Patent ID: 7552627

Claim:
A brake wear measurement apparatus for use on a brake assembly equipped with a wear pin having a diameter, and an exposed height, comprising: a plunger sleeve having a first end and a second end, wherein said second end has a spring stop, and wherein said plunger sleeve first end has an inner diameter, wherein said plunger sleeve first end inner diameter is greater than the wear pin diameter; a plunger having a first end and a second end, wherein said plunger is slidably mounted in said plunger sleeve, and wherein said plunger first end is exposed, such that when said brake wear measurement apparatus is placed over the wear pin, the wear pin contacts said plunger first end, and moves said plunger within said plunger sleeve; a plunger stop, wherein said plunger stop prevents said plunger from exiting said plunger sleeve; a plunger spring mounted in said plunger sleeve, against said spring stop, wherein said plunger spring acts on said plunger, such that when there are no other external forces on said plunger, said plunger spring forces the plunger against said plunger stop, such that said plunger first end is flush with said plunger sleeve first end; and, a locking mechanism, such that if a force is applied to said plunger first end, thus compressing said plunger spring, and forcing said plunger to retract within said plunger sleeve, said locking mechanism will lock said plunger in such retracted position.