DE102014007444B4 - Adjusting method and adjusting device for adjusting a tailgate of a motor vehicle - Google Patents

Abstract

Method for adjusting a tailgate (2) of a motor vehicle (1), which can be adjusted between a closed position (4) and an open position (5), which has a height-adjustable chassis (10), wherein upon receipt of a tailgate opening command, the tailgate (2nd ) is adjusted into the open position (5), and- the chassis (10) is adjusted in height from a starting position (11) into a loading position (14), characterized in that- upon receipt of a tailgate closing command, the tailgate (2) is adjusted to the closed position (4) and the chassis (10) is reset from the loading position (14) to the starting position (11), the tailgate (2) being adjusted at the same time as the chassis (10), - that during the Closing movement of the tailgate (2) a motor variable of the flap servomotor is continuously compared with a reference variable and the closing movement is stopped or reversed when a predetermined difference threshold value between the motor variable and the reference variable is exceeded, - that in order to avoid an incorrect stop of the closing movement, a change in the motor variable due to the Height adjustment of the chassis (10) is taken into account by adjusting the reference variable or the predetermined difference threshold.

Description

The invention relates to an (actuating) method according to the preamble of claim 1 for adjusting a tailgate, which can be adjusted between a closed position and an open position, of a motor vehicle which has a height-adjustable chassis. Furthermore, the invention relates to an adjusting device according to the preamble of claim 4 for such a tailgate.

Modern (motor) vehicles are increasingly equipped with automatically opening and closing tailgates in order to increase the ease of use of the vehicle. Here and in the following, the term “tailgate” includes not only tailgates that are essentially vertically arranged in the closed position, as are customary in vans and caravans, but also trunk lids that are essentially horizontally arranged in the closed position, as are often used in sedans and coupes . Many vehicle variants - especially sedans and coupes - regularly have a loading sill that is higher than the floor of their trunk. In off-road vehicles (also referred to as SUVs, short for sports utility vehicles, or crossover SUVs) and conventional off-road vehicles (as well as station wagons), on the other hand, the loading sills are often lowered to the floor of the trunk. However, in these vehicle variants, the trunk floor is already arranged comparatively high relative to the ground due to their regularly high ground clearance. Thus, in general, loading the trunk with objects that are particularly heavy is cumbersome, since these objects first have to be raised to the height of the loading sill. Some vehicles therefore have an apron that borders the trunk at the rear of the vehicle and that can be folded down when the tailgate is open, so that the loading sill is lower and level with the trunk floor.

A method according to the preamble of claim 1 and an adjusting device according to the preamble of claim 4 are made DE 10 2010 038 967 B4 known.

Out of DE 10 2008 011 637 A1 a device for setting an open position of an upwardly pivoting tailgate of a motor vehicle is also known, wherein after the manual or motorized opening of a lock that locks the closed tailgate, the tailgate can be adjusted by motor into a preset open position and can be adjusted into a different open position via an actuating device . The actuating device has a switch with at least one actuating element, which, when moved from an initial position to an actuating position, causes a motorized adjustment of the tailgate continuously or step by step from one open position to another open position. Actuation of the actuation element in another actuation direction or actuation of another actuation element in a storage position causes the current open position of the tailgate to be stored, which is then a preset open position.

The object of the invention is to improve the comfort of use in a motor vehicle.

With regard to an actuating method for a tailgate of a motor vehicle, this object is achieved according to the invention by the features of claim 1. With regard to an actuating device for a tailgate of a motor vehicle, the object is achieved according to the invention by the features of claim 4 The invention is set out in the subclaims and the description below.

The adjusting method according to the invention is used to adjust a rear hatch, which can be adjusted between a closed position and an open position, of a (motor) vehicle—preferably a passenger car—that has a height-adjustable chassis. According to the invention, the tailgate is moved into the open position and (additionally) the height of the chassis is adjusted from an initial position to a loading position as part of the actuating method upon receipt of a tailgate opening command. The tailgate is preferably adjusted by means of a servomotor. In principle, however, the invention can also be used in a vehicle that is equipped with a tailgate that can be opened manually or by means of a mechanical opening mechanism.

Here and in the following, a “tailgate opening command” is understood to mean an adjustment command that is issued via a control element assigned to the vehicle for the purpose of adjusting the tailgate into its open position (ie for opening). Correspondingly, a “tailgate closing command” is the adjustment command that is aimed at closing the tailgate into its closed position. The control element is preferably a (radio) remote control (which is designed in particular as part of the vehicle key), a switch arranged on the vehicle and/or a sensor device, by means of which the issuance of the respective adjustment command is detected without contact (e.g. B. on the basis of a predetermined operating event that the vehicle user executes in the detection range of the sensor device). The adjustment, ie the opening and closing of the tailgate as well the height of the chassis is preferably adjusted in each case by means of an electric (rear) flap servomotor and by means of a chassis actuator. The chassis actuator is, for example, an electric servomotor or an air suspension actuator.

