DE19861342B4 - Window raiser with clamp protection for motor vehicle has spring element in cable run under tension during closing; retains spring movement reserve during closing with no obstruction - Google Patents

Abstract

The pull chord window raiser has a motorized drive (1) for raising and lowering a window that acts on a rotatable cable drum (5) and reels in and out two connected cable runs (3,4) of a pull cable (2). A clamp protection arrangement stops and reverses the motor if the window encounters and obstruction when closing. A spring element (12) arranged in the cable run to which tension is applied during closing has a spring constant so that at least part of a spring displacement reserve is retained during closing with no obstruction and is used if an obstruction is encountered.

Description

The invention relates to a method for determining a spring constant D _{F of} a spring element to be arranged in a drive train of a cable-operated window lifter, wherein a control and regulating electronics of the drive without spring element shuts off within a predetermined by a first test standard reaction path and optionally reversed, when the closing force of the disc exceeds a predetermined limit.

Furthermore, the invention relates to a cable pull window according to the preamble of claim 5.

State of the art

Such a window is for example from the DE 196 18 853 C1 known. In this case, springs whose spring characteristic are dimensioned such that when closing the disc without occurrence of an obstacle at least a part of a spring travel reserve is maintained, which is at least partially used up in a disc closing movement with obstacle springs in Antriebseilstrang the cable pull. Such an anti-trap is used to prevent danger, such as pinching a hand, a finger or the like. Body part between the window and the door frame of the motor vehicle. Window regulators with anti-trap protection therefore have to meet strict test standards, which differ considerably, for example, in Europe and the USA.

According to these standards, the closing force of the window regulator drive must not exceed 100 N when the disc hits an obstacle. To test this standard, a test specimen is clamped between the upper edge of the window and the door frame. The test specimen consists of a spring whose spring constant moves according to the European requirements in the value range between 10 N / mm and 20 N / mm. At the lower limit, this means that a control and regulating electronics for driving the window lifter within a reaction time in which the window has covered a distance of about 10 mm, detect the obstacle and possibly has to reverse the drive. In the case of the upper limit value of 20 N / mm for the Prüffederkonstante the reaction distance is reduced even to only 5 mm. Meanwhile, even in the US stricter requirements apply. Thus, it is required that the test spring should have a spring constant of 65 N / mm and the closing force must not exceed 100 N. Accordingly, the control electronics of the drive must respond within a reaction distance of less than 1.5 mm. To meet this criterion, there is a possibility to increase the sensitivity of the control and regulating electronics, since an armature rotation of the currently used drive motor already performs a disc lift of 2 mm. Another possibility is the use of another engine with a higher ratio gear, what u. U. may involve the use of a new control electronics. Both solutions therefore lead to a redesign of the drive and thus at considerable cost.

From the DE 693 09 807 T2 is a window with a anti-trap for switching off and optionally reversing the drive when hitting the disc on an obstacle in the closing path known. For this purpose, a coil spring is arranged coaxially to the cable of the window, wherein the coil spring is supported with its one end to a fixed plate and with its opposite end to an element which is intended by the cable by friction against this against the restoring force of the spring to be moved. The formed as a tubular member member has a side foot, which cooperates with a contact of an electrical switch. The switch is attached to a fixed support. As long as the load that the cable must transmit when lifting the window pane, does not exceed a predetermined value corresponding to the biasing force of the spring, the cable keeps the tubular member in such a position in which the lateral foot actuates the electrical switch. If, however, due to the occurrence of an obstacle in the closing path of the window, the load exceeds a predetermined value by the bias of the spring, the rohrförmmige part moves with the side foot against the restoring force of the spring, which is consequently compressed. Thus, the electric switch is no longer operated by the side foot, so that the change of the switching state of the electric switch can be used to initiate a command to reverse the direction of rotation of the motor.

problem

In these known pull-wire window regulators the response time of the safety circuit is not large enough to meet stringent requirements. In addition, in the window according to the DE 693 09 807 T2 the frictional resistance between the tubular part and the rope over the operating life of the window, in particular taking into account the harsh conditions under certain circumstances, change, so that this and in itself too high reaction time of the known window lifter beyond not even reproducible or largely constant.

