US3478488A

US3478488A - Packaging machine

Info

Publication number: US3478488A
Application number: US626297A
Authority: US
Inventors: Hans A Jensen; Myron J Merdler
Original assignee: Oscar Mayer Foods Corp
Current assignee: Oscar Mayer Foods Corp
Priority date: 1967-03-27
Filing date: 1967-03-27
Publication date: 1969-11-18
Anticipated expiration: 1986-11-18

Description

Nov. 18, 1969 A, JENSEN E1- AL 3,478,488

PACKAGING MACHINE 6 Sheets-Sheet 1 Filed March 27, 1967 N SE RS m 0N E J N E A MAM S WANHN 0 Y Nov. 18, 1969 Filed March 27, 1967 H. A. JENSEN ET AL 3,478,488

PACKAGING MACHINE 6 Sheets-Sheet 2 I *0 Q) i Fifi-4 I F 11 l s k x 4 k Ir LI INVENTORS HANS A. JENSEN ATT 'YS.

NOV. 18, 1969 A, JENSEN ET AL 3,478,488

PACKAGING MACHINE 6 Sheets-Sheet 5 Filed March 27, 1967 \\ns n6.

w way smm w m wER T NJE A E A M m- Ami Yl M. A I w w B Nov. 18, 1969 H, A, JENSEN ET AL 3,478,488

PACKAGING MACHINE Filed March 2.7, 1967 6 Sheets-Sheet 4 IN VENTORS HA NS A. JENSEN MYRON J. M DLER BY ATT'Y Nov. 18, 1969 H. A. JENSEN E AL 3,478,438

PACKAGING MACHINE Filed March 27, 1967 r 6 Sheets-Sheet 5 IN VE N TORS HANS A. JENSEN ATT'YS.

NOV. 18, 1969 JENSEN ET AL 3,478,488

PACKAGING MACHINE Filed March 27, 1967 6 Sheets-Sheet 6 nv VEN TORS v HANS A. JENSEN YRON J.M R ER BYM M HTT'YS.

United States Patent 3,478,488 PACKAGING MACHINE Hans A. Jensen and Myron J. Merdler, Madison, Wis., assignors to Oscar Mayer & Co., Inc., Chicago, Ill., a corporation of Illinois Filed Mar. 27, 1967, Ser. No. 626,297 Int. Cl. B65]: 31/02, 51/14 US. Cl. 53-112 15 Claims ABSTRACT OF THE DISCLOSURE An apparatus for vacuumizing and pressure sealing an assembly of package elements which is characterized by vertically aligned, relatively movable lower and upper vacuum chamber and sealing die members between which the package elements are clamped and associated mechanism for evacuating a plurality of compartments in the lower member when a series of connected product-receiving package forms are seated therein and the die members are closed, and for sealing portions of the package forms which are trapped between the dies while pressure is applied to opposite faces of the product enclosing portions so as to compress the product and fill the product accommodating space within the packages.

This invention relates to packaging and is concerned with improvements in an apparatus for vacuumizing and pressure sealing, while under vacuum and in a compressed state, a plurality of connected package assemblies of the type Which are characterized by a preformed, cup-shaped body of semi-rigid plastic which encompasses the product and a rigid or semi-rigid panel-like closure member forming the bottom of the package and supporting the product therein, with the body and closure members having telescoping portions and marginal flange portions which are superimposed and heat sealed.

