Shift control device of automatic transmission

• US 20060190154A1
• Filed: 07/09/2004
• Published: 08/24/2006
• Est. Priority Date: 07/28/2003
• Status: Active Grant

• Current Assignee: Aisin AW Company Limited (Aisin Corp.), Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Original Assignee: Aisin AW Company Limited (Aisin Corp.), Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation)
• Inventors: Tanaka, Yoshikazu, Sato, Yasushi, Watanabe, Kiyoshi, Yoshida, Satoshi, Kondo, Masami, Matsubara, Tooru, Fukatsu, Akira
• Granted Patent: US 7,473,208 B2
• Time in Patent Office: Days
• US Class Current: 701/51
• CPC Class Codes: B60W 10/04 including control of propulsion units
• CPC Class Codes: B60W 10/11 Stepped gearings
• CPC Class Codes: B60W 2510/1015 Input shaft speed, e.g. turbine speed
• CPC Class Codes: B60W 2520/105 Longitudinal acceleration
• CPC Class Codes: B60W 2540/12 Brake pedal position
• CPC Class Codes: B60W 2710/1011 Input shaft speed, e.g. turbine speed
• CPC Class Codes: B60W 30/18 Propelling the vehicle
• CPC Class Codes: B60W 30/1819 Propulsion control with control means using analogue circuits, relays or mechanical links
• CPC Class Codes: F16H 2061/0477 by suppression of excessive engine flare or turbine racing during shift transition engine flare caused by lock-up release F16H61/143
• CPC Class Codes: F16H 2061/0488 during range shift from neutral (N) to drive (D)
• CPC Class Codes: F16H 2312/022 Preparing to drive off
• CPC Class Codes: F16H 35/10 Arrangements or devices for absorbing overload or preventing damage by overload for screw mechanisms F16H25/2021
• CPC Class Codes: F16H 61/0437 by using electrical signals F16H61/0403 and F16H61/061 take precedence
• CPC Class Codes: F16H 61/686 with orbital gears
• CPC Class Codes: F16H 63/502 for smoothing gear shifts

Abstract

A shift control device of an automatic transmission comprising detection means for detecting a shift from a non-drive to a drive position; output means for outputting a command to execute an engine output lowering; detection means for detecting a transmission input revolution number and control means for engaging the friction engagement element by direct pressure control in response to a detection of said transmission input revolution number having been decreased to a predetermined value.

Claims

1. A shift control device of an automatic transmission transmitting power from an engine, said automatic transmission including a friction engagement element that is engaged in a drive position and disengaged in a non-drive position, an engagement pressure of said friction engagement element being controllable by direct pressure, comprising:

detection means for detecting a shift from said non-drive position to said drive position;

output means for outputting a command to execute an output lowering process of said engine to an engine control device in response to detection of the shift to said drive position;

detection means for detecting an input revolution number to said automatic transmission; and

control means for starting engagement of said friction engagement element by direct pressure control in response to detection of said input revolution number having been decreased to a predetermined revolution number by said output lowering process.

2. The shift control device of an automatic transmission according to claim 1, further comprising means for controlling the engagement pressure using the direct pressure control to suppress transmission of the power by said friction engagement element in response to detection of the shift to said drive position.

3. The shift control device of an automatic transmission according to claim 1, wherein said predetermined revolution number is set based on a heat absorption amount of said friction engagement element at the time of engagement.

7. The shift control device of an automatic transmission according to claim 1, wherein said drive position is a forward drive position, said non-drive position is a neutral position, and said friction engagement element is an input clutch.

15. The shift control device of an automatic transmission according to claim 2, wherein said drive position is a forward drive position, said non-drive position is a neutral position, and said friction engagement element is an input clutch.

4. A shift control device of an automatic transmission transmitting power from an engine, said automatic transmission including a friction engagement element that is engaged in a drive position and disengaged in a non-drive position, an engagement pressure of said friction engagement element being controllable by direct pressure, comprising:

detection means for detecting a shift from said non-drive position to said drive position;

output means for outputting a command to execute an output lowering process of said engine to an engine control device in response to detection of the shift to said drive position; and

control means for starting engagement of said friction engagement element (310) by direct pressure control after a lapse of a predetermined period of time following initiation of said output lowering process.

5. The shift control device of an automatic transmission according to claim 4, further comprising means for controlling the engagement pressure using the direct pressure control to suppress transmission of the power by said friction engagement element in response to detection of the shift to said drive position.

6. The shift control device of an automatic transmission according to claim 4, wherein said predetermined period of time is set based on a time when a revolution number to said automatic transmission becomes a revolution number that is set in accordance with a heat absorption amount of said friction engagement element at the time of engagement.

16. The shift control device of an automatic transmission according to claim 5, wherein said drive position is a forward drive position, said non-drive position is a neutral position, and said friction engagement element is an input clutch.

17. The shift control device of an automatic transmission according to claim 6, wherein said drive position is a forward drive position, said non-drive position is a neutral position, and said friction engagement element is an input clutch.

8. A shift control device of an automatic transmission transmitting power from an engine, said automatic transmission including a friction engagement element that is engaged in a drive position and disengaged in a non-drive position, an engagement pressure of said friction engagement element being controllable by direct pressure, comprising:

a detection unit detecting a shift from said non-drive position to said drive position;

an output unit outputting a command to execute an output lowering process of said engine to an engine control device in response to detection of the shift to said drive position;

a detection unit detecting an input revolution number to said automatic transmission; and

a control circuit starting engagement of said friction engagement element by direct pressure control in response to detection of said input revolution number having been decreased to a predetermined revolution number by said output lowering process.

9. The shift control device of an automatic transmission according to claim 8, further comprising a circuit controlling the engagement pressure using the direct pressure control to suppress transmission of the power by said friction engagement element in response to detection of the shift to said drive position.

10. The shift control device of an automatic transmission according to claim 8, wherein said predetermined revolution number is set based on a heat absorption amount of said friction engagement element at the time of engagement.

14. The shift control device of an automatic transmission according to claim 8, wherein said drive position is a forward drive position, said non-drive position is a neutral position, and said friction engagement element is an input clutch.

18. The shift control device of an automatic transmission according to claim 9, wherein said drive position is a forward drive position, said non-drive position is a neutral position, and said friction engagement element is an input clutch.

19. The shift control device of an automatic transmission according to claim 10, wherein said drive position is a forward drive position, said non-drive position is a neutral position, and said friction engagement element is an input clutch.

11. A shift control device of an automatic transmission transmitting power from an engine, said automatic transmission including a friction engagement element that is engaged in a drive position and disengaged in a non-drive position, an engagement pressure of said friction engagement element being controllable by direct pressure, comprising:

a detection unit detecting a shift from said non-drive position to said drive position;

an output unit outputting a command to execute an output lowering process of said engine to an engine control device in response to detection of the shift to said drive position; and

a control circuit starting engagement of said friction engagement element by direct pressure control after a lapse of a predetermined period of time following initiation of said output lowering process.

12. The shift control device of an automatic transmission according to claim 11, further comprising a circuit controlling the engagement pressure using the direct pressure control to suppress transmission of the power by said friction engagement element in response to detection of the shift to said drive position.

13. The shift control device of an automatic transmission according to claim 11, wherein said predetermined period of time is set based on a time when a revolution number to said automatic transmission becomes a revolution number that is set in accordance with a heat absorption amount of said friction engagement element at the time of engagement.

20. The shift control device of an automatic transmission according to claim 13, wherein said drive position is a forward drive position, said non-drive position is a neutral position, and said friction engagement element is an input clutch.