U.S. patent application number 10/991797 was filed with the patent office on 2006-05-18 for liquid dispenser with sealing module.
Invention is credited to Gregory A. Balnoschan, Bryan W. Clever, Timothy M. Garrison.
Application Number | 20060102246 10/991797 |
Document ID | / |
Family ID | 36384926 |
Filed Date | 2006-05-18 |
United States Patent
Application |
20060102246 |
Kind Code |
A1 |
Clever; Bryan W. ; et
al. |
May 18, 2006 |
Liquid dispenser with sealing module
Abstract
A sliding stem seal assembly for a fluid dispenser. In one
embodiment, an insertable module retains a stem seal and a housing
seal even when disengaged from the housing of the dispenser. The
module isolates the stem seal from the housing such that it
contacts the stem and a low friction surface of the module, and the
module also isolates the housing seal from movement of the stem,
for reduced wear from the housing and the moving stem.
Inventors: |
Clever; Bryan W.; (Liberty
Township, OH) ; Garrison; Timothy M.; (Cincinnati,
OH) ; Balnoschan; Gregory A.; (Powell, OH) |
Correspondence
Address: |
DINSMORE & SHOHL, LLP
1900 CHEMED CENTER
255 EAST FIFTH STREET
CINCINNATI
OH
45202
US
|
Family ID: |
36384926 |
Appl. No.: |
10/991797 |
Filed: |
November 18, 2004 |
Current U.S.
Class: |
141/206 |
Current CPC
Class: |
B67D 7/48 20130101 |
Class at
Publication: |
141/206 |
International
Class: |
B65B 1/30 20060101
B65B001/30 |
Claims
1. A fluid dispenser comprising: a fluid dispenser housing
comprising an inner chamber defined by a chamber surface; a
cylindrical stem including an outer surface, said stem being
configured to control the flow of fluid through said housing; an
insertable module selectively engaged with said inner chamber and
including an opening slidingly receiving said stem; a stem seal
member retained by said module and in sealing contact with said
outer surface of said cylindrical stem when said module is engaged
with said inner chamber to provide a first seal, wherein said stem
seal member is separated from said housing by a portion of the
module and wherein said stem seal member contacts said stem and a
substantially non-porous portion of said module; and a housing seal
member retained by said module and in sealing contact with said
chamber surface of said housing when said module is engaged with
said inner chamber to provide a second seal, wherein said housing
seal member is separated from said stem by a portion of said module
whereby said second seal provides a static seal against said
chamber surface; wherein said module is configured to retain said
stem seal member and said housing seal member when said module is
disengaged from said chamber.
2. The dispenser as recited in claim 1, wherein said stem seal
member comprises at least one flange and includes an internal
energizing member.
3. The dispenser as recited in claim 2, wherein said flange
contacts said outer surface of said stem to provide a lip-like seal
when said module engages said inner chamber.
4. The dispenser as recited in claim 1, wherein said module
includes a first recess for retaining said stem seal member and a
second recess for retaining said housing seal member.
5. The dispenser as recited in claim 1, wherein said module
threadably engages said housing chamber.
6. The dispenser as recited in claim 1, wherein said module
comprises at least two engaged members.
7. The dispenser as recited in claim 6, wherein said stem seal
member is retained between said engaged members.
8. The dispenser as recited in claim 1, wherein said housing seal
member comprises at least one O-ring.
9. The dispenser as recited in claim 8, wherein said O-ring
contacts said chamber surface of said housing to provide a
ring-like seal in use.
10. A fluid dispensing assembly comprising: a main body including
an inlet port adapted to communicate with a source of pressurized
fluid and an outlet port adapted to dispense fluid from said main
body, wherein said main body includes an inner chamber defined by a
chamber surface; a stem including an outer surface, wherein said
stem is adapted to assist in regulating fluid between said inlet
port and said outlet port of said main body a stem seal including
an opening slidably receiving said stem and comprising an inner
sealing surface, wherein said inner sealing surface sealingly
contacts said outer surface of said stem to provide a first seal; a
body seal sealingly contacting said chamber surface of said body to
provide a second seal; a module configured to selectively engage
said inner chamber and including an opening for receiving said
stem, wherein said module is adapted to retain said stem seal and
said body seal when said module is disengaged from said chamber,
and wherein said stem seal provides said first seal against said
stem when said module engages said inner chamber and wherein said
body seal provides said second seal against said chamber surface
when said module engages said inner chamber; and a manual actuator
adapted to control movement of said stem and control the flow of
fluid through said main body.
11. The assembly as recited in claim 10, wherein said stem seal is
isolated from the main body and is held between said stem and a
substantially smooth surface of said module.
12. The assembly as recited in claim 10, wherein said stem seal
includes at least one flange, and wherein said stem seal comprises
a Teflon material and includes an energizing member included within
said stem seal.
13. The assembly as recited in claim 10, wherein said module
includes at least two engaged pieces.
14. The assembly as recited in claim 10, wherein said module
includes a first void for retaining said stem seal and a second
void for retaining said body seal.
15. The assembly as recited in claim 10, wherein said body seal is
isolated from movement of said stem, and wherein said stem seal is
isolated from said body.
16. The assembly as recited in claim 10, further comprising a
shut-off actuator configured to automatically shut off flow of
fluid through said main body in response to a fill condition.
