The accelerator , technical terminology also drive pedal or the accelerator pedal (just as in the German standard DIN 73001), is a control element of motor vehicles (cars) to which the medium-pressure and thus the motor torque controlled can be. It is located in the footwell of the driver's seat area and is usually operated with the right foot. In motorcycles, in some light vehicles and in motor vehicles that have been individually converted for people with physical disabilities, a throttle twist grip or a hand throttle control element is used instead of the accelerator pedal . Small drivers often use raised pedals .
The term “accelerator pedal” comes from the time of the motor vehicle, in which the air flow through the carburetor , a throttle valve or slide was regulated by means of a cable or linkage with the corresponding pedal . With the introduction of the diesel engine , fuel injection and the electric car , the term has freed itself from its concrete meaning.
Designs and designs
There are two types of construction. The stationary gas pedal is attached to the floor of the car with a hinge, and is usually high and narrow. The associated linkage can either lead downwards into the vehicle floor (rear engine) or upwards (through the bulkhead) into the engine compartment. The smaller hanging accelerator pedal is attached to a lever that always extends from the front and top into the footwell and has its pivot point at the top. In the passenger car range Hanging pedals are usually used; Standing pedals are particularly common in sports cars . With both types, the pedal can be made of metal or plastic; the top side is often provided with longitudinal grooves to prevent the foot from slipping off. Metal pedals with holes are common in racing, they are also offered as a retrofit kit for common cars.
In motor boats , upright gas pedals with a raised rim are used to provide the foot with sufficient lateral support even when the boat is moving. Fixed cable-operated hand levers are used especially for built-in and large outboard motors , which also enable reversing of direction in reversing gears . With small outboard motors, "accelerating" is often done directly on the motor.
In the past, attempts were made to combine the accelerator and brake pedals into one control lever in order to relieve the driver and to cope with the increasing density of traffic. One of the inventors was G. Peiseler from Leipzig with the Peiseler pedal . Such a retrofitted Opel Kadett was accepted by the KTA of the GDR and was in operation in Berlin . The biggest argument in favor of this design is the significantly shorter braking distance to this day, as the foot does not have to be moved and a shocking experience can be converted directly into stretching the leg. For reasons that have not been documented, the gas / brake pedal has not yet been able to establish itself in combustion engines.
Electronic accelerator pedal (e-accelerator pedal)
In newer motor vehicles, the accelerator pedal no longer acts mechanically directly via a linkage or cable, but via the engine control on throttle elements (in gasoline engines ) or on the injection system (in diesel engines ). The sensor that informs the control unit of the driver's gas request is called a pedal value transmitter and is usually a double potentiometer for safety reasons . In newer vehicles, instead of potentiometers, more wear-resistant, but more expensive sensor principles, e.g. B. used with the help of Hall elements . The sensor transmits the accelerator pedal position to the control unit in the form of two voltage values. In the case of a CAN bus network, digital target signals are also implemented.
The traction control can thus relatively easily reduce the engine output.
For people who can no longer operate the gas pedal with their right leg due to paralysis , stiffness or an amputation , this is often relocated to the left next to the brake pedal . In this case, the accelerator and brake pedals are operated with the left leg, while an automatic transmission instead of the manual transmission eliminates the need to operate the clutch .
The accelerator pedal relocation is available in different structural designs, just as different is the retention of the original pedal and / or the ability to quickly switch to “right-hand throttle” or “left-hand throttle” when changing drivers.
The easiest way is to move the accelerator pedal to an extended axle shaft or to a lateral lever arm to the left without replacing it on the right side. There are numerous mechanical solutions with foldable, interchangeable or removable pedals as well as electrically switchable double-pedal solutions for the accompanying retention of the original pedal.
Alternative hand throttle
An alternative solution to motor vehicle retrofitting for physically handicapped people is to convert to a hand throttle control element. The hand throttle is also used regularly or as additional equipment on motorcycles , quads , motor boats and tractors , without an adaptation due to the physical disability.
In some cases, both when relocating the pedal and when installing a hand throttle control, there is a need for a pedal lock that prevents accidental actuation by touching the inactive leg or the leg prosthesis on the original pedal that is still present but currently not required. The pedal lock or “foot throttle lock” consists in the simple case of a permanently or removably attached metal cover.
- Hans-Hermann Braess, Ulrich Seiffert: Vieweg manual automotive technology . 2nd edition, Friedrich Vieweg & Sohn Verlagsgesellschaft mbH, Braunschweig / Wiesbaden, 2001, ISBN 3-528-13114-4
- Kai Borgeest: Electronics in vehicle technology. 1st edition, Friedr. Vieweg & Sohn Verlag, Wiesbaden, 2007, ISBN 978-3-8348-0207-1
- Shorten the stopping distance with the help of the Peiseler pedal . In: Motor vehicle technology 3/1956, pp. 93–95.
- Combined brake-accelerator pedal (Peiseler pedal) . In: Motor Vehicle Technology 5/1960, pp. 177–178.