Steering system and method of manufacturing a plurality of steering systems

Abstract

The invention relates to a steering system and to a method for manufacturing a plurality of steering systems, which steering system consists of steering system components, including at least one electric motor and a steering gear device, wherein the steering gear device has a first steering gear input shaft, which can be coupled to a steering shaft, and a second steering gear input shaft, which is drivably coupled to the electric motor, and also has a steering gear output shaft and a steering gear device housing, which has a fixing element for fixing the steering gear device housing to a superordinate structure, in particular to a vehicle body. The steering system is characterized in that the steering gear device housing is designed in such a way that, with each of these housings, a steering system can be produced which, in terms of the arrangement and orientation of the first and second steering gear input shafts, the steering gear output shaft and the fixing element, is mirror-symmetrical to the steering system with respect to a mirror plane, in particular a vertical mirror plane.

Description

Technical Field

[0001] The present invention relates to a steering system comprising steering system components, including at least one electric motor and a steering gear device, wherein the steering gear device has a first steering gear input shaft coupled to a steering shaft and a second steering gear input shaft drivably coupled to the electric motor, the steering gear device also having a steering gear output shaft and a steering gear device housing having a fixing element for fixing the steering gear device housing to a higher-level structure, particularly a vehicle body.

[0002] The present invention also relates to a method for manufacturing multiple steering systems. Background Technology

[0003] DE202014101670U1 discloses a power steering system. This power steering system has a steering wheel shaft on which a first worm and a worm wheel are coaxially arranged. The power steering system also has a power assist shaft on which a second worm is coaxially arranged, meshing with the worm wheel. The power steering system further has a segmented shaft with a gear segment that meshes with the first worm.

[0004] DE102019127965A1 discloses a steering gear for an electromechanical steering system in a vehicle. The steering gear includes an input shaft coupled to or to a steering column of the steering system, a segmented shaft coupled to or to a steering arm of the steering system, an angle gear mechanism, a servo gear mechanism, and an electric motor for driving the servo gear mechanism. The angle gear mechanism is designed as a bevel gear mechanism. The input shaft and the electric motor are connected to the servo gear mechanism. The servo gear mechanism is connected to the angle gear mechanism. The angle gear mechanism is connected to the segmented shaft. The angle gear mechanism is configured to transmit torque from the servo gear mechanism to the segmented shaft via two transmission paths.

[0005] DE10234596B3 discloses a power steering system for non-rail vehicles, which is designed as a recirculating ball steering system. To improve the variability of the recirculating ball steering system, a servo motor is arranged at the steering input end. This servo motor is designed as an electric motor to reduce the steering effort.

[0006] DE102015217045A1 discloses a commercial vehicle steering system comprising a steering gear for transmitting manual torque applied to a steering wheel to a steering arm. The steering gear has an electric motor for providing auxiliary torque for assisted steering, wherein the steering assistance is provided entirely electrically throughout the entire operating range of the steering system. The steering gear also has an input shaft and an output shaft, the rotation axes of which are intersected. The steering gear further has a first gear assembly coupling the input shaft and the output shaft, and a second gear assembly with the electric motor connected to the input side of the second gear assembly. The second gear assembly is coupled to the output side of the output shaft, and the reduction gear stage of the second gear assembly is arranged coaxially with the output shaft. Summary of the Invention

[0007] The problem the invention aims to solve

[0008] Therefore, the object of the present invention is to provide a steering system of the type described above, which can be configured in a simple manner as a steering system for right-hand drive vehicles and a steering system for left-hand drive vehicles.

[0009] Solution for solving the problem

[0010] This objective is achieved by a steering system characterized in that the steering gear housing is designed such that, with respect to the arrangement and orientation of the first and second steering gear input shafts, the steering gear output shaft, and the fixed elements, a steering system can be manufactured that is mirror-symmetrical to the steering system with respect to the mirror surface, particularly the vertical mirror surface.

[0011] The steering system according to the present invention enables a mirror-symmetric steering system to be implemented in a simple manner using the same parts, thereby simplifying adaptation to different vehicle variants, particularly left-hand drive and right-hand drive vehicles, without the need for complex redesign. This results in higher production efficiency, reducing both development and manufacturing costs.

[0012] For example, the fixing element of the steering gear housing can be designed as a through hole or a threaded hole for fixing screws.

[0013] In one specific embodiment, the torque path from the first steering input shaft to the steering output shaft has at least two drivably connected gear stages in series. In particular, at least one of the gear stages can advantageously be designed as a strain wave gear mechanism, a cycloidal gear mechanism, an RV reduction mechanism, or a bevel gear mechanism. Furthermore, at least one of the gear stages can advantageously be designed as a worm gear mechanism, a spindle gear mechanism, or a staggered-axis helical gear mechanism.

[0014] A staggered-axis helical gear mechanism shall be understood as a gear mechanism having two helical gears that are in a state of directly meshing with each other, and whose rotation axes are staggered from each other. In particular, the rotation axis of one gear may lie in a plane whose surface normal is parallel to the rotation axis of the other gear. It may be advantageously provided that the following applies to both helical gears: L<Dπsinβ, where L is the axial length of the gear, D is the root diameter of the helical tooth portion, π is the mathematical constant, and β is the helix angle.

[0015] An RV reduction mechanism shall be understood as a transmission system comprising a cycloidal gear mechanism and a preceding gear stage. Said cycloidal gear mechanism comprises at least one cycloidal disk having a cycloidal external tooth portion meshing with circumferentially arranged roller pins. The motion of said cycloidal disk is generated by a plurality of eccentric shafts, which are arranged eccentrically and each is mounted in a state rotatable about its own axis. Each eccentric shaft carries a gear having external teeth meshing with a centrally arranged drive gear. The gears of said eccentric shafts and said drive gear are components of said preceding gear stage. Said drive gear transmits its rotational motion to said gears of said eccentric shafts, whereby said eccentric shafts drive said cycloidal disk to perform a wobbling motion, in which said cycloidal disk rolls circumferentially along the circumference of said roller pins.

[0016] In a particularly advantageous embodiment, all steering system components are designed in such a way that with these components, a steering system mirror-symmetrical to said steering system with respect to a mirror surface, in particular a vertical mirror surface, can be manufactured at least in terms of the arrangement and orientation of said first and second steering gear input shafts, said steering gear output shaft and said fixed element. A particular advantage of this embodiment is that identical parts can be used. Since all steering system components are designed such that they can be used in a mirror-symmetrical manner, the requirement for different parts for right-hand drive vehicles and left-hand drive vehicles is eliminated. This reduces the number of variants, which in turn allows both production costs and logistics costs to be significantly reduced. By using identical parts, economies of scale can also be utilized in the manufacturing process, thereby reducing production costs. Assembly is also simplified because the same components can be used regardless of installation orientation. At the same time, the maintainability of the product is also improved, since the variety of stock parts required for spare parts supply is reduced.

[0017] Optionally, in one embodiment, the steering system components, including worms, spindles, and / or helical gears, which are designed as components of a gear stage such as a worm gear mechanism, a spindle gear mechanism, or an alternating-axis helical gear mechanism, can be designed in such a way that when all worms, spindles, and helical gears are replaced by identical components having opposite helical directions, a steering system can be manufactured that is mirror-symmetrical to the steering system with respect to a mirror surface, particularly a vertical mirror surface, at least in terms of the arrangement and orientation of the first and second steering input shafts, the steering output shaft, and the fixed elements. This embodiment also has the significant advantage of using identical parts.

[0018] Whether it is necessary to replace the worm, spindle, and helical gear with the same gears having opposite helical directions depends on the configuration of the rest of the steering system and the connection scheme between the steering system and the other steering components in right-hand drive and left-hand drive vehicles.

[0019] In a particularly advantageous embodiment, the first gear stage is designed as a bevel gear mechanism, worm gear mechanism, main shaft gear mechanism, crossed-axis helical gear mechanism, or strain wave gear mechanism, while the second gear stage, drivably connected downstream of the first gear stage, is designed as a cycloidal gear mechanism, RV reduction mechanism, or strain wave gear mechanism. Combining different types of gears in two consecutive gear stages brings several decisive advantages to the steering system. One major advantage is that the desired gear ratio can be achieved through a very compact structural design. This implementation allows for integration into the vehicle while ensuring space savings, which is particularly advantageous for commercial vehicles with limited installation space. Furthermore, the mechanical coupling interface of the steering system can be optimized in arrangement and orientation, thereby simplifying and saving space during system installation in the vehicle. This implementation facilitates system integration into different vehicle platforms.

[0020] In an advantageous embodiment of the steering system, the electric motor is coupled to the second steering gear input shaft via a transmission device. This allows the motor's speed and torque to be adjusted according to the requirements of the steering system.

[0021] In a particularly advantageous embodiment, the transmission device is designed as a traction drive mechanism or a mechanism incorporating a traction drive mechanism. Traction drive mechanisms, such as synchronous belt drives or chain drives, enable low-noise, low-vibration power transmission. Furthermore, the traction drive mechanism allows the electric motor to be positioned relative to the steering gear device in a manner particularly advantageous for utilizing available installation space in the vehicle.

