US2926473A

US2926473A - Wrapping machine

Info

Publication number: US2926473A
Application number: US655053A
Authority: US
Inventors: Henry L Byland
Original assignee: Us Slicing Machine Co Inc
Current assignee: U S Slicing Machine Co Inc
Priority date: 1957-04-25
Filing date: 1957-04-25
Publication date: 1960-03-01
Anticipated expiration: 1977-03-01

Description

March 1, 1960 H. L. BYLAND 2,926,473

WRAPPING MACHINE Filed April 25, 1957 9 Sheets-Sheet l INVENTOR. up 52 HENRY L. BYLAND W if March 1, 1960 H. BYLAND WRAPPING MACHINE 9 Sheets-Sheet 2 Filed April 25, 1957 NQE mm vm mm mm mm ATT'YS March 1, 1960 H. L. BYLAND WRAPPING MACHINE a Rm e N & Y

Filed April 25, 1957 foobkvat March 1, 1960 H. L. BYLAND WRAPPING MACHINE 9 Sheets-Sheet 4 Filed April 25, 1957 t. 5 B um QQE 2 INVENTOR. HENRY L. BYLAND BY QMZM- w March 1, 1960 H. BYLAND WRAPPING MACHINE 9 Sheets-Sheet 5 Filed April 25, 1957 FIG? HENRY L. BYLAND M A 5 l March 1, 1960 H. L. BYLAND WRAPPING MACHINE 9 Sheets-Sheet 6 Filed April 25, 1957 H1 Al FIG. IO

INVENTOR: HENRY L. BYLAND BY 24 7 MLAM ATT'YS March 1, 1960 H. L. BYLAND WRAPPING MACHINE 9 Sheets-Sheet 7 Filed April 25, 1957 INVENTOR. HENRY L. BYLAND March 1, 1960 Filed April 25, 1957 FIG, I7

H.L.BYLAND WRAPPING MACHINE 9 Sheets-Sheet 8 HVVENTUR:

HENRY L. BYLAND BY WWZMKJ ATT'YS March 1, 1960 H. L. BYLAND 2,926,473

WRAPPING MACHINE Filed April 25, 1957 9 Sheets-Sheet -9 INVENTOR. HENRY L. BYLAND BY W/MJWLM ATT'YS 2,925,473 WRAPPING MACHINE Henry L. Byland, Deerfield, Ill., assignor to US. Slicing Machine Company, Inc., La Porte, Ind., a corporation of Indiana Application April 25, 1957, Serial No. 655,053 22 Claims. '(Cl. 53- 230 tubular fashion and tack-sealed on the bottom in a} manner heretofore well known and what constitutes the first step of the well known diamond wrap or square wrap. The tray is then placed at the infeed side of the machine with the axis of the flaps extending normal to the direction of feed. A conveyer advances the packago through a tucking and folding unit which tucksthe *nited States Patent 2,926,473 Fatented Mar. 1, 1960 Wrapping machines developed heretofore have necessitated the use of reciprocating members to effect the downward folding of the side flaps thereby necessitating such an operation to be performed at a rest station. ror'example, one known wrapping machine employs an elevator to raise the package between opposed members and push down the side fiaps, while another known wrapping machine employs vertically movable folding plates which drop along the side of the package and pull down the end flaps. Whenever an'operation is performed on an item at a rest station, as explained in these examples, the period of time for the entire wrapping operation is prolonged. Further, known machines are objectionable from the standpoint of handling various tray and card widths, wherein the adjusting of the ,machine to handle another width requires manipulation of several controls on the machine, and in some cases, the substitution of larger or smaller parts,- Still further difficulty has been encountered in tightly wrapping the package and sealing the flaps to the bottom thereof.

Accordingly, it is an object of this invention to provide a new and novel machine for wrapping and pre-packaging side flaps and effects a downward folding thereof while the package is being moved therethrough by the conveyer. From the tucking and folding unit, the package is advanced into a side and bottom-sealer unit which grips the downwardly folded side flaps, draws them tightly underneath the bottom, of the package, heat-seals the folds of the flaps and "a portion of a'fiap beneath the bottom of the package. *A second'conyeyer advances the package over a bottom V-shaped folder which folds the remaining portions of the flaps against the bottom of the package before it is advanced over a heat-sealer bar :and is discharged to a receiving. table for further distribution. Y

An important feature ofthe invention is the tucking 'and folding unit which includes a front tucker for tuckingthe leading edges of the flaps, a rear tucker for tucking the trailing edges of the flaps, upper and lower a overlapping folding plates for folding the flaps downwardly, and a set of auxiliary feed" rolls for advancing the lower-ends of the flaps faster than the conveyer can travel to assure the substantial centering of the flaps with :respect to the package. A pair of gathering rollers are mounted ahead of the tucking unit for holding down the "flaps on high packages and guiding the flaps into the folding plates. This arrangement is unique, since the tucking and folding operations are accomplished while the package is in motion as it is being advanced through :the folding and tucking unit.

It is also an important feature of the invention to 'provide a tightly wrapped package which may be achieved 'by the side sealing unit into which the package is con- *veyed after it leaves the folding and tucking unit. The

:side flaps are sealed, stretched around the package and partially sealed to the bottom. of the package before being advanced to the bottom folder and sealer.

A further important feature of the invention is in its versatility to wrap. loaded trays or pans of varying heights and widths and loaded cards or boards of various plished by 'a single control.

trays and cards having food supported thereon, wherein a tightly wrapped, neat, heat-sealed package is obtained. A further object of this invention is in the provision of a-.wrapping machine for automatically folding and sealing the flaps of a package to producea tightly wrapped and sealed package.

Still a further object of this invention resides in the provisionof'a wrapping machine havinga single control to effect adjustment accommodating-variouswidths of traysand cards of a given height, and in accommodating trays of various heights.

Another object of this invention is to provide an emcient wrapping machine having a small number of recip-' rocating members which speeds up the overall wrapping operation and enables a greater number of packages to be wrapped within a given period of time.

Still another object of this invention is in the provision of a folding and tucking unit capable of permitting straight through operation, wherein the folding and tucking steps are effected while the packageismoving.

Still another object of this invention resides in the provision of an improved side sealing unit, wherein the wrapping material is stretched tightly over the package during the side sealing operation, and a portion of the side flaps are heat-sealed to the bottomof the package. a

A further object of this in ven tion is to provide means ahead of the folding and ing unit for urging downward the side flaps as they move into the mouth of the overlapping folding plates, which means is especially effective on high packages.

A further object consists in the provision of a new and improved method for tucking and folding the side flaps of a package while the package is in motion, and in stretching the wrapping material over the package during the side sealing operation.

