Handwritten notes and sketches: engine, clutch, foot controls

In this document

Page 24: mechanical sketches and figures

The page presents two pencil sketches. The first, top left, depicts a cylindrical mechanism (wheel or flywheel seen in profile) connected to a horizontal axis, with an articulated part suggesting a cam or a spring lever; the annotation "moteur" (engine) accompanies the whole, as well as an uncertain word read as "elicoïdale" (helical).

The second sketch, below the first, shows a linear assembly: a sawtooth shape near the word "moteur", a housing with two circular holes under an uncertain word ("alarme"), and a series of lamellae or a leaf spring under a cut-off inscription "disq-".

At the bottom of the page are columns of numbers and fractions (for example "11B", "51 / 60", "0'60", "2''6", "150 60", "1200", "600 T", "40t"), arranged in three columns with underlining, which seem to correspond to calculations or dimensions p. 24. The word "suspension" appears uncertainly among these notes p. 24.

Page 25: mechanism and foot controls

This technical sketch shows a hatched part topped by the letter "E", crossed by an articulated arm pivoting on an axis. Below, two rectangular shapes frame a central area with vertical rods, a coil spring and a circle marked with a "+" sign. A sinuous outline encompasses the bottom of the page, suggesting a casing or bodywork; a housing with wire connections appears on the right, as well as elbow pipes and a lever equipped with a small wheel or thumbwheel p. 25.

Vertical numerical inscriptions ("09", "009", "0009") followed by a "V" appear at the top right, with letters "E" and "D" and "+"/"-" signs near the central circle, suggesting a direction of current or movement p. 25.

An uncertain inscription suggests a "Pédale frein" (brake pedal), and another, very fragmentary, seems to mention a lever ("8 pd- pa levier Ch+ Vd...") p. 25.

Context

At Citroën, in the 1930s, studies on transmission components (clutch, gearbox) and foot controls (brake pedal, in particular) were part of the routine work of the design offices, in parallel with more prospective research on suspension.

These notes are part of a period when the engineer Paul Magès, before becoming famous for the invention of the hydropneumatic suspension (which would equip the DS in 1955), worked on various mechanical subjects related to the automobile — engine, clutch, braking — without it being possible here to establish a direct and dated link with these later developments.

Archivist's perspective

These two pages belong to a set of very rough working sketches, where diagrams of mechanisms (engine, clutch, braking) and numerical figures whose exact meaning escapes non-specialized reading are mixed p. 24-25.

The uncertain mention of "suspension" p. 24 invites caution: it could link this document to Magès' more advanced research on this theme, but nothing in the transcriptions allows this to be stated with certainty.

It seems that these sheets are part of the same corpus of workshop notes as other items in the collection, such as the handwritten folder "1933" listing technical studies, which attests to similar work on speeds and injection during the same period. In the absence of an explicit date on these two pages, their precise insertion into the chronology of Magès' work remains uncertain.