[0022] Alternatively, the transmission device can also be designed as a spur gear mechanism, or include a spur gear mechanism. To achieve a favorable transmission ratio with a compact design, it may be advantageous for the spur gear mechanism to include three spur gears.

[0023] Another advantageous embodiment specifies that the transmission device is designed as a strain wave gear mechanism or a mechanism incorporating a strain wave gear mechanism. The strain wave gear mechanism also allows for an extremely compact structural design, and, due to its backlash-free power transmission, it can provide exceptionally high steering accuracy.

[0024] In particular, the steering system can, for example, through the advantageous embodiments of the transmission device described above, be designed such that the motor is offset from, and particularly offset parallel to, the second gear stage and / or the steering gear output shaft. This arrangement achieves a space-saving design and allows for flexible integration of the motor into the vehicle's mounting space.

[0025] Optionally, the steering system can be designed such that the motor is coaxially arranged with the second gear stage. This design ensures direct and low-loss power transmission, thereby improving system efficiency. Furthermore, it results in a particularly compact unit with a radial structure, simplifying installation and maintenance.

[0026] The steering gear housing can advantageously employ a multi-part design. This multi-part design simplifies assembly. Furthermore, the multi-part design of the steering gear housing facilitates maintenance as the enclosed steering system components are more easily accessible.

[0027] In a particularly advantageous embodiment, the steering gear housing at least accommodates the drivably connected gear stages in series. This protects the steering system components of the gear stages from external influences such as dust, moisture, or mechanical loads, thereby contributing to improved service life and reliability of the steering system.

[0028] Furthermore, the steering gear housing can also accommodate the transmission device. This ensures optimal protection against contamination and mechanical impacts.

[0029] A particularly advantageous embodiment specifies that the steering gear housing, especially at the opening in its housing wall, includes at least one input shaft bearing housing for a steering input shaft bearing. A steering input shaft bearing for rotatably supporting the steering input shaft can be arranged in the input shaft bearing housing. This allows the steering input shaft to be stably supported. The steering input shaft bearing can advantageously be designed as a rolling bearing, particularly a ball bearing, roller bearing, or angular contact roller bearing.

[0030] In a particularly advantageous embodiment, in addition to the input shaft bearing housing, the steering gear housing also includes another input shaft bearing housing, which is arranged mirror-symmetrically with respect to a horizontal mirror surface to the first input shaft bearing housing. A steering input shaft bearing for supporting the steering input shaft can be arranged in this input shaft bearing housing. This symmetrical design facilitates manufacturing and enables cost-effective variations for both left-hand drive and right-hand drive vehicles in terms of the slewing bearing of the steering input shaft.

[0031] In particular, it can be advantageously specified that, depending on whether the steering system is to be manufactured for a right-hand drive vehicle or a left-hand drive vehicle, the steering input shaft bearing is embedded in either the input shaft bearing housing or the other input shaft bearing housing. Preferably, when the steering input shaft bearing is embedded in the input shaft bearing housing, the other input shaft bearing housing is closed with a cover. Conversely, when the steering input shaft bearing is embedded in the other input shaft bearing housing, the input shaft bearing housing is preferably closed with a cover. The cover is preferably designed to be removable in a non-destructive manner for, for example, maintenance.

[0032] Optionally, it can be advantageously specified that a steering input shaft bearing is embedded in both the input shaft bearing housing and the other input shaft bearing housing to securely and rotatably support the first steering input shaft. Then, depending on whether the steering system is intended for a right-hand drive vehicle or a left-hand drive vehicle, the steering input shaft extends from the steering unit housing through the opening in either the input shaft bearing housing or the other input shaft bearing housing. The opening in the corresponding other input shaft bearing housing is preferably closed with a cover.

[0033] The steering gear housing may advantageously include an output shaft bearing housing for a steering output shaft bearing, thereby achieving precise rotational support for the steering output shaft. A steering output shaft bearing may be arranged within the output shaft bearing housing.

[0034] In a particularly advantageous embodiment, in addition to the output shaft bearing housing, the steering gear housing also includes another output shaft bearing housing, which is arranged symmetrically with respect to a mirror surface with respect to the first output shaft bearing housing. A steering output shaft bearing for supporting the steering output shaft can be arranged in the output shaft bearing housing. This symmetrical design facilitates manufacturing and enables cost-effective variations for both left-hand drive and right-hand drive vehicles in terms of the slewing bearing of the steering output shaft.

[0035] In particular, it can be advantageously specified that, depending on whether the steering system is to be manufactured for a right-hand drive vehicle or a left-hand drive vehicle, the steering output shaft bearing is embedded in either the output shaft bearing housing or the other output shaft bearing housing. Preferably, when the steering output shaft bearing is embedded in the output shaft bearing housing, the other output shaft bearing housing is closed with a cover. Conversely, when the steering output shaft bearing is embedded in the other output shaft bearing housing, the output shaft bearing housing is preferably closed with a cover. The cover is preferably designed to be removable in a non-destructive manner for, for example, maintenance.

[0036] In a particularly advantageous embodiment, the distance between the plane of rotation axis perpendicular to the steering output shaft and on which the first steering input shaft is arranged, and the plane on which the portion of the steering device housing directly surrounds the output shaft bearing housing is arranged, is between 70 mm and 90 mm, or equal to 80 mm. These dimensions achieve a good balance between compactness, structural stability, and utilization of available installation space.

[0037] The steering system can be advantageously designed such that the rotation axes of the first steering input shaft and the steering output shaft are staggered. This arrangement allows for particularly efficient use of installation space and enables integration within the vehicle. In particular, the rotation axes of the first steering input shaft and the steering output shaft can also be arranged in mutually perpendicular planes, further maximizing installation space utilization and facilitating vehicle integration. In a particularly advantageous embodiment, the distance between the rotation axes of the first steering input shaft and the steering output shaft is 80 mm to 100 mm, especially 90 mm.

[0038] A particularly advantageous steering arrangement includes a steering system according to the invention and a steering shaft operatively connected to a steering handle, wherein the steering shaft is coupled to the first steering input shaft, preferably directly coupled, or integrally manufactured with the first steering input shaft.

[0039] A particularly advantageous vehicle, especially a commercial vehicle, particularly a truck or bus, incorporates a steering system according to the invention or a steering arrangement according to the invention.

[0040] According to a particularly advantageous method of manufacturing multiple steering systems, the present invention first provides steering system components. These steering system components particularly include multiple identical electric motors, multiple steering devices, and multiple steering device housings. Each steering device includes a first steering input shaft coupled to a steering shaft and a second steering input shaft coupled to or coupled to the electric motor in a drivable manner, and a steering output shaft. Each steering device housing has a fixing element for securing the steering device housing to a higher-level structure, particularly a vehicle body. The steering device housings are designed such that, with each of these housings, a steering system can be manufactured that is mirror-symmetrical to the steering system with respect to a mirror surface, particularly a vertical mirror surface, in terms of the arrangement and orientation of the first and second steering input shafts, the steering output shaft, and the fixing element. According to the present invention, the steering device housings are designed such that they can be used to manufacture steering systems for both right-hand drive and left-hand drive vehicles.

[0041] In a particularly advantageous embodiment, the steering system for left-hand drive vehicles and the steering system for right-hand drive vehicles are assembled entirely from the same steering system components. This significantly reduces the number of parts, thereby achieving cost savings in production and logistics. Component standardization also simplifies inventory management and reduces assembly complexity.

[0042] In another advantageous embodiment, the steering system for a left-hand drive vehicle and the steering system for a right-hand drive vehicle can also consist of components that are identical except for the use of worms, spindles, or helical gears with opposite helical directions.

[0043] As described above, it can be advantageously specified that, depending on whether the steering system is manufactured for a right-hand drive vehicle or a left-hand drive vehicle, the steering input shaft bearing for rotating support of the steering input shaft is embedded in an input shaft bearing housing, or in another input shaft bearing housing arranged in a mirror-symmetric manner with the input shaft bearing housing.

[0044] As described above, it can be advantageously specified that, depending on whether the steering system is manufactured for a right-hand drive vehicle or a left-hand drive vehicle, the steering output shaft bearing for rotating support of the steering output shaft is embedded in an output shaft bearing housing, or in another output shaft bearing housing arranged in a mirror-symmetric manner with the output shaft bearing housing. Attached Figure Description

[0045] In the accompanying drawings, the subject matter of the invention is illustrated by way of example. The following description refers to the figures, wherein, even in different embodiments, elements that are the same or functionally identical are generally given the same reference numerals. The figures are as follows:

[0046] Figure 1 This is a cross-sectional view of a first embodiment of the steering system according to the present invention;

[0047] Figure 2 This is another cross-sectional view of a first embodiment of the steering system according to the present invention;

[0048] Figure 3 This is a side view of a first embodiment of the steering system according to the present invention;

[0049] Figure 4 This is a perspective view of a first embodiment of the steering system according to the present invention;

[0050] Figure 5 A frontal perspective view of a first embodiment of a steering system according to the present invention is shown, as well as another frontal perspective view of a steering system that is mirror-symmetrical to the above-described steering system with respect to a mirror, particularly a vertical mirror.

