US3001351A

US3001351A - Wrapping machines

Info

Publication number: US3001351A
Application number: US70244A
Authority: US
Inventors: Brook Leonard; Walker Rowland
Original assignee: Forgrove Machinery Co Ltd
Current assignee: Forgrove Machinery Co Ltd
Priority date: 1959-11-18
Filing date: 1960-11-18
Publication date: 1961-09-26
Anticipated expiration: 1978-09-26

Description

Sept. 26, 1961 l.. BROOK ETAL WRAPPING MACHINES 5 Sheets-Sheet 1 Filed NOV. 18, 1960 INveuToas Eo u n an Raak ATTORNEYS Sept. 26, 1961 L. BROoKEl-AL 3,001,351

WRAPPING MACHINES Filed Nov. 18, 1960 5 Sheets-Sheet 2 N LEON A lr) 8200K N Rau/LAND h/HLKG Sept. 26, 1961 Filed NOV. 18, 1960 L. BROOK ET AL WRAPPING MACHINES 5 Sheets-Sheet 3 Sept. 26, 1961 L. BRQoi ETAL 3,001,351

WRAPPING MACHINES Filed Nov. 18, 1960 5 Sheets-Sheet 4 fifa/0% Sept. 26, 1961 L. BROOK ETA. 3,001,351

WRAPPING MACHINES Filed Nov. 18, 1960 5 Sheets-Sheet 5 I N VENTO R5 oNnan BROUK ROWLRND /MKEl fz'g. 12.

Uhse, Calf, @Amma *HAHN ,4TH/2 wey;

United States Patent Company Limited,\.Leeds, England, a company of j Great Britain Filed Nov. 18, 1960, SerfNo. 70,244 Claims priority, application Great Britain Nov. 18, 1959 8 Claims. (Cl. 53-370) 'Ihe conventional form of twist wrapping machine includes an intermittently rotating `carrier head which presentsarticles in succession, each with a wrapper folded about it in. tubular form, to pairs of twister jaws which completethewrap by `twisting the projecting ends of the tubewrapper..

Such machines are relatively slow in operationowing to., the.. necessity for the carrier -head to dwell while articles are being fed into grippers mounted on it, while theends. of the tube of wrapper are twisted and while the v.wrapped articles vare discharged from the grippers. The object of theinvention is to provide a twist wrapping machinewhich can operate at higher speed by virtue of theV provisionl of a continuously rotating carrier head.

The invention provides a twist wrapping machine comprising a rotary-carrier head carrying a plurality of pairs of article grippers and, associated with `each pair of articles grippers, two.. pairs of twister jaws mounted on opposite` sides of -the article grippers and operable to twist` the` endsof wrappers surrounding articles held in the article glippen, means for imparting continuous rotation tothe carrier head, feed mechanism at a loading stationrfor Vfeedingincontinuous succession articles, each enclosed .in an open-ended tube of wrapping material, intothe article grippers with the tubes of wrapping materialextending tangentially to the carrier head as they enter the article grippers, means for rotating each pair ofarticle grippers in relation. to `the carrier head, after` it,leav,es` thefloading station, into position to presentthenends `ofthe `tube of wrapping material to the assc ciated twister jaws and for returning said pair of grippers to its original orientation after the twister jaws have` operated `and before it returns to the loading station toreceive another entubed article, and means for closing the article` grippers upon articles received by them attheloading stationand opening them again after the twister jaws haveoperated.

Preferably, the carrier head rotates about a horizontal axis and the feed mechanism includes a folding box forvcontinuously.forming a web of wrapping material into `a.horizontallyextending longitudinally sealed tube, means :for-.introducing thearticles into the tube at regular spacing las .the tube is formed, cutting mechanism for severing from the` tube individual open-ended tubular packages, each containing an article, and means for spacing these packages apart and feeding them into the article grippers. Preferably `also the articles are delivered in succession to the entubing mechanism from a continuously rotating pocketed feed disc.

