US2838897A - Wrapping machine - Google Patents

Description

`Pune 17, 195% J. s. PoNTEN ETAL WRAPPLNG MACHINE Filed March .'s. 1953 3 Sheets-Sheet 1 June 17, 1958 J. s. PONTI-:N E-rAl.

WRAPPING MACHINE sheets-sheet 2 Filed March 3, 1953 V INVENTOIQQS t/f/m/ 5. PONTE/v@ 044/- u/. PONTE/v AT TORN EYS United States arent WRAPPING MACHINE Jean S. Ponten, Oakland, and Olaf W. Ponten, Berkeley, Calif.

Application March 3, 1953, Serial No. 339,992

9 Claims. `(Cl. 53-226) The present invention relates generally to an -improve- `ment in packaging and more particularly to lan improved machine/for wrapping and sealing objects such as produce or the like.

There have been develop-ed innumerable improved containers and modes of packaging modern articles of manufacture in order that same may be readily handled and transported, however, in the handling of fresh produce the articles are commonly not individually Wrapped `as such requires a prohibitive amount of yhandling .whichis not only damaging to the articles but is also expensive and time consuming. Conventional .packaging equipment is ordinarily not adapted to handle articles such as fresh fruit or vegetables as a satisfactory .package :for :same should be inexpensive of Iitself and -of application, :the process should be quite rapid 4and non-injurious to the article packaged, and vfurther the package should "be sanitary, wholly sealed to protect the article Vand ytransparent to allow viewing of the article for sale purposes.

The present invention provides lall of the above lnoted requisities and is thus particularly well adapted ,for use in wrapping such as heads of lettuce for example, `however, the invention may be equally well employed .to :wrap any desired solid object of nominal size and is very well adapted thereto when cost, careful handling, and ,rapidity of packaging are factors in the packaging process.

Accordingly, it is an object of the present invention to provide an improved wrapping machine.

it is another object of the present invention to provide an improved machine for rapidly and fully automatically wrapping solid objects.

lt is yet yanother object of the present invention to provide an improved means for wrapping which includes means for encompassing an object with a-transparentfilm and `sealing same thereabout.

It is a further object of the present invention to lprovid-e an `improved wrapping machine :having handling means automatically removing objects from .a .conveyor belt and returning same thereto in wrapped condition.

lit is a still further object of the present invention to provide an improved wrapping machine automatically removing objects from al delivery conveyor belt, wrapping same `in a sealed transparent film and redepositing the objects on a discharge conveyor belt.

The invention possesses other objects and features of advantage, some of which, with the foregoing, will be set forth in the following description of the preferred form of the invention which is illustrated in the drawings accompanying Vand forming part of .the specification. lt is to be understood, however, that variations in the showing made by the saiddrawings and description may be adopted within the scope of the invention as set forth in the claims.

Ay preferred embodiment of the invention is illustrated in the accompanying drawings wherein:

Figure l is arplan `View of a-dualV unit constructed `in accordance with the invention with portions broken away as indicated.

Figure 2 is a sectional View taken at 22 of Figure l.

Figure 3 is a sectional view taken at .3-3 of Figure l.

Figure 4 is a partial section of the wrapping unit with the object partially wrapped and the wrapping not yet sealed.

Considering now the structural details of the illustrated embodiment of the invention and referring to the drawings there is provided two wrapping units 11 and 12 which are spaced apart and may be disposed on opposite sides of the end of a feeding conveyor belt 13. Objects to be wrapped, which in the illustrated case are heads of lettuce 14, are delivered to the wrapping machine by conveyor 'belt 13 and a handling unit 16 is disposed between wrapping units 11 and '12 for feeding the hea-ds 14 alternately to the units. A second lconveyor belt 17 may be provided for removing the wrapped heads ,14 and a trough or slide 18 extends from the wrapping units 11 and 12 to the conveyor belt 17 whereby wrapped heads which are automatically dumped onto the trough 18 by the wrapping units are directed onto the conveyor belt 17 for removal to other facilities such as storage or transportation.

