US2753092A - Closures for collapsible tubes containing paste - Google Patents

Description

y 1956 v. R. SMITH 2,753,92

CLOSURES FOR COLLAPSIBLE TUBES CONTAINING PASTE Filed Feb. 21, 1952 INVEN TOR. WAKE/VT 15? 5/14/76 ATTORNEY CLUSURES FOR COLLAPSIBLE TUBES CUNTAENING PASTE Vincent R. Smith, New Milford, N.

Application February 21, 1952, Serial No. 272,862

4 Claims. (Cl. 222--545) This invention includes a closure device attachable or attached to a tube containing a paste and not removed therefrom if at all until after the contents of the tube have been completely used. My device, therefore, takes the place of conventional caps which must be completely removed from such a tube every time a portion of a paste is extruded and often become lost. At best the replacement of these caps is annoying and almost invariably results in untidiness owing to a surplus of paste about the caps and the objects which they and the adjacent end of the tubes may touch. Inventors have long attempted to devise such closures. Such efforts, so far as I am aware, have been ineffective because of the high cost of pro duction, the presence of projecting parts which caused trouble in production, packaging and operation, structure such that methods of and machinery for tube manufacturing or filling must be changed, or design such that the paste is likely to dry and block a portion of a channel through which it is supposed to be freely extruded. A principal object of this invention is to provide such a closure device which overcomes these and other disadvantages of the prior art.

Another chief object of my invention is the production of a highly efficient threaded closure device adapted to be manufactured at an absolute minimum of expense and applied to existing tubes either by a consumer at a point of use or by a manufacturer at the point where the tubes are filled. This purpose therefore is to produce a simple closure which can be manufactured literallyfor a few mills which when applied to a tube remains thereon and serves as an efiicient closure until the entire contents of the tube are used. Thereafter it may be removed and used over and over again on other tubes. Alternatively, my closure device may be formed integrally with a tube and never removed therefrom. It is a matter of common knowledge that present separable caps for such tubes are very often lost with consequent waste of the materials within the tubes. Whether lost or not, their use results in surplus paste being smeared about the orifice of the tube and objects touched thereby, to the annoyane of neat users and careful housewives. According to this invention, paste is extruded from a side rather than the end of of the closure as is more convenient when the material is being placed upon a brush.

Another important characteristic of this invention in an easily-mountable closure which has the foregoing characteristics and advantages is provision of an entirely smooth inner channel, also having novel shape, from the point of atachment to a top of a cap, so that paste cannot clog and thereafter become dry and hard and hence clog the passageway. Another highly important object is to provide a simple two-part closure which is characterized by a single or multiple set of instrumentalities such as an annular ring or rings and cooperating annu-.

l at grooves for their reception which act both as a mounting for one of my two members upon the other thereof and as a complete and adequate seal for the closure. Thus Tnited States Patent I one set of means integral with my two separate parts elliciently accomplishes a double function.

Another important object of this invention, never before attempted so far as I am aware, is to provide in a tube and closure, which need not be bodily detached therefrom during use, structures and methods which automatically pull back into the tube the small amount of paste which even in a closure of this kind is extruded upon the orifice but not used. This object includes means and methods which suppress leakage from pressure previously applied. It is a matter of common knowledge that it is almost impossible for a user of a paste to squeeze out of a tube exactly the right amount and then to place all of the extruded paste upon a tooth or shaving brush, for example. An object of this invention is automatically and without material expense or without any expense whatsoever to pull this slight excess back into the tube so that when my closure has been used and is turned to closed position, no surplus remains exterior to the device. Even without the use of these means and methods my invention accomplishes in a practical manner longsought objects of the prior art, but with them it completes the accomplishment of these objects.

The business of manufacturing, packaging, selling and supplying tubes of paste is highly competitive. Consequently, a chief object of this invention is to accomplish all or the first-stated portion of these objects at a minimum cost, whether my device is distributed separately for application as by a child or mechanically unskilled house wife and without the use of tools, or is applied interchangeably with the present type of caps in a factory or formed integrally with the body of the tube.

Other objects, advantages and characteristics will be evident from the following portion of this specification, the accompanying drawings and the subjoined claims. Although I am showing preferred forms only of my invention, it will be understood that changes can readily be made without departing from the scope of my broader claims or the spirit of my invention.

In the drawings:

Figure 1 is a side elevational view of the entire subject matter of a major form of my invention.

Figure 2 is a side elevational view partly broken away and in section corresponding to the upper portion of Fig ure 1 and .showing only the inner of the two members of my invention.

Figure 3 is a top plan view corresponding to Figure 2.

Figure 4 is a side elevational view corresponding to Fig-. ure 2 and showing the outer of the two members of my closure.

Figure 5 is a top plan view corresponding to Figure 4.