[0051] Figure 6 A rear-view perspective view of a first embodiment of a steering system according to the present invention is shown, as well as another rear-view perspective view of a steering system that is mirror-symmetrical to the above-described steering system with respect to a mirror, particularly a vertical mirror.

[0052] Figure 7 shows a side view of a first embodiment of the steering system according to the present invention, and another side view of a steering system that is mirror-symmetrical to the above-described steering system with respect to a mirror, particularly a vertical mirror.

[0053] Figure 8 This is a detailed schematic diagram of the staggered shaft helical gear mechanism and RV reduction mechanism according to a first embodiment of the steering system of the present invention;

[0054] Figure 9 This is a cross-sectional view of a second embodiment of the steering system according to the present invention;

[0055] Figure 10 This is another cross-sectional view of a second embodiment of the steering system according to the present invention;

[0056] Figure 11 This is a side view of a second embodiment of the steering system according to the present invention;

[0057] Figure 12 This is a perspective view of a second embodiment of the steering system according to the present invention;

[0058] Figure 13 A front perspective view of a second embodiment of the steering system according to the present invention is shown, as well as another front perspective view of a steering system that is mirror-symmetrical to the above-described steering system with respect to a mirror, particularly a vertical mirror.

[0059] Figure 14 A rear-view perspective view of a second embodiment of the steering system according to the present invention is shown, as well as another rear-view perspective view of a steering system that is mirror-symmetrical to the above-described steering system with respect to a mirror, particularly a vertical mirror.

[0060] Figure 15 A side view of a second embodiment of the steering system according to the invention is shown, as well as another side view of a steering system that is mirror-symmetrical to the above-described steering system with respect to a mirror, particularly a vertical mirror.

[0061] Figure 16 This is a detailed schematic diagram of the worm gear mechanism and RV reduction mechanism according to a second embodiment of the steering system of the present invention;

[0062] Figure 17 This is a detailed schematic diagram of one embodiment of the combination of an interleaved shaft helical gear mechanism and an RV reduction mechanism used in the steering system according to the present invention;

[0063] Figure 18 This is a detailed schematic diagram of another embodiment of the combination of the staggered-axis helical gear mechanism and the RV reduction mechanism in the mirror-symmetric steering system according to the present invention, wherein the mirror-symmetric steering system is, at least in terms of the arrangement and orientation of the first and second steering input shafts, the steering output shaft, and the fixed elements, similar to that according to the present invention... Figure 17 The design combination targets a steering system that is mirror-symmetrical.

[0064] Figure 19 This is a cross-sectional view of a third embodiment of the steering system according to the present invention;

[0065] Figure 20 This is another cross-sectional view of a third embodiment of the steering system according to the present invention;

[0066] Figure 21 This is a side view of a third embodiment of the steering system according to the present invention;

[0067] Figure 22 A front perspective view of a third embodiment of a steering system according to the present invention is shown, as well as another front perspective view of a steering system that is mirror-symmetrical to the above-described steering system with respect to a mirror, particularly a vertical mirror.

[0068] Figure 23A rear-view perspective view of a third embodiment of the steering system according to the invention is shown, as well as another rear-view perspective view of a steering system mirror-symmetrical to the aforementioned steering system with respect to a mirror surface, particularly a vertical mirror surface; and

[0069] Figure 24 A side view of a first embodiment of a steering system according to the invention is shown, as well as another side view of a steering system that is mirror-symmetrical to the above-described steering system with respect to a mirror, particularly a vertical mirror. Detailed Implementation

[0070] Figure 1 A cross-sectional view of a first embodiment of the steering system 1 according to the present invention is shown.

[0071] The steering system 1 comprises steering system components, including an electric motor 2 and a steering gear assembly 3. The steering gear assembly 3 has a first steering input shaft 4 coupled to a steering axis (not shown) and a second steering input shaft 5 drivably coupled to the electric motor 2. The steering gear assembly 3 also has a steering output shaft 6. The steering system components further include a steering gear housing 7 with multiple fixing elements 8 for securing the steering gear housing 7 to a higher-level structure, particularly the vehicle body. The fixing elements 8 of the steering gear housing 7 can be designed as, for example, through holes or threaded holes 9 for fixing screws.

[0072] like Figures 5 to 7 As shown, the steering gear housing 7 is designed in such a way that a steering system 11 can be manufactured from this housing. This steering system 11 is mirror-symmetrical to the steering system 1 with respect to the mirror surface 10, particularly a vertical mirror surface, at least in terms of the arrangement and orientation of the first steering input shaft 4, the second steering input shaft 5, the steering output shaft 6, and the fixing element 8. Specifically, in this embodiment, the steering system components are designed such that when the helical gears 17 and 18 of the staggered-axis helical gear mechanism 19 housed in the steering gear housing 7 are replaced by identical helical gears having opposite helical directions, a steering system 11 can be manufactured from these steering system components. This steering system 11 is mirror-symmetrical to the steering system 1 with respect to the mirror surface 10 in terms of the arrangement and orientation of the first steering input shaft 4, the second steering input shaft 5, the steering output shaft 6, and the fixing element 8.

[0073] Motor 2 is coupled to the second steering input shaft 5 via a transmission device 12. The transmission device 12 is designed as a spur gear mechanism, comprising a first spur gear 13 directly connected to the output shaft 14 of motor 2 in a non-rotatable manner. The transmission device 12 also includes a second spur gear 15 rotatably mounted, the teeth of which mesh with the teeth of the first spur gear 13. The transmission device 12 further includes a third spur gear 16 directly connected to the second steering input shaft 5 in a non-rotatable manner.

[0074] The torque path from the first steering input shaft 4 to the steering output shaft 6 comprises multiple drivably connected gear stages in series. The first gear stage is designed as a staggered-axis helical gear mechanism 19, while the second gear stage, drivably connected downstream of the first gear stage, is designed as an RV reduction mechanism 20.

[0075] The RV reduction mechanism 20 includes a cycloidal gear mechanism 21 and a preceding gear stage 22. The cycloidal gear mechanism 21 is drivably connected downstream of the motor 2 via a transmission device 12 and the preceding gear stage 22. The cycloidal gear mechanism 21 includes two cycloidal disks 23 and 24, each having cycloidal external teeth that mesh with circumferentially arranged roller pins 25. The movement of the cycloidal disks 23 and 24 is generated by a plurality of eccentric shafts 26, each eccentrically arranged, and each eccentric shaft 26 is mounted rotatably relative to the cycloidal disks 23 and 24 about its own axis via rolling bearings 27.

[0076] Each eccentric shaft 26 has one eccentric shaft gear 28 and another eccentric shaft gear 29. The eccentric shaft gear 28 and the other eccentric shaft gear 29 of each eccentric shaft 26 are arranged on opposite sides of the two cycloidal disks 23, 24.

[0077] Another eccentric shaft gear 29 is a component of the preceding gear stage 22. The centrally located second steering input shaft 5 has an external tooth portion 30 that meshes with the external teeth of the other eccentric shaft gear 29. Therefore, the second steering input shaft 5 acts as the drive gear 57 of the preceding gear stage 22, transmitting its rotational motion to the other eccentric shaft gear 29. This causes the eccentric shaft 26 to drive the cycloidal disks 23 and 24 in an oscillating motion, during which the cycloidal disks 23 and 24 roll circumferentially along the circumference of the roller pin 25. During this process, the eccentric shaft 26 rotates not only about its own axis but also, together with the cycloidal disks 23 and 24, about the central rotation axis 31 of the RV reduction mechanism 20. Each eccentric shaft 26 is coupled to the steering output shaft 6 via its respective other rolling bearing 32, thus transmitting the rotational motion of the cycloidal disks 23 and 24 about the central rotation axis 31 to the steering output shaft 6 via the eccentric shaft 26.

[0078] Furthermore, each eccentric shaft 26 is drivably coupled to the first steering input shaft 4 via an interleaved helical gear mechanism 19. The interleaved helical gear mechanism 19 includes a first helical gear 17 arranged coaxially with the steering input shaft 4 and indirectly connected to it in a non-rotatable manner. The interleaved helical gear mechanism 19 also includes a second helical gear 18, the outer helical teeth of which mesh with the outer helical teeth of the first helical gear 17. The rotation axes of the helical gears 17 and 18 are arranged interleaved relative to each other, wherein the second helical gear 18 rotates about the central rotation axis 31 of the cycloidal gear mechanism 21.