The invention will now be described in more detail with reference to the drawings, in which:

FIG. `l is a diagrammatic `side elevation of a twist wrapping machine according to the invention,

FIG..2 is a diagrammatic plan view of the feed mechanism forfeeding entubed articles to the carrier head,

FIG. 3 is a side elevation of a modified form of feedinginechanism,

FIG. 4 is a corresponding plan View,

FIG. 5 is a sectional view showing another modified form of feed mechanism,

FIG. 6 is a detail View showing the article grippers in the positionthey occupy at the loading station,

FIG.` 7 is another detail view showing the twister jaws in operation,

FIG. 8 is a vertical section through part of the twister head,

FIG. 9 is a section on the line A-A in FIG. 8,

FIGS.n 10 and ll are views looking respectively inthe directions of the arrows B and C in FIG. 8, and

FIG. l2 isa view similar to that of FIG. 6 but illustrating mechanism for opening `and closing the article grippers.

Like reference numerals designate like parts through-Y out the figures. Y

As shown in the drawings confectionary tablets 10 to be wrapped are suppliedto the machine by a continuously rotating horizontal feed disc 11, into the pockets 12 of which the tablets are automatically fed in the Well known` manner. The tablets are lifted in succession from the pockets 12`of the .feed disc by a lifting plunger 13 which is given `a component of movement in the direction of movement of the pocket so thatthe head. of the plunger travels in anelliptical path. If necessary, in order to complete the lifting of the tablet from the pocket in the time available, a plurality of lifting plungers may be provided, one returningbelow the feed `disc while another is completing its upward stroke and` so on.

'The tablets are carried away from the feed disc along a channel 14, `defined by fixed guides, by lugs 15 `de-` pending from a continuously moving chain 16. A web 17 of heatsealable wrapping material is fed continuously from beneaththe channel 14 to a folding box 1S which forms the web 17 into a tube. As shown in FIG. 1 the tablets 10are delivered at regular spacing by the lugs 15 into the tube so formed, the lugs withdrawing up wardly to clear the tablets and the tablets being drawn through the folding 4box by the moving tube of wrapping material.

In the arrangement shown in FIGS. l and 2, the folding box 1S is so shaped that the inner faces of the edges of the web 17 are `brought together to `forrn a iin ex-` tending upwardly frorn the top of the folding box. The fin is gripped by a pair of drivenl sealing rollers 19 and drawn by them through a narrow gap between heated surfaces 20 which soften `the heat sensitive coating on the` web 17, which may for example consist of waxed paper or heat-scalable cellophane. The rollers 19 operate not only to seal the longitudinal seam in the tube formedby the contacting edges of the web but also to feed the Webforward at the desired rate from a reel. i

The tube `of wrapping material, with the tablets inside it, is fed forward between a pair ofcontinuously rotating cutting knives, one having a chisel edge 21 and the other a at anvil surface 22. Theseknives separate the tube midway between the tablets into individual tubes 23, each containing a tablet 10. The tubes 23, as the result of their passage through the knives, have attened ends.

As an alternative to the above described arrangement, the following box 18 may, as shown in FIG. 4, be arranged to form an overlap joint at the top of the tube of wrapping material which is sealed by a heater shoe 200 immediately following thefolding box. In this case the tube of wrapping material is fed forward to the cutting knives by top and bottom transport belts 24, 25. As an alternativegas shown in FIG. 5, side transport belts 26 can be used.

