BEA note by Paul Magès on hydraulic mini-motors (windscreen wiper, fan, electricity), 1960

In this document

This handwritten note from the BEA (Automotive Design Office), signed "Mr Magès" with an internal telephone number (3159), lists three uses for small-displacement hydraulic motors (approximately 1 cm³) p. 1.

I. Windscreen wiper

A 1 cm³ displacement hydraulic motor intended for operating a windscreen wiper ran for 1500 hours. Its power is considered "overabundant", and it can be supplied with a return pressure of 30 kg/cm² p. 1.

II. Fan

Tests were conducted under conditions of 150 kg/cm² at 3600 rpm. Several motors ran for 1000 hours, with one reaching 1650 hours. The note mentions a distribution system deemed "unsatisfactory" and three points that remained pending:

III. Electrical power source

Two tests are reported:

1. A dynamo driven by a variable-displacement motor, allowing for constant voltage within 0.3 volts regardless of consumption needs, for a maximum power of 400 watts p. 1.
2. A fixed-displacement alternator (CGE brand), delivering a power of 300 watts, with tests underway aimed at reducing "internal parasitic forces" p. 1.

The note is dated 8 November 1960 p. 1.

Context

At Citroën, the BEA (Automotive Design Office) refers to the advanced research department where Paul Magès developed the hydropneumatic suspension. It is well known that this hydraulic technology, created for the suspension, subsequently permeated other vehicle functions (power steering, braking) — the exploration of hydraulic mini-motors for accessories such as the windscreen wiper or ventilation is part of this logic of diversifying the uses of pressurized fluid, characteristic of Citroën engineering in the 1950s-1960s.

Archivist's perspective

This short document, with its telegraphic style and sometimes uncertain measurements, likely serves as an internal progress report rather than a formal report: it lists ongoing tests with their raw results, without a definitive conclusion p. 1.

It bears witness to an exploration phase where Magès and his team sought to extend the hydraulic principle to peripheral vehicle accessories, far beyond the suspension alone. The "pending" points regarding the fan p. 1 suggest that this avenue was not yet mature at that date.

This document would benefit from being compared with other BEA notes from the same period dealing with auxiliary hydraulic applications, if they exist in the collection. PMREFnumberEND