Electricity: motive power systems – Automatic and/or with time-delay means – Movement – position – or limit-of-travel
Patent
1984-10-18
1989-10-03
Ro, Bentsu
Electricity: motive power systems
Automatic and/or with time-delay means
Movement, position, or limit-of-travel
G05D 310
Patent
active
048719544
DESCRIPTION:
BRIEF SUMMARY
This invention relates to an actuating means for a flap in motor vehicles, having an electric motor adjusting the flap between two end positions fixed by limit stops in selectable desired positions corresponding to a regulating command. The flap may, for example, be a throttle valve in the intake system of the internal-combustion engine or an air flap of a heating or air-conditioning unit.
It is known to provide such flaps within the framework of a servo system with a position indicator which reports the position of the flap back to a control device. The position indicator may be contacting or non-contacting. Both are known from DE-OS 31 10 949.
Actuating means of this type are high in cost with respect to components on the basis of the position indicator and with respect to regulating technology on the basis of the servo system.
The invention has the objective of providing an actuating means of the type initially mentioned which is clearly simplified in respect to components as well as to regulating technology.
According to the invention, this objective is achieved by provision of a motor which is a step motor and by provision of a flap which is adjusted to an end position, the regulating command corresponding to an adjustment that exceeds the end position.
Because the actuating means is configured as an open loop, a position indicator and a servo system are no longer required. For adjusting the flap to the desired position, it is only necessary to report to the step motor the required number of steps. However, step motors have the disadvantage that in circumstances involving, for example, an excessive start/stop frequency, interfering impulses or mechanical overloading, steps may be lost. This danger is avoided according to the invention in that, when one end positon is adjusted, a step number is reported to the step motor which is higher than the number required when the step motor works without fault. Thus if steps were lost, this loss will be balanced because, by means of this excess step number, the end position of the flap will be reached independable fashion.
It is possible to provide this excess step number for only one end position of the flap. On the other hand, a more rapid correction of possible position errors is achieved by the fact that in the other end position a corresponding excess step number is provided. If the two end positions are encountered with equal frequency, this results in a correction of possible position errors of the flap that is twice as fast.
By means of a further development of the invention, another problem is to be solved that may be connected with the use of a step motor. It is possible to secure the adjustment of the flap in the rest phases by means of a storage unit. Such a storage unit requires a current supply especially in rest phases of the automobile. This disadvantage can be eliminated by means of the fact that such a storage unit is not operative in the rest phases and the first adjustment of the flap after such a rest phase is carried out in such a way that the motor is first adjusted to this end position and the desired position is adjusted from this end position. It is true that this measure in principle is known from DE-OS 31 07 442 for a heating or air conditioning system for a building. However, this measure is carried out at any change of the adjustment of the flap also during a continuous operational phase. This is completely useless for a motor vehicle since, for example, when the flap is developed as a throttle valve, before each position change, the adjustment of the flap would have to be carried out to idling, or full throttle operation.
This one-time adjustment of the flap at the start of an operational phase can be carried out in different ways. Thus the end position to be adjusted may be indicated as one of the two possible end positions. In contrast, a much faster adjustment may be obtained by, in each case, selecting that end position that is closest to the desired position.
These and other objects, features, and advantages of the present inv
REFERENCES:
patent: 3755727 (1973-08-01), Schifalacqua
patent: 4401928 (1983-08-01), Kamijo et al.
Bayerische Motren Werke A.G.
Ro Bentsu
LandOfFree
Actuating means for a flap in motor vehicles does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Actuating means for a flap in motor vehicles, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Actuating means for a flap in motor vehicles will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-666518