Mercury inertial transducer and light-emitting indicator for motor

Abstract

A mercury inertial transducer includes a casing which defines an essentially L-shaped cavity having a substantially horizontal lower arm and a substantially vertical ascending arm; a volume of mercury which, in the rest condition, occupies the lower arm and essentially does not occupy the ascending arm; an input electrode which penetrates the lower arm from the outside and is permanently immersed in the mercury, and a series of separate output electrodes which are spaced along the ascending arm and can be reached in succession by the mercury when it rises in the ascending arm due to an inertial force directed along the lower arm towards the ascending arm. The transducer may be incorporated in a unit including a support which can be fixed to a movable object, such as a motor vehicle, and on which the transducer is mounted so that the inclination of its lower arm to the horizontal and of its ascending arm to the vertical can be adjusted. The transducer may also be incorporated in a deceleration and stopping indicator including an elongate hollow body provided with means for fixing to the bodywork of a motor vehicle and carrying an array of electrical light units spaced along its length. These light units are aligned transverse the vehicle and face rearwardly with respect to the direction of travel. The inertial transducer is mounted in the hollow body and its output electrodes are each connected to at least one of the light units.