent upon the speed with which the product to be packaged can be introduced. Under some circumstances this is quite a limiting factor. Obviously, if an adjustment could be made to vary the particular moment at which the filling apparatus concludes its operation, this disadvantage would be obviated. This is especially true if the particular moment at which the feeding operation is completed can be regulated in accurate dependence upon the nature and quantity of the material, and independently of the operational cycle of the machine.

A further objective of the invention, therefore, is to provide a means for achieving such regulation during continued operation of the machine as a whole.

In achieving one of these objectives, the present invention employs a hydraulic piston-cylinder arrangement for controlling the extent of the longitudinal movements of the transverse sealing jaws, the piston-cylinder arrangement being so constructed that it is capable of varying the longitudinal movements of the sealing jaws by changing the point at which the movements terminate in the direction of advancement of the packaging material, while the point at which the movements terminate in the opposite direction remains constant. This variation is brought about by an adjustment of the stroke of the controlling piston-cylinder arrangement.

In accomplishing the other of the above objectives of the invention, means are provided for actuating the product-feeding hopper or other filling mechanism in such a way that the conclusion of the period of introduction of the product into the tube will be at a definite and predetermined accurate point in the machine cycle, this point of conclusion being variable during continued operation of the machine.

In the accompanying drawings:

FIGURE 1 is a schematic representation of a packaging machine of the type to which this invention relates;

FIGURE 2 is a cross-sectional view-taken along the line 11-11 of FIGURE 1;

FIGURE 3 is an enlarged representation of the sealing jaws shown in FIGURE 1 and designated by the reference character K;

FIGURE 4 is an enlarged fragmentary plan view of the cutting knife;

FIGURE 5 is a face view of a filled and sealed package of the type produced by the packaging machine;

FIGURES 6 and 7 are diagrammatic vertical crosssectional views of an arrangement for hydraulically controlling the longitudinal movements of the sealing jaws in accordance with this invention;

FIGURE 8 is an enlarged fragmentary vertical crosssectional view of an arrangement according to this invention for adjusting the timing of the filling operation; and

FIGURE 9 is a view of FIGURE 8 from the right side of FIGURE 8.

The packaging machine schematically represented in FIGURE 1 is of a conventional type. A housing 1 is provided at the top with a plate 2 mounted in cantilevered fashion. Fastened to the unsupported portion of the latter is a filling pipe 3 which extends through the plate 2 and flares outwardly at its upper end. Also mounted on the plate 2 is a filling apparatus not shown, which may be of any desired or suitable kind, including a hopper 11 adapted.

to contain a measured charge of the product to be packaged.

Beneath the plate 2 a forming element 4 is mounted on.

from this roll, passes over' the guide roller 6, thenc'eto the forming element 4 which causes the sheet to assume the cylinder 18.

a tubular co'ndition surrounding the filling pipe 3. The

overlapping ofthe longitudinal edges of the 'web is indicated at a in FIGURE 2, and a longitudinal heated sealing tool 7 cooperates with the forming tube 3 for intermittently heat sealing successive portions; of the overlap:

ping longitudinal edges, thereby producing a continuous. tube. 1

Beneath the tube 3 two transverse sealing jaws 8 and 9' are mounted. They are movable toward and away from each other i'n'the direction of the double headed arr'owsof FIGURE 1. Additionally, these sealing elements are mov able vertically in a manner hereinafter to be described in greater detail. I

When the jaws 8 and 9 move into engagement with each other (FIGURES 1 and 3), they clamp the tubular packaging material between them,.and the upper regions f and a v f of the jaws create a lower seal c (FIGURE 5.) while the lower'regions ei and e pr oduce an upper transverse.

seal b (FIGURE 5). 1

Simultaneously with the production of the transverse responds to the length of the package to be formed '(FIG-. URE 5 During this period, the tubular material is relationship to the machine housing .1 by means of a hollow rod 16. The piston 15 is centrally bored, so that the interior of the cylinder 86 is in constant communication with the interior of the hollow rod 16. A hose 17 is secured to the outer end of the rod 16, this hose serving to establishcommunication between the interior of the cylinder 86 and the interior of a hydraulic cylinder 18 (FIGURE 7). A piston 19 is movably mounted within Mounted in bearings 22 and 23, fixed to the machine housing 1, is a shaft 21 rotatable on its axis by means of a motor (not shown) A crank 24 is fixed to the lower end of the shaft 21, the outer end of the crank being connected to the piston 19 by means of a connecting rod 25. The

.- articulation betweenthis rod and the crank'24 is a universal joint 26 or its equivalent, and the articulation be tween the lower end of the rod .and the piston 19 is similarly a universal or spherical joint 27 or the like.

