U.S. patent number 3,704,813 [Application Number 04/883,122] was granted by the patent office on 1972-12-05 for valve systems for non-refillable containers.
Invention is credited to George C. Devol.
United States Patent |
3,704,813 |
Devol |
December 5, 1972 |
VALVE SYSTEMS FOR NON-REFILLABLE CONTAINERS
Abstract
Several forms of valve assembly, to be secured permanently to a
container, enable one-time-only filling of the container, for
avoiding dangerously refilled containers. The valve assembly has a
shut-off valve for controlling fluid dispensing. In some forms, the
shut-off valve converts the assembly to its non-fillable condition
as a consequence of the first closing operation of the shut-off
valve. There may be an initially inactive check valve that allows
the container to be filled and becomes a discharge-only check
valve, or a check valve in a dispensing passage may have a parallel
filling passage that is blocked after one use.
Inventors: |
Devol; George C. (Wilton,
CT) |
Family
ID: |
25382034 |
Appl.
No.: |
04/883,122 |
Filed: |
December 8, 1969 |
Current U.S.
Class: |
29/27R;
137/315.18; 82/129; 222/147 |
Current CPC
Class: |
F16K
1/307 (20130101); F17C 13/04 (20130101); F16K
1/305 (20130101); F17C 2205/0335 (20130101); F17C
2205/0382 (20130101); F17C 2205/0329 (20130101); Y10T
29/5109 (20150115); Y10T 82/2524 (20150115); Y10T
137/6035 (20150401) |
Current International
Class: |
F16K
1/30 (20060101); F16K 1/00 (20060101); F17C
13/04 (20060101); B65d 047/02 () |
Field of
Search: |
;222/147,402.16,153,394,395,399,400.7 ;137/315,329.1-329.4 ;141/18
;215/14,17,18,19,21,22,25 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Reeves; Robert B.
Assistant Examiner: Kocovsky; Thomas E.
Claims
What is claimed is:
1. A fluid dispensing valve assembly having a body one end of which
is formed for securement to a container, said body forming a
conduit for filling and discharge flow of fluid, a shut-off valve
operable for controlling the flow of fluid through said conduit,
said shut-off valve having an externally accessible control, and
convertible means in said body in condition initially to
accommodate the flow of fluid through said conduit in both filling
and discharge directions, a portion of said conduit including two
passages in parallel, a check valve in one of said two passages
arranged to pass fluid only in the discharge direction and said
convertible means including means for sealing permanently the other
of said two passages when the valve assembly is to be rendered
non-refillable, said sealing means being operable by the shut-off
valve from the exterior of the valve assembly into its sealing
condition, and means including said body and said shut-off valve
for securely enclosing and guarding said sealing means against
access from the exterior of the valve assembly for reopening the
conduit to the flow of fluid in the filling direction, whereby a
container equipped with the valve assembly may be evacuated and
then filled with fluid in the initial condition of the valve
assembly but is substantially non-refillable after conversion of
the convertible means.
2. A fluid dispensing valve assembly having a body one end of which
is formed for securement to a container, said body forming a
conduit for filling and discharge flow of fluid, a shut-off valve
operable for controlling the flow of fluid through said conduit,
said shut-off valve having an externally accessible control, and
convertible means in said body in condition initially to
accommodate the flow of fluid through said conduit in both filling
and discharge directions, a portion of said conduit including two
passages in parallel, a check valve in one of said two passages
arranged to pass fluid only in the discharge direction and said
convertible means including means for sealing permanently the other
of said two passages when the valve assembly is to be rendered
non-refillable, said sealing means being operable by the shut-off
valve from the exterior of the valve assembly into its sealing
condition, said sealing means including an initially open readily
deformable device in said other of said two passages and said
sealing means further including a part operable by said shut-off
valve for deforming said deformable device into a passage closure,
said valve assembly when secured to a container having means
including said body and said shut-off valve for securely enclosing
and guarding said sealing means against access from the exterior of
the valve assembly for reopening the conduit to the flow of fluid
in the filling direction, whereby a container equipped with the
valve assembly may be evacuated and then filled with fluid in the
initial condition of the valve assembly but is substantially
non-refillable after conversion of the convertible means.
3. A fluid dispensing valve assembly having a body one end of which
is formed for securement to a container, said body forming a
conduit for filling and discharge flow of fluid, a shut-off valve
operable for controlling the flow of fluid through said conduit,
said shut-off valve having an externally accessible control, and
convertible means in said body in condition initially to
accommodate the flow of fluid through said conduit in both filling
and discharge directions, said convertible means being convertible
permanently into means obstructing the flow of fluid selectively in
the filling direction, said shut-off valve including a part
cooperable with said convertible means for effecting conversion
thereof into said obstructing means in the closing operation of the
shut-off valve, said valve assembly when secured to a container
having means including said body and said shut-off valve for
securely enclosing and guarding said obstructing means against
access from the exterior of the valve assembly for reopening the
conduit to the flow of fluid in the filling direction, whereby the
first closing operation of the shut-off valve following a filling
of the container causes automatic conversion of the valve assembly
to its non-refillable condition, and whereby a container equipped
with the valve assembly may be evacuated and then filled with fluid
in the initial condition of the valve assembly but is substantially
non-refillable after conversion of the convertible means.