The handling unit 16 functions to Vpick up heads of lettuce from the feeding conveyor belt 13 and to alternately deposit heads 14 upon wrapping units 11 and 12 and to this end includes a pair of rotatably mounted ` arms 21 and 22 adapted to swing between the conveyor belt 13 and the wrapping units 11 and 12 respectively. Handling unit 16 is actually `a double unit having two identical portions which are properly phased by means noted below to each serve one of the wrapping units, and considering the right hand portion in Figure 2 it will be seen to include in addition to horizontal .arm 21 a vertical shaft 23 extending Ythrough the end of arm 21. Shaft 23 is movably mounted in a housing 24 which may be rigidly secured to wrapping units 11 and 12 and which has an elongated vertical aperture accommodating shaft 23 vin slidable and rotatable relation. Shaft 23 has an expanded section fitting Within the aperture in housing 24 and a'shoulder 26 extends about the top of this expanded portion. Arm 21 slidably engages shaft 23 above shoulder 26 thereon and is keyed or otherwise secured `to shaft 23 to rotate therewith. At the upper end of shaft 23 there is rigidly secured a second arm 27 which extends generally parallel to and above `arm 21 and has at its outer end a stub shaft 28 depending vertically therefrom. 'Stub shaft 28 is rigidly secured to second arm 27 and extends into slidable engagement with the end of ar-m 21 through a vertical aperture therein and stub shaft .28 is threaded about the portion extending into the aperture .in arm 21. There are provided at the end of arm 21 tongs which include a plurality of curved ngers 29 all having gear teeth formed on a semicircle about their `upper ends and being pivotally mounted at their upper ends in radial slots in the end of arm 21 with the teeth thereon vin engagement with the threaded stub shaft 28. Fingers ,29 are spaced circumferentially about stub shaft 28, being three in number in the illustrated embodiment, 4and `as they are pivoted it will be seen that they will :pivot inwardly and outwardly as stub shaft 28 moves up out of and down into the aperture in arm 21 respectively, by virtue of theengagement of the stub shaft threads and the gear teeth on the ends of the lingers. The stub shaft threads and finger gear teeth are formed to mesh together ,to provide the above noted finger movement and the relative-motion of stub shaft 28 and arm 21 is provided by lthe vertical movement of shaft 23. Thus shaft 23 moves vertically as well as moving rotationally and with regard .tof'this verticalrmotion, in Figure 2 the shaft of the left Ydoes not rotate.

portion of the handling unit is shown at its lowest point of travel where the shoulder thereof is disposed within the housing aperture well below the top of housing 24. In this position the upper and lower arms are in contact and the stub shaft is fully within the lower arm to dispose the lingers at maximum extension. As shaft 23 is raised arm 21 at lirst remains at rest upon the top of housing 24 while upper arm 27 which is rigidly secured to shaft 23 is raised to withdraw stub shaft 23 from arm 21 and close ngers 29. Further upward motion of shaft 23 brings the shoulder 26 thereon into Contact with arm 21 and thus raises same to raise the tongs formed by lingers 29. A converse process occurs when shaft 23 is lowered so that the handling unit will be seen to close lingers 29 in lowered position as about an object and thence to raise lingers 29 as for transportation of the object gripped by the lingers, while the lingers upon lowering open to release the object gripped therein,

With regard to the production of the above noted vertical reciprocation of shaft 23 as well as rotational motion thereof, there is connected in rotational relation to the bottom of shaft 23 a link 31 which extends downward from the lower end of shaft 23 and which is slotted to lit about a horizontal revolving drive shaft 32 which may be mounted between wrapping units 11 and 12. A cam 33 is keyed or otherwise rigidly attached to drive shaft 32 and a cam follower 34 is rotatably mounted on link 31 above cam 33 in rolling contact therewith. As drive shaft 32 rotates, the cam 33 thereon also rotates and moves link 31 upward and downward by the rolling contact of cam follower 34 upon cam 33. Drive shaft 32 is operated from the motor 36 of wrapping unit 11, and for this purpose drive connections may be provided such as a chain drive 37 engaging drive shaft 32 and a short shaft 38 geared in turn to a sprocket wheel 39 of a second chain drive 41 having an upper sprocket wheel mounted on a rotatable shaft 42. The rotational motion of the handling unit arm 21 is controlled by a Icam 43 secured to and rotating with shaft 42. This cam 43 is engaged by a cam follower or link 44 which has a roller attachment riding on the cam and which has a forked end disposed about shaft 42. The opposite end of link 44 is pivotally connected to the rack 46 of a rack and gear arrangement 47 wherein gear teeth are formed on support shaft 23 below housing 24. Rack 46 is mounted in a slot in housing 24 to slide horizontally therein and rack 46 is moved by link 44 at a speed and of a distance dictated by cam 43 followed by link 44. Thus as shafts 32 and 42 rotate together through chain drives 37 and 42 support shaft 23 is moved vertically by the link 31 through the cam 33 on drive shaft 32 and is rotated by link 44 driven by lcam 43 on shaft 42. As rack 46 of the rack and pinion 47 moves to rotate shaft 23 engaged thereby it will be noted that support shaft link 31 would rotate with shaft 23 unless otherwise mounted thereon and thus link 31 is joined to shaft 23 as by an aperture in the top of link 31 into which the end Vof shaft 23 eX- tends, a bearing being preferably provided in this con'- nection.

