GB2096245A - A dispensing device for pastes, creams and thick liquids - Google Patents

Abstract

The dispensing device is provided with a delivery valve V through which soft or pasty products can be delivered. The device comprises a substantially cylindrical body 1 in which a piston 3 is disposed, on one side of which the product and delivery valve V are disposed, and on the other side of which there is a charge of propelling gas. At the end of the delivery stroke the residual pressure on the opposite side of the piston to the valve member is exhausted by the action of the low part of the valve member 11 engaging a recess 3E in the piston, which acts to move the piston laterally thus breaking its seal with the body 1. <IMAGE>

Description

SPECIFICATION A dispensing device for pastes, creams and thick liquids This invention relates to a dispensing device for soft or pasty products or thick liquids, such as cosmetic creams and alimentary products, tooth pastes, mustards, mayonnaise and the like.

Known are dispensing devices designed for the use above referred to, such devices comprising a metal container, in which a movable plunger is mounted and provided at one end with a dispensing valve and at the other end with a valve or plug, through which the propellant (such as liquefied gas) is introduced or charged which through the plunger exerts a pressure on the product that is delivered when the delivery valve is opened. In another type of device, a flexible bag is used instead of the plunger.

Even with relatively moderate thickness, such metal containers are capable of assuring that the residual propellant (that is to say, the propellant that remains after delivery of the whole product) does not give rise to any explosion. While being expensive and heavy, such metal containers have not been hitherto replaced by plastics container as the latter could explode.

Now, the present invention is directed to provide a dispensing device enabling to release the pressure upon completion of the product delivery and accordingly to avoid dangers that could arise in the presence of an internal pressure.

According to the invention, a dispensing device comprising an internally cylindrical body, a plunger movable- in said body, and a delivery valve, is essentially characterized in that the plunger has a resilient transverse capability of displacement, which plunger is provided with engagement means with which counter-means of the delivery valve can be engaged, such a valve being of inclinable or tiltable type, so that when inclined or tilted the valve will cause a transverse displacement of the plunger and, as a result, the generation of a passage between said body and plunger enabling the propellant to move beyond the plunger and exhaust to the atmosphere through the valve.

Inclinable or tiltable type of valves, also referred to as flexible valves, are known and comprise a stem having an axial blind hole at one end communicating with radial openings. This stem has a head at one end and a flange spaced apart from the latter.

At its portion between said flange and head, the stem is arranged within the hole of an elastically deformable element sealing against the flange and head. By laterally bending or inclining the stem, the radial openings are communicated with the product volume or chamber. When the stem is released, the resiliency of the member moves said stem back to rest or inoperative position, where such a communication is shut off.

In a particular embodiment of the invention, the head on the stem forms the counter-means pertaining to the valve, whereas the engagement means comprise a set in the plunger, into which said head penetrates.

The invention will be more clearly understood from the following detailed description given by mere way of unrestrictive example of a preferred embodiment thereof as shown in the accompanying drawings, in which: Fig. 1 is an axial sectional view showing the device according to the invention at rest or inoperative position and practically full of product; Fig. 2 is a view on enlarged scale showing the end of the device having the delivery valve mounted thereon, which valve is shown at bent or inclined attitude at delivery step; and Fig. 3 is a view showing the same end prior to propellant charging.

Referring to the figures of the accompanying drawings, reference numeral 1 designates a cylindrical body made of plastics or other material.

in case also metal, which at one end is closed by a bottom integrally made therewith and open at the other end, where it is peripherally provided with an annular enlargement 2. At the other end this body 1 is closed by a cover or cap 4 which is snap applied and provided to this end with a collar edge 5 engaging below said annular enlargement 2.

At its central portion, the cover or cap 4 is provided with an inclinable or flexible delivery valve "V". This valve comprises a substantially cylindrical stem 6 made of metal or plastics and provided with an axial blind hole, and at one end with a series of radial openings 7. The stem also has a disc-like head 11, and spaced apart therefrom an annular flange 12 having conical configuration on one side. The valve also comprises a deformable resilient element, made of rubber or elastomer and designated at 8, which has a central tube or sleeve 8A, in which said stem 6 is disposed and the ends 8B and 8C of which resiliently abut for sealing purpose respectively against said flange 12 and head 11 at rest or inoperative position.The element 8 comprises a diec-like portion 8D, extending throughout the inner face of said cover or cap 4, so as to act as a seal between said cylindrical body 1 and cover or cap 4. Said element 8 is retained by cover or cap 4 through a central annular rim 4a of the latter entering an annular seat 8E on said tube or sleeve 8A.

