Push up dispenser with capsule valve

A push up fluid dispenser having a fluid storage container and a vertically oriented plunger carried in the container, with the plunger being manually pushable upward for dispensing fluid from the container. The container includes a valve cylinder mounted in the container and having an upper opening and an interior passage for slidingly receiving the plunger, and the plunger having a fluid flow passage therein providing a flow path from the cylinder interior to the exterior of the dispenser. A first one-way valve is disposed for control of fluid flow into the cylinder interior through an upper opening and a second one-way valve is disposed for control of fluid flow from the cylinder interior into the plunger passage, with a spring between the cylinder and plunger urging the plunger downward.

BACKGROUND OF THE INVENTION 
This invention relates to fluid dispensers, and in particular to a new and 
improved push-up type dispenser. 
Push-up dispensers are widely used for dispensing a variety of materials, 
both powders and liquids, typically lotions and soaps. Push-up type 
dispensers are very desirable, permitting operation by engaging a plunger 
with the palm of the hand and retention of the dispensed material in the 
same hand. 
The push-up dispensers presently known are gravity or free flow devices, 
with upward motion of a plunger opening a flow path from the interior of 
the material container, downward around the plunger to the exterior of the 
dispenser. Dispensers of this type have problems with leaking or dripping 
of material and with irregular flow of material. One solution for reducing 
leaking is to use a spring providing a stronger closing force, however 
this is an undesirable solution as it also increases the force required 
for actuating the dispenser. 
Accordingly it is an object of the present invention to provide a new and 
improved push-up fluid dispenser which overcomes the leaking and dripping 
problem. A further object is to provide such a fluid dispenser which 
incorporates a positive displacement pump that can dispense a metered 
amount of fluid. A particular object is to provide such a dispenser 
incorporating a head holding capsule or one-way valve at or near the top 
of the dispenser valve chamber for achieving the non-drip operation. 
It is another object of the invention to provide a push-up fluid dispenser 
which has a relatively low operating force while at the same time having a 
relatively high compression ratio. An additional object is to provide such 
a dispenser which can generate a suction for drawing liquid into the valve 
chamber during the return stroke. 
It is another object of the invention to provide a push-up fluid dispenser 
with a manually operated plunger which plunger has an outlet fluid flow 
path therethrough with an outlet opening positioned above the lower end of 
the plunger, so that the dispenser fluid outlet remains a constant 
distance above the operators hand during the upward or dispensing stroke. 
A further object is to utilize this construction with a positive 
displacement pump so that the fluid is ejected through the outlet opening 
into the operators hand away from the plunger end. 
These and other objects, advantages, features and results will more fully 
appear in the course of the following description 
SUMMARY OF THE INVENTION 
A push-up fluid dispenser having a fluid storage container and a vertically 
oriented valve mounted in the container, with the valve plunger being 
manually pushable upward for displacing fluid from the container. The 
dispenser includes a valve cylinder mounted in the container with the 
plunger slidably mounted within the cylinder and with the plunger having a 
fluid flow passage therein providing a flow path from the interior of the 
cylinder to the exterior of the dispenser. Two one-way valves are provided 
with one controlling fluid flow into the chamber through an upper opening 
of the chamber and with the other providing for fluid flow from the 
chamber into the plunger passage. In the preferred embodiment, a 
compression spring holds the two one-way valves in position and urges the 
plunger downward for the return or vacuum stroke. The plunger is moved 
upward against the spring in the compression or dispensing stroke, 
ejecting a predetermined amount of fluid from the valve cylinder. 
A self-contained head holding capsule valve for use as a one way valve for 
controlling the flow into the dispenser container.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
In the drawing figures, a dispenser 10 includes a container 11 having a 
shoulder 12 resting in a cup-shaped section 13 of a wall mounting bracket 
14. The container has a neck with a first threaded section 15 positioned 
in an opening 16 of the mounting bracket, and is held in place on the 
mounting bracket by a mounting sleeve 17 having internal threads which 
mate with the threaded section 15 of the container. This arrangement for 
mounting the container in the mounting bracket is conventional. 