17. A fuel dispenser comprising: a main body including an inlet
port adapted to communicate with a source of pressurized fuel and
an outlet port adapted to dispense fuel from said main body,
wherein said main body includes an inner chamber defined by a
chamber surface; a seal comprising a sealing surface, wherein said
sealing surface sealingly contacts a component of said fuel
dispensing assembly to provide a first seal; an insertable retainer
configured to selectively engage said inner chamber, wherein said
retainer is adapted to retain said seal when said retainer is
disengaged from said chamber, and wherein said seal provides said
first seal against said assembly component when said retainer
engages said inner chamber; a manual actuator adapted to control
the flow of fuel through said main body; and a shut-off actuator
configured to automatically shut off flow of fuel through said main
body in response to a fill condition.
18. The fuel dispenser as recited in claim 17, wherein said seal is
isolated from said main body and is held between said component and
a low friction surface of said retainer.
19. The fuel dispenser as recited in claim 17, wherein said
component comprises a moving component separate from said main
body, and wherein said dispenser further comprises a second seal
retained by said retainer and isolated from said moving component,
wherein said second seal contacts said main body and wherein said
first seal is isolated from said main body by said retainer.
20. A method for assembling a fuel dispensing apparatus, the method
comprising: placing a seal on a module such that said seal is held
on said module; providing components for assembling a fuel
dispensing apparatus; engaging said module with a housing for a
fuel dispensing apparatus, such that said seal contacts at least
one of said housing and said components and provides a fluid-tight
seal therewith; and assembling said components and said housing as
a fuel dispensing apparatus.
21. The method as recited in claim 20, wherein said module engages
said housing by a threaded engagement, and wherein said seal is
placed within a recess of said module.
22. The method as recited in claim 20, wherein said seal comprises
a poppet stem seal, wherein one of said components comprises a
poppet stem, and wherein the method further comprises: placing said
poppet stem through said module and said seal.
23. The method as recited in claim 20, wherein one of said
components comprises a poppet stem and wherein said seal contacts
said poppet stem and is isolated from said housing by said module,
and wherein said method further comprises: placing a second seal on
said module whereby said second seal is isolated from said poppet
stem by said module, and wherein said second seal sealingly
contacts said housing upon engaging said module with said
housing.
24. The method as recited in claim 20, further comprising: engaging
a first piece of said module with a second piece of said module
such that said seal is held between said two pieces.
25. A fluid dispenser comprising: a fluid dispenser housing
comprising an inner chamber defined by a chamber surface; a poppet
stem assembly residing within the inner chamber and comprising: a
cylindrical stem including an outer surface, said stem being
configured to control the flow of fluid through said housing; a
stem seal member in sealing contact with said outer surface of said
cylindrical stem to provide a first seal, wherein said stem seal
member does not contact said housing; and a housing seal member in
sealing contact with said chamber surface of said housing to
provide a second seal, wherein said housing seal member does not
contact said stem.
26. The dispenser as recited in claim 25, wherein said stem seal
member is located between a low friction surface and said stem.
27. The dispenser as recited in claim 25, wherein said stem seal
member and said housing seal member are retained by an insertable
module.
Description
RELATED APPLICATION
[0001] This application is related to U.S. patent application Ser.
No. ______ (Attorney Docket No. 3356-179) filed on Nov. 18, 2004,
entitled Liquid Dispenser with Stem Sealing System, the entire
disclosure of which is hereby incorporated herein by reference.
TECHNICAL FIELD
[0002] This invention relates generally to liquid dispensing
devices, and more particularly to seal assemblies for liquid
dispensing devices.
BACKGROUND OF THE INVENTION
[0003] Fluid dispensers include a variety of components for
selectively controlling the flow of and dispensing a fluid. Fuel
dispensing systems can include, for example, a stem for assisting
in actuating a poppet valve between opened and closed positions to
control fluid flow between an inlet and outlet port. For instance,
a fluid dispensing system is described in U.S. Pat. No. 3,811,486
(the '486 Patent) to Wood, the entire disclosure of which is hereby
incorporated herein by reference.
[0004] Fluid dispensing assemblies or nozzles can comprise a main
body with an inlet port adapted to communicate with a source of
pressurized fluid, and an outlet port adapted to dispense fluid
from the main body. In such devices, a stem, for actuating a valve,
slides relative to a seal or to a packing (typically loose material
stuffed around the stem in a chamber). As described in further
detail in the referenced '486 patent, the stem, together with a
lever, can assist in actuating the valve, such as a poppet valve,
to control fluid dispensing.
[0005] Typically, the packing, an O-ring or a related flanged lip
seal has been provided to prevent leakage of fluid along the stem,
and more particularly between the stem and portions of the main
body. In some devices, a flanged lip seal with an internal O-ring
energizer has been utilized.
[0006] However, such seals and sealing systems have exhibited
problems with respect to sealing performance and/or durability. For
example, such seals may exhibit rapid deterioration and wear from
movement within the dispenser. Accordingly, the seal can become
quickly compromised, resulting in leakage of the fluid. In
addition, such seals typically have an inner surface which seals
against the moving stem, or other component, and an outer surface
which seals against the stationary dispenser body. Friction from
movement of the seal caused by movement of the stem can compromise
the sealing surface against the stem as well as the sealing surface
against the stationary body.
[0007] In addition, inserting a seal into a dispensing device can
be time consuming and tedious. The seal is typically small and
required to be fitted within a narrow chamber. Often, specialized
tools are required to compress the seal and place it into the
housing of the dispenser against the components being sealed.
SUMMARY OF THE INVENTION
[0008] Accordingly, it is desired to obviate problems and
shortcomings of conventional seal assemblies. More particularly, in
some embodiments, it is desired to provide improvements in
durability and/or performance of seals in fluid dispensing
apparatus. Moreover, in some embodiments, it is desired to reduce
the difficulty and minimize the time needed for assembling a fluid
dispensing apparatus.
