Multi-stage wet disc brake

Details Multi-stage wet disc brake Multi-stage wet disc brake

1999-06-03

2001-07-24

Oberleitner, Robert J (Department: 3613)

Brakes

Wheel

Axially movable brake element or housing therefor

C188S072700, C188S071500, C188S072400, C192S070150, C192S070230, C192S070251, C192S052100, C192S085060, C192S083000, C192S111400

Reexamination Certificate

active

06264009

ABSTRACT:

BACKGROUND OF THE INVENTION
This invention relates to a wet disc brake assembly having a first stage for reducing the clearance between the discs and a second stage for applying force to the discs to increase the braking torque.
Wet disc brake assemblies are used in vehicles such as lift trucks, front-end loaders and in other devices. Each brake assembly has a disc pack that includes two sets of discs that rotate relative to one another. One set of discs is coupled to a stationary housing, and the other set of discs is coupled to a rotatable member attached to a wheel or some other driven member.
When the brakes are applied by a vehicle operator, a hydraulic piston forces the discs together to increase the friction between them thereby decreasing the relative speed between the sets of discs and slowing the driven member. Typically, clearance must be provided between the discs to minimize parasitic losses resulting from friction between the discs when the brakes are not applied.
More hydraulic fluid is required with greater clearance between the discs. Further, since the piston must travel farther with greater clearance between the discs is used, the brake-apply times inevitably increase.
Therefore, it is desirable to provide a wet disc brake assembly that has a clearance between the discs that results in minimal friction when the brakes are not applied while avoiding increases in the amount of hydraulic fluid necessary or brake-apply times.
SUMMARY OF THE INVENTION AND ADVANTAGES
The present invention provides a multi-stage wet disc brake assembly that has a spindle that defines an axis of rotation. A housing is fixed relative to the spindle and has an inner surface with a plurality of splines. A rotatable member is supported on the spindle and is rotatable about the spindle. The rotatable member has an outer portion with a plurality of splines disposed within the housing opposite the inner surface. First and second sets of friction discs are mounted adjacent to one another in an alternating relationship and have a running clearance between them. The first set of friction discs have an outer perimeter with a plurality of splines in interlocking and sliding relation with the plurality of inner surface splines. The second set of friction discs have an inner perimeter with a plurality of splines in interlocking and sliding relation with the plurality of outer portion splines.
A first actuator is supported within the housing and is moveable toward one of the friction discs. A second actuator coacts with the first actuator and is moveable relative to the first actuator toward one of the friction discs. One of the actuators reduces the running clearance and the other actuator forces the friction discs together to slow rotation of the rotatable member relative to the housing when the rotatable member is being driven.
Accordingly, the above method provides a multi-stage wet disc brake assembly that has one actuator for reducing the running clearance and another actuator for braking the rotatable member so that brake-apply times may be decreased without decreasing the running clearance.


REFERENCES:
patent: 3262531 (1966-07-01), Black et al.
patent: 3869024 (1975-03-01), Hauth et al.
patent: 3927737 (1975-12-01), Prillinger et al.
patent: 3995721 (1976-12-01), Chambers
patent: 4174025 (1979-11-01), Ivachev
patent: 4195714 (1980-04-01), Massing
patent: 4412603 (1983-11-01), Bischoff
patent: 4496033 (1985-01-01), Hall et al.
patent: 4664242 (1987-05-01), Downs
patent: 4974714 (1990-12-01), Goscenske, Jr.
patent: 5072811 (1991-12-01), Everhard
patent: 5603396 (1997-02-01), Murata et al.
patent: 5685399 (1997-11-01), Butler et al.
patent: 5791447 (1998-08-01), Lamela et al.
patent: 2074672 (1981-11-01), None

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