Sheet 11 — Solution A: pedal, lever and accelerator coordination (11 March 1933)

In this document

This sheet, numbered "(11)" and dated "11-3-33" p. 34, explicitly refers to a previous page: "See (10)" p. 34, which shows that it is part of a series of studies.

The "Solution A" table

Magès constructs a three-column table — "Pedal D." (clutch pedal), "levier Ct V" (gear change lever) and "Accela." (accelerator) — to describe the sequence of actions according to driving phases: at a standstill, starting off, shifting to 2nd, shifting into gear, idling, stopping p. 34. The states noted are, for example, "E" (engaged?), "D" (disengaged?), "peu" (little), "Libre" (free), "Emb. proj." (projected engagement?) p. 34 — the precise meanings of these abbreviations are not explained in the document.

The "S" device

A series of notes mentions an element noted "S" whose position evolves: "S is in —", "S remains in — (except throttle […] by minimum regulation)", "S enters in — 5[°] opening increase […] of the increase in engine braking" p. 34. A cross-reference specifies "see S.V. 188 […] 7" p. 34, indicating the existence of another reference document, not attached here.

Braking and automation

Magès envisages a "2-stage braking": "a) throttle closing. b) braking. (a single maneuver)" p. 34, and notes that an "additional throttle controlled by brake pedal" would offer the advantage of "no advance towards […] moment of engine braking" p. 34.

He insists on the fact that gear shifting (3rd→2nd, 2nd→1st) is done "for the sole manner of the clutch and the gear C[hange] lever — without worrying about the accelerator" p. 34, with the mention "2 feet - 2 pedals" p. 34.

A final "Nota" specifies that the hand throttle control is only used in certain cases, with part of the text having been crossed out by the author himself p. 34.

Context

In March 1933, Paul Magès, who joined Citroën in August 1925 at 17 and a half (autobiographical notes), was a young self-taught man within the company; this sheet testifies to his early technical reflection work, long before the major achievements that would mark his career — the TUB braking limiter and joining the design office at the end of the 1930s, then the hydropneumatic suspension from 1944.

In the 1930s, the connections between clutch, gearbox and accelerator relied entirely on the driver's manual and pedal coordination. Research into the "automatic gearbox" or the semi-automation of these controls constituted, for the engineers of the time — including those at Citroën — an important axis of innovation, prefiguring devices that would only reach industrial fruition later in the century.

Archivist's perspective

This sheet probably belongs to a series of systematic studies (the reference "See (10)" and the numbering "(11)" suggest this) where Paul Magès explores, as early as March 1933, a partial automation of driving through the fine coordination of control components p. 34.

The reference to an "S.V. 188" document p. 34 shows that this reflection is part of a larger set of notes, now probably dispersed or not preserved in this collection. This piece is adjacent to other technical study sheets from the same period, such as the handwritten folder "1933" listing ongoing studies, which could provide the overall context for these researches on gears and injection.