U.S. patent application number 10/754283 was filed with the patent office on 2005-07-14 for resonator with retention ribs.
Invention is credited to Connor, Michael J., Knight, Jessie A..
Application Number | 20050150718 10/754283 |
Document ID | / |
Family ID | 34739352 |
Filed Date | 2005-07-14 |
United States Patent
Application |
20050150718 |
Kind Code |
A1 |
Knight, Jessie A. ; et
al. |
July 14, 2005 |
Resonator with retention ribs
Abstract
A resonator includes an inner perforated tube, an outer shell,
and a plurality of annular ribs extending radially therebetween and
defining resonant chambers. Progressive stepping of ribs and
grooves enables axial insertion assembly with minimal cost. The
need for welding or secondary bonding operations is eliminated.
Inventors: |
Knight, Jessie A.;
(Stoughton, WI) ; Connor, Michael J.; (Stoughton,
WI) |
Correspondence
Address: |
ANDRUS, SCEALES, STARKE & SAWALL, LLP
100 EAST WISCONSIN AVENUE, SUITE 1100
MILWAUKEE
WI
53202
US
|
Family ID: |
34739352 |
Appl. No.: |
10/754283 |
Filed: |
January 9, 2004 |
Current U.S.
Class: |
181/250 ;
181/273; 181/276 |
Current CPC
Class: |
F02M 35/1266 20130101;
F01N 1/02 20130101; F02M 35/1216 20130101 |
Class at
Publication: |
181/250 ;
181/273; 181/276 |
International
Class: |
F01N 001/02; F01N
001/08 |
Claims
What is claimed is:
1. A resonator extending axially along an axis between distally
opposite axial ends providing an inlet and an outlet, said
resonator comprising an inner perforated tube, an outer shell, and
at least one annular rib spaced axially between said inlet and said
outlet and extending radially between said inner perforated tube
and said outer shell and defining a first resonant chamber between
said inner perforated tube and said outer shell axially upstream of
said rib, and defining a second resonant chamber between said inner
perforated tube and said outer shell axially downstream of said
rib, said inner perforated tube having a first set of perforations
radially aligned with said first resonant chamber, said inner
perforated tube having a second set of perforations radially
aligned with said second resonant chamber.
2. The resonator according to claim 1 wherein said resonator
attenuates sound waves in gas flow entering said resonator at said
inlet and exiting said resonator at said outlet, the gas flowing
axially through said inner perforated tube and communicating with
said first and second resonant chambers through said first and
second sets of perforations, respectively.
3. The resonator according to claim 2 wherein said rib isolates
said first resonant chamber from said second resonant chamber.
4. The resonator according to claim 2 wherein said rib seals said
first resonant chamber from said second resonant chamber.
5. The resonator according to claim 2 wherein: said first set of
perforations are the only inlet to and the only exit from said
first resonant chamber, such that gas flow in said inner perforated
tube can enter said first resonant chamber only through said first
set of perforations, and can exit said first resonant chamber only
through said first set of perforations; said second set of
perforations are the only inlet to and the only exit from said
second resonant chamber, such that gas flow in said inner
perforated tube can enter said second resonant chamber only through
said second set of perforations, and can exit said second resonant
chamber only through said second set of perforations.
6. The resonator according to claim 5 wherein said gas flow enters
said resonator at said inlet only through said inner perforated
tube, and said gas flow exits said resonator at said outlet only
through said inner perforated tube.
7. The resonator according to claim 2 wherein said rib extends
radially outwardly from said inner perforated tube and has an outer
tip, and said outer shell has an inner surface facing radially
inwardly toward said inner perforated tube and has an engagement
surface engaging said outer tip of said rib in radially engaged
relation such that said inner perforated tube is axially insertable
into said outer shell and held in radially engaged relation
therein.
8. The resonator according to claim 7 wherein said outer tip of
said rib engages said engagement surface in sealing relation
isolating said first resonant chamber from said second resonant
chamber.
9. The resonator according to claim 7 wherein said engagement
surface comprises a detent engaging said outer tip of said rib in
snap-fit relation.
