PACKAGING TUBE AND METHOD

Abstract: Packaging for elongated articles comprises a thermoplastic tube having radially inwardly and outwardly displaced wall portions providing an effective wall thickness greater than the actual thickness of the tube wall, with the ends of the tube being pinched and fused together at a transverse flange (42, 44) to provide a hermetically sealed package. Several embodiments of tube configuration are disclosed.

Description: Description PACKAGING TUBE AND METHOD Field of Invention This invention relates to article packaging and methods of effecting same. Background of Invention For many years it has been the practice to package, particularly elongated articles, in paperboard tubular containers. On occasion, if these tubes were twisted the wrong way, they would tend to unwrap. To render them waterproof or moisture resistant, the tubes had to be coated with an impervious barrier, and were often difficult to open without danger of injuring the contents. In general, the tubes provided no appreciable shock cushioning for the contents in the event the tubes were dropped unless the article was embedded in a cushioning material deposited in the tube. As the cost of this type of packaging has risen and because of its non-reusability, there has been an increasing need for a low cost packaging for elongated articles, preferably a packaging which may be reusable. There has also existed the need for packaging for elongated articles which will protect or support the articles against damage though the package is dropped without the necessity ' of adding cushioning material inside the tube. Heretofore there have been suggestions that the package contain cushioning blocks such as shown in U.S. Patent 3,938,661, and the prior art also includes styrofoam blocks which have been molded to conform to the shape of an article for supporting articles in various shaped outer packages. The expense of such styrofoam blocks has increased the cost of article packaging. In addition, there has been a need for a simple and inexpensive package by which elongated articles, such as crankshafts, camshafts, and the like, used in the manufacture • or repair of automotive engines, may be packaged for shipment and storage where the shafts will be protected against damage and hermetically sealed against the environment. There has also been a need for such packaging for automobile antennas, automotive side moldings and the like, which may be easily distorted until mounted on the vehicle. Finally, there has been the need for a package that may be readily opened without danger of damaging the article contained therein. Summary of the Invention I have conceived of a package and method of packaging particularly suited for elongated articles or articles arranged in an elongated stack, comprising an elongated tube of plastic material having a wall shaped to ■exhibit radially inwardly and outwardly displaced wall portions extending along the length of the tube to provide a tube wall having an effective radial thickness greater than the thickness of the wall material itself with the inwardly and outwardly displaced wall portions providing cushioning support for an article disposed within the tube if the tube with the article therein should be accidentally dropped or otherwise subjected to external shock loading. The ends of the tube are pinched closed and the plastic fused together. Thus a hermetically sealed package may be provided. The diameter of the tube may be sized in relation to the article to be packaged so that the wall portions which are inwardly and outwardly displaced may serve to closely embrace the article to prevent its movement within the tube. In addition, the pinched ends provide opposed tapering sections between which the article is trapped and cushioned should the tube be dropped or receive a blow on its end. At the pinched ends where the plastic is fused, a flange is provided further reinforcing the tube and providing an area for product identification. According to a preferred method, the tube is extruded from a thermoplastic material, cut to a length exceeding that of the article to be packaged, one end of the tube is pinched closed with the plastic being fused, the article (or articles) then inserted in the tube against the pinched end, and the opposite end of the tube is pinched and the plastic fused to encapsulate the article within the tube. To open the package the tube is simply cut transversely across in a tapered end (where the cut will be beyond the end of the article) and the article extracted. Brief Description of the Drawings Fig. 1, is a cross-sectional view through one of my packaging tubes taken along the line 1-1 of Fig. 2; Fig. 2 is a side elevation of a packaging tube embodying my invention prior to closing the ends thereof; Fig. 3 is ' a side elevation of the tube of Fig. 2 showing an elongated article contained therein in- phantom outline and with the opposite ends of the tube pinched closed; Fig. 4 is a plan view of the package shown in Fig. 3; Fig. 5 is a side elevation of a second embodiment of my invention; Fig. 6 is a plan view of the embodiment shown in Fig. 5; Fig. 7 is a cross-sectional view taken on the line 7-7 of Fig. 5; Fig. 8 is an end view of the package shown in Fig. 5 ' Fig. 9 is a side elevation of a third embodiment of the invention; Fig . 