The valve includes a valve cylinder 20 formed with an annular groove 21 
having internal threads which mate with another threaded section 23 of the 
container neck for mounting the valve cylinder at the open end of the 
container, with a seal gasket 24 at the open end of the container An air 
inlet opening is provided at the upper end of the container and in the 
embodiment of FIG. 1, a one-way check valve 26 is mounted in the opening 
by a spring washer 27 and seal gasket 28 The check valve 26 comprises a 
molded body 29 with a flexible duckbill valve 30 positioned therein. The 
sides of the duckbill are normally closed as shown in FIG. 1, and are 
opened when the exterior pressure exceeds the interior pressure of the 
container, permitting flow into the container. Conversely, when pouring in 
liquid, the pressure within the container exceeds the pressure outside the 
container, and the sides of the duckbill are compressed together, 
providing the desired sealing. This configuration prevents leakage from 
the container when it is inverted for filling, while permitting flow of 
air into the container to equalize the internal and external pressures 
during dispensing. Other types of one way valves may be used, such as a 
ball and spring check valve, if desired. 
A plunger 32 is mounted within the valve cylinder 20, with a one-way valve 
33 adjacent an upper opening 34 in the valve cylinder, and another one-way 
valve 35 carried at the upper end of the plunger 32. A spring 36 is 
positioned between the valves 33, 35 with a washer 37 at the upper end of 
the spring and another washer 38 at the lower end of the spring. An 
annular seal 39 is carried in an annular groove in the plunger The plunger 
with the valves, spring and seal are held in place by a pin 42 in the 
valve chamber, with the inner end of the pin riding in a slot 43 of the 
plunger. 
The plunger has an internal fluid flow path including an axial section 45 
and an oblique section 46, with the outlet end 47 of the oblique section 
positioned above the lower end 48 of the plunger. 
The preferred embodiment of the one-way valve 33 is a self-contained head 
holding valve, as best seen in FIGS. 2 and 4. A washer 51 is enclosed in a 
resilient seal 52. The washer 51 has a central opening with an annular 
shoulder 54. The seal is molded of a flexible resilient material with an 
annular rim 55 having a groove for receiving the washer, and a central 
flapper 56 joined to the rim by a plurality of spokes 57. This design is 
sometimes known as a capsule valve. In assembling the valve, the rim 55 of 
the seal is stretched over the edge of the washer, bringing the flapper 56 
into engagement with the annular shoulder 54. In this arrangement the 
valve is normally closed, with the flapper blocking flow through the 
opening in the washer. A pressure differential across the valve with a 
higher pressure above moves the flapper away from the washer, permitting 
flow through the valve. The stretched condition of the seal when installed 
on the washer urges the flapper against the shoulder so that the valve is 
pre-loaded in the closed position. The pressure differential required to 
open the valve and permit flow therethrough preferably is two to four 
times the pressure of the head of the liquid in the container. 
The lower one-way valve 35 typically is a duckbill valve of the same design 
used in the valve 26 shown in FIG. 1 at the top of the container. 
An alternative construction for the valve 26 is shown in FIG. 3, with a 
duckbill valve 59 held in the container 11 by a bracket 60 which is 
attached to the container in a leak proof manner, such as by an adhesive 
or cold welding or otherwise as desired. Preferably, the valve 59 is an 
interference fit in the bracket 60. The interior of the duckbill valve 59 
is aligned with an opening 61 in the container, and operates in the same 
manner as the valve 26 of FIG. 1. The opening 61 may be in the top of the 
container or in a side of the container near the top. 
In operation, the container 11 is removed from the support bracket 14 by 
unscrewing the sleeve 17. The container is then inverted and the cylinder 
20 is removed by unscrewing. The container is filled with the fluid to be 
dispensed, typically a soap or lotion, the cylinder 20 is screwed in 
place, the container is turned over to its normal position, inserted into 
the bracket 14 and fastened in place by the sleeve. The check valve 26 at 
the upper end of the container prevents leaking during the filling 
operation. The dispenser is now in the position of FIG. 1. 
Fluid is dispensed by pushing upward on the plunger 32. The dispenser 
operates as a positive displacement pump and the chamber within the valve 
cylinder between the valves 33, 35 ordinarily initially is empty, 
requiring one or more priming strokes. Once the chamber is filled with the 
fluid, normal operation is achieved. 