A package which is especially designed for marketing sliced luncheon meat and similar products has been developed which comprises a preformed tray or cup-shaped, transparent plastic container body for encompassing a predetermined quantity of the product in snug relation and a closure member of rigid or semi-rigid plastic having a product supporting panel or raised platform like portion which telescopes within the container body and a flange surrounding the product supporting panel which is adapted to be sealed to an overlying flange on the margins of the container body with the package being vacuumized and heat sealed while pressure is applied on the top and bottom faces so as to compress the product and substantially fill the space within the package and provide a unitary package assembly. In producing this type package it has been found convenient to shape a plurality of the package elements in connected relation from plastic sheet materials, fill the container body forming elements with the desired amount of product, for example, one-half pound or a pound of sliced luncheon meat in each of the body forming cavities, assemble the cover forming elements therewith and subject the assembly to a vacuum while applying pressure to the opposite faces of the assembly and while heat and pressure sealing the flange forming portions surrounding each of the product filled cavities, thereby to produce a plurality of the packages in connected relation. The sealed assembly is thereafter trimmed or cut apart so as to provide the separate individual packages. The general object of the present invention is to provide an apparatus of a semi-automatic nature which will accept the aforesaid package assemblies and accomplish the closing and sealing operations while the assemblies are vacuumized and pressure is applied to the oppositely disposed top and bottom faces of each of the packages in the assemblies.

Patented Nov. 18, 1969 It is a more specific object of the invention to provide an apparatus for closing and sealing a plurality of connected package units which are initially formed by shaping sheet material so as to provide a series of connected productreceiving cavities in one sheet and a series of connected closure panels in another sheet having portions which telescope within the cavities wherein the apparatus comprises a compartment vacuum chamber or die member and a cooperating pressure die member mounted for relative movement toward and from each other in a vertical path with cam means for opening and closing the dies upon the package assembly and associated mechanism for applying vacuum to the package units before they are sealed and for heat sealing around the margins of each package unit while pressure is applied to the top and bottom faces thereof so as to compress the product and cause the same to conform to the interior of and to fill the space within each package unit.

It is a further object to provide an apparatus of the type described which is semi-automatic and requires only that the package assemblies be placed on a loading plate which is thereafter operative to deposit the assemblies in the proper relation between the closing and sealing dies and to return the same when closed and sealed to a position for ready removal from the machine.

These and other objects and advantages of the invention will be apparent from a consideration of the apparatus for closing and sealing multi-unit package assemblies which is shown by way of illustration in the accompanying drawings wherein:

FIGURE 1 is a side elevation of a machine which incorporates therein the principal features of the invention, with portions thereof being broken away;

FIGURE 2 is an elevation of the front or loading and discharge end of the machine, with portions thereof being broken away; 1

FIGURE 3 is a partial cross section taken on the line 3-3 of FIGURE 1, to a larger scale and with the dies being in the open position;

FIGURE 4 is a sectional view taken on the line 44 of FIGURE 1, to an enlarged scale;

FIGURE 5 is a partial section taken on the line 55 of FIGURE 1, to an enlarged scale; 7

FIGURE 6 is a fragmentary section taken on the line 6-6 of FIGURE 1, to an enlarged scale;

FIGURE 7 is a partial cross section taken on the line 77 of FIGURE 6, to a larger scale and with the dies in the closed position;

FIGURE 8 is a fragmentary section taken on the line 88 of FIGURE 2, to an enlarged scale;

FIGURE 9 is a cross section taken on the line 9-9 of FIGURE. 1, to an enlarged scale and with portions broken away;

FIGURE 10 is an exploded perspective view showing, in the inverted position in which they are placed in the machine, package elements which are adapted to be closed and sealed in the machine; and

FIGURE 11 is a perspective view showing a portion of the closed and sealed package assembly, the assembly being shown with the packages in the upright position.

Referring first to FIGURES 10 and 11 of the drawings, the package elements, which are adapted to be closed and sealed by the machine which is illustrated, comprises a sheet 10 of transparent plastic of a semirigid character which is preformed to provide a series of connected container bodies constituting product accommodating cavities 11 in each of which a quantity of a product 12 is adapted to be placed with the sheet 10 being inverted so that the cavities 11 are open side up, and a complementary closure sheet 13 formed with a series of depressed panels 14 which are spaced according to the spacing of the cavities 11 and are adapted to telescope within the open sides of the cavities 11 when the sheet 13 is placed on the sheet and pressure is applied to the opposite faces thereof. When the cavities 11 are filled with the desired amount of the product 12 and the sheet 13 is placed thereon the assembly is positioned in the machine for vacuumizing, compressing and sealing operations so as to produce the multi-unit package assembly shown in FIGURE 11.

