U.S. patent application number 11/582233 was filed with the patent office on 2007-04-26 for intermittent sealing device and method.
Invention is credited to Jon M. Ballou, David Gordon Wilson.
Application Number | 20070089283 11/582233 |
Document ID | / |
Family ID | 37762708 |
Filed Date | 2007-04-26 |
United States Patent
Application |
20070089283 |
Kind Code |
A1 |
Wilson; David Gordon ; et
al. |
April 26, 2007 |
Intermittent sealing device and method
Abstract
An exemplary embodiment disclosed herein relates to an
articulatable sealing device. The device includes a plurality of
seal elements each of which is urgable against a seal-surface, a
fixing member tightenable about a perimeter of the seal elements,
and a retractor in operable communication with the plurality of
seal elements and able to move the plurality of seal elements in a
desired direction.
Inventors: |
Wilson; David Gordon;
(Winchester, MA) ; Ballou; Jon M.; (Beverly,
MA) |
Correspondence
Address: |
CANTOR COLBURN, LLP
55 GRIFFIN ROAD SOUTH
BLOOMFIELD
CT
06002
US
|
Family ID: |
37762708 |
Appl. No.: |
11/582233 |
Filed: |
October 17, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60728991 |
Oct 21, 2005 |
|
|
|
Current U.S.
Class: |
29/428 |
Current CPC
Class: |
F16L 19/063 20130101;
F16J 15/065 20130101; F28D 19/047 20130101; Y10T 29/49826 20150115;
Y10T 29/49863 20150115; Y10T 29/4987 20150115; F16J 15/067
20130101; Y10T 29/49874 20150115; F16J 15/346 20130101; Y10T 29/49
20150115; F16J 15/061 20130101 |
Class at
Publication: |
029/428 |
International
Class: |
B21D 39/03 20060101
B21D039/03 |
Claims
1. An articulatable sealing device, comprising: a plurality of seal
elements each of which is urgable against a seal-surface; a fixing
member tightenable about a perimeter of the seal elements; and a
retractor in operable communication with the plurality of seal
elements and able to move the plurality of seal elements in a
desired direction.
2. The sealing device of claim 1, further comprising: at least one
biasing member to urge the plurality of seal elements.
3. The sealing device of claim 1, wherein the retractor is engaged
with the fixing member.
4. The sealing device of claim 1, wherein the retractor is engaged
with at least one of the plurality of seal elements.
5. The sealing device of claim 1, wherein each seal element of the
plurality of seal elements has an arcuate male edge and an arcuate
female edge and the arcuate male edge is on a side of the seal
element opposite the side with the arcuate female edge and the
arcuate male edge of one seal element is engagable with the arcuate
female edge of an adjacent seal element and is sealable
thereto.
6. The sealing device of claim 1, wherein tightening of the fixing
member around the perimeter of the plurality of seal elements fixes
the seal elements to one another.
7. The sealing device of claim 1, further comprising: a clamp
actuator for tightening the fixing member about the perimeter of
the plurality of seal elements.
8. The sealing device of claim 1, wherein the plurality of seal
elements are slidable relative to one another in response to the
fixing member not being tightened.
9. The sealing device of claim 1, further comprising: a seal guide
for orienting the plurality of seal elements into a seal shape.
10. The sealing device of claim 1, wherein the plurality of seal
elements are shaped to form a desired seal line shape.
11. The sealing device of claim 1, wherein the plurality of seal
elements seal to one another forming a closed shape sealable to a
duct.
12. The sealing device of claim 1, wherein the plurality of seal
elements are made of ceramic.
13. The sealing device of claim 1, wherein the number of seal
elements in the seal device is selected to minimize leakage between
the seal device and a seal-surface.
14. The sealing device of claim 1, further comprising: a plurality
of push-rods sized to communicate the urging force of the at least
one biasing member to the plurality of seal elements while
preventing excess heat from reaching the at least one biasing
member.