[0079] The second helical gear 18 is designed as a ring, with an outer circumference having an outer helical tooth portion that meshes with the outer helical tooth portion of the first helical gear 17. Along its inner circumference, the second helical gear 18 has an inner tooth portion 54 that meshes with the outer tooth portion 55 of another eccentric shaft gear 29. The second helical gear 18 is rotatably mounted relative to the steering gear output shaft 6 via a plurality of rolling bearings 33.

[0080] Therefore, the torque path from the first steering input shaft 4 to the steering output shaft 6 comprises multiple drivably connected gear stages in series. One of these gear stages is formed by an alternating-axis helical gear mechanism 19. Another of these gear stages is formed by the meshing of the internal tooth portion 54, preferably spur teeth, of a second helical gear 18 with the external tooth portion 55 of an eccentric shaft gear 28. Yet another of these gear stages is formed by a cycloidal gear mechanism 21. The helical gear 18 forms an intermediate gear 56, which is a component of the two drivably connected gear stages in series.

[0081] The steering gear housing 7 has an output shaft bearing seat 34 in which a steering gear output shaft bearing 35 and a seal 53 are arranged. The steering gear output shaft bearing 35 is used to rotatably support the steering gear output shaft 6.

[0082] The distance 36 between the plane 37, which is perpendicular to the steering output shaft 6 and on which the rotation axis of the first steering input shaft 4 is arranged, and the plane 38, which is arranged on the outer side of the steering device housing 7 directly surrounding the output shaft bearing seat 34, is between 70 mm and 90 mm, preferably 80 mm.

[0083] The rotation axes of the first steering input shaft 4 and the steering output shaft 6 are arranged in a plane perpendicular to each other, with a distance of 80 mm to 100 mm, particularly 90 mm, between the two axes.

[0084] Figure 2 Another cross-sectional view of a first embodiment of the steering system 1 according to the present invention is shown.

[0085] from Figure 2 As can be seen, the steering input shaft 4 includes an input portion 40 designed as a solid shaft, an intermediate portion 41 designed as a solid shaft, and a hollow shaft portion 42, in which a first helical gear 17 is formed in a portion.

[0086] The intermediate portion 41 is directly connected to the input portion 40 at one end in a non-rotatable manner, and directly connected to the hollow shaft portion 42 at the other end in a non-rotatable manner, wherein the hollow shaft portion 42 surrounds a portion of the intermediate portion 41 and the input portion 40.

[0087] The steering system 1 includes a first rotation angle sensor 43 that detects the rotational position and speed of the input portion 40 of the first steering input shaft 4. The steering system 1 also includes a second rotation angle sensor 44 that detects the rotational position of the hollow shaft portion 42 surrounding the input portion 40 of the first steering input shaft 4. The first rotation angle sensor 43 includes a first rotation angle sensor element 60 and a first encoding element 61, which, for example, takes the form of an encoding disk, a gear ring, or a magnetic wheel, and engages with the first rotation angle sensor element 60 in a non-contact manner. The second rotation angle sensor 44 includes a second rotation angle sensor element 62 and a second encoding element 63, which, for example, takes the form of an encoding disk, a gear ring, or a magnetic wheel, and engages with the second rotation angle sensor element 62 in a non-contact manner. The first rotation angle sensor element 60 and the second rotation angle sensor element 62 can advantageously be arranged together on the same carrier and / or in the same sensor housing. In the figure, the first rotation angle sensor element 60 and the second rotation angle sensor element 62 are represented by a single closed polygon with a diagonal line.

[0088] Measurement signals from the first rotation angle sensor element 60 and the second rotation angle sensor element 62 are transmitted to a control device (not shown), which takes the measurement signals into account to control the motor 2. In this case, the control device can infer the torque currently applied to the first steering gear input shaft 4 via the steering handle (not shown) based on the corresponding difference between the rotation angle detected by the first rotation angle sensor element 60 and the rotation angle detected by the second rotation angle sensor element 62. This is feasible because: the input portion 40, where the first encoding element 61 is arranged, and the end of the hollow shaft portion 42, where the second encoding element 63 is arranged, which is directly connected to the intermediate portion 41, both belong to the first steering gear input shaft 4, but in terms of torque path, they are located upstream and downstream of the first helical gear 17 of the interleaved shaft helical gear mechanism 19, respectively. Therefore, when torque is applied, they rotate relative to each other due to torsion, especially the torsion of the relatively thin intermediate portion 41, wherein the difference in rotation angle increases with the increase of the torque applied to the first steering gear input shaft 4 via the steering handle.

[0089] It can be advantageously specified that the control device controls the motor 2 based at least on the rotation angle difference between the first rotation angle sensor element 60 and the second rotation angle sensor element 62.

[0090] The steering gear housing 7 includes an input shaft bearing seat 45 and another input shaft bearing seat 46, which is arranged mirror-symmetrically with respect to a horizontal mirror surface to the first input shaft bearing seat. An input shaft bearing module 47 is disposed within the input shaft bearing seat 45 and includes a first rolling bearing 58 and a second rolling bearing 59. The input portion 40 is rotatably supported by the first rolling bearing 58. The end of the hollow shaft portion 42 surrounding the input portion 40 is rotatably supported by the second rolling bearing 59.

[0091] Another input shaft bearing module 48 is arranged in another input shaft bearing housing 46, which includes a rolling bearing 64. The end of the hollow shaft portion 42, which is directly connected to the intermediate portion 41, is rotatably supported by the rolling bearing 64.

[0092] Input shaft bearing module 47 and another input shaft bearing module 48 are specifically designed to reliably rotate and support the first steering input shaft 4, wherein the first rotation angle sensor element 60 and the second rotation angle sensor element 62 are spatially integrated in the input shaft bearing module 47. The first steering input shaft 4 extends outward through an opening in the input shaft bearing housing 45.

[0093] However, if it is necessary to manufacture a mirror-symmetric steering system 11 for right-hand drive vehicles, rather than a steering system 1 that might be designed for left-hand drive vehicles, then the steering gear housing 7 can be as follows: Figures 5 to 7 As shown, it is used in the following manner: the first steering input shaft 4 extends outward from the steering device housing 7 through the opening of the other input shaft bearing seat 46.

[0094] Figure 3 A side view of steering system 1 is shown. Figure 4 A perspective view of the steering system 1 is shown. As can be seen from these two figures, there are a total of five fixing elements 8, which can be designed as threaded holes.

[0095] There are two upper fixing elements 49, two lower fixing elements 50, and one intermediate fixing element 51. The fixing elements 8 are arranged in a mirror image symmetrical about the plane 52 on which the central axis of rotation 31 and the intermediate fixing element 51 are arranged.

[0096] like Figures 5 to 7 As shown, the steering gear housing 7 is designed such that a steering system 11 can be manufactured from this housing. This steering system 11 is mirror-symmetrical to the steering system 1 in terms of the arrangement and orientation of the first steering input shaft 4, the second steering input shaft 5, the steering output shaft 6, and the fixing elements 8, with respect to the mirror surface 10, particularly the vertical mirror surface. In the steering system 1, two upper fixing elements 49 are arranged at the top, while in the mirror-symmetrical steering system 11, two upper fixing elements 49 are arranged at the bottom. In the steering system 1, two lower fixing elements 50 are arranged at the bottom, while in the mirror-symmetrical steering system 11, two lower fixing elements 50 are arranged at the top.

[0097] In steering system 1, the steering input shaft 4 extends outward through the opening of the input shaft bearing housing 45, while in mirror-symmetric steering system 11, the steering input shaft 4 extends outward through the opening of another input shaft bearing housing 46.

[0098] Figure 8 This is a detailed schematic diagram of the staggered shaft helical gear mechanism 19 and RV reduction mechanism 20 according to a first embodiment of the steering system of the present invention; wherein, for clarity, the helical teeth of the first helical gear 17 and the second helical gear 18 are not shown.

[0099] Figure 9 A cross-sectional view of a second embodiment of the steering system 1 according to the present invention is shown.

[0100] The steering system 1 comprises steering system components, including at least one electric motor 2 and a steering gear assembly 3. The steering gear assembly 3 has a first steering input shaft 4 coupled to a steering axis (not shown) and a second steering input shaft 5 drivably coupled to the electric motor 2. The steering gear assembly 3 also has a steering output shaft 6. The steering system components further include a steering gear housing 7 with multiple fixing elements 8 for securing the steering gear housing 7 to a higher-level structure, particularly the vehicle body. The fixing elements 8 of the steering gear housing 7 can be designed as, for example, through holes or threaded holes 9 for fixing screws.