While the above noted elements and connection provide the motion of support shaft 23, the degree and timing of the relative motions are controlled by the shape of cams 33 and 43 and in this respect attention is invited to the shape of cam 43, shown clearly in Figure 2. Cam 43 has somewhat of a triangular shape in plan view with one point having a constant radius curve and the side opposite this point also having a constant radius curve of much greater radius. A constant radius curve does not move the cam follower so that when the roller on link 44 passes over theseV curved portions of cam 43 no motion is imparted to rack 46 and support shaft 23 Thus shaft 23 with arm 21 in the position shown in Figure 2 will not rotate until cam 43, rotating in a clockwise direction, turns sufficiently t place the roller of link 44 in contact with the relatively unit 11, as shown.

,4 straight lower side of cam 43, at which time shaft 23 will be rotated to swing arm 21 to a position over conveyor belt 13. At this point the constant radius curve of large radius on cam 43 will be contacted by the cam follower so for another period the shaft 23 will not rotate. As the cam follower or link 44 contacts the other relatively straight portions of cam 43 the shaft 23 will be rotated to swing arm 21 back into position over the wrapping During the above-described rotational motion `of shaft 23 and arm 21 the cam 33 on drive shaft 32 has been raising and lowering shaft 23 and with cam 33 having a conliguration similar to that of cam 42 and shafts 32 and 42 properly phased by the connections therebetween arm 21 will be lowered from the position shown in Figure 2 and the lingers 29 opened to release the object held thereby upon the wrapping unit 11. The arm 21 will then be rotated back to the conveyor belt 13 as noted above and when rotationally stationary there the ngers 29 will be open and the arm 21 raised to grip and remove an object from the belt. The arm then swings back to the position shown in Figure 2 and one cycle of operation is complete. It will be appreciated that the motion of arm 21 and the action of fingers 29 is controlled by the rotation and vertical motion of shaft 23 which is in turn a function of the configuration of cams 33 and 43. Thus the degree of motion of arm 21 and the timing of the movements thereof may be determined for any particular installation and controlled by proper design of cams 33 and 43, the above described arm motion being set forth merely as an example which is particularly desirable for the illustrated arrangement.

As previously noted the handling unit 16 illustrated includes two identical arm and linger members which are adapted to move between conveyor belt 13 and opposite wrapping units. Preferably the arms 21 and 22 operate alternately so that when one is picking up an lobject from the conveyor belt the other is depositing an object at its wrapping unit and this phased `operation is obtained by disposing the cam 33 and its counterpart for arm 22 in opposite relations on drive shaft 32 and by placing the shaft 23 and its counterpart for arm 22 with the teeth thereon in opposite relation to engaging rack 46 of the rack and gear arrangement 47, all as shown in Figure 2.