[0009] According to one aspect, a fluid dispenser is provided
comprising a fluid dispenser housing having an inner chamber
defined by a chamber surface, and a cylindrical stem that includes
an outer surface. The stem is configured to control the flow of
fluid through said housing. The dispenser also includes an
insertable module which is selectively engaged with said inner
chamber and includes an opening slidingly receiving said stem. A
stem seal member is retained by said module and is in sealing
contact with the outer surface of the cylindrical stem when the
module is engaged with the inner chamber to provide a first seal.
The stem seal member is separated from the housing by a portion of
the module and the said stem seal member contacts the stem and a
substantially non-porous portion of said module. The assembly also
includes a housing seal member retained by the module and in
sealing contact with the chamber surface of the housing when the
module is engaged with the inner chamber to provide a second seal.
The housing seal member is separated from the stem by a portion of
the module whereby the second seal provides a static seal against
the chamber surface. The module is configured to retain the stem
seal member and the housing seal member when the module is
disengaged from the chamber.
[0010] According to another aspect, a fluid dispensing assembly is
provided comprising a main body including an inlet port adapted to
communicate with a source of pressurized fluid and an outlet port
adapted to dispense fluid from said main body, the main body
including an inner chamber defined by a chamber surface. The
assembly also includes a stem having an outer surface, wherein the
stem is adapted to assist in regulating fluid between said inlet
port and said outlet port of said main body. In addition, the
assembly includes a stem seal having an opening slidably receiving
the stem and comprising an inner sealing surface, wherein the inner
sealing surface sealingly contacts the outer surface of the stem to
provide a first seal. In addition, the assembly includes a body
seal sealingly contacting the chamber surface of the body to
provide a second seal, and a module configured to selectively
engage the inner chamber and including an opening for receiving the
stem. The module is adapted to retain the stem seal and the body
seal when the module is disengaged from the chamber. The stem seal
provides the first seal against the stem when the module engages
the inner chamber and the body seal provides the second seal
against the chamber surface when the module engages the inner
chamber. The assembly further includes a manual actuator adapted to
control movement of the stem and control the flow of fluid through
the main body.
[0011] According to an additional aspect, a fluid dispenser is
provided comprising a main body including an inlet port adapted to
communicate with a source of pressurized fuel and an outlet port
adapted to dispense fuel from said main body, wherein said main
body includes an inner chamber defined by a chamber surface. The
dispenser also includes a seal having a sealing surface, wherein
the sealing surface sealingly contacts a component of the fuel
dispensing assembly to provide a first seal. The dispenser also
comprises an insertable retainer configured to selectively engage
the inner chamber, wherein the retainer is adapted to retain the
seal when the retainer is disengaged from said chamber, and wherein
the seal provides the first seal against the assembly component
when the retainer engages the inner chamber. The dispenser also
includes a manual actuator adapted to control the flow of fuel
through the main body, and a shut-off actuator configured to
automatically shut off flow of fuel through the main body in
response to a fill condition.
[0012] According to another aspect, a method for assembling a fuel
dispensing apparatus is provided, the method comprising placing a
seal on a module such that the seal is held on said module, and
providing components for assembling a fuel dispensing apparatus.
The method also comprises engaging the module with a housing for a
fuel dispensing apparatus, such that the seal contacts at least one
of the housing and the components and provides a fluid-tight seal
therewith. The method further comprises assembling the components
and the housing as a fuel dispensing apparatus.
[0013] In accordance with another aspect, a fluid dispenser is
provided comprising a fluid dispenser housing having an inner
chamber defined by a chamber surface, and a poppet stem assembly
residing within the inner chamber. The poppet stem assembly
comprises a cylindrical stem including an outer surface, the stem
being configured to control the flow of fluid through the housing.
The assembly also includes a stem seal member in sealing contact
with the outer surface of said cylindrical stem to provide a first
seal, wherein the stem seal member does not contact said housing.
In addition, the assembly includes a housing seal member in sealing
contact with the chamber surface of the housing to provide a second
seal, wherein the housing seal member does not contact the
stem.
[0014] Still other aspects of the present invention will become
apparent to those skilled in the art from the following description
wherein there are shown and described alternative illustrative
embodiments including inventive aspect. These embodiments and
descriptions are provided only as illustrative examples, and in no
way are intended, nor should they be interpreted, as limiting. As
will be realized, the invention is capable of other different
embodiments, all without departing from the scope of the invention.
These other possible embodiments will be understood by those
skilled in the art based upon the description and teachings herein.
Accordingly, the drawings and descriptions should be regarded as
illustrative and exemplary in nature only, and not as
restrictive.
BRIEF DESCRIPTION OF THE DRAWINGS
[0015] While the specification concludes with claims particularly
pointing out and distinctly claiming the inventive aspects, it is
believed the same will be better understood from the following
description taken in conjunction with the accompanying drawings in
which:
[0016] FIG. 1 is a partial sectional view of an illustrative
embodiment of a fluid dispensing assembly, made and operating in
accordance with principles of the present invention;
[0017] FIG. 2a is a cross sectional view of an illustrative
embodiment of a poppet stem seal module, made and operating
according to principles of the present invention;
[0018] FIG. 2b is a perspective view of the module of FIG. 2a;
[0019] FIG. 3a is a cross sectional view of an illustrative
embodiment of a seal that can be used in the stem seal module of
FIGS. 1 and 2, in accordance with principles of the present
invention;
[0020] FIG. 3b is a top view of the seal of FIG. 3a;
[0021] FIG. 4a is a perspective view of an illustrative embodiment
of the cantilever spring of the seal of FIGS. 3a and 3b;
[0022] FIG. 4b is a perspective view of the seal of FIGS. 3a and
3b;
[0023] FIG. 5 is a partial sectional view of another illustrative
embodiment of a fluid dispensing assembly, made and operating in
accordance with principles of the present invention;
[0024] FIG. 6 is a cross sectional view of an illustrative
embodiment of a fueling nozzle which includes the insertable poppet
stem seal module of FIG. 2, and which is made and operating
according to principles of the present invention; and
[0025] FIG. 7 is a cross sectional view of an illustrative
embodiment of a fueling nozzle which includes the insertable poppet
stem seal module of FIG. 5, and which is made and operating
according to principles of the present invention.
DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS
[0026] FIG. 1 depicts a fluid dispensing assembly 10, made and
operating in accordance with principles of the present invention.
The fluid dispensing assembly 10 includes a main body 12 with an
inlet port 14 adapted to communicate with a source of pressurized
fluid. For instance, in fuel dispensing applications, a high
pressure fuel hose can be removably connected to the inlet port 14
to allow a fuel pump (not shown) such as in a gasoline station to
act as a source of pressurized fuel for the fuel nozzle 10. The
fluid dispensing assembly 10 further includes an outlet port 16
adapted to dispense fluid from the main body 12. In fuel dispensing
applications, the outlet port 16 can take the form of a familiar
spout or other device adapted to communicate with the inlet opening
of a vehicle fuel tank.
[0027] As further illustrated in FIG. 1, the fluid dispensing
assembly 10 may include a sliding stem seal assembly 18, wherein a
stem 20 may axially reciprocate relative to a stem seal member 50
as discussed more fully below. The stem 20 is adapted to assist in
regulating fluid between the inlet port 14 and the outlet port 16.
For example, as illustrated in FIG. 1, the stem 20 can assist in
actuating a valve, such as a poppet valve 26. In order to dispense
fluid, an operator will move the actuator, such as lever 13, and
the stem 20 therewith, upwardly relative to the main body 12 to
open the valve 26. When the stem 20 moves back downwardly, such as
under a bias force, the valve 26 closes. To reduce wear and
friction between the stem 20 and the lever 13, the stem 20 may be
provided with an optional wear resistant tip 24 made from a
material with a relatively low coefficient of friction.
[0028] In this embodiment, the seal 50 is retained by an insertable
and removable module 28, according to principles of the present
invention. The module 28 can be selectively engaged with the main
body 12, such as via threads or other suitable engagement methods.
The module 28 can include multiple components for retaining and
holding the seal 50, which provides a seal against the stem 20. The
module 28 holds the seal 50 even when the module is disengaged from
the main body 12. In this embodiment, module 28 also retains a seal
48 which provides a seal against the main body 12. As will be
discussed in more detail below, the module 28 of this embodiment
can provide improved sealing performance and durability, as well as
increase the ease of assembling the components of the stem seal
assembly 18.
[0029] The removable seal module 28 of this embodiment is shown in
more detail in FIG. 2 (comprising FIGS. 2a and 2b). As shown, this
embodiment of the module 28 includes a stainless steel sleeve 30
having an internal passage 32 for slidingly receiving the stem 20.
The passage 32 includes a wide passage portion 31 at the upper end
of the sleeve 30, which transitions to a narrow passage portion 33.
The module 28 also includes a bushing 34 which is engaged within
the wide passage portion 31 of the sleeve 30. The bushing 34 can be
made from a plastic or other suitable low friction material, such
as a DELRIN material for example. The bushing 34 can therefore be
used, if desired, to reduce friction against the stem 20 as it
moves axially within the module 28.
[0030] The module 28 retains one or more seals for use in the
poppet valve stem seal assembly. In particular, in this embodiment,
the sleeve 30 includes recesses or voids for placement of two seals
which resists leakage of fuel as it flows through the dispenser. In
this example, a first recess comprises a groove 36 formed in the
exterior of the sleeve 30. Within the groove 36 is held a housing
seal member 48 to thereby retain the seal 48 within the module 28
when it is disengaged from the main body/housing 12 (FIG. 1).
However, when the module 28 is inserted into the housing 12, the
seal 48 abuts the housing 12 to provide a fluid tight seal
therewith to resist the leakage of fluid along the interface
between the module 28 and the housing 12. The seal 48 can comprise
a ring-like or other appropriate seal member, such as an O-ring
made from a nitrile (e.g., Buna) material for instance.
[0031] In addition, the module 28 retains (e.g., houses) a second
seal 50 for providing a seal against the stem 20. Accordingly, this
seal 50 is likewise retained by the module 28 prior to the module
being engaged with the housing 12. In particular, in this
embodiment, the sleeve 30 includes a recess 37 at one end, formed
by a narrow wall portion 39 and an interior seat 38. Accordingly,
the ring-like seal 50 resides within the recess 37 and against the
seat 38, with the narrow wall 39 surrounding the seal.
[0032] The module 28 can further include a guide or cap 42, for
additional support in retaining the seal 50. In particular, in this
embodiment, the diameter of the end portion 43 of the guide 42 is
approximately the same as the inner diameter of the recess 37
between walls 39. Accordingly, an interference fit or engagement is
provided between the end portion 43 of the guide 42 and the recess
37 of the sleeve. Guide 42 can likewise be made of a friction
reducing material, such as DELRIN for example. An extension 41 from
the guide 42 can be provided as stop to abut the wall 39 when the
guide 42 is engaged with the sleeve 30.
