US2823729A

US2823729A - Cooling means for package seals

Info

Publication number: US2823729A
Application number: US501403A
Authority: US
Inventors: Merlin A Stickelber
Original assignee: Stickelber and Sons Inc
Current assignee: Stickelber and Sons Inc
Priority date: 1955-04-14
Filing date: 1955-04-14
Publication date: 1958-02-18
Anticipated expiration: 1975-02-18

Description

Feb. 18, 1958 M. A. sTlcKx-:LBER

COOLING MEANS FOR PACKAGE SEALS 2 Sheets-Sheet 1 Filed April 14, 1955 ma mk VC mw 5 A. m M w.

WP. F22@ A from/Ey Feb- 18, 1958 M. A. STICKELBER 2,823,729

COOLING MEANsUFoR PACKAGE SEALs iled April 14, 3955 2 sheets-sheet a MERLIN A. STICKELBE/c? A T TO/PVEV United States Patent O COLING MEANS FOR PACKAGE SEALS lMerlin A. Stickelher, Kansas City, Mo., assignor to Stickelber & Sons, Inc., a corporation of Missouri.

Application April 14, 1955, Serial No. 501,403

Claims. (Cl. 154-42) My invention relates to cooling means for package seals, and more particularly to cooling means for the seals of wrapped packages, such as wrapped bread, or similar products, that are sealed in a wrapper that is heated for sealing purposes, such as the `ordinary wax paper used for bread. The present invention is an improvement over that disclosed in my application Serial No. 358,463, tiled May 29, 1953, on Cooling Means for Package Seals, patented June 14, 1955, Patent No. 2,710,641.

As the room temperature in bakeries often exceeds that at which paraflin wax, or similar wax, used for bread wrappers will congeal, it has been found necessary to cool the seals of the packages. ln wrapping the bread the wrapper is folded over on itself in such a way as to enclose the loaf completely in the wrapper and heat is applied to the folded wax paper wrapper so as to cause the wax coating thereon to be softened and substantially liqueed, so that upon cooling it will congeal and secure the folded and overlapped plies of paper of the wrapper together so as to seal the package. ln order to obtain a good seal and to assure that the packages will not become unwrapped after supposedly having become sealed, by Contact with the surrounding atmosphere, which, prior to cooling the Seals, was depended upon for congealing the wax coating on the paper, it has been found necessary to cool the seals of the packages materially in order that such congealing of the waX will take place. Not only is such cooling necessary and desirable for wax paper wrapped sealed packages, but also for packages that are sealed in other wrappers, such as cellophane, which requires heat for bringing the material to such a temperature that the layers thereof can be sealed together.

In order to accomplish the cooling of the seals, cooling units or plates have been provided with which the seals of the packages move into sliding contact, and it has been found that due to the fact that the wax of the wrapper has a tendency to adhere to the metal surfaces of the cooling units or plates, it has been found necessary, in order to accomplish successful cooling of the seals without disarranging the wrappers of the packages and possibly causing the same to become opened by sticking to the cooling plates while being moved relative to the same, that a coating of frost or ice has t-o be created on the cooling units or plates so that this sticking will not occur. This necessitates the use of direct expansion refrigeration in the cooling plates or units, which requires considerable equipment, as the temperature of the seal contacting surfaces of said units has t0 be kept considerably below the freezing point of water in order to maintain the ice or frost on the surfaces thereof that engage the seals.

