Steering column
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![](http://upload.wikimedia.org/wikipedia/commons/thumb/b/be/Steer_system.jpg/220px-Steer_system.jpg)
1 Steer;
2 Steering column;
3 Pinion;
4 Steer arm;
5 Fusee
![](http://upload.wikimedia.org/wikipedia/commons/thumb/4/49/Steering_column.jpg/220px-Steering_column.jpg)
2 case
3 Steering column (hidden by the case - blue dashed line)
4 Universal joint
The automotive steering column is a device intended primarily for connecting the steering wheel to the steering mechanism.
Secondary functions[]
A steering column may also perform the following secondary functions:
- energy dissipation management in the event of a frontal collision;
- provide mounting for: the multi-function switch, column lock, column wiring, column shroud(s), transmission gear selector, gauges or other instruments as well as the electro motor and gear units found in EPAS and SbW systems;
- offer (height and/or length) adjustment to suit driver preference
Steering lock[]
Modern vehicles are fitted with a steering lock which is an anti-theft device. It is fitted to the steering column usually below the steering wheel. The lock is combined with the ignition switch and engaged and disengaged either by a mechanical ignition key or electronically from the vehicles electronic control unit. These locks were introduced on many General Motor products in 1969 drastically reducing thefts of these GM models,[1] and on Ford, Chrysler, and AMC products in 1970.
Collapsible column[]
A common device to enhance car safety is the collapsible steering column. This is designed to collapse in the event of a collision to protect the driver from harm. The column can collapse after impact with a tolerance ring inserted between the inner shaft of the steering column and the external housing. The wavelike protrusions on the circumference of the tolerance ring act as a spring to hold the two parts in place in normal driving conditions. At a specific level of force, for example in the event of a collision, the tolerance ring allows the inner shaft to slip inside the housing, so the column can collapse, absorbing energy from the impact.[2]
In virtually all modern vehicles, the lower section of the inner shaft is articulated with universal joints which helps control movement of the column in a frontal impact, and also gives engineers freedom in mounting the steering gear itself.
Regulatory requirements[]
In the United States, steering columns are governed by several federal regulatory requirements, notably FMVSS 108, 114 and 208. The Chinese directive GB15740- 2006 obligates Chinese car manufacturers to incorporate anti-theft mechanisms in their vehicles.[3] European Union Commission Directive 95/56/EC (1995) mandates all cars exported to European markets must be fitted with anti-theft security devices. This regulation also requires that a steering lock must be able to withstand forces of 100Nm applied to the steering wheel without failing.[4]
References[]
- ^ "The Popular Science Anti-Car-Theft Device Competition" Popular Science", July 1969, p.70.
- ^ "Collapsible Steering Column Relies on Tolerance Rings". Machine Design. Retrieved 2017-03-10.
- ^ "GB 15740-2006 English version, GB 15740-2006 Protective devices against unauthorized use of motor vehicles (English) - Code of China". Code of China. Chinese Government. Retrieved 2017-03-10.
- ^ "EUR-Lex - 31995L0056 - EN - EUR-Lex". eur-lex.europa.eu. Retrieved 2017-03-10.
- Auto parts
- Mechanisms (engineering)
- Automotive steering technologies