Pressure transducer, e.g. a passenger weight sensor for an automobile airbag unit, comprises a pressure sensitive layer of semiconducting particles distributed within an insulating material layer

摘要

A pressure sensitive transducer comprises a pressure sensitive layer (3a, b) of semiconducting particles (4, 5) distributed within an insulating material layer (6). A pressure sensitive transducer comprises a pressure sensitive layer (3a, b) which is located between the facing conductive layers (2a, b) of two support components (1a, b) and which comprises semiconducting particles (4, 5) distributed within an insulating material layer (6). Current flows between the conductive layers (2a, b) when a compressive force acts on one or both of the support components, the current comprising a first component produced by direct contact of the particles and a larger second component produced by a tunneling conduction phenomenon between the particles. The average spacing between the particles is reduced to <= 100 nm when a shear or compressive force acts on one or both of the support components. When a voltage is applied, the resistance between the conductive layers is reduced as soon as the voltage is increased. Preferred Features: The semiconducting particles comprise spherical and flake carbon particles (4, 5).