US3323282A

US3323282A - Packaging machines

Info

Publication number: US3323282A
Application number: US324351A
Authority: US
Inventors: Duns John
Original assignee: Smith and Nephew Plastics Ltd
Current assignee: Smith and Nephew Extruded Films Ltd
Priority date: 1962-11-20
Filing date: 1963-11-18
Publication date: 1967-06-06
Anticipated expiration: 1984-06-06
Also published as: GB974529A

Description

June 6, J DUNS PACKAGING MACHINES Filed Nov. 18, 1963 United States Patent 6 Claims. (Cl. 53-1S2) This invention relates to packaging machines of the known kind in which a roll of centre-folded plastic film, for example polyethylene film, is mounted to turn on a horizontal axis, at the rear of the machine, to enable the outer end of the film (which is heat-sealed from a previous operation of the machine) to be pulled forwards by hand, over guides, to a loading platform at the front of the machine, where the open edges of the film are heat-sealed together and also the two thicknesses of the material at the rear of the item are heatsealed together and severed with the item to be packed between the separated plies of the film, to leave the actual end of the material extending from the roll, by the lowering of heatsealing and severing means which which has an L formation to come on the top of the film and to co-operate with longitudinal and transverse presser pads which come beneath the film, so that directly thereafter, upon the raising of the heat-sealing and severing means, the item is completely enwrapped with the plastic film, to constitute a fully-covered sealed package, whilst the outer end of the film extending from the roll is left sealed ready for the next operation.

It is an object of the invention to provide a packaging machine of this kind which can be readily adapted between individual heat sealing operations to package items of different widths neatly and etficiently.

In the preferred arrangement, the position of the longitudinal presser pad is adjustable, the heat sealing and severing means being hinged about an axis fixed relatively to such presser pad.

As a consequence, generally in accordance with this method of carrying the present invention into effect, the heat-sealing and severing means and its co-operating pad (the upper surface of which extends a desired distance above the platform) which act on the open side of the double film, are carried on adjustable means under the control of the operator so that they can be moved parallel to their usual outer extreme position, to narrow the width of the package. This movement takes place with the heat-sealing and severing means in the upper position, so that when the operator holds the two open edges of the film together, by, say, the left hand, and then lowers the sealing means, and at the same time moves it towards the other parallel closed edge of the doubled film by the right hand, this action will cause the upwardly projecting portion with the presser pad at the top, to edge the item, located between the two thicknesses of the film, to the closed edge, to fill the corners evenly, whereupon the sealing and severing means is pressed down to seal and sever the open edge, leaving a slight off-cut, and to effect the transverse heat-sealing and severing.

Where both the longitudinal and transverse presser pads are fixed, then in this case according to the present invention a packaging machine of the type to which the invention relates, has the roll of plastic film mounted so that it can be adjusted laterally within certain limits in the direction of its axis.

The fixed presser pads co-operate with the sealing and severing means of L formation, which can have its normal lowering and raising movements but which is not laterally adjustable as in the previous case.

The adjustability in the lateral direction, of the roll of 3,323,282 Patented June 6, 1967 film, however, provides for the variation of the width of the packages as it provides for the relative lateral movement between the pulled-out portion of the film, which is located on the loading platform, before the severing and scaling is effected.

Any suitable mechanical means may be provided for effecting the lateral movement of the roll of film. This movement may also be imparted to a side wall of the platform which cooperates with the closed edge of the doubled film, for this latter always to be accurately positioned and to give the operator greater freedom for ingigging the goods between the open edge of the doubled As a further feature of the present invention, in addition to the above for varying the width of the packages within a certain range, means are provided for vertically adjusting the level of the loading platform so that it can be set to take packages of varied depths, lying between the minimum and maximum of the range of depths concerned.

For this purpose the platform is separate from the frame and support of the machine, and such platform on its underside :has bearings for horizontal pivots, which can be pins or spindles, for the outer ends of parallel similar levers, suitably spaced apart from front to back and from side to side. The lower ends of these levers are mounted on horizontal pins or spindles and supported in hearings in the upper framework structure of the machine, and the axes of these pivots are directed from the front to the rear of the machine.

At the front, the lower horizontal spindle which is located adjacent the operating side of the machine, has

afiixed thereto an operating lever terminating in a hand grip or the like. This lever has an indicator working over a fixed angular scale, and means for holding the operating lever in any set position.