As a result of the joints-26 and.27, the [cylinder 18 is free to move not onlywith respect to the piston 19, but also with respect to the'crank24 and the shaft 21. The

', cylinder 18 is's'ecured to a fork 28 which is pivotally' mounted'at-42to themachine housing 1.1 The pivot axis 42 is tangent to the circular path travelled by the outer endof the crank '24 whe'n the shaft 21rotates on its axis. The's'haft 21 is 'providedfwith'aneccentric collar 29,

V adapted to cooperate with a plunger 30 movable within a .30 seals, the jaws 8 and9 move, downwardly and thus pull or advance the tubular-material from the supply r0115 over the guide roll 6 and the forming element 4; The extent of this longitudinal movement of the'jaws 8 and 9 cor.-.

severed'between the two seams by the cutting device 12, i

which may be a knife having a serrated edge as indicated inFIGURE t. v When the jaws reach the. lower end of their longitudinal movement, they separate from each other, and the filled and sealed package atthe bottom, which has by now been severed from the remainderof the tube, fialls away. In open or separated condition, the jaws travel backin the direction opposite to the direction of advancement of'the tubular material to' the upper end of their .longitudinal movement, and during thislperiod a measured'charge of the product to be packaged is'discharged from the ffiilling apparatus and falls through the filling pipe 3 into the tubular material, the bottom end of which is. sealed. For this purpose a slidable closure 10'maybe provided. By. pulling it out of its position in which it closes the bottom end of thehopper 1 1, acharge of the product in the hop-.

per is allowed to fall into the pipe 3. After the jaws'8 1 advance the web isrepeated.

Referring now to FIGURES 6 and 7, the hydraulic mechanism by means of which the longitudinal jaw movements are brought about, will now be described. As will cylinder 31, the plunger 30 being constantly'urged against the eccentric. 29 by the compression spring 32. The cylinder 31 is provided with a-one-way valve 33, through which it communicates with a fluid. supply reservoir 34, and another one-way valve 35 through which it communicates with a conduit 36 leading to the interior of the hollow rod 16 (see FIGURE 6). r v

Cooperating withthe upperend of the cylinder 86 is a lever 37 having a pivot at 38 between its ends, which controls avalve 40 .by means of a connecting rod 39. The valve 40 is mounted in a branch extending from the conduit 36.. and is spring-pressed to a closed position whereby it normally. seals off a pipe 41.1eading back to the supply reservoir 34 (see FIGURE7).v A tension spring 20 is connected at its upper end to the cylinder 86, and at its lower end to a fixed part of the machine housing 1, whereby serving to constantly urge the cylinder 8 6 in a downward direction.

The interiors of the cylinder 86, the hollow tube 16, the connecting hose, 17, thecylinder 18, and the supply reservoir 34 with its conduits 36 and 41, are all filled with liquid.

The movement of the cylinder 86in'an up and down direction, thereby bringing about corresponding up and down movement of the sealing jaws 8 and 9, are brought about by movement of the piston 19 within the cylinder 18 whereby the liquid is introduced into and with- .drawn from, thecylinder 86. Thus, during the downward movement of the piston 19, liquid is moved through V the hose connection-17 into the'c linder 86, thus lifttransverse seals and again pulling the tube downwardly to; y

benoted in the following description, by means of the present invention it is possible to: alter the extent of the vertical movements of the jaws 8 and 9 during continuous operation of the machine' Furthermore,.this variation is brought about by altering the point at which .the

jaws terminate their downward movement, the point at I which their upward movement terminatesremaining con-.

stant.

The jaws S and 9 are mounted on a vertically shiftable elongated cylinder 86, closed at its upper end. This cylinder is mounted in bearings or guides 13 and 14, formed in the housing 1 of the machine- Within fthe cylinder 86 there is a piston 15, which is securely fixed in immovable ingthecylinder 8 6; and during the upward movement of'the. piston. 19, the liquid leaves the cylinder 86 as the latteris drawn downwardly under the action of the spring 20; This spring thusv serves to prevent the creation of reduced pressure within the cylinder 86, and consequently the'upward' movement. of the piston 19 brings about an immediate downward movement of the cylinder 86.