4. A fluid dispensing valve assembly having a body one end of which
is formed for securement to a container, said body forming a
conduit for filling and discharge flow of fluid, a shut-off valve
operable for controlling the flow of fluid through said conduit,
said shut-off valve having an externally accessible control, and
convertible means in said body in condition initially to
accommodate the flow of fluid through said conduit in both filling
and discharge directions, a portion of said conduit including two
passages in parallel, said convertible means including a check
valve in one of said two passages arranged to pass fluid only in
the discharge direction and said convertible means including means
for sealing permanently the other of said two passages when the
valve assembly is to be rendered non-refillable, said shut-off
valve including a part operable during the closing motion of the
shut-off valve for causing the sealing means to seal said other of
said two passages, said valve assembly when secured to a container
having means including said body and said shut-off valve for
securely enclosing and guarding said sealing means against access
from the exterior of the valve assembly for reopening the conduit
to the flow of fluid in the filling direction, whereby a container
equipped with the valve assembly may be evacuated and then filled
with fluid in the initial condition of the valve assembly but is
substantially non-refillable after conversion of the convertible
means.
5. A fluid dispensing valve assembly having a body one end of which
is formed for securement to a container, said body forming a
conduit having only one through passage for filling and discharge
flow of fluid, a shut-off valve operable for controlling the flow
of fluid through said passage, said shut-off valve having an
externally accessible control, and convertible means in said body
comprising an initially inactive check valve initially in condition
to accommodate the flow of fluid through said passage in both
filling and discharge directions, said check valve being
convertible after an initial filling operation into an active check
valve in said passage in series with said shut-off valve, said
initially inactive check valve including a movable valve member, a
valve seat, means for biasing said valve member toward said valve
seat, and detent means effective initially to prevent the
cooperation of said valve member with said valve seat, said detent
means being defeatable after an initial filling operation to enable
said valve member to engage said seat, said check valve when active
being operative to pass fluid only in the discharge direction, said
check valve after being rendered active to obstruct the flow of
fluid selectively in the filling direction being guarded against
access from the exterior of the valve assembly when secured to a
container for reopening the passage to the flow of fluid in the
filling direction, whereby a container equipped with the valve
assembly may be evacuated and then filled with fluid in the initial
condition of the valve assembly but is substantially non-refillable
after conversion of said convertible means.
6. A valve assembly in accordance with claim 5, wherein said
shut-off valve has means for releasing said movable check-valve
member from said detent means for thereby activating the check
valve.
7. A valve assembly in accordance with claim 5, wherein said
shut-off valve has a stem bearing an external manual operating knob
constituting said external control, and a movable member carried by
said stem for driving said movable check-valve member past said
detent means during the initial closing operation of the shut-off
valve.
8. A valve assembly in accordance with claim 5, wherein said
shut-off valve has a movable valve member and a seat, the movable
member being normally biased against said seat, and wherein said
externally accessible control is a valve stem arranged to lift said
movable valve member from said seat, and an internal part operable
by said valve stem for driving said movable check-valve member past
said detent means during the operation of the movable valve member
in the valve-opening direction.
9. A valve assembly in accordance with claim 5, wherein said detent
means is of a material related to the liquefied fluid fill of the
container on which the valve assembly is to be used so as to be
rendered soft and thus to be disabled as detent means after
substantial exposure to the liquefied fluid fill.
10. A valve assembly in accordance with claim 5, wherein said
movable check-valve member is adapted to be shifted into active
cooperation with its seat due to its inertia in response to an
impact-induced shift of the valve assembly.
Description
The present invention relates to non-refillable containers and in
particular to a valve system for such containers having provision
for a first-time filling operation.
Many forms of liquefiable fluids are sold in disposable containers.
Small metal tanks containing liquefied propane, liquified butane,
and refrigerants such as freon are common examples of this
practice. When containers of this type are filled by a manufacturer
who has full control of the starting condition of the container and
of the filling procedures and the specifications, a remarkably safe
product can be distributed to the public. However, sometimes empty
or partly empty containers are collected and these are refilled by
poorly skilled and poorly equipped persons. The result is often a
hazardous product. For example, an overfilled container can be a
real danger to life and property.
An object of the present invention resides in providing a valve
system for containers of liquefied gas under pressure for allowing
the container to be filled initially and in which the valve system
can then be modified expeditiously and in a virtually permanent
manner by the persons responsible for the first filling, for
preventing subsequent filling operations.
