Electricity: motive power systems – Periodic – repetitious or successive operations control of...
Patent
1999-07-02
2000-11-21
Masih, Karen
Electricity: motive power systems
Periodic, repetitious or successive operations control of...
318DIG2, 318444, 1525013, 15250C, H02P 104
Patent
active
061507830
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
Prior Art
The invention is based on a windshield wiper device. A device and a process for a regulated windshield wiper device for vehicles is already known (German Patent Disclosure 32 08 121 A1). The control circuit in that instance has a position regulator that sends a control variable to the motor circuit and is supplied on the one hand with the rotational position of the motor drive shaft as a regulation variable and on the other hand, is supplied with a presettable desired course of the wiper movement as a time-dependent guidance variable.
Generally, the regulator influences the regulation variable with the aid of the control variable so that the regulating deviation (guidance variable minus regulation variable) is as small as possible. The regulating deviation in a dynamic, time-dependent regulation, however, cannot be arbitrarily reduced e.g. by increasing the control circuit amplification, since the change of the control variable and the effect on the regulation variable are time-delayed and the consequently inevitable phase shifts in the control circuit would lead to oscillations (U. Tietze, Ch. Schenk, Halbleiterschaltungstechnik [Semi-Conductor Switching Technology] 5.sup.th edition, p. 688 ff).
Frequently, more powerful motors, faster computers, etc. in a control circuit are ruled out due to the cost reduction desired by the vehicle manufacturer. This in turn likewise leads to a greater regulation deviation.
SUMMARY OF THE INVENTION
The device according to the invention and the process according to the invention for a windshield wiper assembly, has the advantage that the regulation deviation is compensated for. A correction variable is determined, which corresponds to the regulation deviation and corrects the guidance variable precisely so that the difference between the uncorrected guidance variable and the regulation variable that follows it becomes approximately zero.
It is particularly advantageous that the correction variable is to be determined from the deviation between only at least two variables, namely from the regulation variable and the guidance variable, and that other parameters, such as the control variable, or variables derived from the above-mentioned variables, can be used to determine the correction variable.
It is furthermore particularly advantageous that the wiping region is divided into two regions. If the wiper leaves one of its two end positions or reversal positions, then in the first region wiped through, a correction variable is determined by means of the measured and stored values of the regulation variable and the control variable. The guidance variable in the subsequent second region is corrected with this correction variable so that the wiper reaches its other provided end position or reversal position by taking into account external influences or interference variables.
It is furthermore advantageous that the system elasticities of the wiper assembly are included in the guidance variable by taking into account the wiper speed and the rigidity of the wiper assembly so that the wiping region is independent of the elasticities and is therefore always identical.
The novel features which are considered as characteristic for the present invention are set forth in particular in the appended claims. The invention itself, however, both as to its construction and its method of operation, together with additional objects and advantages thereof, will be best understood from the following description of specific embodiments when read in connection with the accompanying drawings.
FIG. 1 shows a regulated windshield wiper device for a windshield wiper assembly, FIG. 2 shows a graph of the wiper position as a function of time.
DESCRIPTION OF THE PREFERRED EMBODIMENT
The windshield wiper device 10 has a regulating unit 12 and a motor 14 that is regulated by the regulating unit 12. The electronically reversible motor 14 drives a wiper 16 by way of a linkage, not shown, so that the wiper 16 oscillates back and forth between two end positions 18.1
REFERENCES:
patent: 4544870 (1985-10-01), Kearns et al.
patent: 5860185 (1999-01-01), Ponziani
U. Tietze, Ch. Schenk, Halbleiterschaltungstechnik, 5. Auflage, pp. 689-714 .
May Michael
Michenfelder Gebhard
Masih Karen
Robert & Bosch GmbH
Striker Michael J.
LandOfFree
Device and method for a wiping system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Device and method for a wiping system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Device and method for a wiping system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1260697