U.S. patent application number 09/741864 was filed with the patent office on 2001-07-05 for combination of an air filter and a membrane carburetor.
Invention is credited to Bahner, Andreas, Knodler, Bernd.
Application Number | 20010005984 09/741864 |
Document ID | / |
Family ID | 8083498 |
Filed Date | 2001-07-05 |
United States Patent
Application |
20010005984 |
Kind Code |
A1 |
Knodler, Bernd ; et
al. |
July 5, 2001 |
Combination of an air filter and a membrane carburetor
Abstract
The invention relates to the combination of an air filter and a
membrane carburetor (1). The membrane carburetor (1) has an intake
channel section (3) configured in the carburetor housing (2) into
which the fuel-conducting channels (4, 4') open which are fed from
a control chamber (5) of the carburetor housing (2). The control
chamber (5) is separated by a control membrane (6) from the
compensation chamber (7). A compensation channel (11) leads from
the compensation chamber (7) into a flow space (9). A connecting
piece (8) is led into the flow space (9) as a connection of the
intake channel section (3) of the membrane carburetor (1) with the
flow space (9). The compensation channel (11) and the connecting
piece (8) open into the housing (21) on the clean air side (23).
The housing (21) forms the flow space (9). The compensation channel
(11) is guided into the housing (21) via a segment (10) in the
connecting piece (8) to provide a simpler assembly and constructive
configuration of the compensation connection. The opening (15) of
the compensation channel (11) defines a first plane (17). The
opening (16) of the connecting piece (8) defines a second plane
(18). The planes (17, 18) are separated from each other and these
planes preferably intersect.
Inventors: |
Knodler, Bernd; (Winnenden,
DE) ; Bahner, Andreas; (Weinstadt, DE) |
Correspondence
Address: |
Walter Ottesen
Patent Attorney
P.O. Box 4026
Gaithersburg
MD
20885-4026
US
|
Family ID: |
8083498 |
Appl. No.: |
09/741864 |
Filed: |
December 22, 2000 |
Current U.S.
Class: |
55/385.3 ;
261/35 |
Current CPC
Class: |
F02M 17/04 20130101;
F02M 35/10019 20130101; F05C 2225/08 20130101; F02M 35/10196
20130101; Y10S 55/28 20130101; F02M 35/04 20130101 |
Class at
Publication: |
55/385.3 ;
261/35 |
International
Class: |
B01D 046/00 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 24, 1999 |
DE |
299 22 748.0 |
Claims
What is claimed is:
1. A combination of an air filter and a membrane carburetor, the
combination comprising: a carburetor housing defining an air intake
channel through which a stream of air is drawn by suction; said
carburetor housing further defining an interior space; a membrane
partitioning said interior space into a control chamber for holding
fuel and a compensation chamber; fuel-conducting channels extending
from said control chamber and opening into said air intake channel
for conducting fuel from said control chamber to said air intake
channel for entrainment by said stream of air; an air filter
housing defining a flow space; a connecting pipe connecting said
flow space to said air intake channel for conducting said stream of
air from said flow space to said air intake channel and said
connecting pipe having an opening in said flow space where said
stream of air enters said connecting pipe; a compensation channel
for connecting said compensation chamber to said flow space; said
compensation channel including a channel segment within a portion
of said connecting pipe and said channel segment having an opening
in said flow space; said connecting pipe having a wall and a part
of said wall defining a wall of said compensation channel in the
region of said channel segment; and, said openings of said
connecting pipe and said channel segment of said compensation
channel being disposed in said flow space in respectively different
planes.
2. The combination of claim 1, wherein said opening of said
connecting pipe is a first opening defining a first plane and said
opening of said channel segment of said compensation channel is a
second opening defining a second plane; and, said first and second
planes are transverse to each other.
3. The combination of claim 2, wherein said first and second planes
are approximately perpendicular to each other.
