Commercial motor vehicles employ auxiliary braking systems known as retarders to assist in controlling vehicle speed and reducing service brake wear. Match each type of retarder to its corresponding operating mechanism.
- Engine Compression BrakeOpens cylinder exhaust valves near top dead center of compression, releasing compressed air so it cannot drive pistons down.
- Exhaust RetarderRestricts the flow of gases through the exhaust system, generating backpressure that slows the engine pistons.
- Hydraulic RetarderIntroduces fluid into a chamber with opposing fixed and rotating vanes, using fluid friction to retard driveline rotation.
- Electric RetarderApplies electromagnetic eddy currents around the driveshaft or axle to produce opposing magnetic resistance.
Answer
Engine Compression Brake pairs with releasing compressed air via cylinder exhaust valves; Exhaust Retarder pairs with restricting exhaust gas flow to create backpressure; Hydraulic Retarder pairs with utilizing fluid friction in a vaned chamber; Electric Retarder pairs with generating electromagnetic eddy currents around the driveshaft.
Each of the four commercial vehicle retarders utilizes a distinct mechanical principle to slow the vehicle: engine compression brakes vent compressed air to eliminate the power stroke; exhaust retarders build backpressure by restricting exhaust gas evacuation; hydraulic retarders use fluid friction across opposing rotor/stator vanes; and electric retarders use electromagnetic eddy currents around the driveshaft or drive axle.
Step-by-Step Solution
Key Concept
Distinction among the four primary types of commercial vehicle retarders (engine compression, exhaust, hydraulic, and electric) and their mechanical operating principles.
Estimated Time:1m 30s