US3073089A - Packaging machines - Google Patents

Packaging machines Download PDF

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Publication number
US3073089A
US3073089A US89427A US8942761A US3073089A US 3073089 A US3073089 A US 3073089A US 89427 A US89427 A US 89427A US 8942761 A US8942761 A US 8942761A US 3073089 A US3073089 A US 3073089A
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Prior art keywords
feed trough
articles
sealing rollers
webs
rollers
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US89427A
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Davis Frederick Lewis
Davis Edward John Albert
Berry Francis Douglas
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London Rubber Co Ltd
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London Rubber Co Ltd
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B65CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65BMACHINES, APPARATUS OR DEVICES FOR, OR METHODS OF, PACKAGING ARTICLES OR MATERIALS; UNPACKING
    • B65B9/00Enclosing successive articles, or quantities of material, e.g. liquids or semiliquids, in flat, folded, or tubular webs of flexible sheet material; Subdividing filled flexible tubes to form packages
    • B65B9/02Enclosing successive articles, or quantities of material between opposed webs

Definitions

  • This invention relates to packaging machines and, more particularly, to machines for the packaging of flexible thin-walled rubber articles, such as prophylactics, whether formed with a plain or teat end, within a cavity formed between two webs of material formed of thermoplastic material or faced with such material, the webs being heat sealed after introduction of the articles therebetween.
  • flexible thin-walled rubber articles such as prophylactics, whether formed with a plain or teat end
  • the webs being heat sealed after introduction of the articles therebetween.
  • the surplus material of the teat itself has commonly been required to be trapped within the last turn or turns of the roll of the wall of the film, in order that it should not offer an obstruction to the form of packaging employed due to its tendency to trail or otherwise be displaced and thereby prevented from being enclosed between the webs of packaging material.
  • This operation is normally effected by hand rolling which thus reduces the rate at which the articles can be handled or, where this expedient has not been employed, has necessitated the use of webs of packaging material of suflicient width as to be clear of the teat in whatever direction it may lie.
  • a packaging machine for enclosing articlesv in individual packs comprises a conveyor carrying a plurality of supports for articles to be packaged, means for moving said conveyor step-bystep to present each support in turn at a transfer station, means for transferring an article from a support at the transfer station to a feed trough aligned with complementary cavities in a pair of co-opcrating heated sealing rollers, and pusher means for progressively advancing the article along the feed trough into engagement with and for enclosure by, opposed webs of packaging material consisting wholly or in part of a thermoplastic composition as the said webs are fed into the pass between the sealing rollers, so that said article is drawn from said feed trough and enclosed between said webs and the latter are sealed around them to form a heat sealed package.
  • the conveyor travels in a direction parallel to the length of the feed trough and the transferring means comprise a claw movable transversely of the said direction to transfer articles from the supports into the feed trough through a lateral opening in the side thereof.
  • the claw may be arranged to compress each article against a side wall of the feed trough during the transfer operation.
  • the conveyor, the transferring means and fice the pusher means are operated by cams mounted on a common rotary camshaft and co-operating with followers mounted on pivoted levers.
  • a cutter or perforating device may be provided for severing or forming a tearing line in the webs between the packages after the latter have been formed.
  • the cutter or perforating device is preferably controlled by a further cam on the common camshaft.
  • Means may be provided for discharging a measured quantity of a liuid on to the article as it passes from the feed trough into engagement with the webs.
  • FGURE 1 is a front elevation of one form of packaging machine according to the invention.
  • FIGURE 2 is a rear elevation of the machine shown in FIGURE l;
  • FlGURE 3 is a partial plan View, on a larger scale than FIGURE 1;
  • FGURE 4 is a diagrammatic end elevation of the transferring means and part of its operating mechanism
  • FIGURE 5 is a view similar to FIGURE 4 but showing the parts in another position;
  • FIGURE 6 is a diagrammatic view of the operating mechanism for the transferring means
  • FIGURE 7 is a diagrammatic view of the operating mechanism forV the conveyor
  • FIGURE 8 is a diagrammatic view of the operating mechanism for the pusher means
  • FIGURE 9 is a diagrammatic view of the operating mechanism for the cuter device for separating the completed packages.
  • FlGURE 10 is a diagrammatic view of the operating mechanism for the uid discharging means.
  • the packaging machine comprises a box-like frame 10 mounted on a stand 11. Projecting forwardly from the front wall of the frame 10 are two horizontally spaced spindles 12 and 13 on which are mounted sprocket wheels 14 and 15 carrying a flight chain 16 the upper run of which moves from right to left in FIGURE l.
  • the flight chain carries a series of trays 17 each adapted to receive one of the articles to be packed, which, for the purposes of this description, will be assumed to be flexible thin- Walled rubber articles, such as prophylactics formed with teats, as described in the opening paragraph of the specification.
  • a feed trough 18 the left-hand end of which extends between a pair of heated rollers 19, 2t mounted to rotate about horizontal axes, to within a short distance of the plane containing the axes of both rollers.
  • the lower roller 20 rotates about a fixed axis
  • the upper roller 19 is mounted on an arm 21, pivotally mounted on a bracket 22, and is urged downwardly into engagement with the roller 20 by a spring 23, (FIGURE 2).
  • the rollers are heated internally by electrical means, the current being suplied to them through a suitable system of slip rings (not shown).
  • Each roller is formed in its peripheral surface with a series of circumferentially elongated cavities 24, the cavities in the lower roller 20 being shown in FIGURE 3.
  • Webs 25, 26 of packaging material are carried by reels 27, 2d mounted respectively above and below the rollers 19, Z and are led off the said reels on to the rollers 19. 2) so that they are carried through the pass between the rollers from right to left.
  • the feed trough 18 which, as shown in FIGURE 4, has undercut sides 29 to prevent the articles from moving upwardly out of the trough, has a lateral inlet portion 31 on to which the articles are transferred from the trays 17, the transfer being effected by a claw 32 (FGURE 4) operated to move to-and-fro across the trays.
