U.S. patent number 3,715,032 [Application Number 05/195,202] was granted by the patent office on 1973-02-06 for fluid treatment devices.
Invention is credited to Stanley Nicko.
United States Patent |
3,715,032 |
Nicko |
February 6, 1973 |
FLUID TREATMENT DEVICES
Abstract
Fluid treatment devices are disclosed utilizing a removable and
preferably disposable fluid treatment unit, which may take the form
of a filter, strainer, water softener or the like. The fluid
treatment unit is removably mounted on a valve body which is
arranged to direct the fluid through the treatment unit when it is
mounted on the body. Inlet and outlet ports are preferably formed
in the valve body and are adapted to be connected to the fluid
supply system. The valve body is also preferably provided with
discharge and return ports adapted to be connected to the fluid
treatment unit. An automatic valve mechanism is provided in the
valve body to disconnect the discharge port from the inlet port
when the treatment unit is removed from the body. The outlet port
is also preferably disconnected from the return port. In this way,
no substantial quantity of the fluid will be discharged from the
valve body when the treatment unit is removed. The automatic valve
mechanism also preferably opens a bypass passage between the inlet
and outlet ports when the treatment unit is removed. When a new
fluid treatment unit is mounted on the body, the automatic valve
mechanism is preferably operated so as to close the bypass passage
while opening the normal service passages so that the fluid can
flow from the inlet port to the discharge port, through the
treatment unit, and then from the return port to the outlet port.
Preferably, the valve mechanism is operated by a tube projecting
out of the fluid treatment unit and adapted to be inserted into the
valve body. The tube may be provided by a coupling component,
adapted to receive a disposable canister or the like and arranged
to be removably mounted on the valve body.
Inventors: |
Nicko; Stanley (Lafayette,
IN) |
Family
ID: |
22720428 |
Appl.
No.: |
05/195,202 |
Filed: |
November 3, 1971 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
|
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88874 |
Nov 12, 1970 |
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Current U.S.
Class: |
210/133; 210/234;
210/235 |
Current CPC
Class: |
C02F
1/42 (20130101); B01D 35/153 (20130101); B01D
35/147 (20130101); F16K 11/04 (20130101); B01D
35/147 (20130101); B01D 35/153 (20130101) |
Current International
Class: |
C02F
1/42 (20060101); B01D 46/42 (20060101); F16K
11/04 (20060101); B01D 35/14 (20060101); B01D
35/147 (20060101); F16K 11/02 (20060101); B01d
035/02 (); B01d 027/10 () |
Field of
Search: |
;210/130,134,234,235,133 |
References Cited
[Referenced By]
U.S. Patent Documents
Primary Examiner: Spear, Jr.; Frank A.
Parent Case Text
This application is a continuation-in-part of my copending
application Ser. No. 88,874, filed Nov. 12, 1970, now abandoned.
Claims
I claim:
1. A fluid treatment device,
comprising an exchangeable fluid treatment unit including a
container having coaxial inlet and outlet conduits,
one of said conduits being in the form of a generally cylindrical
axial pipe member projecting from said container,
the other of said coaxial conduits being in the form of a tubular
neck member disposed on said container around said axial pipe
member and spaced outwardly therefrom,
said neck member having a first threaded connecting member
connected thereto and coaxial therewith,
a valve body having inlet and outlet ports for connection to a
supply system,
said valve body having a second threaded connecting member for
mating with said first threaded connecting member to connect said
container to said valve body in an easily removable manner,
said valve body having a generally cylindrical wall member for
mating with said neck member on said container,
a first sealing ring for providing a sliding seal between said neck
member and said wall member,
one of said last-mentioned members having a groove therein for
retaining said sealing ring,
said valve body having a valve mechanism including a valve member
movable in said body between normal service and out-of-service
positions,
said valve member having a bore therein for receiving said pipe
member,
and a second sealing ring for providing a sliding seal between said
pipe member and said bore in said valve member,
one of said last-mentioned members having a groove therein for
retaining said sealing ring,
said valve body having a bypass passage therein,
said valve mechanism including means operable by said valve member
in said normal service position to provide supply passages
connecting one of said ports to the interior of said pipe member
while connecting the other port to the space between said pipe
member and said neck member,
said means being operable by said valve member in said
out-of-service position to close off said supply passages while
connecting both of said ports to said bypass passage,
said valve mechanism including resilient means biasing said valve
member toward said out-of-service position,
said bore in said valve member having a shoulder therein engageable
by the end of said pipe member upon insertion of said pipe member
into said bore and connection of said first and second threaded
connecting members whereby said pipe member is effective to move
said valve member between said normal service position and said
out-of-service position,
the relative positions of said shoulder, said first and second
sealing rings and said first and second threaded connecting members
being made such that said pipe member does not engage said shoulder
until after said first and second sealing rings are engaged by the
corresponding members and fully operative as seals therebetween,
and also until after said first and second threaded connecting
members are mutually engaged to retain said fluid treatment unit on
said valve body.