In one extreme position, the lever is set to hold the platform in its uppermost position, which will accommodate packages of the minimum depth; in the other extreme position the lever is set to hold the platform in the lowermost position, to take packages of the maximum depth. Any desired number of retaining positions for the lever may be arranged between the two limits of its action.

In order that the invention may be better understood, it will now be described with reference to the accompanying drawings which are somewhat diagrammatic, are given by way of example only, and in which:

FIG. 1 is a diagrammatic perspective: view of one embodiment of a machine constructed according to the invention.

FIG. 2 is a front elevation of parts of a machine such as shown in FIG. 1, with some of the parts indicated in two positions to illustrate the method of operating the machine, and

FIG. 3 is a similar view to FIG. 2 but of another method of carrying the invention into effect.

In the method of carrying the invention into effect shown in FIGS. 1 and 2, the machine comprises an upper framework 4 supported by legs 5 and having a rear boxlike portion 6 containing the usual electrical equipment (not shown) for connection to the heat'sealing and severing means. This portion 6 has attached thereto a bearing framework 7 for the roll 8 of doubled film material, which has the usual two thicknesses 9 and 10, with the closed edge 11 and two

open edges

12 and 13.

The material, as it passes from the roller 3, is held opened out by a separator plate 14 carried at the rear by frame members 15 and 16 attached to one side member of the main framework 7. The box-1ike structure terminates at its front in a wall 17 which extends downwards a desired depth and forms the rear wall against which the packages abut. Its upper edge has the pressure pad '18 for co-operation with the portion of the heat-sealing and severing means which effects the transverse cut.

19 is the loading platform, which is separate from the frame and supports of the machine. On its underside it has bearings for horizontal pivots 20 for the outer ends of parallel similar levers 21, spaced from the front towards the rear wall 1'7, as shown in FIG. 1 which also shows slots 22 in the upper framework of the machine to allow for the movements of the levers 21.

The lower ends of these levers are mounted on a shaft 23, only the front end of which appears in the drawings, which is mounted in bearings and extends from the front of the framework 4 to the portion of the wall 17 just below that seen in FIG. 1. This shaft is angularly adjusted by an operating lever 24 of the known kind in which a spring-pressed and works over an angular gate 26, to hold the lever 24 in any set position.

Two other levers are provided, similar to the levers 21. Only one of these, 27, appears in FIGS. 2 and 3. This lever 27' and the other similar lever are parallel to the levers 21 and are similarly pivoted beneath the platform 19 but laterally spaced from the front and rear levers 21. The front lever 27 is pivoted at its lower end, as indicated at 28, FIG. 2, to the front framework 4, and this lever and the front lever 21 work in a common slot 29. The rear lever corresponding to 27 is pivoted to the portion of the wall 17 which projects downwardly from the part appearing in FIG. 1.

By the whole of the above construction the loading platform can be set into a series of positions. As shown in FIGS. 1 and 2, it is in its highest position so that the packages will have the minimum thickness. When set to its lowest position by turning the handle 24 in an anticlockwise direction (iFIG. 2) through 90, the thickness of the package is a maximum and almost equal to the total height of the rear wall 17. The gate 28 allows for settings of the platform 19 for packages of intermediate thicknesses between the above limits.

30 is the side wall against which the closed edge of the doubled film is positioned. This side wall, in the construction of the machine shown in FIGS. 1 and 2, is the same height as the rear wall 17 and is fixed to the side of the framework 4 and extends from the front of said framework to the position of the rear wall 17. As will be seen from FIG. 1, this side wall 30 is of openwork construction to allow portions of the loading platform to pass therethrough when the said platform is in some of its lower positions. To allow for this, the platform 19 has slots 31 (one of which is seen in FIG. 1) to allow the portions between the slots to pass through the side wall 30.

In the construction of the machine being described, the heat-sealing and severing means comprises a pivoted rectangular frame as shown in FIG. 1, comprising a front lever arm 32 and a rear lever arm 33, pivoted in positions intermediate their ends at 34 and 35 respectively, to

brackets

36 and 37. These lever arms are interconnected at one end by a handle or operating rod 38, and at their other ends by a spindle carrying a counterbalance weight 39.

