Aerosol valve having means to shut off flow if valve is tipped beyond a certain inclination from vertical

In an aerosol valve the flow path includes a compartment having an inlet into the compartment and a valve seat at the upper end of the compartment, a pocket is disposed downward from the seat opening, the pocket containing a gravity-responsive ball. When the valve is being used in dispensing and is tipped in a direction which brings the ball closer to the flow through the compartment, the ball becomes entrained in the fluid flow and flies up to seat on the valve seat to block it off, precluding further discharge. When the aerosol valve is released, a bypass raises the pressure inside the valve body so that the ball will fall away from the seat. The purpose is to avoid the escape of propellant which might occur in tipping if the lower end of the dip tube is exposed to the head space.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
This invention relates to an aerosol valve having means to cut off the 
discharging flow when the container is tipped. 
There has always been a need to cut off discharging flow when an aerosol 
can is tipped. The need is greater now. With the environmentally mandated 
prohibition of chloroflorocarbons and hydrocarbons propellants, the 
aerosol industry bas turned to pressurized gas propellants, especially 
nitrogen and carbon dioxide. Nitrogen and other pressurized gases, having 
relatively high vapor pressure, are not as ideal as some 
chloroflorocarbons or hydrocarbons because they do not change from liquid 
phase to gaseous phase and permit the pressure to recover as part of the 
propellant is used up or lost. Nitrogen and carbon dioxide do not go into 
liquid phase at practical pressures used in aerosol containers. 
To permit the tilting of the container during dispensing runs the risk of 
the bottom of the dip tube being exposed to the head space above the 
liquid which would let the pressurized gas above the product escape. Any 
such escape cannot be tolerated a compressed gas system. 
2. Description of Related Art including Information Disclosed under 
.sctn..sctn.1.97 to 1.99 
While the aerosol valve art is extensive, there is no satisfactory answer 
to the problem described above. 
The U.S. Pat. No. to Braun 3,315,693 which issued Apr. 25, 1967, discloses 
an attachment structure in which a gravity-responsive ball normally blocks 
a passage in an aerosol valve to the outside of the valve body, but, when 
the can is inverted, the ball drops to permit passage of the product into 
the valve body. With the valve body filled with and submerged in product, 
there is no way for the gas pressure in the head space to escape, and it 
performs its normal function of pressuring the product out through the 
valve outlet. This is an example of an "invertible valve". 
There are other examples of such structures, one being the U.S. Pat. No. 
4,728,692 to Meurescb et al issued Feb. 9, 1988. In this patent a 
one-piece valve body with conventional appearance from the outside has an 
inside chamber for a ball-operated valve also accessible to the outside of 
the valve body for when the aerosol can is inverted. The operation is the 
same as in the Braun structure. 
In U.S. Pat. No. 2,954,904 which issued Oct. 4, 1960 to Potoczky an overcap 
is provided which connects to the aerosol valve stem by way of a flexible 
diaphragm under a flexible top panel of the cap. A ball is disposed 
between the diaphragm and the top panel, both the diaphragm and top panel 
being downwardly inclined toward their centers. In normal vertical 
disposition of the can, the ball rolls toward the center of the overcam 
immediately above the stem, and when it is desired to operate the aerosol 
valve therebelow, below, one merely presses the center of the overcap top 
panel and the depressing force acts through the ball to depress the center 
of the diaphragm and the valve stem. Such an arrangement is fine for 
assuring that the can be vertical when the aerosol is operated. However, 
it does not serve to function as a cut-off if the operation is commenced 
while the can is vertical and the can is then tilted to a position, say, 
where the bottom of the dip tube is exposed to the head space. 
Another U.S. Pat. No. 3,186,605 to Potoczky issued Jun. 1, 1965 shows a 
functionally similar but differently structured arrangement. 
SUMMARY OF THE INVENTION 
The present invention is concerned with means for cutting off the flow of 
aerosol whenever the can is tilted to a point at which the bottom of the 
dip tube is exposed or is in danger of being exposed to the head space. 