10. The resonator according to claim 7 wherein said outer shell has
an outer surface with an annular groove recessed radially inwardly
toward said inner perforated tube and providing said engagement
surface.
11. The resonator according to claim 2 wherein said inner
perforated tube and said outer shell have upstream axial ends
mating at an upstream joint blocking gas flow therepast at said
inlet such that gas flow at said inlet can only flow into said
perforated inner tube and not into the space between said inner
perforated tube and said outer shell, and wherein said inner
perforated tube and said outer shell have downstream axial ends
mating at a downstream joint blocking gas flow therepast at said
outlet such that gas flow at said outlet can only flow from said
perforated inner tube and not from the space between said inner
perforated tube and said outer shell.
12. The resonator according to claim 11 wherein: one of said
upstream axial ends of said inner perforated tube and said outer
shell has first and second different diameter portions and a first
transition portion therebetween, said first diameter portion being
larger than said second diameter portion and mating with the other
of said upstream axial ends of said inner perforated tube and said
outer shell, said first transition portion extending radially
inwardly from said first diameter portion to said second diameter
portion; one of said downstream axial ends of said inner perforated
tube and said outer shell has third and fourth different diameter
portions and a second transition portion therebetween, said third
diameter portion being larger than said fourth diameter portion and
mating with the other of said downstream axial ends of said inner
perforated tube and said outer shell, said second transition
portion extending radially inwardly from said third diameter
portion to said fourth diameter portion.
13. The resonator according to claim 11 wherein: said upstream
axial end of said inner perforated tube has first and second
different diameter portions and a first transition portion
therebetween, said first diameter portion being larger than said
second diameter portion and mating with said outer shell, said
first transition portion extending radially inwardly from said
first diameter portion to said second diameter portion; said
downstream axial end of said outer shell has third and fourth
different diameter portions and a second transition portion
therebetween, said fourth diameter portion being smaller than said
third diameter portion and mating with said inner perforated tube,
said second transition portion extending radially inwardly from
said third diameter portion to said fourth diameter portion.
14. The resonator according to claim 1 wherein said inner
perforated tube is a two-piece member having first and second
pieces abutting each other at first and second axially extending
abutment lines in an assembled condition in said outer shell, and
wherein said first and second pieces are held in said assembled
condition in said outer shell solely by said outer shell, without
bonding or welding of said first and second pieces to each
other.
15. The resonator according to claim 1 wherein said inner
perforated tube is a two-piece member having first and second
pieces abutting each other at first and second axially extending
abutment lines in an assembled condition in said outer shell, said
first and second pieces being identical and enabling the use of a
single tool for forming same, to reduce tooling cost.
16. A resonator extending axially along an axis between distally
opposite axial ends providing an inlet and an outlet, said
resonator comprising an inner perforated tube, an outer shell, and
a plurality of annular ribs axially spaced from each other and
serially axially spaced between said inlet and said outlet and
extending radially between said inner perforated tube and said
outer shell and defining a plurality of resonant chambers between
said inner perforated tube and said outer shell, said inner
perforated tube having a plurality of sets of perforations radially
aligned with respective said resonant chambers.
17. The resonator according to claim 16 wherein the number of said
ribs equals N, where N.gtoreq.2, the number of said resonant
chambers equals N+1, and the number of said sets of perforations
equals N+1.
18. The resonator according to claim 16 wherein said ribs have a
radial height between said inner perforated tube and said outer
shell, and wherein said radial height progressively increases from
rib to rib.
19. The resonator according to claim 18 wherein said ribs extend
radially outwardly from said inner perforated tube, said outer
shell has a plurality of annular grooves axially spaced from each
other and serially axially spaced between said inlet and said
outlet and radially aligned with and engaging respective said ribs,
and wherein said grooves have a radial depth progressively
increasing from groove to groove in inverse relation to the
progression of said progressively increasing height of said
ribs.
20. The resonator according to claim 19 wherein the shortest radial
height rib engages the deepest radial depth groove, and the tallest
radial height rib engages the shallowest radial depth groove.