Considering now the wrapping units 11 and 12, only unit 11 will be described inasmuch as unit 12 is identical thereto in composition and operation. Wrapping unit 11 includes a rigidly constructed table 51 having a plurality of support members 52 adapted to rest upon or be secured to a lloor or the like and adequate cross members to insure stability. Table 51 has a horizontal planar table top 53 which is preferably coplanar with the table top of wrapping unit 12 and there is provided in the center of table top 53 an aperture 54 which is located directly below the end of arm 21 of handling unit 16 when the arm is swung into position to release the object carried by the lingers 29 thereof. Within apertures 54 there is disposed a cup or support plate 56 which preferably has a concave upper surface to receive and retain an object placed therein by lingers 29 of handling unit 16 and which is adapted to be lowered below table top 53 while carrying such object. Wrapping of the object may be accomplished with any one of numerous suitable substances that are relatively strong and pliable and are available in sheet or roll form, it having been found that lettuce packaging may be advantageously accomplished with a thermo setting plastic such as cellophane or the like. Wrapping is accomplished by enveloping the lettu'ce 14 with a thin transparent lilm 57 and there is provided dispensing means to dispense quantities of lilm for successive wrapping operations. The dispensing means 58 may include rotatably mounted shaft 59 disposed atop table 51 at a distance from aperture 54 therein and adapted to carry a roll of lilm 57. The lilm 57 may be removed from the roll by a pair of rollers 60 which con- 53,'as shown.

-secured `through bar 63 near its center.

Y Y Vif; tact the film and bear upon each other or upon tabletop Means such as a pair of' endless tapes and rollers 61- mounted in table Atop'53 may be provided to draw the 1m"57-over the aperture' 54 1in table top 53. A single piece of film 57 is used towrap each head of lettuce and a vertically movable knife 62 may be mounted above table top 53 between the roll of film57 and table aperture 54 to cut lthe film at'the propertlength to provide an individual sheet thereof foreach wrapping operation'. The film dispensing means 58 may be either hand or power operated and if power driven the operating portions thereof may be conveniently cam connected to motor 36-so that the film dispensing will be synchronized with the handling and wrapping operations. It will be appreciated that the knife 62 is displaced from aperture 54 a predetermined distance and is operated at a ,particular point of travel of film 57 thereunder to cut off a sheet rof .the film 57 having alength somewhat greater .than the diameter of the lettuce heads, the film widthhaving a like dimension so that a substantially square sheet. offilm 57 is'employed to wrap each object.

vWith regard to theactual wrapping operation, cup or carrying 'plate'56 is secured to the top of a shaft or bar 63 that is mounted vertically in slidable relation to two or `more bearings which are in turn joined to suitable structural members of table 51. Vertical reciprocation of bar 63 is produced by a cam 64 rigidly mounted on a horizontal shaft 66 and rotated by motor 36 through a pulley ,arrangementl The rotary motion of cam 64 is transferred into translation of bar 63 by a rocker arm 68 which is pivotally mounted at one end to a member`52of table 51 or a projection thereon-v and which hasa forked end engaging a horizontal pin 69 rigidly Arm 68 is preferably formed as` two parallel elements is rigidly joined together with aspace therebetween and having each element forked atone end to engage pin 69 on both sides ofbar- 63 whilea roller or cam follower 71 is mounted between ythe arm'elements near their centers. .68 is-disposed above cam 64 with cam follower 71 rest- .ingupon cam 64 so thatarm 68 pivots aboutitsrendas its .contact with` cam64-moves verticallyin accordance with Arm of cup 56, in the illustrated embodiment, cam 64 has a peripheral configuration resembling anegg, i. e., an oval :with onefend smaller than the other, and has a concave portion on oneside adjacent the smaller end. The cam t rotates'clockwise so that the' cup 56 is moved into align- `ment withV table top 53 directly under a sheet kof wrappingttilm v57 and there-stops momentarily while a lettuce head '14' is deposited thereon by arm 21 of handling device'16. Thecup and contents then move downward Tbelow the 'table top 53 where the wrapping operation is completed inthe manner explained below. At 'the bottom `of thecup 'travel it `again hesitates \momentarily ywhilethe* cup is unloaded and then the cup returns upward into alignment with table top 53 Where the opera- 4v'tion isv repeated.

IAsnoted above, a sheet of wrapping film 57 is dis- 'posedupon table top `53 across theaperture 54 therein lwhen cup 56 is aligned with table top 53 and it is in this position that handling device 16 deposits lettuce head 14 upon cupl6 and the fingers 29 thereof release the lettuce head'd. The wrapping unit 11 is then in theposition -'shown in Figure' with cup S6 and attached bar 63 at v*their highest vertical position.

