Windscreen wiper arrangement and method for testing the functionality of a windscreen wiper arrangement of a means of transport

Abstract

A windshield wiper assembly (1) and a method for testing the functionality of a windshield wiper assembly (1) of a means of transport (10) are proposed. The method comprises the following steps: controlling an electronically commutated electric motor (2), hereinafter referred to as "EC motor (2)", of the windshield wiper assembly (1) using an electrical signal, determining a response of the windshield wiper assembly (1) to the control, and determining the functionality of the windshield wiper assembly (1) based on the response.

Description

State of the art

[0001] The present invention relates to a windshield wiper assembly and a method for testing the functionality of a windshield wiper assembly of a means of transport. In particular, the present invention relates to an improved assurance of the functionality and / or improved mobility of the means of transport.

[0002] Windshield wipers are safety-relevant components of a vehicle because they can ensure visibility of the traffic situation under difficult conditions. Therefore, the current state of the art sometimes proposes to carry out an initial test sequence to check the functionality of the windshield wiper at the start of a journey or in response to an "ignition on" signal. Due to the hardware used in the current state of the art, this inherently results in a twitching or brief movement of the windshield wiper. This movement can be annoying to the user or be perceived by them as a defect or at least as having a detrimental effect on the vehicle's quality. Current state of the art uses electric motors for this purpose, sometimes followed by a worm gear to enable high torques to be achieved with electric motors.

[0003] The electric motors are controlled by electrical signals via a control unit. The electrical energy comes from the vehicle's on-board electrical system. To test the control electronics, the initial (and final) check is carried out to identify as many error sources as possible to ensure functionality while driving. Since the movement caused by the check can be detrimental in the current state of the art, it is usually important to perform the test during the entry process to avoid the user having to pay particular attention to the movement. During the test process, also known as the "pre-drive" check, the motor is controlled for a predetermined time until the motor performs a movement. The functionality—i.e., the response of the motor, transmission, or wipers—is tested using electrical sensors, position sensors, or similar devices.

[0004] It is an object of the present invention to provide a discreet and unobtrusive test of the functionality of a windshield wiper assembly. A further object of the present invention is to achieve the highest possible confidence in the functionality of the windshield wiper assembly over the course of an operating cycle.

[0005] The above-mentioned object is achieved according to the invention by a method having the features according to claim 1 and by a windshield wiper arrangement having the features according to claim 12. The subclaims show preferred developments of the invention.

[0006] According to the method according to the invention, the functionality of a windshield wiper assembly of a means of transport, which can be configured as a car, van, truck, motorcycle, aircraft, and / or watercraft, is tested. The functionality test is carried out in particular at a customer's facility or not during production of the means of transport. In particular, the functionality test can be carried out at the beginning of the life cycle of the means of transport. In other words, the test process is carried out once or multiple times between the start of use (e.g., after the end of a parking period) and the next parking / stopping and leaving of the means of transport. In a first step, an electrically commutated electric motor, also referred to as an EC motor, is controlled by an electrical signal from the means of transport.In other words, the EC motor is supplied with electrical energy to drive the windshield wiper assembly, or at least to supply the EC motor with electrical energy. The response of the windshield wiper assembly to the activation is then determined. This can be done, as in the prior art, using sensors (position sensor, current sensor, voltage sensor, magnetic field sensor, or similar). In a third step, the functionality of the windshield wiper assembly is determined based on the response. For example, the windshield wiper assembly can be classified as OK, and operational readiness can optionally be signaled. If it is not functioning properly, a signal can be issued to the user of the vehicle and / or an error log entry can be made.In addition, if functionality is not present, a new test process can be initiated to rule out the impact of a singularity on the test result. The windshield wiper assembly can be provided for a front window / windshield of a means of transport. Alternatively or additionally, a windshield wiper assembly according to the invention can be provided for a rear window or another window of a means of transport. The windshield wiper assembly can comprise a single windshield wiper or multiple windshield wipers, which are moved by respective EC motors or coupled via a gear / rod. Alternatively or additionally, a windshield wiper assembly within the meaning of the present invention can also be provided for cleaning lighting devices (e.g., a headlight, a low beam, or the like), a camera, or a sensor for autonomous driving.Due to the fact that an EC motor typically has a comparatively high-resolution position diagnostic system, significantly smaller movements of the windshield wiper assembly or the windshield wiper can lead to an analyzable result. This can minimize user irritation or even eliminate any user irritation, thereby increasing or improving the quality impression of the means of transport equipped with the invention.