21. The resonator according to claim 20 wherein said inner
perforated tube is insertable axially into said outer shell, and
wherein said progressively increasing radial depth of said grooves
in inverse relation to the progression of the progressively
increasing height of said ribs facilitates said axial
insertion.
22. The resonator according to claim 19 wherein the number of said
ribs equals N, where N.gtoreq.2, the number of said grooves equals
N, the number of said resonant chambers equals N+1, and the number
of said sets of perforations equals N+1.
23. A method for assembling a resonator extending axially along an
axis between distally opposite axial ends, namely an inlet and an
outlet, comprising providing an inner perforated tube, providing an
outer shell, providing at least one annular rib on one of said
inner perforated tube and said outer shell, and axially inserting
said inner perforated tube into said outer shell.
24. The method according to claim 23 comprising axially inserting
said inner perforated tube into said outer shell such that said rib
is spaced axially between said inlet and said outlet and extends
radially between said inner perforated tube and said outer shell
and defines a first resonant chamber between said inner perforated
tube and said outer shell axially upstream of said rib, and defines
a second resonant chamber between said inner perforated tube and
said outer shell axially downstream of said rib, providing said
inner perforated tube with a first set of perforations radially
aligned with said first resonant chamber, providing said inner
perforated tube with a second set of perforations radially aligned
with said second resonant chamber.
25. The method according to claim 24 comprising providing said rib
extending radially outwardly from said inner perforated tube and
having an outer tip, providing said outer shell with an inner
surface facing radially inwardly toward said inner perforated tube
and having an engagement surface, axially inserting said inner
perforated tube into said outer shell such that said outer tip of
said rib engages said engagement surface in radially engaged
relation such that said inner perforated tube and said outer shell
are held in radially engaged relation.
26. The method according to claim 25 comprising engaging said outer
tip of said rib and said engagement surface in sealing relation
isolating said first resonant chamber from said second resonant
chamber.
27. The method according to claim 25 comprising providing said
engagement surface as a detent, and inserting said inner perforated
tube into said outer shell such that said outer tip of said rib
engages said detent in snap-fit relation.
28. The method according to claim 25 comprising providing said
outer shell with an outer surface having an annular groove recessed
radially inwardly toward said inner perforated tube and having an
inner surface providing said engagement surface, and comprising
inserting said inner perforated tube axially into said outer shell
such that said outer tip of said rib engages said engagement
surface.
29. The method according to claim 23 comprising providing said
inner perforated tube as a two-piece member having first and second
pieces, abutting said first and second pieces at first and second
axially extending abutment lines to a pre-assembled condition,
inserting said first and second pieces in said pre-assembled
condition axially into said outer shell such that said first and
second pieces are held in assembled condition in said outer shell
solely by said outer shell, without bonding or welding of said
first and second pieces to each other.
30. The method according to claim 23 comprising providing said
inner perforated tube as a two-piece member having identical first
and second pieces, abutting said first and second pieces to each
other at first and second axially extending abutment lines in a
pre-assembled condition, axially inserting said first and second
pieces in said pre-assembled condition into said outer shell.
31. The method according to claim 30 comprising forming said first
and second identical pieces by the same tool, to reduce tooling
cost.
32. A method for assembling a resonator extending axially along an
axis between distally opposite axial ends, namely an inlet and an
outlet, comprising providing an inner perforated tube, providing an
outer shell, providing a plurality of annular ribs axially spaced
from each other and serially axially spaced between said inlet and
said outlet for extending radially between said inner perforated
tube and said outer shell and defining a plurality of resonant
chambers between said inner perforated tube and said outer shell,
providing said inner perforated tube with a plurality of sets of
perforations to be radially aligned with respective said resonant
chambers, and axially inserting said inner perforated tube into
said outer shell.
33. The method according to claim 32 comprising providing N said
ribs, where N.gtoreq.2, providing N+1 said resonant chambers, and
providing N+1 said sets of perforations.