  • FGURE 4 a claw 32 operated to move to-and-fro across the trays.
  • a pusher 33 movable to-and-fro in the feed trough 18, pushes the articles along the said feed trough into the pass between the rollers 19, 20 so that each article is inserted between the webs of packaging material as they pass round the rollers, Ibeing received in mating cavities 24 in the said rollers, and the said webs are pressed together around each article to enclose and seal it, the said webs consisting of, or being coated on their adjacent surfaces with, a thermoplastic composition such that, under the influence of the heat of the rollers, they adhere one to the other.
  • a pair of draw-orf rollers 34, 3S rotating at a somewhat higher peripheral speed than the heated rollers 19, ⁇ 2t) are provided to draw the sealed packages away from the heated rollers, and a guillotine 36 is provided to cut off the individual packages after they have been formed.
  • the packaging machine is driven by an electric motor 37, FIG-URE 2, driving, through a speed-reduction gearbox 38, a double take-olf sprocket 39.
  • a speed-reduction gearbox 38 Driving, through a speed-reduction gearbox 38, a double take-olf sprocket 39.
  • y also passes around a driven sprocket 41 on a common shaft with a pinion (not shown) meshing with a gear ring 42 on the lower heated roller 2d, and thisgcar ring 42 meshes with a corresponding gear ring 43 on the upper heated roller 19.
  • the upperdravkoff roller 34 is mounted on a weighted arm 34a pivoting about the axis of the upper heated roller 19, and is driven by a sprocket chain db from the said roller 19.
  • a jockey sprocket 44 maintains tension in the chain 4t?.
  • the other sprocket chain 4S engaging the take-off sprocket 39 passes around a driven sprocket 46 on a camshaft t7 mounted in the box-like frame 16 and having mounted on it a plurality of cams each engaged by a follower roller on one of a plurality of levers through which motion is transmitted to the flight chain 16, the transfer claw 32, the pusher 33 andthe movable blade of the guillotine 36, the several cams and their connections to the driven elements being illustrated in separate gures orr the drawings.
  • the cam for eecting movement of the flight chain 16 is shown at 4S, the said cam ,acting on a followerrr'oller 49 mounted on a lever 51 pivoted in the frame at 52.
  • a sprocket wheel 53 connected by a chain ⁇ 54 to a sprocket (not shown) xed on the spindle'of the flight chain sprocket 15 has freely rotatable on its spindle an arm 55 'carrying a pawl, (not shown) co-operating with a ratchet wheel (not shown) fixed to the sprocket wheel 53.
  • a telescopic link 56 is pivotally connected at its ends to the lever 51 and to the arm 55, and a pre-tensioned spring 7, also connected between the ysaid lever 51 and arm 55 normally holds the said link 56 telescoped to its minimum length.
  • the lever '51 is rocked 'irst'anti-clockwise as shown in FIGURE 6 and then allowed to return in a clockwise direction, the anti-clockwise movement being transmitted through the spring 57 to rock the arm 55 and effect an operative stroke of the pawl to rotate the sprocket wheel 53 and move the night chain 16 through a Vpredeterrninetl distance.
  • the transfer claw 32 is mounted on an arm Sii (FIG URES 4, 5 and '6) xed to an arm 59 pivotally connected at 61 to another arm 62 pivoted at 63 in the frame 10, the arm 62 swinging in a piane transverse to the length of the feed trough 1S so that lthe claw is movable to-andfro acrossthe Hight chain and along the inlet portion 31 ⁇ of thefeed trough.
  • the arm 62 is urged forwardly from the position shownin AFIGURE 4 by a tension spring da, and therarm 59 is urged clockwise about its pivot 61-by 'a tension spring 65, to urge the transfer claw 32 downwardly.
  • Thearm 62 Yis moved rearwardly Yagainst the ension of the spring @by a sheathed cable transmission Y the sheath 66 of which engages an abutment 67 on a limb 68 projecting laterally from the arm 62, the cable 69 being anchored to a pivoted arm 7b held against the pull on the cable by a tension spring 71.
  • the arm 59 carries a counterweighted pawl 72 co-operating with a iixed cam 73 to lift the transfer claw 32 during its forward stroke and allow it to drop to its operative position during its rearward stroke,
  • the transfer claw 32 is operated, through the sheathed cable transmission by a cam '74 (FIGURE 6) on the camshaft 47, the cam 74 being engaged by a follower roller "/5 on a pivoted lever 76 to the free end of which the cable 69 is anchored.
  • the follower roller 75 is engaging the cam 74 at the highest point of the said cam.
  • the arm 7d acts, in effect, as a xed ancho-rage for the cable 59, the spring 71 being strong enough to resist the load-s imposed on the cable by the operation of the transd fer claw, so that the sheath o6 holds the arm 62 against the pull of the sprinfy 64, in the position shown.
  • the spring 65 holds the arms S3, 59 and the claw 32 in the position sho-wn, the nose of the pawl lying against a rear portion '73a of the cam which is joined to the main edge portion 73]; of the cam by a rounded step 73C.
  • the cam 74 commences to rotate, the end of the cable which is lined to the lever 76 moves towards the sheath abutment 77, allowing the arm 52 to move anti-clockwise under the influence of the spring 64 and moving the transfer claw 32 outwardly.
  • the pawl 72 engages the step 73C of the cam 73 and tends to be rotated lanti-clockwise relative to the arm 59, such rotation being limited by cngagement of a stop surface 72a thereon with the side of the arm 59, so that the arm 59, with the pawl, is rocked anti-clockwise to lift the transfer claw 32, the arm 59 being held in this position until the pawl rides off the cam.
  • the parts are shown in chain dotted lines in FIG URE 4 in an intermediate position during the forward stroke.
  • the pawl 72 rides off the cam 73 when the arm 62 reaches the forward limit of its stroke, and the claw 32 then drops on to an abutment 17a alongside the trays 17 on the flight chain.