'The movement of the piston 19 with respect to the cylinder 18 isfbrought about. by the cooperation of two factors, namely, the rotation of the shaft 21 and the disposition of the fork'28 and hence the cylinder 18 mounted thereon at an angle to the axis of the shaft 21. This will now'be described indetail. When the shaft 21 rotates, the outer end of the crank 24 moves through a circular path; This causes the connecting rod 25 to sweep'through' a path defining a conical'surface whose apex lies at the point 27 and whose base is defined by the circular path along which the end of the crank 24 travels. If the longitudinal axis of the cylinder 18 coincides with the longitudinal axis of the shaft 21, as shown in FIGURE 7, the conical surface referred to is a rightangled cone, i.e., the axis of the cone is perpendicular to itsbase. In this limiting condition, the piston 19 does not move longitudinally with respect to the cylinder 18, even though the shaft 21 rotates, and as a result the cylinder 86 remains stationary.

Since the cylinder 18 is movable on the pivot axis 42, it is possible for the cylinder to be shifted to one side. It will be readily understood that the conical surface above referred to now becomes an oblique conical surface, i.e., its axis forms an angle other than a right angle with the base of the cone. Whenever the free end of the crank 24 is in a position 180 from that shown in FIGURE 7, the joint 26 lies directly adjacent to the hinge axis 42 (which, as previously pointed out, is tangent to the circular path of movement of the joint 26) and as a result, in this position of the crank the cylinder 18 can be swung into any desired angular disposition without causing movement of the piston 19 within it. When the joint 26 is disposed directly adjacent to the pivot axis 42, it is closest to the cylinder 18, and hence this position corresponds to the lowermost point in the stroke of the piston 19 and to the upper end of the vertical movement of the cylinder 86. It follows therefore that this end of the stroke is fixed and unchangeable, since when the joint 26 is so positioned the piston 19 will always assume the same position within the cylinder 18, regardless of the angular disposition of the latter. On the other hand, the disposition of the point 26 shown in FIGURE 7 corresponds to the uppermost position of the piston 19, and to the lowermost position of the cylinder 86, and these positions are entirely dependent upon the angularity of the cylinder 18. For example, if the cylinder 18 is swung to the oblique position represented by the axis D so that it forms an angle f with the axis of the shaft 21, the piston 19 will move through a stroke S as the shaft 21 rotates. The magnitude of the stroke S varies with the size of the angle In operation, the shaft 21 rotates continuously, one

' most position of the cylinder 18 (and of the sealing jaws 8 and 9), remain constant.

Obviously the angular adjustment of the cylinder 18 can be performed while the packaging machine is running as well as while it is at a standstill. Moreover, this adjustment can be performed either manually or through suitable mechanical linkage. By any appropriate means the cylinder 18 and the fork 28 to which it is attached can be releasably secured in any desired angular disposition.

The purpose of the eccentric collar 29 and its associated elements is to compensate for possible loss of liquid from the interior of the cylinder 86 or the tube 16 and other parts of the system, and thereby maintain the amount of fluid in the system constant. During each complete rotation of the shaft 21, corresponding to a complete up and down movement of the sealing jaws 8 and 9, the eccentric 29 moves the plunger 30 into the cylinder 31 once, the return stroke of the plunger 30 being effected by the spring 32. During the return stroke, liquid is drawn from the reservoir 34 through the valve 33, and just before the cylinder 86 reaches 6 its uppermost position, this liquid is pushed by the plunger 31 through the valve 35 into the conduit 36, thence into the lower end of the hollow tube 16. In order to prevent the cylinder 86 from moving upward too far, under the influence of this excessive liquid fed to its interior, the lever 37 functions to open the valve 40 so that excess liquid introduced through the conduit 36 is allowed to return to the reservoir 34 through the return pipe 41. Thus the upper limit of movement of the cylinder 86 is maintained. Also, the lever 37 functions to hold the cylinder 86 momentarily at its uppermost position, thus making it possible to move the jaws 8 and 9 into engagement, during that instant of time when the cylinder 86 is stationary, without complicating this operation by a simultaneous vertical movement of the jaws.

