US-12618278-B2 - Method for detecting a pinching situation when moving a movable component

US12618278B2US 12618278 B2US12618278 B2US 12618278B2US-12618278-B2

Abstract

A method for detecting a pinching situation when moving an adjustable component for closing an opening by means of an electric motor in a vehicle comprises the following steps: providing a trigger threshold for a closing force exerted by the electric motor on the component or a physical variable on which it is based, with which the electric motor is operated, for at least one movement position of the component within a travel path available to it for the movement; moving the component into the movement position; determining a current value of the closing force or of the physical variable on which it is based for the at least one movement position; comparing the current value and the trigger threshold; and outputting a trigger signal which indicates the pinching situation dependent from the result of the comparison.

Inventors

Verena Bachschneider
Julian T. Dittrich
Lorenz Casper

Assignees

Webasto SE

Dates

Publication Date: 20260505
Application Date: 20240510
Priority Date: 20230511

Claims (11)

1 . A method for detecting a pinching situation when moving an adjustable component for closing an opening by means of an electric motor in a vehicle, comprising the steps: providing a trigger threshold for at least one of: a closing force, which is exerted by the electric motor on the adjustable component, and a physical variable, on which the closing force is based, with which the electric motor is operated, for at least one movement position of the adjustable component within a travel path available to the component for the movement; moving the adjustable component into the movement position; determining a current value of at least one of the closing force and the physical variable on which the closing force is based for the at least one movement position; comparing the current value and the trigger threshold; outputting a trigger signal which indicates the pinching situation dependent from a result of the comparison step; determining a time period over which the adjustable component was continuously held in other movement positions up to a point in time of the movement of the adjustable component into the at least one movement position, wherein in each of the movement positions within the travel path other than the at least one movement position, the opening is not in a state closed by the adjustable component, and adapting at least one of the provided trigger threshold and the determined current value, wherein, when the provided trigger threshold is adapted, the provided trigger threshold is increased, dependent from the determined time period, to generate an adapted trigger threshold, and wherein, when the determined current value is adapted, the determined current value is decreased, dependent from the determined time period, to generate an adapted current value relative to the predefined trigger threshold; and using at least one of: the adapted trigger threshold and the adapted current value in the step of comparing the current value and the trigger threshold, respectively.
2 . The method for detecting a pinching situation according to claim 1 , further comprising: reversing the adjustable component dependent from the trigger signal.
3 . The method for detecting a pinching situation according to claim 1 , wherein the determination of the time period comprises: querying a first time stamp at which the adjustable component was last moved out of a completely closed position by operating the electric motor; querying a second time stamp at which the adjustable component reaches or begins to reach the at least one movement position by operating the electric motor during a current closing movement; and calculating the time period from the first time stamp and the second time stamp.
4 . The method for detecting a pinching situation according to claim 1 , wherein carrying out, if a first time period is determined, at least one of: a first adaptation of the trigger threshold and the current value, which leads to a first difference with respect to the provided trigger threshold, and carrying out, if a second time period is determined which is greater than or lasts longer than the first time period, at least one of: a second adaptation of the trigger threshold and the current value, which leads to a second difference with respect to the provided trigger threshold, wherein the second difference is greater than the first difference.
5 . The method for detecting a pinching situation according to claim 1 , wherein defining within the travel path available to the adjustable component for the movement a predetermined section of the travel path in which the adjustable component may come into contact with the at least one seal, the at least one seal being provided at or near an opening of the vehicle, which at least one seal is in close contact with the component in the closed state, in order to seal or at least protect a vehicle interior with respect to an outside; and carrying out at least one of: adapting the trigger threshold and adapting the current value depending on whether the at least one movement position of the adjustable component lies within the predetermined section of the travel path.
6 . The method for detecting a pinching situation according to claim 1 , wherein setting different values for the trigger threshold at different movement positions along the travel path.
7 . The method for detecting a pinching situation according to claim 1 , wherein calculating at least one of: the adaptation of the trigger threshold and the current value using a formula based on (a) at least one of: the provided trigger threshold and from the determined current value, and (b) a term to be added having a linear dependence on the determined time period.
8 . The method for detecting a pinching situation according to claim 1 , wherein the adjustable component is a roof of a vehicle selected from any one of a sunroof, a sliding roof, and a glass roof and a opening of the vehicle is configured in the frame of the vehicle that can be closed by the roof of the vehicle.
9 . A device for detecting a pinching situation when moving an adjustable component for closing an opening by means of an electric motor in a vehicle, comprising: first module unit, which is configured to operate the electric motor, to detect a pinching situation in the process and to control the electric motor as a function of the detection in order to reverse the adjustable component, wherein the first module unit is further configured: to receive a trigger threshold for at least one of a closing force, which is exerted by the electric motor on the adjustable component, and a physical variable, on which the closing force is based, with which the electric motor is operated, for at least one movement position of the adjustable component within a travel path available to it for the movement; to move the adjustable component into the movement position by operating the electric motor; to obtain at least one of: a current value of the closing force and the physical variable on which the current value of the closing force is based for the at least one movement position; to compare the current value and the trigger threshold; and to output a trigger signal which indicates the pinching situation dependent from the result of the step of comparing and with which the closing operation of the adjustable component is switched to its reversing operation; second module unit, which is configured: to read in at least one of: a trigger threshold and at least one of: a current value of the closing force and the physical variable on which the current value of the closing force is based for the at least one movement position; to determine a time period over which the adjustable component was held in other movement positions up to a point in time of the movement of the adjustable component into the movement position, in which the opening was continuously not closed by the adjustable component; to adapt, to at least one of: to increase the trigger threshold dependent from the determined time period, and to decrease the current value dependent from the determined time period relative to the read-in trigger threshold; and to transmit at least one of: the trigger threshold, which has been adapted, and the current value, which has been adapted, to the first module unit.
10 . The method for detecting a pinching situation according to claim 8 , wherein the electric motor is a DC motor, in particular a DC motor or a brushless DC (BLDC) motor.
11 . The method for detecting a pinching situation according to claim 8 , wherein the electric motor is a brushless DC (BLDC) motor.

