User's Manual

212
UHB800-CAM
GLOSSARY OF TERMS
Push Rod: A rod, protruding from a brake chamber, which is connected to the arm of a slack adjuster via a
clevis pin.
Q Brake: Quick-change, Rockwell’s term for brake design with an open anchor pin rib. Interchanges with Spicer
FC design.
Q Plus: Rockwell’s term for a quick-change design brake shoe using thicker than standard lining.
R12: Pilot control air valve with quick dump
R14: Pilot control air valve with quick dump and anti-compounding
REB: Eaton’s new 15” design Reduced Envelope Brake.
Replace-A-Brake: Spicer’s term for a kit to service one brake assembly. It includes two new lined brake shoes
and the necessary anchor pins, rollers, springs, etc.
Retarder: Auxiliary brake device: engine brake, exhaust brake, hydraulic retarder or electric retarder.
Return Springs: Springs which retract brake shoes upon release of the brake actuator valve.
RFI: Radio frequency interference
Roll Over: A term denoting that an s-cam has traveled beyond its designed stopping position during brake
application.
RP: Recommended practice
SAE: Society of Automotive Engineers
SAP: Single Anchor Pin, Eaton’s term for brake design utilizing one non-replaceable anchor pin per brake
assembly.
S-cam Brake: A type of brake where mechanically induced rotation of an S shaped cam forces brake linings
against the brake drum.
Scored Drum: Brake drum with a grooved friction surface, resulting in excessive lining wear. Severe scoring
requires that a drum be machined, within manufacturer’s limits, before replacing the linings.
Service Brakes: As opposed to parking brakes, that portion of the brake system used for normal brake applica-
tions.
Slack Adjuster: A lever, connecting the brake push rod with the foundation brake camshaft, which provides
torque to rotate the brake camshaft when the brake treadle is depressed. Used only on cam-actuated brakes, it
also provides a means of adjusting clearance between the brake shoes and the drum to compensate for lining
wear. Some models are automatic, requiring proper installation procedures and requiring periodic inspection to
insure proper functioning. Manual slack adjusters require proper installation and manual adjustment at mainte-
nance intervals.
SLR: Static loaded radius