15. The sealing device of claim 1, further comprising: at least one
pull rod sized to communicate an urging force of the retractor to
the fixing member while preventing excess heat from reaching the
retractor.
16. An articulatable sealing device, comprising: a plurality of
seal elements; a fixing member for intermittently fixing the seal
elements to one another; a retractor for intermittently retracting
the seal elements from contact with a seal-surface; and at least
one biasing member to urge each of the plurality of seal elements
individually against a seal-surface.
17. A method of intermittently sealing to a surface, comprising:
independently urging at least one of a plurality of seal elements
toward a seal-surface; intermittently clamping the plurality of
seal elements to one another; intermittently lifting the clamped
plurality of seal elements away from the seal-surface; and
intermittently releasing the clamp to thereby allow the seal
elements to independently move toward and seal against a
seal-surface.
18. The method of claim 17, further comprising: sealing the
plurality of seal elements to one another to form a perimeter
defining a closed shape.
19. The method of claim 17, further comprising: moving the lifted
and clamped seal elements relative to a seal-surface prior to
releasing the clamp.
20. The method of claim 17, further comprising: individually
shaping the plurality of seal elements to form a desired closed
shape.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority to U.S. provisional
application, 60/728,991, filed Oct. 21, 2005, the entire contents
of which are incorporated herein by reference.
BACKGROUND OF THE INVENTION
[0002] Seal arrangements between two members, which are in movement
relative to each other, are known in the arts. But at high
temperatures, above 500.degree. C. for example, and applications
where the leakage across the seal has to be minimal, of the order
of 0.1% to 3.0%, over an extended lifecycle many of the
conventional sealing mechanisms cannot comply with these
requirements. One example of such an application is a regenerative
heat exchanger (regenerator) in which a porous disk or drum is
first rotated into a hot fluid flow and second into a cold fluid
flow to thereby transfer heat from the hot fluid to the cold fluid.
To minimize the wear of the seals in contact with the moving
regenerator disk a discontinuous moving regenerator disk, with
lifting seals, has been used. A description of such a regenerator
can be found in U.S. Pat. No. RE37134 to David Gordon Wilson, which
is included as a reference in its entirety herein. In some
regenerator applications the mixing of the cold and the hot fluid
is troublesome and should, therefore, be minimized. Such a mixing
of hot and cold fluids results from leakage by the seals between
the two fluids. In applications using lifting seals in
discontinuous regenerators, the leakage, though low, may still be
greater than desired due to distortions in the seal-surface. Such
distortions may hold the lifting seals far enough from the
seal-surface to permit unacceptable levels of leakage to occur.
Accordingly, improvements in sealing in the presence of such
seal-surface distortions would be desirable in the art.
BRIEF DESCRIPTION OF THE INVENTION
[0003] An exemplary embodiment disclosed herein relates to an
articulatable sealing device. The device includes a plurality of
seal elements each of which is urgable against a seal-surface, a
fixing member tightenable about a perimeter of the seal elements,
and a retractor in operable communication with the plurality of
seal elements and able to move the plurality of seal elements in a
desired direction.
[0004] Further disclosed herein relates to an articulatable sealing
device. The device includes, a plurality of seal elements, and a
fixing member for intermittently fixing the seal elements to one
another. The device further includes a retractor for intermittently
retracting the seal elements from contact with a seal-surface, and
at least one biasing member to urge each of the plurality of seal
elements individually against a seal-surface.
[0005] Further disclosed herein is an exemplary embodiment of a
method of intermittently sealing to a surface. The method includes,
independently urging at least one of a plurality of seal elements
toward a seal-surface, intermittently clamping the plurality of
seal elements to one another, and intermittently lifting the
clamped plurality of seal elements away from the seal-surface. The
method further includes intermittently releasing the clamp to
thereby allow the seal elements to independently move toward and
seal against a seal-surface.
