Powertrain control device

• US 6,014,604 A
• Filed: 10/13/1998
• Issued: 01/11/2000
• Est. Priority Date: 10/26/1994
• Status: Expired due to Fees

• Current Assignee: HITACHI, LTD. & HITACHI CAR ENGINEERING CO., LTD.
• Original Assignee: HITACHI, LTD. & HITACHI CAR ENGINEERING CO., LTD.
• Inventors: Sato, Kazuhiko, Ibamoto, Masahiko, Kuroiwa, Hiroshi, Shida, Masami, Okada, Mitsuyoshi
• Primary Examiner(s): Cuchlinski, Jr., William A.
• Assistant Examiner(s): PIPALA, EDWARD J
• Application Number:
  US09/170,192
• Time in Patent Office: 455 Days
• Field of Search: 701/53, 701/54, 701/55, 701/56, 701/58, 701/60, 701/64, 701/66, 477/107, 477/109, 477/110, 477/115, 477/129, 477/156
• US Class Current: 701/54
• CPC Class Codes: B60W 10/04 including control of propulsion units
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/11 Stepped gearings
• CPC Class Codes: B60W 2050/0031 Mathematical model of the vehicle
• CPC Class Codes: B60W 2710/0666 Engine torque
• CPC Class Codes: B60W 30/1819 Propulsion control with control means using analogue circuits, relays or mechanical links
• CPC Class Codes: B60W 30/19 Improvement of gear change, e.g. by synchronisation or smoothing gear shift
• CPC Class Codes: F16H 61/0021 Generation or control of line pressure
• CPC Class Codes: F16H 63/502 for smoothing gear shifts
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

The object of this invention is to reduce shift shocks by controlling the driving torque during gear shift changing so that the driving torque is represented by a smooth, ideal waveform.

The driving torque calculating means estimates the output shaft torque of the automatic transmission from the engine torque characteristic or torque converter characteristic and, based on the estimated driving torque, generate a targeted torque pattern during gear shift changing. The engine torque control value calculating means calculates the control value for controlling the engine output torque, i.e., an ignition timing correction value Δθig, so as to eliminate the deviation between the targeted torque and the driving torque estimated by the driving torque calculating means. This ignition timing correction approximates the driving torque to the smooth targeted torque. This configuration realizes the object mentioned above.

Claims

1. A powertrain control device for a vehicle having an engine, an automatic transmission, a torque converter, a transmission change signal generator for generating a transmission change signal at a transmission change timing, and a line pressure control device for controlling a line pressure of the automatic transmission, comprising:

at least one microcomputer to control the engine and the automatic transmission, wherein the powertrain control device has functions as follows;

(a) calculating a present output shaft torque of the automatic transmission;

(b) calculating a target torque based on the calculated present output shaft torque at a predetermined time after generating the transmission change signal;

(c) calculating an ignition timing correcting value by using a specified conversion coefficient and a deviation between the calculated present output shaft torque and the calculated target torque;

(d) outputting an engine control signal for controlling the engine based on the calculated ignition timing correcting value.

2. A powertrain control device for a vehicle having an engine, an automatic transmission, a torque converter, a transmission change signal generator for generating a transmission change signal at a transmission change timing, and a line pressure control device for controlling a line pressure of the automatic transmission, comprising:

at least one microcomputer to control the engine and the automatic transmission, wherein the powertrain control device has functions as follows;

(a) calculating a turbine torque of the automatic transmission at predetermined time intervals irrespective of the transmission change signal;

(b) calculating a first line pressure value at a predetermined time interval of the transmission change signal for controlling the line pressure approaching the first line pressure value based on the calculated turbine torque;

(c) outputting a first line pressure control signal to the line pressure control device;

(d) calculating a second line pressure value at a predetermined time interval of the transmission change signal for controlling the line pressure approaching the second line pressure value based on the calculated turbine torque;

(e) outputting a second line pressure control signal to the line pressure control device;

(f) outputting a third line pressure control signal for controlling the line pressure being returned to the static line pressure after the transmission change timing to the line pressure control device.