US 1989714 A
Description (OCR text may contain errors)
Feb. 5, 1935.
N. sTATHAM SELF SEALING VALVE Filed Sept. 25, 1930 w d fw Patented Feb. 5, 1935 UNITED STATES PATENT OFFICE 8 claims.
This invention relates to a self-sealing valve and more particularly to an automatic closure for collapsible tubes, s uch asare commonly used as containers for dental cream, shaving soap,
library paste, glue, etc.
sired result Without increasing the cost of the tube to a prohibitive iigure. y
It is an object of my invention to provide a valve which may be applied to or constructed in the outlet of a collapsible tube and which will permit the extrusion of the contents of the tube when a pressure is applied upon the surface of the tube but which will automatically arrest the i flow of material through the outlet upon the release of the pressure upon the tube; Another object of the invention is to provide means for increasing the pressure required to open a valve of this type. A further object is to provide a self-operating valve which may be economically constructed and applied to a collapsible tube. It is also an object to provide means for preventing extrusion of the material from the tube upon the accidental application of pressure to the container. Other objects will become apparent. The invention, in general, comprises the use of a diaphragm of rubber or other exible material across the outlet of the container, which diaphragm contains a `slit or other opening which is normally closed, but which may be opened by a pressure upon the contents of the container, to permit the extrusion' of material from the container through the slit, the diaphragm having sufficient resilience to arrest the ilow of material from the container when the pressure is released. In describing the invention reference will be made to the dra in which Figure l illustrates a fractional vertical section through the center of the upper portion of a collapsible tube embodying my invention. Figure 2 is a top plan View of the tube shown in Figure l. Figure 3 is a sectional view similar to Figure l, illustrating a cap which may be applied to my improved closure. Figure 4 is a side elevation and Figure 5 isa plan view of the cap shown in Figure 3. Figure 6 is a fractional vertical section through the center oi a tube utilizing a modification of my invention and Figure 1 is a fractional top plan view of the tube shown in Figure 6. Figure 8 is a View similar to Figure 3 illustrating a modied form of the invention.
In the several figures, the numeral 1 denotes a collapsible tube of the type customarily used as a container for dental paste, shaving soap, glue, 5 etc. The rubber diaphragm 2 is inserted Within the neck 3 of the collapsible tube and is retained there by a shoulder 4, formed in the. neck of the tube, and a washer 5. The washer 5 may be of such dimensions as to fit tightly within the neck 10 3 and may be forced into it under pressure before lling the tube. At the center of the rubber diaphragm 2, a slit 6 extends through the rubber at substantially right angles to the normal surface of the diaphragm.
In using a collapsible tube embodying my improved closure, the tube is iilled in the usual manner and a pressure is applied to the lower portion of the tube as is customary in extruding pastes and heavy liquids from collapsible tubes. 20 The pressure of the contents of the tube against the yrubber diaphragm 2 forces it outwardly and opens the slit 6 so that a strip of paste will be extruded from the tube. Upon release of the pressure applied to the tube the resilience of the 25 diaphragm will return it to its normal position and thereby close the slit and prevent the further extrusion of the contents of the tube. If the tube is used for dental paste, shaving soap, etc., any slight excess remaining upon the exterior of the 30 valve after releasing the pressure may be removed by inserting the valve in a stream of water, since the closed valve will prevent the water from contacting with the contents of the tube.
For ordinary use the rubber diaphragm would 35 be sumcient to retain the paste within the tube. However, in transporting or packing the tube, where it is likely to be subjected to accidental pressures, it may be advisable to apply an additional closure to prevent unintentional extrusion 40 of the contents. This may .be accomplished by simply afxing a disc of metal or other rigid material to the outer surface of the shoulder 4 by means of a suitable adhesive. Such a disc could be applied to the tube at the time it is nlled in -45 order that extrusion may be prevented before it is intended to initially use the tube.
If it is preferred to use a replaceable covering for this purpose, a cap similar to that shown in Figures 3 and 8 may be supplied with the tube. 50 This cap 'l may be of any suitable material and may have an edge of resilient material which is turned down to form the rim 8. A series of notches 9, 9 are positioned around the rim 8 to give greater flexibility and to permit the cap to 55 expand about the neck of the tube. These notches preferably extend to beyond the bend to give the desired degree of iiexibility. If desired, a bead or ,depression may be made in the neck of the tube with a corresponding depression or bead on the inner surface of the edge of the cap to assist in retaining the cap. The top of the cap may also have a depressed portion 9a which is shaped to contact with the diaphragm 2 to retain it in its normal position with the slit 6 closed. This cap may also have a handle 10 for use in applying and removing it.
It is apparent that many other shapes and designs of closures may be substituted for the cap?, which is shown as' illustrative of such closures. 'Ihe cap may also be applied to modifications of my self-sealing valve, such as thatabout to be described.