BRIEF DESCRIPTION OF THE DRAWINGS
[0006] The following descriptions should not be considered limiting
in any way. With reference to the accompanying drawings, like
elements are numbered alike:
[0007] FIG. 1 depicts a perspective view of a regenerator disclosed
herein;
[0008] FIG. 2 depicts a plan view of a matrix disclosed herein;
[0009] FIG. 3 depicts a plan view of a matrix, a plurality of seal
elements and a fixing member disclosed herein;
[0010] FIGS. 4A-4D depict perspective views of various stages of
actuation of a sealing device disclosed herein;
[0011] FIG. 5 depicts a cross sectional view of the regenerator
shown in FIG. 1; and
[0012] FIG. 6 depicts an exploded perspective view of the sealing
device shown in FIG. 1.
DETAILED DESCRIPTION OF THE INVENTION
[0013] A detailed description of embodiments of the disclosed
apparatus and method are presented herein by way of exemplification
and not limitation with reference to the Figures.
[0014] Referring to FIG. 1 an embodiment of the invention will now
be had with reference to a discontinuous regenerator shown
generally at 10. The regenerator 10 includes a rotatable porous
matrix 14, a fluid-carrying duct 18 and an actuatable seal device
22. The heat exchanger 10 is shown with a single duct 18 and seal
device 22 employed; however, it should be understood that more than
one duct 18 and seal device 22 may be employed on either or both
sides of the matrix 14 while still remaining within the spirit and
scope of the present invention.
[0015] The porous matrix 14 of the regenerator 10 has a
seal-surface 24 thereon and a plurality of discrete flow
compartments 26; four such compartments are illustrated in FIG. 1.
Surrounding each flow compartment 26 is a seal line 30. Each seal
line 30 defines a perimeter around one of the flow compartments 26
on the seal-surface 24. The seal device 22 forms a seal against the
seal-surface 24 at the seal line 30 when the seal device 22 is
actuated to the seal position. The seal line 30 may be in the shape
of a circle as shown in FIG. 1 or may be other shapes such as
triangular, for example, as is shown by a seal line 32 shown in
FIG. 2. There are limitations on the shapes that the seal lines 30,
32 may take and these limitations are based on the construction of
the seal device 22 that will be discussed in more detail now.
[0016] Referring again to FIG. 2, the seal device 22 uses a
plurality of seal elements 34 to form the seal against the seal
line 30 on the seal-surface 24 as is shown in this partial cross
sectional view of the seal elements 34. In this embodiment each
seal element 34 has a female radiused edge 38 and a male radiused
edge 42 on a side opposite of the female radiused edge 38. The male
edge 42 of one seal element 34 engages with the female edge 38 of
an adjacent seal element 34 to form a seal between adjacent seal
elements 34 while allowing the adjacent seal elements 34 to move
and slide axially relative to one another. The shape of each seal
element 34, in a seal device 22, can be identical to all the other
seal elements 34 in the seal device 22 if for example the seal line
30 is a circle. Alternatively, the seal elements 34 may have
various shapes in order to form a non-circular shape, as is the
case for the seal line 32, for example. The number of seal elements
34 that are used by each seal device 22 can vary depending upon the
particular application. The more seal elements 34 that are used for
a given seal line 30, 32 the more the seal device 22 is able to
seal against surfaces with imperfections as will be described below
with reference to FIGS. 4A-4D.
[0017] Referring to FIG. 3 a seal element fixing member illustrated
herein as a clamp ring 46 surrounds the perimeter of the seal
elements 34. A clamp actuator 50 when actuated pulls the clamp ring
46 into tension around the seal elements 34, thus putting all of
the seal elements 34 that create the closed shape into a
circumferentially compressive force with each other seal element 34
in the particular seal device 22. The compressive force between
adjacent seal elements 34 creates friction between adjacent seal
elements 34 that causes the seal elements 34 to lift together as
one assembly when they are lifted away from the matrix 14. The
compressive force between adjacent seal elements 34 also creates a
seal between adjacent elements 34 thereby preventing leakage
therebetween. The clamp actuator 50 that tightens the clamp ring 46
may be pneumatic, hydraulic, servomotor controlled or controlled by
any other applicable actuation that is known.
