Control for a motor vehicle drive having an automatic transmission

US5335568A · kind A · utility

Assignee

• Siemens Aktiengesellschaft · DE

Inventors

• August Kammerl · Altentreptow, DE
• Friedrich Graf · Eggenfelden, DE

Key dates

• Filing date: Aug 28, 1992
• Grant date: Aug 9, 1994
• Expiry date: Aug 28, 2012

Classification

• Technology area (CPC F): Mechanical Engineering; Lighting; Heating
• CPC primary: F16H2059/087
• WIPO field: Transport
• WIPO sector: Mechanical engineering

Abstract

A motor vehicle drive has an engine and an automatic transmission. A control for the motor vehicle drive includes an engine control for controlling a variable influencing torque of the engine and a transmission control for controlling shifting events of the transmission and for transmitting an intervention signal initiating a shifting event to the engine control. The transmission control includes a first device for ascertaining a current transmission input torque, a memory for storing torque values being maximally allowable during a shifting event, as a function of engine rpm and shifting type, a second device for comparing the current transmission input torque with the maximum allowable torque value at any given time and ascertaining a proportion by which the engine torque is to be varied during the shifting event, and a pulse former circuit for converting the proportion into a pulse modulated signal to be transmitted to the engine control as a control signal for controlling a variation in the engine torque during the shifting event.