The machine comprises an upright supporting frame having a horizontally disposed, generally rectangular main frame portion 20 (FIGURES 1 and 2) supported at the front end by pedestal forming side frame members 21 and at the rear end by depending legs 22. The side frame members 21 support at the front end of the machine a lower die or vacuum chamber assembly 24 and a vertically aligned upper die or pressure applying and heat sealing assembly 25. The upper die assembly 25 is in a fixed position while the lower die assembly 24 is mounted for vertical movement and controlled by a pair of cam plates 26 and 26' mounted for horizontal sliding movement on the main frame 20. A loading and discharge plate assembly 27 is mounted for movement in a path extending between the two

die assemblies

24 and 25 on a horizontal- 1y disposed frame 28 which is supported and guided on the main support frame 20 for horizontal reciprocation.

The lowermost vacuum chamber or die assembly 24 comprises an upwardly opening, tray-like member 30 (FIGURES 3 to 7) in which there are mounted a series of inserts 31 each forming an upwardly opening, pack age receiving compartment or cavity 32 which is of a size to receive the container body or cavity forming portions 11 of the preformed sheet 10. In the form illustrated the container bodies are of cylindrical shape. Each insert 31 is provided on its uppermost face with a gasket 33 of resilient seal forming material surrounding the edge of the compartment 32. A pressure applying plate 34 is mounted for movement in each compartment 32 on a stem 35 which is slidable in a sleeve 36 seated in an air sealed bore 37 which extends through the bottom of the die member 30 in the center of each compartment 32. The stem 35 also extends through a bore in a supporting cross plate 38 on which the member 30 is mounted and into a socket forming bore 40 in a member 41 upstanding from a fixed cross plate or bar 42. A compression spring 43 is seated in the bore 40 and urges the stem 35 in an upward direction. A larger compression spring 44 is seated at its lower end on a shoulder 45 of member 41 and at its upper end on a shouldered washer 46 beneath the plate 38. The spring 44 exerts a downward force on the stem 35 and operates to restrain the stem 35 and plate 34 against following the entire die assembly 24 in the upward movement thereof. The movement of the stem 35 relative to member 41 is limited by a pin 47 operating in a slot 47' in the wall of member 41. The cross bars 42 (FIGURES 1-3 and 7) are slotted at 48 beneath each member 41 so as to permit the members 41 to be lifted above the bars 42 by stop forming brackets 49 mounted on the depending plate 50 of the die assembly 24. As the stops 49 move upwardly with the assembly 24 they pass through slots 48 in the bars 42 and lift the members 41 off of bars 42. The contact of stops 49 with the members 41 determines the full travel of the stems 35 and the plates 34. The position of the stems 35 and plates 34 relative to the cavities 32 is not affected by any further upward movement of the stops 49.

The plate 38 on which the die assembly 24 is carried forms the top of a T-shaped member having a depending flange or web 50, Track forming

members

51 and 51 are mounted at opposite ends of the depending web 50 which provide vertically extending

lower guideways

52 and 52 for receiving guide rollers 53 and 53' which are journaled in end portions of side frame members 54 and 54', the latter being connected to the inside faces of the frame members 21. Wear plates 55 and 55' are mounted on the guide rollers 53 and 53' against which the outermost vertical edges of track members 51 and 51' bear so as to hold the assembly in a vertical path with substantially no endwise movement. Triangular-shaped end plates 56 and 56' are upstanding on the ends of the cross plate 38 and carry guide rollers 57 and 57' at the apex forming tops thereof which are received in vertical guideways 58' and 58' provided by track forming members 60 and 60' mounted on the frame members 21. The guideways 58 and 58' are in vertical alignment with the guideways 52 and 52' so as to insure proper vertical movement of the assembly 24.