34. The method according to claim 32 comprising providing said ribs
with a radial height extending between said inner perforated tube
and said outer shell, and progressively increasing said radial
height from rib to rib.
35. The method according to claim 32 comprising providing said ribs
extending radially outwardly from said inner perforated tube,
providing said outer shell with a plurality of annular grooves
axially spaced from each other and serially axially spaced between
said inlet and said outlet and radially aligned with and engaging
respective said ribs, providing said grooves with a radial depth
progressively increasing from groove to groove in inverse relation
to the progression of said progressively increasing height of said
ribs.
36. The method according to claim 35 comprising, upon axial
insertion of said inner perforated tube into said outer shell:
engaging the shortest radial height rib with the deepest radial
depth groove; and engaging the tallest radial height rib with the
shallowest radial depth groove.
37. The method according to claim 36 comprising providing said
inner perforated tube without a draft, and inserting said inner
perforated tube axially into said outer shell without a draft.
38. The method according to claim 35 comprising providing N said
ribs, where N.gtoreq.2, providing N said grooves, providing N+1
said resonant chambers, and providing N+1 said sets of
perforations.
Description
BACKGROUND AND SUMMARY
[0001] The invention relates to resonators, including intake
resonator silencers for internal combustion engines.
[0002] Intake resonators are known in the art, and are constructed
from various materials including metal and/or plastic. Blow molded
bottle style resonators are known and fitted under the hood of
automobiles, trucks, agricultural and construction vehicles, marine
vehicles, and recreational vehicles. Various constructions employ
hollow structures made of plastic which are bonded together using
vibration or sonic welding or other types of friction welding.
Other types of structures have additional elastomer seals, adding
expense. Other structures of reduced cost are not gas tight, and
therefore lack in performance.
[0003] The present invention provides a simple, cost effective
resonator without performance trade-off.
BRIEF DESCRIPTION OF THE DRAWING
[0004] FIG. 1 is a perspective assembly view of a resonator in
accordance with the invention.
[0005] FIG. 2 is a cut-away view of the assembly of FIG. 1.
[0006] FIG. 3 is a sectional view taken along line 3-3 of FIG.
1.
[0007] FIG. 4 is a perspective view partially cut-away of the inner
perforated tube of FIGS. 1-3.
DETAILED DESCRIPTION
[0008] FIG. 1 shows a resonator 10 extending axially along an axis
12 between distally opposite axial ends 14 and 16 providing an
inlet and an outlet, respectively, for example for receiving intake
combustion air at inlet 14 and delivering the combustion air from
outlet 16 to an internal combustion engine (not shown). Resonator
10 has an inner perforated tube 18, FIGS. 2-4, an outer shell 20,
and at least one and preferably two or more annular ribs such as
22, 24 spaced axially between inlet 14 and outlet 16 and extending
radially between inner perforated tube 18 and outer shell 20. In
preferred form, inner tube 18 is an injection molded plastic
member, and outer shell 20 is a blow molded or rotationally molded
plastic member, and the ribs extend integrally radially outwardly
from inner tube 18. The ribs define a first resonant chamber 26
between inner perforated tube 18 and outer shell 20 axially
upstream of rib 22, a second resonant chamber 28 between inner
perforated tube 18 and outer shell 20 axially downstream of rib 22
and axially upstream of rib 24, and a third resonant chamber 30
between inner perforated tube 18 and outer shell 20 axially
downstream of rib 24. Inner perforated tube 18 has a first set of
perforations 32 radially aligned with resonant chamber 26, a second
set of perforations 34 radially aligned with resonant chamber 28,
and a third set of perforations 36 radially aligned with resonant
chamber 30. The resonator attenuates sound waves in gas flow
entering the resonator at inlet 14 and exiting the resonator at
outlet 16. The gas flows axially through the hollow interior of
perforated tube 18 and communicates with resonant chambers 26, 28,
30 through respective sets of perforations 32, 34, 36.