Based on this, the present invention seeks to provide a method for determining a spring constant D _F according to the preamble of claim 1, in which, while maintaining the control and regulating electronics, which meets the first test standard, the window even while maintaining a second, more stringent test standard can be used. Furthermore, the invention has the object, a cable winch of the type mentioned in such a way that while maintaining the current drive stricter requirements for the anti-trap, such as valid in the US, are met.

Invention and advantageous effects

The method, the object is achieved by the features specified in claim 1, device-wise by a cable window with the features specified in claim 5. Advantageous embodiments of the invention are specified in the subclaims.

Thereafter, a spring element is arranged with such a spring constant in the strand, on which when closing the disc a tensile force is exerted by the drive, that when closing the disc without the occurrence of an obstacle at least a part of a spring travel reserve is maintained, which in the disc closing movement with obstacle is at least partially used up. Through this consumption of the spring travel reserve of the spring element when the disc hits an obstacle, an extension of the reaction path and thus the reaction time for detecting the obstacle and reversing the drive is achieved. The value of the extension of the reaction path and reaction time drops according to the value of the existing spring travel reserve, which may be, for example, 10 mm. This means that stricter requirements for anti-trap protection, in particular the test standards applicable in the USA, can also be met with current drives and open-loop or closed-loop control electronics. The normal closing movement of the disc without the occurrence of an obstacle remains without influence, since the spring element is not stressed here.

According to claims 6 and 7, the spring element on a spring force which is greater than the resulting from the weight of the disc and the friction forces occurring during displacement of the disc displacement force and smaller than the force exerted on the cable strand when closing the disc from the drive train. This ensures that the spring element when closing the disc, in the event that no obstacle in the closing path is present, remains in a relaxed or almost relaxed position, so that the full spring travel reserve for the extension of the reaction time is available in case of danger. Only when engaging the disc in the seal of the door frame and reaching the upper end position, the spring element u. U. compressed to block, which additionally causes a cushioning of the disc and a play-free closing. In this case, a limit position detection of the closed position of the disc is possible because, for example, on the drive a characteristic profile of the motor current can be measured.

The spring constant D _{F of} the spring element can be derived from the equation: 1 / D _total = 1 / D _norm + 1 / D _F where D _{norm is} the spring constant of a test specimen known from a test standard for anti-pinch protection and D _total indicates the resulting spring constant, which results when the test spring and spring element are connected in series. This equation describes the series connection of two springs, namely the spring element and the test spring. This ensures that the resulting spring constant D _{total can be selected} in a range controllable for the current drive and its control and regulating electronics, for example between 10 N / mm and 20 N / mm. For determination, first for D _total the lower limit of 10 N / mm and for D _Norm a value for the spring constant of the test specimen, for example. 65 N / mm according to the US test standard, inserted into the equation and then the upper permissible value for determines the spring constant of the spring element D _F. In the case where the upper limit value of 20 N / mm is used for D _total in the equation and the value for the test spring constant D _{norm is} maintained, the lower permissible value for the spring constant of the spring element D _{F is obtained} .

According to another advantageous embodiment of the invention, a spring for a rope length compensation is arranged in the rope strand on which a tensile force is exerted when opening the disc. As a result, a consistent effect of the anti-trap protection is achieved because a possibly occurring rope slack is removed from the entire cable by the spring.

A design according to claim 8 structurally simple and advantageous embodiment of the invention is that the spring element and the spring are supported at one end to a housing of the drive and the other end on the front side of the associated cable strand respectively surrounding hose. This allows the use of the invention in cable winches with closed loop rope.

embodiment

An embodiment will be explained below with reference to the drawing.

The single FIGURE shows a possible embodiment of the cable pull window regulator according to the invention for motor vehicles with anti-trap protection. To close and open the (not shown) disc wraps a motor drive 1 two about a rotatable in a housing 9 stored cable drum 5 interconnected rope strands 3 . 4 a cable 2 back and forth. The two rope strands 3 . 4 run outgoing from the cable drum housing 9 in each case an outer rope hose 15 to a trained as a role reversal 8th , Thereafter, the two strands of rope extend 3 . 4 each parallel to a guide rail 6 , On these rails 6 is each a taker 7 led to holding the disc, which with the associated cable strands 3 . 4 are connected. By turning the rope drum 5 in one direction or the other there is a pulling movement of one or the other strand of rope 3 . 4 connected with an up and down movement of the driver 7 and thus to an opening and closing movement of the disc.