Other objects, features, and advantages of the inventiongwill be apparent from the following detailed disclosure, taken in conjunction with the accompanying sheets of drawings, wherein like reference numerals .refer to like parts, in which:

Fig. 1 is a perspective view looking down on the machine and in the direction of movement of the conveyers;

Fig. 2 is a partially broken and fragmentary top plan view of the wrapping machine according to the invention,

with some parts removed for purposes of clarity;

Fig. 3 is a partially broken side elevational view of the wrapping machine of the invention showing some parts in section and other parts in elevation;

Fig. 4 is a more or less diagrammatic view of the operating components of the machine with the housing and other parts removed;

Fig. 5 is a top plan view of one side of the folding and tucking unit, with some parts omitted, and looking generally along line 5-5 of Fig. 3 and in the direction of the arrows;

Fig. 6 is a transverse sectional View, taken substantially along line 6-6 of Fig. 3

Fig. 7 is a transverse sectional view, with in elevation, taken along line 77 of Fig. 3;

Fig. 8 is a transverse sectionalview, with some parts in elevation and illustrating the package in phantom, and taken substantially along line 8-8 of Fig. 3;

Fig. 9 is a view similar to Fig. 8 with the movable parts in a different position;

Fig. 10 is a fragmentary view illustrating some of the parts of the side sealing unit of Figs. 8 and 9 in still another position during the side sealing and stretching operations of the unit;

Fig. 11 is a detailed sectional view, taken substantially along line 11-11 ofFig.-8; i

Figs. 12 through 25, inclusive, are perpective views illustrating the operational steps accomplished by the machine of the present invention during the tucking, folding, and heat-sealing of the side flaps to the package; and

Fig. 26 is a perspective view of the hold-down device mounted over the heat-sealer bar adjacent the discharge end of the machine.

some parts The machine in general spasms The first conveyer includes a pair of endless members 22 having aligned pushing lugs 23 mounted thereon which engage the trailing end of the package as seen in Fig. 1. These endless members may be chains, such as illustrated, or any other suitable type of endless member, and are trained around longitudinally spaced rotatable wheels or

sprockets

24 and 25, Figs. 3, 4, and 7. The sprockets The particular construction herein illustrated, for the purpose of illustrating the wrapping machine of the present invention, is shown in wrapping a tray or pan loaded with food, but the wrapping of cards or boards with food thereon is also included. Themachine of the present inventionincludes generally a delivery table 10 upon which I the partially wrapped package is initially arranged, a folding and tucking unit 11 for folding the side flaps down and tucking the flaps, a side sealing unit 12 for tightly sealing the wrapping material about the package, a bottomfolding and sealing unit 13 for folding and sealing the flaps tightly over the bottom of the package, and a receiving table 14 for receiving the completely wrapped package, Figs. 1, 2, and 3. A package such as that shown in Fig. 11 is advanced along the delivery table and through the tucking and folding unit 11 which tucks the side flaps and folds them downwardly, Fig. 21. The packages are then moved to the side sealing unit 12 for sealing the folds of the flaps together and a portion of the flaps to the opposite sides ofthe package, Fig. 23. The package is then conveyed to the bottom folding and sealing unit 13 and to the delivery table 14 for subsequent distribution.

The various operational units of the machine are generally supported on a central cabinet structure also serving as a supporting structure and having

opposite side walls

15 and 16, and front and back walls 17and 18, respectively, all suitably connected together and reinforced to define a rigid and durable framework for the machine, as well as enclosing several moving parts thereof. It may be noted that the receiving table 10 is suitably secured to the front wall 17 whilethe delivery table 14 is removably secured to the rear wall 18 and at a lower level thereof. In order to enhance the movability of the entire machine so that it maybe easily moved along a floor from one place to another place, it is mounted on a plurality of casters 19, Figs. land 3. The packages are advanced from the receiving table 10 and through the machine to the delivery table 14 by a first conveyer 20'and. a second conveyer 21. The first conveyer advances the packages from the receiving table 10 and on through the tucking and folding unit 11 and deposits the packagein the side sealing unit 12, while the second conveyer adyances the package from the side sealing ,unitthrough the bottom folding and sealing unit 13 and to the receiving table 14. a

24 are rotatably carried on a shaft 26 horizontally disposed at the head end of the delivery table 10, while the sprockets 25 are carried on a shaft 27 positioned at the rear end or the folding and tucking unit 11 and the front end of the side sealing unit 12.

The head shaft 26 is rotatably mounted in bearings 28, Fig. 3 which are carried on an adjustable tensioning device 29 controlled by knobs 30, Figs. 1 and 3 for properly tensioning the endless members 22. The tensioning device will be mounted on a stationary part of the framework enclosed within the receiving table housing. Similarly, the shaft 27 is rotatably carried in bearing members 31, 'Fig. 7, mounted on a stationary portion of the framework within the main cabinet housing. The con veyer 20 advances the packages along asupporting strip or table 32 which extends along the receiving table 10 and through the folding and tucking unit 11, and is suitably supported by the stationary framework of the machine. A pair of parallel guide rails 33, one on the outside of each endless member 22, extend along the receiving table 10 to guide the'package into the moving and tucking unit 11. These guide rails are'adjustably mounted, as will be more clearly explained hereinafter in order to accommodate various widths ofgtrays or cards. 7

In order to drive the conveyer 29, ,a sprocket or pulley 34 is mounted on the rear shaft '27 to co-rotate therewith, and engages an endless member 35, such as a chain or belt which is also trained around a sprocket or pulley 36 carried on a main drive shaft 37, Fig. 4, which extends transversely of the machine and is suitably supported be tween the sidewalls l5 and i6.

Also mounted on the main drive shaft 37 is a gear wheel '38 which meshes with a smaller pinion gear 39 on a second intermediate shaft 40, Figs. 3 and 4. This second shaft 40 is also suitably mounted between the opposite side walls 15- and 16 of the main cabinet housing. The shaft 40 carries a pulley .41 connected to a motor pulley 42' through 'a suitable endless belt 43. The motor pulley 42 iscarried on a motor shaft 44 of a motor 45. Themotor 45 is supported one. base 46, Fig. 3, pivoted .at'one endat {7 to the frame of the main cabinet housing.

The weight of the motor 45 swings the motor around the pivot 47 and maintains the proper tension on the belt 43.

It will be noted that the sizes ,of the pulleys 41am] 42,

and the

gears

38 and 39 are such ,as to effect a speed reduction between the motor shaft 44 and the main drive shaft 37. The motor 45 constitutes the sole power source for moving all of the movable parts of the machine;.and all of the movable parts are operated from the main drive shaft 37 in synchronism.

Referring to Fig. 12, a tray 48 is shown with a shee of wrapping material 49 arranged therearound. The

zirays are generally of a relatively stiff paper, such as cardboard, with upwardly sloping sides and a peripheral In initially fashioning the diamond wrap, the sheet of wrapping material 49 is manually arranged around the tray 48,;so that the diagonal corners of the sheet are in overlapping relationship on the bottom of the tray "and the-sheet forms a tube around the tray with oppositely extending side flaps 50 extending from opposite sides of the tray.' T hegtray with the wrapping material arranged'therearcund is then passed over'a heated seal- -10, Fig. 1, to tack-seal the overlapping diagonal corner portions together on the bottom of the tray, this step being illustrated by Fig. 13. As seen in Figs. 1, 2, and 3, the sealer bar 51 is mounted at the infeed side of the receiving table 10 and the conveyer 20 and at an elevated position above the conveyer bed by the casing 52. This is obviously a very convenient position to mount the sealer bar for quick access to the wrapping machine, and enables the tray with the material to be arranged therearound to he slipped directly onto the conveyer 20. As.

seen in Fig. l, the package is arranged so that the longitudinal axes of the side or end flaps 50 of the package extend transversely of the machine and the direction of movement of thelconveyer 20. Further, it. will be noted that-the opposite side walls of the tray 48 are positioned between the guide rails 33 so that the package may be guidedly advanced along-the supporting strip 32 to assure proper positioning of the tray and side fiaps'when they enter the folding and tucking unit 11.