As shaft 66 is rotated clockwise fromthis positionby motor 36, cam 64 rov f .6 tates therewithso thatarm 68 resting thereon by ycam follower 71 is allowed to pivot downward. Bar `63 and attached cup `56 are thus also allowed to move downward by their own weight aslimited by the engagement of the pin 69 on bar 63 with the forked end of the pivating arm 68. Thus cup'56 moves downward carrying the lettuce head 14 and a sheet of wrapping film"57 between the cup and lettuce head. The edges of film 57 are -turned upward about lettuce head 14 by the edges of aperture 54 as cup 56 moves downward and there are provided means for engaging film 57adjacent its edges and bringing them together into sealing relation to form aY closed container about the lettuce head 14. lTheseclosyingand-sealing meansA are operated in cooperation with the lowering mechanism of cup 56 so that the closingtand sealing will be accomplished during the downward travel offcup`56 and these means may include a pair of plates 72 and '73 each-disposed directly below 'the table top53 `1on-opposite sides of aperture' 54 therein. These.. plates \72. .and A73.are.each mounted in slides or tracks 74 exvtending along opposite sides of aperture 54 and-theV plates aremadapted toslide in :these tracks towardand away fromfeach other. Preferably plate 72 includes a pair of` vertically Aspaced lparallel plates joined togethery at a distance from the leading edge thereof while plate V'73 is buta single plate member adapted to slide between the plate members of plate 72 into intimate engagement there- -Awith, the tracks being disposed to align the plates 72 and -73 fforf'this engagement.

Further, plates 72. and 73V are both preferably formed with large V notches in the adremains. These plates movetogether into engagement ascup- 56 is lowered .so that the plates gather film-"57 about lettuce head 14 until, with lettuce head below : plates 72 and 73, lm S7` extends through theV small `aperture remaining between' engaging plates 72 and 73. The film 57 may be finally secured togetherabove lettuce head 14in a-variety of ways such as stapling or ltying for example, however, a substantially airtight seal is best lforme-d with cellophane film or the like by the application of heat and pressure-to the gathered film above -lettuce Vhead 14 and to this end there'areprovidedfapair `of heaters 76 and 77 which are disposed at the square apex of the V notch in plates 72 and 73, respectively. Heater76 may be disposed between the plate elements ofplate 72 so that the heater units 76 and 77 are aligned and move directly toward each other as plates 72 and 73 are slid into` engagement. Preferably heaters 76 and 77 are electrical and may be energized through leads extending away from plates 72'and 73 to a suitable source of electric current, not shown. lHeaters 76 and 77 are adapted to engage each other with the gathered endsof film 15'7 therebetween at the maximum engagement vof plates 72 and 73 and there is thus applied to the hlm both'pressure and heat to fuse together the film 57 thereby sealing same about lettuce head 14. Overheating` of film'57 is prevented by forming plates`76 and 77V of a heat insulating material so Vthat heat is applied to'the lm only when the same is contacted by the heaters.

The motion of plates 72 Iand 73 must be synchronized with the vertical reciprocation of bar 63 and attached cup56 so that the'plates 72and 73 will move together to bring the edges of film 57 into contact for sealing the container formed thereby and to seal the container only when the lettucehead 14 on cup 56 is disposed entirely below plates 72 and 73. This is accomplished by a drive mechanism powered by the common motor-36 and including a horizontal rotatably mounted shaft`81 driven by a pulley arrangement from shaft 66 in'turn connected to motor'36. Shaft 81 rotates in bearings mounted-upontable51'and has rigidly attached tot'he same.

- where they are conveyed away to other facilities.