[0009] The set of perforations 32 are the only inlet to and the
only exit from resonant chamber 26, such that gas flow in the
hollow interior of inner perforated tube 18 can enter resonant
chamber 26 only through the set of perforations 32, and can exit
resonant chamber 26 only through the set of perforations 32. The
second set of perforations 34 are the only inlet to and the only
exit from resonant chamber 28, such that gas flow in inner
perforated tube 18 can enter resonant chamber 28 only through the
set of perforations 34, and can exit resonant chamber 28 only
through the set of perforations 34. The third set of perforations
36 are the only inlet to and the only exit from resonant chamber
30, such that gas flow in inner perforated tube 18 can enter
resonant chamber 30 only through the set of perforations 36, and
can exit resonant chamber only through the set of perforations 36.
The upstream inlet ends 38 and 40 of inner tube 18 and outer shell
20, respectively, engage each other in tight fit flush relation,
such that gas flow enters resonator 10 only through the hollow
interior of inner tube 18. The downstream outlet ends 42 and 44 of
inner tube 18 and outer shell 20, respectively, engage each other
in tight fit flush relation, such that gas flow exits the resonator
at outlet 16 only through the hollow interior of inner perforated
tube 18.
[0010] Rib 22 extends radially outwardly from inner perforated tube
18 and has an outer tip 46. Outer shell 20 has an inner surface 48
facing radially inwardly toward inner perforated tube 18 and has a
sealing engagement surface 50, FIG. 3, engaging outer tip 46 of rib
22 in radially engaged tight fit relation such that inner
perforated tube 18 is axially insertable (downwardly in FIGS. 1-3)
into outer shell 20 and held in radially engaged relation therein,
to be further described. Rib 24 extends radially outwardly from
inner perforated tube 18 and has an outer tip 52. Outer shell 20
has an inner surface 54 facing radially inwardly toward inner
perforated tube 18 and has a sealing engagement surface 56 engaging
outer tip 52 of rib 24 in radially engaged tight fit relation such
that inner perforated tube 18 is axially insertable (downwardly in
FIGS. 1-3) into outer shell 20 and held in radially engaged
relation therein, to be further described. Outer tip 46 of rib 22
engages surface 50 in sealing relation, isolating resonant chamber
26 from resonant chamber 28. Outer tip 52 of rib 24 engages surface
56 in sealing relation, isolating resonant chamber 28 from resonant
chamber 30.
[0011] Resonant chamber 26 is sealed at its upstream end by the
flush tight fit engagement of ends 38 and 40 of inner tube 18 and
outer shell 20, respectively, and is sealed at its downstream end
by the engagement of rib tip 46 and surface 50. Resonant chamber 28
is sealed at its upstream end by the engagement of rib tip 46 and
surface 50, and is sealed at its downstream end by the engagement
of rib tip 52 and surface 56. Resonant chamber 30 is sealed at its
upstream end by the engagement of rib tip 52 and surface 56, and is
sealed at its downstream end by the flush fit tight engagement of
downstream ends 42 and 44 of inner tube 18 and outer shell 20,
respectively.
[0012] Each of sealing engagement surfaces 50 and 56 is a detent
engaging the respective outer tip 46 and 50 of the respective rib
22 and 24 in snap-fit relation upon the noted axial insertion.
Outer shell 20 has an outer surface 58 with an annular groove 60
recessed radially inwardly toward inner perforated tube 18 and
providing the noted sealing engagement surface 50 on inner surface
48. Outer shell 20 has an outer surface 62 with an annular groove
64 recessed radially inwardly toward inner perforated tube 18 and
providing sealing engagement surface 56 on inner surface 54.
[0013] Inner perforated tube 18 is a two-piece member having first
and second pieces 66 and 68 abutting each other at first and second
axially extending abutment lines 70 and 72 in assembled condition
in outer shell 20. Pieces 66 and 68 are preferably held in
assembled condition in outer shell 20 solely by outer shell 20,
without bonding or welding of pieces 66 and 68 to each other.
Further preferably, pieces 66 and 68 are identical, which enables
the use of a single tool for forming same, to reduce tooling cost.
