System for suggesting a change of gear for a motor vehicle provided with an engine and a gear change with discrete ratios

摘要

The system (10) comprises
first and second detector (12, 13) capable of providing electrical signals indicating the transmission ratio (Ä i ) for the gear engaged by the gear change (5) and the engine (1) rotation speed (n) respectively,
an indicator of the torque (T) provided by the engine (1),
memory devices (14) in which a first and second table or map (M1, M2) respectively are stored and respectively provide corresponding threshold values (T U ; T D ) for the torque (T) delivered by the engine (1) above which and below which respectively the desirability of changing to the immediately higher transmission ratio (Ä i+1 ) and the immediately lower transmission ratio (Ä i-1 ) in relation to the transmission ratio (Ä i ) currently engaged by the gear change (5) and the engine (1) rotation speed (n) should be indicated, and
a processing unit (11) designed to activate a signal generator (15) to indicate the desirability of changing to the higher gear (Ä i+1 ) ratio or lower gear (Ä i-1 ) ratio respectively when the torque (T) delivered by the engine (1) is less than the threshold value (T U ) provided by the first table or map (M1) and when the torque (T) provided by the engine (1) is higher than the threshold value (T D ) provided by the second table or map (M2) respectively.