In all figures for clarity the size of the closure in relation to that of the tube is somewhat exaggerated.

For convenience in this specification and in the subjoined claims orientation is that of the figures. By top and bottom, it will be seen, I mean respectively the portion of the tube of paste or cap which has the orifice and the one opposite thereto. Upper and lower have a corresponding significance. Vertical indicates a di rection from the top to the bottom of the tube or of my closure. The significance of inner and outer is obvious. Like terms are used with like meanings.

The portion of my invention making up the closure consists of two members only, an inner or discharge member attached, removably or otherwise, to the tube, and an outer member largely embracing and rotatable upon the inner member. As shown for purposes of illustration, this inner member is screwed to the thread ordinarily formed on the top of a tube of paste thereby taking the place of a conventional removable cap, but it may be permanently joined to the tube. I much prefer to mold each of these parts from a synthetic resin which is resilient, at least slightly, but I may employ a suitable metal provided it is somewhat elastic, for reasons later appearing. Only one of the two members, preferably the outer, need have this resilience. Alternatively, under some circumstances and less desirably, I may manufacture the outer member in two parts which are joined to each other after assembly with the inner member. In this case resilience is not necessary.

My invention as a whole will be understood by consideration of Figure l with reference to the other figures hereof for showings of detailed structure. To a tube 11 having upper shoulders 13 and a male thread 15 I apply my novel closure generally designated as 17 (Figure I). If the full advantages of my invention are to be enjoyed, a vacuum or open space 19 at the bottom of the tube is provided. The formation of this open space or vacuum requires no material change in present practice. As is well known in this art tubes of paste are filled from the bottom and thereafter the bottom end of the tube is turned over upon itself and the sides pressed together to form a seal as indicated at 20. In my tube between this seal and the body of the paste a small open space is left, the expulsion of air thus generally creating a partial vacuum for purposes later to be described. Alternatively, as hereinafter set forth, in place of this prefabricated open space, a user may readily accomplish at least a portion of the same result by manipulating a tube which has been conventionally filled. Before describing this featurfe of my invention I shall present my closure device itsel In the practice of my invention, as previously explained, I prefer to utilize a material, preferably but not necessarily plastic, which has a slight amount of resilience, the resilience of this material in cooperation with the hereinafter described construction accomplishing a result superior to that ordinarily achieved by the more elaborate and less satisfactory designs of the prior art.

My closure includes an inner or relatively fixed discharge member generally indicated as 21. This element is provided with a central vertical opening 23 which is completely smooth and without protrusions on its inner side which would cause clogging of the paste. Thus a completely smooth and unbroken channel is provided. Upon its lower portion this member is formed with a female interior thread 25 which engages the previously-described male thread 15 of the top of the cap. An orifice 27 in vertical wall 28 shown at one side provides for the extrusion of the paste. Alternatively, an orifice offset from the longitudinal axis of this opening could be found in the top wall 30. For purposes presently to-appear the top 31 of the inner member is inclined upwardly away from the orifice.

An important element of this invention is an annular ring 33 formed on the exterior of this inner member and slightly protruding from wall 28. For simplicity I show only one ring but in practice I may use a plurality, say two or three, each of course parallel to the other or others and in a plane normal to the longitudinal axis of the structure. A stop 35 extends outwardly, likewise in a plane normal to said axis, and is preferably molded integrally with the inner member. I show stop 35 as oblong with rounded corners, but it may be made in any practicable shape which is suitable for a casting or molding operation. This entire structure, as previously stated, is preferably molded at one operation from a synthetic resin.

The outer or cap member generally indicated as is complementary to and largely encloses inner member 21 as clearly seen in Figures 4 and 5. An inner opening 41 the principal axis of which aligns with the vertical axis of the tube is so positioned and dimensioned as to receive the inner member and closely engage the outer wall thereof. This opening 41 is bounded by a vertical wall 42 unbroken except for an annular groove 43, this groove eing of great importance in the practice of this invention, and an orifice 45. This groove receives and closely engages and cooperates with annular ring 33 of the body member previously described. It is, of course, to be understood that the relative positions of annular groove and annular ring may be transposed. It is important to note that the outer diameter of body member 21 and the inner diameter of cap member 40 are almost exactly the same, the relatively greater diameter of the outer opening being a matter of only a very few thousandths of an inch at most, even .0005. In fact, owing to the elasticity of the mating parts, the outside member may be slightly smaller. The cap member is supplied with a chamfered orifice 45 cooperating with opening 27 in the body member. A lower cut-out 49, say of degrees, receives stop-pin 35 mounted upon or formed with the inner member.

If desired the outer wall 51 of the top 53 of the outer member may be knurled, but this expedient is not necessary because when my closure is operated freedom from excess paste on the outer wall makes it practicable for the user so firmly to grasp the entire outer member that the assistance of the knurled surface is superfluous.