One axially extending edge of each piece, such as edge 74, FIG. 4,
along abutment line 70, is concave as shown at 76, while the other
axially extending edge 78 at abutment line 72 is convex or bulged
as shown at 80 to mate in the concave edge of the other piece.
Other types of interlocking engagement of pieces 66 and 68 may be
used to provide proper alignment of the pieces during axial
insertion into outer shell 20, whereafter the pieces are held in
assembled condition by engagement of ribs 22 and 24 with respective
detents 50 and 56.
[0014] Inner perforated tube 18 and outer shell 20 have the noted
upstream axial ends 38 and 40 mating at an upstream joint 82, FIG.
3, blocking gas flow therepast at inlet 14 such that gas flow at
inlet 14 can only flow into the hollow interior of perforated inner
tube 18 and not into the space between inner tube 18 and outer
shell 20. Inner perforated tube 18 and outer shell 20 have the
noted downstream axial ends 42 and 44 mating at a downstream joint
84 blocking gas flow and sound therepast at outlet 16 such that gas
flow at outlet 16 can only flow from the hollow interior of inner
perforated tube 18 and not from the space between inner tube 18 and
outer shell 20. The upstream axial end of inner perforated tube 18
has first and second different diameter portions 86 and 88, FIG. 3,
and a transition portion 90 therebetween. The diameter of portion
86 is larger than the diameter of portion 88 and mates with outer
shell 20. Transition portion 90 extends radially inwardly from
first diameter portion 86 to second diameter portion 88. The
downstream axial end of outer shell 20 has third and fourth
different diameter portions 92 and 94 and a transition portion 96
therebetween. The diameter of portion 94 is smaller than the
diameter of portion 92 and mates with inner perforated tube 18.
Transition portion 96 extends radially inwardly from third diameter
portion 92 to fourth diameter portion 94.
[0015] The number of ribs 22, 24 equals N, the number of grooves
60, 64 equals N, and in preferred form, N is greater than or equal
to 2, and the number of resonant chambers 26, 28, 30 equals N+1,
and the number of sets of perforations 32, 34, 36 equals N+1. The
ribs 22, 24 have a radial height between inner perforated tube 18
and outer shell 20, which radial height progressively increases
from rib to rib. As seen in FIGS. 3 and 4, the radial height of rib
22 is greater than the radial height of rib 24. The ribs extend
radially outwardly from inner perforated tube 18. Outer shell 20
has the noted plurality of annular grooves 60, 64 axially spaced
from each other and serially axially spaced between inlet 14 and
outlet 16 and radially aligned with and engaging respective ribs 22
and 24. The grooves have a radial depth progressively increasing
from groove to groove in inverse relation to the progression of the
progressively increasing height of the ribs. As seen in FIGS. 2 and
3, the radial depth of groove 64 is greater than the radial depth
of groove 60. The shortest radial height rib 24 engages the deepest
radial depth groove 64. The tallest radial height rib 22 engages
the shallowest radial depth groove 60. This construction
facilitates axial insertion of inner perforated tube 18 into outer
shell 20, and enables such axial insertion without a draft on inner
tube 18.
[0016] In the present method for assembling a resonator, the inner
perforated tube 18 is axially inserted into outer shell 20
(downwardly in FIGS. 1-3). First and second pieces 66 and 68 are
abutted at axially extending abutment lines 70 and 72 to a
pre-assembled condition. The first and second pieces 66 and 68 in
the pre-assembled condition are inserted axially into outer shell
20 such that pieces 66 and 68 are held in assembled condition in
outer shell 20, preferably solely by outer shell 20, without
bonding or welding of pieces 66 and 68 to each other. Radial
retention force is provided by the snap-fit detent engagement of
ribs 22, 24 and detent sealing engagement surfaces 50, 56,
respectively. The noted progressive stepping of the ribs and
grooves facilitates the noted axial insertion, including without
drafting.
[0017] It is recognized that various equivalents, alternatives and
modifications are possible within the scope of the appended
claims.
* * * * *