[0018] Referring to FIGS. 4A-4D various phases of the seal device
22 showing the clamping and releasing of the clamp ring 46 about
the seal elements 34 and pulling and pushing of the seal elements
34 relative to the seal-surface 24 are shown in detail. In FIG. 4A
the clamp ring 46 is in tension around the seal elements 34 and the
seal elements 34 are sealed against the seal line 30 of the matrix
14. The clamp ring 46 has the seal elements 34 locked together as
an assembly and can therefore be lifted away from the matrix 14 in
the direction of arrows 54. With the seal elements 34 lifted away
from the matrix 14 to form a clearance gap 56 as shown in FIG. 4B
the matrix 14 is able to move, in direction of arrow 57 for
example, relative to the seal elements 34 without causing wear of
the seal elements 34. Each of the seal elements 34 is individually
biased, in the direction of arrows 60, toward the matrix 14 such
that upon release of the tension in the clamp ring 46 the biasing
force urges the individual seal elements 34 to move toward and make
contact with the matrix 14 as is shown in FIG. 4C. By individually
urging each of the seal elements 34 the seal device 22 can permit
each seal element 34 to make contact with the matrix 14. In so
doing the largest gaps that will exist between the seal elements 34
and the matrix 14 will be smaller than if the seal elements 34 were
not able to move independently of one another. This gap-size
reduction of embodiments disclosed herein is especially effective
in reducing gap sizes that occur when a distortion 58 exists on the
surface of the matrix 14. The use of multiple seal elements 34
allows a single seal element 62 to be axially displaced with
respect to the other seal elements 34 due to a local distortion 58,
for example, and thereby to decrease the overall leakage that would
result had the seal elements 34 not been allowed to move
independently from the seal element 62 towards matrix 14.
Embodiments with a greater number of seal elements 34 for a
specific size seal line 32 will have smaller gap sizes since fewer
seal elements 34 will be held away from the seal-surface 24 by the
distortion 58. Once all the seal elements 34, 62 have moved toward
and made contact with the matrix 14 the actuator 50 can actuate and
apply tension to the clamp ring 46 to thereby lock the seal
elements 34 together sealing them to one another and preventing
movement of any individual seal element 34 in a direction away from
the matrix 14.
[0019] Referring to FIGS. 1, 5 and 6 a detailed description of the
seal device 22 and the mechanisms to control the movements of the
seal elements 34 will now be described. In addition to the clamp
ring 46 a ring shaped seal guide 70, which is attached to a guide
flange 74, also surrounds and provides guidance to the seal
elements 34. The seal guide 70 loosely surrounds the seal elements
34 to allow the seal elements 34 to move freely in an axial
direction relative to the seal guide 70. The seal elements 34 ride
on an outer surface 78 of the duct 18 and are sealed to the surface
78 with packing 82. The packing 82 is contained within a channel 86
formed circumferentially in the seal elements 34. Insulation 90
lines the inside of the duct 18 to minimize heat transfer to the
seal device 22. For sealing between the duct 18 and the seal
elements 34 known methods such as 0-rings, for example, can be used
if appropriate to the particular application. The seal guide 70 is
stationary relative to the duct 18 and thus the seal elements 34
move relative to the seal guide 74.
[0020] The seal guide 74 can have a noncircular shape to control
the shape of the seal elements 34 such that they form a noncircular
seal shape such as would be required to seal against seal line 32
as shown in FIG. 2. The duct 18 may also have a noncircular shape
to complement the shape of the seal guide 74. There are limits to
the shapes that the seal line 32 and consequently the seal device
22 can take, however, which are due to the possibility of the seal
elements 34, 62 collapsing radially inwardly if the compressive
force applied to the seal elements 34, 62 is allowed to buckle an
interface between seal elements 34, 62 radially inwardly. It is
therefore recommended to maintain a convex curvature around the
full perimeter of the seal line 32 to prevent such a buckling from
occurring.