The end plates 56 and 56' carry at the center of their base portion cam rollers 61 and 61 (FIGURES 1-3) which are operative in

cam tracks

62 and 62 in the oppositely disposed faces of vertically disposed cam plates 26 and 26'. The cam plates 26 and 26' extend upwardly of elongate slide members 64 and 64' which are mounted for horizontal reciprocation in pairs of

track formations

66, 67 and 66', 67' which are spaced longitudinally of the horizontal frame 20 and supported on the top faces of side frame members 54 and 54'. Each track formation has an upwardly opening, track forming recess 68 (FIGURE 3) which slidingly receives the slide member 64 or 64' and retaining gibs 70 and 70' which are received in longitudinally extending slots 71 and 71' in the side faces of the slide members 64 and 64'. The slide members 64 and 64' are reciprocated by operation of the hydraulic cylinder 75 (FIGURE 1) which is mounted on a cross frame channel member 76 at the rear end of the frame 20. The cylinder 75 extends toward the front of the machine with the piston 77 connected by clevis 78 and pin 79 (FIG- URES l and 4) to a cross plate member 80 connecting the

slide members

64 and 64. Spring backed bumpers 81 are mounted on angle brackets 82 on the side frame members 54 and 54' to act as a cushion stop for the

slide members

64 and 64. A cam plate 83 is suspended at its forward end from the clevis 78 by a depending bracket 84 and rides in a guide bracket 85 on the bottom of cylinder 75 for operating a valve assembly 86 which is mounted at the inner end of the cylinder 75 and which controls the flow of fluid to the cylinder 75 and thus varies the movement of piston 77. The piston movement is varied so that the package assembly is placed in the cavities more gently. A more gradual accelerated start of travel is obtained and a more gradual deaccelerated end of travel.

The upper die or chamber assembly 25 (FIGURES 3, 6, 7 and 8) comprises a downwardly opening, traylike base member 90 which is secured on the bottom face of the lawer flange 91 of a cross I beam 92 forming the top frame member at the front of the machine and being connected at opposite ends to the vertical frame members 21. The downwardly facing recess 93 in the base member 90 houses a diaphragm 94, a piston and guide plate assembly and a heat and pressure platen 96. The diaphragm 94 is in the bottom of the recess 93 and is clamped therein by the guide plate 95 which is secured to the base member 90 by bolts 97. The guide plate 95 is recessed at 98 to slidingly receive, for limited downward movement, a series of piston members 99. The pistons 99 are mounted as shown in FIGURE 3 with interengaging shoulders 100 permitting a limited movement in the guide recesses 98. The lower faces of the piston members 99 bear against the upper face of the platen 96. The platen 96 is suspended from the guide plate 95 by a plurality of shouldered screws 101 which have their shank ends threaded into suitable bores in the guide plate 95 and extend downward through bores 102 in the platen 96 with the head portions movable in bottom portions of the bores which are of larger diameter and in which a compression spring 103-is trapped so as to normally hold the platen 96 in retracted or elevated position as shown in FIGURE 3. Pads 104 are mounted on the lower face of the platen 96 which are in alignment with the recesses 32 in the lower die assembly 24. The platen 96 is provided with a series of tubular passageways 105 which are connected at one end of the platen to the lower ends of vertically disposed conduits 106 and 106 (FIGURE 8), each of which extends upwardly through a spring pressed seal assembly indicated at 107 so as to permit the

conduits

106 and 106 to move vertically with the movement of the platens 96. The conduits 106 and 106' extend through apertures in the bottom flange 91 of the I beam 92 and carry collars 108 and compression springs 109. The

conduits

106 and 106 are connected with a suitable steam supply which is circulated through the platen 96 to heat the same. An opening 111 (FIGURE 7) in the side wall of the base member 90 is connected by suitable conduit to a vacuum line indicated at 112 and controlled by

valves

113 and 114. Passageways indicated at 115 and 116 in member 90 (FIGURES 3, 6 and 7) are connected by means of suitable conduits 117 and control valve 118 to an air pressure line and an exhaust line so that pressure may be applied through the diaphragm 94 to the pistons 99 to force the heated platen 96 downwardly against the action of the springs 103 and into pressure applying engagement with the package closure panels when the lower die assembly 24 is raised into engagement with the upper die assembly 25 and vacuum has been applied to the interior of the dies to exhaust the air from the package units.