The folding and tuckingunit such as that illustrated in Figs. 14 and 15 since the side flaps could not be properly fed to the holding and tuck-1 ing unit. This problem is overcome by the present invention,.wherein a pair of transversely spaced power driven gathering rollers 54, Figs. 1, 2, 3, and 5 are mounted in superposed position above the conveyer and immediately ahead of the folding and tucking unit 1 1. These rollers are coaxially mounted and spaced from one another so as to engage the upper side of the and drivingly connected to a rearwardly spaced sprocket 65 carried on a stub shaft 66 by an endless chain 67,

Figs. 3, 4, 5, and 6. The stubshaft 66 is journalled in a bearing bracket 68, Fig, 5, which is supported on an inwardly'turned portion of the vertical frame member 59 by welding or other suitable means. A miter or bevel gear 69 is carried on the inner end of the stub shaft 66 and in meshing engagement with a s'econd miter or bevel gear 70 displaced 90 from the first miter gear and carried on the vertical shaft 71, Figs. 4, 5, and 7. Theopposite ends of the shaft 71 are suitably journalled in parallel spaced upper and lower frame members '72 and 73, Figs. 6 and 7, which extend inwardly from the top and bottom edges of the vertical frame member 59. The shaft 71 carries a sprocket 74 which is driven by a sprocket 75 through an endless chain 76. The sprocket 75 is carried on a verticalshaft 77 spaced rearwardly from the shaft 71, Figs. 3, 4, and 5, and rotatably supported by hearing brackets 78, 79, and 80, Fig. 3. The bearing bracket 78 is integral with the upper frame mem; ber 72., and the bearing bracket 79 is suitably secured to the inwardly turned portion of the vertical frame member 59, Fig. 5. a

After the leading edges of the package flaps travel beyond the gathering rollers 54, each contacts a downwardly sloping guide 81 which is integrally connected to an upper folding plate 82. This plate 82 is secured along its top edge to the inner end of the frame member 72, Fig. 6. The action of the guide 81 is illustrated in Fig. 16. While this guide is integrally connected with the upper folding plate 82,'it may be a separate bar if desired,

Each upper folding plate 82 coacts with a lower folding plate 83 attached at its bottom edge to the inner end of the lower frame member 73, Fig. 6, and extending upwardly with its upper edge overlapping the lower edge of the upper folding plate82 and on the inside face thereof but in slightly spaced relationship therewith. At.the forcellophane wrapper at the inner end of the side flaps I 50 as seen in Fig. 14.

The gathering rollers 54 are preferably constructe of a resilient material, such as rubber to cushion the effective contact with the cellophane and prevent tearing thereof as well as to generate a frictional contact with the cellophane. The linear speed at the periphery.

is transmitted to the package against the action of the' conveyer pushing lugs 23 which would disrupt the wrapping process, and possibly tear the cellophane.

Each gatheringroller 54 is mounted on a stub shaft which is journ'alled in. the outer free end of a swingable supporting arm 56, Fig. 5. The other end of the supporting arm is pivotally carried on a shaft 57 spaced rearwardly and parallel to the stub shaft 55 and cantileverly carried in a bearing bracket 58. The bearing bracket 58 is rigidly secured to the inner face of a vertical frame member 59 of the tucking and folding unit 11, Figs. 5 and 6. .1 The roller supporting arms 56 are angularly related to the longitudinal axis of the machine, Figs. 2 and 5, and rest intermediately on a stop 69, Fig. 3, suitably connected to the frame of the unit tolimit the downward movement of the roller while allowing the roller to swing around the shaft 57 in an upward direction should the height of the package so demand.

.Driving of each roller 54 is accomplished through a chain and sprocket arrangement including a sprocket 61, Figs. 3, 4, and 5 mounted on the roller shaft 55 and driven by a sprocket62 carried on the shaft 57 through an endless chain 63. A second sprocket 64 is also mounted on the shaft 57 coaxial with the sprocket 62 ward end of each lower, folding plate, a fronttucker 84 is sloped upwardly from front to rear, Fig. 3, terminating at a point ahead of the point where the upper edge of the lower folding plate crosses the downwardly sloping guide 81 of the upper folding plate, and serves to tuck the leading edge portions of the package flaps 50.

Before'the leading edge portions of the side flaps 50 are engaged by the front tucker 84, they are contacted by upper and lower rear tucker rollers 85 and'86, re-

' spectively, which coact to tuck thetrailing portions of the driven shaft. As seen in Fig. 6 it will be noted that when the upper and lower rollers and 86 are in coacting position, the peripheral edge along the larger diameter of the lower roller is substantially aligned on a horizontal plane withrespect' to the upper edge of the lower folding plates 83 and accordingly aligned with the side flaps 50. The upper horizontal edge of each lower folding plate 83 is also substantially in line with the bottom edge of the flange on the tray 48.

Each lower rear tucking roller 86 is rotatably carried on a pin 87 mounted to an arm 88 of a'bell crank 89, Fig. 3. The arm 88 normally extends horizontally, while the arm 90 normally extends vertically and the bell crank is pivotally mounted at 91 to the free end of a bracket support 92 which is secured to the upstanding vertical frame member 59, Fig. 5. Thus, it will be seen that oscillation of the bell cranks 89 move the lower rear tucking rollers 86 into and out of coaction with the upper rear tucking rollers 85.

Thus, the upper roller 85, which is power driven, drives the lower roller 86. It may be appreciated that the flaps aaaaere move in the same direction as the rollers; and therefore, to trick the trailing portions of each fiap, it is necessary to drive the rollers at a speed greater than the speed of the conveyor. In order to obtain the best possible tucking action, it is also desirable to slip the material at the underside of the flaps under faster. To accomplish this action, the upper rollers 85 are beveled at 85a, this also relieving the upper part of the flaps from being gripped at the inner portions nearest the package. Further, the upper rollers being larger effects driving of the lower rollers at a higher speed. Hence, the inner parts of the lower rollers which are not engaged by the upper roller effects faster slipping under of the material of the flaps.