[0101] The steering gear housing 7 is designed such that a steering system 11 can be manufactured from this housing. This steering system 11, at least in terms of the arrangement and orientation of the first steering input shaft 4, the second steering input shaft 5, the steering output shaft 6, and the fixing element 8, is mirror-symmetrical to the steering system 1 with respect to the mirror 10, particularly the vertical mirror. The steering system 11 is shown in… Figures 13 to 15 The following will describe it in more detail. Specifically, in this embodiment, the steering system components are designed as follows: the worm gear mechanism 67 housed in the steering gear housing 7 includes a worm wheel 66 in addition to the worm shaft 65. When the worm shaft 65 of the worm gear mechanism 67 is replaced by the same worm shaft with the opposite helical direction, a steering system 11 can be manufactured using these steering system components. This steering system 11 is mirror-symmetrical to the steering system 1 about the mirror surface 10 in terms of the arrangement and orientation of the first steering input shaft 4, the second steering input shaft 5, the steering output shaft 6, and the fixing element 8.

[0102] Motor 2 is coupled to the second steering input shaft 5 via a transmission device 12. The transmission device 12 is designed as a spur gear mechanism, comprising a first spur gear 13 directly connected to the output shaft 14 of motor 2 in a non-rotatable manner. The transmission device 12 also includes a second spur gear 15 rotatably mounted, the teeth of which mesh with the teeth of the first spur gear 13. The transmission device 12 further includes a third spur gear 16 directly connected to the second steering input shaft 5 in a non-rotatable manner.

[0103] The torque path from the first steering input shaft 4 to the steering output shaft 6 comprises multiple drivably connected gear stages in series. The first gear stage is designed as a staggered-axis helical gear mechanism 19, while the second gear stage, drivably connected downstream of the first gear stage, is designed as an RV reduction mechanism 20.

[0104] The RV reduction mechanism 20 includes a cycloidal gear mechanism 21 and a preceding gear stage 22. The cycloidal gear mechanism 21 is drivably connected downstream of the motor 2 via a transmission device 12 and the preceding gear stage 22. The cycloidal gear mechanism 21 includes two cycloidal disks 23 and 24, each having cycloidal external teeth that mesh with circumferentially arranged roller pins 25. The movement of the cycloidal disks 23 and 24 is generated by a plurality of eccentric shafts 26, each eccentrically arranged, and each eccentric shaft 26 is mounted rotatably relative to the cycloidal disks 23 and 24 about its own axis via rolling bearings 27.

[0105] Each eccentric shaft 26 has an eccentric shaft gear 28 and another eccentric shaft gear 29. The eccentric shaft gear 28 and the other eccentric shaft gear 29 of each eccentric shaft 26 are respectively arranged on different sides of the two cycloidal disks 23 and 24.

[0106] Another eccentric shaft gear 29 is part of the preceding gear stage 22. A centrally located second steering input shaft 5 has an external tooth portion 30 that meshes with the external teeth of the other eccentric shaft gear 29. Therefore, the second steering input shaft 5 acts as the drive gear 57 of the preceding gear stage 22, transmitting its rotational motion to the other eccentric shaft gear 29. This causes the eccentric shaft 26 to drive the cycloidal disks 23 and 24 in an oscillating motion, during which the cycloidal disks 23 and 24 roll circumferentially along the circumference of the roller pin 25. In addition to rotating around its own axis, the eccentric shaft 26 also rotates together with the cycloidal disks 23 and 24 around the central rotation axis 31 of the RV reduction mechanism. Each eccentric shaft 26 is coupled to the steering output shaft 6 via its respective rolling bearing 32, so that the rotational motion of the cycloidal disks 23 and 24 around the central rotation axis 31 is transmitted to the steering output shaft via the eccentric shaft 26.

[0107] Furthermore, each eccentric shaft 26 is drivably coupled to the first steering input shaft 4 via a worm gear mechanism 67. As previously described, the worm gear mechanism 67 includes a worm shaft 65, which is coaxially arranged with the steering input shaft 4 and indirectly connected to it in a non-rotatable manner. The worm gear mechanism 67 also includes a worm wheel 66, the external teeth of which are engaged with the worm shaft 65. The axes of rotation of the worm shaft 65 and the worm wheel 66 are arranged alternately relative to each other, wherein the worm wheel 66 rotates about the central axis of rotation 31 of the cycloidal gear mechanism 21.

[0108] The worm gear 66 has a ring-shaped design, as previously described, with external teeth on its outer circumference that mesh with the worm shaft 65. Along its inner circumference, the worm gear 66 has internal teeth 54 that mesh with the external teeth 55 of another eccentric shaft gear 29. The worm gear 66 is rotatably mounted relative to the steering gear output shaft 6 via a plurality of rolling bearings 33.

[0109] Therefore, the torque path from the first steering input shaft 4 to the steering output shaft 6 comprises multiple drivably connected gear stages in series. One of these gear stages is formed by a worm gear mechanism 67. Another of these gear stages is formed by the meshing of the preferably spur internal tooth portion 54 of a worm wheel 66 with the external tooth portion 55 of an eccentric shaft gear 28. Yet another of these gear stages is formed by a cycloidal gear mechanism 21. The worm wheel 66 forms an intermediate gear 56, which is a component of the two drivably connected gear stages in series.

[0110] The steering unit housing 7 includes an output shaft bearing housing 34, in which a steering output shaft bearing 35 and a seal 53 are arranged, wherein the steering output shaft bearing 35 is used to rotatably support the steering output shaft 6.

[0111] The distance 36 between the plane 37, which is perpendicular to the steering output shaft 6 and on which the rotation axis of the first steering input shaft 4 is arranged, and the plane 38, which is arranged on the outer side of the steering device housing 7 directly surrounding the output shaft bearing seat 34, is between 70 mm and 90 mm, preferably equal to 80 mm.

[0112] The rotation axes of the first steering input shaft 4 and the steering output shaft 6 are arranged in mutually perpendicular planes, with a spacing of 80 mm to 100 mm, particularly 90 mm, between the two axes.

[0113] Figure 10 Another cross-sectional view of a second embodiment of the steering system 1 according to the present invention is shown.

[0114] from Figure 10 As can be seen, the steering input shaft 4 includes an input portion 40 designed as a solid shaft, an intermediate portion 41 designed as a solid shaft, and a hollow shaft portion 42, in which a first helical gear 17 is formed in a portion.

[0115] The intermediate portion 41 is directly connected to the input portion 40 at one end in a non-rotatable manner, and directly connected to the hollow shaft portion 42 at the other end in a non-rotatable manner, wherein the hollow shaft portion 42 surrounds a portion of the intermediate portion 41 and the input portion 40.

[0116] The steering system 1 has a first rotation angle sensor 43 that detects the rotational position and speed of the input portion 40 of the first steering input shaft 4. The steering system 1 also has a second rotation angle sensor 44 that detects the rotational position of the hollow shaft portion 42 surrounding the input portion 40 of the first steering input shaft 4. The first rotation angle sensor 43 includes a first rotation angle sensor element 60 and a first encoding element 61, which takes the form of, for example, an encoding disk, a gear ring, or a magnetic wheel, and engages with the first sensor element 60 in a non-contact manner. The second rotation angle sensor 44 includes a second rotation angle sensor element 62 and a second encoding element 63, which takes the form of, for example, an encoding disk, a gear ring, or a magnetic wheel, and engages with the second rotation angle sensor element 62 in a non-contact manner. The first rotation angle sensor element 60 and the second rotation angle sensor element 62 can advantageously be arranged together on the same carrier and / or in the same sensor housing. In the figure, the first rotation angle sensor element 60 and the second rotation angle sensor element 62 are represented by a single closed polygon with a diagonal line.

[0117] Measurement signals from the first rotation angle sensor element 60 and the second rotation angle sensor element 62 are transmitted to a control device (not shown) that takes these signals into account when controlling the motor 2. In this case, the control device can infer the torque currently applied to the first steering gear input shaft 4 via the steering handle (not shown) based on the corresponding difference between the rotation angles of the first and second rotation angle sensor elements 60 and 62. This is feasible because the input portion 40, where the first encoding element 61 is arranged, and the end of the hollow shaft portion 42, where the second encoding element 63 is arranged, directly connected to the intermediate portion 41, both belong to the first steering gear input shaft 4, but are located upstream and downstream of the worm wheel 66 of the worm gear mechanism 67, respectively, in terms of torque path. Therefore, when torque is applied due to torsion, particularly the torsion of the relatively thin intermediate portion 41, they will rotate relative to each other, with the difference in rotation angle increasing as the torque applied to the first steering gear input shaft 4 via the steering handle increases.

[0118] It can be advantageously specified that the control device controls the motor 2 based at least on the rotation angle difference between the first rotation angle sensor element 60 and the second rotation angle sensor element 62.

[0119] The steering gear housing 7 includes an input shaft bearing seat 45 and another input shaft bearing seat 46, which is arranged mirror-symmetrically with respect to a horizontal mirror surface to the first input shaft bearing seat. An input shaft bearing module 47 is disposed within the input shaft bearing seat 45 and includes a first rolling bearing 58 and a second rolling bearing 59. The input portion 40 is rotatably supported by the first rolling bearing 58. The end of the hollow shaft portion 42 surrounding the input portion 40 is rotatably supported by the second rolling bearing 59.