[0033] Accordingly, with reference to FIGS. 1-2, seal 50 is held
within two nested components (42 and 30) of the module 28, in this
embodiment. By tightly containing the seal 50 within the module 28
according to principles of the present invention, less movement of
the seal 50 results when the stem 20 axially slides against the
seal 50 during use. Accordingly, better performance and durability
can result. In addition, in this embodiment, a separate seal 48 is
provided to seal against the housing 12 of the dispenser. Seal 48
does not also seal against the stem 20, decreasing its potential
for any appreciable movement caused by the stem. Likewise, seal 50
does not seal against the porous housing, decreasing the potential
for seal 50 to fail. In particular, it has been found that
placement of a poppet stem seal 50 against a housing 12 can
gradually wear the finish of the housing, as the seal moves
slightly in response to movement of the stem 20, exposing the
porous material of the housing. The friction between the porous
housing material and the seal 50 can then quickly deteriorate the
seal. In this embodiment, however, the seal 50 is isolated from and
does not contact the housing 12, but rather contacts walls 39 of
the sleeve 30, which, according to additional aspects, can be made
from a low friction, smooth, and/or non-porous material, such as
stainless steel for example. Because the sliding stem seal 50
contacts this material rather than the housing, it has been found
to exhibit improved durability, even though the seal may move
slightly within the module 28 as the stem 20 slides against the
seal. In addition, because seal 48 is isolated from movement of the
stem 20 and does not contact the stem, it does not experience
appreciable movement and therefore does not experience frictional
wear against the porous housing 12.
[0034] To assemble the module 28, seal 48 can be slided over the
exterior surface of the sleeve 30 until it rests in groove 36. The
bushing 34 is placed into the chamber until it reaches the narrow
passage 33 such that it abuts and mates with the sleeve 30. Seal 50
can be placed into recess 37, and guide 42 can be pressed into the
recess 37 until extension 41 reaches and is stopped by the bottom
wall 39. Accordingly, the module 28 is ready to receive the stem 20
and to be engaged with the housing 12. Thus, the seals 48 and 50
are assembled with and retained by the module when it is disengaged
from the fluid dispenser housing 12, and can be later placed into
the fluid dispenser without the need for special tools and without
requiring difficult placements of small parts. Rather, the entire
module 28 can be placed into the housing 12 as a complete unit,
such as by engaging threaded portion 35 with a corresponding
threaded portion 15 within the housing 12 (See FIG. 1). The stem 20
can be placed through the center of the sleeve 30, and its interior
bushing 34 and seal 50, as well as through the center of the guide
42 engaged with the sleeve 30. All of these components in this
embodiment therefore have a passage through their center having a
diameter, at least at some portion, that is approximately the same
as or slightly larger than the diameter 21 of the stem 20.
Accordingly, stem 20 slides axially through the center of the
module 28. The seal 50 in this example also includes a flared end
such that its opening near that end is slightly smaller in diameter
than the diameter 21 of the stem 20. Accordingly, after the stem 20
is inserted through the module 28, the flared end of the seal 50
compresses somewhat between circular wall 39 and the exterior
surface of the stem 20, providing a fluid resistant seal at the
point of compression.
[0035] More specifically, as best seen in FIGS. 2-4, the seal 50
can include a base 56 and a flared end 51 with an inner flange 52
and an outer flange 54. Inner flange 52 flares radially toward the
stem 20 (i.e., in a generally inward direction) while the outer
flange 54 flares radially away from the stem 20 (i.e., in a
generally outward direction). In one embodiment, the seal 50 is
arranged such that the inner flange 52 contacts the outer surface
22 of the stem 20 to create a seal therewith along a
circumferential contact surface, edge or lip 64. Because the stem
20 is round in this embodiment, the inner flange 52 provides a
first or inner ring-like seal at the contact surface, edge or lip
64. In use, the inner flange 52 is deflected slightly inward such
that a relatively small portion of the inner flange 52 is in at
least partially compressed contact with the outer stem surface 22.
Providing a smaller area of contact lowers the friction force
between the stem and seal in use, thereby improving the
functionality (e.g., ease of actuation and sliding, with superior
sealing) of the fluid dispensing assembly while preventing undue
wear of either the seal 50 or the stem 20.
[0036] The seal 50 can also be arranged such that the outer flange
54 contacts an inner surface of the module sleeve 30 to similarly
create a seal therewith. The outer flange 54 thus provides a second
or outer ring-like seal adjacent the inner surface of the sleeve.
In certain embodiments of the present invention, and as illustrated
in FIG. 3b, the first ring-like seal can be at least substantially
concentric with the second ring-like seal, via surfaces 64 and
66.
[0037] The ring-like contact can be a knife-like contact (e.g.,
near surface, edge or lip 64, 66) or a limited vertical contact
surface. The seal 50 is thus provided in the shape of a torus or
general donut shape having an opening in the center (i.e., either
in the center or off-center depending upon the application) to
receive and sealingly engage the stem 20 in use.
[0038] With reference to FIGS. 1-4, and according to at least some
embodiments, the entire seal 50, or at least the outer surface of
the flared end 51 may be made of, or coated with, a material that
reduces the coefficient of friction, improves durability when
contacting fuel, and/or improves abrasion resistance of the seal.
For instance, the seal 50 may consist of entirely or essentially,
or partially comprise, a friction reducing material, such as a
fluorocarbon polymer for example. In particular,
polytetrafluoroethylene, fluorinated ethylene-propylene, ethylene
tetrafluoroethylene, or perfluoroalkoxy may be utilized, such as
those types of materials marketed under the trademark TEFLON.RTM.
(as available from E.I. DuPont de Nemours). As an alternative, high
performance friction reducing elastomers, such as POLYMOD.RTM. (as
available from Polymod Technologies, Inc.), could be utilized, as
could other friction reducing material compatible with the seal 50
and the application requirements. For example, elastomers which are
polymer modified to have very low coefficients of friction and
optimized wear life could also be utilized.
