Steering device for a vehicle, vehicle and method for operating a steering device

Abstract

Steering device (100) for a vehicle (500), wherein the steering device (100) has a steering rod (110), wherein the steering rod (110) has at least partially on its outer side a rack structure (140) which can be coupled or is coupled to a servo drive (115) in order to transmit a steering movement from the servo drive (115) to the steering rod (110), and wherein the steering rod (110) is at least partially designed as a spindle nut (200) in order to transmit a steering movement performed by a driver to the steering rod (110) via a threaded rod (145) guided in the spindle nut (200), wherein the spindle nut (200) has an internal thread (205) the length of which corresponds within a tolerance range to a length of the rack structure (140).

Description

[0001] The present approach relates to a steering device for a vehicle, a vehicle and a method for operating a steering device.

[0002] There are steering systems that operate by means of a permanently maintained oil flow. This flow is generated by a pump driven by the vehicle's internal combustion engine. DE 101 42 599 A1 discloses a steering system for vehicles in which a steering movement applied by a steering shaft to a steering gear is transmitted to a rack.

[0003] German patent application DE 10 2015 118 292 A1 discloses a steering gear for a vehicle, a vehicle, a method for controlling a steering gear, and a method for steering a vehicle. The steering gear comprises a steering device for a vehicle, wherein the steering device has a steering rod, wherein the steering rod has at least partially on its outer surface a rack and pinion structure that can be coupled to or is coupled to a servo drive in order to transmit a steering movement from the servo drive to the steering rod, or wherein the steering rod is at least partially designed as a spindle nut in order to transmit a steering movement performed by a driver to the steering rod via a threaded rod guided in the spindle nut.

[0004] Publication DE 10 2010 053 581 A1 discloses an EPS system for a commercial vehicle.

[0005] Against this background, the objective of the present approach is to create an improved steering device, an improved vehicle, and an improved method for operating a steering device.

[0006] This problem is solved by a steering device having the features of claim 1.

[0007] The advantages achievable with the presented approach are that a steering device with a steering rod is created that can enable a simple and flexible transmission of steering movements from different sources.

[0008] A steering device according to the approach presented here for a vehicle includes a steering rod. The steering rod has, at least partially on its outer surface, a rack and pinion structure that can be coupled to, or is coupled to, a servo drive to transmit a steering movement from the servo drive to the steering rod. The steering rod is at least partially designed as a spindle nut to transmit a steering movement performed by a driver to the steering rod via a threaded rod guided in the spindle nut.

[0009] The steering system can, for example, be a device for changing the orientation of the wheels and thus changing the direction of travel. For instance, the direction of travel can be changed in response to a steering movement by the driver via a steering wheel. The steering system can also be understood as a device that assists the driver in steering the vehicle in the desired direction. The servo drive can be understood as a drive that assists the driver in changing the direction of travel, enabling the driver to change direction effortlessly or with minimal effort. The steering column can be designed as an interface to transmit the steering movement initiated by the driver and the steering movement initiated by the servo drive to the steering column.By designing the steering rod as a spindle nut, the steering input from the driver can be efficiently received and linked to the steering input induced by the servo drive. The approach presented here can be used in the field of motor-assisted manual inputs, specifically in automotive engineering when a servo drive or steer-by-wire system assists a manual steering system.

[0010] The approach presented here can also be understood as a linear electronic power steering system, or EPS (Electronic Power Steering) with externally applied assistance. In other words, the approach presented here can be understood as a steering system, preferably an electromechanical steering system (EPS), or alternatively, a steer-by-wire system. Advantageously, the assistance can be applied only when needed, thus enabling a power-on-demand system. Furthermore, the approach presented here can reduce the vehicle's CO2 emissions and eliminate the need for a conventional recirculating ball steering system. Additionally, the assistance force can be selectively controlled via a control unit, independent of driver input. This can be used for safety-relevant systems such as lane keeping assist.Further measures, such as automatic counter-steering in the event of a tire blowout, compensation for crosswinds, and similar functions, are easily achievable through the combination of additional vehicle sensors and targeted control of the auxiliary motor. A key aspect of this electronic power steering system is that the steering input, whether manual or servo-motorized, is applied directly to a pushrod. This allows for both cost savings and optimized installation space, as power transmission can be achieved without the use of a steering column lever (also known as a pitman arm) and a ball joint.