In the present invention a more or Less standard aerosol valve comprises a 
cup-shaped body with a valve therein, the body having at its lower end a 
tubular tailpiece with dip tube attached. This structure constitutes a 
flow path up the dip tube through the tailpiece into the valve body and 
out through the valve stem when the stem is depressed. The flow path also 
includes a compartment having an inlet into the compartment and a valve 
seat at the upper end of the compartment circumposing an outlet from the 
compartment. A pocket is disposed downward from the seat opening, the 
pocket containing a gravity-responsive ball. 
In use, when the can is tipped in a direction which brings the ball close 
to the flow through the compartment and the aerosol valve is turned on, or 
is already on, the ball becomes entrained in the fluid flow through the 
inlet and flies up to seat on the valve seat to block it off, precluding 
further discharge. 
The invention also includes means, once the aerosol valve is off, for 
unseating the ball by raising the pressure inside the valve body when the 
ball is seated so that ball will fall away from the seat. Such means may 
be a bypass passage from compartment into valve body. In versions in which 
the compartment is secured to the lower end of the aerosol valve, the 
bypass from the compartment into the valve body is blocked when the 
aerosol valve is depressed.

DESCRIPTION OF THE PREFERRED EMBODIMENT 
An aerosol valve embodying the invention is generally designated 10 in FIG. 
1. It comprises a cylindrical valve body 12 thickened outwardly at its 
upper end 14 and having the usual filling castellations 16 outward 
therefrom. An annular gasket 18 is disposed across the top of the valve 
body centered by the inner margins of the castellations. The conventional 
mounting cup pedestal 20 which bas a flat top as at 22 is crimped over the 
thickened top end 14 to secure the valve body and gasket in place. 
A valve element 24 comprising an enlarged bead 26 having an annular opening 
28 in the bottom thereof bas an upward tubular stem 30 and generally 
radial ducts 32 extend outward from the inside of the tubular stem and are 
closed off by the snug fitting resilient gasket 18. 
As shown, the upper end of the bead 26 carries an annular sealing ring or 
ridge 34 which enrages the underside of the gasket 18 to further seal the 
unit. The cylindrical valve body 12 has an integral floor 36 and the 
sidewalls of the body extend down beyond the floor to define an upward 
socket 38. Centrally the floor 36 is formed with an passage 40 into the 
valve body. As shown, the passage 40 may be chamfered about its lower end 
to present a valve seat. A spring 39 is disposed compressively between the 
floor 36 and the annular recess 28 in the valve element, urging the valve 
element 24 upward to seat on gasket 18. 
An appendage 42 bas a circular side wall 44 which is frictionally held in 
the socket at the bottom of the valve body and is pressed inward to engage 
the underside of the floor 36. The sidewall 44 defines therewithin a 
compartment 48. It comprises, aside from the circular side wall 44, a 
tailpiece 46 for leading product into the compartment. 
As shown, the passage in the tailpiece 46 is narrowed into passage or inlet 
50 and extends upward to pass by the outside of a pocket 52 in which is 
disposed a gravity-responsive ball 54. The upper end of the appendage 42 
has an upward sealing rim 56 which in assembly seals against the underside 
of floor 38. 
FIG. 2 shows the valve of FIG. 1 tipped at an angle of 45.degree.. At this 
point, with the stem depressed so that the contents of the container can 
otherwise discharge, the ball 54 moves in its pocket toward the passage 50 
such that the ball becomes entrained in the fluid and flies up to seat on 
the chamfered compartment outlet passage 40, cutting off further flow. 
The angle to which the valve must tilt before the ball 54 moves up to block 
the outlet 40 depends on a number of factors including the flow rate of 
fluid through the fluid path; the nature of the fluid passing--whether the 
fluid is a thin liquid such as perfume or a heavier substance, such as 
furniture polish--and the weight and size of the ball 54. The ball, for 
instance, may be a steel ball having a diameter of 1/8 inch and a specific 
gravity of 8 or a plastic ball having a specific gravity of 1.3. The 
lighter the ball, the quicker it is to fly up and block off the passage 
40. 