The initial position from which the chassis is moved to the loading position when the tailgate is opened is preferably a “neutral position” that the chassis assumes in the absence of special operating conditions, particularly when stationary or in an average driving situation. In the loading position, on the other hand, the chassis is preferably lowered. For example, the chassis is lowered to the maximum in the loading position, i.e. it is in its lowest position. In principle, it is conceivable within the scope of the invention for the chassis to be lowered only in the area of the rear of the vehicle (that is to say on the rear axle) in the loading position. However, the entire chassis (i.e. on the front axle and the rear axle) is preferably lowered. In an alternative embodiment, for example in the case of very flat motor vehicles, the loading position within the scope of the invention can also correspond to a chassis position that is higher than the starting position. In this case, the landing gear is raised when the tailgate is opened. In an expedient embodiment of the invention, it is provided in particular that the loading position can be taught in (and thus variably specified) in a user-specific manner—in particular in adaptation to the body size and usage habits of the vehicle user.

In the loading position, the loading and unloading of the trunk is recognized to be easier and the ease of use is thus increased. In particular, when the loading position is lowered, heavy objects do not have to be lifted up to the height of the loading sill of the trunk in the neutral position. This advantage is particularly important in vehicles with a trunk that is comparatively high compared to conventional vehicles, in particular off-road vehicles or SUVs. The latter often already include a height-adjustable chassis, so that this improvement in comfort can also be implemented with little effort.

Basically, within the scope of the invention, the tailgate and the chassis can be adjusted simultaneously into the open position or into the loading position. In an expedient configuration of the actuating method, however, the tailgate is only moved into the open position when the chassis is arranged in the loading position. This means that the tailgate is adjusted with a time offset to the chassis. This makes it easy to prevent the lowering of the running gear from colliding with the vehicle user (in particular his head) when the tailgate is open (in the event that he or she is already loading or unloading the trunk while the running gear is still being adjusted).

In the event that the open position of the tailgate (in particular its opening angle in the open position) can be specified in a user-specific (i.e. variable) manner, the tailgate can also be opened beyond the position specified (by the vehicle user) within the scope of the invention if the chassis is already in the possibly lowered loading position is arranged. As a result, the access to the trunk is advantageously increased if necessary. In this further opening of the tailgate, the height difference between the loading position and the neutral position is expediently taken into account in such a way that in the loading position the total height of the vehicle with the tailgate open does not exceed the corresponding total height of the vehicle in its neutral position. In the event that the vehicle is parked in a garage (or a multi-storey car park), this will prevent the tailgate from colliding with the garage ceiling (or multi-storey car park ceiling).

In an alternative variant of the method, the tailgate is first opened and then—that is, when the tailgate is arranged in the open position—the chassis is adjusted to the loading position. In this case, during the adjustment of the chassis, at least the space in front of the tailgate in the adjustment direction is monitored for an obstacle, preferably by means of a non-contact anti-trap device, with the adjustment of the chassis being stopped if an obstacle is detected in this monitored space.

In both method variants with time-delayed opening of the tailgate or adjustment of the chassis, the opening or adjustment is expediently triggered upon receipt of a start signal. This start signal is output, for example, by a limit switch which is actuated by the tailgate in the open position or by the chassis in the loading position. Alternatively, an end signal of the flap servomotor or the landing gear partial drive is used as the start signal, which is output by a controller assigned to the flap servomotor or the chassis actuator at the end of the respective adjustment.

According to the invention, upon receipt of the command to close the tailgate (issued by the vehicle user), the tailgate is moved into the closed position and the chassis is raised again from the loading position. The chassis is preferably in the position in which it was arranged before lowering, in particular adjusted back to the neutral position.

The tailgate and the chassis are adjusted at the same time, in particular the tailgate is closed and the chassis is raised. In this case, preferably during the closing movement of the tailgate--as part of an anti-trapping device that is regularly present in an automatically adjustable tailgate--a motor variable of the flap servomotor that is characteristic of the adjusting movement is continuously compared with a reference variable. The closing movement is stopped or reversed when a predetermined difference threshold value is exceeded, based on the difference between the motor variable and the reference variable, which indicates a case of pinching, i.e. an object being trapped between the tailgate and the vehicle frame. If the chassis and tailgate are adjusted at the same time, a (particularly negative) acceleration of the tailgate is now taken into account by adapting the reference variable or the specified difference threshold value in order to avoid an incorrect stop of the closing movement. The tailgate is known to experience such an acceleration when the adjustment of the chassis begins or ends during the closing movement.

