Folder annotated "Self-regulating mono pump" (23-10-51)

In this document

This page contains only three handwritten inscriptions, with no plan or developed text.

At the top right is the date "23-10-" followed by the number "51" traced over in red p. 1. The same date, "23-10-51", is repeated at the bottom right in pencil p. 1.

At the bottom of the page, an inscription in red ink, in cursive handwriting, mentions "Pompe mono Auto. Regulatrice" followed by the number "51" p. 1. The reading of this mention, however, remains marked as uncertain in the transcription.

No other information — neither diagram, nor nomenclature, nor identifiable signature — appears on this page.

Context

In the early 1950s, Paul Magès was working at Citroën on the principles of the future hydropneumatic suspension, which would notably equip the DS presented in 1955. Pressure regulation systems and associated pumps constituted an important part of this research.

A "self-regulating single-cylinder pump" evokes a component intended to regulate its own flow or pressure, without an external control unit — a technical challenge consistent with the engineer's concerns at that time, although nothing in the document itself details this operation.

Archivist's perspective

By its form — a simple repeated date and a summary title in red ink — this page strongly resembles a cover sheet or divider, intended to identify a file of plans rather than to transmit technical information per se.

It seems probable that it initially preceded or accompanied documents now separated in the digitised archives. Several items dated October and November 1951 deal precisely with a pump and its manufacture, such as the pump plan QM.399 D / E42.401 T with nomenclature dated 29 October 1951, or the plan E401.144c-147c with handwritten observations by Magès, also from 29 October 1951.

The proximity of the dates reinforces the hypothesis that this folder served to group these items, without it being possible to be certain from the content of this page alone.