DE19618484A1 - Actuator with pinch protection for moving parts - Google Patents

Abstract

The invention concerns a variable drive with protection against jamming for movable parts, such as in particular windows and sliding roofs in motor vehicles. According to the invention, the number of revolutions or speed of the drive is reduced in given adjusting ranges (x2-x1) in order to satisfy a predetermined spring rate for reducing the kinematic energy. Within the predetermined range, before the "closed" position (x0) is reached, the number of revolutions (n) and/or the power (P) of the drive is/are reduced in linear manner. The reduction to a minimum number of revolutions (nmin) and/or minimum power (Pmin) is effected within a given position range (10). The minimum number of revolutions and/or minimum power is/are reached at a given position (x3) before the "closed" position (x0) and is/are substantially constant. In accordance with the different supply power (Pmax, P2, P1), a linear reduction, for example, is effected along straight lines (12, 13, 14) of different inclination, the position range in which the reduction occurs being of constant length.

Description

State of the art

The invention is based on an adjustment drive Pinch protection for moving parts, such as in particular Windows and sunroofs in motor vehicles, which in Preamble of claim 1 defined genus.

In an adjustment drive known from DE 37 36 400 A1 This type is used to meet a given spring rate in certain adjustment ranges to reduce the kinematic energy a speed or The speed of the drive was reduced. The moving part is driven by a drive motor endangered clamping area, in the foreign body between the movable part and a stationary part can be clamped, moved into a closed position. Because of inevitable Delay in signal processing and inertia of the mechanically moving part, despite one of the Safety device of the anti-trap device Foreign body between the moving part and the stationary part be pinched. To avoid this is with this known actuator provided that the  Adjustment speed when closing the moving part is reduced in the endangered clamping area. Of the The actual pinch protection can then possibly Stop the moving part immediately and possibly the Reverse direction of movement.

In this known adjustment drive, the reduction takes place the speed in steps, d. H. it is of a high Level to a low level in one step Closing speed switched. This allows this abrupt downshifting of the pinch protection wrongly address and on the other hand it will the closing time is extended.

Advantages of the invention

The adjustment drive according to the invention with pinch protection has the characterizing features of claim 1 in contrast, the advantage of the continuous transition from a high to a certain low Closing speed with optimized closing time. On incorrect addressing of the anti-trap protection is included Avoided security.

According to the invention, this is principally achieved by that within the given range before reaching the "Closed" position the speed and / or the power of the drive according to a predetermined functional Context is lowered that the reduction to a Minimum speed or minimum power within one certain position range that this Minimum speed or minimum power at a certain Position before the "closed" position is reached, and that the minimum speed or minimum power essentially is constant. Lowering the speed and / or the  Power of the drive can be chosen according to any functional context are specified. Let it through realizing smooth transitions.

By those laid down in the further claims Measures are advantageous training and Improvements to the arrangement specified in claim 1 possible. In an advantageous embodiment of the adjustment drive according to the invention takes place Linear speed reduction. The effort for that Base point determination is low.

Another embodiment of the invention is a Lowering after an exponential function. Thereby can abrupt speed and / or performance changes be avoided.

According to a particularly advantageous embodiment the invention is carried out according to a predetermined functional relationship to the minimum speed or Minimum power over a constant position range, the rate of lowering depending on the current supply, in particular the Supply voltage changes.

According to a particularly advantageous further alternative embodiment of the invention Reduction to the minimum speed or minimum output via a variable position range, which is Starting point depending on the current one Supply power, in particular the supply voltage, changes.

In a particularly expedient embodiment of the invention the necessary minimum speed or minimum power  determined empirically in such a way that under all conditions, such as especially temperature and humidity, still sufficient high clamping forces are guaranteed.

In an advantageous embodiment of the invention, the Control of the speed or the power of the preferably electrical drive through semiconductor components, in particular linear regulators or clock regulators with variable Pulse-pause ratio.

