Selected for their robustness, speed of execution, ease of installation and maintenance, and low cost, pneumatic actuators and directional control valves (see
[BM 6 111]
) play a major role in sequential and combinatorial automation (see
[BM 6 112]
) in the manufacturing industry.
The ever-increasing performance requirements, the advanced development of digital and power electronics, and the elaboration of robust control laws have led, over the last decade, to the development of continuously controlled electropneumatic systems, known as "proportional pneumatic technology", and, in particular, to the development and marketing of electropneumatic power modulators.
This article is written against this background, presenting these new "proportional" components in terms of their principle, construction technology and functional characteristics. By way of example, we look at two industrial applications, briefly describing electropneumatic systems in their entirety. This dossier is deliberately limited to electropneumatic power modulators and two typical applications, and does not cover the methodologies for developing and processing control laws, which can be found in the works cited in the bibliography.