Parking brake

In road vehicles, the parking brake, also known as a hand brake or emergency brake (e-brake), is a mechanism used to keep the vehicle securely motionless when parked. Historically, it was also used to help perform an emergency stop should the main hydraulic brakes fail. Parking brakes often consist of a cable connected to two wheel brakes, which is then connected to a pulling mechanism. In most vehicles, the parking brake operates only on the rear wheels, which have reduced traction while braking. The mechanism may be a hand-operated lever, a straight pull handle located near the steering column or a foot-operated pedal located with the other pedals. In road vehicles, the parking brake, also known as a hand brake or emergency brake (e-brake), is a mechanism used to keep the vehicle securely motionless when parked. Historically, it was also used to help perform an emergency stop should the main hydraulic brakes fail. Parking brakes often consist of a cable connected to two wheel brakes, which is then connected to a pulling mechanism. In most vehicles, the parking brake operates only on the rear wheels, which have reduced traction while braking. The mechanism may be a hand-operated lever, a straight pull handle located near the steering column or a foot-operated pedal located with the other pedals. In vehicles with automatic transmissions, the parking brake was originally intended for emergency stopping (for instance, if the foot brake completely failed due to a loss of hydraulic pressure or other malfunction). As safety regulations became stringent in the 1980s, and modern brake systems became more reliable (using dual-circuit hydraulics and low-brake-fluid sensors), modern brakes no longer cause emergencies in normal contexts; a brake warning light appears on the dashboard if there was a problem. It is no longer as necessary for a driver to use this brake for emergencies, although if it were to be used, the parking brake lever should be slowly engaged to help reduce speed. While most automatic transmission vehicles have parking brakes, it is often not engaged by drivers when parking. However, it is recommended to use it, as the parking pawl in the gearbox could fail due to stress or another vehicle striking the car, causing the car to roll. Also, regular use of the parking brake reduces the chance of corrosion by keeping the cables in-motion. In manual transmission vehicles, the parking brake must always be engaged to keep the vehicle stationary. When parking on an uphill gradient, it is recommended that the front wheels face away from the curb. This would prevent the car from rolling into the roadway should the parking brake fail. Similarly, on a downhill gradient, the front wheels should face the curb for the same reason. In a manual transmission, leaving the car in first gear (or in reverse if pointing downhill) is also advised, as the engine will prevent the car from rolling if the parking brake fails.The parking brake in most vehicles is still completely mechanical. Traditionally engaged by pulling a lever, the cables manually engage part of the car's braking system, usually the rear disk or drum brakes. The mechanical nature allows the driver to apply the brake even if the main hydraulic brake system fails. In manual and automatic transmission vehicles, the parking brake can also used for various driving situations which require the vehicle to be momentarily stopped. For example, the brake can be engaged when moving off an uphill slope, as this allows the driver to hold the accelerator and clutch pedals steady without the vehicle rolling backwards. Other common situations is when the vehicle is stopped at a traffic light, a pedestrian crossing, or simply waiting to turn in front of oncoming traffic. The parking brake would ensure the car is secure, should another vehicle come into physical contact from behind, causing the car to jolt forward. It is not recommended to use the parking brake when the vehicle is in-motion, unless there is a problem with the main brakes, as this can lock the back wheels and cause a skid. This is known as a handbrake turn, which is often performed in street racing and off-road rally racing to initiate rear wheel drift. The position of the parking brake differs between vehicle models and manufacturers. However, a universal feature is either one or two of the warning lights which appear on the dashboard when the parking brake is engaged. The most common placement of the parking brake is in the center console of the vehicle, in between the driver and front passenger seats. Operating the brake is performed by pulling the lever up (which is connected to a ratchet) until there is tension. To disengage the brake, the button is held while simultaneously pulling the lever up to disengage the ratchet and then pushed all the way down with the button still held. In older vehicle models, a stick lever may be used instead which is located under the instrument panel.