The loading and unloading apparatus 27 which is provided for positioning the package assembly between the upper and lower die

members

25 and 24 so that the package body forming elements 11 are seated in the recesses 32 in the lower die assembly 24 and for removing the sealed assembly after the sealing operation and separation of the

die assemblies

24 and 25 is shown in FIG- URES 1, 2, 4 and 7. The apparatus 27 comprises a horizontally disposed loading plate 120 with recesses 121 cut in the forward margin to accommodate the container body elements 11 when the package assembly is placed thereon. The fork-like loading plate 120 is secured at its rearward margins to longitudinally extending, parallel bars 122 constituting part of a horizontally disposed top frame 125. The frame 125 includes parallel, transversely extending rod or bar members 126 and 127 which are rotatably mounted in bushings 128 spaced axially of the cross bars 126 and 127 and mounted in the longitudinal bars 122. The cross bars 126 and 127 are pivotally connected at their ends with the cross bars 130 and 131 of a lower frame 136 by means of short parallel link bars 137. The bottom frame 136 is mounted for horizontal sliding movement between vertically extending, parallel side plates 138 and 138' (FIGURE 9) which are upstanding from the side frame bars 54 and 54'. The cross bars 130 and 131 are connected at their opposite ends to side rail members 140 and 140' which carry on their upper faces longitudinally extending gib plates 141 and 141', the outer margins of which overhang the outer face of the

bars

140 and 140 and are received in sliding relation in longitudinal guideway 142 and 142' formed between longitudinally extending

bars

143, 144 and 143',

144 which are secured on the oppositely disposed inside faces of the

vertical frame plates

138 and 138. Longitudinal guide rails 145 and 145 are spaced above the guide rails 144 and 144' so as to form a cam track 146 and 146' for receiving

cam rollers

147 and 147 on the extended ends of the front cross bar 126 of the top frame 125. Each of the cam tracks 146 and 146' has a forward portion 148, 148' which is elevated so as to raise the loading plate 120 as it is moved forwardly to extend the same for receiving the package assembly and to lower the plate 120 as it is moved rearwardly of the machine to deposit the package assembly on the loWer die assembly 24. The side rails 140 and 140' are provided with rack teeth 150 and 150' on their bottom faces which engage with gears 151 and 151' mounted on a cross shaft 152 which is journaled in bearings 153 and 153' supported on the vertical plates 138 and 138'. The shaft 152 extends through the plates 138 and 138' and carries

pinions

154 and 154 which engage with racks 155 and 155' mounted on the tops of the slide members 64 and 64' which carry the camplates for raising and lowering the lower die assembly 24.

The operation of the apparatus is controlled by suit able electric circuitry which includes solenoid controlled electronic timers and solenoid operated air valves. Two starting

switches

160 and 161 are arranged at the front of the machine and connected into the control circuit so that these two switches must both be held simultaneously by the operator until the lower die assembly 24 is raised into closed relation with the upper die assembly 25. The switches are spaced so that both hands are required for operation so as to safeguard the operator. Closing of the two

switches

160 and 161 operates solenoid air valve indicated at 162 which connects the air supply line to the hydraulic cylinder 75 and moves the cam plates 26 and 26' forwardly so as to raise the lower die assembly 24. The movement of the slide members 64 and 64' which carry the cam plates 26 and 26' actuates the loading assembly 27 through the rack and pinion connection and the cross shaft 152. The loading plate 120 moves back and down so as to deposit the package assembly on the lower die assembly 24 as the latter moves upwardly. Switch 163 which is mounted on the side plate 138 is operated by cam plate 164 on the slide member 64 as the latter is moved forward to close the lower die assembly 24 on the upper die assembly 25. The switch 163 controls the operation of a variable electronic timer which operates and times solenoid