4. The combination of claim 1, wherein said opening of said
connecting pipe is a first opening defining a first plane and said
opening of said channel segment of said compensation channel is a
second opening defining a second plane; and, said first and second
planes are at different topographical elevations in said flow
space.
5. The combination of claim 4, said air filter including an air
filter partitioning said flow space into a clean air side and a
dirt side where dirt accumulates; and, said first and second
openings being disposed on said clean air side.
6. The combination of claim 5, wherein said air filter housing is
configured as one piece with at least portions of said connecting
pipe and said compensation channel.
7. The combination of claim 6, wherein said air filter housing is
partitioned into first and second housing parts conjointly defining
a partition plane; said air filter housing defining a support plane
within which said air filter is supported in said air filter
housing; and, said partition plane and said support plane are
approximately parallel to each other.
8. The combination of claim 7, said first housing part being on
said clean side and said second housing part having a wall having
first and second flanges; said carburetor being mounted on said
flanges with said compensation chamber being at said first flange
and said air intake channel being at said second flange; and, said
compensation channel opening into said compensation chamber at said
first flange and said connecting pipe opening into said air intake
channel at said second flange.
9. The combination of claim 5, said air filter housing including
and inner element; and, a section of said connecting pipe and a
section of said compensation channel being formed as one piece with
said inner element.
10. The combination of claim 9, said inner element including a
circularly-shaped base and a cylindrical rim extending from said
base and said rim having a U-shaped configuration when viewed in
section; said second housing part having a circularly-shaped
flange; and, said cylindrical rim engaging over said
circularly-shaped flange of said second housing part.
11. The combination of claim 10, wherein said section of said
compensation channel is a first section thereof and said
compensation channel includes a second section which can be
connected to said first section thereof; said first section is
conically expanded on said circularly-shaped base of said inner
element; and, said second section is in said second housing part
and has a counter cone formed thereon for coming into seal-tight
engagement with said first section.
12. The combination of claim 1, further comprising a diaphragm
mounted at said opening of said compensation channel is said flow
space.
13. The combination of claim 12, said diaphragm being configured as
a separate component.
14. The combination of claim 13, said diaphragm being made of
metal.
15. The combination of claim 14, said diaphragm having an opening
with a diameter of approximately 2 mm.
16. The combination of claim 1, further comprising a flow
straightener mounted in said opening of said connecting pipe in
said flow space.
17. The combination of claim 1, further comprising a muffler
mounted in said opening of said connecting pipe in said flow space.
Description
BACKGROUND OF THE INVENTION
[0001] An arrangement of an air filter and a carburetor is
disclosed in German patent publication 2,902,348. The membrane
carburetor includes an arrangement for compensating for pressure
fluctuations of the ambient pressure on the fuel-filled control
chamber of the carburetor. A compensation chamber is arranged on
the dry rear side of the control membrane. The compensation chamber
communicates with a compensation channel which branches from a flow
compartment at atmospheric pressure. With this arrangement, a
reliable operation of the engine is ensured. The combustion air
flows through the intake channel section of the membrane carburetor
into the combustion chamber of the engine. This combustion air
mixes with fuel entering into the intake channel section from the
control chamber. In this way, an underpressure develops in the
control chamber whereby the control membrane is moved and a control
valve is opened via which fuel flows into the control chamber.
Fluctuations of the ambient pressure operate via the compensation
chamber on the control membrane so that more or less fuel is
metered in dependence upon ambient air pressure. An overmetering or
undermetering of fuel into the intake channel of the membrane
carburetor is thereby avoided. The known arrangement is large and
is complex to assemble.
SUMMARY OF THE INVENTION
[0002] It is an object of the invention to configure the
compensation of a membrane carburetor in a simple manner in an
arrangement of air filter and membrane carburetor so that the
degree of contamination of the air filter is considered while, at
the same time, facilitating a simple manufacture and assembly. The
air filter is connected ahead of the membrane carburetor.