Another object of the invention resides in providing a valve system
for dispensing liquefied fluid from a container in which there is
provision for a first-time filling operation, readily modified
after the first fill so that any attempts to refill the container
would necessitate tampering and would leave tell-tale marks. This
feature is aimed at providing a defense for the manufacturer who
originally filled the container in case the container should later
be refilled by another and then be involved in a harmful
mishap.
A related object resides in providing novel methods of filling
fluid containers through a valve system that is subsequently used
for dispensing the fluid, involving relatively secure modification
of the valve system to virtually prevent subsequent refilling of
the container.
A still further object resides in the provision of methods and
apparatus for filling containers of the aforementioned type in a
way to provide assurance that the valve system has been converted
to its fill-preventing condition once the original filling
operation has been completed.
The foregoing and other objects of the invention and its various
features of novelty and their advantages will be more fully
appreciated from the description below of several illustrative
embodiments of the invention which are shown in the accompanying
drawings. In each of these embodiments there is a valve system for
controlling the flow of fluid between an external port where fluid
is supplied or discharged and an internal port that opens into the
container. The valve system is contained in a short conduit secured
permanently to the container. It includes a shut-off valve that has
an externally accessible operating part for opening the discharge
passage when required, and a check valve for preventing the flow of
fluid in the filling direction after the container has once been
filled. The check valve is virtually inaccessible so that it
remains effective to prevent a refilling operation. In each
embodiment, the valve system includes provision for an initial
filling operation that can be readily and securely modified for
preventing refilling.
In the initial condition of several embodiments, the check valve is
prevented from seating by a detent. This condition allows the
check-valve passage to be used in a filling operation. After the
container has been filled, this detent is disabled. The check valve
assumes its operative configuration for preventing flow of fluid in
the container-filling direction. The check valve and its detent are
virtually inaccessible for restoring the detent to its condition
needed for holding the check valve open, such as would become
necessary for refilling the container.
In one form, the check valve includes a ball that is spring biased
toward a seat and arranged to allow flow of fluid in the
discharging direction. However, before the container has been
filled, a cluster of spring-fingers acts as a detent holding the
ball away from the valve seat and thereby provides a passage for
the flow of fluid in the filling direction. The shut-off valve of
the valve system is open, and the container is filled under
controlled conditions. Thereafter, the ball is forced past the
detent fingers to cooperate with its valve seat. The movable member
of the shut-off valve is used to force the ball of the check valve
past its detent fingers. From this point on, there is no practical
way of gaining access to the check valve for opening it in an
attempt to refill the container.
In another embodiment involving a convertible check valve, the
check valve is held open by a wire that extends from the external
port of the valve system to a rupturable connection to the movable
member of the check valve. After the filling operation has been
completed, the wire is torn away, and the movable valve member of
the check valve thereupon becomes effective for preventing flow of
fluid in the filling direction while freely accommodating flow of
fluid in the dispensing or discharging direction.
In another form involving a convertible check valve, there is a
temporary support or detent that initially holds the movable valve
member at some distance from its seat. The support or detent is
made of material that is attacked by the filling fluid. It may be
dissolved, or it may be severely softened. After the container has
been filled, the detent loses all capacity to hold the valve open
to the flow of fluid in the filling direction. In a still further
construction, the check valve has parts that are initially out of
effective check-valve cooperation, but after the initial filling
operation, a properly directed impact shifts the parts of the check
valve permanently into check-valve configuration.
In each example mentioned above, the valve system has a single
passage that serves both for the initial filling operation and
subsequently for check-valve controlled discharge of fluid. The
check valve is in that passage, and it is convertible from an
initially disabled freely open condition utilized during the
initial filling operation into active check-valve configuration to
block subsequent flow in that passage in the filling direction. In
a further modification, there are two parallel passages between an
inner port and an outer port of the valve system, one passage being
controlled by a check valve and the other passage being initially
open to provide a filling passage but which is blocked after the
initial filling operation. A shut-off valve is included, for
controlling the delivery of fluid from the container.
In both the one-passage system and the two-passage valve system
described above briefly, certain embodiments in common follow the
concept of utilizing the shut-off valve (which is notably
accessible externally) as a tool or probe that reaches deep into
the valve system to convert the system from its filling condition
to its non-refillable condition.
In the routine operation of a plant where containers are filled
with liquefied fluid, the containers equipped with the novel valve
system are successively evacuated and filled. A procedure that is
then carried out as part of the routine is to convert the inactive
check valves to their active state. It is of course possible for an
occasional unit to be overlooked so that there could be isolated
instances of inactive check valves. However, so long as most of the
check valves are made active, there would be little incentive for
anyone to set himself up as a refilling facility.
It is nevertheless desirable for the foregoing valve systems to be
rendered non-refillable automatically after the first filling of
the container. Two forms of apparatus that insure conversion of the
convertible valve systems of the present invention to their
non-refillable condition after filling is completed are described.
