AMORTISSEUR DE VIBRATIONS POUR MOTEURS A COMBUSTION INTERNE

VIBRATION DAMPENER FOR INTERNAL COMBUSTION ENGINES

Abrégé français

Elément absorbant les vibrations (6a, 6b) situé à l'intérieur d'un évidement annulaire (5, 7) sur le côté de l'ensemble constitué par la bielle (1) et par le chapeau (4) ou, de plus, dans un autre mode de réalisation, entre le palier principal de vilebrequin et les coussinets principaux du vilebrequin. Cet élément absorbant les vibrations est composé, de préférence, de deux pièces (6a, 6b) conçues pour loger dans une partie évidée (5) de la bielle (1) et dans une partie évidée (7) du chapeau (4) afin de faciliter son montage. Cet élément (6a, 6b) absorbe les vibrations entre l'ensemble constitué par la bielle (1) et par le chapeau (4) et le vilebrequin. De même, cet élément (6a, 6b) absorbe les vibrations entre le vilebrequin et le bloc moteur quand il est placé entre le vilebrequin et le palier principal du vilebrequin. Dans des moteurs classiques comportant un ou de multiples cylindres en ligne, cet élément est placé des deux côtés de l'ensemble constitué par la bielle et par le chapeau. Dans des moteurs en V comportant deux bielles contiguës, une de ces bielles possède un élément unique absorbant les vibrations situé sur le côté de contact avec le vilebrequin.

Abrégé anglais

A vibration absorbing member (6a, 6b) is disposed within an annular
recess (5,7) on the side of the connecting rod (1)/ bearing cap assembly (4)
or alternatively/additionally disposed between the crankshaft main bearing and
crankshaft main bearing journal. A vibration absorbing member is preferably
comprised of two pieces (6a, 6b) to fit in a recessed portion (5) of the
connecting rod
(1) and a recessed portion (7) of the bearing cap (4) to facilitate easy
installation.
The vibration absorbing member (6a, 6b) absorbs vibrations between the
connecting
rod (1)/bearing cap assembly (4) and the crankshaft. Similarly the vibration
absorbing member (6a, 6b) absorbs vibration between the crankshaft and the
engine
block when disposed between the crankshaft and the crankshaft main bearing. In
conventional single or multiple in-line cylinder engines the vibration
absorbing
members is disposed on both sides of the connecting rod and bearing cap
assembly.
In V-type engines with two adjacent connecting rods one of the connecting rods
has a single vibration absorbing member disposed on the side of contacting the
crankshaft.