In a particularly expedient development of the invention provided that the adjustment drive together with a Circuit for protection against jamming of foreign bodies between moving part and fixed stop in the "Closed" position can be used.

According to an advantageous embodiment of this Further development of the invention is in the calculation of Reduction in speed by pinching the each known slope of the reduction according to a predetermined functional relationship between speed and / or power of the Drive can be considered as a correction factor.

In a particularly expedient embodiment thereof Correction provided an adaptive memory in which the controlled reduction of speed and / or power as minor binding is stored.

According to a further advantageous embodiment of the Adjustment drive according to the invention is to improve the Evaluation of the anti-trap protection resolution Path detection increased by using an EXOR link between two Hall sensors and / or by using one multi-polarized magnetic rings.  

A further advantageous embodiment of the invention provides before that the speed and / or power when reaching a very small clear width, e.g. B. <4 mm, again maximum value can be increased to maximum To achieve closing force, especially in the range of Rubber seals.

drawing

The invention is based on several in the drawing illustrated embodiments in the following Description explained in more detail. Show it:

Fig. 1 schematically shows a diagram of a first embodiment of the adjustment drive according to the invention with anti-trap protection, in which a linear speed reduction takes place over a constant position range with different changes in speed, and

Fig. 2 schematically shows a diagram of a second embodiment of the adjustment drive according to the invention with anti-trap protection, in which a linear speed reduction takes place over a variable position range with a constant change in speed.

Description of the embodiments

The adjustment drive according to the invention is characterized by a reduction in speed and / or power after one predetermined functional relationship.

The given functional connection encompasses the whole Spectrum of continuous or discrete mathematical Functions. In addition to that later using the exemplary embodiment described linear course offers a reduction according to an e-function. This allows Realize acceleration and deceleration processes that one smooth transition between the two speed and / or Ensure performance levels. This can also be done by a decrease after a sine, cosine or Achieve tangent function and its inverse functions. Nth degree polynomials also prevent abrupt Transition, which increases the risk of jamming the Disc reduced. Representing here the functional relationships described refer to this Embodiment on a linear drop. The Explanations can be made on any functions transfer.

In Fig. 1 the speed variation of a first embodiment of the adjustment according to the invention with anti-trap schematically in a diagram. In this embodiment, a linear speed reduction takes place over a constant position range 10 with different changes in the speed of the moving part or the speed n of the motor used, which is preferably an electric motor. The power P or the speed n of the adjustment drive is recorded on the vertical axis. On the horizontal axis, the path x is plotted, which is traveled from the driven movable part to the fixed stop represented by the strong vertical line 11 in the "closed" position in the area of risk of pinching which is of interest in the context of the present invention, and up to position x0.

According to the embodiment, the power P or the speed n is reduced linearly in a specific position range, namely between x4 and x3, before reaching the “closed” position x0 to a minimum value p _min or n _min . There is a kind of target deceleration to position x3 at which the minimum value should be reached. This minimum value is then kept constant until the "closed" position is reached. It is so large that safe entry up to x0 is possible. This minimum value is advantageously empirically determined in each system in which the invention is used, taking into account the respective circumstances. This minimum value is chosen so large that a safe entry into the "closed" position x0 is possible under all circumstances. B. also taking into account different temperatures and humidity.