It is the principal purpose of my invention to provide cooling means for package seals that does not require the forming of a coating of frost or ice on the cooling means, as my improved cooling means is of such a character that will not adhere thereto at any temperature, and accordingly it is unnecessary to maintain a coating of ice or frost thereon. While direct expansion refrigeration can be used for cooling the cooling units or plates, it is not absolutely necessary in accordance with the present invention, and where used the direct expansion refrigeration means is so adjusted that it does not cool the seal engaging surface of the cooling unit to such a temperature that ice or frost is formed thereon. While it is desirable to cool the seals to a temperature considerably below the room temperatures that are ordinarily encountered in bakeries, and particularly in bakeries during the hot summer months, with my improved cooling means it is unnecessary to use any refrigeration in connection with the cooling of said cooling units or plates. The temperature that may be desired to accomplish the purpose of congealing the wax of the seals need only be below the temperature at which the wax will congeal. If the cooling units are made of suicient size that the seals will be in engagement therewith for a considerable period of time in their passage through the cooling apparatus, the temperature of ordinary tap water is sufficient for accomplishing the congealing of the wax so as to obtain a perfect seal of the packages before leaving the cooling means, but if a shorter period of contact with the cooling units is desired, these can be made of less length and a temperature of the cooling :iedium maintained that is considerably below the tempetature of ordinary tap water, as long as it is above the freezing point yof water, and either direct expansion refrigeration or brine can be used as a cooling medium.

More specifically my invention comprises cooling means for seals of wrapped packages having a wall that the seals thereof engage, that is made of metal but which has a covering layer or ply on the face thereof with which the seals engage that is of a synthetic resin that has an inherent greasiness and a negligible adhesive factor with respect to wax, The covering material of such synthetic resin can be either applied thereto in a thin ply or sheet by being cemented or sealed to the metal face to face, or can be provided on the metal wall by means of a coating that is sprayed on the face of the metal and baked thereon so as to firmly adhere thereto. Certain synthetic resins have the characteristic that, while they are substantially inert and do not transfer any of their greasy characteristics to the material coming in Contact therewith, they have a greasy feel to the surface thereof and are inadhesive to wax and many other materials. The specific materials that have these characteristics particularly are polytetraiiuoroethylene, polyethylene and tritluorochloroethylene polymer. None of these materials are adversely affected by being cooled to the temperatures that are desirable in a device for cooling seals of wrapped packages and can be subjected to the temperatures now utilized in devices of this character that utilize direct expansion refrigeration without any harmful effects upon the materials. Also all of these materials are substantially inert within the ternperature range to which the same would be subjected in use in such a cooling apparatus and are suiciently good conductors Vof heat to be used for the purpose of cooling package seals when applied in a relatively thin layer to a metallic heat conducting wall.

"My invention is appli-cable not only to a continuous flat faced wall that has a flat face that is provided with the coating or covering ply with which the seals of the es packages slidably engage, but is also applicable to a cooling element that is made up of tubular members that are rectangular in cross section and that collectively form a wall, the corresponding side faces of the tubular members forming said wall forming the face of the unit that is contacted by the package seals and being provided in the present invention with a covering or coating of the synthetic resin of the above referred to character to prevent the adherence of the wrappers thereto.

Other objects and advantages of my invention will appear as the description of the drawings proceeds. l desire to have it understood, however, that l do not intend to limit myself to the particular details shown or described, except as defined in the claims.

In the drawings:

Fig. l is a fragmentary top plan View of a sealing apparatus, partly broken away, to which my improved cooling means for seals is applied.

Fig. 2 is a vertical longitudinal sectional view thereof partly broken away.

Fig. 3 is a section on an enlarged scale, taken on the line 3 3 of Fig. 1.

Fig. 4 is a fragmentary section corresponding to Fig. 3 but on a still larger scale.

Fig. 5 is a view similar to Fig. 3 of a modification, and

Fig. 6 is a fragmentary sectional View similar to Fig. 4, of the form of the invention shown in Fig. 5.

Referring in detail to the drawings, my improved cooling means is shown as comprising a pair of cooling units 10 that engage the end seals of wrapped packages, such as loaves of wrapped bread, and a cooling unit 11 that engages the bottom seals of said packages. The units 10 are mounted for adjustment toward and away from each other so that the cooling apparatus can be adjusted for acting on the end seals of packages, such as Wrapped loaves of bread, of various lengths. Such adjustable mounting may be of any desired character, but preferably consists of pairs of

brackets

12 and 13 that are mounted on transversely extending

shafts

14 and 15, which shafts are provided with screw-threaded portions 16 that are of opposite pitch, as is common in devices of this character, so that rotation of the shafts 14 and in one direction will move the brackets 12 and the brackets 13 toward each other while rotation of said shafts in the opposite direction will move said

brackets

12 and 13 away from each other. Said

shafts

14 and 15 are each mounted for rotation in a pair of brackets on a pair of longitudinally extending frame bars 17, means being provided to hold the shafts against endwise movement in said brackets.