From the cutting knives the entubed tablets are fed individually in a continuous procession to a loading station A by top and bottom feed belts 27, 28 which feed the entubed tablets at a rate slightly faster than the rate of feed of the web 17, so forming gaps 29 between the individual tubes 23 of wrapping material and synchronising their rate of Afeed to the speed of grippers .31 on a carrier head `312. If desired, andas indicated in FIG. 2, the belts livered -in succession into pairs of article grippers 31.

mounted on a twister head 32 which rotates continuously about a horizontal axis. The tubes 23 of wrapping material are fed tangentially to the carrier headas shown in FIG. 1 and as each -pair of -grippers 31 passes through the loading station -it is closed against the opposite sides of a tube 23 and the tablet 10 within it. The grippers 3.1 remain closed, and convey the tablet in `a circular path to a discharge station B at which the grippers 31 are opened to permit of discharge of the wrapped tablet. During their passage from station AV to station B the ends of the tubes 23 of wrapping material are twisted as explained below.

It will be appreciated that each tablet is delivered to the loading station A with a longitudinally sealed tube 23 of wrapping material around it, this having been achieved by continuous motion of the elements concerned and without the use of intermittently operating elements suchas reciprocating folders. All that has to be performed on the twister head is the completion of the wrap by twisting the projecting ends of the tube 23 of wrapping material.

Y This Vis achieved by twister jaws on the carrier head. As shown in FIG. 6 a pair of twister jaws 33 is provided on each side of each pair of grippers 31. When the tablet `10 and its corresponding tube 23 of wrapping material is fed into the grippers 31 at the loading station, the tube 23 extends at right angles to the line of action of the twister jaws. Means are accordingly provided for rotating each pair of grippers 31 through 90 in relation to the carrier head as it leaves the loading station into the position, shown at C in FIG. l, in which the ends of the tube 23 are correctly presented to the twister jaws. The twister jaws, which are continuously rotated as described below, are then moved in as indicated in FIG. 7 to perform the twisting operation. They then move back to their original position prior to their return to the loading station. The twister head is shown diagrammatically only in the figures soy far discussed, but the mechanisms for imparting the required movements to the article grippers 31 and to the twister jaws 33 are shown -in detail in FIGS. 8-12, which will now be explained.

The twister head 32 includes two twister drums 3'4 mounted on opposite sides of a pocket wheel assembly 35 on a stationary horizontal shaft 36. Each twister drum 34 is rotatably mounted on a sleeve 37 keyed to the shaft 36 and having its outer end in screw-threaded engagement with an adjusting gear 39 which meshes 'with a pinion 40 on an adjusting spindle 41.Y By rotating the spindles 41, the sleeves 37 can accordingly be moved laterally to adjust the twister jaws to suit the length of the tablet tobe wrapped. Fixedto each sleeve 37 are a twister jaw opening cam 42, a twister jaw compensating cam 43 and a fixed gear 53.

Each twister drum 34 is continuously rotated by a driving gear 44 meshing with gear teeth 45 on the drum. The pocket 'wheel assembly '35 is rotatably mounted on the shaft 36 and -is rotated by one of the drums 34 through the agency of a driving pin 46. Each drum 34 carries a series of twister barrels 48, which are equally spaced in a circle opposite'the article grippers 31 on the assembly 35 and carry gears 52 meshing with the iixed gear 53 so that the barrels are continuously rotated.

j The twister jaws 33 of each pair are pivoted at 47 to one of the barrels 48' and have gearteeth 49 meshing with a rack St'mounted to slide'in the barrel 48 and urged in the direction to close the jaws 33 by a compression s pring 51. The outer end of the rack 50 is formed with -anges 54 between which engage shoes 55 attached to a forked cam lever 56, which is pivoted at 57 (FIG. 10) and carries a follower 58 engaging the cam 42. The @am 42 and the spring 51 cooperate to open and close the jaws 33 at the required points in the cycle of rotation of the twister head. It is necessary to move the barrel 48 inwards during twisting of the wrapper to compensate for the shortening of the wrapper and prevent the wrapper from tearing. The required reciprocating movement is imparted to the barrel by the cam 43, which has a track 59 engaging a follower 60 on a forked cam lever 61, pivoted at 62 (FIG. l0) and carrying shoes 63 engaging between flanges 6.4 on the barrel.