[0120] Another input shaft bearing module 48 is arranged in another input shaft bearing housing 46, which includes a rolling bearing 64. The end of the hollow shaft portion 42, which is directly connected to the intermediate portion 41, is rotatably supported by the rolling bearing 64.

[0121] Input shaft bearing module 47 and another input shaft bearing module 48 are specifically designed to reliably rotatably support the first steering input shaft 4, wherein the first rotation angle sensor element 60 and the second rotation angle sensor element 62 are spatially integrated in the steering input shaft bearing module 47. The steering input shaft 4 extends outward through an opening in the input shaft bearing housing 45.

[0122] However, if it is necessary to manufacture a mirror-symmetric steering system 11 for right-hand drive vehicles, rather than a steering system 1 that might be designed for left-hand drive vehicles, then the steering gear housing 7 can be as follows: Figures 13 to 15 As shown, the steering input shaft 4 extends outward from the steering unit housing 7 through the opening of another input shaft bearing seat 46.

[0123] Figure 11 A side view of steering system 1 is shown. Figure 12 A perspective view of the steering system 1 is shown. As can be seen from these two figures, there are a total of five fixing elements 8, which can be designed as threaded holes.

[0124] There are two upper fixing elements 49, two lower fixing elements 50, and one intermediate fixing element 51. The fixing elements 8 are arranged in a mirror image symmetrical about the plane 52 on which the central axis of rotation 31 and the intermediate fixing element 51 are arranged.

[0125] like Figures 13 to 15As shown, the steering gear housing 7 is designed such that a steering system 11 can be manufactured from this housing. This steering system 11 is mirror-symmetrical to the steering system 1 in terms of the arrangement and orientation of the first steering input shaft 4, the second steering input shaft 5, the steering output shaft 6, and the fixing elements 8, with respect to the mirror surface 10, particularly the vertical mirror surface. In the steering system 1, two upper fixing elements 49 are arranged at the top, while in the mirror-symmetrical steering system 11, two upper fixing elements 49 are arranged at the bottom. In the steering system 1, two lower fixing elements 50 are arranged at the bottom, while in the mirror-symmetrical steering system 11, two lower fixing elements 50 are arranged at the top.

[0126] In steering system 1, the steering input shaft 4 extends outward through the opening of the input shaft bearing housing 45, while in mirror-symmetric steering system 11, the steering input shaft 4 extends outward through the opening of another input shaft bearing housing 46.

[0127] Figure 16 A detailed schematic diagram of the worm gear mechanism 67 and RV reduction mechanism 20 according to a second embodiment of the steering system of the present invention is shown; wherein, for clarity, the external teeth of the worm gear 66 and the threads of the worm shaft 65 are not shown.

[0128] Figure 17 A detailed schematic diagram of one embodiment of a combination of an interleaved shaft helical gear mechanism 19 and an RV reduction mechanism 20 for use in a steering system according to the present invention is shown.

[0129] and Figure 8 The combination of the staggered shaft helical gear mechanism 19 and the RV reduction mechanism 20 shown is different, with the eccentric shaft gear 28 and another eccentric shaft gear of each eccentric shaft arranged on the same side of the two cycloidal disks 23, 24.

[0130] Figure 18 A detailed schematic diagram of another embodiment of the combination of the staggered-axis helical gear mechanism 19 and the RV reduction mechanism 20 for the mirror-symmetric steering system 11 according to the present invention is shown, wherein the mirror-symmetric steering system 11 is, at least in terms of the arrangement and orientation of the first steering input shaft 4 and the second steering input shaft 5, the steering output shaft 6, and the fixing element 8, similar to that according to the present invention... Figure 17 The design combination targets a steering system 1 that is mirror-symmetric.

[0131] Figure 18 The combination of the staggered shaft helical gear mechanism 19 and the RV reduction mechanism 20 shown is... Figure 17The combination of the staggered helical gear mechanism 19 and the RV reduction mechanism 20 shown is made of the same parts and is mirror symmetrical. However, the first helical gear 17 is replaced by a first helical gear 68 that is otherwise identical but has the opposite helical direction, and the second helical gear 18 is replaced by a second helical gear 69 that is otherwise identical but has the opposite helical direction.

[0132] For example, Figure 17 The implementation shown can be used in left-hand drive vehicles, while Figure 18 The illustrated mirror-symmetric implementation can be used for right-hand drive vehicles. However, depending on the configuration of the remaining steering components of the steering system and the connection scheme between the steering system and the remaining steering components in the vehicle, it is entirely possible to use [other methods] for right-hand drive vehicles. Figure 18 The illustrated combination of the staggered-axis helical gear mechanism 19 and the RV reduction mechanism 20 eliminates the need to replace helical gears 17 and 18 with helical gears 68 and 69 that have opposite helical directions but are otherwise identical. This mirror-symmetric combination can be used with... Figure 17 The same steering system components are used in the implementation shown.

[0133] Figure 19 A cross-sectional view of a third embodiment of the steering system 1 according to the present invention is shown.

[0134] The steering system 1 comprises steering system components, including an electric motor 2 and a steering gear assembly 3. The steering gear assembly 3 has a first steering input shaft 4 coupled to a steering axis (not shown) and a second steering input shaft 5 drivably coupled to the electric motor 2. The steering gear assembly 3 also has a steering output shaft 6. The steering system components further include a steering gear housing 7 with multiple fixing elements 8 for securing the steering gear housing 7 to a higher-level structure, particularly the vehicle body. The fixing elements 8 of the steering gear housing 7 can be designed as, for example, through holes or threaded holes 9 for fixing screws.

[0135] The steering gear housing 7 is designed such that a steering system 11 can be manufactured from this housing. This steering system 11, at least in terms of the arrangement and orientation of the first steering input shaft 4, the second steering input shaft 5, the steering output shaft 6, and the fixing element 8, is mirror-symmetrical to the steering system 1 with respect to the mirror 10, particularly the vertical mirror. The steering system 11 is shown in… Figures 22 to 24The following will describe it in more detail. Specifically, in this embodiment, the steering system components are designed in such a way that a steering system 11 can be manufactured that is mirror-symmetrical to the steering system 1 about the mirror surface 10 in terms of the arrangement and orientation of the first steering input shaft 4, the second steering input shaft 5, the steering output shaft 6, and the fixing element 8.

[0136] In the torque path from motor 2 to steering gear output shaft 6, steering gear unit 3 includes a strain wave gear mechanism 70 and another strain wave gear mechanism 71, which are drivably connected in series.

[0137] Motor 2 is coupled to the second steering input shaft 5 via transmission device 12. Transmission device 12 is designed as a traction drive, comprising a traction means 72, a first traction means carrier 73, and a second traction means carrier 74. The first traction means carrier 73 is directly connected to the output shaft 75 of motor 2 in a non-rotatable manner. The second traction means carrier 74 is connected to the second steering input shaft 5 in a non-rotatable manner.

[0138] The second steering input shaft 5 is designed as a hollow shaft and has an elliptical portion 76, which serves as a deformable part of the wave generator 80 of the strain wave gear mechanism 70. This deformable part is supported in a rotatable state by a radial flexible rolling bearing 77. The elliptical portion 76 presses the end of a cup-shaped flexible wheel 78 with external teeth into an elliptical shape and engages with the internal teeth of a rigid wheel 79 in two meshing positions. Together with the radial flexible rolling bearing 77, the elliptical portion 76 constitutes the wave generator 80 of the strain wave gear mechanism 70.

[0139] The outer circumference of the rigid wheel 79 of the strain wave gear mechanism 70 is elliptical, thus it can simultaneously serve as a deformable form of another wave generator of another strain wave gear mechanism 71. This deformable form is supported in a rotatable state by another radial flexible rolling bearing 81. The rigid wheel 79 presses the end of another cup-shaped flexible wheel 82 with external teeth into an elliptical shape, and engages with the internal teeth of another rigid wheel 83 in two meshing positions. This other rigid wheel 83 is arranged in a non-rotatable manner relative to the steering gear housing 7. The other cup-shaped flexible wheel 82 acts as the output end of another strain wave gear mechanism 71, and is connected to the steering gear output shaft 6 in a non-rotatable manner.

[0140] The torque path from the first steering input shaft 4 to the steering output shaft 6 comprises multiple drivably connected gear stages in series. The first gear stage is designed as a bevel gear mechanism 90 having a crown gear 91 and a pinion 92. The crown gear 91 is non-rotatably connected to the steering input shaft 4. The pinion 92 is non-rotatably connected to a bell-shaped external spur gear 94 via a rotatably mounted shaft 93, the teeth of which mesh with the teeth of another rotatably mounted spur gear 95. Spur gear 94 and the other spur gear 95 constitute another stage in the gear series. The other spur gear 95 is non-rotatably connected to a rigid wheel 79.

[0141] The steering unit housing 7 includes an output shaft bearing housing 34, in which a steering output shaft bearing 35 and a seal 53 are arranged, wherein the steering output shaft bearing 35 is used to rotatably support the steering output shaft 6.