[0039] It has been found that particularly advantageous performance
and durability (with respect to friction characteristics, and
durability and size stability when in contact with fuel) can be
attained by constructing substantially the entire seal 50 using a
TEFLON material. In addition, the inner surface 74 of the sleeve 30
and/or the outer surface 22 of the stem 20 may be made of low
friction materials and/or appropriately finished or coated/treated
to further prevent undue friction and wear, and to optimize the
service life of the assembly. In one example of a fuel dispenser
nozzle stem, the outer surface 22 of the stem 20 may be optionally
finished with a finish of at least 12 for use with a seal 50 having
a TEFLON coating, or comprising or consisting of TEFLON. The
material used to construct the seal 50, partially or completely,
preferably results in a dynamic and/or static coefficient of
friction relative to the stem of less than about 0.1, such as less
than about 0.05 for example, which can result in improved
performance of the fueling nozzle. In particular, according to one
embodiment of the invention, using a seal made from TEFLON and a
stem made from stainless steel can provide a coefficient of
friction of the seal relative to the stem of about 0.04.
[0040] As shown in FIGS. 1-4, the seal 50 of at least some
embodiments embodiment can also be energized such that the flared
end 51 will include an appropriate positive or active outward
radial bias to provide sufficient pressure, and therefore provide a
sufficient fluid seal to minimize any potential for leakage along
the stem 20 and between the stem and the sleeve 30, when the nozzle
is in either a low-pressure mode or a zero-pressure mode. As used
herein, the term "energized" refers to any material, structure, or
combination of material and structures which tends to bias the
inner and outer flanges outwardly from the seal body so that, in
use, sealing contact can be positively or actively maintained even
where there are no fluid pressure forces compressing the seal. In
one example the flared end 51 of the seal 50 includes a recess 62
between the inner and outer flanges (as best shown in FIG. 4b).
Optionally providing the flared end 51 with a recess 62 permits the
flared end to expand under the influence of fluid pressure to allow
the outer surfaces of the flanges to also more efficiently seal as
fluid pressure increases.
[0041] In another example, the flared end 51 of this embodiment may
be energized by the choice of materials or other geometrical
characteristics of the flared end. In one example, the flared end
may be formed as a composite of different materials having
different properties.
[0042] In still further embodiments of the present invention, the
energizing of the flared end is achieved with an energizing member
60 as best shown in FIGS. 3-4. As illustrated, the energizing
member 60 can be at least partially located within the recess 62 of
the seal 50. It is understood that the energizing member 60 may
alternatively be substantially or entirely located within the
recess. Furthermore, the energizing member 60 may be encapsulated
within the flared end of the seal. For example, the energizing
member may be fabricated from a different material and then
embedded and concealed within the flared end.
[0043] Various types of energizing members 60 could be utilized.
For example, due to differing material properties, the energizing
member could then act to energize the flared end 51 of the seal. In
other examples, a wedge could be used as the energizing member to
cause the flanges to bias away from one another. In other examples,
the energizing member could take the form of a pressurized bladder,
an O-ring, or material compressed within the flared end of the
seal, or any material or component suitable to cause the flanges 52
and 54 to bias away from one another. With respect to other aspects
of the inventions, it will be understood that other shapes of
energizing members could be used such as energizing members with
square, rectangular, triangular, wedge-shaped, or other cross
sectional shapes, or that the energizing member could be removed.
Moreover, while a single energizing member is illustrated in the
embodiments, it is understood that a plurality of energizing
members could be provided, and that the energizing member need not
be unitary in nature. For example, a plurality of spaced, or
overlapping energizing members might be placed within a recess. For
instance, a plurality of O-rings could be stacked, one upon
another, or concentrically arranged. In addition, a plurality of
energizing members, such as spheres or ball bearings could be
radially arranged at least partially within the recess of the seal.
Similarly, it will be understood that the seal 50 could be formed
with a plurality of recesses that can each receive one or more
energizing members. With respect to some embodiments incorporating
aspects of the inventions, the energizing member could take other
forms, such as a hollow ring. In still other embodiments, the
energizing member may take the form of a coil spring, or similar
arrangement, connected end-to-end in the shape of a torus.
[0044] Returning to FIGS. 1-4, and in particular as best shown in
FIGS. 4a and 4b, in some embodiments it has been found advantageous
to use an energizing member 60 that takes the form of a
cantilevered spring. In particular, the figures depict the
energizing member 60 in the form of a cantilever spring, comprising
a plurality of fingers which serve to provide a force against the
seal 50, to improve sealing performance. FIGS. 3a, 3b, and 4b
illustrate the seal 50 and cantilever spring 60 of this embodiment
in more detail. FIG. 4a illustrates the cantilever spring 60,
without the seal 50 which retains the spring. As shown in these
figures, the spring 60 is disposed in the recess 62 of the seal 50,
and comprises a cantilever spring having a plurality of fingers 92.
Each of the fingers 92 runs between an inner wall 94 of the seal 50
and an outer wall 96 of the seal, the inner and outer walls
defining the recess of the open, hollow, donut-shaped seal 50.
Accordingly, the fingers 92 are each bent or otherwise disposed in
a general U-shape within the recess 62. To hold the fingers 92
within the seal 50, the seal can be provided with an inner top lip
98 and an outer top lip 99, such that the two ends 93 of each
finger 92 can be held under the respective inner surfaces 98' and
99' of these lips, and thereby be retained from exiting the open
end 51 of the seal 50. Alternatively, other structures can be
provided to hold the spring 60 within the seal 50.
