Dimensioned drawing of a "Calorstat" hydraulic part — Vedie drawing, ref. E1004-7843

In this document

This technical drawing dated 10.2.71 p. 1 shows a cross-section of a cylindrical mechanical part mounted between two plates, with a helical spring and a central through-rod p. 1.

Main dimensions

Several diameters and lengths are indicated:

An O-ring is specified: Φ=33.7x2.45x38.6, referenced 2D 9 4867 00 U p. 1.

Technical title block

The title block specifies the material: Calorstat 13.309 p. 1, with no indication of treatment, coating or weight provided. The draughtsman is Vedie (no. 3159), the manager is Magès, the date is 10.2.71 p. 1. The designation shown is Calorstat, under the number E1004-7843 p. 1, with the printed mention "Société Anonyme Automobiles Citroën — Reproduction prohibited" p. 1. A handwritten inscription on the edge of the page indicates "H1004-a-001" p. 1.

Context

A Calorstat refers, in the automotive technical vocabulary of the time, to a thermostatic element with expandable wax, used in particular to regulate the opening of a circuit according to temperature. At Citroën, this type of component could be involved in hydraulic or cooling subsystems associated with vehicles equipped with hydropneumatic suspension (DS, then SM, GS).

This general context is not, however, made explicit in the document itself, which is limited to a dimensioned drawing without a functional description of the overall system.

Archivist's perspective

This drawing, precisely dated 10 February 1971, is part of the activities of the Automotive Design Office (B.E.A.), at a time when Paul Magès, who joined Citroën in 1925 and was a self-taught man who became head of the design office (autobiographical notes), signed this definition drawing as manager, still eight years away from his retirement in September 1974 (photographs of retirement). It seems to be a standard part definition task rather than a suspension development per se, the mention "Calorstat" suggesting a heat-sensitive component integrated into a larger assembly, not detailed here.

The presence of the same type of B.E.A. title block and Magès' signature as manager links this document to other drawings in the collection, such as Plan D314-02: clutch control cylinder and piston, which testifies to the same rigorous and dimensioned design method characteristic of the Citroën design office of that era.

The absence of treatment, coating or weight indicated in the title block suggests that this is a preliminary stage or a partial definition drawing of the part.