TITLE OF THE INVENTION:
IMPROVEMENT IN SELF-CLOSING CLOSURES
TECHNICAL FIELD :
Thi s invention refers to an improvement in such self-closing closu res which include two menbers provided to be connected to each other along out er peripheral portions thereof , one of said meirbers having a diaphragm provided with a central outlet opening and the other one having a stem which in the closed position of the closure sealingly closes said outlet opening but by a deformation of the diaphragm caused by a pressure exerted upon the material to be di scharged can uncover said outl et opening .
Self-closing closures of the kind referred to have proven to be very useful especially as closures for tubes.
In some cases it i s however desi rabl e to attain a suction of ai r into the container to which the closure i s applied and as a suction of air does not take place in these known closures it has been a demand to easily provide a closure having such a possibil ity.
KNCTON IN THE ART :
Known in the art i s an arrangement with a hollow stem and a valve means to cover respectively uncover the opening thus obtained in the stem but such an embodiment i s -especially when it i s about closures of small dimensions- not completely safe since the opening may be unintentionally blocked by particles , for instance f rom the di scharged iraterial .
Al so in other respect s the known st ructure has drawbacks such that i t can only be used to a l imited extent .
DESCRIPTION OF THE INVENTION :
The main obj ect of the invention has been to provide a simple and reliable device of the kind referred to.
A further object has been to provide a simple arrangement for locking the closure by transport and so forth such that an unintenticnal discharge of material cannot occur from the tube or the like to which the closure is connected.
To obtain these and still further obj ects the invention has the characteri stics appearing from the claims.
EXPLANATION OF THE DRAWING:
The drawing illustrates an exaπplifying errbodiment of the invention and the sole figure shows a transverse section through a closure according to the invention and connected to a tube.
DETAILED DEXRIPTION OF THE PREFERRED EMBODIMENT :
The closure as shown includes a first closure meirber generally designated as 1. This menber has an outer, annular portion 2 from which extends an annular sealing lip 3, which as appears from the drawing- i s conical and extends downwardly from the portion 2. Extending upwardly from said annular portion 2 i s a likewi se annular flange 4. The annular portion 2 continues via an annular wall portion 5 in an attachment portion 6 which i s tubular and in the inner surface thereof has a profiled groove 7 and a serrated port ion 8 for a purpose to be described. The attachm-ent portion 6 i s by means of a nuπber of ribs 9 connected to a stem 10, which in the upper end thereof has a cylindrical portion 11 , provided to sealingly cooperate with the outlet opening of the diaphragm member of the closure. The wall portion 5, which connects the outer portion 2 with the attachment portion 6 has an air inlet opening 12.
The closure now described i s intended to be connected to a tube generally designated as 14. This tube, like the closure itself , is preferably made from a plastics material and has deformable walls. The conical opening of the tube has an annular, outwardly directed bead 15 and has thereabove a serrated portion 16. The bead i s
portion 16 cooperates with the portion 8 in order to prevent the closure meπber 1 from being rotated in relation to the tube. The conical opening of the tube and/or the closure member 1 i s made f rom a material with elastically yieldable characteri stics such that the closure merrber in a manner known per se may be snapped to the opening of the tube.
Reference numeral 17 denotes a second closure merrber which has an annular outer portion 18 having an annular profiled groove 19 in the inner surface thereof . Thi s groove is so shaped that the seal ing l ip of the closure member 1 may be received in the groove without risk for the closure menbers 1 and 17 to unintentionally be separated from each other. For this purpose the seal ing lip as mentioned i s conical and the groove 19 preferably ends in a surface perpendicular to the l ength direction of the closure. Also the closure members 1 and 17 are thus snapped together.
Extending from the annular outer portion as a thin-walled portion 20 serving as a diaphragm and thi s diaphragm according to the drawing. i s inclined downwards towards the centre of the closure when the closure i s in the closed position thereof .
The diaphragm 20 continues in an oppositely directed conical porti on 21 having an otlet opening 22 provided to cooperate with the end portion 11 of the stem 10.
As appears from the drawing the lower end surface of the portion 18 is situated at a di stance from the coni cal opening of the tube 14 such that an annular space i s generated between the outer and l ower portion of the closure and the coni cal opening of the tube.
