Park brake lock mechanism with enhanced locking
View Patent ↗A park brake assembly includes a base. A park brake lever is pivotal about the base. A pawl is pivotal about a pawl pivot. The pawl is linked to the brake lever. A sector is attached to the base and the pawl releasably locks and unlocks relative to the sector. The pawl includes a pivot slot that receives the pawl pivot and wherein the pawl translates about the pawl pivot changing an angle of engagement of the pawl relative to the sector when subjected to a force.
1. A park brake assembly comprising:
a base;
a park brake lever pivotal about the base;
a pawl pivotal about a pawl pivot, the pawl linked to the brake lever;
a mounting bracket attached to the brake lever and rotatable about a pivot pin attached to the base;
a sector attached to the base, the pawl releasably locking and unlocking relative to the sector;
the brake lever including a rod connected to an actuator for actuating the park brake assembly and a spring member contacting the pawl at one end of the spring member and contacting the mounting bracket at another end of the spring member biasing the actuator and biasing the pawl about the pawl pivot and into engagement with the sector;
wherein the pawl includes a pivot slot that receives the pawl pivot and wherein the pawl translates about the pawl pivot changing a contact of the pawl relative to the sector when the sector exerts a force upon the pawl when there is a friction force between the pawl and sector preventing the pawl from entering the sector.
2. The park brake assembly of claim 1 wherein the rod is further coupled to the pawl.
3. The park brake assembly of claim 1 wherein the sector includes a plurality of teeth formed thereon for receiving at least one tip of the pawl.
4. The park brake assembly of claim 3 wherein the at least one tip of the pawl includes only one tip.
5. The park brake assembly of claim 3 wherein the at least one tip of the pawl includes multiple tips.
6. The park brake assembly of claim 1 wherein the pawl translates from a first pivot axis to a second pivot axis relative to a pivot center.
7. The park brake assembly of claim 6 wherein the first pivot axis changes relative to the second pivot axis in an angular shift wherein a half lock condition is prevented.
8. The park brake assembly of claim 6 wherein the first pivot axis changes relative to the second pivot axis in an angular shift of less than 0.1 millimeters.
9. The park brake assembly of claim 1 wherein the pivot slot has a size larger than the pawl pivot providing a clearance allowing a specified translation.
10. The park brake assembly of claim 1 wherein the pawl slot includes a shape providing a clearance allowing a specified translation.
11. The park brake assembly of claim 10 wherein the pivot slot has an ovoid shape.
12. The park brake assembly of claim 1 wherein the pawl pivot includes a shape providing a clearance allowing a specified translation.