In order to impart oscillation to the bell cranks 89, the outer end of each arm 90 is pivotally secured to one end of an intermediate link 93 at 94. The other end of the links slidably pivot on a cross rod 96, Figs. 3, and 6. The slidable pivot is necessary in order to compensate for vertical adjustment of the folding and tucking unit 11 as will be hereinafter more clearly described. The crossrod 96 is pivotally supported at opposite ends by links 95 and 95a, Fig. 6, which are, in turn, pivoted to across shaft 99 mounted at opposite ends in

bearings

100, 100 secured to the front wall 17. The link 95 carries an extension which is connected to a cam follower 97 by a pivot 98. The cam follower 97 is in the form of an elongated bar with the endopposite the end connected at 98 to the bar 95 being bifurcated and slidably received on the drive shaft 37. Between the ends of the cam follower 97 is a roller 101 which is received by a cam track 102a of a cam wheel 102 secured to and rotatable with the drive shaft 37, Fig. 4. The cam track is arranged so that the bite between the upper and lower rear tucker rollers opens to receive the leading edge portions of the flaps 50 and to close shortly after the flaps have entered between the bite thereof. Therefore, it is seen that the movement of the lower rear tucker rollers 86 is timed with the movement of the infeed conveyer 20, and particularly with the positioning of the lugs 23 on the conveyor chains. In Fig. 18, the movement of the tucker rollers 86 'is expressed by the arrows 103,'wherein the rollers move from the dotted line position to the solid line position for engaging the flaps 50 of the package.

The subsequent coaction between the downwardly sloping guide 81 on the upper plates 82 and the horizontal upper edge 104, Fig. 20, of each lower folding plate 83 serves to aid in gradually folding the flaps of the package downwardly until the flaps take a substantially vertical position with respect to the package as seen in Fig. 19.

Because the overlapping folding plates will effect a friction drag on the side flaps of the package which will cause the flaps tolag behind the movement of the package as the conveyer advances the package through the tucking unit, means are provided to advance the lower ends of the flaps at a speed faster than the movement of the package. This means includes a power driven auxiliary feed roll 105, Fig. 7, rotatable about a vertical axis at opposite sides of the tucking plates to coact with the lower tucking plates 83 and engage the side flaps therebetween. Preferably, these auxiliary feed rollers are made of rubber in order to increase their frictional contact with the side flaps and to compensate forvarions thicknesses of packaging materials. These auxiliary fee-:l rolls are also driven at a higher speed than the conveyor 21 in order to compensate for the lag of the flaps caused by the frictional contact with the tucking plate and to slightly advance the flaps-ahead of the package as they leave the tucking unit. As seen most clearly in Fig. 7, the auxiliary feed rolls 105 are mounted on the vertical power driven shafts 71 and are arranged below the lower edges of the upper folding plates 82. These side flaps of'the package are thereby properly arranged with respect to the package when the package is delivered from'the tucking unit 11 into the side sealing unit 12 whereby the flaps may then be properly folded underneath. the bet; tom of the package and sealed thereto.

Each side of the tucking unit is mounted on a longitudinally extending anglebar 106, Figs. 6 and 7, which has downwardly extending lugs 107 mounting rigidly thereon nuts 108. These nuts 108 are threadedlyreceived on a transversely extending and adjusting rod 109 having threading of one hand at 110 and threading of the other hand at 111, Fig. 7. The rod 109 is suitably journalled in'bearing's carried by the

opposite end walls

15 and 16, the rod extends outwardly beyond one of the end walls to receive a crank handle 112 This arrangement is provided since it is desirable that the wrapping machine of this invention be adaptable to handle many different sized trays or pans for wrapping materials therein.

"A vertically extending tubular support 113 is slidably received on a cylindrical bar 114 in each side of the tucking unit. The lower end of each tubular support is rigidly secured to a corresponding angle bar by a bracket 115, while the upper end carriesa nut 116 thereon which receives a threaded screw member 117. Each screw member is mounted in the upper frame member 72 for rotation therewith, but arranged to preclude axial movement therewith, and carries a knurled knob 118 at the outside of the frame member. As seen in Fig. 2, a second transversely extending rod 119 is mounted at the opposite side walls, and is drivingly connected to the first rod 109 by means of an endless member, such as a chain 120 trained over a sprocket 121 on the rod 109 and a sprocket 122 on the rod 119. Although not shown, the rod 119 is also threaded to coact with nuts connected to the angle bars 106 by means of lugs.

Accordingly, rota-tion of the crank 112 imparts movement to the nuts 103, the lugs 107 and the angle bars 166 in opposite directions to either move the opposed tucking components toward each other or away'from each otherdepending upon the width of the pan or tray desired to be wrapped. The guide rails 33, are also secured to the angle bars 106 and accordingly are adjusted during a width adjustment. This action takes place'because of the opposite threads on the

rods

109 and 119. It will be noted that the conveyer chains 22 and the supporting'strip or table 32 remain stationary during adjustment of the opposing tucking components, and that it is not necessary that these latter elements be adjustable in any manner inorder to effect -width adjustment for the tucking unit. Because of the slidable connection between links 93 and the shaft 96, Figs. 3 and 6, it will be seen that the'bell crank 89 and'its associated linkages with respect to the lower movable tucking-rollers 86 will slide along the shaft 96 when adjustmentsare made by the operation of the

rods

109 and 119.

Since it is also desirable that the wrapping machine of the present invention be adaptable to handle pans and trays of different heights for wrapping thereof, it is therefore necessary to provide an adjustment whereby the components of the tucking unit may be raised or lowered relative to the stationary supporting table 32 and the conveyer elements or chains 22. Accordingly/[the entire group of tucking components on each side may be raised or lowered by manipulation of the threaded screw members 117 as operated by the knobs 11S. Rotation of the screw members 117 in one direction causes the vertical frame members 59 and the upper frame members 72 and the lower frame members 73, all of which mount the various tucking components, to be elevated, whereby the bar 114 slides within the tubular supports 113 held on the anglebars 106. Rotation of the screw members 117 in opposite directions causes all of the frame members to be lowered with the tucking components in order to take a tray or pan of lesser depth. Generally, the lip around the pan will be positio ned so that it rides ove'r the top edgeof the lower folding plates 83, and the bot tom of the pan'will then ride on'the supporting'table 32. SQ s e de th t ze y be me gr a it e e srv,

Side sealing unit The lugs 23 on the'conveyer 22 will effect feeding of the package from the tucking unit 11 into the side sealing unit 12. In the side sealing unit 12'; the package is received on and supported by the upper longitudinal edges of spaced inner gripping elements 123, Figs. 9 and 21. The now tucked flaps 50, extending substantially in a vertical direction enter between the inner gripping elements 123 and outer gripping elements or heating shoes I 124. These heating shoes will be generally energized and heated to a temperature suitable for heat sealing the cellophane in the final wrapping steps. age has been received as seen in Figs. 8 and 20 in the side sealing unit 12, the heating shoesmove inwardly and upwardly along an arcuate path, coming in slightly below the package bottom and then lifting the package to raise it from the inner gripping elements and thereby assure that the package bottom rests on the top of the hot heating shoes 124 to effect a better seal and to seal that portion of the cellophane to the bottom of the package. As the heating shoe is moved inwardly, the side flaps 50 of the package are folded until they approximate the contour After the pack shown in Figs. 10 and 23, wherein a portion of the flaps has been bent inwardly and against the bottom of the .package and another portion of the flaps remains in a substantially vertical position. After the shoes engage the bottom of the package they completely support the package until it is moved from the shoes by the second conveyer 21. But before the package is moved from 1O at one end to the cross bar 138 and at the other end to the lever 140 while the bar 1391: is pivoted at one end to the bar 138. A cam follower 142 is carried on the cam lever 140 and coacts with a cam track 143 formed in the cam wheel 139. The end of the cam lever 140 opposite lts'plvotal connection to .the bell crank 139 is bifurcated for slidable relation over the drive shaft 37 which-thereby permits only substantially reciprocating movement of the cam lever140. Inasmuch as the cam lever 140 which operates the cam linkages ofthe side sealing unit,

is operated from the drive shaft 37 which also operates the tucking rollers-=86 inthe tucking unit, these elements are arranged'in timed relation to act synchronously with each other. Further, the tucking unit and side sealing unit are arranged in timed relationship with respect to the conveyer 20 which is also driven from the drive shaft 37. i 1