10 i s a pl an vi ew of the inve nt ion shown in Fig . 9 ; Fig . 1 1 i s a cros s-s ectional vi ew take n on the line 11-11 of Fig . 10 ; Fig. 12 is an end view of the package shown in Fig. 9; Fig. 13 is a side elevation of a fourth embodiment of the invention; Fig. 14 is a plan view of the embodiment shown in Fig. 13; Fig. 15 is a cross-sectional view taken on the line 15-15 of Fig. 13; Fig. 16 is an end view of the embodiment of' the invention shown in Fig. 13; Fig. 17 is a plan view of a fifth embodiment of the invention; Fig. 18 is a side elevation of the embodiment shown in Fig. 17; Fig. 19 is a cross-sectional view taken on the line 19-19 of Fig. 18; and - Fig. 20 is an end view of the embodiment shown in Fig. ' lδ. Brief Description of Preferred Embodiments n Eigs. 1-4 I have shown a preferred embodiment of the invention wherein an elongated generally cylindrical tube 30 of plastic material has the tube wall shaped to exhibit radially inwardly and outwardly displaced wall portions or corrugations, respectively 32 and 34, which extend along the length of the tube to provide a tube wall having an effective radial thickness T greater than the thickness of the wall material itself. The effective wall thickness T may be approximately four times the actual thickness of the wall itself. Of course, the effective wall thickness T may vary depending upon the characteristics desired in the tube. The circumaxial width C of the corrugations may also vary in accordance with the designer's requirement. In the embodiment shown, the corrugations are at such a circumaxial width that a camshaft 36 disposed within the tube will have its cam lobes 38 and 40 partially nesting within the circumaxial width of the corrugations, thus preventing the camshaft from rotating relative to the tube. Thus, the circumaxial width of the corrugations, as well as the internal diameter of the tube measured from the peaks and valleys of the corrugations, may be related to the diameter of the article being packaged. While I have shown in phantom outline a camshaft, obviously many other forms of elongated articles may be packaged. Not all articles may lend themselves to interfitting or nesting with the corrugations as does the camshaft 36 of Fig. 1. For example, in the packaging of small antennas for radios, such as may be used in automotive vehicles, the antennas may or may not be disposed for nesting relationship with the corrugations. ' The tube 30 is preferrably formed of low density linear polyethylene. This material is readily fusible by sonic welding and may be extruded utilizing conventional extruding machines with suitable extrusion dies. Other thermoplastic materials may also be used in accordance with the requirements of the particular application. In a prototype embodiment found satisfactory for packaging internal combustion engine camshafts, the wall material was approximately .050 to .055 inches thick with an effective wall thickness T of approximately .200 inches. Opposite ends of the tube are preferrably closed as shown in Figs. 3 and 4 by pinching the tube wall and fusing the plastic, as by sonic welding, to form flanges 42 and 44. The flanges provide a convenient flat surface to identify the article contained within the tube as on flange 44 in Fig. 4, and/or a trademark as _on flange 42. In addition, one or both flanges may be provided with an aperture 46 to enable the tube to be hung on a display rack or provided with an identity tag. The flanges 42 and 44 serve to materially strengthen the tube diametrically and also serve as a bumper if the tube is dropped on an end. It will be noted that the tube tapers as at 48 and 50 to the flanges 42 and 44, and the camshaft or other article 36 contained within the tube may abut the inside of the tapers 48 and 50 to hold the article against longitudinal displacement relative to the tube. As a result, if the tube is dropped accidentally end-first, the article will have the shock cushioned, first, by the radially inwardly extending convolutions of the corrugated wall and, second, by the tapered shape 48 or 50 against which the force of the article will be absorbed. • In addition, the flanges 42 and 44 project laterally across the diameter of the tube as best shown in Fig. 4, as well as project longitudinally as best shown in Fig. 3, and serve as a bumper should the package be dropped end-first on a hard floor. The flanges 42 and 44 will have a thickness approaching that of twice the thickness of the wall material. While the flanges are shown as flaring slightly in Fig. 4, it is possible to form them during fusing of the plastic so that they, in fact, do not exceed the outside diameter of the tube. However, " by providing the flanges 42 with a width as shown in Fig. 4 exceeding the outside diameter of the tube, the flanges may serve to support the tube in suitable racks (not shown) if the tube is to be stored in a rack-like structure for transportation or inventory purposes. In practice, the tube 30 will be extruded and cut to length somewhat exceeding that of the article to be packaged. One end of the tube is then pinched closed and the plastic fused to form a flange, such as the flange 42 in Figs. 3 and 4. Thereafter, the article to be packaged is inserted in the tube through its open end and then the open end is pinched and the plastic fused, thus forming, for example, the flange 44. At this time the