In the rope strand 4 on which when opening the disc from the drive 1 a tensile force is exerted, there is a spring 13 which is located between the housing 9 of the drive 1 and on the front side of the associated cable hose 15 supported. The feather 13 is used to rope length compensation when a ropeless, so that constant balance of power in the cable 2 are ensured.

In the rope strand 3 is between the case 9 of the drive 1 and the associated rope hose 15 a spring element 12 arranged, the spring constant is selected such that it has a spring reserve when closing the window.

This spring travel reserve serves to extend the reaction path and thus the reaction time for detecting an obstacle in the closing path of the disc. This makes it possible to comply with the same window regulator both the European standard for anti-trap protection and the currently much stricter US standards.

According to the European standards for anti-trap protection, a test spring, the spring constant of which can move between the values 10 N / mm and 20 N / mm, is clamped between the upper edge of the window and the door frame of a motor vehicle, the closing force of the wheel and thus the traction of the vehicle drive 1 on the rope strand 3 a value of 100 N may not exceed. For the previous anti-trap protection without spring element 12 in the claimed during the closing movement to train rope strand 3 This means that the control electronics at the lower limit of 10 N / mm within a distance of about 10 mm has time to detect the obstacle and the drive 1 to reverse. In the case of a test feather constant of 20 N / mm, the reaction distance is reduced to only 5 mm. It is now required in the USA that the test spring constant should have a value of 65 N / mm and that the closing force must not exceed a value of 100 N. This means that the control electronics of the drive 1 must respond within a reaction distance of less than 1.5 mm. This requirement is not met with the previous anti-trap or only after considerable costs for a more sensitive control electronics and / or a motor with higher transmission ratio.

By doing that in the rope strand 3 , on which a tensile force is exerted when closing the disc, which is based on a spring travel reserve spring elements 12 is used, the reaction path and thus the reaction time for the anti-trap protection is extended. The closing movement of the disc is stopped until the spring travel reserve of the spring element 12 is used up. In the embodiment chosen here, the spring travel reserve can be up to 10 mm, so that a sufficient reaction path for the current control electronics of the drive 1 is present and thus meets the more stringent requirements of 65 N / mm for the spring test rate from the USA.

To the spring constant for the spring element 12 The following equation is used for two series-connected springs; 1 / D _total = 1 / D _norm + 1 / D _F ;

D _{Total is} the spring constant resulting from the series connection of two springs, D _{Norm is} the test spring constant and D _{F is} the spring constant of the spring element 12 in the rope strand 3 ,

To determine the upper permissible value for the spring constant D _{F of} the spring element 12 is for D _total the lower for the control electronics of the current drive 1 controllable limit of 10 N / mm previously used and for D _standard, for example, the test spring rate according to the US guidelines of 65 N / mm. Accordingly, the lower permissible value for the spring constant D _{F of} the spring element results 12 for D _total the upper controllable limit for the current electronics of 20 N / mm is used. Thus, the more stringent requirements from the USA can be fulfilled even with the window lifter with control electronics for anti-trap protection designed for the European test standards, if the spring constant of the spring element in the cable strand 3 has a range of values between about 12 N / mm and 29 N / mm.

Of course, the spring force of the spring element 12 be sized so that it is greater than the resulting from the weight of the disc and the reaction forces occurring when moving the disc displacement force and smaller than that when closing the disc from the drive 1 on the rope strand 3 applied traction. This ensures that the spring element 12 when closing the disc without occurrence of an obstacle in the closing path, apart from the area in which the disc enters the seal of the door frame is not or almost not compressed. Only when the disc engages in the region of the seal of the door frame and reaches the upper end position, the spring element 12 claimed by the drive-side tensile force to pressure and u. U. in blocking position, so that a stop attenuation is reached. In this case, a characteristic curve of the motor current can be measured, so that a limit position detection of the closed position of the disc is made possible. Characterized in that the spring force of the spring element 12 greater than the force resulting from the disc and the frictional forces in an upward movement, causes the spring element 12 also a play-free closing of the disc. Because after reaching the upper end position and a decay of the tensile force on the disc, the spring element relaxes 12 until the disc by the then predominant spring force of the spring element 12 back to its original position, ie pushed back to its closed position.