Revendications

Claims
1. A connecting rod for an internal combustion
engine, said connecting rod comprising:
a main rod portion extending from a first end adapted
to be connected to a piston pin to a second end;
a bearing cap connected to said second end of said main
rod portion, wherein said bearing cap and said second end of
said main rod portion together are adapted to be connected
to a rod journal of a crankshaft; said bearing cap and said
second end of said main rod portion each having a recessed
portion together circumscribing said rod journal of said
crankshaft when attached thereto; and
a vibration damper member disposed in said recessed
portions of said bearing cap and said second end of said
main rod portion thereby damping a transmission of
vibrations from said connecting rod to said crankshaft.
2. The connecting rod according to claim 1, wherein
said vibration damper member comprises an O-ring made of an
oil resistant elastomeric rubber material.
3. The connecting rod according to claim 2, wherein
said O-ring is comprised of first and second semi-annular
members, said first member disposed within said recess of
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said second end of said main rod portion of said connecting
rod and said second semi-annular member disposed within said
recess of said bearing cap, said first and second semi-
annular members together substantially circumscribing said
rod journal of said crankshaft.
4. A combination crankshaft and at least one
connecting rod assembly, said crankshaft being adapted to
rotate about a longitudinal axis and having at least one rod
journal longitudinally offset from said longitudinal axis;
said connecting rod being rotatably connected to said at
least one rod journal; said combination comprising:
at least one vibration dampener disposed between said
connecting rod and said crankshaft to dampen a transmission
of vibrations therethrough.
5. The combination according to claim 4, wherein said
at least one vibration dampener comprises at least two
vibration dampeners disposed on opposite longitudinally
outwardly facing sides of said connecting rod.
6. The combination according to claim 4, wherein said
combination comprises two juxtaposed connecting rods
rotatably connected to said at least one rod journal, said
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at least one vibration dampener comprises at least three
dampeners, a first one of said vibration dampeners being
disposed between said two juxtaposed connecting rods and a
second and a third vibration dampener respectively disposed
one each on longitudinally outwardly facing sides of said
two juxtaposed connecting rods.
7. A vibration dampener for an internal combustion
engine, said internal combustion engine comprising:
a crankshaft having at least one rod journal; and
a connecting rod rotatably connected to said at least
one rod journal of said crankshaft;
said vibration dampener comprising an elastomeric
member disposed between said crankshaft and said connecting
rod thereby dampening a transmission of vibrations between
said connecting rod and said crankshaft.
8. A combination crankshaft and at least one main
bearing assembly, said crankshaft having at least one main
bearing journal; said at least one main bearing disposed
about said main bearing journal of said crankshaft and
thereby rotatably supporting said crankshaft to an internal
combustion engine block, said combination comprising:
at least one vibration dampener disposed directly
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between and engaging said main bearing journal of said
crankshaft and said at least one main bearing to
substantially dampen a transmission of vibrations
therethrough.
9. The connecting rod according to claim 1, wherein
said vibration damper member is disposed adjacent a
longitudinally outwardly facing side of said connecting rod.
10. The combination according to claim 4, wherein said
crankshaft further includes a counterweight lobe adjacent
said at least one rod journal, wherein said at least one
vibration dampener is longitudinally disposed between said
counterweight lobe and said connecting rod.
11. The combination according to claim 4, wherein said
at least one vibration dampener is disposed directly between
and engaging said main bearing journal of said crankshaft
and said at least one main bearing to substantially dampen a
transmission of vibrations therethrough.
12. The vibration dampener according to claim 11,
wherein said at least one vibration dampener is made of an
oil resistant elastomeric material.
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13. A vibration dampener for an internal combustion
engine, said internal combustion engine comprising:
a crankshaft having at least one rod journal; and
a connecting rod rotatably connected to said at least
one rod journal of said crankshaft;
said vibration dampener comprising an elastomeric
member disposed directly between and engaging said main
bearing journal of said crankshaft and said at least one
main bearing to substantially dampen a transmission of
vibrations therethrough.
14. The vibration dampener according to claim 13,
wherein said crankshaft of said internal combustion engine
further comprises a counterweight lobe adjacent said at
least one rod journal, and said vibration dampener is
longitudinally disposed between said connecting rod and said
counterweight lobe.
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Description