flange may be stamped with suitable part indicating information as shown in Fig. 4. If desired, the formation of the flanges 42 and 44 may serve to seal hermetically the interior of the tube and thus exclude the environment from contact with the part or parts contained therewithin. In addition, at the time the part, such as a camshaft 36, is inserted into the tube, a suitable dessicant or an inert gas may be injected into the tube to help preserve the part contained therein and thereafter the tube end sealed to provide a hermetically sealed package. When it is desired to use the article contained within one of the packaging tubes, it is only necessary to cut the tube transversely in the area of the taper beyond the end of the article and the article removed. Thereafter, the tube may be ground up and remelted to be reextruded into a new tube for further use. Thus, the tube is reusable. Application of this feature will be particularly advantageous where a manufacturer of articles may package them in tubes, close the open end, and thereafter ship the tubes with the articles contained therein to a point of use. At the user's location, the tubes may be opened, the articles removed, the tubes then ground up and the ground plastic returned to the original manufacturer where the ground plastic may be remelted and extruded into new tubes for further use. In Figs 5-8 inclusive I have shown a second embodi¬ ment of .my invention. In this case the corrugations of the generally cylindrical tube 56 are not of uniform circumaxial width as they were in the first embodiment. Here, radially outwardly displaced corrugations 52 are substantially twice the circumaxial width of the radially inwardly displaced corrugations 54 of the tube. As with the first embodiment, the tube tapers, as at 58 and 60, to form the flanges 62 and 64 where the material of the tube wall is fused together. As with the first embodiment, the internal diameter and circumaxial width of the corruga¬ tions may serve to accept in interfitting relation (not shown) articles introduced into the tube. Initially, following extrusion and cutting of the tube to length, one end of the tube would preferably be pinched and fused together and thereafter the article introduced into the tube and then the open end pinched and fused to form a hermetically sealed chamber. In Figs. 9-12 inclusive I have shown a third embodi- ment of the tube indicated at 66, wherein in cross-section the tube is generally square and where the inwardly and outwardly displaced wall portions 68, 70 and 72 are of different configuration, different radial displacement and different shape. The major outwardly displaced portions are disposed at the corners of the generally square shape as indicated at 68, 68', 68'*, and 68 1 ' 1 . Intermediate these corners are inwardly displaced corrugations 70, 70', 70' ', 70' ", etc. Intermediate these inwardly displaced portions are the radially outwardly displaced portions 72, 72', 72' ' and 72' 11 . This particular tube configuration lends itself to packaging in square or rectangular spaces as the tubes may be at least partially nested, and also has the virtue of resisting rolling if one of the tubes is laid on a workbench or the like. The tube 66 terminates at opposite ends in flanges 74 and 76 with the tube tapering to such ends. In Figs. 13-16 inclusive I have shown a fourth embodiment of the packaging tube at 78. As best shown in Fig. 15, the tube has a generally square exterior and cylindrical interior with generally radially outwardly displaced portions 80, 82, 84 and 86 and inwardly displaced portions 88, 90, 92 and 94. As depicted, these inwardly and outwardly displaced portions form enclosed chambers 96, 98, 100 and 102 at the corners of the generally square exterior configuration of the tube. The corner chamber 98 is typical of all four and includes inwardly displaced corrugations 106 and 108 and outwardly displaced corrugations 110 and 112. The corner chambers are connected by intermediate wall portions of the tube 114. The chambers 96, 98, 100 and 102 may be hermetically sealed and form effective shock-absorbing chambers in the event the package is dropped or struck on the corners. Opposite ends of the tube are closed by pinching and fusing the plastic as shown at 116 and 118 where flanges are provided to further cushion shocks should the package be dropped on its end or struck from the end. It will be noted that the corrugations 106, 108, 110 and 112 extend longitudinally of the package along both the inner and outer walls to strengthen and reinforce the package longitudinally, i.e., help the package to resist bending from pressure applied perpendicular to its longitudinal axis. In Figs. 17-20 I have shown a fifth embodiment of the packaging tube. Here the tube has radially outwardly displaced corner portions 120, 122, 124 and 126, and inwardly displaced portions 128 in the form of a cylinder. The portions 120, 122, 124 and 126 form, in combination with the inwardly displaced cylindrical portion 128, four closed chambers 130, 132, 134 and 136 which, as in the embodiment of Figs. 13-16, may provide a cushioning effect should the package be struck on the corner. The opposite ends of the tube are pinched and fused as at 138 and 140 to provide flanges as before described and a hermetically sealed chamber enveloping the part (not shown) in the tube.