  • the follower roller 75 has by this time reached the lowest point of the cam 74, and con-v tinued rotation of that cam causes the arm 62 to be pulled in a clockwise direction, the pawl 72 re-engaging the cant but being rocked to the position shown in FIGURE 5, so that the claw remains in the lowered position during the backward stroke, and is lifted again only when the forward stroke commences.
  • the pusher 33 is operated by a third cam '78 on the camshaft 47, the cam 78 being engaged by a follower roller 79 on a lever 81 which is con nected by a sheathed cable transmission 82 to another lever 83 (FIGURES 2 and 8) having a forked end 84 engaging a roller 85V on a slide block 86 guided in a horizontal slot 87 in the front wall of the frame 10.
  • the slide block 86 carries, in front of the wall of the frame, a tubud lar guide 88 for a rod 89 on which the lpusher 33 is mounted, the rod 89 carrying, at its end remote from the pusher 33, a block 91, and a tension spring 92 being connected between the tubular guide 88 and the block 91 so Vas to urge the rod 89 and pusher 33 to follow the movements of the guide 88.
  • a tension spring 92 acts on the arm 83 to effect its return stroke.
  • a micro-switch 93 arranged in' the supply circuit of the electric motor 37 is mounted on the guide 8S so as to move therewith.
  • the switch 93 is normally held in the closed position byengagcment of the block 91 with its operating member 94, but, if the guide 38 moves independently of the ,pusher due to the" latter being obstructed, the operating member 94 moves away from the block S9 the switch 93 opens to stop the machine.
  • the guillotine 36 as shown in FIGURE 9, consists of a blade 96 mounted on a pivoted arm 97 and urged downwardly by a weight 98 towards a fixed blade 99.
  • the arm ⁇ 97 is coupled by a sheathed cable transmission 101 to a lever 102 pivoted to the frame 10 at 103 and carrying a follower roller 104 co-operating with a cam 105 on the camshaft 47.
  • the cam 105 is so shaped that, at a predetermined point in its rotation, the blade 96 is allowed to drop to effect a cutting action and is then lifted back to its normal position.
  • a single cylinder reciprocating pump 106 (FIGURES l and l0) is mounted on the frame 10, the piston thereof being operated by a lever 107 actuated by a cam 108 on the camshaft 47 to draw fluid, such as a lubricant, through a conduit 109 from a suitable reservoir and deliver it through a conduit 111 to a nozzle 112 just underneath the end of the feed trough 18 which projects between the rollers 19, 20. Fluid ejected from the nozzle 112 is thus fed into each package as it is being formed.
  • a hook arm 113 pivoted to the frarne 10 is movable into a position to engage the arm 107 and hold it away from the cam 108 when fluid is not required.
  • the cams are so arranged on the camshaft 47 that the various operations are effected in a predetermined sequence during each revolution of the camshaft, and the operations are so timed in relation to the rotation of the rollers 19, 20 that each article is fed into a pair of recesses in the said rollers, between the webs of packing material.
  • the articles to be packaged are laid one on each of the trays 17, the trays being moved step-by-step so that each one in turn comes into the position opposite the lateral inlet 31 of the feed trough 18, as shown in FIGURE 3.
  • the articles 114 (FGURES 4 and 5) are rolled so that they are in the form of rings each with the teat projecting to one side of the ring, and they are laid on the trays with the teat underneath and within the ring.
  • each tray is opposite the lateral inlet 31 of the feed trough
  • the transfer claw 32 moves forward and back, engaging the article and drawing it into the feed trough 18, the final inward movement of the feed claw compressing the article against the opposite wall of the feed trough so that it assumes an elongated form with its greatest dimension parallel to the length of the feed trough as shown in FIGURE 4.
  • the pusher 33 then moves along the feed trough to push the article towards the rollers 19, 20, the walls of the feed trough retaining it in the elongated condition.
  • the stroke of the pusher 33 is such that it pushes the article into the pass between the rollers 19, 20, between the webs of packing material, so that the said article is drawn inwardly by the rotation of the rollers, and the packing material is sealed around it to make a closed package.
  • uid is pumped through the nozzle 112 into the package being formed around it.
  • the completed packages are drawn away from the rollers 19, 20 by the drawn-off rollers 34, 3S, and then pass through the guillotine 36 which cuts through the webs between adjacent packages to separate them one from another.
  • the guillotine blade 96 may be replaced by a perforating blade which merely perforates the webs between the packages to facilitate their subsequent separation by tearing.
  • a blade having a deeply notched edge may be provided, and the operating means may be adjustable to vary its travel, so that it may make a short stroke as a result of which only the parts between the notches penetrate the webs to effect perforation, or a longer stroke to effect a complete severance.
  • the machine according to the invention may be arranged to pack the products without compressing them to an elongated shape, by altering the 6 stroke of the transfer claw and the width of the feed trough, and that it may also be arranged to pack tiexible articles of other shapes, or rigid articles.
  • a packaging machine for enclosing flexible articles of ring-like form in individual packs c:mprising a pair of co-operating sealing rollers having complementary cavities of circumferentially elongated form in their peripheral surfaces, means for rotating said sealing rollers, means for heating said sealing rollers, a feed trough to guide articles into the pass between said sealing rollers, and having a width less than the diameter of the articles.
  • a conveyor extending alongside the feed trough, a plurality of supports on said conveyor for articles to be pack aged, a transfer station, means for moving the conveyor' step-by-step to bring each support to a transfer station, a lateral opening in the side of the feed trough at the transfer station, transfer means to engage an article on a support at the transfer station, transfer it laterally into the feed trough and compress it against a wall of said feed trough to deform it to elongated shape, a pusher member to push each article transferred to the feed trough along said feed trough into the pass between said sealing rollers, and means for feeding opposed webs of packaging material consisting at least in part of a thermoplastic composition into thepass between the sealing rollers so that each article in turn is fed from the feed trough, between said webs and into a pair of cavities in said sealing rollers, the webs being sealed around it to form a heat sealed package.