In one example of the filling apparatus, the filling valve in the
container filling apparatus is coordinated with the device that
converts the valve system to its non-refillable condition. The
check valve remains in its initial condition both while the filling
valve is open and while it is closed and also when it is being
opened for a filling operation; but when the filling valve is being
closed, thus signalling completion of the filling operation, the
filling valve automatically causes the valve system conversion to
its non-refillable state. In a second example of the filling
apparatus, the removal of the valve system from the evacuating and
initial filling apparatus is made dependent on the activation of
the valve-system converting device. Thus, there is an automatic
safeguard against operator error, providing assurance that
initially fillable containers cannot remain in their fillable
condition after having been filled once.
The foregoing embodiments which have been thus briefly described
are shown in the accompanying drawings, wherein:
FIG. 1 is a lateral view, drawn to reduced-scale, of a liquefied
gas container and a valve system for filling the container and for
discharging fluid as required;
FIG. 2 is a longitudinal cross-section of a valve system on a
fragmentary portion of the container of FIG. 1, FIG. 2 being drawn
to enlarged scale and representing an embodiment of several
features of the invention;
FIG. 3 is a longitudinal cross-section of a modification of the
valve system of FIG. 2;
FIG. 4 is a fragmentary longitudinal cross-section of a
modification of the valve system in FIG. 3;
FIGS. 5 and 6 are two further valve systems for one-time filling
and for controlled discharge or dispensing of fluid from the
container of FIG. 1;
FIG. 7 is a fragmentary vertical cross-section of another
embodiment of certain features of the invention;
FIG. 8 is an enlarged fragmentary vertical cross-section of the
valve system in FIG. 7;
FIG. 9 is a fragmentary vertical cross-section of a further
embodiment of certain features of the invention;
FIG. 10 is a fragmentary vertical cross-section of the embodiment
of FIG. 9 following operation thereof for conversion to the
non-refillable state;
FIG. 11 is a lateral view of one form of apparatus for use in
filling containers having valve systems of a form such as that in
FIGS. 2, 3 and 4; and
FIG. 12 is a lateral view, partly in cross-section, of another form
of apparatus for use in filling containers having valve systems as
shown in FIGS. 6, 9 and 11.
Referring now to the drawings, container 10 has a valve system 12
secured to one end thereof. Valve system 12 is shown enlarged in
longitudinal cross-section in FIG. 2. Collar 14 is welded or
otherwise hermetically joined to the wall of container 10. A
flanged part 16 of the valve system in FIG. 2 is held firmly in
place in its complementary cavity in collar 14 by a turned-in or
spun-over edge portion 15 of the collar. An "O-ring" 20 that is in
compression between flange 16 and collar 14 provides assurance of a
hermetic seal between the collar and body 18. Portion 15 of the
valve system mounting is to be permanent in the sense that it can
be reworked only with such great difficulty as to be readily
detected. The metal of which flange 15 is made is hard or otherwise
of such character that if it were raised to release flange 16 and
turned down again, it would fracture. Other secure fastening
techniques may be used.
Threaded portion 22 of body 18 provides a coupling for a companion
threaded coupling or fitting of a supply line or a receiving line.
Stem 24 of pressure relief valve is slideable along a bore in body
18 at the axis of coupling 22. A number of lengthwise passages
around stem 24 provide a composite external port 26 for the valve
system. Body 18 provides a through conduit to an internal port 28
that opens into the container 10.
Member 30 has a force fit or is otherwise fixed in the bore surface
32 of body 18. A firm compression spring 34 bears against the end
of member 30 and presses upward against cup 36 of a shut-off valve.
This cup and resilient ring 38 form the movable member of a
shut-off valve. Resilient ring 38 bears against annular rib 40 that
forms the shut-off valve seat. Cup 36 has a number of ribs 42 that
are spaced apart and provide a slide bearing for the cup against
bore surface 32. When the shut-off valve is open, the spaces
between ribs 42 provide a passage past cup 36 for the flow of fluid
through body 18.
An annular rib 44 surrounding a cavity in the center of cup 36
forms the seat for a pressure relief valve. Disc 46 of resilient
non-porous material such as rubber and a cup portion 48 that has a
tubular extrusion joined to valve stem 24 form the movable member
of the pressure relief valve. A compression spring 50 biases valve
member 46, 48 against its seat 44. One or more holes 52 in the
hollow conical tip 54 of valve cup 36 provides a passage for escape
of excess-pressure fluid via internal port 28, bore 32, hole 52,
and the space 56 surrounding spring 50 to the passages forming exit
port 26. The compression of spring 50 is selected in relation to
the area within valve seat 44 so that an excess pressure in
container 10 will lift valve member 46 to provide pressure relief.
Spring 34 which biases valve cup 36 upward is much more powerful
than spring 50 so that there is no tendency for the pressure relief
valve to open the shut-off valve 38, 40.
Member 30 has a cluster of spring fingers 58 around a seat 60. Ball
62 is initially supported by fingers 58 in the position
illustrated. Compression coil spring 64 has its upper end centered
about the generally conical center projection 54 of valve cup 36.