[0003] The invention is for a combination of an air filter and a
membrane carburetor. The combination includes: a carburetor housing
defining an air intake channel through which a stream of air is
drawn by suction; the carburetor housing further defining an
interior space; a membrane partitioning the interior space into a
control chamber for holding fuel and a compensation chamber;
fuel-conducting channels extending from the control chamber and
opening into the air intake channel for conducting fuel from the
control chamber to the air intake channel for entrainment by the
stream of air; an air filter housing defining a flow space; a
connecting pipe connecting the flow space to the air intake channel
for conducting the stream of air from the flow space to the air
intake channel and the connecting pipe having an opening in the
flow space where the stream of air enters the connecting pipe; a
compensation channel for connecting the compensation chamber to the
flow space; the compensation channel including a channel segment
within a portion of the connecting pipe and the channel segment
having an opening in the flow space; the connecting pipe having a
wall and a part of the wall defining a wall of the compensation
channel in the region of the channel segment; and, the openings of
the connecting pipe and the channel segment of the compensation
channel being disposed in the flow space in respectively different
planes.
[0004] A simple assembly of the compensation unit is possible
because of the configuration and arrangement of the compensation
channel in the connecting piece between the intake channel section
of the membrane carburetor and the flow space. The compensation
channel opens into the housing, especially the air filter housing.
This housing forms the flow space. Because of this constructive
measure, a part of the wall of the connecting piece simultaneously
forms a wall of the compensation channel. The housing, which forms
the flow space, is purposefully partitioned by an air filter
element. The respective openings of the connecting piece and the
compensation channel lie on the clean air side of the flow space.
The connecting piece extends through the air filter element
together with the compensation channel guided therein. The air
filter element and a filter carrier for accommodating the air
filter element are thereby only penetrated at one location.
[0005] The plane defined by the opening of the compensation channel
lies in a plane other than the plane defining the opening of the
connecting piece itself. Preferably, the planes of both openings
are arranged at different elevations or are perpendicular to each
other. In this way, it is ensured that no dynamic pressure is
present at the opening of the compensation channel. Instead, static
pressure is present at this opening.
[0006] With increasing contamination of the air filter, the
underpressure increases on the clean air side of the housing during
operation of an internal combustion engine supplied by the membrane
carburetor. In this way, the problem of an overenrichment of an
air/fuel mixture is present. To counter this problem, the
underpressure of the clean air side of the flow space or of the
housing is present on the dry side of the control membrane via the
compensation channel and operates in a compensating manner on the
control membrane of the membrane carburetor. This leads to the
situation that the air/fuel mixture remains substantially constant
in the mixture ratio even when contaminants have accumulated on the
air filter.
[0007] If the opening of the compensation channel is arranged in
the flow space at a different topographical elevation to the
opening of the connecting piece for the combustion air, the opening
of the compensation channel can be placed in a peripheral region of
the housing defining the flow space. In this way, it is ensured
that only static pressure is present at the opening of the
compensation channel.
[0008] It can be purposeful to configure the connecting piece and
the compensation channel as one piece with the housing defining the
flow space. To exchange an air filter element, the housing is
partitioned into two housing parts in the plane in which the air
filter element is mounted or is partitioned into two housing parts
in a plane parallel thereto. The compensation channel and the
connecting piece can preferably be configured as one piece with an
interior element of the air filter housing and extend through the
air filter at one location.
[0009] The interior element is, in plan, preferably circularly
shaped with a cylindrical rim. The cylindrical rim is configured so
as to have a U-shape when viewed in section and engages over a
corresponding annular flange of a flow space in the air filter
housing part which is connected to the output channel section of
the membrane carburetor so as to permit flow. The base of the
circularly-shaped interior element supports a cylindrically-shaped
end section of the connecting piece. The end section projects the
same distance to both sides. The end section of the compensation
channel extends through the base of the interior element in the end
section of the connecting piece and this end section of the
compensation channel opens in a widening cone on its inner side in
the region of the base. In the assembled condition of the interior
element, the end section of the compensation channel sits with the
cone on a conical connecting end of the compensation channel in the
air filter housing. In this way, a tight separation between the
compensation channel and the connecting piece is ensured.