  • a packaging machine for enclosing flexible articles of ring-like form in individual packs comprising a pair of co-operating sealing rollers having complementary cavities of circumferentially elongated form in their peripheral surfaces, means for rotating said sealing rollers, means for heating said sealing rollers, a feed trough to guide articles into the pass between said sealing rollers, and having a width less than the diameter of the articles, a conveyor extending alongside the feed trough, a plurality of supports on said conveyor for articles to be pack aged, a transfer station, means for moving the conveyor step-by-step to bring each support to a transfer station, a lateral opening in the side of the feed trough at the transfer station, transfer means comprising a claw rockabe about a pivot to raise it for passing over an article on the support at the transfer station during its outward movement and said claw being movable laterally to transfer the article from the support at the transfer station into the lateral opening in the side of the feed trough and to compress it against a wall of said feed trough to de
  • a packaging machine for enclosing flexible articles of ring-like form in individual packs comprising a pair of co-operating sealing rollers having complementary cavities of circumferentially elongated form in their peripheral surfaces, means for rotating said sealing rollers, means for heating said sealing rollers, a feedtrough to guide articles into the pass between said sealing rollers, and having a width less than the diameter of the articles, a conveyor extending alongside the feed trough, a plurality of supports on said conveyor for articles to be packaged, a transfer station, means for moving the conveyor step-by-step t0 bring each support to a transfer station, a lateral opening in the side of the feed trough at the transfer station, transfer means to engage an article on a support at the transfer station, transfer it laterally into the feed trough and compress it against a wall of said feed trough to deform it to elongatedshape, a pusher member to push each article transferred to the feed trough along said feed trough into the pass between said sealing rollers, pump means
  • a packaging machine for enclosing flexible articles of ring-like form in individual packs comprising a pair of co-operating sealing rollershaving complementary cavities of cfrcumferentially elongated form in their peripheral surfaces, means for rotating said sealing rollers, means for heating said sealing rollers, a feed trough to guide articles into the pass between said sealing rollers, and having a width less than the diameter of the articles,
  • a conveyor extending alongside the feed trough, a plu# rality of supports on said conveyor for articles to be packaged, a transfer station, means for moving the conveyor step-by-step to bring each support to a transfer station,
  • transfer means to engage an article 0n a support at the transfer station, transfer it laterally into the feed trough and compress it against a wall ofrsaid feed trough to deform it to elongated shape, a pusher into engagement with the sealing rollers, means for feeding o-pposed Webs of packaging material consisting at least in part of a thermoplastic composition into the pass between the sealing rollers so that each article in turn is fed from the feed trough, between said webs and into a pairY of cavities in said sealing rollers, the webs being sealed around it to form a heat sealed package, and a cutter device for severing a tearing line in the webs between the packages.

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  • Containers And Plastic Fillers For Packaging (AREA)

Description

Jan. 15, 1963 F. l.. DAvxs ETAL 3,073,089
PACKAGING MACHINES A Filled Feb. l5, 1961 5 Sheets-Sheet 1 Frederic/fiend; Dm/.f5 Edrmm/Mw//be Dat/f S fqna'ls @auf )as Berrj Mm MLV maf/V y W Jan. 15, 1963 F. L. DAvls ETAL 3,073,089
PACKAGING MACHINES Filed Feb. l5, 1961 5 Sheets-Sheet 2 171 remar:
Jan. 15, 1963 F. DAvls ETAL 3,073,089
PACKAGING MACHINES Filed Feb. 15, 1961 5 Sheets-Sheet 3 5J j? CANI- Jall- 15, 1963 4 F. DAvls ETAL 3,073,089
PACKAGING MACHINES Filed Feb. l5, 1961 5 Sheets-Sheet 4 ,177 vefors Jan. 15, 1963 F. DAvxs ETAL 3,073,089
PACKAGING MACHINES Filed Feb. 15, 1961 5 Sheets-Sheet 5 United States arent 3,073,089 PACKAGING MACHINES Frederick Lewis Davis, Broxbourne, Edward John Albert Davis, Chigweli, and Francis Douglas Berry, Hariow, England assignors to London Rubber Company Limited, London, England Filed Feb. 1S, 1961, Ser. No. 89,427 Ciairns priority, application Great Britain Feb. 18, 1960 8 Claims. (Cl. 53-180) This invention relates to packaging machines and, more particularly, to machines for the packaging of flexible thin-walled rubber articles, such as prophylactics, whether formed with a plain or teat end, within a cavity formed between two webs of material formed of thermoplastic material or faced with such material, the webs being heat sealed after introduction of the articles therebetween. In the packaging of such articles it is common practice to roll the article from the open end so that at the time of packaging, there is formed a rim composed of several turns of film, the surplus material of the closed end forming a loose diaphragm across the circular rim. Where the articles are formed with a teat at the closed end, the surplus material of the teat itself has commonly been required to be trapped within the last turn or turns of the roll of the wall of the film, in order that it should not offer an obstruction to the form of packaging employed due to its tendency to trail or otherwise be displaced and thereby prevented from being enclosed between the webs of packaging material. This operation is normally effected by hand rolling which thus reduces the rate at which the articles can be handled or, where this expedient has not been employed, has necessitated the use of webs of packaging material of suflicient width as to be clear of the teat in whatever direction it may lie.
It is an object of the present invention to provide a packaging machine which, whilst it is suitable for use in the packaging of many small articles, whether rigid or flexible, is particularly suitable for packing exiole thin walled rubber articles having a teat, since it enables such articles to be safely and properly enclosed in the packages without special preparation. It is a further ob- `ject of the invention to provide means whereby the articles can, if required, be packaged with a measured quantity of a suitable fluid.
According to the present invention, a packaging machine for enclosing articlesv in individual packs comprises a conveyor carrying a plurality of supports for articles to be packaged, means for moving said conveyor step-bystep to present each support in turn at a transfer station, means for transferring an article from a support at the transfer station to a feed trough aligned with complementary cavities in a pair of co-opcrating heated sealing rollers, and pusher means for progressively advancing the article along the feed trough into engagement with and for enclosure by, opposed webs of packaging material consisting wholly or in part of a thermoplastic composition as the said webs are fed into the pass between the sealing rollers, so that said article is drawn from said feed trough and enclosed between said webs and the latter are sealed around them to form a heat sealed package.