In Figures 6 and 'l I have shown a modified form of my invention in which the diaphragm 2a is applied across the outer edges of the neck 3a of the tube. A cap 11 is then applied to the end of the tube 'and is fastened permanently to the neck 3a 'by means of a bead 12 in the cap 11 which is retained within a groove 13 in the neck 3a, or by any other suitable means. At the center of the cap 11 there is an opening 14 which may be circular, rectangular or of any other desired shape. This opening is so positioned as to be opposite the slit 6a in the rubber diaphragm 2a,
in order to permit the extrusion of material from the tube.
The cap 11 is so shaped as to provide a slightly convex inner surface which is adapted to slightly depress the diaphragm 2a. By so depressing the diaphragm 2a the slit 6a is pressed together at its outer edge and a greater pressure is required to expand the diaphragm sufficiently to permit the extrusion of the contents of the tube through the slit. Such an arrangement may be preferred with a tube having a large opening or Where a less resilient material is used.
For use in tubes of dental paste and shaving soap, I prefer to use a diaphragm of pure rubber which has been vulcanized in the usual manner, using sulphur as the vulcanizing agent. It is not intended, however, to limit the diaphragm to this particular material, since it is apparent that under different circumstances of use it may be desirable to use different materials. For example, it may be preferred to use a metal valve comprising ,two thin resilient plates which slightly overlap and which may be expanded against the resilience of the metal to provide an opening for the extrusion of the material from the tube. Other resilient materials may be used for this purpose but the material chosen should, of course, be one which Willnot have any harmful reaction upon the contents of the tube.
I have found it convenient to use a rubber dia' phragm having a thickness of about .030 (thirty thousandths) of an inch but this thickness may be varied to suit the particular requirements and the material used. The orice in the diaphragm may be a slit of such a length as to give the desired width to the strip of extruded material or the opening may be in some other suitable shape which will retain the material within the tube until a pressure is applied to it and will then give the -desired configuration to the extruded material. For example, a short cross slit crossing the slit 6 or 6a may be made in the diaphragm. Such a form may particularly be applicable to a tube having a small neck.
'I'he slight depression of the diaphragm as i1- lustrated in` Figure 6 may, of course, be used in the modiiication illustrated in Figure 1 by suitably shaping the shoulder 4 as illustrated in Figure 8. In this case the washer 5a will retain the diaphragm 2a tightly against the shoulder 4a, so that the diaphragm is held in a slightly depressed position, as illustrated in this figure. This depression may be increased or reduced to obtain the desired flexibility in the diaphragm for the particular use to which the closure is to be applied.
It is apparent that many modifications of the invention may be used and the particular forms illustrated are not intended as limitations of the inventions defined in the following claims.
What I claim is:
1. A self-sealing valve comprising a diaphragm yof resilient material, means for normally retaining Asaid diaphragm across the outlet of a container in such a position that the outer surface of the diaphragm is slightly concave, said diaphragm having an orifice which is normally closed but which may be opened when applying pressure to the contents of the tube.
2. A self-sealing valve comprising a diaphragm of resilient material retained across the outlet of a container, said diaphragm having an orifice which is normally closed but which may be opened when applying pressure to the contents' of the tube, and means to retain said diaphragm in juxtaposition to the end of the tube compriss ing a cap member having shoulders extending inwardly from the sides of the tube and adapted to maintain the diaphragm in such a position that the outer surface is concave, said cap having an opening aligned with said orice.
3. A self-sealing valve for collapsible tubes comprising a seat formed in the neck of the tube by the metal of the tube bent inwardly, a resilient diaphragm having an aperture therein and having a diameter substantially equal to that of the interior of the neck of the tube, a washer having an outside diameter sufficiently large to t tightly within the neck of the tube, said washer being forced into the neck of the tube to retain the diaphragm against the inner surface of the seat.
4. I'he combination with a valve as defined in c1aim'3 of a removable cap, having a depressed portion adapted to` bear upon and prevent outward movement of the diaphragm.
5. A self-sealing valve comprising a diaphragm of resilient material, a container having an annular surface slanting inwardly and adapted to receive said diaphragm, and means for normally retaining saidvdiaphragm across the said outlet in such a position that the outer surface of the diaphragm is slightly concave, said diaphragm having an orifice which is normally closed but which may be opened by applying pressure to the contents of the tube.
6. A self-sealing valve for collapsible tubes comprising a diaphragm of resilient material, means for normally retaining said diaphragm across the outlet of a container in such a position that the outer surface is slightly concave. said diaphragm having an orifice which is normally closed but which may be opened by applying pressure to the contents of the tube, and a washer having an outside diameter sumciently large to t tightly within the neck of the tube, said washer being forced into the neck of the tube to retain the diaphragm against the inner surface of the first mentioned retaining means.
7. The combination with a valve as defined in claim 1 of a removable cap having a depressed portion adapted to bear upon and prevent outward movement o! the diaphragm.
8. The combination with a self-sealing valve for a collapsible tube, comprising a diaphragm of 5 resilient material extending across the outlet of the tube and having an orice which is normally closed but which may be opened by a pressure applied upon the contents of the tube, of a. removable cap having a depressed portion adapted to bear upon and prevent outward movement of the diaphragm.
, NOEL STATHAM.