Ladder frame

A pre- WWI De Dion with a ladder frame

Frame cranked over the axles with cross bracing and perforated reinforcement plates ("X-frame")

Box frame ( Land Rover Series III)

A ladder frame is a type of vehicle frame in the automotive industry that includes the axles, engine, transmission and body. Several cross struts are inserted between two strong longitudinal spars, giving it the shape of a ladder. To improve torsional rigidity, ladder frames are made from closed profiles. They are then also called box frames .

Until the 1950s, most cars were delivered with frames of this type, after which the self-supporting body prevailed there. Since then, ladder frames have mainly been used to build trucks , trailers , buses and off-road vehicles .

commercial vehicles

In trucks and trailers, the two longitudinal spars are usually straight through, the cross bracing in a ladder or X-shaped design. The side members are made with inwardly lying U-profiles. With these, the center of thrust is on the outside, forces can be introduced via brackets mounted there without twisting the profile. The cross members are U or hat profiles, and gusset plates are attached at critical points. The traverses are riveted, welded or screwed.

Passenger cars

Before the First World War, individual manufacturers began to lower the ladder frame between the axles (low or low frame) or under the axle ( underslung frame) in order to lower the center of gravity and enlarge the interior space. This type of construction became widely accepted in the 1920s.

In the case of luxury vehicles, it was common for the customer to purchase only the chassis with chassis and drive from the manufacturer and to have their own body made by body manufacturers ( wheelwright ).

In the 1960s these manufacturers largely disappeared, and in 1978 the last vehicle was made by Ateliers Henri Chapron .

Off-road vehicle

Some off-road vehicles are still built with a ladder frame today:

• Jeep Wrangler
• Land wind X6 , X9
• Mercedes-Benz G-Class
• Mitsubishi Pajero
• Mahindra Thar
• Nissan Patrol
• Nissan Navara and its derivatives Renault Alaskan and Mercedes-Benz series 470 (X-Class)
• Suzuki Jimny
• Toyota Hilux
• Toyota Land Cruiser
• SsangYong Rexton
• Volkswagen Amarok

Web links

Commons : lead frames  - collection of images, videos, and audio files

Wiktionary: Ladder frame  - explanations of meanings, word origins, synonyms, translations

• There are still real SUVs (Badische Nachrichten)

Individual evidence

1. ↑ ^{a b} Heribert Braun, Günter Kolb: Lkw. A textbook and reference work. 11th edition. Kirschbaum Verlag, Bonn 2012, ISBN 978-3-7812-1850-5 .
2. ^ Bosch: Kraftfahrtechnisches Taschenbuch 10th edition 1950, Robert Bosch GmbH Stuttgart, p. 192.
3. ^ Rolf Gscheidle et al .: Expertise in automotive technology . 27th edition, Verlag Europa-Lehrmittel, Haan-Gruiten, 2001. ISBN 3-8085-2067-1 . P. 432.