The method, the object is achieved by a method having the features of claim 1. The control electronics is assigned the first test standard as D _total and with the aid of the second, stricter test standard the spring constant D _F is calculated using the equation 1 / D _total = 1 / D _norm + 1 / D _F ; determined, so that by a manufactured according to this method cable window also the second, stricter test standard is met.

According to the device, the object is achieved by the features specified in claim 5. Advantageous embodiments of the invention can be found in the subclaims.

LIST OF REFERENCE NUMBERS

1

drive

2

cable

3

cable strand

4

cable strand

5

cable drum

6

Rail driver

8th

idler pulley

9

drive housing

12

spring element

13

feather

15

cable hose

Claims (9)

Method for determining a spring constant D _F in a drive train of a motor drive ( 1 ) provided cable pull-window lifter to be arranged spring element ( 12 ), starting from the cable window lifter without spring element ( 12 ) and a control and regulating electronics, which the drive ( 1 ) shuts down within a predetermined by a first test standard reaction path and possibly reversed when the closing force of the disc exceeds a predetermined limit, to meet a second, stricter test while maintaining the control and regulating electronics of the cable window regulator without spring element ( 12 ) in the drive train, the spring constant D _F of the arranged in the drive train spring element ( 12 ) from the equation 1 / D _total = 1 / D _norm + 1 / D _F is determined by for D _total the spring constant of a test specimen for the first test standard and for D _norm the spring constant of a test specimen for the second, stricter test standard is used. A method according to claim 1, characterized in that the closing force of the disc does not exceed a predetermined limit of 100 N. A method according to claim 1 or 2, characterized in that the spring constant of the test specimen of the first test standard is between 10 N / mm and 20 N / mm. Method according to one of the preceding claims, characterized in that the spring constant D _{standard of} the test specimen of the second, stricter test standard is 65 N / mm. Cable pull window lifter with a spring element (according to one of Claims 1 to 4) ( 12 ) in the drive train. Cable pull window lifter according to claim 5, in particular for motor vehicles with a motor drive ( 1 ) for lifting and lowering the disc, which on a rotatably mounted cable drum ( 5 ) and two associated cable strands ( 3 . 4 ) of a cable ( 2 ) and with a pinch protection for switching off and possibly Reversing the drive ( 1 ) upon impact of the disc on an obstacle in the closing path, wherein at least the one strand of rope ( 3 ), on which when closing the disc, a tensile force from the drive ( 1 ) in a rope hose ( 15 ) to the drive ( 1 ) is guided, the drive side on a spring element ( 12 ), which between rope hose ( 15 ) and a fixed abutment, for example a housing ( 9 ) of the drive ( 1 ), wherein the spring constant of the spring element ( 12 ) Is dimensioned such that when closing the disc without the occurrence of an obstacle at least part of a spring travel reserve is maintained, which is at least partially used up in the disc closing movement with obstacle, the closing force of the disc does not exceed a predetermined limit and a control electronics of the Drive ( 1 ) within a limited reaction distance, in which the window lift has traveled a maximum predetermined by a first test standard distance, detects an obstacle in the displacement path of the disc, characterized in that the spring element ( 12 ) has a spring constant D _F , which is determined from Equation 1 / D _total = 1 / D _norm + 1 / D _F , where D _{Norm is} a prescribed for the anti-trap spring constant of a test spring a second stricter test standard in which the control and Control electronics of the drive ( 1 ) within a reaction distance, in which the window has covered a maximum of a second, stricter test standard given distance, detects an obstacle in the displacement of the disc, the resulting spring constant D _total of a test spring for the first test standard. Cable pull window lifter according to claim 5 or 6, characterized in that the spring element ( 12 ) has a spring force which is greater than that resulting from the weight of the disc and the friction forces occurring during displacement of the disc resulting displacement force. Cable pull window lifter according to one of claims 5 to 7, characterized in that the spring element ( 12 ) has a spring force, which is smaller than that when closing the disc from the drive ( 1 ) on the rope strand ( 3 ) applied traction. Cable pull window lifter according to one of claims 5 to 8, characterized in that the spring element ( 12 ) has a spring constant D _F , which is determined from the equation 1 / D _total = 1 / D _norm + 1 / D _F , where D _{Norm is} the spring constant of a test spring known from a test standard for anti-pinch protection and D _total indicates the resulting spring constant , which in series connection of test spring and spring element ( 12 ).

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