ONE WAY VALVE ASSEMBLY

BACKGROUND OF THE INVENTION

The present invention is directed to a one way valve assembly for

dispensing a sterile flowable substance while preventing any backflow of

contaminants into the source of the flowable substance. The valve assembly

includes a valve body enclosed by a pressure displaceable flexible member or

elastomeric member for effecting the passage of the flowable substance to a

controllable outlet while preventing any backflow to the source of the flowable

substance after dispensing individual portions of the flowable substance.

In the past, to maintain the flowable substance free of contaminants,

preservatives have been mixed in the flowable substance in the container from

which it is to be dispensed. The use of preservatives is an added expense and

tends to limit the effectiveness of the flowable substance, particularly when the

flowable substance is a pharmaceutical such as an eye care solution or it is a

food stuff.

Another consideration is the ability of the valve assembly to deliver a

selected amount to the outlet without causing any damage to the user, such as

when applying an eye care solution directly into the eye.

In recent years, flexible membranes have been used to control the flow of the

flowable substance to the valve assembly outlet while preventing any backflow

to the source of the flovrable substance, however, it has been difficult to provide

an effective procedure for manufacturing the valve assembly and limiting its

costs.

SUMMARY OF THE INVENTION

Therefore, the primary object of the present invention is to provide a

valve assembly for conveying a flowable substance from a closed source, such

as a collapsible container while preventing any backflow of contaminants

through the valve assembly into the source of the flowable substance after a

portion of the substance has been dispensed.

The collapsible container can be a bellows type, a tube, an internal bag or

other type of collapsible form designed to dispense practically all of its

contents. The container has a normally closed controllable outlet surface for

dispensing a flow of the flowable substance out of the valve assembly. The

container is in sealed contact with the valve assembly so that its contents do not

receive any contaminants when the flowable substance is dispensed.

Dispensation of the flowable substance is effected by applying pressure

to the container so that its contents flow to the valve assembly. The contents

may be a pharmaceutical, such as an eye care solution or other substance which

must be kept free of contaminants during dispensing a multiple number of

dispensed amounts. Other flowable substances can be food stuffs or beverages,

cosmetics, or other flowable substances intended to be maintained free of

contaminants during the dispensing operation. The container may be protected

by a housing so that pressure is not accidentally applied.

The valve assembly is an axially extending structure open to the

container of the flowable substance. The valve assembly is formed of an

axially extending inner core open to the container and formed of a rigid plastic

component. The interior of the core has a passageway for receiving the

flowable substance from the container. At least one port extending from the

passageway affords an opening for conveying the flowable substance out of the

inner core.

Tightly enclosing the inner core is an axially extending flexible

membrane covering the outlet end of the port through the inner core. The

flexible membrane moves outwardly from the inner core when the flowable

substance is pressurized and passes through the port and flows toward the outlet

end of flexible memDrane.

Laterally outwardly from the flexible membrane is a valve cover ending

in the controllable outlet orifice. The pressurized flowable substance travels

between the radially outwardly extended flexible membrane and the outer

surface of the inner core and flows to the controllable outlet orifice. The outlet

orifice can provide for a limited amount of the flowable substance to be

dispensed.

An over cap covers the exterior of the valve cover to protect the valve

assembly during storage, and to avoid accidental dispensing.

A collar joins the valve assembly to the container and affords a sealed

arrangement preventing any flow of contaminants into the container.

The various features of novelty which characterize the invention are

pointed out with particularity in the claims annexed to and forming a part of this

disclosure. For a better understanding of the invention, its operation,

advantages and specific objects attained by its use, reference should be had to

the accompanying drawings and descriptive matter in which there are illustrated

and described a preferred embodiment of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS:

Fig. 1 is an axial Iy extending view of a one way valve assembly

embodying the present invention;

Fig. 2 is an exploded view of the one way valve assembly shown in Fig

l;

Fig 3 a is an enlarged axially extending partial view of the one way valve

assembly in the at rest position;

Fig 3b is a partial view similar to Fig 3a, however, with the one way valve

assembly in the dispensing position; and

Fig 4 is an enlarged partial axially extending view of the dispensing end

of the one way valve assembly shown in Fig 3b.

DETAILED DESCRIPTION OF THE INVENTION

As shown in Fig, 1 the one way valve assembly 1 is composed of a

bellows container or source 2 holding a sterile flowable substance, a valve

assembly 3 for conveying the flowable substance from the container 2 to an

outlet when pressure is applied to the container 2 and an over cap 15 covering

the valve assembly 3 to prevent contamination from entering the valve

assembly 3 during storage.

The bellows container 2 collapses when pressure is applied to the

container, however, other containers may be used such as a tube or an internal

bag in a container which permit multi-dose dispensation of the flowable

substance without contamination entering the container following the

dispensing procedure.