A hollow member 9, made of flexible material, such as plastics, is slipped on said stem 6 and at its very thin spherical end portion has a slit 1 0. Under rest or inoperative conditions, the slit is closed (see Figs. 1 and 3), in that its two edges adhere against each other, but when the product is being delivered (Fig. 2) the slit edges move away under the thrust exerted by the product.

A plunger 3 made of flexible synthetic material is slidably mounted in the cylindrical body 1 and comprises a peripheral skirt 3A of arcuate crosssection, or having outwardly projecting edges 3B and 3C at the ends. The plunger also comprises a transverse central portion 3D, where a seat or cylindrical blind hole 3E is provided, which seat or hole is of a diameter which is about the same as said head 11 , the latter being designed to enter therein as facilitated by the flaring 3F ahead of the seat 3E.

A metered amount of subcooled liquid propellant is introduced into said body 1, open as shown in Fig. 3. The body 1 is then immediately closed by means of the above mentioned cover or cap 4, provided with valve and to which the plunger 3 is temporarily joined (because a slight shrinking or swell exists between said head 11 of stem 6 and seat 3E of the plunger). Then, the product is charged under pressure into the device through the stem 6 (after removal of the member or sheath 9). The charging pressure causes the resilient squashing of the above mentioned tube or sleeve 8A, so that the radial openings 7 will communicate with the interior of body 1. Of course, the charging pressure exceeds the propellant pressure and accordingly the product enters and displaces the plunger 3 until the latter reaches the bottom of body 1.The condensed propellant is then in the chamber or space between said bottom and plunger 3, the central portion 3D of which is spaced apart from the lower contour of the sealing skirt 3A.

During use, by lateraily pressing the member or sheath 9 and accordingly inclining the stem 6 (see Fig. 2), the head 11 moves for some length (see A) away from the inner edge 8C of the resilient sealing element 8, whereby the radial openings 7 are communicated with the contained product.

The propellant urges the plunger 3 and the product is expelled outside of the widened out slit 10.

At some time, the product having been depleted, the seat 3E is on the head 11 and by further acting upon said member or sheath 9 (that is inclining the latter, so that also said stem 6 is inclined) the plunger 3 is transversely displaced (which is allowed by the elastic deformability of the sealing skirt 3A), so that the propellant behind the plunger can step over the latter and exhaust to atmosphere through said valve V and member or sheath 9. At the end of use, the container is brought to atmospheric pressure.

Of course, said cylindrical body 1 could be also of metal, since even in this case the absence of pressure constitutes a sure safety factor. The cover or cap 4 may be of metal and by screwing may be fitted to said body 1.

Claims (8)

1. A dispensing device for pastes, creams and thick liquids, comprising an internally cylindrical body, a plunger movable in said body, and a delivery valve, wherein said plunger has a transverse elastic capability of displacement, which plunger is provided with engagement means, with which counter-means of the inclinable or tiltable delivery valve are engageable, so as to cause when inclined a transverse displacement of the plunger and resulting generation of a passage between said body and plunger, enabling the propellant to step over the plunger and exhaust to atmosphere through said valve.

2. A device according to Claim 1 , wherein said plunger has a sealing skirt provided with resilient end edges.

3. A device according to Claim 2, wherein said plunger comprises a central disc-loke portion peripherally joined to said skirt.

4. A device according to Claim 1, wherein said engagement means of the plunger comprise a seat, where a head can enter, which head is provided on the stem of said valve and forms the engagement counter-means.

5. A device according to Claim 1, wherein said stem is hollow with transverse openings, supported by a resilient sealing element.

6. A device according to Claim 5, wherein said resilient element is carried by a cover or cap connectable with the body and acting as a seal or gasket between the body and cover or cap.

7. A device according to Claim 6, wherein said body is provided with an integral bottom wall.

8. A dispensing device for pastes, creams and thick liquids, substantially as hereinbefore described with reference to the accompanying drawings.