In the embodiment shown in FIG. 1, the specific position range 10 within which the lowering takes place has a constant length x4-x3, and the lowering of power P and / or speed n takes place with a different slope corresponding to the straight line 12 , 13 and 14 . The linear reduction ends when a certain position, namely x3, is reached. Then a minimum value for power P _min and / or speed n _{min is} reached. The slope is greatest on the straight line 12 , so that the rate of reduction of the power or speed reduction is also greatest. This straight line 12 starts at position x4 from maximum power P _max , which can correspond to the maximum supply voltage of the battery, for example, in a motor vehicle. The slope of the straight line 13 is less than that of the straight line 12 , so that the rate of lowering of the power or speed reduction is also lower. This straight line 13 starts at position x4 from a lower power P2, which can correspond, for example in a motor vehicle, to a battery supply voltage which is below the maximum. In the case of the straight line 14 , the incline is again smaller and the rate of lowering of the power or speed reduction is also smaller. This straight line 14 likewise starts at position x4, but from a power P1 which corresponds, for example in a motor vehicle, to an even lower supply voltage for the battery. The minimum power P _min can go hand in hand with the minimum permissible supply voltage. The linear reduction thus takes place in such a way that, regardless of the current supply power, it always starts at a specific position, namely x4. With a fixed position, namely x3, the reduction to the minimum value has ended. In this embodiment, the different current supply power is taken into account by the different slope of the straight line 12 , 13 , 14 , or in other words by the variable rate of change of the lowering.

In the embodiment, the diagram of which is shown schematically in FIG. 2, in the specific position range 10 , namely between position x4 and x3, the linear reduction to the minimum speed n _min or minimum power P _{min takes place} via variable reduction distances, their starting points being in Change depending on the current supply power, especially the supply voltage. The slope of the straight line 24 is constant, which corresponds to a constant rate of change of the lowering. The starting point for the start of the respective lowering changes in accordance with the differently high supply power, in particular the supply voltage of a motor vehicle battery. Since the lowering is completed at position x3, the lowering section designated 20 is the longest at maximum supply power P _max . Corresponding to the lower power P2, the associated lowering section 21 is shorter. The lowering section designated by 22 is even shorter, corresponding to the supply power P1, which is even smaller than P2. In this embodiment, the different current supply power is taken into account by the variable length of the lowering sections 20 , 21 , 22 with a constant rate of change of the lowering.

The adjustment drive designed according to the invention is expediently used in the “closed” position x0 together with a circuit for protection against jamming of foreign bodies between the moving part and the fixed stop, denoted by 11 in the figures. The lowering speeds resulting from the lowering according to the invention are small compared to those which are caused during the pinching processes. As a result, the actual pinch protection, in which the closing movement is stopped immediately and the direction of rotation is reversed if necessary, is essentially left unaffected. Since the straight line gradient of the reduction is known in each case, this can be taken into account in the calculation of the speed reduction by pinching processes by means of corresponding correction values. A suitable adaptive memory can be provided for the correction, in which self-learned difficulties of the system are stored. In this case, the linear controlled reduction in power and / or speed according to the invention is stored and stored as a slight stiffness. In contrast, when calculating the speed reduction by pinching, the pinch protection, the linear speed reduction is eliminated.

In the adjustment drive according to the invention, the Control of the speed or the power according to advantageous Design by semiconductor components, in particular in Form of a linear controller or a cycle controller with variable pulse-pause ratio. As a drive motor preferably an electric drive motor is used.

In a further embodiment of the invention, a additional improvement in the pinch protection evaluation can be achieved in that an increased resolution in the Path detection is used. This can be done using an EXOR link between two Hall sensors, which are 90 ° deliver phase-shifted position signals from the motor shaft, be done, thereby doubling the path accuracy is achievable. But it can also be combined with or alternatively using a multi-polarized magnetic ring respectively.

The adjustment drive according to the invention is used in particular for opening and closing windows and the sunroofs of motor vehicles. The position values given in FIGS. 1 and 2 can be x0 for x4 ≈ 500 mm, for x3 ≈ 50 mm, for x2 ≈ 25 mm and for x1 ≈ 4 mm in front of the "closed" position. For some applications, the position x2 with approx. 25 mm means the value at which the kinematic energy must in any case be reduced to such a still permissible value that the pinching forces fall below a certain value, for example less than 100 N, the Forces are measured on elastic rods, the spring rate of which is 65 N / mm. For this reason, the value for x3 is chosen to be ≈ 50 mm so that the reduction in speed and / or power to the minimum value is achieved in any case under the most unfavorable conditions at this predetermined limit value. With a clear width of less than about 4 mm, ie between positions x1 and x0, in the so-called sealing rubber area, the power P or the speed n can be increased again to the full power in order to obtain maximum closing forces. This is indicated in both figures by the reference numerals 15 , 16 , 17 , which are correspondingly assigned to the respective current powers P _max , P2 and P1.