The pocket wheel assembly includes a hub ,164, connected to the driving pin 46, and a hub oap 65 which straddle a cam 66, fixed to the shaft 36 and serving, as later described, to rotate the grippers 31.. The grippers 31 of each pair are pivoted at 67 to a sleeve 68. .The j grippers 31 have gear teeth 69 engaging a rack 70 (FIG. l2) mounted to slide in the sleeve 68 and urged by a compression spring 71 in the direction to close the grippers. The sleeve 68 carries a gear 72, meshing with a gear quadrant 73, pivoted on a pin 74 and fixed to a cam lever 75 carrying a follower 76 engaging a track 77 in the cam 66. The cam 66 thus operates to rotate the grippers 31 through 90 and back again at the appropriate times" in the cycle of rotation of the twister head. Reciprocat` ing movement is imparted to the rack 70, to open the grippers 31 when required, by an arm 78 attached to a cam lever 79, which is pivoted at and carries a fol` lower 81 coacting with a cam 82 fixed to the shaft 36 alongside the assembly 35.

. What we claim as our invention and desire to secure by Letters Patent is:

l. A twist wrapping machine comprising a rot carrier head carrying a plurality of pairs of article grippers and, associated with each pair of article grippers, two pairs of twister jaws mounted on opposite sides of the article grippers and operable to twist the ends ,of wrappers surrounding articles held in the article, grippers, means for imparting continuous rotation to the carrier head, feed mechanism at a loading station for feeding in continuous succession articles, each enclosed in an openended tube of wrapping material, into the article grippers with the tubes of wrapping material extending tangentially to the carrier head as they enter the article grippers, means for rotating each pair of article grippers in relation to the carrier head, afterV it leaves the loading station, into position to present the ends of thetube of wrapping material to the associated twister jaws and for returning said pair of grippers to its original orientation after the twister jaws have operated and before it returns to the loading station to receive another entubed article, and means for closing the article grippers upon articles received by them at the loading station and opening Ithem again after the twister jaws have operated.

2. A wrapping machine according to claim 1, in which` the feed mechanism includes a folding box for continuously forming a web of wrapping material into a horizontally extending longitudinally vsealed tube, means for introducing the articles into the tube at regular spacing as the tube is formed, cutting mechanism for severing from the tube individual open-ended tubular packages, each containing an article, and means for spacing these packages apart and feeding them into the article grippers. Y

3. A wrapping machine according to claim 2, which includes a continuously rotating pocketed feed disc and means for supplying articles in succession from the pockets of the feed disc to the introducing means.

4. A wrapping machine according to claim 3, in which the introducing means is a chain conveyorcarrying down'- wardly projecting lugs.

5. A wrapping machine according to claim 2, in which said spacing means is constituted by upper-and' lower belts travelling at sufficient speed to space the packages apart.

6. A wrapping machine according to claim vl, in which the carrier head includes a pair of spaced drums each carrying a number of said pairs of twister jaws arranged equally spaced in a circle and a pocket wheel assembly disposed between and rotating withthe drums and carrying said pairs of article grippers.

7. A wrapping machine according to claim 6, in which each pair of twister jaws isfmountjed on a barrel carrying a gear which meshes withaxed gear so that the barrel is rotated continuously' in"tl1`e drum which carries it and in which each drum carries a set of cam levers coacting With a xed cam to impart opening and closing movements to the twister jaws and another set of cam levers coacting with another xedfcam to move the twister jaws towards and away from the article grippers.

8. A wrapping machine according to claim 6, in which said means for rotating the article grippers includes a set ofeam levers mounted on the pocket wheel assembly and coacting with a xed cam to rotate the article grippers through 90 from their article removing position to their twisting position and back again and said means for opening and closing the article grippers includes another set of cam levers mounted on the pocket wheel assembly and cooperating with another xedcam to impart opening and closing movements to thearticle g'n'ppers.

References Cited in the le of this patent UNITED STATES PATENTS Seragnoli May 8, '1956