[0011] According to one embodiment, the steering device can include an angle drive designed to transmit the steering movement from a steering wheel to the steering column. The angle drive can, for example, couple a steering column and a steering column. The integration of an angle drive advantageously allows for a compact design requiring minimal installation space.

[0012] According to a further embodiment, the rack and pinion structure of the steering rod and, additionally or alternatively, a gear of the servo drive can have helical teeth. Advantageously, helical teeth enable quiet and low-friction operation of the steering rod and / or the gear. Furthermore, helical teeth can ensure a smooth transmission of torque.

[0013] According to another embodiment, the servo drive can be configured to perform a steer-by-wire function and, additionally or alternatively, a steering movement controlled by a driver assistance function. This also allows the advantages of the approach described here to be realized very efficiently.

[0014] According to a further embodiment, the spindle nut can have an internal thread whose length, within a tolerance range, corresponds to the length of the rack and pinion structure. Advantageously, the internal thread can guide the threaded rod, thus ensuring reliable operation of the spindle nut. The fact that the spindle nut and the rack and pinion structure have the same length, within a tolerance range of, for example, 10 percent, ensures that the steering movements are linked over a very large steering angle range.

[0015] Furthermore, an embodiment of the approach presented here is advantageous as a vehicle that incorporates an embodiment of a steering device mentioned herein. This also allows the advantages of the approach described here to be realized very efficiently.

[0016] According to a further embodiment of the approach presented here, a method for operating an embodiment of a steering device mentioned herein is presented, which includes a step of controlling a servo drive to move the steering rod using the rack and pinion structure. This also allows the advantages of the approach described here to be realized very efficiently.

[0017] This process can be implemented, for example, in software or hardware, or in a hybrid form of software and hardware, for example in a control unit.

[0018] The approach presented here also creates a control unit that is designed to execute, control, or implement the step of a variant of the procedure presented here in a corresponding device. This implementation variant of the approach, in the form of a control unit, also allows the underlying task to be solved quickly and efficiently.

[0019] For this purpose, the control unit can have at least one processing unit for processing signals or data, at least one storage unit for storing signals or data, at least one interface to a sensor or actuator for reading sensor signals from the sensor or for outputting data or control signals to the actuator, and / or at least one communication interface for reading or outputting data embedded in a communication protocol. The processing unit can be, for example, a signal processor, a microcontroller, or the like, while the storage unit can be flash memory, an EPROM, or a magnetic storage device.The communication interface can be configured to read or output data wirelessly and / or via wired connections, whereby a communication interface that can read or output wired data can, for example, read this data electrically or optically from or output it into a corresponding data transmission line.

[0020] In this context, a control unit can be understood as an electrical device that processes sensor signals and outputs control and / or data signals accordingly. The control unit can have an interface, which can be implemented in hardware and / or software. In the case of a hardware-based interface, the interfaces can, for example, be part of a so-called system ASIC, which incorporates various functions of the control unit. However, it is also possible that the interfaces are separate integrated circuits or at least partially comprised of discrete components. In the case of a software-based interface, the interfaces can be software modules, which, for example, are located on a microcontroller alongside other software modules.

[0021] In an advantageous embodiment, the control unit controls a steering device for a vehicle.

[0022] Examples of the approach presented here are explained in more detail in the following description with reference to the figures. These show: Fig. 1 a schematic representation of a steering device according to an exemplary embodiment with servo drive, steering wheel and wheels connected thereto; Fig. 2 a schematic representation of a section of a steering device according to an exemplary embodiment; Fig. 3 a flowchart of an embodiment of a method for operating a steering device; Fig. 4 a block diagram of an exemplary embodiment of a control unit for operating a steering device; and Fig. 5 a schematic representation of an exemplary embodiment of a vehicle with a steering device presented here.

