Steering torque transmission assembly for a steering transmission

The steering torque module addresses the complexity and cost issues of existing assemblies by using a torsional rod with cylindrical fastening sections to form mutual fastening sections with steering components, resulting in a simpler, cleaner, and more cost-effective assembly process.

WO2025067776A1PCT designated stage expired Publication Date: 2025-04-03KNORR BREMSE SYSTEME FUER NUTZFAHIZEUGE GMBH
View PDF 3 Cites 0 Cited by

Patent Information

Application Number
PCT/EP2024/073513
Authority / Receiving Office
WO · WO
Patent Type
Applications
Current Assignee / Owner
Priority Date
2023-09-29
Filing Date
2024-08-21
Publication Date
2025-04-03

AI Technical Summary

Technical Problem

Existing steering torque transmission assemblies for vehicle steering gears, particularly in commercial vehicles, are complex and costly to assemble, with risks of contamination from chips and coolant during the manufacturing process.

Method used

A steering torque module comprising a torsional rod with cylindrical fastening sections and steering torque components, where the torsional rod forms mutual fastening sections with the steering components through pressing, reducing contamination and assembly time.

Benefits of technology

The solution simplifies the assembly process, reduces contamination risks, and lowers production costs while ensuring reliable torque transmission.

✦ Generated by Eureka AI based on patent content.

Smart Images

  • Figure EP2024073513_03042025_PF_FP_ABST
    Figure EP2024073513_03042025_PF_FP_ABST
Patent Text Reader

Abstract

The present invention relates to a steering torque transmission assembly (100) for a vehicle steering transmission, in particular a ball circuit spindle steering transmission for a commercial vehicle, comprising: - at least one torsion bar (102); - at least one first steering torque transmission component (104), in particular a steering shaft; and - at least one second steering torque transmission component (106), in particular a steering spindle, wherein the first steering torque transmission component (104) and the torsion bar (102) form, in the assembled state, at least one first mutually pressed-together fastening section (116), and / or wherein the second steering torque transmission component (106) and the torsion bar (102) form, in the assembled state, at least one second mutually pressed-together fastening section (118). The present invention also relates to a vehicle steering transmission for a vehicle, in particular a ball circuit spindle steering transmission for a commercial vehicle, comprising at least one above-mentioned steering torque transmission assembly. The present invention furthermore relates to a method for assembling at least one steering torque transmission assembly for a vehicle steering transmission, in particular a ball circuit spindle steering transmission for a commercial vehicle.
Need to check novelty before this filing date? Find Prior Art

Description

[0001] DESCRIPTION

[0002] Steering torque transmission assembly for a steering gear

[0003] The present invention relates to a steering torque transmission assembly for a vehicle steering gear, in particular for a recirculating ball screw steering gear for a commercial vehicle. Furthermore, the present invention relates to a steering gear for a vehicle, in particular a recirculating ball screw steering gear for a commercial vehicle, comprising at least one steering torque transmission assembly as described above. Furthermore, the present invention relates to a method for assembling at least one steering torque transmission assembly for a vehicle steering gear, in particular a recirculating ball screw steering gear for a commercial vehicle.

[0004] In the current state of the art, torsion bars (T-bars for short) are used in vehicle steering gears to connect the input shaft to the steering spindle. The torsion bar, or T-bar, serves to reset the input shaft and generate a specific torque during the deflection of the entire steering system. In the current state of the art, the torsion bar is connected to the input or steering shaft by a complex and expensive pin connection.

[0005] Such connection solutions between torsion bar and input shaft by means of pinning are already known from the state of the art.

[0006] In this regard, DE 10 2020 119281 A1 shows a shaft arrangement for a steering gear with an input shaft, with an output shaft and with a torsion bar, wherein the torsion bar is rotationally connected to the input shaft in an input-side connection region of the shaft arrangement, wherein the torsion bar is rotationally connected to the output shaft in an output-side connection region of the shaft arrangement.

[0007] However, this pinning process has several disadvantages during manufacturing. For example, chips can be introduced into the steering torque transmission assembly or the vehicle's steering gear, and the coolant required when drilling the pin hole also leads to contamination. Furthermore, pinning is quite time-consuming and therefore costly.

[0008] It is therefore the object of the present invention to further develop a steering torque transmission assembly of the type mentioned at the outset in an advantageous manner, in particular to the effect that this assembly is easier to assemble, more cost-effective to manufacture and safer to operate.

