US2700491A - Self-sealing dispenser cap - Google Patents

Description

Jan. 25, 1955 E. P. BOTTOMLEY 2,700,491

SELF-SEALING DISPENSER CAP Filed May 11, 1953 2 Sheets-Sheet ,6 I. I l a ||m// /NVENTOR Edward P Bo/tom/ey ATTORNEYS Jan. 25, 1955 E. P. BOTTOMLEY 2,700,491

SELF-SEALING DISPENSER CAP 1 Filed May 11, 1953 2 Sheets-Sheet 2 INVENTOR EDWARD. P BOTTOMLEY BY s p?? ATTORNEY SELF-SEALING DISPENSER CAP Edward P. Bottomley, Burlington, Vt.

Application May 11, 1953, Serial No. 354,070

'6 Claims. (Cl. 222-490) This invention relates to self-closing closures or caps for collapsible containers from which the contents is extruded by the application of pressure upon the body of the container, such as are commonly used for tooth paste, shaving cream, lubricants and similar substances.

The present appplication is a continuation-in-part of my copending application, Serial No. 126,180, filed November 8, 1949, now abandoned.

In commercial practice, collapsible containers such as are used at the present day for tooth paste, shaving cream, or the like have threaded caps which must be removed from the container before the contents can be used. These caps are easily dropped and lost or are merely forgotten so that the containers are frequently left uncapped with the result that the contents of the tube become hard and open to dirt and germs. This removable cap is a long recognized nuisance and many efforts have been made to eliminate it. In some tubes the cap is fastened to the tube so that it cannot be wholly separated from the tube, but for one reason or another these attachments have not proven successful.

The many advantages of a self-sealing closure or cap for such tubes are apparent and some efforts have been made to provide such a closure, but these efforts have not gone into any substantial commercial use. Examples of such efforts to provide such a closure will be found in United States Letters Patent No. 1,881,488 issued October 11, 1932 to G. A. Gleason, No. 1,991,126 issued February 12, 1935 to B. L. Stevenson, No. 2,012,950 issued September 3, 1935 to D. J. Block, and No. 2,067,196 issued January 12, 1937 to G. Lateur. It has also been suggested to use rubber sleeves or caps for the tube and to squeeze the tooth paste or cream from the rubber sleeve or cap but such sleeves or caps do not form a suificiently tight seal to prevent substantial leakage of the contents, or dehydration and contamination because of exposure of the contents to air.

A satisfactory self-sealing closure for such tubes should be sufficiently strong to prevent leakage of the contents, yet not unduly hinder the dispensing of the contents, and one of the objects of the present invention 1s to provide a cap or closure which eliminates the necessity of removing the cap when dispensing the contents and which completely and automatically closes the open1ng through which the paste is dispensed when it is no longer in use.

Another object of this invention is to provide a cap or closure for a collapsible container which permits d1spensing the contents of the container in the desired manner and thickness and quantity by mere pressure on the tube and yet provides a sealed closure upon termination of the application of pressure.

One of the chief reasons that the so-called self-cleaning closure caps of the prior art have not been accepted commercially is that such prior art devices have been 1n-, effective to completely seal the closure upon termination of pressure upon the collapsible tube. The failure to,- effect a complete closure results in drying out of the portion of the tube contents adjacent the outlet open ng of the tube closure and jamming of the outlet opening of the cap in such a Way that it is necessary to remove the cap and clean it before it can be used again. It also results in oxidation of that portion of the tube contents thereby making such caps unsuitable for .use with medicines, lubricants and the like where oxidation is deleterious. Lack of a complete closure also makes such caps in feasible for use with medicinal salves and ointments 2,700,491 Patented Jan. 25, 1955 when the collapsible tube with which it is associated is not subjected to pressure.

It is also a primary object of the present invention to provide an effective self-sealing closure cap which is simple and inexpensive enough to enable commercial use thereof, through a novel utilization of structural design prmciples producing a highly effective outlet strucure.

I have found that the foregoing object can be best achieved by providing an outlet opening defined by spaced walls, at least one of which is rigidly secured at its edges with a flexible end which engages the end of the other of such walls to provide a sealed closure.

It is therefore, a more specific object of this invention to provide a self-sealing closure cap for collapsible tubes and the like wherein the discharge opening is defined by opposed wall members which, in the absence of applied pressure, are engaged to form a seal therebetween, and at least one of which is rigidly secured at its edges for almost its entire length and has a resilient free portion at its forward end abutting the forward end of said other wall member thereby providing a novel type of cantilever support for said resilient free end portion; and producing by this novel cantilever support an internal reactionary stress insuch one wall member which is effective to restore the resilient end of that wall member to its position in abutment with the end of the other wall member to effect closure of the discharge opening upon release of prssure upon the collapsible tube.