valves

113 and 114 controlling the vacuum line 112 for evacuating the interior of the

die assemblies

24 and 25 after they are closed on each other and sealed. The valve 113 is opened and 114 is closed and timed by the variable electronic timer and at the same instant the timer for controlling the vacuum line is started, a second variable electronic timer is also started, the only function of which is to time the delay of starting a third variable electronic timer, with the time interval corresponding to the time the interior of the unsealed packages are exposed to vacuum. The third timer starts and times the cycle of the steam heated pressure platen 96 by opening the solenoid operated air valve 118 (FIGURE 6) which allows compressed air to enter the top die 25 through passageways and 116 so as to apply pressure to the diaphragm 94. The force of the compressed air is transmitted by the three pistons 99 to the steam heated pressure platen 96 and the latter moves down onto the package components. As the pressure is applied, the heat activates an adhesive which seals the packages. Upon completion of the time of the vacuum timer, the vacuum is shut off and the area is opened to atmosphere. Upon completion of the time of the pressure timer, the area above the diaphragm 94 is changed from pressure to vacuum which helps return the platen and also prevents prematurely lowering platen 96. The completion of the time of the pressure timer also starts the reverse motion of the hydraulic piston 75 which lowers the die assembly 24 and simultaneously moves the loading plate forward and upward so as to remove the sheet of sealed packages and return the same to loading position. This completes the cycle of operation of the machine.

In operating the machine a package assembly is placed on the fork-like loading plate 120 and the two starting switches and 161 are held closed while the loading plate 120 moves back and down to deposit the package assembly in the lower die assembly with the container body members positioned in the cavities 32 and depressing the pressure plates 34 against the force of the springs 43. The lower die assembly 24 is simultaneously moved upwardly by cam plates 26 and 26' and closes on the upper die assembly 25 as the loading plate moves back out of the way. The vacuum line 112 is opened by operation of

valves

113 and 114 so as to exhaust the air in the chamber formed by the closed dies. After a predetermined time interval the valve 118 is opened and air pressure is applied to the diaphragm 94 which lowers the heated pressure platen 96 to compress the packages and heat seal the superimposed flanges of the container body and closure members. The

valves

113 and 114 are operated to relieve the vacuum and the die assemblies are separated by backward movement of the

cam plates

26 and 26. The loading plate 120 moves forward and up to strip the sealed package assembly from the lower die assembly and returns the same to loading position for removal from the machine.

While particular materials and specific details of construction are referred to in describing the form of the machine illustrated, it will be understood that other materials and equivalent structural details may be resorted to Within the spirit of the invention.

We claim:

1. A machine for closing and sealing a package assembly which is characterized by a preformed semirigid tray-like container body having a peripheral flange portion extending outwardly of the bottom of the body and a semi-rigid closure panel with a raised product supporting platform adapted to be telescoped within the bottom of the container body and a peripheral flange adapted to be sealed in face engagement with the overlying flange portion of the container body, said machine comprising an upright supporting frame, a lower die assembly mounted for vertical movement on said frame and having an upwardly opening recess in which a container body is adapted to be positioned in inverted relation with a quantity of a product in said body and with a closure panel, also in inverted relation, positioned thereon, an upper die assembly supported on said frame and aligned vertically with said lower die assembly, means for raising said lower die assembly into sealing engagement with said upper die assembly, means for connecting a vacuum line to said die assemblies so as to withdraw air from the die assemblies and the package elements enclosed between the die assemblies, said upper die assembly having a movable pressure applying platen therein with marginal portions thereof overlying marginal portions of the lower die assembly around said upwardly opening recess and means to connect said upper die assembly to an air pressure supply line so as to apply sufficient pressure to said platen to move the same into pressure applying engagement with said closure panel thereby to compress the product between the top of the container body and the platform portion of the closure panel so that the product fills the space within the package while applying sealing pressure to the flange of the container body and the underlying flange of the closure panel trapped between the marginal portions of said lower die assembly and said pressure applying platen.

2. A machine as recited in claim 1, and said lower.

die assembly having a pressure applying plate movably mounted therein for co-operation with said platen to compress the product and the associated container body and closure panel portions.

