Citroën Design Office work programmes (1945): suspension, starters and Fressard works

In this document

This file brings together seven handwritten sheets from the Citroën Design Office, each written on a standard "SOCIÉTÉ ANONYME ANDRÉ CITROËN" form, listing work in progress or to be carried out.

Miscellaneous problems (p. 24)

These include the TPV transmission shaft (awaiting endurance tests in the laboratory), the TPV screw jack (two solutions ordered, completed on 16/5/45) and the Burke anti-reverse freewheel (spring awaiting measurement, with an associated test programme).

Rubber starter (p. 25)

The page details a test programme for the rubber starter: torque tests according to angles, flexibility measurements, endurance tests, tests on the TPV car, and a literature search on rubber. A second section concerns the direct starter: engine tests, ignition advance variation, search for the best gear ratio, cold tests, and study of a roller freewheel (jamming/unjamming slope, max torque, fatigue).

Suspension component tests (p. 26-27)

These sheets detail a highly structured test programme on the suspension: static sealing of cylinder seals, sliding force control, flexibility measurements of the cylinder and air bell according to inflation, "gymnastics" tests (wear, heating, damping), bell pressure holding, and tests on the levelling electro-valves (flow measurement, time constants). Page 27 covers a similar programme for the suspension cylinder (test rigs to be drawn, seal endurance, comparison of torsion benches) and the suspension housings (differential pistons, interaction valves, flexibility change).

Fressard works (p. 28-30)

Under the handwritten name "Fressard", a list of tasks marked with a cross (X): mounting the direct starter on the engine then on the TPV car, section of the brake metering valve, tests of metering rollers of different diameters, rack jack, modification of the "Crosley" screw jack for the TPV, hydraulic transmission test without seal, wear tests of graphite brake pads, friction coefficient of Ferodo washers. The date "13/3" appears in the margin p. 28. Pages 29-30, more difficult to read, mention an assembly at "Bourg", TPV tests "on the bench and in a cold chamber", and a new test of a roller freewheel.

Context

In 1945, Citroën was preparing the launch of what would become the 2 CV, then designated internally as "TPV" (Toute Petite Voiture). Paul Magès, who joined Citroën in August 1925 and was then deputy head of Super-Control (autobiographical notes), was already developing there — from his plans of 17 February 1944 — the principles of the hydropneumatic suspension that would later equip the DS, presented on 6 October 1955.

The "starters" mentioned refer to the engine starting systems (spring or rope/rubber), an alternative solution to the classic electric starter, economical and adapted to a post-war popular vehicle marked by restrictions.

Archivist's perspective

This file illustrates, on the scale of a month of work at the design office in 1945, the diversity of projects carried out simultaneously by Magès' team: suspension, starting components, braking. The pages devoted to the suspension p. 26-27 show a test method that was already very rigorous — flexibility measurements, seal endurance, control of electro-valves — which prefigures the protocols used a year later on the first tests of the 2 CV with hydropneumatic suspension (May-July 1946).

The name "Fressard" p. 28 undoubtedly identifies a collaborator or technician in charge of executing this work, but his exact role remains unspecified by the document.

These sheets usefully complement the 1945 manufacturing schedule, by showing the level of operational detail that preceded the start of manufacturing.