[0045] In addition, in this embodiment, the fingers 92 are
connected at their ends 93, such as by an integral connection,
which allows the spring 60 to form a single continuous unit from
its two end points. By positioning and retaining the spring 60 in
the recess 62 in this manner, the fingers 92 of the spring provide
a substantially uniform or constant force or load on the inner and
outer walls 94 and 96 of the seal 50. It has been found that this
arrangement can provide improved sealing performance of the lip 64
against the stem 20 and of the lip 66 against the sleeve 30, even
under varying loads, pressures, and conditions.
[0046] As an alternative to the cantilever spring 60, other
finger-type springs, flexible fingers, or flexible linear members
might be utilized. Such members can be disposed, bent, or
compressed between the inner and outer walls 94 and 96 to provide
force on these walls to improve the performance of the seal 50.
[0047] Other embodiments are also possible. For example, FIG. 5
depicts another embodiment of a stem seal module 70 made and
operating according to principles of the present inventions. In
this embodiment, the module 70 includes a retainer or cap 72, which
can be made of a suitable material, such as a material that will
reduce friction with the stem 20. For example, a metal or metal
alloy could be utilized, such as an aluminum bronze alloy like
AMPCO 18. The retainer 72 can include a threaded portion 73 for
threadably engaging the body or housing 12 of the nozzle, and thus
for allowing the ease of insertion and removability of the module
70. Other engagements between the retainer 72 and the body 12 could
be utilized as alternatives. The retainer 72 includes a central
passage or opening for receiving the stem 20 and allowing the stem
to move freely upwardly and downwardly within the passage, in order
to selectively permit and restrict the flow of fluid through the
dispenser.
[0048] In addition, the module 70 includes an insert 74 also having
a central passage or opening 71 for receiving the stem 20. The
insert 74 also engages the retainer 72 forming a two piece module
with an internal chamber. In particular, in this example, the
retainer 72 includes a reduced diameter portion 77 having a
diameter D.sub.2, while the insert 74 includes thin upper walls 79
having a spacing slightly larger than the diameter D.sub.2 such
that the walls 79 of the insert 74 surround the reduced diameter
portion 77 of the retainer 72, until the upper surface of the walls
abut the larger portion of the retainer 72. Thus, the retainer 72
is nested within the insert 74. Other structures for engaging the
members 72 and 74 can be provided, such as by interference
fittings, other piloted configurations, and/or threadable
engagements or similar interlocking arrangements, for example.
Because the distance between opposite surfaces of the walls 79 is
larger than the diameter of the remainder of the central passage 71
of the insert 74, a recess 78 is created, which is enclosed by the
retainer 72 once the retainer and insert are engaged with one
another. This recess 78 allows the module 70 to be assembled with
and house a seal when it is engaged with and disengaged with the
housing 12.
[0049] In particular, the module 70 further includes a seal 50 that
can be retained by the removable module, even before it is engaged
with the housing 12. In particular, in this example, the seal 50 is
held within the recess 78. The seal 50 provides a sealing interface
with the stem 20 as it moves in the dispenser. The seal can
comprise a flanged seal with an internal energizing member, such as
has been described above with respect to FIGS. 3-4, or other
suitable sealing member.
[0050] In this example, the removable module 70 also includes a
seal 76 that provides a seal against the housing 12. This seal 76,
in this embodiment, is separate from seal 50 which does not seal
against the housing but rather seals against the stem 20.
Accordingly, the functions of sealing against the stem 20 and
against the housing 12 are provided by separate seal structures in
this embodiment. The seal 50, which can move slightly due to the
stem movement, is isolated from and does not contact the
potentially porous material of the housing 12, but rather contacts
the insert 74 which can be made of a smooth, low-friction, and/or
non-porous material, such as a metal or metal alloy like AMPCO 18
for example. Similarly, seal 76 is does not contact the stem, and
is isolated from the stem movement, such that it experiences little
movement against the porous housing 12. Accordingly, improved
durability and performance are achieved in this embodiment.
[0051] To retain the seal 76 on the module, a second recess 80 is
provided and is defined by and resides between inner extension 81
and outer extension 83. Accordingly, the seal 76 at least partially
resides within the recess 80. However, seal 76 may be sized
slightly larger than the recess, such that, when the module 70 is
threaded into the housing 12, the seal 76 is compressed or crushed
against the lower surface 84 of the inner chamber 17 for the poppet
stem assembly, defined within the housing 12. For example, the seal
76 could comprise a crush seal O-ring made of a suitable material,
such as an elastomer material. In this example, the extension 81 of
the insert 74 engages the poppet stem opening formed in the housing
12 (at the bottom of chamber 17). Accordingly, the poppet stem 20
slidingly engages the insert 74 at this location as well.
[0052] To assemble the module 70 of this example, the seal 76 can
be placed around the extension 81 of the insert 74 and pushed along
the extension until it rests in the recess 80. The seal 50 can be
placed within the recess 78, and the retainer 72 can then be
engaged with the insert 74. Accordingly, at this point, the seals
50 and 76 are held or retained by the module members. This assembly
can occur separate from the fuel dispenser and without the need for
separate tools or for careful placement of the seals within the
dispenser. The module 70 can then be engaged with the housing 12,
such as by threading the retainer 72 into the housing chamber 17.