2. a fluid treatment device according to claim 1,
in which said neck member comprises a third threaded connecting
member,
said container having a fourth threaded connecting member for
disengageably mating with said third threaded connecting
member,
said pipe member being mounted within said neck member and having a
portion for extending into said container, whereby said neck member
and said pipe member are readily removable as a unit from said
container.
Description
This invention relates to fluid treatment devices, such as filters,
strainers, water softeners or the like. The invention is applicable
to the treatment of various fluids, such as water, liquid fuels,
oils, various gases and the like. The illustrated embodiments are
particularly advantageous as water filters having disposable filter
units, but this illustrative disclosure should not be taken as
limiting the applicability of the present invention.
One object of the present invention is to provide a new and
improved fluid treatment device having a fluid treatment unit which
is removable and preferably disposable so that the unit can be
removed and replaced with a new unit, when the old unit has ceased
to function effectively.
A further object is to provide such a new and improved fluid
treatment device in which the fluid treatment unit can be removed
and replaced without allowing any substantial quantity of the fluid
to escape. Thus, the present invention obviates any substantial
loss of the fluid and makes it unnecessary to clean up any
substantial quantity of spilled fluid.
It is a further object to provide a new and improved fluid
treatment device in valve mechanism is provided in the body and is
operable between a normal service position and an out-of-service
when the fluid treatment unit is removed, the normal flow through
the treatment unit being restored when it is replaced.
To off and other objects, the invention preferably utilizes a fluid
treatment unit which is illustrated in the form of a disposable
canister but may assume various other forms. The fluid treatment
unit may comprise a filter, strainer, water softener, or the like.
The fluid treatment unit is adapted to through removably mounted on
a valve body having When and outlet openings.
The body has means forming inlet and outlet ports adapted to be
connected to the fluid supply system. Discharge and return ports
are also provided to be connected to the fluid treatment unit. A
valve mechanism is provided in the body and is operable between a
normal service position and an out-of-service position. When the
fluid treatment unit is removed, the valve mechanism is
automatically shifted to its out-of-service position so as to shut
off the passage between the inlet port and the discharge port. The
passage between the return port and the outlet port is also
preferably shut off. In addition, the valve mechanism preferably
opens a bypass passage between the inlet and outlet ports so that
the flow of the fluid through the supply system will not be
interrupted. When the fluid treatment unit is mounted on the body,
the valve mechanism is automatically shifted to its normal service
position so as to close the bypass passage, while causing the fluid
to flow through the fluid treatment unit. The valve mechanism is
preferably operated by a tube or other element projecting from the
treatment unit and engageable with a movable component or member of
the valve mechanism. The treatment unit preferably comprises a
disposable element and a coupling element adapted to be interposed
between the disposable element and the valve body. In this way, the
cost of the disposable element is minimized. The coupling element
preferably comprises a tube having one portion adapted to extend
into the disposable element, and another portion adapted to extend
into the valve body so as to operate the valve mechanism.
Further objects, advantages and features of the present invention
will appear from the following description, taken with the
accompanying drawings, in which:
FIG. 1 is an elevational view showing a fluid treatment device to
be described as an illustrative embodiment of the present
invention.
FIG. 2 is an exploded or disassembled elevational view of the fluid
treatment device.
FIG. 3 is an enlarged longitudinal section taken through the valve
unit and the coupling element of the fluid treatment device.
FIG. 4 is a view similar to FIG. 3, but showing the valve unit and
the coupling element in their disassembled relation.
FIG. 5 is a cross section through the coupling unit, taken
generally along the line 5--5 in FIG. 4.
FIG. 6 is a view similar to FIG. 4 but showing a modified
construction.
FIG. 7 is an enlarged longitudinal section similar to FIG. 4, but
showing another modified construction in which the valve mechanism
includes an automatic bypass valve.