The assembly of my device is most simple. A worker merely pushes cap 40 over body member 21, the resilience of walls 28 and 42 being such that these walls give sutficiently so that the annular groove 43 slips into the annular ring 33. Thereupon assembly is complete. This ring and groove thereupon form both a seal against the exudation of paste and a guide upon which the outer member rotates. For rapidity of assembly a simple jig may be provided, or, alternatively, this operation of pushing one member on to the other in quantity production may be done by automatic machinery. Although simple and quick when carried out by hand operation, use of automatic machinery is desirable.

When a user is supplied with my device in this form he merely unscrews the cap which is provided with an ordinary tube, throws it away and screws my closure device on the thread previously used for the discarded cap. As a matter of practice, he screws my device on relatively tightly, but my closure, even when not tightly screwed in place, is operated by so little force that it is really not necessary to worry about the closure becoming loose from the top until the contents have been exhausted and the user wishes to remove it preparatory to placing it upon another tube. It is of course obvious that my closure may either be sold as a separate item or furnished with tubes supplied by a manufacturer, in the latter case taking the place of the usual cap.

I have shown my closure device as an independent unit adapted to be used repeatedly upon any tube of paste the top of which. is supplied with a conventional screw thread. Alternatively, my closure may be applied at the factory as a permanent part of a tube. Under such conditions threads 15 and 25 need not be supplied and the closure is permanently attached to the neck 13 of a tube. The cost is little more than that of the conventional screw cap and its threaded mounting.

The use of this phase of my invention will have been made clear by the foregoing description. In operation a user merely turns outer cap 40 until the orifices 27 and 45 are in alignment, the stop and the end of its opening having engaged, and then squeezes the tube so that the desired amount of the paste is extruded. He closes the tube merely by rotating the cap so that the orifices are not in alignment. Preferably the threads are so arranged that 1 opening movement is counter-clockwise and closing movement clockwise, as with a conventional threaded cap. Thus no established psychological pattern in the user need be broken. The seal caused by annular rings 33 and annular grooves 43 serve both as the mounting for the outer seal.

If desired, another important element may be practiced as a part of this invention. I have discovered that if an open space or partial vacuum is supplied at the bottom of the tube after the paste is extruded through the aligned openings and before the cap is rotated to closed position, the small amount of paste exterior to the aligned openings is forced back into the tube, thus removing from the outer orifice even the slight quantity of paste which might remain there. The smooth nature of the entire channel through which the paste moves makes this operation possible. It appears probable that this result is accomplished by greater air pressure upon the paste at the opening than upon the paste at the bottom of the column. Also it is possible that when ample space is left at the bottom of the tube the cohesive quality of the paste pulls back this slight surplus, no doubt assisted by air pressure. Whatever the exact physics of the operation it is highly useful in avoiding even a small surplus at the outer orifice.

If desired, therefore, the tube to which my invention is applied may be filled at the factory with a vacuum or open space or chamber 19 at the bottom thereof, thus realizing the full advantages of my invention from the outset of its use. Alternatively, however, I have discovered that the user himself after the use of a very small quantity of the contents of a conventional fully filled tube may enjoy all of the advantages of the practice of the full invention. The purveyors of pastes often recommend that as the paste is used, the end of the tube be rolled back upon itself so that there is a firm foundation as it were for the column of the paste remaining. In the full practice of this invention, however, with a tube completely filled at a factory a contrary method is employed. A user always leaves a small portion of the lower part of the tube untouched after the paste is extruded therefrom thus providing a small space with at least a partial vacuum into which excess paste may be pulled back. The user may wind up the lower edge of the tube as he is urged to do at present so long as he leaves a small space free from paste. If, however, a large unoccupied space is left at the bottom, as relatively large quantities of the paste are used, this result is not obtained.

Thus it is possible without departing from established manufacturing practice for a user without difficulty to create an open space or partial vacuum as he proceeds to use the contents of a tube and substantially completely avoid even a slight excess of paste at the point of closure. I emphasize that the use of my closure is in no way dependent upon the provision of this open space. I have found that this method does not operate with closures from which the paste is extruded other than at substantially a right angle to the vertical axis of a tube.

