Self-adjusting parking brake actuator
AssigneeVentra Group Inc.
InventorMichael Sykes
Life of this patent
Estimating the term…
Abstract
A self-adjusting parking brake actuator for a vehicle is provided having an eccentrically-mounted self-adjust cam assembly. The cam assembly is mounted eccentrically to the lever axis to provide a variable mechanical advantage during actuator stroke. The eccentric offset for the self-adjusting cam is less than the outside radius of the cam to reduce the overall space requirements of the actuator.
Claims20
A lever mechanism for applying tension to a cable, said lever mechanism comprising:
- (a) a bracket;
- (b) a lever assembly, said lever assembly rotatably mounted to said bracket about a lever axis for rotation between a first position and a second position;
- (c) a position lock adapted to releasably lock said lever assembly in said second position;
- (d) a cam member adapted to connect to a cable, said cam member rotatably mounted on said lever assembly for rotation about a cam axis, said cam member having a radius about said cam axis, said cam axis offset from said lever axis by a distance less than said cam member radius;
- (e) a spring adapted to rotatably bias said cam member in a direction tending to increase tension in a cable connected to said cam member, said spring extending between said cam member and said lever assembly;
- and
- a clutch assembly mounted on said lever assembly said clutch assembly being actuatable to selectively prevent rotation of said cam member relative to said lever assembly, said clutch assembly adapted to actuate upon rotation of said lever assembly.
A mechanism for variably tensioning a vehicle parking brake cable, said mechanism comprising:
- (a) a bracket;
- (b) a lever mounted to said bracket and rotatable about a lever axis between a brake-released position and a brake-applied position;
- (c) a position lock adapted to releasably lock said lever in said brake-applied position;
- (d) a cam member rotatably mounted to said lever about a cam axis, said cam being adapted for connection to a parking brake cable and having a cable guide adapted to receive said parking brake cable, said cam member being spring-biased to rotate towards said brake-applied direction, said cam axis being spaced apart a distance from said lever axis;
- and
- (e) a clutch mounted on said mechanism, said clutch being adapted to fix said cam member relative to said lever when said lever is moved out of said brake-released position,
- wherein the distance in a normal direction from said lever axis to said cam axis is less than the radial distance from said cam axis to said cable guide.
A vehicle parking brake actuator for variably tensioning a brake cable comprising:
- (a) a bracket;
- (b) a lever rotatably mounted to said bracket, said lever rotatable about a lever axis, said lever rotatable between a brake-release position and a brake-apply position, said lever axis defining an axial direction;
- (c) locking means for releasably maintaining said lever in said brake-apply position;
- (d) self-adjusting cam means for connection to said brake cable, said selfadjusting cam means rotatably mounted to said lever about a cam axis, said cam axis being spaced apart from said lever axis in a direction normal to said lever axis a distance less than said cam radius;
- (e) biasing means for rotatably biasing said self-adjusting means relative to said lever in a brake-apply direction;
- and
- (F) clutch means for selectively preventing rotation of said self-adjusting means relative to said lever.
Dependencies are inferred from the claim text.