A further object is to provide a closure having resilient walls, the ends of which are normally in contact with each other under suificient internal stress to seal the tube, but which are readily forced apart by pressure on the collapsible tube to permit, discharge of the contents thereof and which return to closed position when the pressure on the tube is released.

A still further object of the invention is to provide a dispensing cap or closure which is inexpensive to manufacture and which is attractive in appearance.

Referring now to the drawings in which like reference numbers are used to indicate like parts:

Figure 1 is a perspective view of the closure embodying my invention applied to a collapsible container;

Figure 2 is a top plan view of the closure of Figure 1;

Figure 3 is a sectional view taken on line 3-3 of Figure 2;

Figure 4 is a side elevation of the closure shown in the previous figures;

Figure 5 is a plan view of a second and preferred embodiment of the present invention;

F gure 6 is a longitudinal sectional view of the self sealing closure cap of Figure 5 taken along the line 66 of Figure 5;

Figure 7 is an elevational view of the discharge end ofthe self-sealing closure cap of Figure 5, the discharge: end being at the left in Figures 5 and 6; and

Figures 8, 9, 10 and 11 are transverse sectional views: of the self-sealing closure cap of Figure 5, being taken: along the section lines 88, 99, 1010 and 1111, respectively, of Figure 5.

In the embodiment illustrated in Figures 1 through 4- of the drawings, 6 indicates a collapsible tube of the: character used for tooth paste, shaving cream, lubricants; and other substances. The tube 6 is provided with a. dispensing cap or closure indicated generally at 7 and the paste, cream or lubricant may be extruded in a tapev or strip like extrusion 8 through the discharge end of portion 9 also has an opening 12 which is axially aligned with bore 11 to provide a passage through which the paste or cream may be extruded.

The paste or cream from the tube 6 passes through the opening 12 into a chamber indicated generally at 13 in Figure 3. In the embodiment illustrated in Figures 1-4, this chamber 13 is formed by two rigid triangular members 14 secured on the outerflat surface of the body portion 9 in any suitable manner and in parallel space relationship on opposite sides of the opening 12. Flat, flexible strips 15 of plastic, spring steel, or any other suitable materials are also seemed to the body 9. between the members 14 one on each side of the opening 12. These strips 15 are of a width sufficient to fit between members 14 and are secured along almost their entire length to the edges of triangular members 14. The outer ends of strips 15, as exaggeratedly indicated at 16, are not secured to the members 14 but are left free. It is thus apparent that, the strips 15 being fixed at their marginal edges along the major portion of their length to the members 14, their free end portions are effectively cantilever supported. The resilient strips 15 are secured to the members 14 in such a manner that their extreme outer ends are normally urged into close contact as indicated at 17, thereby sealing the tube 6.

The resilience of the material of strips 15 and the length of the free end portions 17 are such that pressure on the tube 6 will cause the paste to force the end portions apart as shown in Figure 3 and permit the paste to be extruded in the tape or strip 8, but when the pressure is released, the free end portions 17 of strips 15 act like cantilever beams and are forced by the relatively high internal stress developed at the base of these free end portions to move back together as shown in Figure 2, thereby cutting off the tape or strip 8 and sealing the tube.

Referring to Figures -11 there is disclosed therein a modification indicated generally at 20, which is an improvement over the embodiment of Figures l-4, previously described herein, and disclosed in my copending application Serial No. 126,180.

Closure cap 20 is made from any suitable materials preferably a plastic material having relatively high strength and flexibility characteristics which may be readily molded. Closure cap 2t comprises a body portion 21 having a threaded bore 22 by which it can be secured to a collapsible tube such as tube 6 in Figure 1. The paste extruded from the tube 6 passes into a chamber 23 formed by two curved endwalls 25 and two substantially fiat side walls 26. All four of these walls extend from body portion 21 and are integrally secured thereto, preferably by molding them integrally with the body portion 21. As shown in the sectional views of Figures 8-11, curved end walls 25 extend substantially parallel to each other on opposite sides of the opening 23, progressively decreasing in width from their root portion at body 21 to their forward ends at 27. Side walls 26, however, converge to meet at the forward end 27 of closure cap 20. Surfaces 36 and 37 of the side walls 26 also converge so that side walls 26 have a progressively decreasing cross-section from their root portion 29 to their free end portions 30 to achieve an effective combination of strength and high flexibility in the side walls 26. The front end 27 of cap 20 is cut away at 32 between side walls 25 to form a very narrow slot 33, as shown in Figures 5-7. The forward edges of side walls 26 are provided with very narrow slits extending a short distance along each side as exaggeratedly indicated by lines 35 in Figure 5 to provide a pair of flexible reed-like free end outlet portions30 in abutting relation along line 33. Thus, side walls 26 are fixed along most of their marginal edges to end walls 25 so that their flexible reed-like ends 30'are efiectively cantilever supported.

