Vehicle pillar
Carrying vehicle pillars , which connect the roof area (roof and inner side parts) with the body substructure ( sill , floor front / rear), are designated with letters running from front to back - regardless of the side of the vehicle:
- In automotive engineering, the A-pillar is the connection between the vehicle roof and the front bulkhead .
- The B-pillar is the connection between the vehicle floor and the vehicle roof in the middle of the passenger cell. Some coupes and convertibles and, very rarely, sedans do not have a B-pillar.
- The C-pillar is the connection between the vehicle roof and the fenders (rear side wall) on the rear of the vehicle .
- The D-pillar is the fourth pillar in station wagons and vans .
function
In the event of an accident in which the car rolls over, the pillars have the life-sustaining role of stabilizing the passenger cell against vertical deformation. Much more important is the absorption of forces in a side impact so that the vehicle occupants remain unharmed. In racing and off-road vehicles, as well as coupés and convertibles, which often only have two or one column, they are partially supported by particularly stable roll bars , which sometimes only snap up automatically when needed. Cabriolets have a particularly reinforced A-pillar.
In the area of the roof pillar, which connects the A, B and C pillars, head airbags can be integrated in current passenger cars , which are intended to protect the head and shoulder area in the event of a side impact or the vehicle rolling over.
history
For aesthetic reasons, American manufacturers began to “cap” the B-pillar on two-door models at the end of the 1940s. In the mid-1950s, four-door models followed, and shortly afterwards even a few station wagons : only a stump remained from the column to the lower edge of the window. Most of the time, this stump carried the heavy rear door, which was less often hung at the back (“ suicide door ”); then the lock latch did not click into the pillar, but into the sill. The windows of the front and rear doors closed with a rubber sealing lip (usually attached to the rear window). The exterior of the column itself disappeared completely behind the door leaves . The result was more elegant lines and a visually flatter vehicle ( hardtop ).
In the 1960s, safety requirements made it necessary to reinforce the roofs, which, however, were accepted - given the generally higher vehicle masses and low gasoline prices in the USA anyway. In Europe, on the other hand, the capped B-pillar could not establish itself in multi-door vehicles. The reason for this lies not only in safety concerns, but also in the higher demands on the gap size precision of the doors.
literature
- Hans-Hermann Braess, Ulrich Seiffert: Vieweg manual automotive technology. Friedrich Vieweg & Sohn Verlagsgesellschaft mbH, Braunschweig / Wiesbaden 2001, ISBN 3-528-13114-4 .