Said bars 17 are mounted in any suitable manner on a suitable support and may be mounted on the frame (not shown) of a wrapping machine and of the convey ing apparatus usually associated with such a machine, if desired. Mounted on said bars 17 are the brackets 18, which support the table or plate-like member 19 over which the upper run of the conveyor belt 20 extends, said conveyor belt being mounted on a pair of rollers 21, which are mounted in any suitable manner on the cooling apparatus, as on the brackets 17 mounted on the members 17, and are driven in any suitable manner so as to move the upper run of the belt 20 in the direction indicated by the arrow in Fig. 2, the particular mounting and drive of said conveying means not being part of this invention, it being only of importance that means be provided for moving the wrapped packages, the seals of which are to be cooled, along the cooling units 10 in sliding engagement therewith.

The

brackets

12 and 13 are connected together by means, of a pair of longitudinally extending bars 22 and thecooling units Il@ are mounted on said bars 22. The shaft 14 is provided with a hand wheel 23 that has a handle 24 thereon for rotating said shaft and the rotation of said shaft simultaneously rotates the shaft 15 through the

sprockets

25 and 26 keyed on said shafts 14 4 and 15 and the sprocket chain 27 so that both pairs of

brackets

12 and 13 are adjusted toward or away from each other simultaneously and equally.

ireferably, the conveying means in the form of a belt is also provided for engagement with the upper sides et the wrapped packages, being mounted on rollers 29 that are mounted for rotation in any suitable manner on the longitudinal frame members 3), and one of said rollers 29 is driven in any suitable manner. Preferably the driven rollers 2l and 29 for the conveyor belts 2t) and 28 are driven in any suitable manner from some rotating part of the wrapping machine with which the cooling device is associated. The conveyor belt 28 is adjustable by adjustment of the frame members 30 relative to a pair of longitudinally extending bars 31 that are mounted in any suitable manner, as on the frame of the wrapping machine and the frame of a conveyor usually provided for conveying the wrapped packages away from the cooling means.

Mounted on said longitudinally extending members 31 are a pair of transversely extending brackets 32 that have screw-threadedly engaged therewith the adjusting screws 33, said adjusting screws having means thereon for adjusting the same equally simultaneously, comprising a pair of sprockets 34 and the sprocket chain 35 operating over said sprockets. The lower ends of said adjusting screws are provided with heads thereon that engage the under sides of brackets 36 and are rotatably mounted in openings in said brackets, said brackets 36 supporting the longitudinally extending members 30. Thus the entire upper conveying means comprising the belt 2S, the rollers 29 and the longitudinally extending members 30, are adjustable vertically by means of said adjusting screws 33.

A fragmentary portion of the wrapping machine is shown in Figs. 1 and 2, showing the heating devices for the wrappers of the packages, these being shown somewhat diagrammatically in said figures as comprising the heating units 39 for the end seals of the packages and the heating unit 40 for the bottom seals. Any suitable means for conveying the wrapped loaves of bread into engagement with the heating means may be provided. Suitable flexible guide members 41 are provided between the heating units 39 and the cooling units 10. No means is provided for conveying the wrapped packages into engagement with the cooling unit 11 other than the conveying means 20 and 2S, as this is unnecessary, the packages that are being moved along by the

conveying means

20 and 28 in the direction of the arrow indicated in Figs. 1 and 2 pushing the packages ahead of them across the bottom sealing unit 11.