Since. it is desirable to efiect a tight wrapping of the cellophane around the package, the heating shoes 124 and theinner gripping elements 123 initially grip the side flaps 50 of the package a slight distance under the bottom of the package, as seen most clearly in Fig. 21, and then pull the side flaps tightly underneath the package until the heating shoes 124 have lifted the package above the inner gripping elements 123, as seen more clearly in Fig. 9. By virtue of the early gripping action effected by the heating shoes 124 and the inner gripping elements 123, the cellophane will be pulled taut around the package and' sealed thereto. The action takesplace with respect to the side flaps as soon as'the heating shoes 124 begin to apply pressure against the flaps in coaction with the shoes, the inner gripping elements 123 are moved slightly inwardly in order to release the grip on the side flaps with respect to the outer gripping elements or heating shoes 124. I

The inner gripping elements are pivotally mounted at their lower ends to horizontally extending bars 25 which end of each spring 128 is connected to the plates 126 and the other end to the inner gripping elements 123.

The inward and upward arcuate movement of the shoes 124 is accomplished by a parallelogram linkage arrangement which includes an upper bar 130 having the shoes connected to the inner ends thereof and being pivotally connected to

parallel links

131 and 132. The

parallel links

131 and 132 are also similarly pivotally connected to the lower stationary bars 125. Specifically, each inner link 131 is pivoted at its upper end to the horizontally ex' tending upper bar 130 at 133 and secured to a longitudinally extending shaft 134 pivotally carried in the lower stationary bars 125.

Similarly, the links 32 are pivotally connected at their upper ends to the horizontal bar 120 by a longitudinally extending shaft 135, while the lower ends are pivotally connected to the lower bars 125 at 135a.

The parallelogram linkages are operatedby actuating levers 136 rigidly secured at one end to the shaft 134 and pivotally mounted at the other end to blocks 137, Figs. 8, 9, and 11, which are slidably received on a square cross bar 138. This cross bar 138 is oscillated up and down by a cam'wheel 139 mounted on the drive shaft 37, Fig. 4, through a bell crank 139a, a bar 13% and a cam actuated lever 1411-. Thebell crank 139a and the bar 13% are carried on a shaft 141 mounted on the the inner gripping elements 123. The inner gripping elements are pivoted. inwardly to an inward position as seen in Fig. 10 by the movement of the heating shoes 124. Normally, the inner gripping elements 123 will assume a position such as that shown in Fig. 9, and will then move inwardly against the force of the springs 128. This force may be adjusted by utilization of different size springs 128. When the heating shoes 124 have reached the properly desired inward position and perform the desired sealing and tightening operations on the package, wherein the upper portions of the side flaps are then sealed to the bottom of the package, further inward movement of the'heating shoes effects a releasing of the gripping action by a faster inward movement of the inner gripping elements 123. This is accomplished by adjustable cam followers 144 carried by the links 131 of the parallelogram linkage, Figs. 8 and 9, which are spaced above the shafts 134 or lower pivot points of the links 131, and engage cam plates 144a secured. to the gripping elements 123. As the rollers travel over the inclined cam surface of the cam plates, a fast inward movement of the gripping elements is obtained. Since the rollers 144 follow apath along an arc having a radius extending from the shaft 134 to the outer end of the pin,

the latter'of'which engages the cam plates on the inner gripping elements'123, and the heating shoes move along an arcuate path about the shaft 134 which also has an upward component because of the parallelogram linkage, the rollers will therefore move faster along the arcuate path so that further inward movement of the shoes 124 after they reach a certain point causes the inner gripping elements to be moved away quickly from the heating shoes andthereby release the gripping action on the side flaps 50 of the package.

Since it is also necessary that the side sealing unit be adjusted for varying widths of pans adapted to be Wrap'pedin the'machine, and since it has already been explained that the opposing heating shoes and components are mounted. on the transversely spaced angle bars 106, adjustment of the machine for a different width of pan or tray will effect simultaneous adjustment in the sidesealing unit. And for this reason, the blocks 137 are slidably associated with the cross bar 138 and will Bottom folding sealing unit Upon release of the package side flaps 50 in the side sealing unit 12, lugs 145, Figs. 2 and 4, preferably of a resilient or rubber material, are brought to bear behind the package and to'carr'y or advance the package from the side sealing unit. These logs 145 are mounted on endless carryirig members or chains 146 of the conveyer 21, these chains being trained around longitudinally spaced sprockets 147'and 148, Figs. 2 and-4, whichare arranged to support the runs of the chains 146 in a horizontal plane, as seen in Fig. 2. sprockets 147 are carried on the vertical shaft '77, Fig. 3, mounted in association with'the tucking unit 11, while the rear sprockets 148 are mounted on vertical shafts 149. The vertical shafts 149 are carried in bearing supports 150, Fig. 3, which are rigidly secured to the spaced angle bars 106, and accordingly moved therewith on adjustment of the machine for handling various widthsof pans or trays. Both vertical shafts 149 are drivingly connected to a transversely extending horizontal shaft 151, Figs. 2 and 4, which is bearingly supported at opposite ends in the oppositeend walls and 16 of the machine. Elements drivingly connecting

shafts

149 and 151 includes a sprocket 152 on each vertical'shaft 149 and an endless drive member or chain 153 trained over the sprocket 152 and a sprocket 154 mounted on a vertical shaft 155, Fig. 4. Each vertical shaft 155 is suitably supported in a bearing bracket 156, Fig. 3. A miter'gear 157 is carried on the shaft 155 and in meshing engagement with a miter gear 158 carried onthe cross shaft 151. The miter gear 158 on the shaft 151 is arranged so that it will co-rotate with the shaft 151, but may be slidably moved therealong during the adjustment of the machine. 'Accordingly,'shaft 151 may be splined. To further support the miter gear 158 and assu're'its meshing engagement with the miter gear 157 and proper movement along the shaft 151, a bracket 159 is attached thereto and to each angle bar 106, Fig. 2.