end thereof a connecting rod 82 of short length which is joined at its end to a pair of arms 83 and 84 extending to opposite sides of table 51 and pinned to connecting rod 82 to permit free relative rotation of the members at the connection. A pair of idle shafts 86 and 87 are mounted for rotation along the edges of table 51 below plates 72 and 73 and normal to the direction of motion of Arms 83 and 84 are connected to idle shafts S6 Vand 87 respectively by short pivotal links so that reciprocation of arms 83 and 84 rotate shafts 86 and 87 respectively. In line with the center of plates 72 and 73 there are provided two setsl of pivot links 88 and 89 each of which include a lirst link rigidly secured normal to its shaft 86 or 87 and a second link pivotally connected to the end of the lirst link and the under surface of the ladjacent plate 72 or 73. With this above described drive mechanism rotation of shaft 82 by motor 36 through shaft 66 and appropriate pulley connections causes arms 83 and 84 to reciprocate under the inuence of connecting rod 82. This reciprocation of arms 83 land 84 is applied through suitable pivotal linking, as shown, to rot-ate shafts 86 and 87 and at a distance from arms S3 and 84 the two sets of pivot links 88 and 89 are moved by the turning of shafts 86 and 87 to move plates 72 and 73 into and out of engagement with each other along tracks 74 provided therefor. Proper phasing of the verv tical reciprocation of bar 63 and the horizontal reciprocation of plates 72 and 73 is accomplished by originating both motions at a single motor 36 and adjusting the position of cam 64 as will be self explanatory from the above description.

In order to insure complete sealing of film 57, heaters 76 and 77 are preferably maintained in contact therewith for some short period of time and this may be accomplished by providing a time delay in the motion 0f plates 72 and 73 at their maximum engagement. To this end the pivotal links of arms 83 and 84 may be attached thereto by slide blocks on the arms with adjustable springs on the arms imparting the motion thereof to the pivot links as shown in Figure 3, whereby the end motion of the arms is absorbed by the springs and control is provided of the length of the time delay and the force with which the heaters are pressed together.

Automatic unloading of the wrapped head of lettuce from cup 56 may be readily accomplished by hingingcup 56 upon the upper end of bar 63 and providing a trip lug 91 attached to a structural member of table 51 and extending to a position adjacent bar 63 for contacting the under surface of cup 56. Preferably the hinge mounting of cup 56 is spring loaded so that cup 56 is normally disposed generally perpendicular to bar 63 and adjacent the bottom of travel of cup S6 it hits trip lug 91 on one side thereof and pivots to slant cup 56 and dump the contents therefrom. The trough 18 noted above is disposed adjacent bar 63 below cup 56 and extends downward toward conveyor belt 17 so that as the contents of cup 56 are dumped they slide into trough 1S and thencel downward along same to conveyor belt 17 Alternatively, there may be provided in trough 18 an aperture through `which bar 63 extends and which is also large enough for cup 56 to pass. With this arrangement cup 56 at the bottom of its travel passes through trough 18 which arrests the passage of the head of lettuce 14 that is too large to pass through the aperture in trough 18 and the lettuce head then slides or rolls down the trough to the conveyor belt 17 for transfer to some other area. It

. will be appreciated that this second alternative is only operable to unload objects larger than cup 56, however, cup 56 may be ordinarily made quite small in diameter so that the unloading arrangement is satisfactory for most objects wrapped by the device.

There has been described above a single wrapping unit 11 and the cooperating portion of the handling device 16, however, it is advantageous to employ a dual unit motors to drive the two wrapping units or a single motor.

may be employed to drive both units, however, in either case the units and handling device 16 must all be synchronized.

While a preferred embodiment of the invention has been described above both as to construction and operation it may be helpful to summarize the overall operation and thus it will be seen that as one handling arm 22 is in position to grasp a lettuce head 14 from the feeding conveyor belt 13 the other arm 21 is poised over table 51 of wrapping unit 11 preparatory to releasing the lettuce head grasped by the ngers 29 thereof. As the lettuce head 14 is deposited upon cup 56 of unit 11 with a sheet of iilm 57 upon cup 56 beneath head 14 the cup is then lowered by bar 63 while plates 72 and 73 move toward `each other to close the film 57 about the head 14. As

e film 57 about lettuce head 14. The plates 72 and 73 then move apart while cup 56 continues its downward movement until it is unloaded to slide the wrapped lettuce head onto trough 18 whence it travels downward onto conveyor belt 17. During this time arm 21 of handling device 16 has swung back to a position above feeding conveyor belt 13 and has the ngers 29 thereof extended to grasp another head of lettuce and arm 22 of handling unit 16 has grasped a head of lettuce from the conveyor belt 13 and swung about into position to deposit same upon the cup of wrapping unit 12. The procedure is then repeated for unit 12 to complete one cycle of operation and the cycles are themselves repeated to continuously and automatically wrap objects such as heads of lettuce delivered to the apparatus by conveyor belt 13.