The sealing units 10 illustrated more in detail in Figs. 3 and 4 have flat faced walls 42 of metal and rear walls 43 and top and

bottom walls

44 and 45 that are provided with flanges 46 for securing the flat front plate 42 thereto by means of securing elements 47. It is, of course, to be understood that the end walls of the cooling units 10 are similarly flanged and similarly secured to the front plate 42, suitable compressible gasket means 48 being provided between the flanges 46 and the plate-like member 42. The rear wall 43 is preferably provided with a thickened portion 49 receiving screws 50 by means of which the cooling unit is secured to the bar 22.

ln the form of the invention shown in Figs. 3 and 4 the cooling Coil 51 is mounted within the housing formed by means of the metallic walls above described,

exible conduits

52 and 53 extending from the opposite ends of the cooling coil 51 to circulate cooling medium, such as brine, or an expandable cooling medium, through said cooling element 51. The housing is filled preferably with a jellylike viscous heat transfer medium 54, which remains in a mobile state at the temperatures to which it is subjected, or with a suitable anti-freeze solution serving as heat transfer means between the wall 42 and the cooling coil 51 and maintaining a close contact with the wall 42 to cool it uniformly over its entire surface.

The outer face of the wall 42 is provided with a synthetic resin covering material 55. Said covering material may be applied to the outer face of the metallic wall 42 by spraying and baking a coating of the synthetic resin material on said outer face of the metallic wall 42, or a thin sheet or ply of the synthetic resin material 55 may be bonded or cemented to the outer face of the wall 42 by means of cement suitable for bonding the synthetic resin material to the metal wall. The synthetic resin materials that are suitable for use for the covering material 5S on the outer face of the metallic wall 42 are polytetrauoroethylene, polyethylene and triuorochloroethylene polymer, having the formula (CF2CFCl) each of which has the property that wax will not stick or adhere thereto.

The cooling element 11 is made in the same manner as the cooling elements having the cooling coil 51 provided therein with the lengths thereof running transversely of the machine, or lengthwise of the cooling element 11, corresponding parts of the cooling element 11 and of the cooling element 10 shown in Figs. 3 and 4 having the same reference numerals applied thereto. The top wall 42 of the cooling element 11 corresponds to the wall 42 of the cooling elements 10 and is provided with a coating or covering ply of the synthetic resin material 55 in a similar manner as are the cooling elements 10.

Instead of making the cooling elements 10 and 11 with cooling coils separate from the package seal engaging wall, the cooling elements can be made as shown in the patent to Stoneman, Jr., 2,053,540, September 8, 1936, for Heat Exchange Unit for Wrapping Machines. In this form of the invention the rectangular conduits 56 are secured together in the relationship shown in Fig. 5 so that the rectangular tubular members 56 collectively form a wall that has passages 57 therein for the cooling medium, the wall portions 58 of said conduits 56 being in alignment with each other and collectively forming a flat seal engaging wall for the cooling unit. The cooling units 10 and 11 can each be made in this manner and are provided with heat insulating material 59 on the rear side thereof enclosed within a suitable housing, portions 60 only of which are shown in Fig. 5 of the drawings. The seal engaging metallic wall portions 58 are provided with a covering 55 of the synthetic resin in the'sarne manner as above described, the same synthetic resins being suitable for this covering or coating ply SS. While the covering or coating ply 55 is shown as being continuous over the wall made up of the wall portions S8, and this is preferred, the rectangular tubing sections 56 can have the coating or covering ply 55 applied to the wall portion 58 thereof individually, should this be found desirable, the important thing being that all of the surfaces of the cooling units that are in a position to be contacted by the packages that are to be sealed are covered by one of the synthetic resin materials above set forth.

What I claim is:

l. Cooling means for seals of wrapped packages comprising a metallic wall having a wax repellent synthetic resin surface covering on the outer face thereof, said surface covering being thin relative to the thickness of said wall, means for moving seals of wrapped packages into sliding engagement with said surface covering, and means for cooling said Wall.