[0010] The free end of the compensation channel on the support
element is provided with a diaphragm arranged at the opening of the
compensation channel. The diaphragm has a central, preferably
circular, opening. The diaphragm is advantageously made of metal
and can be seated in the opening of the compensation channel.
Different diaphragms make possible the adaptation of the
compensation device to different kinds of membrane carburetors. If
the central opening is to be very accurate, the diaphragm is
preferably made of metal, especially as a turned piece.
[0011] It is purposeful to provide flanges at the outer side of the
air filter housing for connecting the compensation channel and the
connecting piece. The seal of the sealing surfaces at the flanges
is assumed by profile seals or roll rings made of elastic
material.
[0012] At the opening of the connecting piece in the flow space, it
is advantageous to fix a flow straightener, such as a lattice, for
the purpose of attenuating the noise of the air sounds in the
connecting piece. The flow straightener is advantageously so
configured that it subdivides the clear cross section of the
connecting piece into the intake channel and the compensation
channel.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013] The invention will now be described with reference to the
drawings wherein:
[0014] FIG. 1 is a schematic representation of an arrangement of an
air filter and a membrane carburetor together with a compensation
channel and connecting piece;
[0015] FIG. 2 is a side elevation view of a part of an air filter
housing having flanges for the compensation channel and the
connecting piece;
[0016] FIG. 3 is a plan view of the housing in FIG. 2;
[0017] FIG. 4 is a plan view of a flow straightener for use in the
opening of the connecting piece;
[0018] FIG. 5 is a view of the flow straightener of FIG. 4;
[0019] FIG. 6 is a view, in longitudinal section, of an embodiment
of the arrangement of the invention of an air filter and a membrane
carburetor;
[0020] FIG. 7 is an exploded view of the arrangement of FIG. 6;
[0021] FIG. 8 is a longitudinal section taken through a housing
inner element having a diaphragm in the compensation channel;
[0022] FIG. 9 is a view, in longitudinal section, taken through a
housing inner element having a seated diaphragm on the compensation
channel;
[0023] FIG. 10 is a longitudinal section through a housing inner
element with a diaphragm of metal in the opening of the
compensation channel;
[0024] FIG. 11 is a plan view of a further flow straightener for
use in the opening of the connecting piece; and,
[0025] FIG. 12 is an axial section through the flow straightener of
FIG. 11.
DESCRIPTION OF THE PREFERRED EMBODIMENTS OF THE INVENTION
[0026] The arrangement shown in FIG. 1 with a membrane carburetor 1
is for an internal combustion engine in a portable handheld work
apparatus such as a motor-driven chain saw, cutoff machine,
brushcutter or the like. An intake channel section 3 with a
throttle flap 34 is provided in the carburetor housing 2. The
membrane carburetor 1 has a membrane fuel pump 35 integrated into
its housing 2. The drive chamber of the fuel pump 35 is charged via
a pump channel 36 with the pressure, which is present in the
crankcase of the engine, and the membrane carburetor is mounted on
the engine. The membrane pump 35 draws fuel via a check valve 37
from a fuel tank (not shown) and pumps this fuel via a second check
valve 38 into a control chamber 5 in the carburetor housing 2 of
the membrane carburetor 1. The entry channel 39 into the control
chamber 5 is controlled by a control valve 40 which is controlled
by the control membrane 6 delimiting the control chamber 5. From
the control chamber 5, the fuel reaches the intake channel section
3 via the valve sections and the fuel conducting channels (4,
4').
[0027] A connecting piece 8 in the form of a pipe is fixed at the
input 41 of the intake channel section 3. The pipe is angled at
90.degree. to the longitudinal axis 42 of the intake channel
section 3. The connecting piece 8 is guided into a housing 21 which
defines a flow chamber 9 for the inducted ambient air. The filter
and filter carrier 22 arranged in the housing 21 partition the
clean air side 23 from the contamination side 23' of the housing.