[0142] Figure 20 Another cross-sectional view of a third embodiment of the steering system 1 according to the present invention is shown.

[0143] from Figure 20 As can be seen, the steering input shaft 4 includes an input portion 40 designed as a solid shaft, an intermediate portion 41 designed as a solid shaft, and a hollow shaft portion 42. The intermediate portion 41 is directly connected to the input portion 40 at one end in a non-rotatable manner, and is directly connected to the hollow shaft portion 42 at the other end in a non-rotatable manner, wherein the hollow shaft portion 42 surrounds the intermediate portion 41.

[0144] The steering system 1 has a first rotation angle sensor 43 that detects the rotational position and speed of the input portion 40 of the first steering input shaft 4. The steering system 1 also has a second rotation angle sensor 44 that detects the rotational position of the hollow shaft portion 42 surrounding the input portion 40 of the first steering input shaft 4. The first rotation angle sensor 43 includes a first rotation angle sensor element 60 and a first encoding element 61, which takes the form of, for example, an encoding disk, a gear ring, or a magnetic wheel, and engages with the first sensor element 60 in a non-contact manner. The second rotation angle sensor 44 includes a second rotation angle sensor element 62 and a second encoding element 63, which takes the form of, for example, an encoding disk, a gear ring, or a magnetic wheel, and engages with the second rotation angle sensor element 62 in a non-contact manner. The first rotation angle sensor element 60 and the second rotation angle sensor element 62 can advantageously be arranged together on the same carrier and / or in the same sensor housing. In the figure, the first rotation angle sensor element 60 and the second rotation angle sensor element 62 are represented by a single closed polygon with a diagonal line.

[0145] Measurement signals from the first rotation angle sensor element 60 and the second rotation angle sensor element 62 are transmitted to a control device (not shown) that takes these signals into account when controlling the motor 2. In this case, the control device can infer the torque currently applied to the first steering gear input shaft 4 via the steering handle (not shown) based on the corresponding difference between the rotation angles of the first and second rotation angle sensor elements 60 and 62. This is feasible because the input portion 40, where the first encoding element 61 is arranged, and the end of the hollow shaft portion 42, where the second encoding element 63 is arranged, directly connected to the intermediate portion 41, both belong to the first steering gear input shaft 4, but are located upstream and downstream of the worm wheel 66 of the worm gear mechanism 67, respectively, in terms of torque path. Therefore, when torque is applied due to torsion, particularly the torsion of the relatively thin intermediate portion 41, they will rotate relative to each other, with the difference in rotation angle increasing as the torque applied to the first steering gear input shaft 4 via the steering handle increases.

[0146] It can be advantageously specified that the control device controls the motor 2 based at least on the rotation angle difference between the first rotation angle sensor element 60 and the second rotation angle sensor element 62.

[0147] The steering gear housing 7 includes an input shaft bearing seat 45 and another input shaft bearing seat 46, wherein the other input shaft bearing seat 46 is arranged mirror-symmetrically with respect to a horizontal mirror surface to the input shaft bearing seat 45. An input shaft bearing module 47 is disposed within the input shaft bearing seat 45 and includes a rolling bearing 96. The input section 40 is rotatably supported by the rolling bearing 96.

[0148] Another input shaft bearing module 48 is arranged in another input shaft bearing housing 46, which contains two rolling bearings 97 for supporting the steering input shaft 4.

[0149] Input shaft bearing module 47 and another input shaft bearing module 48 are specifically designed to reliably rotate and support the first steering input shaft 4. The steering input shaft 4 extends outward through an opening in the input shaft bearing housing 45.

[0150] However, if it is necessary to manufacture a mirror-symmetric steering system 11 for right-hand drive vehicles, rather than a steering system 1 that might be designed for left-hand drive vehicles, then the steering gear housing 7 can be as follows: Figures 22 to 24 As shown, the steering input shaft 4 extends outward from the steering unit housing 7 through the opening of another input shaft bearing seat 46.

[0151] Figure 21 A side view of the steering system 1 is shown. It can be seen that there are a total of five fixing elements 8, which can be designed as threaded holes.

[0152] There are two upper fixing elements 49, two lower fixing elements 50, and one intermediate fixing element 51. The fixing elements 8 are arranged in a mirror image symmetrical about the plane 52 on which the central axis of rotation 31 and the intermediate fixing element 51 are arranged.

[0153] like Figures 22 to 24 As shown, the steering gear housing 7 is designed such that a steering system 11 can be manufactured from this housing. This steering system 11 is mirror-symmetrical to the steering system 1 in terms of the arrangement and orientation of the first steering input shaft 4, the second steering input shaft 5, the steering output shaft 6, and the fixing elements 8, with respect to the mirror surface 10, particularly the vertical mirror surface. In the steering system 1, two upper fixing elements 49 are arranged at the top, while in the mirror-symmetrical steering system 11, two upper fixing elements 49 are arranged at the bottom. In the steering system 1, two lower fixing elements 50 are arranged at the bottom, while in the mirror-symmetrical steering system 11, two lower fixing elements 50 are arranged at the top.

[0154] In steering system 1, the steering input shaft 4 extends outward through the opening of the input shaft bearing housing 45, while in mirror-symmetric steering system 11, the steering input shaft 4 extends outward through the opening of another input shaft bearing housing 46.

[0155] Explanation of reference numerals in the attached figures:

[0156] 1. Steering system

[0157] 2. Motor

[0158] 3. Steering Gear

[0159] 4. First steering gear input shaft

[0160] 5. Second steering gear input shaft

[0161] 6. Steering gear output shaft

[0162] 7. Steering gear housing

[0163] 8. Fixing components

[0164] 9. Threaded hole

[0165] 10. Mirror

[0166] 11. Mirror-symmetric steering system

[0167] 12. Transmission device

[0168] 13. First spur gear

[0169] 14. Output shaft

[0170] 15. Second spur gear

[0171] 16. Third spur gear

[0172] 17. First helical gear

[0173] 18. Second helical gear

[0174] 19. Crossed-axis helical gear mechanism

[0175] 20. RV reduction gear

[0176] 21. Cycloidal gear mechanism

[0177] 22. Previous gear stage

[0178] 23. Cycloidal disc

[0179] 24. Cycloidal disc

[0180] 25. Roller pins

[0181] 26. Eccentric shaft

[0182] 27. Rolling bearings

[0183] 28. Eccentric shaft gear

[0184] 29. Another eccentric shaft gear

[0185] 30. External teeth

[0186] 31. Central axis of rotation

[0187] 32. Another rolling bearing

[0188] 33. Rolling bearings

[0189] 34. Output shaft bearing housing

[0190] 35. Steering gear output shaft bearing

[0191] 36. Distance

[0192] 37. Plane

[0193] 38. Plane

[0194] 39. Distance

[0195] 40. Input Section

[0196] 41. Middle section

[0197] 42. Hollow shaft section

[0198] 43. First rotation angle sensor

[0199] 44. Second rotation angle sensor

[0200] 45. Input shaft bearing housing

[0201] 46. ​​Another input shaft bearing housing

[0202] 47. Steering gear input shaft bearing module

[0203] 48. Another steering gear input shaft bearing module

[0204] 49. Upper fixing element

[0205] 50. Lower fixing element

[0206] 51. Central fixing element

[0207] 52. Plane

[0208] 53. Sealing components

[0209] 54. Internal teeth

[0210] 55. External teeth

[0211] 56. Intermediate gear

[0212] 57. Drive gear

[0213] 58. First rolling bearing

[0214] 59. Second rolling bearing

[0215] 60. First rotation angle sensor

[0216] 61. Second rotation angle sensor

[0217] 62. First coding element

[0218] 63. Second coding element

[0219] 64. Rolling bearings

[0220] 65. Worm shaft

[0221] 66. Worm Gear

[0222] 67. Worm gear mechanism

[0223] 68. The first helical gear with opposite helical directions

[0224] 69. The second helical gear with opposite helical directions

[0225] 70. Strain-wave gear mechanism

[0226] 71. Another strain wave gear mechanism

[0227] 72. Traction mechanism

[0228] 73. First traction mechanism bearing component

[0229] 74. Second traction mechanism bearing component

[0230] 75. Output shaft

[0231] 76. Elliptical section

[0232] 77. Radial Flexible Rolling Bearing

[0233] 78. Flexible wheel

[0234] 79. Rigid wheel

[0235] 80. Wave Generator

[0236] 81. Another radial flexible rolling bearing

[0237] 82. Another flexible wheel

[0238] 83. Another rigid wheel

[0239] 84. Bevel gear mechanism

[0240] 85. Crown Gear

[0241] 86. Small gear

[0242] 87. Shaft

[0243] 88. Spur gear

[0244] 89. Another spur gear

[0245] 90. Bevel gear mechanism

[0246] 91. Crown Gear

[0247] 92. Small gear

[0248] 93. Shaft

[0249] 94. Spur gears

[0250] 95. Another spur gear

[0251] 96. Rolling bearings

[0252] 97. Rolling bearings

Claims

1. A steering system comprising steering system components, including at least: Electric motor; A steering device having a first steering input shaft that can be coupled to a steering shaft and a second steering input shaft that can be drivenly coupled to the electric motor, and a steering output shaft; and A steering gear housing having a fixing element for securing the steering gear housing to a higher-level structure, particularly the vehicle body. Its features are: The design of the steering device housing allows for the manufacture of a steering system that is mirror-symmetrical to the steering system, at least in terms of the arrangement and orientation of the first steering input shaft, the second steering input shaft, the steering output shaft, and the fixed elements, with respect to the mirror surface, particularly the vertical mirror surface.