Spring 64 bears against ball 62 and biases that ball against spring
fingers 54. This is a relatively light biasing force, sufficient to
maintain ball 62 in the position illustrated, against spring
fingers 58.
The operation of the valve system of FIG. 2 is as follows. The
parts in the positions illustrated in FIG. 2 represent the valve
system in condition for a filling operation. The valve system is
first coupled to a vacuum line, using a fitting that depresses
shaft 24 flush with the end of the coupling 22. This opens the
shut-off valve 38, 40. When the container has been evacuated, the
vacuum line can be disconnected, the shut-off valve closing
automatically. The valve system is then coupled to a fluid-filling
line, again depressing stem 24 and opening shut-off valve 38, 40.
When the container 10 has been filled according to specifications,
the valve system is released from the filling station. As a matter
of routine, an attendant uses a suitable rod to depress stem 24 far
enough to drive ball 62 to its dotted-line position. This activates
the check valve. Subsequent refilling of the container is
prevented, short of drastic steps that would leave tell-tale
marks.
Conversion of the check valve 60, 62 from its inactive to its
active state is carried out automatically by the apparatus of FIG.
12. Threaded coupling 22 is screwed into internally threaded part
100 of a filling unit. For convenience, part 100 is made rotatable
relative to the filling unit so that coupling 22 on container 10 is
drawn into part 100. A shaft 102 is held captive in bore 104 by a
snap-ring 106, and O-ring 107 provides a seal between shaft 102 and
bore 104. A part 108 of shaft 102 depresses the upper end of stem
24 so as to be flush with the upper end of coupling 22 when ring
106 bears against the top of cavity 110 and when fitting 22 is
seated in part 100. This depression of stem 24 lifts the movable
member 36, 38 of the shut-off valve away from its seat 40 (FIG. 2)
and opens a passage from the external port 26 through the conduit
formed by body 18 from coupling 22 to the internal port 28.
Valve 112 controls the connection of passage 113 to a vacuum pump
connected to rotatable internally threaded fitting 114. Valve 112
is opened for evacuating container 10, and then valve 112 is
closed. At the same location or at another location in the plant,
rotatable internally threaded fitting 120 is connected to a supply
of pressurized fluid. Valve 118 is opened by rotating valve handle
116 for filling container 10.
Valve 118 has a disc 120 on the valve stem. When the filling valve
is to be opened, disc 120 rotates counterclockwise as observed
looking downward, i.e., in the direction of the arrow. In the
position shown, the valve 118 is closed. As the valve starts to
open, arm 102a on shaft 102 moves in a circular groove 122. Pin
102b prevents arm 120a from swinging away from groove 122. Bar 124
is pivoted to an area 126 at the outer surface of disc 120, and is
normally biased against pin 128 by a spring (not shown) so as to
extend slantwise across groove 122. During opening of the valve,
disc 120 rotates and bar 124 swings out of the way of arm 102a.
Depending on the design of valve 118, it may be sufficient to
rotate handle 116 one revolution to open the valve, and in that
case bar 124 snaps out of the way of arm 102a only once.
When container 10 has been filled according to specifications,
valve 110 is closed. Disc 120 rotates opposite to the arrow and bar
124 forces arm 102a to follow groove 122a. This depresses the upper
end of rod or stem 24, pressing members 46 and 36 downward until
the tip of conical member 54 drives ball 62 past the detent
represented by spring fingers 58 and into the dotted-line position
illustrated. Spring 64 continues to bear lightly against ball 62,
biasing the ball against its seat 60. Thus, ball or movable valve
member 60 which is biased toward its seat 60 by spring 64 acts as a
check valve preventing flow of fluid in the filling direction from
external port 26 to internal port 28. At the same time this check
valve allows reverse flow of fluid in the discharging direction
from internal port 28 to the external port 26. The flow of fluid in
the discharging direction occurs only when the coupling of a fluid
receiver is attached to threaded coupling 22 and stem 24 is
depressed to open the shut-off valve 36, 38, 40. Additionally, it
is evident that ball 62 would lift from its seat in the event of an
excess pressure developing in container 10, providing a passage
from internal port 28 via (open) check valve 60, 62, through hole
or holes 52, through (open) pressure relief valve 44, 46 and to the
exterior via space 56 and external port 26.
Shifting of ball 62 to the dotted-line position of FIG. 2 activates
the check valve of the valve system on container 10, the valve
system of container 10 thus assuming its non-refillable condition.
The operation of closing the fluid supply valve 118 must be done
before fitting 22 of the valve system on container 10 can be
released from part 100. This provides the definite assurance of the
check valve being activated to prevent subsequent filling, as an
incident of the initial filling operation.