Preferably, the conveyor travels in a direction parallel to the length of the feed trough and the transferring means comprise a claw movable transversely of the said direction to transfer articles from the supports into the feed trough through a lateral opening in the side thereof.
The claw may be arranged to compress each article against a side wall of the feed trough during the transfer operation.
Preferably, the conveyor, the transferring means and fice the pusher means are operated by cams mounted on a common rotary camshaft and co-operating with followers mounted on pivoted levers.
A cutter or perforating device may be provided for severing or forming a tearing line in the webs between the packages after the latter have been formed.
The cutter or perforating device is preferably controlled by a further cam on the common camshaft.
Means may be provided for discharging a measured quantity of a liuid on to the article as it passes from the feed trough into engagement with the webs.
The invention is hereinafter described with reference to the accompanying drawings, in which:
FGURE 1 is a front elevation of one form of packaging machine according to the invention;
FIGURE 2 is a rear elevation of the machine shown in FIGURE l;
FlGURE 3 is a partial plan View, on a larger scale than FIGURE 1;
FGURE 4 is a diagrammatic end elevation of the transferring means and part of its operating mechanism;
FIGURE 5 is a view similar to FIGURE 4 but showing the parts in another position;
FIGURE 6 is a diagrammatic view of the operating mechanism for the transferring means;
FIGURE 7 is a diagrammatic view of the operating mechanism forV the conveyor;
FIGURE 8 is a diagrammatic view of the operating mechanism for the pusher means;
FIGURE 9 is a diagrammatic view of the operating mechanism for the cuter device for separating the completed packages; and
FlGURE 10 is a diagrammatic view of the operating mechanism for the uid discharging means.
Referring to FIGURES 1, 2 and 3 of the drawings, the packaging machine comprises a box-like frame 10 mounted on a stand 11. Projecting forwardly from the front wall of the frame 10 are two horizontally spaced spindles 12 and 13 on which are mounted sprocket wheels 14 and 15 carrying a flight chain 16 the upper run of which moves from right to left in FIGURE l. The flight chain carries a series of trays 17 each adapted to receive one of the articles to be packed, which, for the purposes of this description, will be assumed to be flexible thin- Walled rubber articles, such as prophylactics formed with teats, as described in the opening paragraph of the specification.
Alongside the upper run of the flight chain 16 at its left-hand end there is mounted a feed trough 18 the left-hand end of which extends between a pair of heated rollers 19, 2t) mounted to rotate about horizontal axes, to within a short distance of the plane containing the axes of both rollers. The lower roller 20 rotates about a fixed axis, whereas the upper roller 19 is mounted on an arm 21, pivotally mounted on a bracket 22, and is urged downwardly into engagement with the roller 20 by a spring 23, (FIGURE 2). The rollers are heated internally by electrical means, the current being suplied to them through a suitable system of slip rings (not shown).
Each roller is formed in its peripheral surface with a series of circumferentially elongated cavities 24, the cavities in the lower roller 20 being shown in FIGURE 3.
Webs 25, 26 of packaging material are carried by reels 27, 2d mounted respectively above and below the rollers 19, Z and are led off the said reels on to the rollers 19. 2) so that they are carried through the pass between the rollers from right to left.
The feed trough 18 which, as shown in FIGURE 4, has undercut sides 29 to prevent the articles from moving upwardly out of the trough, has a lateral inlet portion 31 on to which the articles are transferred from the trays 17, the transfer being effected by a claw 32 (FGURE 4) operated to move to-and-fro across the trays. A pusher 33, movable to-and-fro in the feed trough 18, pushes the articles along the said feed trough into the pass between the rollers 19, 20 so that each article is inserted between the webs of packaging material as they pass round the rollers, Ibeing received in mating cavities 24 in the said rollers, and the said webs are pressed together around each article to enclose and seal it, the said webs consisting of, or being coated on their adjacent surfaces with, a thermoplastic composition such that, under the influence of the heat of the rollers, they adhere one to the other. l A pair of draw-orf rollers 34, 3S rotating at a somewhat higher peripheral speed than the heated rollers 19, `2t) are provided to draw the sealed packages away from the heated rollers, and a guillotine 36 is provided to cut off the individual packages after they have been formed.
The packaging machine is driven by an electric motor 37, FIG-URE 2, driving, through a speed-reduction gearbox 38, a double take-olf sprocket 39. @ne of the two sprocket chains engaging the take-olf sprocket 39, shown at 40 in FIGURE 2, yalso passes around a driven sprocket 41 on a common shaft with a pinion (not shown) meshing with a gear ring 42 on the lower heated roller 2d, and thisgcar ring 42 meshes with a corresponding gear ring 43 on the upper heated roller 19. The upperdravkoff roller 34 is mounted on a weighted arm 34a pivoting about the axis of the upper heated roller 19, and is driven by a sprocket chain db from the said roller 19. A jockey sprocket 44 maintains tension in the chain 4t?. The other sprocket chain 4S engaging the take-off sprocket 39 passes around a driven sprocket 46 on a camshaft t7 mounted in the box-like frame 16 and having mounted on it a plurality of cams each engaged by a follower roller on one of a plurality of levers through which motion is transmitted to the flight chain 16, the transfer claw 32, the pusher 33 andthe movable blade of the guillotine 36, the several cams and their connections to the driven elements being illustrated in separate gures orr the drawings.