[0007] The EC motor can drive a worm gear. The EC motor's axis / rotor is coupled to a spindle, via which an output from the windshield wiper assembly can move the wiper blade in different directions. This allows high wiping torques to be generated, and position diagnostics of the EC motor's rotor can be used to provide particularly insightful information about the wiper blade's exact position.

[0008] Optionally, it can first be determined that the EC motor is not currently being used (or no longer being used) to move a windshield wiper of the windshield wiper assembly. In other words, the windshield wiper is not currently being used (or no longer being used) (i.e., "ready for operation"). For this purpose, for example, a manual or sensor-assisted shutdown of the EC motor or the windshield wiper assembly can be detected. In other words, it is determined that the windshield wiper assembly is not currently needed due to the operating state of the means of transport. In response to this, the EC motor can be controlled according to the above steps of claim 1. In other words, the EC motor is supplied with electrical energy to carry out / initiate the claimed functionality test. Alternatively, switching off the windshield wiper assembly could start a timer, after which the test process according to the invention is initiated again.A further alternative is to (cyclically) test for an event after the windshield wiper assembly has been switched off, upon which the test process according to the invention is triggered again. For example, this can be determined by detecting precipitation and / or a predefined ambient temperature being undershot and / or a predefined vibration / acceleration signal being detected, which could, for example, result from driving on a rough road. The aforementioned events can, individually or cumulatively, degrade the functionality of the windshield wiper assembly, so that the functionality test according to the invention can expediently be performed in response to the event.Even in this situation, the use of an EC motor allows for an imperceptible / non-detectable movement of the windscreen wiper assembly from the user's perspective to be used to electrically or sensor-basedly determine the reaction of the windscreen wiper assembly for the test process.

[0009] The reaction can be determined, for example, as an electrical parameter using a current sensor / voltage sensor or similar. In particular, the reaction can be compared with a predefined reference during the functionality determination process, which can specify an absolute value (amplitude, frequency, etc.) of the detected signal (reaction of the windshield wiper assembly). Alternatively or additionally, a characteristic of a time signal of the reaction of the windshield wiper assembly or of the electrical value, the position sensor signals, or similar, can be compared with a predefined reference. For example, this can include a time period oriented towards the duration of a single wiping operation or be based on this. In particular, a sensor arranged in the EC motor can be used to determine the reaction of the windshield wiper assembly to the control. For example, a magnetic field sensor can be used here, which detects the rotation of the rotor of the EC motor.If this movement does not occur, it can be concluded that the control was unsuccessful and the windshield wiper assembly is not available. Otherwise, the (expected) response can lead to the conclusion that the windshield wiper assembly is ready or functional. In particular, the response can be detected as an electrical parameter based on a phase current or a coil current of the EC motor. In particular, if the EC motor has multiple phases (two, three or more phases), an electrical parameter can be detected at two, three or more coils of the EC motor. In the course of this, any bridge used to operate the EC motor (e.g. B6 bridge) is also checked and its functionality is ensured.

[0010] In the case of multiple electrical phases, the EC motor can be controlled as follows, for example, to reduce or avoid any irritation for the user: a first electrical variable can be impressed into a first electrical phase, while a second electrical variable can be impressed into a second electrical phase of the same EC motor. Both electrical variables are dimensioned and oriented in such a way that opposing torques result from the first electrical phase and the second electrical phase. This generates a resultant torque which is, for example, zero in magnitude, but at least smaller than the torque resulting from the first electrical phase or the second electrical phase.In other words, the two torques cancel each other out, at least partially, which means that comparatively high electrical currents can be used for a comparatively long time to test the windshield wiper assembly without making the visibility of the windshield wiper movement unnecessarily high.