[0023] In the following description of favorable embodiments of the present approach, the same or similar reference numerals are used for the elements shown in the various figures and which have a similar effect, without repeating these elements.

[0024] Fig. Figure 1 shows a schematic representation of an embodiment of a steering device 100 for a vehicle with a servo drive, steering wheel, and wheels connected to it. The vehicle is, for example, a motor vehicle such as a passenger car, a motorcycle, a commercial vehicle, or the like. The steering device 100 is designed, for example, to enable a driver to steer the vehicle. For example, the steering device 100 can be operated by a servo drive located in the Fig. 1. The vehicle's driver (not shown) can operate the controls manually, for example by means of a steering wheel 105.

[0025] The steering device 100 comprises a steering rod 110, a servo drive 115 with, for example, a motor 120, a bevel gear 125, and a push rod 130. The push rod 130 is, for example, coupled to a vehicle tire 155 or wheels.

[0026] According to one embodiment, the angle drive 125 is designed to transmit the steering movement from the steering wheel 105 to the steering rod 110 with a change in direction of action and is arranged between the steering rod 110 and the steering column 150.

[0027] According to one embodiment, the motor 120 is arranged on the servo drive 115, which can also be referred to as a servo gear. The servo drive 115 includes, for example, a gear 135. The steering rod 110 has a rack structure 140, which can also be referred to as a rack or piston, partially on its outer surface. The gear 135 is designed and arranged, for example, to engage with the rack structure 140. This couples the servo drive 115 to the rack structure 140. According to one embodiment, the rack structure 140 of the steering rod and / or the gear 135 of the servo drive 115 can also have helical teeth. The steering rod 110 is thus designed to transmit a steering movement from the servo drive 115 to the steering rod 110.Furthermore, the steering rod 110 is designed as a spindle nut to transmit a steering movement performed by the driver to the steering rod 110 via a threaded rod 145 guided in the spindle nut. This means that an internal thread is provided in the steering rod 110 into which another component can engage. At the same time, the steering rod 110 is secured against rotation, so that, on the one hand, a reliable engagement between the servo drive 115 and the rack and pinion structure 140 is ensured, and on the other hand, the threaded rod 145, which engages in the internal thread designed as a spindle nut, can also effect a linear movement of the steering rod 110.

[0028] According to one embodiment, the steering rod 110 and the steering wheel 105 are coupled to each other via a steering column 150. According to an alternative embodiment, the servo drive 115 is configured to perform a steer-by-wire function and / or steering movements controlled by a driver assistance function.

[0029] According to one embodiment, a connecting element 160, which can also be referred to as a connection, connects the push rod 130 and the steering rod 110 to each other.

[0030] In other words, the approach presented here is an electromechanical steering module, or alternatively a steer-by-wire system, in which, on the one hand, a steering movement entered by a driver via a steering wheel 105 is transmitted to this system, and on the other hand, a steering movement can be introduced into the same system via a servo drive 115. For this purpose, the steering device 100, which can also be referred to as a steering module, is partially designed as a steering rod 110, which can also be referred to as a rack or piston, with a rack structure 140, which can also be referred to as a toothed section, applied to one outer surface. The servo drive 115 engages with this toothed section and transmits corresponding movements to this steering rod 110.Inside the steering rod 110 is a threaded rod 145, which can also be referred to as a spindle drive, through which the movement applied by the steering wheel 105 is transmitted to the steering rod 110. The steering rod 110 thus serves as an interface to transmit the steering movement applied manually by the driver and the steering movement applied by the servo drive 115 to the steering system.

[0031] Fig. Figure 2 shows a schematic section of a steering device 100 according to an exemplary embodiment. This can be an exemplary embodiment based on Fig. The steering device described in section 1 is involved.