As seen in Fig. 4, the shaft-151 is drivinglyconnected to the power shaft 37 by means of a sprocket-160 'r'nounted on the shaft 151, a sprocket 161 carried on the power shaft 37, and an endless transmission member such as a chain 162 trained over said sprockets. 'A chain tightening pulley 163 is suitably carried by the machineframe foh adjusting the tension in the chain 162:. Since the conveyor 21 is also driven from the main power shaft 37, it is synchronized in timed relationshipwith the first conveyer, the tucking unit and the side sealing unit so that all of the operations are performed in synchronized relationship.

The lugs 145 on the conveyer 21 push the package alongthe transversely spaced supporting bars 164, Fig. 2, mounted on upstanding standards 165 which are'carried on the angle bars 106. Accordingly the spacing of the I supporting bars 164 varies in accordance with the spacing in the tucking and side sealing units when width adjustments are made to the machine. As seen most clearly in Fig. 2, the supports are spaced apart at least a distance so. that the flaps 50 are freely received therebetween.

The flaps on the package are further folded inwardly to the bottom of the package by a bottom folding plate 166 having a V-shaped side 167 facing the side sealing unit 12. The package approaches the \l-shaped side 167 of the plate 166 in the mannershown in Fig. 24. The flaps are gradually folded inwardly under the bottom of the package. The conveyer 21 continues to advance the package from the machine and over-a heated sealing plate or bar 168, Figs, 2 and 25, where the flaps are sealed to the bat e 9.5. e Pa a e, and d s h r e rac v )v a The forward by a parallelogram linkage arrangement.

weight, and therefore, the sealing of the fiaps to the bottom of these packages as they are conveyed across the heating plate 168 may be unsatisfactory; To alleviate this possible condition, hold down or presser bars 170 are mounted at opposite sides of the machine above and in the vicinity of the sealing plate 168, as seen in Figs. 1, 3, 25, and 26. These bars engage along the opposite upper edges of the packages and bias same against the heating plate to assure proper sealing action. The bars 170 are mounted on the chain guide plates 171 of the conveyer 21 This linkage arrangement includes

links

172 and 173 pivotally connected at each end of the bars and also connected to

shafts

174 and 175, respectively. Each

shaft

174 and 175 is respectively journalled in bearing supports 176 and 177 connected together by an elongated bar 177a.

Brackets

178 and 179 extend from the bearing supports 176 and 177, respectively and are provided with

slots

180 and 181, respectively. The axes of the slots are normal to the hold down bars and provide means for adjusting the bars transverse the machine if desired, although the bars would move in and out with the width adjustment of the machine. The slots receive threaded

studs

182 and 183 respectively which are carried by

upstanding supports

184 and 185 secured to the guide plates 171.

Knurled nuts

186 and 187 are received by the

studs

182 and 183, respectively, for locking the brackets and hold down bars in adjusted position. A weight bar 188 is connected to the outer end of each shaft 174 and adjustably carries thereon a weight 189. This weight, adjustable along the weight bar, transmits weight to the hold down bar through the weight bar 188, the shaft 174, and the link 172. In order .to prevent the hold down bar from striking the heating plate when no package is traveling thereacross, an adjustable stop 190 is carried by the weight bar 188 and arranged to engage the chain guide plate 171.

Preferably, the temperatures of the heating bar 51, the V sealing shoes 124, and the sealing plate 166 are thermo statically controlled by adjustable thermostats, not shown,

may be effected without departing from the scope of the novel concepts of the present invention, but it is understood that this application is to be limited only by the scope of the appended claims.

The invention is hereby claimed as follows:

1. In a wrapping machine adapted to receive and complete the wrapping of an article that is partially wrapped by a sheet of transparent heat-scalable material wherein side flaps extend laterally from opposite sides thereof, a horizontally extending support, longitudinally extending and transversely spaced guide bars along part of said support, conveyer means for continuously advancing the article along said support and between said guide bars, a folding and tucking unit along said support adapted to fold and tuck said side flaps, said unit comprising a front tucker tucking the leading edge portions of the fiaps, saicl front tucker including a pair of transversely spaced upwardly sloping members, a rear tucker tucking the trailing edge portions of the flaps, said rear tucker including a pair of coacting rollers, the linear speed of said rollers at the outer periphery thereof being greater than the linear speed of said conveyor, overlapping vertical plates folding the flaps downwardly along the, sides of the package, whereby the flaps are tucked and folded in one continuous operation as they are advanced continuously along the, support. j

2. In a wrapping machine adapted to receive and complete the wrapping of an article that is partially wrapped by a sheet of transparent heat-scalable material wherein side flaps extend laterally from opposite sides thereof, a horizontally extending article support, longitudinally extending and transversely; spaced guide barsalong partof said support, conveyer means for continuously advancing the article along said support and between said guide bars, the axes of said flaps extending transverse to the direction of conveyer travel, a folding and tucking unit along said support adapted to fold and tuck the side flaps, said unit comprising a first tucker for. leading edge portions of said flaps, said first tucker including a pair of transversely spaced upwardly sloping members, a second tucker for tucking the trailing edges of the side flaps, said second tucker including transversely spaced pairs ,of coacting rollers, one of said rollers of each pair being power driven, the linear speed of said rollers at the outer periphery thereof being greater than the linear speed of said-conveyer, overlapping vertical plates folding the flaps downwardly along the sides of the package, whereby the flaps are tucked and folded in one continuous operation as they are advanced continuously along the support.

3. In a wrapping machine adapted to receive and complete the Wrapping of an article that is partially wrapped by a sheet of transparent heat-scalable material wherein side flaps extend laterally from opposite sides thereof, a horizontally extending article support, longitudinally extending and transversely spaced guide bars along part of said support, conveyer means for continuously advancing the article along said support and between said 4 V v i and arranged to bend down the side flaps along the article, overlapping vertical plates folding the flaps downwardly along the sides of the package, whereby the flaps are tucked and folded in one continuous operation as they are advanced continuously along the support.

5. In a wrapping machine adapted to receive and comv plete the wrapping of an, article that is partially wrapped guide bars, the axes of said flaps extending transverse to the direction of conveyer travel, a folding andtucking members, a'second tucker for tucking the trailing edgesof the side flaps, said second tucker including transversely spaced pairs of coacting rollers, one of said rollers of each pair being power driven, the linear speed of said rollers at the outer periphery thereof being greater than the linear speed of said conveyor, the other roller of each pair being movable toward and away from said one roller in time sequence to permit the leading edge portions of the side flaps to be easily gripped thereby, and overlapping vertical plates folding the fiaps downwardly along the sides of the package, whereby the flaps are tucked and folded in one continuous operation as they are advanced continuously along the support.