[0011] If a third electrical phase is included in the EC motor, a third electrical variable can be impressed into the third electrical phase, particularly for simultaneous testing of the third electrical phase, and a third torque can be generated, which reduces the effect of the first resulting torque. The second resulting torque generated in this way is again smaller in magnitude than the first resulting torque or zero. In this way, movement of the windshield wiper or wiper blade can be completely dispensed with, although an electrical test of the bridge arrangement controlling the windshield wiper assembly and the electrical phases of the EC motor is carried out. Only a mechanical blockage of the wiper blade cannot be detected by a second resulting torque of 0 Nm.

[0012] The first and / or second resulting torque can be < 5 Nm, in particular < 2 Nm, and most preferably 0 Nm. Under normal conditions, the aforementioned torques do not result in a movement of the windshield wiper that is perceptible to the user, since the frictional forces to be overcome are always higher. Therefore, the functionality of the windshield wiper assembly can be tested repeatedly throughout the life cycle of the vehicle without unnecessarily distracting or irritating the driver.

[0013] The phases are therefore preferably controlled alternately in such a way that no rotating field is created and therefore no torque.

[0014] Reactivating the EC motor during a life cycle of the vehicle can result in defects or blockages of the wiper blade occurring during travel being detected and reported in good time before the need for operation of the windshield wiper assembly arises. Thus, the driver can receive a message, in response to which they can reduce their travel speed or otherwise eliminate the need for operation of the windshield wiper assembly. When reference is made to a "life cycle" of the vehicle in this disclosure, this refers in particular to a period of time that characterizes continuous operation of the vehicle. In other words, leaving or locking the vehicle is understood as the end of a life cycle and the (potential) beginning of a new life cycle.In other words, an uninterrupted period between an "ignition-on" event and a subsequent "ignition-off" event can be understood as the life cycle of the means of transport.

[0015] Alternatively or additionally, a first life cycle and a second life cycle of the means of transport can be separated from one another by a sleep process of the on-board electrical system of the means of transport. The terminal status of the means of transport can determine whether a life cycle has ended or begun. During a life cycle of the means of transport defined in this way, several test processes according to the invention are optionally carried out, which are carried out in particular (at least in part) while the means of transport is traveling (travel speed greater than 0 or less than 0 km / h), regardless of the operating state of the windshield wiper system (e.g. due to rain). The renewed control of the EC motor during the life cycle can be based on a predefined time period (timer of one minute, five minutes, ten minutes, or similar).) since an immediately preceding activation process and / or due to information received externally (particularly via the Internet) (e.g., from a weather database) and / or due to the occurrence of an event detected by sensors in the vehicle. In this way, depending on the probability that a defect in the windshield wiper assembly has occurred in the meantime, a new test process can be carried out in accordance with the present invention. Unnecessary test processes or test processes that are highly unlikely to yield any new findings can be avoided in this way.

[0016] The occurrence of the event can be detected, for example, using a rain sensor on the vehicle and / or an acceleration sensor on the vehicle and / or a temperature sensor on the vehicle. In particular, digital map material or a road surface condition represented in this map material (off-road, field track, gravel path, country road, speed bumps, or joints) can also be detected, in response to which the test can be initiated or a time interval for a repeated test can be adjusted.

[0017] The electrical signal can be dimensioned such that the wiper blade of the windshield wiper assembly does not sweep over a small angle of 4°, in particular 2°, preferably 1°, particularly preferably 0.2°, which is essentially imperceptible at a glance. This ensures that the user's perception of the movement is insignificant or even non-existent.

