Plan P.7245 — Hydrostatic transmission adapted for the GS

In this document

This document is a single, fold-out technical drawing (sheet folded into three panels, landscape format), bearing the reference P.7245 repeated three times at the bottom of the page p. 1.

Plan content

The diagram represents, according to the visual description, a complex mechanical assembly related to a hydrostatic transmission:

• Left panel: two superimposed cross-sectional views of a mechanical housing showing gears, shafts, and bearings, with internal areas tinted pink/magenta, yellow, and light blue to distinguish certain parts or circuits p. 1.
• Central panel: cross-section of an elongated cylindrical element (shaft or cylinder), a longitudinal view of a rectangular part (rail or slide), and a housing pierced with numerous small orifices p. 1.
• Right panel: elevation of a housing with a splined shaft extending towards a striated conical part, and an overall view with a large circular disc with orifices in a circle, evoking a distribution plate or disc p. 1.

Title block

At the bottom right is a partially illegible title block containing a table (indications, dates, initials) and the typewritten mention "NE 202 / 3 000", followed by a line of barely legible text p. 1. No usable date appears in the legible parts.

A black mark (stain or thick line) is visible near the fold, with no determinable meaning p. 1.

Context

The GS, launched by Citroën in 1970, is particularly known for its hydropneumatic suspension, a field in which Paul Magès was the pioneering engineer at Citroën: having joined the Citroën design office in 1939-1940, he developed the hydropneumatic suspension there, the first plans for which date from 17 February 1944 (Hydropneumatic suspension plans with differential interaction), and continued his career there until his retirement in September 1974 (photographs of retirement). The term "hydrostatic transmission" refers, in automotive history, to research aimed at transmitting engine power hydraulically rather than mechanically — an avenue explored by several manufacturers at that time to simplify or automate the gearbox.

These elements of general context are, however, not confirmed by the document itself, which mentions neither the Citroën brand, nor Paul Magès, nor a precise date.

Archivist's perspective

This plan appears to be a technical study piece intended for design office departments, rather than a communication document: the absence of explanatory legends and the density of the cross-sectional views suggest internal use p. 1.

The reference "P.7245" and the mention "NE 202 / 3 000" probably constitute plan and print identifiers specific to the company's filing system, but their exact meaning remains unspecified in the document.

In the absence of a legible date, this plan could usefully be compared with other archives concerning hydrostatic transmission research or the GS, if such items exist in the collection, in order to clarify its chronology and purpose.