Method of improving rotor vibration control and resulting rotor

Details Method of improving rotor vibration control and resulting rotor Method of improving rotor vibration control and resulting rotor

1998-04-22

2001-02-13

Oberleitner, Robert J. (Department: 3613)

Brakes

Elements

Brake wheels

C188S2640AA

Reexamination Certificate

active

06186292

ABSTRACT:

BACKGROUND OF INVENTION
The present invention relates to a method of reducing the noise of a vehicle brake rotor and specifically for manipulating the rotor hat cross vents to tune the resonant frequency of the rotor.
Wheeled vehicles are typically slowed and stopped with a braking system that generates frictional forces. Many braking systems include a rotor attached to one or more of the vehicle wheels for rotation therewith, and a caliper assembly secured to a non-rotating component of the vehicle, such as the vehicle frame. A typical rotor includes an annular peripheral section having friction surfaces disposed on opposite sides and a central hat section having fasteners for securing the wheel thereto. The caliper assembly includes a pair of brake pads disposed adjacent the rotor friction surfaces, and a moveable piston operatively connected to one or more of the brake pads. When the driver brakes the vehicle, hydraulic or pneumatic forces move the piston which clamps the pads against the friction surfaces of the rotating rotor. As the brake pads press against the moving rotor friction surfaces, frictional forces are created which oppose the rotation of the wheel and slow or stop the vehicle.
The frictional braking forces generate heat which is absorbed by the rotor, increasing the temperature of the rotor. It is important to dissipate the heat and cool the rotor, because excessive rotor temperatures reduce braking performance, creating longer stopping distances, shortening the life of the rotor, or even causing brake failure. Rotors are commonly cooled using moving air which absorbs the heat from the rotor and carries it away. It is known to “ventilate” the rotors by forming holes or vents through the friction surfaces or the hat section of the rotor. As the rotor turns, air is moved through the vents. The moving air absorbs heat and cools the rotor.
During braking, the brake pads excite the rotor when contacting the friction surfaces, causing the rotor to vibrate. The rotor is excited by other stimuli, such as the vehicle drive train components, which also transmit energy to the rotor causing it vibrate. The vibrating rotor creates undesirable noise by transmitting the vibrations to vehicle occupants through the surrounding air or through the structure of the vehicle. The rotor may also excite other components, causing them to vibrate and emit undesirable noise. It is desirable to reduce vibrations of the rotor or change the frequency of these vibrations in order to reduce undesirable noise from the rotor and adjacent vehicle components.
SUMMARY OF INVENTION
This invention relates to a method of reducing the noise created by a vehicle rotor by adjusting the natural or resonant frequency at which the rotor tends to vibrate, and to the resulting rotor. The resonant frequency is moved away from the frequencies of excitation of such sources as the brake pads and vehicle drive train components. The resonant frequency of the rotor is adjusted by manipulating the geometry and mass of the rotor by adjusting the number, size, shape, spacing and location of cooling vents formed in the hat section of the rotor.


REFERENCES:
patent: 3661235 (1972-05-01), Harrison
patent: 4379501 (1983-04-01), Hagiwara et al.
patent: 4469203 (1984-09-01), Herbulot et al.
patent: 4523666 (1985-06-01), Murray
patent: 4705146 (1987-11-01), Tarter
patent: 4867284 (1989-09-01), Okamura et al.
patent: 5238089 (1993-08-01), Matsuzaki et al.
patent: 5492205 (1996-02-01), Zhang

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