What is claimed is:

l. An improved wrapping machine comprising a cup adapted to support an object to be Wrapped and a pliable film upon said cup beneath an object to be wrapped, a pair of plates disposed on opposite sides of said cup and mounted for reciprocation into and out of engagement with each other, drive means, connecting means joined between said drive means and said cup for lowering said cup between said plates and joined between said drive means and said plates for moving same together as said cup is lowered whereby the object will be gravitally lowered and whereby said pliable film is gathered thereby Y about the object to be wrapped, heating means upon adjacent edges of said plates for heating said gathered lm to seal same about said object to be wrapped, and means for resiliently and forcibly urging said plates towards each other and maintaining same in relatively closed position whereby the heaters may seal said lm.

2. An improved wrapping machine comprising a table having an aperture in the top thereof, a cup mounted in said aperture for vertical motion below said table top and having a bar extending downward therefrom, dispensing means upon said table top including a rotatable shaft adapted to carry a roll of pliable iilm and means for unrolling same across said aperture and cutting off lengths thereof over said aperture, a. pair of plates slidably mounted below said table top on opposite sides of said aperture and adapted to move into engagement directly below said aperture, drive means including a motor and a cam operated arm engaging said bar for lowering and raising said cup and connecting links reciprocating said piates formoving same together `as said .cup is llow- .ered therebetween to gatherv togethersaid film .above said cup, means carried by said plates for joining together the lm gathered .by said plates for .forming a closed .container, and spring means for forcibly retaining said plates in their maximum engaging position cooperating with movement of said connecting links to permit said heaters to engage said gathered film for a predetermined length of time.

3. An improved wrapping machine comprising an arm horizontally rotatable about one end thereof and having fingers depending from the free -end thereof for grasping objects, a -table having an aperture inthe top thereof -and ydisposed with said aperture on the traverse of the free-arm end, a vertically movable cup disposed in said table top aperture` for supporting an object grasped by said arm and deposited thereon by the fingers on said arm, dispensing means on said table including a roll of pliable film and means for disposing sheets thereof on said table top across said aperture whereby same is positioned between said cup and an object deposited thereon, drive means including a .cam operated rocker arm for reciprocating said cup vertically below said table top, a pair of plates slidably mounted below said table top in horizontal alignment on opposite sides of the aperture in said tabel top and connected to said drive means for horizontal reciprocation into and out of engagement below said aperture and synchronized with said cup motion to engage when said cup has moved below same for gathering said film together above the object on said cup, sealing means mounted on said plates for joining together the film gathered by said plates to wrap the object on said cup in the film, and removal means engaging said cup at the bottom of its traverse for removing the wrapped object therefrom.

4. An improved wrapping machine comprising a table having an aperture in the top thereof and adapted to have a pliable film removably disposed across said aperture, a cup disposed in said aperture and having a vertical bar depending therefrom, a pair of plates disposed below said table top on opposite sides of the aperture therein in horizontally slidable relationship, a vertical rotatable shaft spaced from the aperture in said`table top, an arm secured to the upper end of said shaft above said table top and having tongs attached to the free end thereof, said arm extending from said shaft a distance equal to the spacing of said shaft from said table top aperture, drive means, connecting means from said drive means to the bar on said cup and to said plates for vertically reciprocating said cup and horizontally reciprocating said plates in synchronism to engage said plates after said cup has moved below same whereby the film is gathered together by said plates, further connecting means between said drive means and said vertical shaft for swinging same in synchronism with the vertical reciprocation of said cup whereby the tongs on said arm are disposed above said cup when same is inthe aperture in said table top for disposing an object to be wrapped on said cup, and sealing means on said plates for joining together the film gathered together by said plates about an object on said cup.