When the engine is running, the combustion air 43 flows via the air
filter element of the filter carrier 22 to the clean air side 23 of
the air filter and via the throttle flap 34 to the combustion
chamber of the engine. Because of the generated underpressure, fuel
is drawn by suction via the fuel conducting channels (4, 4') as a
consequence of the configuration of the intake channel section 3 as
a venturi whereby an ignition capable air/fuel mixture is
introduced into the combustion chamber of the engine.
[0028] The pressure in the control chamber 5 drops because of the
fuel entering into the intake channel section 3 whereby the control
membrane 6 is moved into the control chamber 5 and a control valve
40 is opened via an angle-shaped lever acting at the center of the
control membrane 6 so that fuel can flow in to compensate the
underpressure in the control chamber 5. A compensation chamber 7 is
provided in the carburetor housing 2 on the side of the control
membrane 6 facing away from the control chamber 5. The compensation
chamber 7 is connected via a compensation channel 11 to the clean
air side 23 of the housing 21. In this way, it is achieved that,
for an increased degree of contamination of the air filter 22, the
underpressure, which builds up on the clean air side 23, operates
on the control membrane in the compensation chamber 7 and thereby
prevents too much fuel from being metered because of the high
underpressure. The air/fuel mixture, which is supplied to the
combustion chamber of the engine, is thereby not overenriched.
[0029] In order to configure the compensation of the membrane
carburetor in a simple manner, it is provided that the compensation
channel 11 and the connecting piece 8 are brought together over a
distance 10 of the wall 13 of the connecting piece 8. As shown in
FIG. 1, the component region 12 of the wall 13 of the connecting
piece 8 forms a wall section of the compensation channel 11. The
opening 15 of the compensation channel 11 determines a plane which
is separate from the plane determined by the opening 16 of the
connecting piece 8.
[0030] It is advantageous to arrange the openings of the
compensation channel 11 and of the connecting piece 8 so that they
lie facing away from each other and the planes 15 and 16 assume
approximately right angles to each other. With the aid of this
constructive measure, it is ensured that only static pressure is
present at the opening 15 of the compensation channel 11; whereas,
at the opening 16 of the connecting piece 8, a dynamic pressure is
present when the engine is running. The topographical elevation 19
of the opening 15 of the compensation channel 11 in the housing 21
is thereby greater than the topographical elevation 20 of the
opening 16 of the connecting piece 8.
[0031] As FIG. 6 shows, advantageously clear differences are
present between the topographical elevations. With this spatial
separation of the two openings (15, 16) it is ensured that the
dynamic pressure at the opening 16 of the connecting piece 8 has no
influence on the static pressure at the opening 15 of the
compensation channel 11 while the engine is running. The connecting
piece 8 and the compensation channel 11 extend through the filter
carrier 22 as shown in FIG. 1. The filter carrier 22 partitions the
housing 21 into a clear air side 23 and into a contamination side
23'. The openings 15 and 16 are arranged on the clean air side 23
of the housing 21.
[0032] FIG. 2 shows a side view of a part 25 of the air filter
housing having flanges for the compensation channel 11 and the
connecting piece 8. The housing 21, which is shown in FIG. 1,
defines the flow chamber 9. The housing 21 is partitioned in a
plane 29 which is parallel to or identical with the center plane 28
of the air filter carrier 22 (FIG. 1). The side view toward the
part 25 of the housing 21 shows in FIG. 2 that the flanges 26 and
27 on the wall 32 of the housing for the compensation channel 11
and the connecting piece 8 are formed by planar surfaces of the
part 25. The diameter of the compensation channel 11 is smaller by
a multiple than the diameter of the intake channel 44 of the
connecting piece 8. Bores 52 are arranged on the opposite-lying
sides of the intake channel 44 for fixing the membrane carburetor
to the housing part 25. Threaded bolts can be guided through the
bores 52.