While threading the retainer 72, the seal 76 compresses against the
housing surface 84, providing a fluid tight crush seal against the
housing. The poppet stem 20 can be slided through the middle of the
module 70, and thus resides at the center of and is surrounded by
the retainer 72, the seal 50, the insert 74, and the seal 76. All
of these components in this embodiment therefore have a passage
through their center having a diameter, at least at some portion,
that is approximately the same as or slightly larger than the
diameter of the stem 20. The seal 50 can include a flange or
extension that abuts the stem 20 to provide a fluid tight seal
against the stem. As the stem is inserted through the module 70,
the seal 50 can compress radially within the recess 78 to provide
the sealing force against the stem. The recess 78 restrains the
seal 50 from movement as the stem 20 slides up and down against the
seal 50 during use. The low friction material of the insert 74
results in reduced wear on the seal 50 as the stem moves. The seal
76 is isolated from the stem 20 and therefore does not move in
response to the stem.
[0053] FIGS. 6 and 7 depict embodiments of fuel dispensing
assemblies made and operating according to principles of the
present inventions, each being fitted with the sliding stem seal
modules of FIGS. 2 and 5 respectively. These embodiments illustrate
components that can be included, as desired or appropriate, when
the inventive principles are applied to a fuel dispensing assembly.
Examples of some such components will now be briefly described. In
this example, the assembly includes a main body 101/201, such as
can be made of cast aluminum, and a stem assembly 102/202, which
can include a stainless steel stem and a wear resistant tip. The
sealing system in these embodiments can include a removable module
28/70 which assists in retaining one or more seals (50 and 48/76),
even when the module 28/70 is disengaged from the fuel dispenser,
as was described in detail above.
[0054] A manual lever or actuator assembly 119/219 can also be
provided, which in this example includes a lever, a lower lever, a
trigger, a spring to bias the trigger, and a rivet for securing the
components. Near the top of the stem is provided a disc holder
108/208 which retains a disc 109/209, both of which are provided on
a skirt 110/210. These components serve as an interface between the
stem and the main spring 111/211 which biases the stem. O-rings
112/212 or similar seals can be provided for sealing of components,
as shown. A filter screen 154/254 can also be provided to filter
the pressurized fuel flowing through the nozzle from the inlet end
180/280 to the outlet end 190/290. A guard sub-assembly 123/223 can
also be provided to guide and protect the lever 119/219, and can
include a guard piece, a rack, and a rivet.
[0055] The operation of the lever assembly 119/219 with respect to
the stem assembly 102/202 can be similar to that described above
with respect to the other embodiments. In particular, movement of
the poppet stem 102/202 by the lever 119/219 can move the skirt
110/210 and disc 109/209 off of their seat, permitting fuel to flow
through the housing, and in particular, from the inlet end 180/280,
around the poppet stem 102/202 and shut off components held within
the housing (described below), and out the spout end 190/290.
[0056] Another spring 143/243 can be provided between a body cap
113/213 and a vapor valve 141/241, which can comprise, for example,
a valve body, a stem 142/242, a lip seal, an insert, retaining
rings, and a disc and disc holder. The spring 143/243 can be used
for biasing the vapor valve. Another retaining ring 135/235 can be
provided for retention of components. The vapor valve can operate
as known in the art for flow of vapors.
[0057] In addition, a shut-off valve assembly 132/232 can be
provided for automatic shut off of the fuel flow upon detection of
a full condition in a fuel tank. This assembly can include a
diaphragm biased by a spring, a support cup, a support, and other
components such as a snubber, a wear washer, and a cap. In
addition, a diaphragm sub-assembly 133/233 can be provided, which
can include a diaphragm and diaphragm support, a lower diaphragm
connector, a flat washer, and an upper pin and spring pin.
Additional shut-off components can include a diaphragm spring
114/214, a latch spring 115/215, a latch ball 122/222, a latch ring
134/234, and a latch plunger 116/216, and the shut-off components
can connect with the lever 119/219 via a plunger pin 120/220 and
push nut 121/221. These components can operate in ways known in the
art, or later to be developed, for automatic shut off of the
nozzle, such as by using Venturi vacuum principles for example.
[0058] The spout end of the fueling nozzle can include a spout
sub-assembly 118/218 including a tube, spring, poppet, bleeder seat
ring/outer tube, sleeve, and ferrule, as well as various O-rings
for sealing, and retaining rings for securing components. A vapor
escape guard 148/248, and clamp 149/249 therefor, can also be
provided to prevent escape of vapors. An anchor spring 155/255 and
ring 156/256 can also be utilized. The spout components can operate
as known in the art or in a desired manner.
[0059] Other components can also be provided, as needed or desired,
to create the appropriate fueling nozzle for the application at
issue. For example, rivets 125/225 and screws 130/230 can be
provided for securing components together, insulating material
126/226 and 140/240 can be provided to insulate the metal pieces
from the user, identification washer 136/236 and screw 137/237 can
be provided for identification of the nozzle, and O-rings 138/238,
139/239, 128/228, 129/229, and 124/224 can be provided for
appropriate sealing of components.
[0060] The modules 28 and 70 of these embodiments therefore operate
to seal fluid from leaking along the stem or along the main body.
These modules 28 and 70 can exhibit increased durability and
performance and reduced assembly requirements.
[0061] The foregoing description of the various embodiments of the
invention has been presented for the purposes of illustration and
description. It is not intended to be exhaustive or to limit the
inventions to the precise form disclosed. Many alternatives,
modifications and variations will be apparent to those skilled in
the art of the above teaching. For example, although the module is
shown as comprising multiple engaged members and two seals in some
embodiments, the module could comprise a single integrated
component and/or a single seal in other embodiments of the
invention. As another example, although multiple inventive aspects
have been presented, such aspects need not be utilized in
combination, and various combinations of aspects are possible in
light of the various embodiments provided above. Accordingly, it is
intended to embrace all possible alternatives, modifications,
combinations, and variations that have been discussed and suggested
herein, and all others that fall within the principles, spirit and
broad scope of the inventions as defined by the claims.
* * * * *