5. An improved wrapping machine comprising a table having an aperture in the top thereof, a housing having a vertical bore therein spaced from the aperture in said table top, a shaft disposed in the vertical bore in said housing, a first arm secured to the upper end of said shaft in vertically slidable relation thereto and extending to the aperture in said table top, a second arm rigidly secured to said Vertical shaft above said first arm, a stub shaft depending from said second arm into an aperture in the end of said first arm and having a threaded lower end, a plurality of curved fingers pivotally mounted in the end of said first arm about said stub shaft and depending from said first arm with teeth formed about the upper ends thereof in engagement with the threaded portion of said stub shaft whereby relative vertical motion of said first and second arms open and close said fingers, said vertical shafthaving a shoulder thereabout below the upper end thereof and being vertically movable in said housing whereby upward motion ot' said shaft first raises said second arm above said second arm and engagement of said shaft shoulder then engages said first arm to raise same together with said second arm, .a cup having a -vertical .bar .extending downward therefrom adapted for disposition in the aperture in said tabletop to receive and ,support objects deposited thereon by the fingers of said arm, a motor, first drive means .connected to said motor and to the bar on said cup for vertically reciprocating same below said .table top, second drive means connected between .said ,motor and said vertical shaft for rotating same land vertically Ireciprocating same in synchronism with said cup for operating said first and second arms to swing same over said cup and to open the fingers thereon when said cup is moved into the aperture in said table top, a pair of horizontally slidable plates aligned on opposite sides of said table top aperture below said top and carrying sealing means, and third drive means connected to said motor and to said plates for horizontally reciprocating same into and out of engagement below the table top aperture in synchronism with said cup motion whereby said plates engage after said cup has moved downward therebetween for sealing a wrapping about an object on said cup.

6. A wrapping machine as claimed in claim 5 further defined by said first drive means including a rotatable shaft having a cam secured thereon and an arm pivotally mounted at one end and engaging the bar on said cup at the other end with the center thereof riding on said cam for vertically reciprocating said bar and attached cup, said second drive means including a rotatable shaft having a cam secured thereto upon which the lower end of said vertical shaft rides and a linear gear engaging gear teeth on said vertical shaft and connected to a cam driven from said rotatable shaft, and said third drive means including a rotatable shaft with a pivotal linkage assembly secured between same and said slidable plates for horizontally reciprocating said plates.

7. An improved wrapping machine as claimed in claim 6 further defined by a second table having an aperture therein with a second cup disposed in said aperture and a second pair of horizontally reciprocating plates below said table top, said table being disposed on the opposite side of said housing from said first table, a second vertical shaft and attached arms as said first vertical shaft and disposed in a second aperture in said housing, said second vertical shaft having teeth formed thereon engaging the linear gear of said 'second drive means in displaced relation to said first vertical shaft whereby the arms on said vertical shafts swing alternatively over their respective tables, said second drive means having a second cam identical to the cam engaging the end of said first vertical shaft |but secured to the rotatable shaft one hundred and eighty degrees rotated from the first cam whereby said second vertical shaft vertically reciprocates oppositely from said first vertical shaft, and said first and third drive means operating said second cup and pair of plates one hundred and eighty degrees out of phase with said first cup and pair of plates whereby objects are alternately delivered to said first and second tables and wrapped.

8. An improved wrapping Imachine comprising a table having a planar top with an aperture therein, dispensing means for successively disposing sheets of thermoplastic pliable film across said table top aperture, a cup disposed within said table top aperture having a bar depending therefrom 'and adapted to receive an object, a motor, drive means including a cam-operated rocker arm connected between said motor and said cup bar for periodically reciprocating said cup vertically below said table top, a pair of horizontally aligned heat insulating plates mounted for reciprocation directly below said table top on opposite sides of the aperture therein, heaters mounted upon said plates, and linking means connected between said motor and said plates and including a pair of spring connected pivot links for reciprocating said plates into and out of engagement below said table top aperture in synchronism with the vertical reciprocation of said cup and thereby sealing said film about an object carried by said cup.

9. In a wrapping machine having a vertical reciprocating object-supporting member `and means for wrapping an object with a sheet of wrapping material, the combination therewith of means for conveying a plurality of objects to be wrapped to adjacent said object-supporting member, said means including a vertically disposed member, a horizontal arm carried `by said member, 'a plurality of ngers carried at the end of said arm, means for periodically rotating said shaft from a first position to a second position 15 2,656,658

' released when said fingers are over said object-supporting member.`

References Cited in the le of this patent UNITED STATES PATENTS 812,912 Ballard Feb. 20, 1906 980,329 Northmp Jan. 3, 1911 "2,349,732 Howard May 23, 1944 Grady Oct. 27, 1953

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