[0033] The connecting piece 8 ends in an opening 16 above the plane
29. The opening 16 of the connecting piece 8, when viewed in
section, is configured as a circular segment with a flat wall
segment 45. The flat wall segment 45 defines a partition wall
between the connecting piece 8 and the compensation channel 11. A
flow straightener 33 for attenuating noise of the combustion air 43
is introduced into the opening 16 of the connecting piece 8. The
flow straightener 33 is in the form of a lattice-like toothed
plate. It can also be advantageous to configure the flow
straightener 33 so that it extends over the distance 10 in FIG. 1
in the connecting piece 8 and the flow straightener 33 with its
flat wall segment 45 over the distance 10 forms a wall of the
compensation channel 11.
[0034] FIG. 3 shows a plan view of the housing part 25 shown in
FIG. 2. A sealing surface 46 is provided over the entire rim of the
housing part 25. This sealing surface 46 serves as a sealing mount
for the part 24 of the housing 21 which is shown in FIG. 1 and for
accommodating the filter carrier 22. The connecting piece 8 opens
approximately centrally in the center of the housing part 25 (FIG.
3). The connecting piece 8 is shown as a cylindrical pipe in the
illustrated embodiment. The compensation channel 11 is guided in
the connecting piece 8 with a small offset V of the longitudinal
axis 47 of the compensation channel 11 to the longitudinal axis 42
of the connecting piece 8. The compensation channel 11 has a cross
section corresponding to a segment of a circle over the distance 10
in FIG. 1. On the one hand, the wall 13 of the connecting piece
and, on the other hand, the flat wall 45 of the flow straightener
33 define the boundary surfaces of the compensation channel 11.
This constructive measure effects the condition that the
compensation channel 11 and the intake channel 44 are guided
together in the connecting piece 8 at least in the region whereat
they pass through the filter carrier. The configuration and
assembly of the air filter housing itself is simplified because the
filter carrier 22 is penetrated only at one location.
[0035] FIG. 4 is a plan view of a flow straightener 33 at the
opening of the connecting piece 8. The flow straightener 33 has a
cylindrical base body (FIG. 5). A lattice-shaped base plate 49 with
cutouts 48 is mounted at one end of this cylindrical base body. The
diameter (d) of the flow straightener corresponds approximately to
the inner diameter of the connecting piece 8. The flow straightener
33 is seated in the connecting piece 8. The flow straightener 33
partitions the compensation channel 11 from the clear cross section
of the connecting piece 8 with its flat wall 45. In this way, the
flat wall 45 of the flow straightener 33 and the wall of the
connecting piece 8 conjointly define the compensation channel 11
over the length L (FIG. 5).
[0036] FIG. 5 shows a longitudinal section through the flow
straightener shown in FIG. 4. The flat wall 45 of the flow
straightener 33 delimits a cylindrically-shaped base body of length
L. One end of the cylinder segment is formed by the base plate 49
having corresponding cutouts 48 as shown in FIG. 4. The base plate
49 can have a bore 50 for fixing the flow straightener in the
connecting piece 8.
[0037] FIG. 6 shows a further embodiment of an arrangement of an
air filter and a membrane carburetor with compensation. The same
components have the same reference numerals as in FIGS. 1 to 5. In
FIG. 6, the plane 29 is coincident with the center plane 28 of the
filter carrier 22. The housing 21 defines the flow space 9 and is
partitioned at plane 29 into a housing part 25 facing toward the
membrane carburetor 1 and a housing part 24 facing away from the
membrane carburetor. An inner element 51 is mounted between the
housing parts 24 and 25 for supporting the filter carrier 22. A
component piece 54 of the compensation channel 11 and a component
piece 53 of the connecting piece 8 are formed as one piece in the
inner element 51. The component pieces have a tubular shape and
define a fluid connection between the clean air side 23 of the
housing 21 for the intake channel section 3 and the compensation
space 7, respectively, of the membrane carburetor 1. As shown, the
topographical elevation 19 of opening 15 of the compensation
channel 11 is more than twice as large as the topographical
elevation 20 of the opening 16 of the support piece 8. The opening
15 of the compensation channel 11 is thus mounted in the peripheral
region of the flow space 9 of the housing 21. With this
constructive measure, it is ensured that only static pressure is
present at the opening 15 of the compensation channel 11.