4. In a wrapping machine adapted to receive and complete the wrapping of an article that is partially wrapped by a sheet of transparent heat-sealable material wherein side flaps extend laterally from opposite sides thereof, a horizontally extending article support, longitudinally extending and transversely spaced guide bars along part of said support, conveyer means for continuously advancing the article along said support and between said guide bars, the axes of said flaps extending transverse to the direction of conveyer travel, a folding and tucking unit along said support adapted to fold and tuck the side flaps, said unit comprising a first tucker for tucking the leading edge portions of said flaps, said first tucker including a pair of transversely spaced upwardly sloping members, a second tucker for tucking the trailing edges of the side flaps, said second tucker including transversely spaced pairs of coacting rollers, one of said rollers of each pair being power driven, the linear speed of said rollers at the. outer periphery thereof being greater than the linear speed of said conveyer, the other roller of each pairbeing movable toward and away from said one relief in time sequence to permit the leading edge portions of the side flaps to be easilygripped thereby, each pair of rollers having generally 'frusto-conical engaging faces by a sheet of transparent heat-sealable material wherein side flaps extend laterally from opposite sides thereof, a horizontally extending article support, longitudinally extending and transversely spaced guide bars along part of said support, conveyer means for continuously advancing the article along said support and between said guides bars, the axes of said flaps extending transverse to the direction of conveyer travel, a folding and tucking unit along said support adapted to fold and tuck the side flaps, Said unit comprising a pair of power driven transversely spaced gathering rollers suspended over said support for holding down the side flaps, the linear speed of said rollers at the-.outer periphery being greater than the speed of the conveyer, a pair'of downwardly sloping members serving to gradually force the flaps down, a first tucker for tucking the leading edge portions of said flaps, said first tucker including a pair of transversely spaced upwardly sloping members, a second tucker for tucking the trailing edges of the side flaps, said second tucker including transversely spaced pairs of coacting rollers, one of said rollers of eachpair being power driven, the linear speed of said rollers at the outer periphe'ry thereof being greater than the linear speed of said conveyer, overlapping vertical plates folding the flaps downwardly along the sides ofthe package, whereby the flaps are tucked and'folded in one continuous operation as they'are advanced continuously along the support.

6. In a wrapping machine adapted to receive and complete the wrapping of an article that is partiallywrapped by a sheet of transparent heat-sealable material wherein side flaps extend laterally from opposite sides thereof, a horizontally extending article support, longitudinally extending and transversely spaced guide bars along part of said-support, conveyer meansfor continuously advancing the article along said support and between said guide bars, the axes .of said flaps extending transverse to the direction of conveyer travel, a folding and tucking unit along said support adapted to fold and tuck the side flaps, said unit comprising a pair of power driven transversely spaced gathering rollers suspended over said support for holdingdown the side flaps, the linear speed of said rollers at the outer periphery being greater than the speed of the conveyer, said rollers being carried on arms which are pivotally mounted at one end and gravity actuated, a pair of downwardly sloping members serving to gradually force the flaps down, a first tucker for tucking the leading edge portions of saidfiaps, said first tucker including a pair of transversely spaced upwardly sloping members, a second tucker for tucking the trailing edges of the side flaps, said second tucker including transversely spaced pairs of coacting rollers, one of said rollers of each pair being power driven, the linear speed of said rollers at the outer periphery thereof being greater than the linear speed of said conveyer, overlapping vertical plates folding the flaps downwardly along the sides of the package, whereby the flaps are tucked and folded in one continuous operation as they are advanced continuously along the support.

7. In a wrapping machine adapted to receive and complete the wrapping of an article that is partially wrapped by a sheet of transparent heat-scalable material wherein side flaps extend laterally from opposite sides thereof, a

horizontally extending article support, longitudinally ex.-

tending and transversely spaced guide bars along part of i tion of conveyer travel, a folding and tucking unit along said support adapted to fold and tuck the side flaps, said unit comprising a first tucker for tucking the leading edge portions of said flaps, said first tucker including a pair of transversely spaced upwardly sloping members, a second tucker for tucking the trailing edges of the side flaps, said second tucker including transversely spaced pairs of coacting rollers, one of said rollers of each pair being power driven, the linear speed of said rollers at the outer periphery thereof beinggreater than the linear speed of said conveyor, overlapping vertical plates folding the flaps downwardly along the sides of the package, an auxiliary feed roller coacting with the lower folding plate to advance the lower ends of the fiaps at a faster rate than the conveyer, whereby the flaps are tucked and folded in one continuous operation as they are advanced continuously along the support.

8. In a wrapping machine adapted to receive and complete the wrapping of a tray or card having edible substances thereon which is-partially wrapped by a sheet of transparent heat-scalable material wherein side flaps extend laterally from opposite sides thereof, a horizontally extending support for receiving the partially wrapped item, conveyer means for continuously advancing the item along said support with the axes of the flaps extending transverse the direction of conveyer travel, a folding and tucking unit along said support adapted to fold and tuck the side flaps as they pass therethrough and a side sealing unit for sealing said side flaps and sealing a portion of the flaps to the botttom of the item, said side sealing unit including a pair of grippers, each gripper receiving a flap and having a pair of gripping elements, and

means for holding said gripping elements apart to receive the flaps and to grip the flaps and force them under the item to stretch the material about the item and effect a tightly wrapped package.

9. In a wrapping'machine adapted to receive and complete the wrapping of a tray or card having edible substances thereon which is partially wrapped by a sheet of transparent heat-scalable material wherein side flaps extend laterally from opposite sides thereof, a horizontally extending support for receiving the partially wrapped item, conveyer means for continuously advancing the item along said support with the axes of' the flaps extending transverse the direction of conveyer travel, a folding and tucking unit along said support adapted to'fold and tuck the side flaps as they pass therethrough and. a side sealing unit for sealing said side flaps and sealing a portion of theflaps to the bottom of the item, saidside sealing unit including a pairof grippers, each gripper receiving a fiapand having a pair of gripping elements, one of said gripping elements being heated to seal the flaps, and means for holding said gripping elements apart to receive the flaps and to grip the flaps and force them under the item to stretch the material about the item and effect a tightly wrapped package.

10. In a wrapping machine adapted to receive and complete the wrapping of a tray or card having edible substances thereon which is partially wrapped by a sheet of transparent heat-scalable material wherein side flaps extend laterally from opposite sides thereof, a horizontally extending support forreceiving the partially wrapped item, conveyer means for continuously advancing the item along said support with the axes of the flaps extending transverse the direction of conveyer travel, a folding and tucking unit along said support adapted to fold and tuck the side flaps as they pass'the rethrough, and a side sealing unit for sealing said side flaps and sealing a portion of the flaps to the bottom of the item, said side sealing unit including a pair of grippers, each gripper receiving a fiap and having a pair of gripping ele- ,ments, one of said gripping elements being heated to seal theflaps, and means for holding said gripping elements apart to receive the flaps and to grip the flaps and force them under the item to stretch the material about the item and effect a tightly wrapped package, said means spreading the gripping elements apart after the flaps have been'subjected to the stretching operation,

11'. In a wrapping machine adapted to receive and complete the wrapping of a tray or card having edible substances thereon which is partially wrapped by a sheet of transparent heat-scalable material wherein side flaps extend from opposite sides thereof, a side sealing unit for sealing the side flaps and sealing a portion of said flaps to the bottom of the item, said side sealing unit including a. pair of grippers, each gripper receiving a flap and having a pair of gripping elements, one of said gripping elements being heated to seal the flaps, and means for holding said gripping elements apart to receive the flaps and to grip the flaps and force them under the item to stretch the material about the item and effect a tightly wrapped package, said means spreading the gripping elements apart after the flaps have been subjected to the stretching operation.