Referring to FIGURE 7, the cam for eecting movement of the flight chain 16 is shown at 4S, the said cam ,acting on a followerrr'oller 49 mounted on a lever 51 pivoted in the frame at 52. A sprocket wheel 53, connected by a chain `54 to a sprocket (not shown) xed on the spindle'of the flight chain sprocket 15 has freely rotatable on its spindle an arm 55 'carrying a pawl, (not shown) co-operating with a ratchet wheel (not shown) fixed to the sprocket wheel 53. A telescopic link 56 is pivotally connected at its ends to the lever 51 and to the arm 55, and a pre-tensioned spring 7, also connected between the ysaid lever 51 and arm 55 normally holds the said link 56 telescoped to its minimum length. During eachrevolution of the cam 48, the lever '51 is rocked 'irst'anti-clockwise as shown in FIGURE 6 and then allowed to return in a clockwise direction, the anti-clockwise movement being transmitted through the spring 57 to rock the arm 55 and effect an operative stroke of the pawl to rotate the sprocket wheel 53 and move the night chain 16 through a Vpredeterrninetl distance. if the ratchet mechanism or the flight chain becomes jammed, the lever 51V can move idly, merely extending the spring '57 and the link 56. N The transfer claw 32 is mounted on an arm Sii (FIG URES 4, 5 and '6) xed to an arm 59 pivotally connected at 61 to another arm 62 pivoted at 63 in the frame 10, the arm 62 swinging in a piane transverse to the length of the feed trough 1S so that lthe claw is movable to-andfro acrossthe Hight chain and along the inlet portion 31 `of thefeed trough. The arm 62 is urged forwardly from the position shownin AFIGURE 4 by a tension spring da, and therarm 59 is urged clockwise about its pivot 61-by 'a tension spring 65, to urge the transfer claw 32 downwardly. Thearm 62 Yis moved rearwardly Yagainst the ension of the spring @by a sheathed cable transmission Y the sheath 66 of which engages an abutment 67 on a limb 68 projecting laterally from the arm 62, the cable 69 being anchored to a pivoted arm 7b held against the pull on the cable by a tension spring 71. The arm 59 carries a counterweighted pawl 72 co-operating with a iixed cam 73 to lift the transfer claw 32 during its forward stroke and allow it to drop to its operative position during its rearward stroke,
The transfer claw 32 is operated, through the sheathed cable transmission by a cam '74 (FIGURE 6) on the camshaft 47, the cam 74 being engaged by a follower roller "/5 on a pivoted lever 76 to the free end of which the cable 69 is anchored. The end of the sheath 66 opposite to that engaging the abutment 67 on the arm 62 engages a fixed abutment 77 on the frame It).
in the inward position of the transfer claw 32, shown in FiGUIE 4 in full lines, the follower roller 75 is engaging the cam 74 at the highest point of the said cam. The arm 7d acts, in effect, as a xed ancho-rage for the cable 59, the spring 71 being strong enough to resist the load-s imposed on the cable by the operation of the transd fer claw, so that the sheath o6 holds the arm 62 against the pull of the sprinfy 64, in the position shown. The spring 65 holds the arms S3, 59 and the claw 32 in the position sho-wn, the nose of the pawl lying against a rear portion '73a of the cam which is joined to the main edge portion 73]; of the cam by a rounded step 73C. when the cam 74 commences to rotate, the end of the cable which is lined to the lever 76 moves towards the sheath abutment 77, allowing the arm 52 to move anti-clockwise under the influence of the spring 64 and moving the transfer claw 32 outwardly. The pawl 72 engages the step 73C of the cam 73 and tends to be rotated lanti-clockwise relative to the arm 59, such rotation being limited by cngagement of a stop surface 72a thereon with the side of the arm 59, so that the arm 59, with the pawl, is rocked anti-clockwise to lift the transfer claw 32, the arm 59 being held in this position until the pawl rides off the cam. The parts are shown in chain dotted lines in FIG URE 4 in an intermediate position during the forward stroke.
The pawl 72 rides off the cam 73 when the arm 62 reaches the forward limit of its stroke, and the claw 32 then drops on to an abutment 17a alongside the trays 17 on the flight chain. The follower roller 75 has by this time reached the lowest point of the cam 74, and con-v tinued rotation of that cam causes the arm 62 to be pulled in a clockwise direction, the pawl 72 re-engaging the cant but being rocked to the position shown in FIGURE 5, so that the claw remains in the lowered position during the backward stroke, and is lifted again only when the forward stroke commences.
The pusher 33, as shown in FIGURE 8, is operated by a third cam '78 on the camshaft 47, the cam 78 being engaged by a follower roller 79 on a lever 81 which is con nected by a sheathed cable transmission 82 to another lever 83 (FIGURES 2 and 8) having a forked end 84 engaging a roller 85V on a slide block 86 guided in a horizontal slot 87 in the front wall of the frame 10. The slide block 86 carries, in front of the wall of the frame, a tubud lar guide 88 for a rod 89 on which the lpusher 33 is mounted, the rod 89 carrying, at its end remote from the pusher 33, a block 91, and a tension spring 92 being connected between the tubular guide 88 and the block 91 so Vas to urge the rod 89 and pusher 33 to follow the movements of the guide 88. A tension spring 92 acts on the arm 83 to effect its return stroke.
Thus the pusher 33 is given a reciprocating motion to push successive articles along the feed trough 18, and it its forward movement is prevented, the guide 88 is able to= move independently. A micro-switch 93, arranged in' the supply circuit of the electric motor 37 is mounted on the guide 8S so as to move therewith. The switch 93 is normally held in the closed position byengagcment of the block 91 with its operating member 94, but, if the guide 38 moves independently of the ,pusher due to the" latter being obstructed, the operating member 94 moves away from the block S9 the switch 93 opens to stop the machine.
The guillotine 36, as shown in FIGURE 9, consists of a blade 96 mounted on a pivoted arm 97 and urged downwardly by a weight 98 towards a fixed blade 99. The arm `97 is coupled by a sheathed cable transmission 101 to a lever 102 pivoted to the frame 10 at 103 and carrying a follower roller 104 co-operating with a cam 105 on the camshaft 47. The cam 105 is so shaped that, at a predetermined point in its rotation, the blade 96 is allowed to drop to effect a cutting action and is then lifted back to its normal position.
