US 5,582,558 A · Combined system for assisting shifting of manual transmission

Abstract

A vehicle drive incorporates a speed control that assists an operator in shifting the transmission without requiring the clutch, or synchronization of engine speed. An operator is provided with a single switch that allows a prediction of the next shift direction, and also a request for torque elimination to begin a gear shift. The electronic control unit modifies the engine fueling to a predicted value to achieve a zero torque load, thus allowing the operator to move the transmission to neutral. The transmission is provided with a neutral switch that provides a positive signal to the electronic control unit of when the transmission is in neutral and when it is engaged. Once the electronic control receives the neutral signal, it begins to modify the engine speed to achieve the desired synchronization speed. The operator is thus able to engage the new gear. Once the new gear is engaged, control over the engine returns to the operator.

Claims34

Dependent claims

A vehicle drive system comprising:

(a) an engine having an output shaft and an electronic control unit for controlling said engine;
(b) a multi-speed transmission operably connected to be driven by said engine output shaft;
(c) a manual stick shift to allow an operator to change the speed ratio of said transmission;
and
(d) a driver switch allowing an operator to send a shift intent signal to said electronic control unit of whether an upshift or a downshift is to be expected as the next shift, and further to allow an operator to request torque elimination on the connection between the transmission and the engine, said driver shift intent signal and said torque elimination request passing through a single input to said electronic control unit, and there being individual resistances associated with each switch state such that an analog signal received from said single input at said electronic control unit is associated with a particular combination of switch signals, said electronic control unit comparing said analog signal to expected signals in a table to identify the combination of signals being sent by said operator, said electronic control unit indicating a fault should said actual analog signal not fall within one of several ranges for said expected signals.

2 more elements

A method of controlling the operation of a vehicle comprising the steps of:

(a) providing an engine having an output shaft, an electronic control unit for controlling the speed of said engine output shaft, said engine output shaft being connected to drive a multi-speed transmission through a clutch, and said electronic control unit being provided with information regarding a currently engaged gear in said transmission, and further to calculate the speed ratio at a next expected gear and determine a synchronization speed for the engine based upon the speed ratio at said next expected gear and the transmission output speed;
(b) operating a vehicle using the system provided in step (a);
(c) determining the currently engaged gear and whether an upshift or a downshift is to be expected as the next shift based upon system operating conditions;
(d) determining a next expected gear based upon said currently engaged gear and said expected shift of step (c);
(e) receiving a signal that said transmission has been moved to neutral and identifying an engine synchronization speed by multiplying the speed ratio at said next expected gear with the current transmission output speed and beginning to control said output speed of said engine output shaft to approach said synchronization speed;
(f) varying said engine output speed above and below said synchronization speed such that said engine output speed periodically crosses an actual required synchronization speed for said transmission;
and
(g) manually shifting said multi-speed transmission towards said next expected gear.

5 more elements

A method of controlling the operation of a vehicle comprising the steps of:

(a) providing an engine having an output shaft, an electronic control unit for controlling the speed of said engine output shaft, said engine output shaft being connected to drive a multi-speed transmission through a clutch, and said electronic control unit being provided with information regarding a currently engaged gear in said transmission, and further to calculate the speed ratio at a next expected gear and determine a synchronization speed for the engine based upon the speed ratio at said next expected gear and the transmission output speed, said electronic control unit being able to identify an engine parameter that reduces the torque load on the connection between said engine and said transmission, said electronic control unit actuation also controlling of an engine speed retardation feature;
(b) operating a vehicle using the system provided in step (a);
(c) determining the currently engaged gear and whether an upshift or a downshift is to be expected as the next shift based upon system operating conditions;
(d) driving said engine to said engine parameter which reduces torque load upon receipt of an operator indication that a gear shift is being initiated;
(e) determining a desired engine synchronization speed at a next-expected gear by determining said next expected gear based upon said currently engaged gear and said expected shift of step (c);
(f) receiving a signal that said transmission has been moved to neutral and identifying an engine synchronization speed by multiplying the speed ratio at said next expected gear with the current transmission output speed and beginning to control said output speed of said engine output shaft to approach said synchronization speed;
(g) driving said engine output speed to approach said synchronization speed;
(h) actuating said engine speed retardation feature if an upshift is indicated;
and
(i) manually shifting said multi-speed transmission towards said next expected gear.

7 more elements

A method of controlling the operation of a vehicle comprising the steps of:

(a) providing an engine having an output shaft, an electronic control unit for controlling the speed of said engine output shaft, said engine output shaft being connected to drive a multi-speed transmission through a clutch, and said electronic control unit being provided with information regarding a currently engaged gear in said transmission, and further to calculate the speed ratio at a next expected gear and determine a synchronization speed for the engine based upon the speed ratio at said next expected gear and the transmission output speed, and a driver shift intent signal to allow a driver to provide an indication of the next expected shift direction;
(b) operating a vehicle using the system provided in step (a);
(c) determining the currently engaged gear, and the predicted shift direction based upon said driver shift intent switch;
(d) determining a next expected gear based upon said currently engaged gear and said expected shift of step (c);
(e) receiving a signal that said transmission has been moved to neutral and identifying an engine synchronization speed by multiplying the speed ratio at said next expected gear with the current transmission output speed and beginning to control said output speed of said engine output shaft to approach said synchronization speed;
(f) receiving a change in the driver shift intent from said operator switch, after step (e), and recalculating said next expected gear based upon said change driver shift intent, and determining a new synchronization speed based upon said changed driver shift intent;
(g) moving said engine output speed to approach said synchronization speed;
and
(h) manually shifting said multi-speed transmission towards said next expected gear.

6 more elements

Dependencies are inferred from the claim text.

Combined system for assisting shifting of manual transmission

Life of this patent

Combined system for assisting shifting of manual transmission

Life of this patent

Abstract

Claims34