Every single car or truck on the highway is equipped with a parking brake, a hand brake, an e-brake, or an emergency brake. Irrespective of the identify, the parking brake is engineered to nutritional supplement the most important hydraulic braking system and hold the auto still when the vehicle is turned off and parked. In an unexpected emergency, it may also be used to gradual the car to a halt.
Common parking brakes acted on the rear wheels. They were mechanically operated by a long cable routed from the rear brakes to a tiny pedal in the footwell or to a hand lever — very easily accessible by the driver. Physically pushing the pedal or firmly pulling on the lever place stress on the cable that squeezed the pads (on disc brakes) or shoes (on drum brakes) in opposition to the brake rotor or drum, successfully stopping the rear wheels from rotating.
Regardless of being a clear-cut and efficient design, cable-actuated parking brakes experienced a number of disadvantages. 1st, a driver could inadvertently depart the parking brake partly engaged and generate away. This would have on down the brake pads, triggering the brakes to be ineffective. Second, pulling the parking brake at pace would lock up the rear wheels, maybe initiating a skid (and a likely spin). And finally, cable-actuated brakes expected upkeep as the cable stretched, and lubrication was wanted to keep them functioning smoothly.
In recent a long time, automakers have replaced the cable-actuated parking brake with an electronic parking brake (EPB). An EPB is digitally actuated through a tiny button or swap on the dashboard or console. When activated, an digital management unit (Ecu) indicators an actuator motor to set the parking brake reducing any actual physical exertion by the driver.
Automakers are employing two forms of EPBs in late-product vehicles. The 1st is a “cable and puller” system, a hybrid of new and outdated engineering. Just set, it replaces the passenger cabin’s compact pedal or hand brake with an electrical actuator that puts stress on the cable. As an alternative of having a extensive thick cable jogging from the cabin to the rear wheels, a smaller electrical wire is applied to set off the actuator.
The second type of EPB is a “caliper-integrated” method. This is a additional sophisticated process, as the cable to the rear brakes is eradicated. Rather, a tiny electric powered motor (servo) is placed at each and every brake caliper to lock just about every wheel separately. The caliper-built-in program offers automakers adaptability as they really don’t have to stress about cables running as a result of the chassis. In addition, the caliper-integrated procedure could be programmed to release the brake mechanically when the car is place in push or reverse or set the brake when the transmission is set into park. It can also include a “hill hold” element, which retains the brakes to reduce rollback if the vehicle is on a steep incline.
Automakers have embraced EPBs due to the fact the cable-free of charge layout lets them track down the parking brake handle pretty much anyplace on the dashboard or console. And zero exertion is expected to actuate them — just a basic press or pull of a button or change. In addition, innovative electronics on the car will inform the driver and prevent the auto from moving if the parking brake is engaged.
And do not get worried, as EPBs may perhaps also be made use of in emergencies just like their handbook predecessors. If the primary brakes are not performing, pulling (and holding) the digital parking brake swap — even while the auto is moving down the road — will automatically engage large skid-absolutely free braking and bring the automobile to a end!