It will be seen that a fluid treatment device 10 is illustrated in
a general way in FIGS. 1 and 2. The illustrated device 10 comprises
a fluid treatment unit 12 which is adapted to be removably mounted
on a valve unit 14. Inlet and outlet pipes 16 and 18 may be
connected to the valve unit 14 to carry the fluid to and from the
valve unit. It will be understood that the valve unit 14 directs
the fluid through the fluid treatment unit 12, when it is mounted
on the valve unit 14.
The fluid treatment unit 12 is easily removable from the valve unit
14, and may also be easily replaced. To provide for quick and easy
renewal of the fluid treatment unit 12, it is preferred to make the
entire fluid treatment unit, or a readily removable component
thereof, disposable so that the old disposable unit or component
may be removed and replaced immediately with a new unit or
component, when the old unit or component has reached its limit of
usefulness or has ceased to function effectively. In this case, the
fluid treatment unit 12 comprises a disposable component or element
20 and a coupling component or element 22 adapted to be interposed
between the disposable element 20 and the valve unit 14. The
coupling component 22 is adapted to be removably mounted on the
valve unit 14, while the disposable component 20 is readily
removable from the coupling component 22. The provision of the
coupling component 22 minimizes the cost of the disposable
component 20.
The disposable component 20 may contain a filter medium, a
strainer, a water softening medium, or any other fluid treatment
medium. As illustrated, the disposable component 20 comprises a
canister 24 for holding the fluid treatment medium. The canister 24
may be made of sheet metal or some other suitable material.
Means are provided for removably mounting the fluid treatment unit
12 on the valve unit 14. As shown, the valve unit 14 comprises a
body 26 having a tubular member 28 formed with external screw
threads 30. The coupling component 22 of the fluid treatment unit
12 comprises a nut 32 having internal screw threads 34, adapted to
mate with the screw threads 30. Thus, the coupling component 22 may
simply be screwed onto the tubular member 28 of the valve body
26.
The disposable component 20 of the fluid treatment unit 12 is
adapted to be removably connected to the coupling component 22. As
shown, the coupling component 22 has an externally threaded tubular
member 36 extending axially from the nut 32. To mate with the
threaded member 36, the illustrated canister 24 is fitted with an
internally threaded ring or bushing 38 at its upper end.
The construction of the fluid treatment unit 12 may be varied
widely. In this case, the coupling component 22 comprises an axial
tube 40 having a lower portion 42 adapted to extend downwardly into
the disposable canister 24. The illustrated tube 40 has an upper
portion 44 adapted to project upwardly into the valve body 26. In
the usual arrangement, the tube 40 carries the fluid to the bottom
of the canister 24. The fluid then passes upwardly through the
fluid treatment medium in the canister 24. As shown, the tube 40
extends through and is mounted in a bushing 46 secured within the
nut 32. One or more openings 48 are formed in the bushing 46,
parallel to the tube 40, to carry the fluid out of the canister 24.
Six such openings 48 are illustrated in FIG. 5.
The details of the valve unit 14 are shown in FIGS. 3 and 4. Inlet
and outlet openings 50 and 52 are formed in the valve body 26. Such
openings 50 and 52 are preferably formed in tubular members 54 and
56 on the body 26. As shown, the inlet and outlet openings 50 and
52 are formed with internal threads 58 and 60 to receive the pipes
16 and 18.
The bushing 46 on the coupling unit 22 preferably comprises an
upper portion 62, adapted to be inserted into an opening 64 in the
tubular member 28. A seal is preferably provided between the
coupling component 22 and the tubular member 28. As shown, such
seal is provided by an O-ring 66 mounted on the upper portion 62 of
the bushing 46. The O-ring 66 is adapted to form a seal with the
bore or opening 64 in the valve body 26.
Generally speaking, the valve unit 24 is arranged to provide an
inlet passage whereby the fluid is carried between the inlet
opening 50 and the inlet opening of the removable fluid treatment
unit 12. In this case, the interior of the tube 40 provides the
latter inlet opening. The valve unit 24 also provides an outlet
passage whereby the fluid is carried between the removable fluid
treatment unit 12 and the outlet opening 52. In this case the
openings 48 serve as the outlets from the removable fluid treatment
unit 12.