By according to the invention according to a predetermined functional context designed lowering of the Speed of the adjustment drive to a minimum value of power and / or speed is the Rate of change known and predictable. This Lowering occurs either over a constant range away with one corresponding to the supply performance variable slope or with one of the utility power corresponding variable length or duration. In any case is optimized for a target point to the minimum value lowered. The one made by the invention Reduced power and / or speed caused Speed change is compared to that due to pinching processes evoked little. When combined with a circuit to protect against trapping, the prerequisite is therefore that because of the known rate of change, the Pinch protection, essentially unaffected, optimal and is effective independently.

Claims (11)

1. Adjustment drive with anti-trap protection for moving parts, such as windows and sunroofs in motor vehicles, in which a speed or speed reduction of the drive is provided in order to meet a predetermined spring rate in certain adjustment ranges (x2-x1) to reduce the kinematic energy, characterized in that that the drive is lowered according to a predetermined functional relationship within the predetermined range (x2-x1) before reaching the "closed" position (x0) the rotational speed (n) and / or the power (P) that the reduction to a Minimum speed (n _min ) within a certain position range ( 10 ) is that this minimum speed or minimum power is reached at a certain position (x3) before the "closed" position (x0), and that the minimum speed or minimum power is essentially constant is. 2. Adjustment drive according to claim 1, characterized in that the reduction takes place according to a predetermined functional relationship to the minimum speed or minimum power over a constant position range ( 10 ), the lowering speed ( 12 , 13 , 14 ) depending on the current supply power (P _max , P2, P1), in particular the supply voltage, changes. 3. Adjusting drive according to claim 1, characterized in that the reduction takes place according to a predetermined functional relationship to the minimum speed (n _min ) or minimum power (P _min ) over a variable position range ( 20 , 21 , 22 ), the starting point of which is in Dependency on the current supply power (P _max , P2, P1), in particular the supply voltage, changes. 4. adjusting drive according to one of claims 1 to 3, characterized in that the lowering is linear. 5. adjusting drive according to one of claims 1 to 3, characterized in that the lowering after the course an exponential function takes place. 6. Adjusting drive according to one of the preceding claims, characterized in that the necessary minimum speed (n _min ) or minimum power (P _min ) is empirically determined such that sufficiently high closing forces are guaranteed under all conditions, such as temperature and humidity in particular. 7. adjusting drive according to one of the preceding claims, characterized in that the control of the speed (s) or the power (P) of the preferably electrical Driven by semiconductor components, in particular Linear controller or clock controller with variable Pulse-pause ratio. 8. Adjusting drive according to one of the preceding claims, characterized in that it can be used in the "closed" position (x0) together with a circuit for protection against jamming of foreign bodies between the moving part and the fixed stop ( 11 ). 9. Adjusting drive according to one of the preceding claims, characterized in that when calculating the speed reduction by pinching the known slope ( 12 , 13 , 14 , 24 ) of the reduction according to a predetermined functional relationship of speed (s) and / or power ( P) the drive can be taken into account as a correction factor. 10. Adjustment drive according to claim 9, characterized characterized in that an adaptive memory for correction is provided in which the controlled lowering of Speed (n) and / or power (P) as minor Stiffness is saved. 11. adjusting drive according to one of the preceding claims, characterized in that the speed (s) and / or Power (P) when a very low clearance is reached Width, e.g. B. <4 mm, again to the greatest possible value can be increased to achieve maximum closing force especially in the area of sealing rubbers.