[0032] According to one embodiment, the steering rod 110 is partially designed as a spindle nut 200. The threaded rod 145 is arranged within the spindle nut 200, which can also be referred to as a spindle. In other words, the threaded rod 145 is guided within the spindle nut 200. The spindle nut 200 is designed, for example, to transmit a steering movement performed by the driver to the steering rod 110 via the threaded rod 145.

[0033] The spindle nut 200 has a rack and pinion structure 140 on its outer circumference. For example, the rack and pinion structure 140 is designed as a helical toothing and extends along the length of the spindle nut 200. According to one embodiment, the spindle nut 200 has an internal thread 205, the length of which corresponds to a length of the rack and pinion structure 140. The internal thread 205 is designed, for example, to guide the threaded rod 145.

[0034] Fig. Figure 3 shows a flowchart of an embodiment of method 300 for operating a steering device. The steering device corresponds to or is similar to the steering device shown in one of the figures described herein. Method 300 includes a step 305 for controlling a servo drive to move the steering rod using the rack and pinion mechanism.

[0035] Fig. Figure 4 shows a block diagram of an exemplary embodiment of a control unit 400 for operating a steering device. The control unit 400 is designed to execute the method from Fig. 3 or a similar procedure. The control unit 400 has a unit 405 for controlling a servo drive to move the steering rod using the rack and pinion structure. The control unit 405 is configured to perform and / or control the actuation step.

[0036] Fig.Figure 5 shows a schematic representation of an embodiment of a vehicle 500. The vehicle 500 has the steering device 100 and the control unit 400. The steering device 100 and the control unit 400 correspond to or resemble the steering device and the control unit from each of the figures described herein. The steering device 100 and the control unit 400 are connected to each other in a way that enables signal transmission.

[0037] If an embodiment includes an “and / or” connection between a first feature and a second feature, this is to be read as meaning that the embodiment according to one embodiment has both the first feature and the second feature, and according to another embodiment either only the first feature or only the second feature. REFERENCE MARK LIST 100 Steering device 105 steering wheel 110 handlebar 115 Servo drive 120 engine 125 angle drive 130 push rod 135 gear 140 rack and pinion structure 145 threaded rod 150 steering column 155 vehicle tires 160 connecting element 200 spindle nut 205 internal thread 300 methods for operating a steering device Step 305 of the approach 400 Control unit for operating a steering device 405 Unit for controlling 500 vehicles

Claims

[1] Steering device (100) for a vehicle (500), wherein the steering device (100) has a steering rod (110), wherein the steering rod (110) has at least partially on its outside a rack structure (140) which can be coupled or is coupled to a servo drive (115) in order to transmit a steering movement from the servo drive (115) to the steering rod (110), and wherein the steering rod (110) is at least partially designed as a spindle nut (200) in order to transmit a steering movement performed by a driver to the steering rod (110) via a threaded rod (145) guided in the spindle nut (200), wherein the spindle nut (200) has an internal thread (205) the length of which corresponds within a tolerance range to a length of the rack structure (140). [2] Steering device (100) according to claim 1, comprising an angle drive (125) designed to transmit the steering movement from a steering wheel (105) to the steering rod (110). [3] Steering device (100) according to one of the preceding claims, wherein the rack structure (140) of the steering rod (110) and / or a gear (135) of the servo drive (115) has helical teeth. [4] Steering device (100) according to one of the preceding claims, wherein the servo drive (115) is configured to perform a steer-by-wire function and / or a steering movement controlled by a driver assistance function. [5] Vehicle (500) with a steering device (100) according to any one of claims 1 to 4. [6] Method (300) for operating a steering device (100) according to any one of the preceding claims 1 to 4, wherein the method (300) comprises the following step: Controlling (305) a servo drive (115) to move the steering rod (110) using the rack and pinion structure (140). [7] Control unit (400) configured to perform and / or control the step (305) of the method (300) according to claim 6 in a corresponding unit (405). [8] Computer program configured to execute and / or control the method (300) according to claim 6. [9] Machine-readable storage medium on which the computer program according to claim 8 is stored.

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