Claims: Claims What is claimed is: 1 . A packaging tube comprising : an elongated tube of plastic material; the wall of the tube being shaped to exhibit radially inwardly and outwardly displaced wall portions extending along the length of the tube to provide a tube wall having an effective radial thickness greater than the thickness of the wall material itself; and the ends of the tube being pinched closed. 2. The invention defined by claim 1 in which the ends of the tube are pinched closed and the plastic fused together. 3. The invention defined by claim 1 in which the ends of the tube are pinched closed and fused together forming a flange extending longitudinally of the tube and transversely across the ' lateral dimension thereof. 4. The invention defined by claim 2 or 3 in which the wall of the tube at opposite ends is gradually tapered radially inwardly to close the tube. 5. The invention defined by claim 1 wherein the inner wall surface portions of the tube spaced radially inwardly from adjacent outwardly displaced wall portions provide cushioning supports for an article disposed in the tube. 6. The invention defined by claim 5 wherein the ends of the tube at the ends of the taper are pinched together and the plastic fused. 7. The invention defined by claim 1 wherein the plastic material of the tube is a thermoplastic. 8. The invention defined by claim 1 wherein the tube wall is corrugated in cross-section and the ends of the tube are pinched and fused together. 9. The invention defined by claim 8 wherein the tube is generally cylindrical. 10. The invention defined by claim 8 wherein alternate corrugations are of a greater circumaxial width than the corrugations intermediate them. 11. The invention defined by claim 8 wherein some of the corrugations have . a greater radial outward projection than other of the corrugations. 12. The invention defined by claim 11 wherein the tube is generally square in cross-section with the corrugations of greater outward radial dimension being located substantially at the corners of the square and the corrugations of a lesser radial outward dimension being intermediate the corners. 13 * Tne invention defined by claim 1 wherein the tube wall includes an inner cylindrical portion and an outer rectangular portion with said portions integrally connected at intervals circumferentially about the tube. 14. The invention defined by claim 13 wherein the inner and outer wall portions include longitudinally extending corrugations. 15. The method of packaging elongated parts comprising the steps of: extruding a thermoplastic tube having longitudinally extending circumferentially spaced corrugations wherein inner wall surfaces of the corrugations provide cushioning support for articles to be placed within the tube; cutting the tubular extrusions to preselected lengths greater than the length of the article to be packaged; pinching closed one end of the tube and fusing the pinched wall to form a flange; inserting the article to be packaged longitudinally within the tube to rest against the closed end; and pinching the opposite end of the tube together and fusing the plastic to form a flange ^ 16. The method of packaging articles comprising: extruding a thermoplastic tube having a wall shaped to exhibit radially inwardly and outwardly displaced wall portions along the length of the tube whereby the tube wall has an effective radial thickness greater than the thickness of the wall material itself; pinching closed one end of the tube and fusing such end together forming a flange; inserting an article to be packaged in the tube; and pinching together the opposite end of the tube and fusing it to form a flange. 17. The invention defined by claim 16 wherein the second mentioned pinching together of the tube to close the end -is positioned so that an article disposed within the tube is trapped against longitudinal movement between the pinched ends. 18. The invention defined by claim 15 wherein the dimension of the tube diametrically across corrugations is in such relation to a diameter of the article to be packaged that the article interfits between opposed corrugations of the tube to prevent rotation of the article within the tube. 19. The invention defined by claim 1 in which the tube is hermetically sealed. 20. The method of packaging articles comprising the steps of: extruding a thermoplastic tube having a wall shaped to exhibit radially inwardly and outwardly displaced wall portions along the length of the tube to provide a tube wall having an effective radial thickness greater than the thickness of the wall material itself; pinching closed and fusing one end of the tube; inserting the article to be packaged within the tube; pinching and fusing closed the opposite end of the tube; transporting and storing the tube and packaged article; cutting open an end of the tube and removing the article therefrom; comminuting the tube and cut end; shipping the comminuted tube to a location for repackaging; and melting the comminuted tube and extruding another tube to repeat the method. 21. The method of packaging elongated parts comprising the steps of: extruding a thermoplastic tube having longitudinally extending circumferentially spaced corrugations wherein the inner wall surfaces of the corrugations provide cushioning support for articles to be placed within the tube; cutting the tubular extensions to preselected lengths greater than the length of the article to be packaged; inserting the article to be packaged longitudinally within the tube; and pinching closed opposite ends of the tube and fusing the pinched wall to form a flange. 22. The method of packaging articles comprising: extruding a thermoplastic tube having a wall shaped to exhibit radially inwardly and outwardly displaced wall portions along the length of the tube whereby the tube wall has an effective radial thickness greater than the .thickness of the wall material itself; cutting the tube to preselected lengths greater than the length of articles to be packaged; inserting the article to be packaged longitudinally within the tube; and pinching opposite ends of the tube together and fusing the plastic.

Inventors: CARROLL HAZEN J, CARROLL, HAZEN, J.
Applicants: CARROLL HAZEN J, CARROLL, HAZEN, J.
Application year: 1985
Main classification: B65D81
IPC codes: B65D81