2. The steering system according to claim 1, characterized in that, a. The torque path from the first steering input shaft to the steering output shaft comprises at least two cascaded, drivably connected gear stages; or b. The torque path from the first steering input shaft to the steering output shaft includes at least two drivably connected gear stages connected in series, wherein at least one gear stage is designed as a strain wave gear mechanism, a cycloidal gear mechanism, an RV reduction mechanism, or a bevel gear mechanism.

3. The steering system according to claim 1 or 2, characterized in that, The design of the steering system components enables the manufacture of a steering system that is mirror-symmetrical to the steering system, at least in terms of the arrangement and orientation of the first steering input shaft, the second steering input shaft, the steering output shaft, and the fixed elements, with respect to the mirror surface, particularly the vertical mirror surface.

4. The steering system according to claim 2, characterized in that, At least one gear stage is designed as a worm gear mechanism, a spindle gear mechanism, or an alternating-axis helical gear mechanism, wherein the steering system components are designed such that, when all worms, spindles, and helical gears are replaced by identical worms, spindles, and helical gears having opposite helical directions, a steering system can be manufactured with these components that is mirror-symmetrical to the steering system at least in terms of the arrangement and orientation of the first steering input shaft, the second steering input shaft, the steering output shaft, and the fixed elements with respect to mirror surfaces, particularly vertical mirror surfaces.

5. The steering system according to any one of claims 2 to 4, characterized in that, a. The first gear stage is designed as a bevel gear mechanism, worm gear mechanism, spindle gear mechanism, staggered-axis helical gear mechanism, or strain wave gear mechanism, and a second gear stage drivably connected downstream of the first gear stage is designed as a cycloidal gear mechanism, RV reduction mechanism, or strain wave gear mechanism, and / or b. The electric motor is coupled to the input shaft of the second steering gear via a transmission device, wherein the transmission device is specifically designed as a traction transmission mechanism, a spur gear mechanism, or a strain wave gear mechanism, or includes a traction transmission mechanism, a spur gear mechanism, or a strain wave gear mechanism.

6. The steering system according to claim 5, characterized in that: The motor a. Offset from the second gear stage and / or the steering gear output shaft, particularly offset parallel to its axis, or, b. Arranged coaxially with the second gear stage.

7. The steering system according to any one of claims 1 to 6, characterized in that, The steering gear housing has at least one of the following features a to c: a. The steering gear housing adopts a multi-component design; b. The steering gear housing at least accommodates the gear stages that are drivably connected in series; c. The steering gear housing houses the transmission device.

8. The steering system according to any one of claims 1 to 7, characterized in that: a. The steering gear housing, particularly at the opening in its housing wall, includes at least one input shaft bearing housing for the steering input shaft bearing, or b. The steering gear housing, particularly at an opening in its housing wall, includes at least one input shaft bearing housing for a steering input shaft bearing or an input shaft bearing housing with a steering input shaft bearing, wherein the steering gear housing, particularly at another opening in its housing wall, includes at least one other input shaft bearing housing for a steering input shaft bearing, the other input shaft bearing housing being designed and arranged to be mirror-symmetrical with respect to a mirror surface, particularly a horizontal mirror surface, to the input shaft bearing housing.

9. The steering system according to any one of claims 1 to 8, characterized in that, a. The steering gear housing, particularly at the opening in its housing wall, includes at least one output shaft bearing housing for the steering gear output shaft bearing, or b. The steering gear housing, particularly at the opening in its housing wall, includes at least one output shaft bearing seat for a steering output shaft bearing. The distance between a plane perpendicular to the steering output shaft and arranging the rotation axis of the first steering input shaft, and a plane arranging the portion of the steering gear housing directly surrounding the output shaft bearing seat, is greater than 70 mm, particularly between 70 mm and 90 mm, especially equal to 80 mm, or c. The steering gear housing, particularly at an opening in its housing wall, includes at least one output shaft bearing seat for a steering gear output shaft bearing, wherein the steering gear housing, particularly at another opening in its housing wall, includes at least one other output shaft bearing seat for a steering gear output shaft bearing, the other output shaft bearing seat being designed and arranged to be mirror-symmetrical with respect to a mirror surface, particularly a horizontal mirror surface, or d. The steering gear housing, particularly at an opening in its housing wall, includes at least one output shaft bearing seat for a steering gear output shaft bearing, wherein the steering gear housing, particularly at another opening in its housing wall, includes at least one other output shaft bearing seat for a steering gear output shaft bearing, the other output shaft bearing seat being designed and arranged to be mirror-symmetrical with respect to a mirror surface, particularly a horizontal mirror surface, and wherein the distance between a plane perpendicular to the steering gear output shaft and on which the axis of rotation of the first steering gear input shaft is arranged and a plane arranged around the portion of the steering gear housing directly surrounding the other output shaft bearing seat is greater than 70 mm, particularly between 70 mm and 90 mm, particularly equal to 80 mm.

10. The steering system according to any one of claims 1 to 9, characterized in that, The steering system has at least one of the following characteristics a to c: a. The rotation axis of the first steering gear input shaft and the rotation axis of the steering gear output shaft intersect each other; b. The rotation axis of the first steering input shaft and the rotation axis of the steering output shaft are arranged in planes perpendicular to each other; c. The rotation axis of the first steering input shaft and the rotation axis of the steering output shaft are spaced 80 mm to 100 mm, particularly 90 mm apart.

11. A steering arrangement comprising a steering system according to any one of claims 1 to 10, and comprising a steering shaft operatively connected to a steering handle and coupled to the first steering input shaft.

12. A vehicle, particularly a commercial vehicle, especially a truck or bus, comprising a steering system according to any one of claims 1 to 10 or a steering arrangement according to claim 11.

13. A method for manufacturing a plurality of steering systems, particularly a method for manufacturing a steering system according to any one of claims 1 to 10, comprising the following steps: a. Providing a steering system component, the steering system component comprising: i. Multiple identical electric motors; ii. A plurality of steering devices, each of the steering devices having a first steering input shaft that can be coupled to a steering shaft and a second steering input shaft that is drivably coupled to or coupled to the electric motor, and a steering output shaft; as well as iii. A plurality of steering gear housings, each of the steering gear housings having a fixing element for securing the steering gear housing to a higher-level structure, particularly a vehicle body, wherein the steering gear housings are designed such that, with each of these housings, a steering system can be manufactured that is mirror-symmetrical to the steering system at least in terms of the arrangement and orientation of the first steering input shaft, the second steering input shaft, the steering output shaft, and the fixing element, with respect to the mirror surface, particularly the vertical mirror surface. b. Assemble the steering system components to obtain multiple steering systems for right-hand drive vehicles and multiple steering systems for left-hand drive vehicles.

14. The method according to claim 13, characterized in that: a. The steering system for the right-hand drive vehicle and the steering system for the left-hand drive vehicle are assembled from the same steering system components, particularly from entirely the same steering system components; or b. The steering system for the right-hand drive vehicle and the steering system for the left-hand drive vehicle are assembled from the same steering system components, except that: when the steering system components include a worm, a spindle, and / or a helical gear, the steering system for the left-hand drive vehicle and the steering system for the right-hand drive vehicle use the same worm, spindle, and helical gear having opposite helical directions.

15. The method according to claim 13 or 14, characterized in that, a. The steering gear housing, particularly at the openings in its housing walls, each includes an input shaft bearing housing for a steering input shaft bearing, and for the steering system of the left-hand drive vehicle, the steering input shaft bearing is embedded in the input shaft bearing housing; the steering gear housing, particularly at the openings in its housing walls, also includes another input shaft bearing housing for a steering input shaft bearing, and for the steering system of the right-hand drive vehicle, the steering input shaft bearing is embedded in the other input shaft bearing housing, and / or b. Each of the steering gear housings, particularly at the openings in its housing wall, includes an output shaft bearing housing for a steering gear output shaft bearing, and for the steering system of the left-hand drive vehicle, the steering gear output shaft bearing is embedded in the output shaft bearing housing. Each of the steering gear housings, particularly at the openings in its housing wall, also includes another output shaft bearing housing for a steering gear output shaft bearing, and for the steering system of the right-hand drive vehicle, the steering gear output shaft bearing is embedded in the other output shaft bearing housing.

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