Method of and apparatus for braking a tractor-trailer combination

摘要

A method of controlling the braking of a tractor-trailer combination (10) in which the tractor (11) includes a drive train having an engine and at least one ground-engaging member (14, 16) driveably connected thereto via an adjustable-ratio transmission; at least one ground-engaging member (14, 16) of the tractor includes at least one tractor brake; and at least one ground-engaging member (17) of the trailer (12) includes at least one further, trailer brake, comprises the steps of determining (i) the deceleration of the tractor-trailer combination (10) resulting from braking effort applied via the tractor brake and/or (ii) the deceleration of the tractor-trailer combination resulting from engine braking. The method also includes establishing from one or both the said, determined decelerations as a target value in a control system a braking effort of the trailer brake that approximates the braking of the tractor-trailer combination (10) to the braking of the tractor (11) when considered alone.

主权项

1. A method of controlling the braking of a tractor-trailer combination in which the tractor includes a drive train having an engine and at least one ground-engaging member driveably connected thereto via an adjustable-ratio transmission; at least one ground-engaging member of the tractor includes at least one tractor brake; and at least one ground-engaging member of the trailer includes at least one further, trailer brake, the method comprising:
determining a reference deceleration value AX—REF derived from (i) the deceleration of the tractor, when considered alone, resulting from braking effort applied via the tractor brake and/or (ii) the deceleration of the tractor, when considered alone, resulting from engine braking; measuring a value AX—MEASURED of the deceleration of the tractor-trailer combination; and comparing in a closed-loop control arrangement the reference and measured deceleration values and establishing therefrom a target value of braking effort of the trailer brake that approximates the braking of the tractor-trailer combination to the braking of the tractor when considered alone, wherein the reference deceleration value is calculated in accordance with the expressionAX_REF=FTRACTOR_BRAKESMTRACTOR wherein AX—REF is the reference deceleration value, FTRACTOR—BRAKES is the brake force generated by the tractor from the braking effort applied via the at least one tractor brake and/or by engine braking and MTRACTOR is the mass of the tractor omitting the mass of the trailer, wherein the target value of braking effort of the trailer brake is FTRAILER—BRAKES—CLOSED—LOOP and is related to the reference deceleration value AX—REF by the expression:AX_REF≅⁢FENGINE_BRAKES+FTRAILER_BRAKES⁢_CLOSED⁢_LOOPMTRACTOR+MTRAILER=AX_MEASUREDin which additionally AX—MEASURED is a measured value of deceleration of the tractor-trailer combination, FENGINE—BRAKE is the braking effort resulting from engine braking and MTRAILER is the mass of the trailer forming part of the combination.