2. Cooling means for seals of wrapped packages comprising a metallic wall having a polytetrauoroethylene surface covering on the outer face thereof, said surface covering being thin relative to the thickness of said Wall, means for moving seals of wrapped packages into sliding engagement with said surface covering, and means for cooling said wall.

3. Cooling means for seals of wrapped packages comprising a metallic wall having a polyethylene surface covering on the outer face thereof, means for moving seals of wrapped packages into sliding engagement with said surface covering, and means for cooling said wall.

' 6 4. Cooling'means for seals of wrapped packages cornprsing a metallic wall having a trifluorochloroethylene polymer surface covering on the outer face thereof, means for moving seals of Wrapped packages into sliding engagement with said surface covering, and means for cooling said wall.

5. Cooling means for seals of wrapped packages comprising `a metallic wall having a wax repellent synthetic resin surface covering ply secured on the outer face thereof, said covering ply being thin relative to the thickness of said wall, means for moving seals of wrapped packages into sliding engagement With said surface ply, and means for cooling said Wall.

6. Cooling means for seals of wrapped packages comprising a metallic wall having a polytetrafluoroethylene ply secured to the outer face thereof, said polytetrauoroethylene ply being thin relative to the thickness of said wall, means for moving seals of wrapped packages into sliding engagement with said polytetraiiuoroethylene ply, and means for cooling said wall.

7. Cooling means for seals of Wrapped packages comprising a metallic wall having a polyethylene ply secured to the outer face thereof, means for moving seals of wrapped packages into sliding engagement with said polyethylene ply, and means for cooling said Wall.

8. Cooling means for seals of Wrapped packages comprising a metallic wall having a trifluorochloroethylene polymer ply secured to the outer face thereof, means for moving seals of Wrapped packages into sliding engagement with said triuorochloroethylene polymer ply, and means for cooling said Wall.

9. Cooling means for seals of wrapped packages comprising a metallic wall having a polytetraiiuoroethylene coating over the outer face thereof, means for moving seals of wrapped packages into sliding engagement with said coated face, and means for cooling said wall.

l0. Cooling means for seals of Wrapped packages comprising a metallic wall having a polyethylene coating over the outer face thereof, means for moving seals of wrapped packages into sliding engagement with said coated face, and means for cooling said wall.

11. Cooling means for seals of wrapped packages comprising a metallic Wall having a trifluorochlorethylene polymer coating over the outer face thereof, means for moving seals of Wrapped packages into sliding engagement With said coated face, and means for cooling said wall.

l2. Cooling means for seals of wrapped packages comprising a plurality of rectangular metallic conduits collectively forming a wall, said wall having a iiat face having a wax repellent synthetic resin surface covering thereon, said surface covering being thin relative to the thickness of the walls of said conduits, means for moving seals of wrapped packages into sliding engagement with said surface covering, and means for circulating a cooling medium through said conduits.

i3. Cooling means for seais of wrapped packages comprising a plurality of rectangular metallic conduits collectively forming a wall, said wall having a flat face having a polytetrafluoroethylene surface covering Lthereon, said surface covering being thin relative to the thickness of the walls of said conduits, means for moving seals of wrapped packages into sliding engagement with said surface covering, and means for circulating a` cooling medium through said conduits.

14. Cooling means for seals of wrapped packages comprising a plurality of rectangular metallic conduits collectively forming a wall, said wall having a flat face having a polyethylene surface covering thereon, means for moving seals of wrapped packages into sliding engagement with said surface covering, and means for circulating a cooling medium through said conduits.

15. Cooling means for seals of wrapped packages comprising a plurality of rectangular metallic conduits collectively forming a wall, said wall having a flat face hay- References Cited in the le of this patent UNITED STATES PATENTS sticelber sept. 7, 1937 Spalding June l2, 1951 "8 McGinley et al Aug. 14, 1951 Rubin May 12, 1953 Langer Apr. 13, 1954 Bergstein May 18, 1954 McGinley Dec. 21, 1954 Miner et al. Dec. 28, 1954 Stickelber June 14, 1955 FOREIGN PATENTS Great Britain Nov. 7, 1951