Repeated operation of shut-off valve 36, 38, 40 for opening the
passage through the valve assembly has no effect on check valve 60,
62 after the spring-finger detent 58 has been forcibly deflected
out of the path of ball 62. The check valve remains effective
thereafter and is virtually inaccessible for being restored to the
position represented by the solid-line showing of ball 62, to
return the valve to the condition necessary for a refilling
operation.
In some situations it is considered desirable for the valve system
to incorporate a safety valve having an exit port that does not
extend into either the fluid supply or the fluid receiver. A
modified construction like FIG. 2 is shown in FIG. 3, wherein like
parts have the same numerals as in FIG. 2, distinguished by a
suffix a. The like parts and their operation will be understood
from the description of the valve system of FIG. 2, and the filling
operation follows that of the embodiment in FIG. 2.
In FIG. 3, pressure relief valve 44a, 46a, 48a has a stem 24a' that
is separate from the stem 24a which carries cup 36a of the shut-off
valve. The pressure relief valve opens to an exit port 26a' that is
external of coupling 22a and separate from external port 26a of the
valve assembly. In the lateral position of the pressure relief
valve in FIG. 3, that valve can respond to an over-pressure and
vent to the outside atmosphere even when the fluid supply (FIG. 12)
or a fluid receiver is connected to coupling 22a. A spacer ring 66
lifts the lower end of body 18 off the face 68 in collar 14a so
that there will be a fluid passage from internal port 28a into the
bore 32a and into the passage of the pressure-relief valve. Holes
52 of FIG. 2 are unnecessary in the shut-off valve cup 36a of FIG.
3.
A modification of the valve assembly of FIG. 3 is shown in FIG. 4,
wherein only enough of the valve assembly is illustrated to show
the modification. The parts in FIG. 4 that correspond to those in
FIG. 3 bear the same reference numerals with a suffix b.
Fingers 58a which are shaped as detents in FIG. 3 for supporting
ball 62a are replaced by a rod 58b in FIG. 4, carried by a
perforated disc 70 that fits tightly in a cavity in member 30b.
Ball 62b is supported by rod 58b, and is guided laterally by
upstanding straight fingers 72. As in FIGS. 2 and 3, there is a
light spring 64b that bears downward against ball or movable
check-valve member 62b. Member 70 and its post 58b are formed of a
material that softens or is dissolved by the fluid with which the
container is filled. The solubility should be limited so that the
filling operation can proceed to completion. In the case of a
refrigerant such as freon, an acrylic plastic can be used. Once the
filling operation is complete and the post 58b has softened or
dissolved and has thus been removed from its position supporting
check-valve member 62b, that valve member moves against its seat
60b. The parts of the check valve are remote and inaccessible from
the exterior of the valve assembly. Due to the valve location,
tampering with the check valve for refilling the container is
virtually impossible. The valve assembly will provide for the
discharge of fluid whenever the shut-off valve is opened, but
refilling of the container is prevented by check valve 60b, 62b,
64b after it is activated. This form of valve assembly makes the
container fillable once, and it inherently prevents refilling even
without a specialized filling apparatus such as that of FIG.
12.
A further form of valve system having the same broad
characteristics of the assemblies in FIGS. 2, 3 and 4 appears in
FIG. 5 where the same numerals are used with a suffix c to indicate
corresponding parts. Collar 14c and body 18c are united to each
other and to can body 10 in a secure, hermetically sealed manner.
There is a right-angled passage through the body 18c, forming a
conduit between internal port 28c and and external port 26c. This
passage can be closed off by a manually operable shut-off valve
having a movable member 38c adapted to cooperate with valve seat
40c. The shut-off valve has a laterally threaded stem 74 that mates
with internal threads in body 18c so that, when knob 76 is rotated,
movable valve member 38c of the shut-off valve will close against
its seat 40c and thereby close off the passage from internal port
28c to the exterior. Body 18c has a shoulder 78 that overlies snap
ring 80 contained in a groove around the valve stem. Snap ring 80
abuts against shoulder 78 in the position illustrated, and prevents
removal of the manual valve stem. As valve stem 74 is turned for
driving movable valve member 38c in the valve-closing direction,
snap ring 80 moves along the internal passage 82 in body 18c.
There is a bore 84 in valve stem 74 that communicates with the
internal port 28c. Bore 84 provides a passage to valve seat 44c.
Movable valve member 46c cooperates with valve seat 44c to close
this passage. Member 46c is made of resilient non-porous material
and is contained in a cup 48c. A spring 50c biases valve member 40c
against its seat, constituting a pressure relief valve. A
castellated sharp-edged washer 86 fits in bore 88 and acts as stop
for the upper end of compression spring 50c. Seat 44c, member 46c
and spring 50c form a pressure relief valve which, as in FIGS. 3
and 4, communicates to the atmosphere.
At right-angles to body 18c there is a threaded lateral extension
18c', and internally threaded cap 90 is mounted on lateral
extension 18c'. Mounting of the cap may be rendered permanent by
welding instead of or in addition to the threads. Also, cap 90 and
body 18c may be made of a plastic such as nylon, and they may be
welded by a solvent or bonded by a cement when screwed
together.