In FIGURES 8 and 9 an arrangement is shown by means of which the product-feeding operation can be modified to vary the particular instant at which the loading operation is completed. A shaft 50 is continuously rotated by appropriate drive mechanism, e.g., the same driving mechanism that rotates the shaft 21. A wormwheel 51, freely rotatable on the shaft 50, is journaled Within a bearing 52 secured to the machine housing 1. Directly beneath the wormwheel 51 a plate 53 is keyed to the shaft 50 for rotation with the latter. Thus the wormwheel 51 is rotatably supported between the hearing end of the plate 53 and the fixed bearing 52, the latter preventing axial movement of the wormwheel 51.

Two spaced upstanding bearings 54 and 55 are mounted on the upper side of the plate 53 within which a shaft 56 is rotatably journaled. This shaft carries a worm 57 which meshes with the periphery of the wormwheel 51. On the outer side of the upstanding bearing 55, the shaft 56 carries a wormwheel 58. Meshing with the periphery of this wormwheel is a worm 59 mounted on the shaft of a reversible motor 60. This motor is supported upon the plate 53, and current is supplied to the motor through conductors 61 connected to slip-rings 62 supported in insulated relationship upon the shaft 50. Brushes 63 cooperate with the slip-rings 62, and the direction of rotation of the motor shaft is controlled by an appropriate switch or the like (not shown).

The actuation of the filling device, i.e., the actuation of the slidable closure (FIGURE 1) is controlled by a projection 51a formed on the wormwheel 51 and best shown in FIGURE 8. This projection is adapted, in any suitable manner, to bring about the actuation of the filling mechanism at a specific instant during each complete rotation of the shaft 50.

As long as the motor 60 is deenergized, there is no relative movement between the wormwheel 51 and the shaft 50, because the wormwheel 51 is locked in association with the shaft 50 through the worm 57, wormwheel 58, worm 59, motor 60, and plate 53. However, whenever the motor 60 is actuated momentarily in either direction, there is a corresponding slight angular shifting of the wormwheel 51 with respect to the shaft 50. This relative rotation is brought about through the wormwheel 58 and the worm 57. Thus actuation of the motor 60 in one or the other direction effects an angular shifting of the wormwheel 51 (and with it the actuating part 51a), whereby the exact moment that the filling apparatus is actuated, i.e., the exact moment during which the slidable closure 10 of FIGURE 1 is actuated, may be accurately varied relative to the operating cycle of the packaging machine as a whole. This adjustment can be made whether the packaging machine is running or at a standstill. It is contemplated that an adjustment to the approximate setting will be made while the machine is at rest, and that a final more accurate, adjustment will be made after the packaging machine has been put into operation, the fine adjustment being made by actuation of the motor 60 as hereinbefore described.

The invention has been shown and described in preferred form only andbyway of example and many va'ria' tions may be made which will fall within the spirit and scope of the invention. It is understood, therefore, that I the invention is not limited to any specific form or em-' bodiment except insofar as such limitations are set forth in the appended claims. L i

What is claimed is: a a

1. In a packaging machine, means for guiding a tube of heat-sealable packaging material along a vertical down-' ward direction, means for filling the tubefrorn above with a product to be packaged, a pair of transverse sealing jaws movable toward and away from each other to' produce transverse heat seals, in the tube, said jaws being also movable back and forth in a vertical directions to ad-' vance the tube downwardly while they are together and to rise while they are separated, and a hydraulicpistoncylinder system for controllingthe up-and-down movements ofsaid jaws, said system comprising:

a piston element anda cylinder element one of which is positionally fixed and the other movable upand down,

second worrn'mounted on the shaft of said motor and meshing with said second worrnwheel, and meansfor rotating said motor in either direction, whereby when said motor is unenergized said first wormwheel rotates with said shaft'and when saidmotor is'ener'gized said first worrnwheel is rotated with respect to said shaft.

