automatic electronic sensors for detecting air losses in tires and for inflating tires; motor protectors, namely, sensors for detecting excessive engine temperature, sensors for detecting low oil pressure, devices and circuits for signaling excessive engine temperature and loss of oil pressure, devices for automatically turning the engine off under one of said sensed conditions; liquid flow rate controls and liquid flow rate meters; controls and sensors for the use in security systems, namely, antitheft detectors and alarm systems, in particular radiofrequency-operated alarm systems; audio-frequency, laser and ultrasound sensors; thermostats; timer for use with - motor protectors, automatic sensors for detecting air losses in tires and for inflating tires and for antitheft alarm systems and detectors; high and low voltage sensors; vehicle speed controls and meters; receivers of signals emitted by sensors of several types, including temperature, pressure, movement, fluid flow, voltage, level, light and sound