Description

CROSS-REFERENCE TO RELATED APPLICATION This application claims priority to German Application No. DE 10 2023 204 396.3 filed on May 11, 2023, which is incorporated herein by reference in its entirety for all purposes. TECHNICAL FIELD Various aspects relate to a method for detecting a pinching situation when moving a movable component for closing an opening by means of an electric motor in a vehicle. Further aspects thus relate to a corresponding device. TECHNICAL BACKGROUND Motor vehicles regularly include windows or sliding or sunroofs as electrically driven components that are adjustable in order to close or open the corresponding window or roof openings. More recently, the same has thus been true for tailgates or sliding doors as electrically adjustable components. As this may lead to accidents in the sense that body parts such as arms, hands, fingers, legs or a head can be undesirably trapped between the respective component and at the edge of the opening in question, technical standards have been created in many countries that require the vehicle manufacturer to implement anti-trapping or anti-pinching protection measures. In particular, anti-pinching protection must be set up in a manner that the body part in question is detected as a pinched object during a respective closing movement. This type of detection is usually carried out by monitoring a force applied to close the opening or to move the component, or a corresponding quantity during the closing process. In the case of electric window regulators or sunroof motors, many of the technical standards mentioned require a value of 100 N as a limit for the maximum force (i.e. clamping force) that can be applied to an object or part of the body without causing injury etc. In practice, therefore, a triggering threshold that is often well below this limit value is usually applied to ensure reliable detection and that the limit value is not exceeded. If a force exerted on the component during the closing process exceeds this trigger threshold, it can be concluded that an object is present on the remaining section of the component's travel path to close the opening. It should also be noted that the closing force is made up of the force exerted on the component during the closing process as well as friction and deformation forces generally acting against it and, where applicable, wind and roof loads, etc. The closing force is therefore generally larger than the force exerted on the component during the closing process, i.e., the clamping force. For example, an electric control may often provide for control of the drive in such a way that the component maintains a constant speed or motor speed, for example, or at least a correspondingly specified profile during the closing process (motor speed control as an example). If, for example, a mechanical resistance increases due to friction on a section of the travel path of the component that is to be passed, the relevant motor control unit may, for example, readjust the voltage or power supply of the electric motor in order to overcome the resistance by increasing the closing force with the aim of maintaining the specified speed. In this respect, there are regular fluctuations in the closing force over the travel path of the component that is to be passed. Such fluctuations, which are not related to actually trapped objects, are usually taught in the system and generally do not pose a problem. The motor speed may be determined, for example, with the help of position sensors, in particular Hall sensors, or by measuring a voltage curve, etc. Even with motors which are not speed-controlled, a closing force or the corresponding clamping force may be inferred by determining a motor speed, for example. Detection is therefore based on the monitoring of a physical quantity that reflects the curve of the motor torque over the current position of the movable component (e.g., the roof system), that is closing force over travel path, and a comparison of this quantity with a stored reference curve, that is closing force over travel path. As soon as the currently determined physical quantity exceeds the stored reference value by more than a definable trigger threshold, the system detects a pinching entity and triggers a reversing movement. This means that the closing process is stopped immediately and the component is moved back a few centimeters to at least partially release the opening so that the object or body part can be pulled out unharmed. In general, the closing force itself is not determined by sensors to detect a pinching situation, but is calculated using physical quantities associated with the operation of the electric motor. For example, the force exerted by the motor depends linearly on the voltage with which the motor is supplied, e.g. via PWM control (PWM: pulse width modulation), and/or the rotational or angular speed at which the rotor rotates. The closing force can be calculated from this using other known, f