The rear lever arm 33 carries the heat-sealing and severing means 40 of usual construction (not shown in detail) for effecting the transverse heat-sealing and severing of the doubled film, to leave a closed end 41 to the portion of the doubled film extending from the roll 8. This heatsealing means co-operates with the presser pad 18 already referred to. From this heat-sealing and severing means there extends further heat-sealing and severing means 42 at right angles thereto, which is also connected to the lever arm 32. This heat-sealing means 42 effects the longitudinal heat-sealing and severing parallel to the closed side 11 of the doubled film and spaced therefrom according to the width of the package being formed, such 4 spacing being within the range of widths capable of being dealt with by the machine.

To effect this, the

brackets

36 and 37 are fixed to the ends of horizontal rods, capable of transverse sliding movement. The front rod 43 (FIG. 2) slides in a bearing 44 in the framework 4 just beyond the slot 29 and also between guides on a downwardly extending member of the frame 4 (just beyond the slot 29). Towards its other end this rod is fixed to a sleeve bracket 46 at the lower front corner of a movable openwork side wall 47 having the same height as the side wall 30 and rear wall \17. The upper edge of this side wall 47 has a presser pad 48 for co-operation with the heat-sealer and severer 42. There is also a sleeve bracket 49 for the end of an.- other horizontal sliding rod 50 at the rear lower corner of the side wall 47. This other rod 53 is fixed to the bracket 37.

Slots 51 in the platform 19 permit portions of said platform to project through the side wall 47, to allow the position of this latter to be adjusted by its limits of setting.

In operation it will be realised that the rods 43 and Si), together with the

brackets

35 and 37 and pivoted framework carried thereby, are all adjustable by the operator to bring the side wall 47 nearer to or further away from the fixed side wall 30, according to the width of the package before the heat-sealing and severing is effected.

The item which has been located in the closed end of the film in FIG. 1, is for a small package of minimum depth. Its width is also small and as a consequence the movable wall 47 has been moved to pack the item into close-fitting position before sealing.

In FIG. 1 the position shown is just prior to the sealing operation, with the item held more or less tightly between the two

walls

30 and 47 and up against the rear wall 17. The lateral excess material of the open edge thereof passes over the top of the wall 47 and pad 48, on to the platform 19. Upon depressing the pivoted frame by pulling down on the rod 38, the heat-sealing and severing members move in the direction of the arrowed paths so that at the end of the movement and subsequently applied slight pressure, the member 40 heat-seals and completely severs the material transversely, to leave the portion proceeding from the roll 8 with a beaded heatsealed and ready to receive the next item.

At the same time the member 42 presses on the material passing over the pad 48 and wall 47, to heat-seal and sever the material in this position. As a consequence of all this heat-sealing and severing action, the item enclosed in the film material is completely severed therefrom, to form the required package, which is neat in appearance and closely packed.

To compress the pack during the heat-sealing operation, the pivoted frame preferably has a resilient U-shaped frame 52 as shown supporting a sheet 53 of flexible material, for example strong canvas, connected thereto, which presses on the upper surface of the pack in a resilient manner. In some cases the canvas could be connected to the pivoted frame and supported by tension springs.

In the method of carrying the invention into effect shown in FIG. 3, the roll 54 of plastics material is mounted so that it can be adjusted within certain limits in the direction of its axis. The side wall 55 adjacent the open side of the doubled film in this case is fixed and has a presser pad 56 on its upper edge to co-operate with the pivotal heat sealer and severer 57 of L formation as before, except in this instance its pivotal axis is not laterally adjustable but remains in a fixed position. However, the side wall 58 which is against the closed edge of the double film has the same adjusting movements as the roll 54 of film.

The invention is not limited to the precise forms or details of construction herein described, as these may be varied to suit particular requirements.

What I claim is:

1. A packaging machine for wrapping articles of varying sizes in a plastics film of heat scalable material comprising in combination:

a frame,

a loading platform on said frame for supporting a package to be sealed,

means for supporting a roll of centre-folded heat sealable plastics -film at the rear of said loading platform,

a separator between said loading platform and said roll supporting means for separating the two plies of film as it is unrolled and drawn forwards towards said platform, heat sealing and severing means of L-formation, a transverse presser pad at the rear of said platform, a longitudinal presser pad extending forwardly from said transverse pad at one side of said platform,

means attaching said heat sealing and severing means to at least said longitudinal presser pad for movement of said heat sealing and severing means towards said presser pads for co-operation with said presser pads to effect a heat sealing operation, and

means associated with said frame providing for movement of at least said longitudinal presser pad together with said heat sealing and severing means attached thereto laterally of the film relative to said roll support means and said separator.

