Rotation-actuated drum brake
OwnerKan Cui, Margaret C. Liu +1inventors
InventorsKan Cui, Margaret C. Liu, Samuel K. Liu
Life of this patent
Estimating the term…
Abstract
The rotation-actuated drum brake uses both inner and outer sets of brake shoes, which are actuated in a radial manner, to contact the inner and outer surfaces of a cylindrical brake drum. The inner and outer sets of brake shoes are disposed within an annular brake housing and are constrained to move radially. An actuator selectively drives rotation of a rotating disc having a plurality of arcuate slots defined therein. This drives roller guides of the inner and outer sets of brake shoes to roll within respective ones of the arcuate slots. The driven rolling of the roller guides drives the radial motion of the inner and outer sets of brake shoes to simultaneously frictionally engage the inner and outer surfaces of the cylindrical brake drum.
Claims17
A rotation-actuated drum brake, comprising:
- an annular brake housing having at least one outer bore defined therein;
- a circular divider wall mounted in the annular brake housing defining an interior chamber and an exterior chamber within the annular brake housing, the circular wall having a central opening, at least one inner radially extending slot, and at least one outer radially extending slot defined therein, the central opening having an annular rim extending within the interior chamber, the annular rim having at least one inner bore defined therein;
- at least one inner brake shoe disposed in the interior chamber of the brake housing, the at least one inner brake shoe having a shaft, a convex braking surface and a roller guide, the roller guide including a pin extending orthogonal to the shaft and through the at least one inner radially extending slot in the circular wall and a freely rotatable roller mounted on the pin in the exterior chamber, a portion of the shaft of the at least one inner brake shoe being slidably disposed in the at least one inner bore defined in the annular rim;
- at least one outer brake shoe disposed in the interior chamber of the brake housing, the at least one outer brake shoe having a shaft, a concave braking surface and a roller guide, the roller guide including a pin extending orthogonal to the shaft and through the at least one outer radially extending slot in the circular wall and a freely rotatable roller mounted on the pin in the exterior chamber, a portion of the shaft of the at least one outer brake shoe being slidably disposed in the at least one outer bore in the brake housing;
- a rotating disc disposed within the exterior chamber of the annular brake housing, the rotating disc having:
- at least one arcuate inner slot defined therein, the roller of the at least one inner brake shoe being disposed in the at least one arcuate inner slot to roll therein;
- at least one arcuate outer slot defined therein, the roller of the at least one outer brake shoe being disposed in the at least one arcuate outer slot to roll therein;
- and
- a central opening defined therein aligned with the central opening in the circular divider wall;
- a rotor sleeve adapted for mounting on a wheel, the rotor sleeve having an annular flange extending into the interior chamber in the brake housing between the at least one inner brake shoe and the at least one outer brake shoe, the annular flange having an inner surface and an outer surface;
- and
- an actuator mounted on the annular brake housing for driving rotation of the rotating disc with respect to the annular brake housing, selective rotation of the rotating disc driving the at least one inner brake shoe to frictionally engage the inner surface of the annular flange of the rotor sleeve with the convex braking surface, and simultaneously driving the at least one outer brake shoe to frictionally engage the outer surface of the annular flange of the rotor sleeve with the concave braking surface in order to stop rotation of the wheel.
Dependencies are inferred from the claim text.