The flowable substance may be a pharmaceutical, such as a eye care

solution, a food stuff, such as products or juices, and a cosmetic, such as a skin

care solution or toiletries, and liquid vitamins, all of which are intended to be

maintained free of contaminants from the ambient atmosphere.

The bellows container or source 2 is laterally enclosed by an axially

extending housing 6 to provide better ergonomic control during dispensing. A

slot 7 extending axially in the housing 6 permits a user to gain access to an

actuator 2a of the container as the flowable substance is pressed out.

A collar 8 connects the valve body 3 to the container 2 affording a scaled

connection so that ambient contaminants cannot pass into the container 2.

The valve assembly 3 has an axially extending inner core 10 bearing

against the opening of the container 2 so that flow from the container enters into

an axially extending blind passageway 11 in the inner core. The passageway 11

extends for a major portion of the axial length of the inner core. At

approximately half the length of the passageway 11 the inner core has at least

one port 12 extending transversely of the passageway axis from the surface of

the passageway to the outer surface of the inner core 10. The inner core 10 is

formed of a rigid plastic material and terminates inwardly of the outlet end of

the valve body.

A flexible membrane 13, such as an elastomeric member, is fitted tightly

over the outer surface of the inner core and extends from the opening in the

container 2 to the opposite end of the inner core 10. As can be noted in Figs. 2a

and 2b, the thickness of the membrane is variable along its axial length and in

the region of the outlet end of the inner core has an axially extending

continuous uninterrupted annular band considerably thicker than the remainder

of the flexible membrane 13, that is, the band is not separated in the axial

direction by axially extending cuts.

At its end adjacent the opening from the container, the flexible membrane

13 has an outwardly extending flange bearing against a flange on the inner core

is located at the opening from the container.

An axially extending valve cover 14 encircles the flexible membrane 13

and as shown in the rest position in Fig 2a is spaced radially outwardly from the

outer surface of the flexible membrane. The end of the valve cover 14 adjacent

the container 2 has a radially outwardly extending flange 14a bearing against

the flange at the end of the flexible membrane effecting the seal for the valve

body at the opening from the container 2.

The valve cover 14 is formed of an inner layer of an elastomeric material

extending axially from its flange 14a to and over the outlet end of the valve

body 3. The elastomeric material forms a soft cover 7 over the outlet end of the

increased thickness which is particularly advantageous when the valve

assembly is used for dispensing an eye care solution. Such a soft cover 7

prevents any damage to the eye.

The soft cover 7 has an outlet orifice 7a for dispensing the flowable

substance. The outlet orifice is closed in the rest position of the one way valve

assembly, however, when the flowable substance is being dispensed and exits

the outlet end of the flexible membrane, it flows radially inward to the outlet

orifice which then opens allowing the substance to flow out of the valve

assembly. When the flowable substance is dispensed and pressure on the

source is withdrawn the outlet orifice 7a closes blocking any backflow into the

valve assembly.

By selectively dimensioning the outlet orifice 7a a drop-like amount of

the flowable substance can be dispensed, for example if an eye care solution is

being dispensed. If a greater amount of the flowable substance is to be

dispensed the outlet orifice 7a can be formed for dispensing a larger quantity of

the flowable substance. The outer orifice 7a can be formed to provide a spray

or a stream of the flowable substance.

An over cap 15 is placed over the valve assembly when it is not in use

protecting it from contact with ambient contaminants and for unintended

dispensing.

When the flowable substance is to be dispensed, the over cap 15 is

removed and pressure is applied to the actuator 2a of the container so that an

amount of the flowable substance passes out of the container into the

passageway 11 in the inner core 10. The substance flows through the ports at

least one port 12 and expands the flexible membrane 13 radially outwardly and

flows toward the outlet end of the flexible membrane where it exits from the

flexible membrane radially inwardly into the outlet orifice 7a in the cover and is

dispensed.

By releasing the pressure on the actuator 2a of the container, the

dispensing operation is terminated and the flexible membrane 13 returns

inwardly into contact with the outer surface of the inner core 10. The inward

movement of the flexible membrane start at its outlet end because of its

increased thickness and affords gradual contact with the outer surface of the

inner core returning any flowable substance through the ports back into the

container whereby contaminants cannot enter the container.

Dispensing individual portions of the flowable substance can be

continued until the container is almost completely emptied.

As mentioned, a variety of pharmaceuticals, cosmetics, food stuffs and

other flowable materials can be dispensed where it is important to maintain

them free of contaminants from the ambient atmosphere. The flowable

characteristics of the material being dispensed determines the type and

dimension of the valve body.

The material forming the outlet orifice 7a does not absorb the flowable

substance, any substance entering the outlet orifice is ejected and does not

return into the space between the inner core and the flexible membrane.