[0018] According to a second aspect of the present invention, a windshield wiper assembly is proposed, which comprises a windshield wiper, in particular two windshield wipers, an electronically commutated electric motor (EC motor), and a control unit (e.g., a programmable processor, microcontroller, or similar). In this way, the windshield wiper assembly is configured to control the EC motor of the windshield wiper assembly by means of an electrical signal, thereby preventing any movement of the windshield wiper that is irritating or even perceptible to the user. Furthermore, the control unit is configured to determine a response of the windshield wiper assembly to the control. The response can represent a movement or the measurability or measurement result of an electrical variable in the windshield wiper assembly. Finally, the control unit is configured to determine the functionality of the windshield wiper assembly based on the response.Functionality is categorized, so to speak, by classifying the windshield wiper as "available" or "unavailable." Steps generally known in the prior art for informing a user, a workshop, or a vehicle operator and / or making an error log entry can follow in a generally known manner. Short description of the characters

[0019] Embodiments of the invention are described in detail below with reference to the accompanying drawings. In the drawing: Fig. 1 a perspective view of a front section of a means of transport with an embodiment of a windscreen wiper arrangement according to the invention; Fig. 2 a perspective detailed view of an EC motor usable according to the invention for an embodiment of a windscreen wiper arrangement according to the invention; and Fig. 3 a flowchart illustrating steps of an embodiment of a method according to the invention for testing the functionality of a windshield wiper arrangement of a means of transport. Embodiments of the invention

[0020] Preferably, all identical components, elements and / or units in all figures are provided with the same reference numerals.

[0021] Fig. 1 shows a perspective view of the front end of a means of transport 10 in the form of a passenger car. A windshield wiper 3 of the windshield wiper assembly is driven by an EC motor 2 via a linkage. The EC motor 2, in turn, is supplied with power by a three-phase bridge assembly within a control unit 8. The bridge assembly has three phases 12, 13, 14, the currents to which can be determined as a reaction by means of a respective current sensor 11. Furthermore, the means of transport 10 has a rain sensor 4, a temperature sensor 6, and a 3D acceleration sensor 5. Using the aforementioned sensors, events can be detected, based on which the need for a renewed execution of a test procedure according to the invention for the functionality of the windshield wiper assembly 1 can be determined.During the test process, the three phases 11, 12, 13 of the EC motor 2 are controlled in opposite directions such that the resulting torque of the EC motor 2 is less than would be required to overcome the frictional forces of the windshield wipers 3. This prevents movement of the windshield wipers 3, although a thorough test of the electrical and electronic components of the windshield wiper arrangement 1 according to the invention can be carried out. In other words, the phases 12, 13, 14 and the other current-carrying components are checked for functionality without the user (not shown) being irritated or distracted by movement of the windshield wipers 3. An alternative trigger for carrying out the inventive test of the functionality of the windshield wiper arrangement 1 can be determined via the Internet 7. For example,A rough road can be detected, for which a location of the vehicle 10 reveals that corresponding digital map material suggests travel on an off-road route. The resulting vibrations increase the probability of a malfunction of electrical and mechanical components of the vehicle, so that the time interval until the test procedure according to the invention is repeated until the vehicle leaves the off-road route can be reduced.

[0022] Fig. 2 shows a perspective detailed view of the EC motor 2. The EC motor 2 has three electrical phases 12, 13, 14, the currents of which can be determined in terms of magnitude and direction via current sensors 15, 16, 17. In addition, the individual torques 18, 19, 20 resulting from the respective currents are shown, wherein the torques 18, 19 result in a first resulting torque 21 and, with additional consideration of the torque 20, a second resulting torque 22. The first resulting torque 21 is smaller in magnitude than both the torque 18 and the torque 19. The second resulting torque 22 is the smallest torque in the illustration and is preferably close to 0. In particular, however, the second resulting torque 22 does not lead to a visible movement of the windshield wiper that moves the windshield wiper further than 4°, preferably further than 2°, extremely preferably further than 0.4°.