An initially inactive check valve is enclosed in lateral extension
18c'. Annular rib 60c forms a valve seat. Resilient member 62c of
resilient non-porous material is supported in a body 62c' forming a
movable member of a check valve. The sides of member 62c' have
grooves 92 forming fluid passages when the movable valve member is
spaced from its seat. A wire 94 has a headed end 96 that is captive
in a cavity formed by small cup 98 whose edges are turned-over
behind head 96. At its opposite end, wire 94 has a looped portion
101 that bears against a shoulder in the external port 26c and in
this condition wire 94 holds movable valve member 62c, 62c' away
from its seat 60c. In this condition, external port 26c can be used
for admitting a fluid filling when valve 38c, 40c is open. Valve
38c, 40c is closed when the filling operation is complete. Then
wire 94 is forcibly removed, spreading the turned-in edges of cup
98. Alternatively, the wire could be weakened adjacent to its head
96 for fracturing easily. In any case, once wire 94 has been
removed, valve elements 60c, 62c, 62c' and spring 64c constitute a
check valve that prevents flow of fluid in the filling direction
while accommodating discharge of fluid from internal port 28c to
external port 26c when shut-off valve 38c, 40c is open.
Filling of a container 10 having a valve system of FIG. 5 can be
carried out by connecting coupling 22c to a vacuum line and then to
a liquefied fluid supply line, closing valve 38c, 40c each time
coupling 22c is to be disconnected. Wire 94 is next extracted at an
established place in the routine of the filling plant. The routine
can also be carried out using the apparatus of FIG. 12 modified,
however, to form part 108 as an extracting hook for wire 94. Curved
track 122a of FIG. 12 would then curve away from the valve system
of the container so as to extract the wire 94 when the filling
valve is closed at the end of the controlled filling procedure.
The additional modification illustrated in FIG. 6 shows a similar
valve system. The shut-off valve of FIG. 6 is identical to that in
FIG. 5 except that there is a fluted extension 103 on the valve
stem 74d that is adapted to drive ball 62d past spring-finger
detent 58d so that the ball can occupy the dotted-line position
illustrated. This is the operative position of the check valve for
accommodating flow of fluid in the discharge direction but
preventing flow of fluid in the container-filling direction. In the
construction of FIG. 6, check valve 62d, 60d, 64d operates the same
as that in FIGS. 2 and 3. The notable distinction of the
construction in FIG. 6 is that the shut-off valve stem 74d must
remain in its full-open position until the container has been
filled. Once valve stem 74d has been operated to drive movable
drive member 38d against its seat 40d, the check valve is
thereafter in its refill-preventing condition. Of course, fluted
rod 103 does not drive ball 62d against seat 60d. The embodiment of
FIG. 6, like that of FIG. 5, involves a right-angled discharge-port
construction.
The routine of evacuating and then filling a container 10 equipped
with a valve system of FIG. 6 requires an external shut-off valve
arrangement, to be used after the container has been evacuated.
This is because shut-off valve 38d, 40d cannot be used until the
time when rod 103 is to drive ball 62d past detent fingers 58d, to
activate the check valve. Alternatively, the filling routine can be
carried out effectively using the apparatus of FIG. 13.
The valve assembly of FIG. 6 is shown coupled to a filling
apparatus 130, including a rotary coupling 132 that is internally
threaded to receive coupling 22d and to seal that coupling to an
evacuating and filling line 134. Coupling 132 has a gear 136 that
is operated by pinion 138 on reversible slow-speed drive unit
140.
After the specified evacuating and filling sequence has been
completed, knob 76 of the shut-off valve is operated for the first
time. It is necessary to operate the valve before removing the
container 10 and its valve system from the filling apparatus, since
otherwise there would be nothing to prevent discharge of the
liquefied fluid from the container. Drive unit 140 contains an
electric motor and a suitable speed reducer. When knob 76 is
operated to close the shut-off valve of container 10, lever 142 is
pressed down against the bias of tension spring 144 to operate
reversing switch 146. Then, when drive unit 140 is energized by a
starting switch, coupling 132 will operate in the direction to
release coupling 22d.
The filled container 10 cannot be removed from the filling
apparatus without a controlling reminder to the attendant to
operate knob 76 of the shut-off valve, thus causing part 103 to
activate the check valve in body 18d and render the valve system
non-refillable.
FIGS. 7 and 8 illustrate still another principle for activating an
initially inactive check valve in a once-fillable non-refillable
valve system for liquefied gas containers. By way of illustration,
this modification utilizes the otherwise-similar valve assembly of
FIG. 3. Corresponding parts bearing like numerals with the e suffix
are alike in form and function.
Spring 34e biases shut-off valve member 38e toward its annular seat
40e. Weaker spring 64e biases a part 150 in the opposite direction.