Here and in the following, a motor variable is referred to as a characteristic motor variable that contains quantitative information, in particular about the speed of the adjustment movement, so that the speed can be clearly read from the motor variable. The motor variable is preferably an actual speed, in particular of the shaft of the flap servomotor. Alternatively, the motor variable is a motor current taken up by the flap actuator motor, from which the motor torque and/or the actual speed can in turn be calculated. The reference variable is accordingly a setpoint speed (in particular dependent on the position of the tailgate along its adjustment path), a setpoint current or a setpoint torque.

In the variant of the method described above, in which the tailgate and the chassis are adjusted simultaneously, the setpoint speed is preferably reduced as a function of the start or end of the chassis adjustment, or the permissible difference between the actual speed and the setpoint speed is increased.

The adjusting device according to the invention is set up and provided for use with the adjustable tailgate described above on the vehicle. The vehicle also has the height-adjustable chassis. To adjust the tailgate, the actuating device includes the flap servomotor. Furthermore, the adjusting device comprises a control unit which is set up to carry out the adjusting method described above, in particular automatically. In other words, the control unit is set up to move the tailgate to the open position (i.e. to control the flap servomotor to close) and to adjust the chassis to the loading position on receipt of a tailgate opening command. The control unit is expediently also set up to close the tailgate and reset the chassis to the starting position on receipt of the tailgate closing command.

Within the scope of the invention, the control unit can be designed as a non-programmable electronic circuit (e.g. as an ASIC) and can be integrated, for example, in a controller for the flap servomotor. However, the control unit is preferably formed by a microcontroller in which the functionality for carrying out the adjustment method according to the invention is implemented in the form of a software module. In this case, this software module can in particular form a component of an overarching control software (firmware) for controlling the flap servomotor.

In principle, it is conceivable within the scope of the invention for the control unit to be set up to communicate with a chassis control unit assigned to the chassis actuator via a central control system (in particular the bus system) of the vehicle. In an expedient embodiment, however, the control unit is directly coupled to the chassis control unit in terms of signal transmission when installed in the vehicle as intended. This means that when the tailgate opening command (or closing command) is received, the control unit of the actuating device transmits a signal for adjusting the chassis directly to the chassis control unit.

• 1 in schematischer Seitenansicht das Heck eines Kraftfahrzeugs mit einer automatisch verstellbaren, in einer Schließstellung angeordneten Heckklappe und einem höhenverstellbaren Fahrwerk, und
• 2 in Ansicht gemäß 1 das Kraftfahrzeug mit geöffneter Heckklappe.

Exemplary embodiments of the invention are explained in more detail below with reference to a drawing. Show in it:

• 1 a schematic side view of the rear of a motor vehicle with an automatically adjustable tailgate arranged in a closed position and a height-adjustable chassis, and
• 2 in view according to 1 the motor vehicle with the tailgate open.

Corresponding parts are always provided with the same reference symbols in all figures.

In 1 the rear of a (motor) vehicle 1 is shown. The vehicle 1 includes a tailgate 2, which is set up to open the interior, in particular the trunk 3, of the vehicle 1 (see Fig. 2 ) to close. The tailgate 2 is automatic and reversible between a closed position 4 and an in 2 shown open position 5 adjustable. In order to adjust the tailgate 2, the vehicle 1 has an adjusting device 6, which has a (rear) lid adjusting motor 7 (designed as a spindle motor, see Fig. 2 ) having.

The vehicle 1 is an SUV with a height-adjustable chassis 10. The latter is in normal operation, ie z. B. arranged in a neutral position 11 during a city trip and / or without intervention of the vehicle user (driver). For a sporty driving style, e.g. B. to achieve a more stable driving behavior in curves and/or when driving fast, the chassis 10 can be lowered out of the neutral position 11 in response to a control command from the vehicle user. For driving on unpaved roads and/or in rough terrain, the chassis 10 can also be raised out of the neutral position 11 in order to achieve greater ground clearance.

The actuating device 6 also has a control unit 12 for controlling the flap actuating motor 7 . In terms of signal transmission, the control unit 12 is coupled directly to the flap actuator motor 7 and to the chassis 10, specifically to a controller for a chassis actuator, which is not shown in detail. Furthermore, the control unit 12 has an operating element (not shown in detail) by means of which the vehicle user can issue an adjustment command directed to opening or closing the tailgate 2 . The operating element is a (hardware) switch, for example, which is arranged on the outside of the tailgate 2 . Alternatively, the operating element is a sensor device which, for. B. detects a movement of the vehicle user by means of capacitive sensors. In the latter case, the control unit 12 checks whether the movement corresponds to a predetermined operating event and, if there is sufficient agreement, evaluates the movement as an adjustment command. The control unit 12 is also set up to carry out an adjustment method which is described in more detail below.