A movable valve member 70 is provided within the valve body 26 to
close off the inlet passage between the inlet opening 50 and the
fluid treatment unit 12, when the treatment unit is removed from
the valve unit 24. Preferably, the valve member 70 also closes off
the outlet passage between the outlet opening 52 and the fluid
treatment unit 12. When the fluid treatment unit 12 is installed on
the valve unit 24, the valve member 70 is automatically moved to
its open position, so that both the outlet passage and the inlet
passage will be opened.
In this case, the movable valve member 70 is in the form of a
slidable piston or plunger having inlet and outlet stoppers or
plugs 72 and 74. It is preferred that the plugs 72 and 74 be faced
with rubber or some other soft resilient material. The inlet and
outlet plugs 72 and 74 are movable into engagement with seats 76
and 78. The seat 76 is formed on one end of a ring shaped member 80
which also serves as a guide for the valve member 70. Thus, the
valve member 70 has a cylindrical intermediate portion 82 which is
slidable within the seat member 80. An O-ring or some other seal 84
is preferably provided between the interior of the seat member 80
and the cylindrical portion 82 of the valve member 70. The opening
within the seat member 80 forms a portion of the inlet passage
between the inlet opening 50 and the fluid treatment unit 12. When
the plug member 72 is moved away from the seat 76, the fluid can
pass from the inlet opening 50 into a bore 90 within the valve
member 70, through one or more openings 92 formed in the wall of
the valve member 70, near the plug member 72. From the bore 90, the
fluid passes into the tube 40 on the fluid treatment unit 12. The
tube 40 carries the fluid into the disposable component 20 of the
fluid treatment unit 12.
When the fluid treatment unit 12 is mounted on the valve unit 14,
the tube 40 is inserted into the bore 90, as shown in FIG. 3. An
O-ring or some other seal 94 is preferably provided between the
bore 90 and the tube 40.
When the fluid treatment unit 12 is mounted on the valve unit 14,
the tube 40 engages the valve member 70 and moves it to its open
position, as shown in FIG. 3. In this case, the end of the tube 40
is engageable with a shoulder 96 within the bore 90.
It will be seen that the tubular seat member 80 is mounted in the
valve body 26 so as to extend through a partition wall 98 between
the inlet and outlet openings 50 and 52. The axis of the seat
member 80 preferably coincides with the axis of the bore 64 within
the tubular member 28, on which the fluid treatment unit 12 is
mounted.
Means are preferably provided to bias the valve member 70 towards
its closed position. As illustrated, such means comprise a spring
100 engaging the valve member 70 and received within a tubular
member 102 on the valve body 26. A plug 104 is screwed into the
tubular member 102 to retain the spring 100. An O-ring 106 or some
other seal is preferably provided between the plug 104 and the
tubular member 102.
As illustrated, the outlet seat 78 is formed on one end of a ring
shaped seat member 108 which is mounted within the bore 64. The
seat member 108 has an opening 110 therein which serves as a
portion of the outlet passage between the outlet opening 52 and the
fluid treatment unit 12. When the valve member 70 is in its closed
position, the plug member 74 closes the bore 110 so that the fluid
in the outlet opening 52 cannot escape through the bore 110. When
the valve member 70 is moved to its open position by insertion of
the tube 40, as shown in FIG. 3, the fluid can pass into the outlet
opening 52 from the fluid treatment unit 12, through the openings
48, the bore 64 and the bore 110.
It may be helpful to summarize the operation of the illustrative
fluid treatment device 10 shown in FIGS. 1-5. When the fluid
treatment unit 12 requires replacement, because it has lost
efficiency or has been in service for its normal, useful life, the
fluid treatment unit 12 is removed from the valve unit 14. This is
easily done by unscrewing the nut 32 from the valve body 26. As the
upper portion 44 of the tube 40 is withdrawn from the valve member
70, the spring 100 moves the valve member 70 to its closed
position, in which the plug members 72 and 74 engage the seats 76
and 78. As a result, the fluid cannot escape from the inlet opening
50 into the bore 90 within the valve member 70. Accordingly, the
fluid pressure within the inlet opening 50 is maintained, and no
substantial discharge of the fluid takes place. The outlet plug 74
closes the bore 110 in the seat member 108 so that the fluid in the
outlet opening 52 cannot escape out of the valve unit 14 through
the bore 64. Only the small amount of fluid already in the bore 64
is discharged, so that no significant amount of fluid is lost or
spilled.