An upward motion of the plunger from the position of FIG. 1 to the position 
of FIG. 2 compresses the fluid in the chamber, forcing the valve 35 to 
open as shown in FIG. 2, and expels the fluid from the chamber through the 
flow path of the plunger and out through the outlet opening 47. Normally, 
the plunger is pushed upward by placing the palm of the hand at the 
plunger lower end 48, and the fluid is ejected into the operators palm. As 
illustrated in FIG. 2, upward motion of the plunger is limited by full 
compression of the spring. Alternatively upward motion can be limited by 
engagement of the plunger with the valve chamber at 50. Having the flow 
path through the plunger with the oblique exit, keeps the fluid away from 
the lower end of the plunger, while at the same time the dispenser is 
easily operated with one hand. 
Next, the operator releases the plunger, typically by lowering the hand, 
and the spring 36 moves the plunger down from the position of FIG. 2 to 
the position of FIG. 1. When the downward motion starts, the valve 35 
closes and a vacuum is created in the chamber between the valves 33, 35. 
The resulting positive pressure above the valve 33 moves fluid from the 
container downward through the valve 33, with the flapper 56 being moved 
away from the shoulder 54, and the chamber is filled with a predetermined 
amount of fluid as the dispenser returns to the position of FIG. 1, ready 
for another dispensing operation. 
With the plunger outlet in the form of a spout above the end of the plunger 
and at an oblique angle, the liquid flow from the dispenser contacts the 
user's hand in the order of a half to an inch away from the end of the 
plunger. This configuration tends to protect the end of the plunger from 
staining and becoming dirty or caked with dried material. The more viscous 
liquids tend to stay in the area of contact with the hand and not run 
towards the lower end of the plunger. The less viscous liquids may contact 
the lower end of the plunger but run off quickly. The seal 39 prevents 
leakage around the plunger. 
In the preferred plunger configuration illustrated, the oblique passage of 
the plunger is at about 30 degrees from the vertical, and the lower end of 
the oblique passage is about one inch above the lower end of the plunger, 
with the lower end of the passage in the order of one half inch laterally 
from the center of the plunger. It has been determined that such an 
arrangement achieves the desired operating characteristics for the usual 
range of fluid viscosities, while avoiding splashing and dripping. 
The design of the valve provides for a relatively high compression ratio 
which is desirable, since this permits a higher negative pressure within 
the cylinder and faster priming and cylinder refilling. Also with this 
construction, the dispenser provides a suction action sufficient to draw 
in liquid with a head of up to forty inches. 
The compression ratio is defined as the volume of liquid inside the chamber 
at the rest position of FIG. 1 divided by the volume of liquid inside the 
chamber at the compressed position of FIG. 2. The specific design 
illustrated in the drawings with a 0.312 inch stroke provides a 
compression ratio of approximately 2.125. 
A dispenser which is capable of holding a head of 40 inches normally is 
difficult to operate because a large suction is needed to draw fluid into 
the valve chamber. Hence a relatively high manual force is required for 
dispensing the fluid. The present dispenser provides both the high head 
holding capability, thereby reducing leakage, and the low manual operating 
force by having the high compression ratio. 
There are a number of advantages in the disclosed preferred embodiment of 
the one way valve 33. This is a self-contained unit which can hold a head 
substantially greater than that normally encountered in the dispenser 
design. A typical dispenser is not more that about 8 inches tall; in 
contrast the valve of the invention will hold a head up to about 40 
inches, thereby providing a substantial excess of head holding capacity 
and thus security against leakage. 
Also the self contained capsule valve as disclosed can be made considerably 
smaller than the conventional umbrella valve, while providing better 
operating characteristics. 
The capsule valve design permits large flow passages through the washer and 
the seal and therefore is much less susceptible to clogging than the 
conventional umbrella valves and ball and spring valves. 
The design of the preferred embodiment will handle both vicous lotions and 
non-vicous liquids, while requiring an upward force of less that five 
pounds for operation. Since the dispenser is a positive displacement 
device and not open to the atmosphere, there is less likelihood of the 
contents drying out. The valve at the top of the container functions as a 
breather valve and allows air only to flow in. Preferably, the container 
itself is molded of a somewhat flexible plastic which will permit 
expansion with increases of ambient temperature. Also, this breather valve 
prevents leakage of liquid when the container has been inverted during 
filling.