A single cylinder reciprocating pump 106 (FIGURES l and l0) is mounted on the frame 10, the piston thereof being operated by a lever 107 actuated by a cam 108 on the camshaft 47 to draw fluid, such as a lubricant, through a conduit 109 from a suitable reservoir and deliver it through a conduit 111 to a nozzle 112 just underneath the end of the feed trough 18 which projects between the rollers 19, 20. Fluid ejected from the nozzle 112 is thus fed into each package as it is being formed. A hook arm 113 pivoted to the frarne 10 is movable into a position to engage the arm 107 and hold it away from the cam 108 when fluid is not required.
The cams are so arranged on the camshaft 47 that the various operations are effected in a predetermined sequence during each revolution of the camshaft, and the operations are so timed in relation to the rotation of the rollers 19, 20 that each article is fed into a pair of recesses in the said rollers, between the webs of packing material.
When the machine is in operation, the articles to be packaged are laid one on each of the trays 17, the trays being moved step-by-step so that each one in turn comes into the position opposite the lateral inlet 31 of the feed trough 18, as shown in FIGURE 3. The articles 114 (FGURES 4 and 5) are rolled so that they are in the form of rings each with the teat projecting to one side of the ring, and they are laid on the trays with the teat underneath and within the ring. Whilst each tray is opposite the lateral inlet 31 of the feed trough, the transfer claw 32 moves forward and back, engaging the article and drawing it into the feed trough 18, the final inward movement of the feed claw compressing the article against the opposite wall of the feed trough so that it assumes an elongated form with its greatest dimension parallel to the length of the feed trough as shown in FIGURE 4. The pusher 33 then moves along the feed trough to push the article towards the rollers 19, 20, the walls of the feed trough retaining it in the elongated condition. The stroke of the pusher 33 is such that it pushes the article into the pass between the rollers 19, 20, between the webs of packing material, so that the said article is drawn inwardly by the rotation of the rollers, and the packing material is sealed around it to make a closed package. As each article is entering the pass between the rollers, uid is pumped through the nozzle 112 into the package being formed around it.
The completed packages are drawn away from the rollers 19, 20 by the drawn-off rollers 34, 3S, and then pass through the guillotine 36 which cuts through the webs between adjacent packages to separate them one from another.
The guillotine blade 96 may be replaced by a perforating blade which merely perforates the webs between the packages to facilitate their subsequent separation by tearing.
Alternatively, a blade having a deeply notched edge may be provided, and the operating means may be adjustable to vary its travel, so that it may make a short stroke as a result of which only the parts between the notches penetrate the webs to effect perforation, or a longer stroke to effect a complete severance.
It will be evident that the machine according to the invention may be arranged to pack the products without compressing them to an elongated shape, by altering the 6 stroke of the transfer claw and the width of the feed trough, and that it may also be arranged to pack tiexible articles of other shapes, or rigid articles.
We claim:
1. A packaging machine for enclosing flexible articles of ring-like form in individual packs c:mprising a pair of co-operating sealing rollers having complementary cavities of circumferentially elongated form in their peripheral surfaces, means for rotating said sealing rollers, means for heating said sealing rollers, a feed trough to guide articles into the pass between said sealing rollers, and having a width less than the diameter of the articles. a conveyor extending alongside the feed trough, a plurality of supports on said conveyor for articles to be pack aged, a transfer station, means for moving the conveyor' step-by-step to bring each support to a transfer station, a lateral opening in the side of the feed trough at the transfer station, transfer means to engage an article on a support at the transfer station, transfer it laterally into the feed trough and compress it against a wall of said feed trough to deform it to elongated shape, a pusher member to push each article transferred to the feed trough along said feed trough into the pass between said sealing rollers, and means for feeding opposed webs of packaging material consisting at least in part of a thermoplastic composition into thepass between the sealing rollers so that each article in turn is fed from the feed trough, between said webs and into a pair of cavities in said sealing rollers, the webs being sealed around it to form a heat sealed package.
2. A packaging machine for enclosing flexible articles of ring-like form in individual packs comprising a pair of co-operating sealing rollers having complementary cavities of circumferentially elongated form in their peripheral surfaces, means for rotating said sealing rollers, means for heating said sealing rollers, a feed trough to guide articles into the pass between said sealing rollers, and having a width less than the diameter of the articles, a conveyor extending alongside the feed trough, a plurality of supports on said conveyor for articles to be pack aged, a transfer station, means for moving the conveyor step-by-step to bring each support to a transfer station, a lateral opening in the side of the feed trough at the transfer station, transfer means comprising a claw rockabe about a pivot to raise it for passing over an article on the support at the transfer station during its outward movement and said claw being movable laterally to transfer the article from the support at the transfer station into the lateral opening in the side of the feed trough and to compress it against a wall of said feed trough to deform it to elongated shape during its inward movement, a pusher member to push each article transferred to the feed trough along said feed trough into the pass between said sealing rollers, and means for feeding opposed webs of packaging material consisting at least in part of a thermoplastic composition into the pass between the sealing rollers so that each article in turn is fed from the feed trough, between said webs and into a pair of cavities in said sealing rollers, the webs being sealed around it to form a heat sealed package.
3. A packaging machine for enclosing flexible articles of ring-like form in individual packs comprising a pair of co-operating sealing rollers having complementary cavities of circumferentially elongated form in their peripheral surfaces, means for rotating said sealing rollers, means for heating said sealing rollers, a feedtrough to guide articles into the pass between said sealing rollers, and having a width less than the diameter of the articles, a conveyor extending alongside the feed trough, a plurality of supports on said conveyor for articles to be packaged, a transfer station, means for moving the conveyor step-by-step t0 bring each support to a transfer station, a lateral opening in the side of the feed trough at the transfer station, transfer means to engage an article on a support at the transfer station, transfer it laterally into the feed trough and compress it against a wall of said feed trough to deform it to elongatedshape, a pusher member to push each article transferred to the feed trough along said feed trough into the pass between said sealing rollers, pump means for discharging a measured quantity' 5 of a fluid on to the article as it passes from the feed trough into engagement with the sealing rollers, means for feeding opposed webs of packaging material consisting at least in part of a thermoplastic composition into the pass between the sealing rollers so that each article in` turn is fed from the feed trough, between said webs and into a pair of cavities in said sealing rollers, the webs being sealed around it to form a heat sealed package.
