Method for adaptation of pressure of an overlapping upshifting

Details Method for adaptation of pressure of an overlapping upshifting Method for adaptation of pressure of an overlapping upshifting

2000-03-13

2001-07-17

Estremsky, Sherry (Department: 3681)

Interrelated power delivery controls, including engine control

Transmission control

Transmission controlled by engine

C477S110000, C477S154000

Reexamination Certificate

active

06261204

ABSTRACT:

BACKGROUND OF THE INVENTION
The invention relates to a method for adaptation of pressure of an overlapping upshift in an automatic transmission having a first opening and a second closing clutch. The overlapping shift comprises two phases. During the first phase, banking the transmission input rotational speed is adjusted by regulating the pressure level of the first clutch. During the second phase, the second clutch takes over the load from the first clutch.
In electrohydraulically controlled automatic transmission, the gear shifts can be carried out as overlapping gear shifts. The applicant's application DE-OS 42 40 621 thus proposes a control and regulation method for an overlapping gear shift. The overlapping gear shift consists here of a first phase during which banking the transmission input rotational speed is adjusted and a second phase during which the actual take-over of the load takes place. Rotational speed banking means that, via the pressure level of the first clutch, a increased transmission input rotational speed is adjusted such as would result from the reduction ratio at the start of the upshift. The load take over, i.e. the moment at which the second clutch begins to take over the load from the first clutch, is when the banking of rotational speed again decreases. The above described method has recommended itself in the practice. However, some drivers find the length of time of the first phase is too long, i.e. the banking adjustment of the transmission input rotational speed takes too long.
SUMMARY OF THE INVENTION
Departing from the above described prior art, the problem on which the invention is based is to increase the spontaneity of the automatic transmission.
A first solution of the problem consists in measuring the time elapsed from issuance of the shift command until the transmission input rotational speed has reached the banked rotational speed. This is then compared with a predetermined time while calculating a difference value and totaling in a summation memory the difference value to which a sign is given. If the value of the summation memory exceeds a limit value, an adaptation value is stored in a correction memory so that the disconnection pressure level of the first clutch, i.e. the opening thereof, is adjusted in subsequent gear shifts.
A second solution of the problem consists in the presence of the adjustment criteria realized in the first solution, of adjusting the disconnection moment of the first clutch, i.e. the opening moment thereof, is adjusted in subsequent gear shifts.
In development of the first and also of the second solution, it is proposed that both the summation memory and the correction memory be divided into transmission input torque, temperature and rotational speed classes. For the rotational speed classes can be used both the transmission input and the transmission output rotational speeds. The inventive solution and the development thereof offer the advantage that the transmission input rotational speed be adjusted to the banking value more quickly, since here the adapted value is used as command variable of the closed loop control. A shorter regulation phase results herefrom. The reaction of the automatic transmission is thus more closely linked to the driver's behavior, thereby acting more spontaneously.
Other advantageous developments are contained in the subclaims wherein, according to claim
7
, the gear shift for the adjustment is not evaluated when prior to start of the second phase, one of the following conditions is present: throttle valve value less than a limit value, or gradient of the throttle valve more than a limit value, or coasting operation is detected, or shift command is detected via selector lever, or the temperature of the ATF (automatic transmission fluid) is below a limit value.


REFERENCES:
patent: 4928235 (1990-05-01), Mehta et al.
patent: 5319963 (1994-06-01), Benford
patent: 5609068 (1997-03-01), Gruhle et al.
patent: 5795262 (1998-08-01), Robinson
patent: 5911648 (1999-06-01), Dreibholz et al.
patent: 39 22 051 C2 (1991-01-01), None
patent: 39 28 814 A1 (1991-03-01), None
patent: 42 40 621 A1 (1994-06-01), None
patent: 195 44 940 A1 (1995-01-01), None
patent: 196 03 617 A1 (1996-01-01), None
patent: 196 12 893 A1 (1996-10-01), None
patent: 195 11 897 A1 (1996-10-01), None
patent: 196 12 928 A1 (1996-10-01), None
patent: 195 31 675 A1 (1997-03-01), None
patent: 195 45 588 (1997-06-01), None
patent: 0482 691 (1992-04-01), None
patent: 07 50 139 A2 (1996-12-01), None
patent: 07 83 079 A1 (1997-07-01), None
patent: 96/01961 A1 (1996-01-01), None
patent: 96/17189 A1 (1996-06-01), None

Affiliated with

Also associated with

Rating

Method for adaptation of pressure of an overlapping upshifting does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Method for adaptation of pressure of an overlapping upshifting, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method for adaptation of pressure of an overlapping upshifting will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2479422