4. A packaging machine as defined in claim 1, in which thev'fixed element of the piston-cylinder system is the piston element; I I I I 1 5. A packaging rachine as defined in claim 4, in which said piston element is hollow and the pressure fiuid is 20: ment in jawraisingdirection is a pivoted lever"encountermeans connecting said jaws to themova'ble element f r actuation thereby, I

yi-eldable means constantly urging said movable'ele ment in jaw-advancing direction, V means-for vlimiting the movement, of the ment in jaw-raising direction, and

an adjustable pumping means for introducing machine operation for'varying the amount of fluid withdrawn from said cylinder to control the extentmovable eleand withdrawing pressure fluid'into said cylinder, said pump ing means being adjustable without interruption of of jaw-advancing movementof said movable elements 2. In a packaging machine, the elements defined in claim 1 including means for controlling the timingsof the operation of said means for filling the tube with a product,

said control means including an element rotatable in timed relation to the sequence of operations of the packaging machine as a whole, and means for altering the timed re-' lationship of-said'rotatable element to'the sequence of operations, said altering means being-so constructed as to be eifective during continued operation of the packaging machine.

a 3. In a packaging machine, the elements defined 'in claim 2 wherein said rotatable element is a first wormwheel, a power driven shaft upon which said wormwheel is rotatably mounted,-a plate keyed to said shaft, a short shaft rotatably mounted on said plate, 'a' first worm rov tatably mounted on said shortshaft and meshing with said first wormwheel, a second wormwheel mounted on said short shaft, a reversible motor mounted on said plate, a

introduced andwithdrawn into thecylinder through said piston element. a 7

6. A packaging machine as defined in claim 5, in which the upper end of the piston element is open and the cylinder element is mounted for. upaand-down movement above said open upper end, and in which said yieldable means is a spring pulling downwardly upon said cylinder element.

7. A packaging machine as defined in claim 1, in which said means for limiting'the movement of the movable eleable by the movable element, and a valve actuated bysaid lever for allowing fluid to escape from'said cylinder.

8. A packaging machineas defined in' claim 1, includingalso ;a means for feeding excess pressure fluid to said cylinder just before thernovable element reaches the end of its movement in jaw-raising direction.

9; A-packa'ging machine as defined in claim 1, in which I 7 ing rod being articulated atits opposite ends by universal joints, and meansfor adjustably supporting the pumping cylinder for swinging movement about an axis tangent to the path of travel of said outer'end of said crank.

V a References Cited by the Examiner M UNITED STATES PATENTS 4/41 Smith r -,53 1s2 2,765,605 10/56 Brelsford et a1; V s3 1s0 I 2 ,917,879 12/59 Aubin 53-180X FRANK E. BAlLEY, Pr in'zary Examiner;

TRAVIS s. McGEHEE, Examiner.

Claims (1)

1. IN A PACKAGING MACHINE, MEANS FOR GUIDING A TUBE OF HEAT-SEALABLE PACKAGING MATERIAL ALONG A VERTICAL DOWNWARD DIRECTION, MEANS FOR FILLING THE TUBE FROM ABOVE WITH A PRODUCT TO BE PACKAGED, A PAIR OF TRANSVERSE SEALING JAWS MOVABLE TOWARD AND AWAY FROM EACH OTHER TO PRODUCE TRANSVERSE HEAT SEALS IN THE TUBE, SAID JAWS BEING ALSO MOVABLE BACK AND FORTH IN A VERTICAL DIRECTION TO ADVANCE THE TUBE DOWNWARDLY WHILE THEY ARE TOGETHER AND TO RISE WHILE THEY ARE SEPARATED, AND A HYDRAULIC PISTONCYLINDER SYSTEM FOR CONTROLLING THE UP-AND-DOWN MOVEMENTS OF SAID JAWS, SAID SYSTEM COMPRISING: A PISTON ELEMENT AND A CYLINDER ELEMENT ONE OF WHICH IS POSITIONALLY FIXED AND THE OTHER MOVABLE UP AND DOWN, MEANS CONNECTING SAID JAWS TO THE MOVABLE ELEMENT FOR ACTUATION THEREBY, YIELDABLE MEANS CONSTANTLY URGING SAID MOVABLE ELEMENT IN JAW-ADVANCING DIRECTION, MEANS FOR LIMITING THE MOVEMENT OF THE MOVABLE ELEMENT IN JAW-RAISING DIRECTION, AND AN ADJUSTABLE PUMPING MEANS FOR INTRODUCING AND WITHDRAWING PRESSURE FLUID INTO SAID CYLINDER, SAID PUMPING MEANS BEING ADJUSTABLE WITHOUT INTERRUPTION OF MACHINE OPERATION FOR VARYING THE AMOUNT OF FLUID WITHDRAWN FROM SAID CYLINDER TO CONTROL THE EXTENT OF JAW-ADVANCING MOVEMENT OF SAID MOVABLE ELEMENT.

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