CA 02302319 2003-03-07
VIBRATION DAMPENER FOR INTERNAL COMBUSTION ENGINES
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention relates to the absorption/isolation of
vibrations in internal combustion engines, and is more
particularly directed to absorbing/isolating harmonic
vibrations between a connecting rod/bearing cap assembly or
crank shaft main bearing assembly and the crankshaft of an
internal combustion engine.
2. Brief description of the prior art
U.S. Patent 5,517,957 discloses a device for damping
torsional vibrations in a drive train connected to an internal
combustion engine. However, the '957 reference to Wagner et
al. is complicated and expensive to manufacture, is bulky and
is located further away from the source of the vibrations.
U.S. patent 4,617,884 also discloses a torsional vibration
isolator. The '884 reference to Allen et al. discloses a
resilient coupling 12 to isolate the flywheel from the crank
shaft. Here again, vibrations isolation is attempted far
away from the source of the vibrations, requires a custom
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crankshaft/flywheel configuration and is expensive to
manufacture.
The isolators of the prior art suffer from the drawback that
they can not be simply incorporated into conventional internal
combustion engine designs, are costly, heavy, bulky and are
located far from the source of the vibrations. The instant
invention is believed to alleviate all of the drawbacks of the
prior art isolators with a simple inexpensive design.
SUMMARY OF THE INVENTION
A vibration absorbing member is disposed within an annular
recess on the side of the connecting rod/bearing cap assembly or
alternatively/additionally disposed between the crankshaft main
bearing and crank shaft main bearing journal. A vibration
absorbing member is preferably comprised of two pieces to fit in
a recessed portion of the connecting rod and a recessed portion
of the bearing cap to facilitate easy installation. The
vibration absorbing member absorbs vibrations between the
connecting rod/bearing cap assembly and the crank shaft.
Similarly, the vibration absorbing member absorbs vibration
between the crank shaft and the engine block when disposed
between the crankshaft and the crankshaft main bearing. In
conventional single or multiple in-line cylinder engines the
vibration absorbing member is disposed on both sides of the
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In re: Decuir, A.
connecting rod and bearing cap assembly. In V-type engines with
two adjacent connecting rods, one of the connecting rods has a
single vibration absorbing member disposed on the side contacting
the crankshaft. The other connecting rod has a vibration
absorbing member disposed on both sides of the connecting rod and
bearing cap assembly. Thus, vibrations are isolated between the
two adjacent connecting rods as well as between the connecting
rods and the crank shaft. The vibration absorbing material is
preferably made of an oil resistant elastomeric rubber material.
BRIEF DESCRIPTION OF THE DRAWINGS
Fig. 1 represents an exploded perspective view of a
connecting rod incorporating the dampener of the present
invention.
Fig. 2 is a perspective view of the assembled device of Fig.
1 according to the present invention.
Fig. 3 is an isolated perspective view of the bearing cap
incorporating the dampener of the present invention.
Fig. 4 is another exploded perspective view of a bearing cap
incorporating the dampener according to the present invention.
Fig. 5 is a perspective assembled view of the bearing cap of
Fig. 4.
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Fig. 6 is a cross sectional exploded view taken along line
6-6 of Fig. 7.
Fig. 7 is an exploded side view of a connecting rod having a
recessed portion adapted to receive the dampener according to the
present invention.
Fig. 8 is a side view of an assembled conventional
connecting rod and bearing cap assembly of the prior art.
Fig. 9 is a cross sectional view taken long line 9-9 of Fig.
8.
Fig. 10 is an exploded cross sectional view taken along line
10-to of Fig. 11.
Fig. 11 is an exploded side view of an alternated connecting
rod and bearing cap incorporating the dampener of the present
invention.
Fig. 12 is an exploded bottom view of two adjacent
connecting rods incorporating the dampener of the present
invention taken along line 12-12 of Fig. 14.
Fig 13 is a bottom view of two adjacent connecting rods
incorporating the dampener of the present invention taken along
line 13-13 of Fig. 15.
Fig 14 is a cross sectional exploded view of two adjacent
connecting rods and bearing caps incorporating the dampener of
the present invention.
Fig. 15 is a cross sectional view of two adjacent connecting
rods and bearing caps incorporating the dampener of the present
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In re: Decuir, A.
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invention.
Fig. 16 is an exploded cross sectional view of two adjacent
connecting rods of an alternate embodiment incorporating the
dampener of the present invention.
Fig 17 is a cross sectional view of the two adjacent
connecting rods of Fig. 16 assembled.
Fig 18 is an exploded bottom view of the two connecting rods
of Fig. 16 taken along line 18-18.
Fig 19 is a bottom view of the two connecting rods of Fig.
17 taken along line 19-19.
Fig. 20 is a side view of two adjacent connecting rods
connected to a crank shaft of a V-type internal combustion
engine.
Fig. 21. is a cross sectional view of two adjacent
connecting rods connected to a crankshaft of a v-type internal
combustion engine and a main bearing journal each incorporating
dampener according to the present invention.
Fig. 22 is an enlarged view of a connecting rod bearing cap
incorporating the vibration dampener of the present invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
To effectively reduce and eliminate the transmission of
harmonic and other vibrations from the connecting rod to the
crankshaft, a vibration dampener member 6a,6b is disposed between
the connecting rod and crankshaft.