The disposable component 20 of the fluid treatment unit 12 can be
unscrewed from the coupling component 22, so that the disposable
component can be discarded. A new disposable component is then
screwed onto the coupling component 22. By making the disposable
component and the coupling component separately, the cost of the
disposable component can be minimized. However, thse components can
be combined into one unitary assembly, if desired.
The entire fluid treatment unit 12 is then screwed onto the tubular
member 28 on the valve body 26. In the process, the upper end 44 of
the tube 40 is inserted into the bore 90 in the valve member 70.
The O-ring 94 forms a seal around the tube 40. Simultaneously, the
upper portion 62 of the bushing 46 is inserted into the bore 64 in
the valve body 26. The O-ring 66 forms a seal around the member
62.
As the nut 32 is screwed onto the threads 30 on the tubular member
28, the upper end 44 of the tube 40 engages the shoulder 96 in the
valve member 70 so that the valve member is moved to its open
position, as shown in FIG. 3. The fluid under pressure then flows
from the inlet opening 50 through the holes 92 in the valve member
70, and then into the tube 40, which carries the fluid into the
disposable component 20 of the fluid treatment unit 12. The fluid
is treated by the filter medium or some other fluid treatment
medium in the disposable component 20.
The fluid passes out of the disposable component 20 through the
openings 48, and then through the bore 110 in the seat member 108,
into the outlet opening 52.
FIG. 6 illustrates a modified valve unit 114 having a movable valve
member 116 with only one plug member 118, adapted to close the
inlet passage between the inlet opening 50 and the removable fluid
treatment unit 12. Thus, the plug member 118 is engageable with a
seat 120 formed on one end of a tubular seat member 122, extending
through the partition wall 98. As before, the movable valve member
116 is biased toward the seta 120 by the spring 100.
The tube 40 on the removable treatment unit 12 is adapted to be
inserted into a bore 124 formed in the tubular seat member 122. An
O-ring 126 or some other seal is mounted within the bore 124 to
form a seal around the tube 40. In this case, the tube 40 directly
engages the plug element 118 on the valve member 116 so as to move
the valve member to its open position. One or more openings 127 are
formed in the wall of the tube 40 at its upper end so that the
fluid can flow into the tube 40 from the inlet opening 50 when the
plug member 118 is unseated.
When the treatment unit 12 is removed from the valve unit 114, the
valve member 116 prevents any significant loss of the fluid from
the inlet opening 50. A small amount of fluid may be lost from the
outlet opening 52, which is not shut off, but in many cases this
small amount of fluid can easily be collected in a suitable
container. The modified construction of FIG. 6 is particularly
applicable to situations in which little or not fluid pressure
exists in the outlet opening 52 when the fluid treatment unit 12 is
removed.
FIG. 7 illustrates another modified fluid treatment device 130
which is similar in many respects to the fluid treatment device 10
of FIGS. 1-5. Insofar as the fluid treatment device 130 is the same
as previously described, the same reference characters have been
used in FIG. 7 as in FIGS. 1-5. Thus, it will suffice to describe
the differences between the fluid treatment device 130 and the
device 10 of FIGS. 1-5.
Generally, the fluid treatment device 130 differs from the devices
previously described in that the fluid treatment device 130
provides a bypass passage 132 between the inlet and outlet openings
or ports 50 and 52. During normal service, when the fluid treatment
unit 12 is mounted on the device 130, the bypass passage 132 is
closed by the automatic valve mechanism in the device 130. When the
fluid treatment unit 12 is removed from the treatment device 130,
the automatic valve mechanism opens the bypass passage 132 so that
the fluid can flow between the inlet and outlet ports 50 and 52.
This arrangement obviates any interruption in the flow of the fluid
due to the removal of the fluid treatment unit 12.
It will be seen from FIG. 7 that the fluid treatment device 130 has
a valve body 134 which is modified to provide the bypass passage
132. The body 134 contains an automatic valve mechanism 136 which
is modified in that the movable valve member 70, previously
described, is replaced with a movable valve member 138 having an
additional plug member or poppet 140 adapted to close the bypass
passage 132 when the valve member 138 is in its normal service
position. The plug member 140 may be formed integrally with the
movable valve member 138. As shown, the plug member 140 constitutes
an axial extension of the plug member 72, but faces in the opposite
direction.