[0038] FIG. 7 shows an exploded view of the arrangement of the air
filter and of the membrane carburetor 1 in FIG. 6. The housing 21
forms the flow space 9 and is partitioned into two housing halves
at plane 29. The membrane carburetor 1 is mounted on the one
housing half 25. In the embodiment shown, the other housing half 24
is, at the same time, a housing part, for example, of a
motor-driven chain saw. A filter carrier is provided between the
two housing parts (24, 25) for supporting an air filter element.
The filter carrier covers the inner element 51. The inner element
51 has a circular disc-shaped base 55. A rim 56 is formed as one
piece on the base 55 and has a U-shaped cross section. The rim 56
faces toward the housing part 25. A part piece or end piece 53 of
the connecting piece 8 and a part piece or end piece 54 of the
compensation channel 11 is formed as one piece from the base 55 of
the carrier element 51. When the cylindrical rim 56, which has a
U-shaped cross section, engages over the rim of a cylindrical
flange 57, which is configured in the housing part 25, then the
intake channel section 3 and the compensation space 7 of the
membrane carburetor 1 are connected to the part piece or end pieces
(53, 54), respectively, so as to permit fluid flow. For this
purpose, the end piece or component piece 54 of the compensation
channel 11 is expanded conically at the base 55 of the carrier
element 51 and comes into seal-tight contact against a countercone
58 of the compensation channel 11 in the housing part 25. The
opening 15 of the compensation channel 11 on the opposite-lying end
of the conical expansion is provided with a diaphragm 59. The
diaphragm 59 includes a circularly-shaped opening 16.
[0039] FIGS. 8 to 10 show longitudinal sections through the carrier
element 51 with differently configured diaphragms 59 at the opening
15 of the component piece 54 of the compensation channel 11. The
diaphragm 59 can be pressed as a cylindrical component with a stop
61 into the opening 15 of the component piece 54 (see FIG. 8). It
can be purposeful to push the diaphragm 59 as a sleeve-shaped
component over the component piece 54 at the opening 15 of the
compensation channel 11 (see FIG. 9). Preferably, the diaphragm 59
is made of plastic. However, if a high accuracy of the opening 60
of the diaphragm 59 is required, then the diaphragm is made of
metal, for example, as a metal turned part and is fixed from the
inside into the component piece 54 of the compensation channel 11
at the opening 15 thereof (see FIG. 2). The component piece 54 is
configured in the interior to be conical.
[0040] The embodiment of an intake sound silencer or flow
straightener of FIGS. 11 and 12 corresponds to that of FIGS. 4 and
5 in its basic configuration. For this reason, the same parts are
identified by the same reference numerals. The cylindrically-shaped
base body 65 of the insert includes a flat wall 45 on its periphery
which has a roof section 67 on its rim 66 facing away from the base
plate 49. The roof section 67 lies outside of the base body 65 and
preferably drops off slightly.
[0041] As FIG. 11 shows, the roof section 67 extends over the
entire length of the rim 66 and juts out far from the wall 45 so
that the opening 15 of the compensation channel 11 is essentially
overlapped. The compensation channel 11 is guided in the connecting
piece 8. The cover section 67 has a spacing (v) to the opening 15
so that the opening 15 can communicate with the clean air side 23
of the air filter. The roof section 67 ensures that essentially
only static pressure is present at the opening 15 because the plane
18 of the air entry to the opening 15 lies transversely to the
opening 16 of the connecting piece 8 and faces away from the
latter.
[0042] It is understood that the foregoing description is that of
the preferred embodiments of the invention and that various changes
and modifications may be made thereto without departing from the
spirit and scope of the invention as defined in the appended
claims.
* * * * *