[0023] Fig.3 shows a flowchart illustrating steps of an embodiment of a method according to the invention for testing the functionality of a windshield wiper assembly of a means of transport. In step 100, it is determined that the EC motor of the windshield wiper assembly is not being used to move a windshield wiper of the windshield wiper assembly. In other words, it is determined, in particular, that the windshield wiper has currently neither been requested by the user nor categorized as required by sensors. The windshield wiper assembly is therefore in a deactivated operating state or at least in a sleep mode. Such a state can be determined, for example, by the manual or automatic deactivation of the windshield wiper and, in particular, by the elapse of a predefined period of time since the aforementioned process.In step 200, the electrically commutated motor of the windshield wiper assembly is then controlled or "energized" by means of an electrical signal. In other words, a signal is applied to the electrical connections of the EC motor, which preferably applies a current to a plurality, most preferably all, of the phases of the EC motor. In contrast to the conventional operation of the windshield wiper assembly, it can be provided that the individual phases are energized in such a way that the resulting torques are smaller than in the conventional operation of the windshield wiper assembly. In step 300, a response of the windshield wiper assembly to the control is determined. For example, electrical variables, the signals of a position sensor, or magnetic variables within the windshield wiper assembly can be detected and classified.In step 400, the functionality of the windshield wiper assembly is then determined based on the reaction, or conversely, it is determined that the windshield wiper assembly is not functioning. A signal representing the (non-)functionality of the windshield wiper assembly can then be output to a user, a workshop, and / or an operator of the means of transport, and / or a corresponding entry can be written to a memory of the means of transport. Due to the fact that the inventive use of the EC motor results in a movement / energization of the windshield wiper assembly that is difficult to detect or completely imperceptible from the user's perspective, a repeated test of the functionality of the windshield wiper assembly can be carried out during continued operation of the means of transport without this reducing the quality impression of the means of transport designed according to the invention.The method according to the invention can then be executed again, wherein step 100 can be skipped or replaced by an event-based determination of the need for re-execution.

Claims

[1] Method for testing the functionality of a windscreen wiper arrangement (1) of a means of transport (10), comprising the steps: - controlling (200) an electronically commutated electric motor (2), hereinafter referred to as “EC motor (2)”, of the windscreen wiper arrangement (1) by means of an electrical signal, - determining (300) a reaction of the windscreen wiper arrangement (1) to the control and - Determining (400) the functionality of the windscreen wiper arrangement (1) based on the reaction. [2] Method according to claim 1, wherein the EC motor (2) drives a worm gear. [3] The method of claim 1 or 2, further comprising: - Determining (100) that the EC motor (2) is not used to move a windscreen wiper (3) of the windscreen wiper arrangement (1). [4] Method according to one of the preceding claims, wherein the reaction is determined as an electrical characteristic, in particular based on a phase current. [5] Method according to one of the preceding claims, wherein the electrical signal has a first electrical phase (12) and a second electrical phase (13), in particular also a third electrical phase (14). [6] Method according to claim 5, wherein the control (200) comprises: Memorize - a first electrical quantity (15) in the first electrical phase (12) and - a second electrical variable (16) in the second electrical phase (13) for generating opposing first and second torques (18, 19) for generating a first resultant torque (21). [7] The method of claim 6, further comprising: - impressing a third electrical variable (17) in the third electrical phase (14) to generate a third torque (20) acting opposite to the first resulting torque (21), wherein the first torque (18), the second torque (19) and the third torque (20) together represent a second resulting torque (22). [8] Method according to claim 6 or 7, wherein the first resulting torque (21) is less than 5 Nm, in particular less than 2 Nm. [9] Method according to one of the preceding claims further comprising: - renewed control (210) of the EC motor (2) due to - a predefined time elapsed since a previous activation and / or - information received from outside and / or - the occurrence of a sensory-detected event. [10] Method according to claim 9, wherein the occurrence of the event is detected by means of - a rain sensor (4) and / or - an acceleration sensor (5) and / or - is determined by means of a temperature sensor (6). [11] Method according to one of the preceding claims, wherein the electrical signal is dimensioned such that a wiper blade of the windscreen wiper arrangement (1) does not sweep over an angle of 4°, in particular of 2°, preferably of 1°. [12] Windscreen wiper arrangement (1) comprising: - a windscreen wiper (3), - an electronically commutated electric motor (2), hereinafter referred to as “EC motor (2)”, - a control unit (8) which is arranged - to control the EC motor (2) of the windscreen wiper arrangement (1) by means of an electrical signal, - to determine a reaction of the windscreen wiper arrangement (1) to the control and - to determine the functionality of the windscreen wiper arrangement (1) based on the reaction.

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