Interrelated power delivery controls – including engine control – Transmission control – Engine controlled by transmission
Patent
1999-03-25
2000-12-05
Ta, Khoi Q.
Interrelated power delivery controls, including engine control
Transmission control
Engine controlled by transmission
477110, 12333911, F02D 4114
Patent
active
061559555
DESCRIPTION:
BRIEF SUMMARY
The invention concerns a method for operating a driving unit for motor vehicles, specially tracked vehicles, having a prime mover with torque controllable preferably by an electronic control unit, a load transmitter, a driving transmission and at least one other consuming device.
BACKGROUND OF THE INVENTION
Systems for automatic control of a prime mover torque in certain states of operation of vehicles are basically known.
In many vehicles having stepped automatic transmission, a so-called "motor gearing" is used during traction upshifts in order to compensate for the acceleration excess resulting from the rotary mass being decelerated during the gearshift operation. A desired effect is also the reduction of friction in shifting clutches involved.
Also known are different systems for preventing clutch overloads during gearshifts. It is usual, for example, in vehicles with automatic transmissions that, during the gear change from "N" to a driving step "D" or "R", motor power, motor torque or the motor speed are limited.
These systems have in common that the prime mover torque becomes reduced for a brief time during certain shifting operations.
There have further become known methods for operating a driving unit in which the prime mover power is limited in accordance with certain transmission ratios. Such a driving device has been described, for example, in DE OS 3735246. In this known driving device the motor capacity is limited briefly in a reverse gear in order that the transmission does not have to be (over) dimensioned for this load situation. The limitation of the motor capacity is here firmly linked to the condition that a certain gear (reverse gear) be engaged.
Electronic idling speed controls are likewise related to the instant invention. But in such systems it is essential that the systems be tailored to the idling range (load position "0"). Control is here based on a preset idling speed. A consuming device to be engaged as a rule leads to a speed drop until a control reacts to this.
In many manufactured driving units with a transmission having variable (stepped or continuous) ratios for adaptation to different vehicle speeds, additional consuming devices are directly or indirectly driven by the prime mover. The torque flow to such added consuming devices often is not constant and its magnitude can change depending on the shifting or operating state.
First of all, when the torque flow to the added consuming device can assume relatively high values, the driving performance (speed and acceleration) becomes impaired. Specially in tracked vehicles, a steering transmission, when cornering, can be an added consuming device using substantial portions of the prime mover torque so that the effect on the driving performance is considerable. An cross-drive steering transmission with integrated transmission and steering transmission parts is the object of DE 38 33 784.
SUMMARY OF THE INVENTION
The problem on which the invention is based is to reduce the effects of the variable torque absorption, by added consumer devices, upon the driving performance of the vehicle.
This problem is solved by a method according to the present invention.
The compensation of the torque flow to the added consuming device by an increased prime mover torque prevents, according to the degree of compensation, a lowering of the driving performance (for ex., deceleration) of the vehicle without the driver having to increase the load position. If the "Specific load position" above which the compensation acts is the zero load position, the automatic compensation works in the whole load range.
The method can be used advantageously particularly where there are consuming devices whose absorption torque is not determined exclusively by the prime mover speed. Together with the transmission, at least one other consuming device is included in the method. The method and the developments can also be applied in the presence of several consuming devices.
The use of an electronic control unit for the prime mover offers the advantage that the pr
REFERENCES:
patent: 4724810 (1988-02-01), Poirier et al.
patent: 5000277 (1991-03-01), Hall, III et al.
patent: 5072711 (1991-12-01), Katayama et al.
patent: 5245966 (1993-09-01), Zhang et al.
patent: 5457633 (1995-10-01), Palmer et al.
patent: 5484351 (1996-01-01), Zhang et al.
patent: 5558178 (1996-09-01), Hess et al.
patent: 5577474 (1996-11-01), Livshiz et al.
patent: 5666917 (1997-09-01), Fraser et al.
patent: 5679085 (1997-10-01), Fredriksen et al.
patent: 5692472 (1997-12-01), Bederna et al.
patent: 5866809 (1999-02-01), Soderman
patent: 5947084 (1999-09-01), Russell et al.
Esders, Hans, Hans-Heinrich Harms, Claus Hollander: "Tendenzen der Hydraulik in Baumaschinen--Neuigkeiten zur Bauma '92", O+P Olhydraulik und Pneumatik 36, 1992, Nr. 8, S.490-497; Bild 3 mit Beschreibung.
Boss Ralf
Sorg Johannes
Ta Khoi Q.
ZF Friedrichshafen AG
LandOfFree
Operating method for a motor vehicle driving unit does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Operating method for a motor vehicle driving unit, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Operating method for a motor vehicle driving unit will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-956465