3. A machine as recited in claim 2, and said pressure applying plate having a resilient supporting means.

4. A machine as recited in claim 2, and said pressure applying plate having a depending stem and spring means operatively connected to said stem and said die assembly so as to resiliently urge said plate into pressure applying engagement with the lowermost face of the container body.

5. A machine as recited in claim 1, and said upper die assembly having a guide member and piston means engaging said platen for moving the platen into engagement with the closure panel of the package assembly.

6. A machine as recited in claim 1, and said pressure applying platen being mounted in said upper die assembly on depending supports having resilient means for resisting downward movement of said platen.

7. A machine for closing and sealing a package assembly which is characterized by a preformed semi-rigid tray-like container body having a peripheral flange portion extending outwardly of the bottom of the body and a semi-rigid closure panel with a raised product supporting platform adapted to be telescoped within the bottom of the container body and a peripheral flange adapted to be sealed in face engagement with the overlying flange portion of the container body, said machine comprising an upright supporting frame, a lower die assembly mounted for vertical movement on said frame and having an upwardly opening recess in which a container body is adapted to be positioned in inverted relation with a quantity of a product in said body and with a closure panel, also in inverted relation, positioned thereon, an upper die assembly supported on said frame and aligned vertically with said lower die assembly, means for raising said lower die assembly into sealing engagement with said upper die assembly, means for connecting said die assemblies to a vacuum line so as to withdraw air from the package elements enclosed between the die assemblies, said upper die assembly having a movable pressure applying platen therein and means to connect said upper die assembly to an air pressure supply line so as to move said platen into pressure applying engagement with said closure panel thereby to compress the product between the top of the container body and the platform portion of the closure panel so that the product fills the space within the package while sealing the flange of the container body to the flange of the closure Panel, and a diaphragm in said upper die assembly which is interposed between said platen and the connection with the air pressure supply line so as to equalize the pressure exerted on said platen.

8. A machine as recited in claim 1, and means incorporated in said platen for heating said platen so as to heat seal the face engaging flanges on the body portion and the closure panel of the package assembly.

9. A machine for closing and sealing a package assembly which is characterized by a semi-rigid sheet material which is preformed to provide one or more traylike container bodies each having a peripheral flange portion extending about an open side which constitutes the bottom thereof and a semi-rigid sheet of similar material which is preformed to provide a corresponding number of bottom closure panels each having a raised product supporting portion adapted to be telescoped within the open side of a container body and a peripheral flange portion adapted to be sealed in face engagement with the flange portions of the associated container body, said machine comprising a supporting frame, a lower die assembly mounted on said frame and having an upwardly opening recess in which a container body is adapted to be positioned in inverted relation with a quantity of a product in said body and with a closure panel portion assembled in inverted relation thereon, an upper die assembly supported on said frame and aligned vertically with said lower die assembly, means for moving said die assemblies into closed position with said package assembly enclosed between the same and for separating said die assemblies to free the package assembly, means for connecting said die assemblies to a vacuum line so as to withdraw air from the package assembly, said die assemblies having means to apply pressure to the uppermost and lowermost faces of the package assembly enclosed therein whereby to compress the product so that it fills the space within the package and means for sealing the package flanges which are in face engagement with each other, and means associated with said die assemblies for supporting a package assembly while moving it into position for deposit in the lower die assembly as said die assemblies are closed upon each other and for removing the sealed package assembly from said lower die assembly as said die assemblies are separated.

10. A machine as recited in claim 9, and said means for supporting and moving said package assembly comprising a fork-like supporting plate, a carriage forming frame mounted for reciprocable movement on said supporting frame.