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In re: Decuir, A.
Conventionally, the connecting rod which houses the rod
bearings is separated from the crankshaft journal by a thin layer
of lubricating oil. Similarly, the sides of the connecting rod
are bathed in lubricating oil preventing contact with the
crankshaft. Because of the relative incompressibility of this
oil layer, vibrations are easily transmitted from the connecting
rod/bearing assembly to the crankshaft. The arrangement of the
present invention has demonstrated significant reduction in the
transmission of vibrations emanating from the combustion chamber,
which in turn are transmitted to the connecting rod via the
piston. Thus vibrations are prevented/reduced from being
transmitted to the crankshaft and consequently to the remaining
portions of the drive train assembly.
Figure 1 represents an exploded view of the vibration
dampener according to one embodiment of the invention. In this
embodiment a connecting rod 1 has a first end 2 for connection to
a piston pin in a conventional manner. The connecting rod 1
extends to a second end 3 which connects with a bearing cap 4.
The second end 3 of the connecting rod 1 and the bearing cap 4
are secured together in a conventional manner to circumscribe a
journal of a crank shaft.
The connecting rod has a semi-annular recessed portion 5
adapted to receive a semi-annular vibration dampener member 6a.
Similarly, the bearing cap 4 has a semi-annular recessed portion
7 adapted to receive a second semi-annular vibration dampener 6b.
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The two vibration dampeners 6a,6b together form an o-ring like
pad. This vibration dampener is preferably made of a slippery
elastomeric oil resistant rubber material. However, other
vibration absorbent material may be used such as oil resistant
elastomeric plastic or other synthetic materials.
Figure 11 represents a similar connecting rod and bearing
cap assembly comprising oil passages 10 and 11 to facilitate
lubrication between the connecting rod and piston and the
crankshaft. Such an arrangement provides the necessary
lubrication for the embodiments having a dampener disposed on
both sides of the connecting rod.
When the dampener of the instant invention is embodied in
multiple cylinder in-line internal combustion engines, each
connecting rod/bearing cap assembly will comprise a vibration
dampener. Preferably each connecting rod will have two such
vibration dampeners disposed on either side of the connecting
rod.
The vibration dampener of the instant invention may also be
employed in V-type internal combustion engines. Figures 12-15
represent an alternative embodiment of the claimed invention. In
this embodiment, two connecting rod and bearing cap assemblies
are disposed juxtaposed to one another for connection to a single
journal of a crankshaft in a V-type internal combustion engine.
In this embodiment, one of the two connecting rod and bearing cap
assemblies has vibration dampener members 6a, 6b disposed between
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the two assemblies to dampen transmission of vibrations
therebetween.
Figures 16-19 represent a preferred V-type engine vibration
dampener arrangement. In this embodiment, one of two juxtaposed
connecting rod assemblies has a vibration dampener disposed on
opposite sides. The second of the two juxtaposed connecting rods
has just one vibration dampener disposed on the longitudinally
outwardly facing side of the connecting rod with respect to an
attached crankshaft journal. Figure 20 and 21 each depict two
such juxtaposed connecting rod/bearing cap assemblies connected
to a crankshaft journal 13 of a V-type internal combustion
engine. The three vibration dampeners effectively reduce and
nearly eliminate the transmission of vibrations from the
connecting rods to the crankshaft. Here again, oil distributions
passages 10,11 may be employed to facilitate lubrication.
Figure 21 also discloses an additional vibration dampener 15
disposed about the crank shaft main bearing journal 14. In this
embodiment, the vibration dampener 15 is disposed within the main
bearings similarly to the way the vibration dampeners 6a,6b are
disposed within the connecting rod and bearing cap assembly.
Preferably, the vibration dampener 15 is disposed both radially
between the main bearings and the crank shaft's main bearing
journal and between the main bearings and the counter weight lobe
16. This embodiment reduces/eliminates vibrations transmitting
through the crank shaft to the engine block and vice versa.
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While the main bearings are not shown, it is understood that
one of ordinary skill in the art can incorporate the dampener of
the present invention between the main bearing and crank shaft
main bearing journal in a similar fashion to the incorporation of
a vibration dampener in the connecting rod as described above.
Heretofore, no such vibration dampeners have be incorporated
between the main bearings and crank shaft main bearing journal.
Combining a vibration damper 16 between the crank shaft and
main bearing and between the connecting rod and crank shaft has
demonstrated a substantial reduction in harmonic and other
vibrations transmitting through the entire engine and power train
assembly.
While the foregoing invention has been shown and described
with reference to a preferred embodiment, it will be understood
by those possessing skill in the art that various changes and
modifications may be made without departing from the spirit and
scope of the invention.
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Dessin représentatif