' 12. A sidesealing unit for a wrapping machine for sealing sidefiaps of a package and sealing a portion of the side flaps to the bottom of the package, said unit comprising a pair of movable grippers, each gripper having a heated and a non-heated gripper member, said grippers being movable by a parallelogram linkage so as to initially grip the flaps and sealsame and then seal a portion of the flaps to the bottom of the package.

13. A wrapping machine comprising, a pair of transversely spaced tucking units having means for folding and tuckingside flaps of a package, a pair of side sealing units having means for stretching the flaps around the package, sealing the flaps and sealing a portion of the flaps to the bottom of the package, a sealing plate for further sealing the flaps to the bottom of the package, a continuously moving conveyer for pushing the package through the tucking units and into the sealing units, and

a second conveyer for pushing the package from the sealing units and over the sealing plate for discharge from the machine. a

14. A Wrapping machine comprising, a pair of transversely spaced tucking units having means for folding and tucking side fiaps of a package, a pair of side sealing units having means for stretching the flaps around the package, sealing the flaps and sealing a portion of the flaps to thebottom of the package, a continuously moving conveyer for pushing the package through the tucking units and into the sealing units, and a second conveyer for pushing the package from the sealing units and over the sealing plate for discharge from the machine, and drive means for synchronizing the operation of all of the parts to efficiently and quickly wrap a package.

15. A wrapping machine comprising, a pair of transversely spaced tucking units having means for folding and tucking side flaps of a package, a pair of side sealing units having means for stretching the flaps around the package, sealing the flaps and sealing a portion of the flaps to the bottom of the package, a sealing plate for further sealing the flaps to the bottom of the package, a continuously moving conveyer for pushing the package through the tucking units'and into the sealing units, and a second conveyer for pushing the package from the sealing units and over the sealing plate for discharge from the achine, said tucking units and sealing units mounted on longitudinally extending angle bars, and means for adjusting said angle bars to change the spacing between said tucking and sealing units to accommodate various sizes of packages.

16. A wrapping machine comprising, a pair of transversely spaced tucking units having means for folding and tucking side flaps of a package, a pair of side sealing units having means for stretching the flaps around the package, sealing the flaps and sealing a portion of the flaps to the bottom of the package, a sealing plate for further sealing the flaps to the bottom of the package, a continuously moving conveyer for pushing the package v1 we 17 through the tucking units and into the sealing units, and a second conveyer for pushing the package from the sealing units and over the sealing plate for discharge from the machine, said tucking units and sealing units mounted on longitudinally extending angle bars, and means for adjusting said angle bars to change the spacing between said tucking and sealing units to accommodate various sizes of packages, said means including a single hand lever for effecting the width adjustment of all parts of said machine.

17. A wrapping machine comprising a pair of transversely spaced gathering rollers engaging the top portions of the package, a pair of transversely spaced tucking units having means for folding and tucking side flaps of a package, a pair of side sealing units having means for stretching the flaps around the package, sealing the flaps and sealing a portion of the flaps to the bottom of the package, a sealing plate for further sealing the flaps to the bottom of the package, a continuously moving conveyer for pushing the package through the tucking units and into the sealing units, and a second conveyer for pushing the package from the sealing units and over the sealing plate for discharge from the machine.

18. A Wrapping machine comprising, a pair of transversely spaced tucking units having means for folding and tucking side flaps of a package, a pair of side sealing units having means for stretching the flaps around the package, sealing the flaps and sealing a portion of the flaps to the bottom of the package, a sealing plate for further sealing the flaps to the bottom of the package, means engaging the top of the package and biasing same towards the sealing plate, a continuously moving conveyer for pushing the package through the tucking units and into the sealing units, and a second conveyer for pushing the package from the sealing units and over the sealing plate for discharge from the machine.

19. A Wrapping machine adapted to fold, tuck and seal the side flaps of a package comprising, means for folding and tucking the side flaps, means for stretching the side flaps to effect a tightly wrapped package and to partially seal the fiaps to the bottom of the package, means for folding the flaps against the bottom and sealing them thereagainst, means for biasing the package against said folding and sealing means, and conveyer means for conveying the package along a rectilinear path during the wrapping operations.

20. A wrapping machine adapted to fold, tuck and seal the side flaps of a package comprising, means for folding and tucking the side flaps, a tucking and folding unit for tucking the side flaps and folding them downwardly, a side sealing and stretching unit for sealing the side flaps, stretching them over the package to effect a tight wrap, and sealing part of the flaps to the bottom of the package, a sealing and folding plate unit for further folding the flaps to the bottom of the package and sealing same thereto, means mounted in overlying relation to said sealing and folding plate unit for biasing the 18 packages thereagainst, said units being arranged in successive order so that the package may be moved along a rectilinear path through said units, and means for advancing the packages through said units.

21. A Wrapping machine adapted to fold, tuck and seal the side flaps of a package comprising, means for folding and tucking the side flaps, gathering rollers mounted ahead of said tucking and folding unit and above said packages for gathering the material forming the side flaps and urging the side flaps into position to be received by said folding and tucking unit, a tucking and folding unit for tucking the side flaps and folding them downwardly, a side sealing and stretching unit for sealing the side flaps, stretching them over the package to effect a tight wrap, and sealing part of the flaps to the I bottom of the package, a sealing and folding plate unit for further folding the flaps to the bottom of the package and sealing same thereto, means mounted in overlying relation to said sealing and folding plate unit for biasing the packages thereagainst, said units being arranged in successive order so that the package may be moved along a rectilinear path through said units, and means for advancing the packages through said units.

22. In a wrapping machine adapted to receive and complete the wrapping of a tray or card havingedible substances thereon which is partially wrapped by a sheet of transparent heat-scalable material wherein side flaps extend laterally from opposite sides thereof, a horizontally extending support for receiving the partially wrapped item, conveyer means for continuously advancing the item along said support with the axes of the flaps extending transverse the direction of conveyer travel, a folding and tucking unit along said support adapted to fold and tuck the side flaps as they pass therethrough, and a side sealing unit for sealing said side flaps and sealing a portion of the flaps to the bottom of the item, said side sealing unit including means for engaging the side flaps and stretching them about the item to effect a tightly wrapped package.

References Cited in the file of this patent UNITED STATES PATENTS 1,646,497 Sandberg Oct. 25, 1927 1,834,997 Beatty i Dec. 8, 193-1 2,037,631 Hultin Apr. 14, 1936 2,050,268 Bronander Aug. 11, 1936 2,246,268 Smith June 17, 1941 2,304,048 Jensen Dec. 1, 1942 2,604,744 Klimas July 29, 1952 2,605,597 Scheib Aug. 5, 1952 2,652,669 Holtz Sept. 22, 1953 2,745,234 Schooler 2 May 15, 1956 2,801,508 Prince Aug. 8, 1957 2,874,527 Cravits Feb. 24, 1959 FOREIGN PATENTS I 57,874 Switzerland Aug. 14, 1911