4. A packaging machine for enclosing flexible articles of ring-like form in individual packs comprising a pair of co-operating sealing rollershaving complementary cavities of cfrcumferentially elongated form in their peripheral surfaces, means for rotating said sealing rollers, means for heating said sealing rollers, a feed trough to guide articles into the pass between said sealing rollers, and having a width less than the diameter of the articles,
a conveyor extending alongside the feed trough, a plu# rality of supports on said conveyor for articles to be packaged, a transfer station, means for moving the conveyor step-by-step to bring each support to a transfer station,
a lateral opening in the side of the feed trough at the transfer station, transfer means to engage an article 0n a support at the transfer station, transfer it laterally into the feed trough and compress it against a wall ofrsaid feed trough to deform it to elongated shape, a pusher into engagement with the sealing rollers, means for feeding o-pposed Webs of packaging material consisting at least in part of a thermoplastic composition into the pass between the sealing rollers so that each article in turn is fed from the feed trough, between said webs and into a pairY of cavities in said sealing rollers, the webs being sealed around it to form a heat sealed package, and a cutter device for severing a tearing line in the webs between the packages.
5. A packaging machine in accordance withclaim 3, wherein a perforating device is provided fcr forming a tearing line in the webs between the packages jafter the latter have been formed. f
6. A packaging machine in accordance with caim 3, wherein the conveyor, the transferring means, the pusher means, the cutter device and the pump means are operated by cams mounted on a common rotary camshaft and are positively co-operating with follower rollers and mounted on pivotedfollower levers.
7. A pazkaging machine in accordance with claim 5, wherein .the conveyor is operated by a ratchet device coupled to its cam by linking means including a pretensioned spring.
8. A packaging machine in accordance with claim 6, wherein the follower levers of the transferring means, the pusher means, and the cutter device are connected to said devices operated thereby by flexible cables.
References (Jited in the le of this patent UNITED STATES PATENTS 2,083,618 ,Salsberg June 15, 1937 2280,335 Zimmick Apr. 21, 1942 2,828,590 Swartz Apr. 1, 1958 2,863,269 Pokras Dec. 9, 1958

Claims (1)

1. A PACKAGING MACHINE FOR ENCLOSING FLEXIBLE ARTICLES OF RING-LIKE FORM IN INDIVIDUAL PACKS COMPRISING A PAIR OF CO-OPERATING SEALING ROLLERS HAVING COMPLEMENTARY CAVITIES OF CIRCUMFERENTIALLY ENLONGATED FORM IN THEIR PERIPHERAL SURFACES, MEANS FOR ROTATING SAID SEALING ROLLERS, MEANS FOR HEATING SAID SEALING ROLLERS, A FEED TROUGH TO GUIDE ARTICLES INTO THE PASS BETWEEN SAID SEALING ROLLERS, AND HAVING A WIDTH LESS THAN THE DIAMETER OF THE ARTICLES, A CONVEYOR EXTENDING ALONGSIDE THE FEED TROUGH, A PLURALITY OF SUPPORTS ON SAID CONVEYOR FOR ARTICLES TO BE PACKAGED, A TRANSFER STATION, MEANS FOR MOVING THE CONVEYOR STEP-BY-STEP TO BRING EACH SUPPORT TO A TRANSFER STATION, A LATERAL OPENING IN THE SIDE OF THE FEED TROUGH AT THE TRANSFER STATION, TRANSFER MEANS TO ENGAGE AN ARTICLE ON A SUPPORT AT THE TRANSFER STATION, TRANSFER IT LATERALLY INTO THE FEED TROUGH AND COMPRESS IT AGAINST A WALL OF SAID FEED TROUGH TO DEFORM IT TO ELONGATED SHAPE, A PUSHER MEMBER TO PUSH EACH ARTICLE TRANSFERRED TO THE FEED TROUGH ALONG SAID FEED TROUGH INTO THE PASS BETWEEN SAID SEALING ROLLERS, AND MEANS FOR FEEDING OPPOSED WEBS OF PACKAGING MATERIAL CONSISTING AT LEAST IN PART OF A THERMOPLASTIC COMPOSITION INTO THE PASS BETWEEN THE SEALING ROLLERS SO THAT EACH ARTICLE IN TURN IS FED FROM THE FEED TROUGH, BETWEEN SAID WEBS AND INTO A PAIR OF CAVITIES IN SAID SEALING ROLLERS, THE WEBS BEING SEALED AROUND IT TO FORM A HEAT SEALED PACKAGE.
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US20150367970A1 (en) * 2013-01-15 2015-12-24 Advantage Pharmacy Services Llc Pill packaging

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US2083618A (en) * 1935-10-15 1937-06-15 Ivers Lee Co Packaging apparatus
US2280335A (en) * 1937-07-05 1942-04-21 Muller N V Cigarette box packing device
US2828590A (en) * 1954-05-13 1958-04-01 Ivers Lee Co Method of and machine for making packages containing solid articles and a fluent substance
US2863269A (en) * 1955-08-05 1958-12-09 Product Packaging Engineering Packaging machine

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Publication number Priority date Publication date Assignee Title
US2083618A (en) * 1935-10-15 1937-06-15 Ivers Lee Co Packaging apparatus
US2280335A (en) * 1937-07-05 1942-04-21 Muller N V Cigarette box packing device
US2828590A (en) * 1954-05-13 1958-04-01 Ivers Lee Co Method of and machine for making packages containing solid articles and a fluent substance
US2863269A (en) * 1955-08-05 1958-12-09 Product Packaging Engineering Packaging machine

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US20150367970A1 (en) * 2013-01-15 2015-12-24 Advantage Pharmacy Services Llc Pill packaging

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