Brake controller and short circuit probe disconnect

Abstract

A control for brakes in trailer vehicles comprising a circuit providing pulsed signals to the brakes. It is preferred that the time or width of each pulse is equal but the frequency of brake pulsing is increased in accord with inertially sensed stress. The frequency of signal is directly related to the movement of a dampened cantilever beam which normally blocks the passage of light to a light sensitive target or monitor but wherein the passage of light increases and is attenuated by the beam as the beam moves, under inertial imbalance, to permit added light to be sensed. In addition, the control circuit, vulnerable to short circuits in the vehicle circuit from control element to brakes, is continuously monitored by a disconnect element which senses the existence of the short circuit and accomplishes a disabling of current through the control circuit at a threshold to avoid injury to the control circuit. An electromagnetic coil surrounding a reed switch accomplishes the circuit disconnect in a manner timed by a capacitance in the reed switch line. The probe disconnect timed pulse acts on an indicator visible, audible or tactile to the user of such controls and this intermittent signal indicates the presence of a short circuit requiring correction before the normal operation of the control system can be restored.