Fluid-based acceleration and tilt sensor

Claim 1

Sensor (10) for detection of at least one of acceleration and tilt of a movable object, having a sensor housing (11) having opposing sidewalls defining an interior space (12); a fluid (15) partially filling said interior space (12); a bubble structure (16, 18) of ceramic material including a membrane formed by thick-film technology formed on each of said sidewalls in said interior space; at least two electrically heatable, temperature-sensitive electrical circuit elements forming part of an evaluation circuit; wherein said two temperature-sensitive electrical circuit elements are spaced apart, in said interior space (12) of the sensor; said temperature-sensitive elements are film resistance elements, formed on respective ceramic bubble structures (16, 18), whose resistances change as a function of degree of fluid coverage and resulting heat dissipation; said two elements are arranged such that, in a rest position of the sensor (10), they are equally wetted by said fluid (15), while when acceleration and tilt do not cancel each other out, such acceleration and tilt lead to a differing degree of wetting of said two elements by said fluid (15), and thus to a differing degree of heat dissipation, resulting in a resistance difference which is evaluated by said evaluation circuit.