192 clutches and power-stop control – Vortex-flow drive and clutch – Including drive-lockup clutch
Reexamination Certificate
2000-06-30
2001-09-04
Luong, Vinh T. (Department: 3682)
192 clutches and power-stop control
Vortex-flow drive and clutch
Including drive-lockup clutch
C192S070170, C192S070160, C074S572200, C074S574300
Reexamination Certificate
active
06283262
ABSTRACT:
BACKGROUND OF THE INVENTION
1. Field of the Invention
This invention generally relates to a rotary portion, which has a flexible plate to be flexible in a bending direction. More specifically, the present invention relates to flywheel assemblies and torque converters in which a dynamic damper is coupled thereto to absorb vibrations.
2. Background Information
A flywheel is usually installed in an engine of a car to prevent rotary fluctuations at the low speed range of the engine. In the flywheel, a clutch device and a ring gear are usually installed. The engine generates a driving power by converting the combustion force generated by combustion of the fuel into a torque that rotates a crankshaft. At that time, a bending force is exerted on the crankshaft when the engine converts the combustion force into a torque that rotates a crankshaft. The crankshaft is then bent by the combustion, resulting in a bending vibration on the flywheel in a bending direction. The reaction force from the vibration of the flywheel is transmitted to the engine block, which further vibrates the body of the car via the engine mount. This results in a considerable amount of noise during acceleration of the engine.
In order to reduce noise during acceleration of the speed of the engine, the flywheel is connected to the crankshaft by a flexible plate. The flexible plate is usually a thin disk-shaped member or a thin cross-shaped member, which has a high rigidity in the direction of rotation and a low rigidity in the direction of the bending vibrations. When bending vibrations are transmitted, the flexible plate absorbs the vibrations by bending in the bending direction (generally axially), resulting in a reduction of vibrations on the flywheel.
As shown in
FIG. 5
, a vibrational characteristic of a conventional flywheel is illustrated. The dotted line of
FIG. 5
represents a characteristic of a flywheel assembly in which the flywheel is fixed directly to the crankshaft without a flexible plate. The solid line of
FIG. 5
represents a characteristic of a flywheel assembly which has a flexible plate coupled between the flywheel and the crankshaft.
In the characteristic of the dotted line (without a flexible plate) shown in
FIG. 5
, the resonance frequency exists within a normal range A. In the characteristic of the solid line (with a flexible plate ) shown in
FIG. 5
, the resonance frequency is divided into two sections. Both sections of resonance frequencies have a vibration level (bending angle of a flywheel) which is lower than the resonance frequency of the characteristic of the dotted line (without flexible plate). In addition, the two sections of resonance frequencies are shifted into high and low frequency sides from a normal range A, respectively. Thus, by shifting the resonance frequencies from the normal range A, noise can be reduced during acceleration of the speed of the engine.
However, in the characteristic of the solid line (with flexible plate) of
FIG. 5
, the resonance frequency on the low frequency side sometimes remains in a normal range A. In that case, nevertheless, the noise is caused during acceleration of the speed of the engine. An object of the present invention is to reduce a noise in accelerating the speed.
In view of the above, there exists a need for flywheel assemblies and torque converters with dynamic dampers which overcome the problems in the prior art devices. This invention addresses these needs in the prior art as well as other needs, which will become apparent to those skilled in the art from this disclosure.
SUMMARY OF THE INVENTION
One object of the present invention is to provide a flywheel assembly with a dynamic damper to reduce engine noise during accelerating the speed of the engine.
According to one aspect of the present invention, a flywheel assembly is adapted to be coupled to a crankshaft of the engine, and includes a flywheel, a flexible plate and a dynamic damper. The flexible plate connects the flywheel with the crankshaft so as to be able to oscillate in a bending direction. The dynamic damper includes a mass body and an elastic body, which connects the mass body with the flywheel so as to be able to oscillate in a bending direction. Since this flywheel assembly combines the flexible plate with the dynamic damper, in accelerating the speed it can reduce a noise more efficiently than a flywheel assembly which has only a flexible plate. Because the dynamic damper can reduce a vibration around the resonance frequency of the bending vibration which remains in the normal range.
Another object of the present invention is to provide a torque converter with a dynamic damper to reduce engine noise during acceleration of the engine.
According to another aspect of the present invention, a torque converter is adapted to be coupled to a crankshaft of the engine, and includes a torque converter main body, a flexible plate and a dynamic damper. The flexible plate connects the torque converter main body with a crankshaft so as to be able to oscillate in a bending direction. The dynamic damper includes a mass body and an elastic body which connects the mass body with the torque converter main body so as to be able to oscillate in a bending direction.
Since this torque converter combines the flexible plate with the dynamic damper, during acceleration of the engine, it can reduce noise more efficiently than a torque converter which has only a flexible plate. Because the dynamic damper can reduce vibrations around the resonance frequency, the bending vibration remains in the normal range.
Other objects, advantages and salient features of the present invention will become apparent to those skilled in the art from the following detailed description, which, taken in conjunction with the annexed drawings, discloses preferred embodiments of the present invention.
REFERENCES:
patent: D. 402995 (1998-12-01), Hakamata
patent: 4791829 (1988-12-01), Fukushima et al.
patent: 4871342 (1989-10-01), Boss et al.
patent: 5097721 (1992-03-01), Umeyama
patent: 5191810 (1993-03-01), Craft et al.
patent: 5216798 (1993-06-01), Sterling
patent: 5226756 (1993-07-01), Takahashi et al.
patent: 5323665 (1994-06-01), Rediker, Jr.
patent: 5337867 (1994-08-01), Kirkwood
patent: 5355747 (1994-10-01), Kajitani et al.
patent: 5465635 (1995-11-01), Kono et al.
patent: 5788037 (1998-08-01), Forsyth et al.
patent: 5799766 (1998-09-01), Link et al.
patent: 5836217 (1998-11-01), Sudau et al.
patent: 5979594 (1999-11-01), Doman
patent: 3222119 (1983-10-01), None
patent: 0 571 008 A2 (1999-11-01), None
patent: 58151734 (1983-10-01), None
patent: 6411453 (1989-01-01), None
patent: 11-311309 (1999-11-01), None
Exedy Corporation
Luong Vinh T.
Shinjyu Global IP Counselors, LLP
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