Upon detection of the adjustment command and with the tailgate 2 closed (arranged in the closed position 4), the control unit 12 evaluates the adjustment command as a tailgate opening command. The control unit 12 then emits a lowering signal A to the chassis 10 . The chassis 10 is then lowered (by means of the chassis actuator) by a stroke X from the neutral position 11 into a loading position 14 . In this loading position 14, the chassis 10 is in the lowest possible position, so that the rear and thus a loading edge 16 of the trunk 3 is arranged at a reduced distance from the ground compared to the neutral position 11 ( 2 ). As soon as the chassis 10 is arranged in the loading position 14 , the chassis 10 (or its chassis actuator) outputs a loading position signal L to the control unit 12 . This then emits an opening signal O to the flap servomotor 7 . The tailgate 2 is moved into the open position 5 under the action of the actuating force of the flap servomotor 7 . Consequently, the tailgate 2 is adjusted with a time delay in relation to the chassis 10 .

When the tailgate 2 is open, the control unit 12 evaluates the renewed actuation of the operating element (ie a new adjustment command) as a tailgate closing command and then outputs a closing signal S to the flap servomotor 7 . As soon as the tailgate 2 is in its closed position 5, the control unit 12 outputs a lifting signal H to the running gear 10, so that the running gear 10 is raised by the stroke X back into the neutral position 11.

According to another (also based on 1 and 2 illustrated) embodiment of the actuating method, the tailgate 2 is first opened in response to the tailgate opening command and an end signal E is output by the flap servomotor 7 to the control unit 12 in the open position 5 . In response to this end signal E, the control unit 12 outputs the lowering signal A to the chassis 10 .

In an optional embodiment of the adjusting device 6 , the chassis height corresponding to the loading position 14 can be variably specified (taught) by parameterizing the control unit 12 . The loading position 14 can in particular also be taught in such a way that it corresponds to a chassis position that is higher than the neutral position 11 .

The subject matter of the invention is not limited to the exemplary embodiments described above. Rather, further embodiments of the invention can be derived by the person skilled in the art from the above description. In particular, the individual features of the invention and their design variants described with reference to the various exemplary embodiments can also be combined with one another in other ways.

Reference List

1

motor vehicle

2

tailgate

3

trunk

4

closed position

5

open position

6

actuator

7

tailgate actuator

10

landing gear

11

neutral position

12

control unit

14

loading position

16

sill

A

lowering signal

X

hub

L

loading position signal

O

opening signal

S

closing signal

H

lifting signal

E

end signal

Claims (5)

Method for adjusting a tailgate (2) of a motor vehicle (1), which can be adjusted between a closed position (4) and an open position (5), which has a height-adjustable chassis (10), wherein upon receipt of a tailgate opening command - the tailgate (2nd ) is adjusted into the open position (5), and - the running gear (10) is adjusted in height from a starting position (11) into a loading position (14), characterized in that - upon receipt of a tailgate closing command, the tailgate (2) is adjusted to the closed position (4) and the chassis (10) is reset from the loading position (14) to the starting position (11), the tailgate (2) being adjusted at the same time as the chassis (10), - that during the Closing movement of the tailgate (2) a motor variable of the flap servomotor is continuously compared with a reference variable and if a predetermined difference threshold value between the motor variable and the reference variable is exceeded, the closing movement is stopped or reversed, - that to avoid an incorrect stop of the closing movement, a change in the motor variable due to Height adjustment of the chassis (10) is taken into account by adjusting the reference variable or the predetermined difference threshold. procedure after claim 1 , wherein the tailgate (2) is only moved into the open position (5) when the chassis (10) has arrived in the loading position (14). procedure after claim 1 , The chassis (10) being adjusted in height into the loading position (14) only when the tailgate (2) is arranged in the open position (5). Adjusting device (6) for a tailgate (2) of a motor vehicle (1) that can be adjusted between a closed position (4) and an open position (5) and has a height-adjustable chassis (10), - with a tailgate servomotor (7) for adjusting the tailgate ( 2), - with a control unit 12 which is adapted to the adjustment method according to one of Claims 1 until 3 to perform. Adjusting device (6) after claim 4 , wherein the control unit 12 in the intended installation state in the motor vehicle (1) is directly coupled to a chassis control unit in terms of signal transmission.

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