2. A packaging machine according to claim 1 in which said roll support means is axially fixed relatively to said frame and said separator is fixed to said frame and in which said means associated with said frame comprises horizontal members slidable in said frame laterally of said film, at least said longitudinal presser pad being fixed to said horizontal members, said attaching means comprising means pivoting said heat sealing and severing means to said horizontal members.

3. A packaging machine according to claim 1 in which said longitudinal and transverse presser pads are fixed to said frame, said attaching means comprising means pivoting said heat sealing and severing means to said frame about a fixed axis, and in which said means associated with said frame comprises means mounting said roll support means on said frame to permit axial movement of said roll.

4. A packaging machine according to claim 1 which furthercomprises means mounting said platform on said 4 frame for vertical adjustment of said platform relative to said presser pads.

5. A packaging machine according to claim 1 which further comprises a frame to which said heat sealing and severing means is attached and -a sheet of flexible material resiliently connected to said frame for compressing a package during a heat sealing and severing operation.

6. A packaging machine for wrapping compressible articles in a plastics film of heat scalable material comprising in combination:

a machine frame,

a loading platform on said frame for supporting a package to be sealed,

means for supporting a roll of centre-folded heat sealable plastics film at the rear of said loading platform,

a separator between said loading platform and said roll supporting means for separating the two plies of film as it is unrolled and drawn forwards towards said platform,

a framework,

heat sealing and severing means of L-forma-tion secured to said framework,

a transverse presser pad at the rear of said platform,

a longitudinal presser pad extending forwardly from said transverse pad at one side of said platform,

means mounting said framework relative to said machine frame for movement of said heat sealing and severing means towards said presser pads for cooperation with said presser pads to effect a heat sealing operation,

a sheet of flexible material, and resilient means connecting said sheet to said framework, whereby said flexible material compresses said article during a heat sealing and severing operation.

References Cited UNITED STATES PATENTS 2,919,530 1/1960 Garson et a1 53l82 2,947,127 8/1960 Herman 53-182 3,191,356 6/1965 Zelnick et al. 53-l82 FOREIGN PATENTS 914,590 1/1963 Great Britain.

TRAVIS S. MCGEHEE, Primary Examiner. FRANK E. BAILEY, Examiner.

S. ABEND, Assistant Examiner.

Claims

1. A PACKAGING MACHINE FOR WRAPPING ARTICLES OF VARYING SIZES IN A PLASTICS FILM OF HEAT SEALABLE MATERIAL COMPRISING IN COMBINATION: A FRAME, A LOADING PLATFORM ON SAID FRAME FOR SUPPORTING A PACKAGE TO BE SEALED, MEANS FOR SUPPORTING A ROLL OF CENTRE-FOLDED HEAT SEALABLE PLASTICS FILM AT THE REAR OF SAID LOADING PLATFORM, A SEPARATOR BETWEEN SAID LOADING PLATFORM AND SAID ROLL SUPPORTING MEANS FOR SEPARATING THE TWO PLIES OF FILM AS IT IS UNROLLED AND DRAWN FORWARDS TOWARDS SAID PLATFORM, HEAT SEALING AND SEVERING MEANS OF L-FORMATION, A TRANSVERSE PRESSER PAD AT THE REAR OF SAID PLATFORM, A LONGITUDINAL PRESSER PAD EXTENDING FORWARDLY FROM SAID TRANSVERSE PAD AT ONE SIDE OF SAID PLATFORM, MEANS ATTACHING SAID HEAT SEALING AND SEVERING MEANS TO AT LEAST SAID LONGITUDINAL PRESSER PAD FOR MOVEMENT OF SAID HEAT SEALING AND SEVERING MEANS TOWARDS SAID PRESSER PADS FOR CO-OPERATION WITH SAID PRESSER PADS TO EFFECT A HEAT SEALING OPERATION, AND MEANS ASSOCIATED WITH SAID FRAME PROVIDING FOR MOVEMENT OF AT LEAST SAID LONGITUDINAL PRESSER PAD TOGETHER WITH SAID HEAT SEALING AND SEVERING MEANS ATTACHED THERETO LATERALLY OF THE FILM RELATIVE TO SAID ROLL SUPPORT MEANS AND SAID SEPARATOR.