By experimenting with different flow rates of product and different 
gravity-responsive balls, s ball can be selected to fly up when the tip is 
the desired angle or, ideally, only after the product has discontinued its 
movement upward and is followed by the pressurized gas propellant in the 
bead space. This, of course is desirable in that discharge of the product 
is the ultimate aim of an aerosol valve and the flow through the valve 
should only be interrupted when there is actual discharge of gas. 
If it is necessary only to assure that no gas discharges, a convenient 
angle beyond which the container cannot be tipped without having the ball 
block the inlet 40 is 45.degree.. Product flow, dictated by viscosity, 
will influence the exact degree at which the valve 10 is tipped prior to 
valve shutoff. 
It will be understood that the shutoff action at the prescribed angle is 
dependent on the valve and container being tipped in the right direction. 
This may be assured by the proper orientation of an overcap including an 
actuator button, the overcap being such that the tendency is to operate 
with the index finger and tilt the container in the same direction as the 
index finger points. If the container and valve are tipped in a different 
direction from that of the FIG. 2 showing, the shutoff will work but at a 
greater angle of tip than the prescribed angle. 
Once the ball as described has blocked the outlet passage 40 and the 
aerosol or main valve is released so that the spring 39 closes the valve, 
it is necessary to assure that the ball in the compartment 48 moves away 
from the outlet 40. The ball may stay on the seat because the pressure in 
the main valve body 12 is lower than the pressure in the compartment 48. 
FIG. 1 discloses a bypass passage 60 for this purpose. The lower end of 
the passage 60 communicates with the compartment through a channel 62 
formed in the top of the appendage as shown in FIG. 3. The passage 60 is 
disposed in an inward enlargement 64 of the side wall of the body 12. 
The passage 62 is abruptly narrowed in the version shown anti terminates in 
a circular upward lip 66. When the actuator button is depressed, lip 66 is 
butted against by the bottom of the flat valve element bead 26. This 
valves off the passage 60 when the valve element is depressed so that 
during use all discharge of product comes through the outlet 40. When the 
valve is allowed to rise, the lip 66 is is exposed, and pressure passes 
freely from the compartment 48 up into the aerosol valve body, permitting 
the ball 54 to drop, opening outlet 40. 
In the FIGS. 5 and 6 embodiment the same reference numerals with 100 added 
are applied as in the FIGS. 1 through 4 embodiment. In the FIG. 5 
embodiment the passage 160 terminates upwardly in an outlet through an 
upward incline wall 70. The underside of the head 126 of the valve element 
is chamfered at 72 about its periphery at the same angle as the sloping 
wall 70 so that as the valve element 126 is depressed, the chamfered 
section 72 engages the sloping wall 70 and cuts off the upper end of 
passage 160. 
The operation of the FIGS. 5 and 6 embodiment is similar to FIGS. 1 through 
4 embodiment in that during operation the passage 160 is closed by the 
chamfered section of the bead 126 and all flow comes through the 
compartment outlet 140. If the valve is tipped and the ball 154 seats over 
outlet 140, the mere release of the valve element permits it to raise, 
opening the outlet for passage 160 equalizing pressure in the compartment 
148 and inside the valve body. 
A far simpler arrangement is disclosed in FIGS. 7 and 8 wherein the same 
reference numerals are used with 200 added. Rather than a bypass down into 
compartment 48, a minute vapor tap 80 is provided in the side wall of the 
valve body in FIG. 7. This minute vapor tap (for example 0.004") permits 
communication between the inside of the valve body 212 and the bead space 
so that the ball 254 will not be held on the seat 240 by pressure 
differential after the main valve 224 is released. 
It should be understood that the invention is not limited to the 
embodiments shown, but the invention is instead defined by the scope of 
the following claim language, expanded by an extension of the right to 
exclude as is appropriate under the doctrine of equivalents.