As stated, I prefer to incline the top wall 31 of inner member 21 upwardly from a point adjacent the top of orifice 27 to its junction with the top of the opposite portion of side wall 28. l have found that this configuration is of assistance both in the step of drawing back into the tube a slight excess of paste left around the opening and also in the optimum operation of my device even when a partial vacuum is not employed. With an inclined upper wall there is less tendency for even a slight surplus of paste to be extruded at the time pressure is released. Also, in my device when the orifice is opened and before pressure is applied no paste is extruded. In tubes with conventional closures, however, pressure remaining from a previous operation is likely to expell a small quantity of paste as soon as a cap is removed. in the ordinary operation of pressing paste out of a tube after pressure is relaxed it is usual that a small amount of paste exudes. This amount even without this inclined wall is less in my device than in a tube provided with a conventional closure but this slight surplus is reduced almost to the vanishing point when this top wall is slanted in this manner. My explanation of what has been found to happen is that the angular cavity created by the rightward junction as shown in Figures 1 and 2 of top wall 31 and the inner surface of wall 28 does not become completely filled owing to the easier egress of the paste through the opening 27 while pressure upon the tube 11 is maintained, but does serve as a place of deposit for excess which otherwise would be forced outwardly. Apparently repeated use of the tube with my closure does not completely fill this excess space.

The advantages of my invention will be clear from the above portion of this specification, the drawings attached hereto and made a part hereof and the subjoined claims. These advantages include the provision of an inexpensive and efiicient closure for tubes of paste and means and method of removing from the orifice of the closure all but a mere trace of paste which has been extruded and not used.

I claim:

1. A closure device consisting of an inner cylindrical member having a central opening with a vertical wall and an orifice at right angles to such opening, said inner memher being adapted to be attached to the top of a collapsible tube, an upper wall bounding the top of said opening, said upper wall being inclined from a line adjacent the top of said orifice upwardly to a junction with said vertical wall opposite to and above said orifice, an outer cylindrical member fitting over said inner member and rotatable thereupon and having an orifice which upon such rotation is aligned with said orifice of said inner member, and means for mounting said outer member upon said inner member.

2. In a closure device for tubes containing paste, an inner cylindrical member and an outer cylindrical member, said inner member being adapted for attachment to an orifice in the top of a tube of paste and having a central cylindrical vertical discharge opening alignable with said orifice of said tube and an orifice communicating with said discharge opening, the upper wall of said central opening being inclined from a line adjacent the top of said orifice upwardly to a junction with the inner wall of said opening opposite to and above said orifice, said outer member having a central opening adapted to receive therewithin substantially all of said inner member, the exterior walls of said inner opening and the interior walls of said outer opening being disposed closely adjacent each other and at least one of said walls being slightly resilient, annular mounting and sealing formations disposed circumferentially of each of said walls in a plane normal to said openings, one of said formations being male and the other being female, said resilience being sufiicient so that when said outer member is forced upon said inner member said formations engage and said outer member is firmly held against bodily movement away from said inner member and may be rotated thereupon to bring said openings into alignment, a stop member projecting from one of said members toward the other thereof and entering a cut-out portion of said wall of said other member, the length of said cut-out portion thereby limiting the rotation of said member relatively to said inner member.

3. As a new product of manufacture, a collapsible tube and operable closure means therefor; said collapsible tube having a side wall and including permanent closure means at the bottom thereof wherein the opposite parts of said side wall of said tube are pressed closely together, a space free from paste being disposed between said permanent closure means and the bottom of a column of paste within said tube and a neck being disposed at the top of said tube above the column of paste in said tube, said neck being provided with an opening; said closure means comprising a clear channel upon a vertical axis leading from the opening of said neck at the top of said column of paste within said tube to an orifice at right angles to said vertical axis of said tube, an inner vertical wall bounding said opening, an outer vertical wall mounted for rotation upon said inner wall and closely adjacent thereto, an orifice disposed in said outer wall which may be brought into alignment with said orifice in said inner wall upon the rotation of said outer wall upon said inner wall whereby an opening is provided and brought out of alignment by rotation of said outer wall so that a solid portion thereof is disposed opposite said inner orifice, the diameters of said orifices being much less than that of the opening of said neck, said walls being disposed closely adjacent each other, and an upper wall disposed adjacent said inner wall near the top thereof and bounding the inner upper portion of said closure means, said last mentioned wall extending between opposite sides of said vertical inner wall generally horizontally but inclined at an angle extending downwardly toward the upper portion ofthe orifice of said wall thus providing a recess, a slight surplus of paste which is left adjacent the outer portion of said orifice after paste has been extruded after saidorifices are in alignment being moved back inwardly of said tube into said recess and operable closure.

4. A closure for a tooth paste tube comprising an inner tubular cap element having an egress part and being adapted to be attached to the neck of said tube and extend therefrom, an outer tubular cap element slidable axially over said inner element and having an egress part registrable with said first mentioned egress part, and being rotatable on said inner element to align said parts, one of said elements having a circumferential groove and the other of said elements having a circumferential ridge slidably and sealingly fitting in said groove, said ridge and groove coaction serving to join said elements and to maintain a seal therebetween wherein said outer element is supported on said inner element, at least one of said elements being resilient whereby said elements may be joined by telescoping one into the other so that said ridge snaps into said groove and is resiliently held therein,

References Cited in the file of this patent UNITED STATES PATENTS

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