As shown, both plug members 72 and 140 are movable axially along a
bore 142 formed in the valve body 134. The bore 142 provides a
portion of the bypass passage 132. Preferably, there is ample
clearance between the plug member 140 and the bore 142 so that the
fluid can flow along the space between the plug and the bore.
The illustrated plug member 140 is adapted to seal against an
annular seat member 144 which is suitably secured within the bore
142. The seat member 144 is formed with an axial opening 146 which
is adapted to be closed by the plug member 140.
As shown, the lower end of the bore 142 communicates with the inlet
opening 50 so that the fluid can flow through the opening 50 and
the bore 142 to the lower side of the seat member 144. If desired,
an additional passage 148 may be formed in the body 134 between the
inlet opening 50 and the bore 142 at a point just below the seat
member 144. It will be evident that the passage 148 forms a portion
of the bypass passage 132.
The bore 142 has a portion 150 which continues above the seat
member 144. A passage 152 is preferably formed in the valve body
134 between the bore 150 and the outlet opening or port 52. It will
be evident that the passage 152 forms a portion of the bypass
passage 132.
The fluid treatment device 130 has a modified spring arrangement
for biasing the movable valve member 138 towards its out-of-service
position. Such spring arrangement may comprise a modified spring
154 which is compressed between the plug 104 and a member 156 which
is movable with the valve member 138. As shown, the member 156 is
movable axially along the bore 150. The member 156 has a shank 158
of reduced diameter which extends through the axial opening 146 in
the seat member 144. The shank 158 is suitably connected to the
movable valve member 138. As shown, the shank 158 is securely
fitted into an axial opening 160 in the plug member 140.
It may be helpful to summarize the operation of the fluid treatment
device 130 of FIG. 7. As shown, the treatment device 130 is in its
out-of-service position inasmuch as the removable treatment unit 12
is detached from the valve body 134. It will be seen that the plug
member or poppet 72 prevents any flow of the fluid between the
inlet port 50 and the discharge opening or port 90. Thus, no fluid
is allowed to escape from the fluid treatment device 130.
Similarly, the valve plug or poppet 74 is engaged with the seat 78
so as to prevent any fluid from passing from the outlet port 52 to
the return port or opening 110.
On the other hand, the plug member or poppet 140 is out of
engagement with the seat member 144 so that fluid can flow through
the bypass passage 132 between the inlet and outlet ports 50 and
52. The bypass passage 132 comprises several portions and may be
traced through the passage 148, the bore 142, the opening 146, the
bore 150 and the passage 152.
The fluid treatment unit 12 is mounted on the valve body 134 in the
same manner as previously described. Thus, the upper portion 44 of
the central tube 40 is inserted into the discharge port 90 in the
valve member 138. The O-ring 94 forms a seal around the tube 40.
The upper portion 62 of the bushing 46 is inserted into the return
port 64. The O-ring 66 forms a seal therebetween. The internal
threads 34 on the nut 32 are engaged with the external threads 30
on the valve body 134.
The valve member 138 is actuated by the upper end tube portion 44
which engages the shoulder 96 and pushes the valve member 138
upwardly against the resilient resistance of the spring 154. The
movement of the valve member 138 brings the valve plug or poppet
140 against the seat member 144 so that the poppet closes the
opening 146. In this way, the bypass passage 132 is automatically
closed. The poppets 72 and 74 are moved away from the seats 76 and
78. Thus, the fluid is caused to flow through the removable fluid
treatment unit 12. The fluid passes from the inlet opening 50
through the radial openings 92 and into the discharge port or
opening 90 within the valve member 138. From the opening 90, the
fluid flows within the tube 40 into the disposable fluid treatment
element 20. In returning from the fluid treatment element 20, the
fluid passes through the openings 48 into the return port 64 and
then through the opening 110 in the seat member 108. The fluid then
passes out of the fluid treatment device 130 through the outlet
port 52.
When the fluid treatment unit 12 is removed from the valve body
134, the downward movement of the upper tube portion 44 allows the
valve member 138 to be moved downwardly by the force of the spring
154. The poppets or plugs 72 and 74 engage the seats 76 and 78
before the upper tube portion 44 is withdrawn from the O-ring 94,
and also before the O-ring 66 is moved out of the port 64. Thus, no
significant amount of fluid escapes. The bypass passage 132 is
again opened by the movement of the poppet 140 away from the seat
member 144.
* * * * *