When formed in this manner, reed-like free end portions 30 are normally urged into close contact as indicated at 33 thereby sealing the tube 6. The resilience of the material of side walls 26, their progressively reduced cross-section from their roots 29 to reed-like free ends 30, and the length of reed-like end portions 30 are such that pressure on the tube will cause the paste to force, the. end portions apart in a manner similar to the showing in Figure 3 and permit the tube to be extruded in a tapeor strip such as shown at 8 in Figures 1 nd u rw en the.p es urci e ea r dik free end portions 30 of walls 26 act like cantilever beams and are forced by the relatively high internal stress developed at the base of these free end portions to move back together as shown in Figures 5-11, thereby cutting 01f the tape or strip 8 and resealing the tube until further use.

in prior art closure caps, the closure member is generally in the nature of a simple beam secured at one end and fulcrumed between said end and the point of closure at a point relatively remote from the point of closure. However, in the present invention the closure member is a reed-like element which is in the nature of a cantilever beam due to the fact that it comprises the free end of a wall which is secured on each edge along most of its length. For any given outlet opening (i. e. for any given deflection from normal position) a cantiliver supported closure member such as reed-like element 30 will require a greater unit load applied thereto through application of pressure to the tube than will a rlosure member which operates as a fulcrumed simple beam similarly loaded at its overhanging end. The former will therefore develop a higher internal stress than the latter for any given opening, and this higher internal stress enables the cantilever supported reed-like free ends to cut off the extruded strip of cream or paste and effectively reseal the tube.

Low production costs is also an essential requisite in a device of this kind. The improved self-sealing closure cap 20 of Figures 5-11 is simple to make since it may be molded as a unit with side walls 26 having the required structural characteristics such as an enlarged root portion, convergence at their forward ends, etc. The only operations then required are the removal of a portion at 32 which results in a very narrow slit opening 33, and provision of slits 35. This enables inexpensive production of a self-sealing closure cap which is highly effective, thereby making commercial use of the cap feasible.

The closure cap of the embodiment of Figures 1-4 may be similarly produced at low cost.

In the embodiments illustrated in the drawings, both side walls are resilient and both have free ends formed by slits. While this is the most effective and preferred form, it is apparent that in its broader aspects, the present invention contemplates that only one of the side walls need be resilient and slit at its ends, and the other could be rigid and secured to the end members (14 and 25, respectively) throughout its entire length.

My invention may be used in dispensing any relatively soft paste or jelly and one very important use is the dispensing of salves and ointments. My cap or closure keeps the salve or ointment sterile and the thin relatively wide strip in which the salve may be extruded permits direct application without the need for spreading over an affected area.

The invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof and the present embodiment is therefore to be considered in all respects as illustrative and not restrictive. The scope of the invention is indicated by the. appended claims rather than by the foregoing description, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced .therein.

What is-claimed and desired to be secured by United States Letters Patent is:

l. A self-sealing closure for collapsible tubes comprising a body adapted to be secured to a collapsible tube and. having an opening through which the contents of the tube may pass, tworigid walls secured to said body on opposite sides of said opening, a third wall extending'between said two walls at one side of said opening, a fourth wall of resilient material extending between said two walls on the fourth side of said opening and engaging the third wall in abutting relationship at its end remote from said body at an acute angle, said walls forming a chamber about said opening, the fourth Wall having interior and exterior faces the entire surface of each of which lies in a single plane, said fourth wall being rigidly secured along its opposite edges to both of said two walls throughout a first portion thereof constituting. almost its entire length from said body outward toward its end and being of uniform thickness across any transverse section, the remainder of said fourth wall constituting the extreme outer end of said fourth fined in claim 1, in which the third wall is formed of resilient material, has opposed interior and exterior faces each of the entire surfaces of which lies within a single plane, is secured along its opposite edges over a first portion constituting almost its entire length from said body to said two walls, and is of uniform thickness across any transverse section, the remaining portion of said third wall constituting the extreme outer end of said third wall being cantilever supported by said first portion of said third wall and being free to move away from and toward said fourth wall by flexure of said third wall, the resilience of said third wall being such that the outer end of said third wall also moves away from said fourth wall to permit discharge of the contents of the collapsible tube when pressure is applied to the tube and returns to engagement with said fourth wall when such pressure is released.

