System and method for vehicle engine speed control during a garage shift

Patent metadata

Field	Value
Publication number	US-10132255-B2
Application number	US-201715397760-A
Country	US
Kind code	B2
Filing date	Jan 4, 2017
Priority date	Jan 4, 2017
Publication date	Nov 20, 2018
Grant date	Nov 20, 2018

Abstract

A method and system for controlling vehicle engine speed during a garage shift includes determining a K-factor of a torque converter based upon a speed ratio of the torque converter, normalizing the K-factor, and controlling an engine speed based upon the normalized K-factor.

First claim

What is claimed is:

1. A method for controlling vehicle engine speed during a garage shift, the method comprising:
determining a K-factor of a torque converter based upon a determined speed ratio of the torque converter;
controlling an engine speed based upon the determined K-factor; and
normalizing the determined K-factor and wherein the controlling the engine speed is based upon the normalized K-factor, wherein the normalizing the determined K-factor comprises dividing the square of a K factor corresponding to a speed ratio of zero by the square of the determined K-factor corresponding to the determined speed ratio, and wherein the controlling the engine speed comprises:
determining an engine torque compensation based upon the normalized K-factor; and
controlling an engine torque based upon the determined engine torque compensation.

2. A system for controlling an engine speed during a garage shift for a vehicle including an engine, a transmission and a torque converter, the system comprising:
a controller programmed to:
determine a K-factor based upon a speed ratio of the torque converter; and
control an engine speed based upon the determined K-factor; and

an engine speed sensor that measures an engine speed and outputs an engine speed signal indicative of the measured engine speed; and
a turbine speed sensor that measures a turbine speed of the torque converter and outputs a turbine speed signal indicative of the measured turbine speed, and wherein the controller is further programmed to:
determine the speed ratio of the torque converter based upon the engine speed signal and the turbine speed signal and wherein the controller determines the K-factor based upon the determined speed ratio; and
determine a normalized K-factor based upon the determined K-factor and wherein the controller determines an engine torque compensation based upon the normalized K-factor, wherein the controller determines the normalized K-factor based upon the square of a K-factor corresponding to a speed ratio of zero divided by the square of the determined K-factor corresponding to the determined speed ratio.

Assignees

• Gm Global Tech Operations Llc

Inventors

• Yang Koon Chul
• Kou You Seok

Classifications

• F16H63/50

  Signals to an engine or motor · CPC title

• F02D2400/12

  Engine control specially adapted for a transmission comprising a torque converter or for continuously variable transmissions · CPC title

• F02D41/0215 Primary

  in relation with elements of the transmission · CPC title

• F02D2200/101

  Engine speed · CPC title

• F02D41/023 Primary

  in relation with the gear ratio shifting (conjoint control for improving gear change B60W30/19) · CPC title