Part 150 has a cylindrical periphery that is guided in a
cylindrical cavity in member 30e. Ball 62e is initially held
captive by detent means in the position represented in solid lines
in FIGS. 7 and 8. There is a hole 58e' in part 150, and a
projection 58e both of which serve as the detent means. A channel
formed by a pair of walls (including wall 152) guides ball 62e
toward valve seat 60e.
After a container has been evacuated and filled following
prescribed procedures, a sharp blow against body 18e is used to
activate the check valve. A sharp blow at point X causes ball 62e
to shift past its detent means, dropping into a cavity to its
dotted-line position at valve seat 60e. Stop 153 prevents excess
travel of the ball.
Point X can be recognized as being opposite the pressure relief
valve. However, the required path of the ball to activate the check
valve may be changed from one valve to the next. In that case,
point X can be identified by a mark on the body 18e that is of a
form readily removed after the filling operation. In any case, once
the ball has shifted to its valve seat, an enormously larger impact
would be needed to restore the check-valve ball to its initial
position. Thus, this valve system makes the container
non-refillable after the check valve has been activated.
Part 150 has a hole 154 for flow of fluid out of the container when
the shut-off valve is opened, and hole 58e' serves as such an
opening. Spring 64e acting on part 150 biases ball 62e against its
seat.
Check valve 62e-60e-64e is to be activated only on completion of an
evacuating and filling sequence, and it should be activated at that
time. An impact-applying station can be located in the
container-filling plant adjacent to the filling station, so as to
be used as a matter of routine. If a marker is applied to valve
system 12e to indicate point X, the marker should be removed after
impact is applied.
Alternatively, an impact tool can be coordinated with the filling
apparatus. The impact tool can assume the form of an electromagnet
having a hammer-like armature, and the control switch for the
electromagnet can be activated in coordination with filling
apparatus like that of FIG. 11 or FIG. 12. Thus, the electromagnet
control switch can be activated by a suitably modified part 102
(FIG. 12) during the closing operation of the filling valve.
Similarly the electromagnet control switch can be activated by
manually depressing lever 142 (FIG. 12), this control switch being
adjacent to, or part of, reversing switch 146. In this way the
impact for activating the check valve would necessarily occur
before the valve system 12e of container 10 can be disconnected
from the filling apparatus. It will be appreciated that the valve
system 12e and container 10 must be movable at the time of the
impact so that the inertia of ball 62e will cause the ball to
become seated as the whole valve system and the container shift due
to the impact. To accommodate this shift, a length of flexible hose
should be used in the connection of containers 10 to the filling
apparatus of the modified FIGS. 11 or 12.
In each of the various embodiments that have been described above,
there is a deactivated check valve whose parts are maintained
separated by a detent and the valve is accordingly maintained open
during the filling operation; the detent which maintains the
separation of the valve members is overcome or permanently removed
from the detent or obstructing position; and the valve is
thereafter effective as a check valve for preventing flow of
filling liquid while accommodating the flow of liquid in the
discharge or dispensing direction. In each case, the check valve is
so located remote from the exterior in an inaccessible position so
that restoration of the valve to its initial condition for
accommodating a refill operation is virtually impossible.
FIGS. 9 and 10 show a still further approach to realization of a
one-time fillable non-refillable valve system. This modification
includes a valve body 18f and a shut-off valve stem 74f like that
of FIG. 5 and incorporates a pressure-relief valve in the shut-off
valve stem, movable valve surface 38f bearing against seat 40f when
the valve is closed. Body 18f forms a conduit between outer and
inner ports 26f and 28f.
A check valve comprising seat 60f, ball 62f and spring 64f is
disposed in a fluid discharge passage 65f between ports 26f and 28f
allowing discharge of fluid from container 10 when the shut-off
valve is open. A parallel passage is formed by a tube 67f fixed in
body 18f. The upper end of tube 67f is initially open (FIG. 9) for
a first filling operation. Tube 67f is of readily deformable
material such as lead. Valve stem 74f has a cupped extension 74f'
proportioned to close off the upper end of tube 65f (FIG. 10) when
the shut-off valve is closed for the first time. Pressure-relief
valve 84f opens laterally through extension 74f', to communicate
with passage 65f both when the shut-off valve is open and when it
is closed.
Filling of a container having valve system 12f follows the
procedure described in connection with FIG. 5. The check valve is
initially effective in FIG. 9, but tube 67f, a passage in body 18f
between the outer port and the inner port, is open initially for a
first filling operation and is closed thereafter so as to prevent
refilling. The check valve and the convertible structure that
provides a passage for the once-only filling operation is located
deep inside the unit so that tampering for refilling efforts would
inevitably leave tell-tale marks.
The foregoing detailed description of several illustrative
embodiments of various aspects of the invention will inevitably
suggest modifications and still further embodiments to those
skilled in the art, and therefore the invention should be construed
broadly in accordance with its full spirit and scope.
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