Method and apparatus for braking rail-guided vehicles automatically and accurately with respect to a deceleration distance

Abstract

The method uses a computer which, in accordance with a function based on either time or distance of deceleration, delivers speed values to a control apparatus for the braking force of the vehicle. The control apparatus is utilized to deliver correcting control signals for correcting the braking forces, and a fixed braking force control signal is provided and has a magnitude which is rated for a braking which is accurate as to the deceleration distance under conditions of an ideal track and an average train length, as when the rail-guided vehicles are locomotive-drawn railroad trains. The correcting control signals are combined, after a first time delay and in the correct mathematical polarity, or relationship, to the fixed braking force control signal. Upon actuation of the vehicle brake, only the fixed braking force control signal is applied and the computer is actuated for picking up and storing the actual speed at this instant. It is only after the expiration of a first delay time that the computer proceeds to compute the reference speed or correcting speed values while starting from the stored actual speed as the initial reference value, and the control apparatus is enabled only after a second delay time has expired. As the actual speed approaches the desired speed, following deceleration, the fixed braking force control signal is switched off at a differential period of time in advance and the connections are changed from the reference speed values of the computer to the desired speed as a new reference value. The apparatus includes a differential amplifier to which are applied the desired speed value and the actual speed value and which controls a limit-value stage switch, upon exceeding a threshold value, actuates the computer and brings a first switching element, following the computer, and a second switching element, into closed positions. The first switching element is connected to one input and the desired speed is applied to the other input of a maximum evaluator whose output is connected to a braking force controller which is controlled by the evaluator output and by the actual speed and which is further actuable, with delay, by the computer. The braking force controller delivers braking force control signals to a summing point to which a fixed basic braking force control signal is applied through the second switching element.

Dependencies are inferred from the claim text.