[0021] As described above the seal elements 34 move in both axial
directions, specifically toward and away from the matrix 14. Holes
94 and 98 through the guide flange 74 permit pull rods 104 and
push-rods 108 respectively to extend therethrough to urge the
motion of the seal elements in the two directions. The push-rods
108 are also slidably engaged in holes 118 in an actuation support
plate 122 that is attached to the duct 18 further from the location
where the seal guide 74 is fixed to the duct 18. Each push-rod 108
has a push-rod biasing member depicted herein as a compression
spring 126 compressed between the support plate 122 and a flange
130 on the push-rods 108. Thus the compression spring 126 is always
in compression and is thereby supplying an urging force to the seal
element 34 to which it is engaged in a direction toward the matrix
14. The push-rods 108 engage recesses 134 in the seal elements 34
to positively locate the push-rods 108 relative to the seal
elements 34.
[0022] Each pull rod 104 is connected to a seal element retractor
illustrated herein as an axial actuator 138 that when actuated
pulls the pull rod 104 in a direction away from the matrix 14. The
axial actuator 138 may be pneumatic, hydraulic, servomotor
controlled or controlled by any other applicable actuation that is
known. A head 142 on each rod 104, on the opposite end of the rod
104 than is connected to the actuator 138, engages with a latch 146
fixed on the clamp ring 46. Thus, when the actuator 138 is actuated
the pull rod 104 pulls the clamp ring 46 in a direction away from
the matrix 14. Several pull rods 104 and actuators 138 can be
positioned around the seal guide 74 and support plate 122 to evenly
distribute the load of the rods 104 on the clamp ring 46 to thereby
control the motion of the clamp ring 46 resulting from the forces
applied thereto. Alternate embodiments could have the pull rods 104
engaged directly to one or more of the seal elements 34. Since the
seal elements 34 are secured to one another by the clamp ring 46
retracting the pull rods 104 with the actuator 138 would retract
all of the seal elements 34 as well.
[0023] Depending upon the particular application employing the
regenerator 10 disclosed herein, the temperatures of the fluid
being sealed could be very high. For example in a gas turbine
engine the hot fluid temperatures may be high enough to damage the
springs 126 and the actuators 138 if they are located near the
seal-surface 24 during times when the seal elements 34 are at the
gap 56 distance from the seal-surface 24. To protect the springs
126 and the actuators 138, therefore, it may be desirable to locate
the springs 126 and the actuators 138 at specific distances from
these high-temperature locations. The lengths of the pull rods 104
and the push-rods 108 may therefore be customized for each
application, such that longer rods 104, 108 are used for
applications with higher-temperature fluids, for example, to
thereby protect the springs 126 and the actuators 138 from heat
damage. In applications with high temperatures it may be
advantageous to use seal elements 34 made from materials such as
ceramic, for example, such that the seal elements 34 may withstand
the high temperatures without sustaining damage.
[0024] With the construction just described the push-rods 108 in
response to the clamp actuator 50 releasing the tension in the
clamp ring 46 are able to push the seal elements 34, individually,
into contact with the seal-surface 24 of the matrix 14.
Additionally, the pull rods 104 are able to pull all of the seal
elements 34 simultaneously away from the seal-surface 24 of the
matrix 14 in response to the clamp actuator 50 applying tension to
the clamp ring 46. After this action the seal elements 34 are no
longer in contact with the matrix 14 allowing the matrix 14 to move
without causing wear of the seal elements 34.
[0025] While the invention has been described with reference to an
exemplary embodiment or embodiments, it will be understood by those
skilled in the art that various changes may be made and equivalents
may be substituted for elements thereof without departing from the
scope of the invention. In addition, many modifications may be made
to adapt a particular situation or material to the teachings of the
invention without departing from the essential scope thereof.
Therefore, it is intended that the invention not be limited to the
particular embodiment disclosed as the best mode contemplated for
carrying out this invention, but that the invention will include
all embodiments falling within the scope of the claims.
* * * * *