A valve meπber, generally designated as 23 and preferably made f rom a plast ics mat erial with rubber-l ike properties includes a cyl indrical , elongated shaf t member 24 which in the upper end thereof continues in a funnel-shaped or bowl-shaped portion 25 whi ch has an upwardly successively dimini shing wall thickness such that the upper edge of the funnel wil l constitut e an annular seal ing l ip. Intermediate its ends the shaft portion has a pair of annular beads 26 located at a certain di stance from each other.
The valve member now described forms together with the air inlet opening 12 a check valve and for thi s purpose the funnel-shaped portion 25 of the valve meπber is inserted in the opening 12 and is axially fixed. The latter fact is obtained in that the lower end of the shaft from above is pressed into an opening of substantially the same diameter as the shaft portion and provided in a proj ection 27 extending from the portion 6. The opening in this proj ection has a diameter less than the beads 26 but owing to the fact that the valve meπber is made from a rubber-like, elastically compressible material the lower bead (which preferably has less diameter than the lower one) is compressed to such an extent that it can be forced through the opening 27 when the valve member from above is pressed down towards the proj ection. Wien the lower bead has passed the lower surface of the proj ection it of course expands back to its original shape and together with the upper bead, which then is provided to rest against the upper surface of the proj ection, the bead will hold the valve meπber axially fixed. The valve meπber is as mentioned made from a rubber-like material and the funnel-shaped portion thereof snugly fits in the opening 12.
The closure now described works in the following manner:
In the ini tial position the members take the positions as shown in the drawing. When the tube with the closure in this condition is somewhat squeezed the pressure upon the material contained in the tube will increase and as a consequence thereof the diaphragm 20 will be bent upwardly to a substantially planar position and then to a convex shape thus altering from the concave shape it had in the initial position. It is obvious that the outlet opening 22 will then be uncovered and that material will be expelled through the opening in question.
When the pressure upon the tube content ceases the diaphragm retakes by means of its own resiliency the initial shape which causes the stem to again cover the opening 22. No further di scharge of material takes place.
When the outlet opening is covered by the stem 10, 11 there is generated an under pressure in the closure as compared to the surrounding atmospheric pressure. The atmospheric pressure will thus force the
funnel shaped portion of the valve member to be deformed such that air i s sucked into the closure (and to the tube) until an equil ibrium occurs . Owing to the fact that air is sucked in according to the arrow, i . e. through the annular space between the closure and the conical opening of the tube the risk for blocking or clogging is practically eliminated and as the hole 12 may be adapted as regards nuπber and dimension to the actual need it is possible to pre-calcu late the time which i s required for the supply of air. Mien the inside and outside pressures are the same the funnel-shaped portion of the valve member of course returns to its initial shape and keeps the opening 12 covered.
It is obvious that a controlled air intake as a compensation for the amount of material expelled at any occasion is achieved.
It i s often desired that a closure be designed so as to be locked against unintentional opening. For thi s purpose there extends from the diaphragm portion , preferably from the t ransition between the diaphragm itself and the portion 21 a number of proj ections 28 directed towards the interior of the closure and having hook-shaped catches 29. Said catches 29 are so positioned in relation to the ribs that they in a certain angular position of the two closure menbers relative to each other may grasp the lower edge of the ribs and thus prevent the diaphragm from leaving its ini tial , closed position . By turning the closure member 17 relative to the closure member 1 from said angular position an angle less than the angular di stance between the ribs 9 the closure i s of course brought to an active position , i . e. a position in which discharge of material can take place by squeezing the tube more or less . Thi s active position thus corresponds to the init ial position described in connection wi th the description of the function . In order to lock the closure for transport it i s thus only necessary to turn the closure member 17 to such an extent that the hook shaped catches thereof catch the ribs.
It i s obvious that the closure member has to be f ixed against rotat ion relative to the tube 14 to obtain a locking action of thi s kind and thi s i s achieved by means of cooperation between the serrations 8 and 16.
INDUSTRIAL APPLICATION:
The closure i s suitable for connection to tubes and similar containers the content of which is intended to be exerted to a pressure, preferably a manual pressure.