Improvements to pumps: Paul Magès' inertial suction valve (18 July 1964)

In this document

Description of the invention (p. 43)

The handwritten note by Paul Magès, titled "Perfectionnement aux pompes" (Improvements to pumps), describes a pump equipped with two valves. The delivery valve is described as "classic": it opens under the pressure created by the piston and closes under the effect of a spring combined with the pressure difference p. 43.

The suction valve is presented as "the main feature of the invention". Unlike classic valves, which are light and housed in the cylinder body, this one is described as heavy, moving with the piston with a determined longitudinal clearance, and consisting of a ring of the same diameter as the piston sliding in the bore p. 43. According to the text, "the inertia of the valve and its friction in the cylinder allow it to open and close exactly at the necessary moment, regardless of the piston's operating frequency" p. 43.

The document also mentions an elastic capacity placed at the pump inlet to limit pulsations in the suction pipe: a rubber sleeve surrounding the pump body, serving as a connection to the reservoir, "whose shape and elastic characteristics are determined to obtain the sought result" p. 43. The text explicitly refers to drawing E 59 801 p. 43, while the following page refers to a drawing E 39 8001 p. 44 — both formulations coexist in the transcriptions.

Associated pages

Page 44, which is very difficult to read, uses the same title "Perfectionnement aux pompes" but its textual content is largely illegible; only the mention of a drawing and two signatures dated 18.7.64 and 21.7.64 remain, the latter addressed to someone named "Etiévant" (uncertain reading) p. 44.

Page 45 is the technical drawing E 39.800/-, dated 5-8-64, bearing the name "MOLLER" (uncertain reading) in the title block and a partially legible designation referring to a "cylinder" p. 45. Page 42, which is very difficult to read, bears an annotation "Pompe mono" and the date 18-07-64 p. 42.

Context

At Citroën, in the 1960s, Paul Magès continued to refine the hydraulic components born with the DS (1955), notably the high and low-pressure pumps that power the hydropneumatic suspension and other assisted circuits. This continuous work on improving valves and anti-pulsation systems is part of this general logic of increasing reliability, although this context remains external to the document itself.

Archivist's perspective

This note illustrates, it seems, a fairly detailed phase of research into pump engineering: Magès details an original principle — the use of the inherent inertia of a heavy valve to synchronise its movement with that of the piston — presented as the central innovation p. 43. The carefully written text, dated and signed twice (18.7.64, then validated on 21.7.64), suggests a document intended to formalise an invention for filing or internal transmission, completed about a fortnight later by the detailed drawing of 5 August 1964 p. 45.

This file can be compared with other older pieces from the same collection dedicated to Citroën hydraulic pumps, such as the technical note on the self-regulating pump with accumulator (1949) or the drawing of the DS high-pressure pump no. E 401.8444 (1958), which testify to the continuity of Magès' work on these essential components over the years.