3. An integrally molded self-sealing closure cap of plastic material having relatively high flexibility and strength characteristics comprising a body portion adapted to be secured to a collapsible tube and having an opening therein through which the tube contents may pass, a pair of relatively rigid end walls extending from said body portion in substantially parallel relationship on opposite sides of said opening, a pair of side walls extending from said body portion and secured at their edges to said end walls on opposite sides of said opening for a major portion of their length to form a chamber said side walls having a thickness progressively decreasing from their root section at said body portion to their forward ends, said side Walls converging to meet at their forward ends remote from said body in abutting relationship to form a very narrow slit, with the remaining forward portions of said side walls being unconnected to the end walls forming slits, said remaining forward portions constituting a pair of abutting resilient reedlike ends which are free to move toward and from each other, whereby the reed-like free ends of said side walls are cantilever supported so that when they are deflected from normal abutting position to form an outlet permitting discharge of the tube contents upon application of pressure to the tube, said reed-like ends act like cantilever beams and are forced by the relatively high internal stress developed at each of their bases to move back into abutting relationship at their forward ends thereby resealing the tube when such pressure is released.

4. A self sealing closure for collapsible tubes as defined in claim 1 wherein the said fourth wall is of uniformly decreasing thickness over its entire length between said body and the zone of juncture of said fourth wall with said third wall.

5. A self sealing closure for a collapsible tube comprising a converging nozzle of internal transverse quadrilateral cross section, the longitudinal cross section of said nozzle being in the form of an isosceles triangle with the apex thereof forming the zone of maximum convergence of the nozzle, the longitudinal cross section of said nozzle being formed by a pair of opposed walls fixed along their longitudinally extending edges to substantially uniformly spaced side walls over the major portion of their length from the divergent end of said nozzle and in juxtaposed contact therewith over the remainder of their length adjacent the zone of maximum convergence of said nozzle, said opposed walls each having interior and exterior faces the entire surface of each of which lies within a single plane, the extreme tips of the inner faces of said walls being in abutment to form such apex angle, said walls being formed of a flexible material such that, when pressure is applied to a collapsible tube associated therewith, the pressure will cause the flexible unconfined ends of said walls to separate to form a discharge orifice through which the contents of the tube is extruded, the resiliency of said opposed walls being such that, when the pressure exerted on the unconfined portions of said opposed walls as a result of compression of such a collapsible tube is relieved, the tips of said walls will return to their position of abutment to seal the opening and pinch off the stream of extruded tube contents.

6. A self sealing closure for collapsible tubes comprising a body structure having an opening through which the contents of a collapsible tube may be extruded, first and second rigid walls projecting from said body structure at opposite sides of and in substantially parallel relation to the axis of said opening, the inner faces of said first and second walls exposed to the contents of said tube converging from a maximum width adjacent said opening toward a point in substantial alignment with the axis of said opening, a third wall extending between said first and second walls and having an inner face exposed to the contents of such a tube inclined from a position adjacent the edge of said opening toward the axis of said opening at the point of minimum width of the inner faces of said first and second walls, and a flexible fourth wall extending between said first and second walls at the side of the axis of said opening opposite said third wall, the inner face thereof being inclined from a position adjacent said opening toward said third wall to a position in which the tip of its inner face abuts said third wall, said fourth wall being fixed along its side edges over the major portion of its length to provide a cantilever support for the remainder thereof adjacent said tip with said remainder being in juxtaposed contact along its side edges with the side walls so that the unconfined remaining end portion of said fourth wall can flex under pressure exerted by the contents of said tube when pressure is applied to said tube to separate its tip from said third wall and permit egress of the contents of the tube and upon release of pressure upon said tube to return to its position in abutment with said third wall and thereby pinch off the ribbon of extruded tooth contents and reclose said opening.

References Cited in the file of this patent UNITED STATES PATENTS 1,977,227 Berendt Oct. 16, 1934 1,992,067 Gunn Feb. 19, 1935 2,005,642 Thornton June 18, 1935 2,334,032 Rhodes Nov. 9, 1943 2,507,248 De Swart May 9, 1950 2,540,842 Stanley et al. Feb. 6, 1951 FOREIGN PATENTS 381,875 Great Britain Oct 13, 1932 50,839 Denmark Oct. 28, 1935

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