11. A machine for closing and sealing a package assembly which is characterized by a semi-rigid sheet material which is preformed to provide one or more traylike container bodies each having a peripheral flange portion extending about an open side which constitutes the bottom thereof and a semi-rigid sheet of similar material which is preformed to provide a corresponding number of bottom closure panels each having a raised product supporting portion adapted to be telescoped within the open side of a container body and a peripheral flange portion adapted to be sealed in face engagement with the flange portions of the associated container body, said machine comprising a supporting frame, a lower die assembly mounted on said frame and having an upwardly opening recess in which a container body is adapted to be positioned in inverted relation with a quantity of a product in said body and with a closure panel portion assembled in inverted relation thereon, an upper die assembly supported on said frame and aligned vertically with said lower die assembly, means for moving said die assemblies into closed position with said package assembly enclosed between the same and for separating said die assemblies to free the package assembly, means for connecting said die assemblies to a vacuum line so as to withdraw air from the package assembly, said die assemblies having means to apply pressure to the uppermost and lowermost faces of the package assembly enclosed therein whereby to compress the product so that it fills the space within the package and means for sealing the package flanges which are in face engagement with each other and said means for moving said die assemblies comprising a traveling carriage and co-operating cam means on said carriage and on one of said die assemblies.

12. A machine as recited in claim 11, and means associated with said die assemblies for moving a package assembly into position for deposit in the lower die assemby and for removal of the sealed package assembly therefrom, which means is operated by means responsive to movement of said traveling carriage.

13. A machine for closing and sealing a package assembly which is characterized by a semi-rigid sheet material which is preformed to provide one or more tray-like container bodies each having a marginal flange portion extending about an open side which constitutes the bottom thereof and a semi-rigid sheet of similar material which is preformed to provide a corresponding number of bottom closure panels each having a product supporting portion adapted to close the open side of a container body and a marginal flange portion adapted to be sealed in face engagement with the flange portions of the associated container body, said machine comprising a supporting frame, a lower die assembly mounted on said frame and having an upwardly opening recess in which a container body is adapted to be positioned in inverted relation with a quantity of a product in said body and with a closure panel assembled in inverted relation thereon, an upper die assembly supported on said frame and aligned vertically with said lower die assembly means for moving said die assemblies into closed position with said package assembly enclosed between the same and for separating said die assemblies to free the package assembly, said die assemblies having means to apply pressure to the uppermost and lowermost faces of the package assembly enclosed therein whereby to compress the product so that it fills the space within the package and means for sealing the package flanges which are in face engagement with each other, and said means for moving said die assemblies into closed position comprising a carriage forming frame mounted on said supporting frame for horizontal reciprocation, cam plates on said carriage and cam followers on one of said die assemblies for co-operation with said cam plates so as to move said die assemblies into and out of closed position upon reciprocation of said carriage.

14. A machine for closing and sealing a package assembly which is characterized by a semi-rigid sheet material which is preformed to provide one or more traylike container bodies each having a marginal flange portion extending about an open side which constitutes the bottom thereof and a semi-rigid sheet of similar material which is preformed to provide a corresponding number of bottom closure panels each having a product supporting portion adapted to close the open side of a container body and a marginal flange portion adapted to be sealed in face engagement with the flange portions of the associated container body, said machine comprising a supporting frame, a lower die assembly mounted on said frame and having an upwardly opening recess in which a container body is adapted to be positioned in inverted relation with a quantity of a product in said body and with a closure panel assembled in inverted relation thereon, an upper die assembly supported on said frame and aligned vertically with said lower die assembly, means for moving said die assemblies into closed position with said package assembly enclosed between the same and for separating said die assemblies to free the package assembly, said die assemblies having means to apply pressure to the uppermost and lowermost faces of the package assembly enclosed therein whereby to compress the product so that it fills the space within the package and means for sealing the package flanges which are in face engagement with each other, and a fork-like means mounted on said. supporting frame for horizontal reciprocation which is adapted to receive a package assembly and deposit the same on the lower one of said die assemblies so that it is enclosed between said die assemblies when the latter are in a closed position.

15. A machine as recited in claim 14, and said forklike means being operated to remove a completed package assembly form said lower die assembly when the die assemblies are moved to open position.

References Cited UNITED STATES PATENTS 2,918,767 12/ 1959 Grinstead et al. 531l2 3,020,686 2/1962 Reuckert et al. 531l2 X 3,196,590 7/1965 Ollier et al. 53-112 TRAVIS S. McGEHEE, Primary Examiner U.S. C1. X.R. 53-101