Citroën technical plates — GS hydrostatic transmission, series E106B (P.7245)

In this document

These two pages bring together Citroën industrial technical plates dedicated to a mechanism of the E106B series, bearing the references P.7245 (repeated three times on page 4) and P.8112 (stamp at the bottom of page 3).

Page 3: detailed nomenclature of a sub-assembly

Page 3 presents a complex cross-section plan, surrounded by a mass of handwritten references connected to the drawing by thin lines: part codes ("E106B-3129", "E106B-3161a", etc.), standardized screws ("Vis HM6-16", "ZD3368200U"), SKF bearings ("SKF.NU.420. φ.150.113.24"), circlips, washers, balls ("bille φ.6", "46 billes φ.4"). Several numerical dimensions appear in the central column (5.443860, 5.454.645, 5.444072…), without it being possible to link them with certainty to a specific part due to the difficulty of reading.

Two title areas name functions of the mechanism: a "[controller] intake" and a "Regulator drive intake for D.R.A." p. 3, which places the assembly within a regulation system. An annotation mentions an "8° inclination" on an oblique rod (p. 3, uncertain), and another mentions an "Engine-gearbox support plane" with the dimension "35.975" p. 3.

The official title block, very damaged, retains the CITROËN logo, the mention "Société Anonyme", the fields "DESSINE / VERIFIE / TRAITEMENT / REVETEMENT / POIDS" (DRAWN / CHECKED / TREATMENT / COATING / WEIGHT), and a number "E1068-3498" p. 3, in addition to the "P.8112" stamp.

Page 4: overall cross-section views

Page 4 is a larger fold-out plan, with several colored (pink, yellow, light blue) and non-colored cross-section views: a longitudinal section showing pinions and shafts, a vertical section with bevel gears, a view with a splined shaft connected to a seal or bellows, a central view with internal rods/pistons, and a view with a large splined disc surrounded by bolts (differential or drive plate). The reference P.7245 appears three times, and a number "N° 207 3000" also appears. A title block at the bottom right contains a barely legible table.

Context

As a benchmark external to the document: the GS series, launched by Citroën in 1970, was the subject of research on hydrostatic transmissions conducted in particular by the engineer Paul Magès, continuing the work begun on the 2 CV and the 3 CV as early as the 1960s. The acronym "D.R.A." mentioned on page 3 could refer to a regulation or automatic reduction unit, but this identification is not confirmed by the document itself.

The number "P.7245" is part of a Citroën project numbering typical of that era, comparable to other references in the collection (P.7994, P.8112).

Archivist's perspective

These plates are typical of design office work: they do not bear Magès' personal mark, but illustrate the translation into standardized industrial plans (nomenclatures of screws, bearings, dimensions) of the research conducted on the hydrostatic transmission. The mention "T.H." visible in the title block of page 3 confirms this belonging to the broader hydrostatic transmission file.

It seems that these two pages document the same mechanical assembly viewed from two complementary angles — the detail of the fastenings and bearings p. 3 and the overall view of the gear trains p. 4 — rather than two distinct mechanisms.

These plates likely find their place in the same file as the Citroën Plan E 3091 — Hydrostatic transmission of vehicle L, 2nd generation, dated from the same year 1974, and complement the Cover page of the folder "Hydrostatic transmission 59-74" which seems to group all these studies together.