[0009] This object is achieved according to the invention by a steering torque transmission assembly having the features of claim 1. Accordingly, it is provided that a steering torque transmission assembly for a steering gear, in particular a ball screw steering gear for a commercial vehicle, is provided, which comprises the following:

[0010] - at least one torsion bar;

[0011] - at least one first steering torque transmission component, in particular a steering shaft; and

[0012] - at least one second steering torque transmission component, in particular a steering spindle, wherein the torsion bar has at least one first, in particular cylindrical, fastening section and at least one second, in particular cylindrical, fastening section, wherein the first steering torque transmission component has at least one first torsion bar fastening section, and wherein the second steering torque transmission component has at least one second torsion bar fastening section; wherein the first steering torque transmission component and the torsion bar, in the assembled state, form at least one first mutually pressed fastening section by means of the first fastening section and the first torsion bar fastening section, and / or wherein, in the assembled state, the second steering torque transmission component and the torsion bar, by means of the second fastening section and by means of the second torsion bar fastening section, form at least onesecond mutually pressed fastening section. The invention is based on the basic idea that the first steering torque transmission component and the torsion bar, in the assembled state, can form at least one first mutually pressed fastening section by means of the first fastening section and the first torsion bar fastening section. Additionally or alternatively, in the assembled state, the second steering torque transmission component and the torsion bar can form at least one second mutually pressed fastening section by means of the second fastening section and the second torsion bar fastening section. The first steering torque transmission component can be designed as a steering shaft. The second steering torque transmission component can correspondingly be designed as a steering spindle. The first fastening section can in particular be designed as a cylindrical fastening section. The second fastening sectioncan also be designed, in particular, as a cylindrical fastening section. By pressing the torsion bar with the first and / or second steering torque transmission component, production can be carried out with less contamination, so that the impurities or chips that arise during the production of the pin bore (as in the prior art) are avoided and are not introduced into the steering torque transmission assembly or the vehicle steering gear. Furthermore, the pressing process according to the invention is faster than pinning and less cost-intensive.

[0013] Furthermore, it can be provided that the first fastening section and the first torsion bar fastening section form an interference fit in the assembled state to form the first mutually pressed fastening section. Additionally or alternatively, the second fastening section and the second torsion bar fastening section can form an interference fit in the assembled state to form the second mutually pressed fastening section. By means of the respective interference fit, a defined compression can be realized between the respective fastening sections, which is suitable for transmitting the required steering torques. Since the design of component interfaces using so-called fits and, in this case, interference fits, has been standardized for decades, it is advantageous to rely on a uniform and reliable set of rules.This makes the product development process more reproducible, efficient, cost-effective and less error-prone.

[0014] Furthermore, it can be provided that the torsion bar is formed as solid material axially at least within the first fastening section. Additionally or alternatively, the torsion bar can be formed as solid material axially at least within the second fastening section. In this regard, solid material can be understood in particular to mean that no radial and / or axial recess, bore, groove, pocket, etc. is introduced within the two cylindrical fastening sections, which for example partially or continuously penetrates the cross-section of these fastening sections. In particular, the solid material can be understood in such a way that the torsion bar cannot have a bore for receiving a locking pin or locking bolt axially at least within the first and second cylindrical fastening sections. The omission of such a recess, bore, groove orThe pocket enlarges the effective cross-section of the torsion bar, increasing the polar section modulus while simultaneously reducing the notch effect. This allows, in particular, the mechanical load on the torsion bar to be reduced. Within the scope of this invention, the term "axial" refers to a direction that extends longitudinally or along a central axis of the steering torque transmission assembly. Similarly, within the scope of this invention, the term "radial" refers to a direction that extends perpendicularly from the central axis of the steering torque transmission assembly.

[0015] Furthermore, it can be provided that the torsion bar has at least a first end section and at least one second end section, which is arranged opposite the first end section, wherein the first fastening section is arranged on the first end section and wherein the second fastening section is arranged on the second end section. This arrangement of the fastening sections enables particularly simple assembly, since the torsion bar can be pushed or pressed into the steering shaft and into the steering spindle via the end sections. It is also conceivable for the first fastening section to have a toothed ring, at least in sections. Additionally or alternatively, it can be provided that the second fastening section also has a toothed ring, at least in sections. By means of the toothed ring or toothed rings, a toothed ring can be formed, particularly in the pressed state, in the region of the tooth edges and the first orsecond torsion bar fastening section of the steering shaft or steering spindle, an increased mutual surface pressure and / or edge pressure can occur, so that an even better pressing effect can be achieved.

[0016] Furthermore, it is possible for the first fastening section to have at least a first nominal external dimension and for the second fastening section to have at least a second nominal external dimension, wherein the first nominal external dimension and the second nominal external dimension are identical. Additionally or alternatively, the first nominal external dimension and the second nominal external dimension can be toleranced by means of an identical external tolerance dimension. The identical nominal external dimensions have the particular advantage of simplifying the manufacture of the first and second fastening sections.

[0017] Furthermore, it can be provided that the same external tolerance dimension has the same tolerance field position according to ISO standard ISO 286 in the range from j to zc. In particular, it can be provided that the same external tolerance dimension has the same tolerance field position in the range from p to zc according to ISO standard ISO 286. This tolerancing, in particular the tolerance field position in the range from p to zc, allows an interference fit of the torsion bar with the respective torsion bar fastening sections of the steering shaft and steering spindle that can be precisely defined with regard to the desired pressure. Additionally or alternatively, the same external tolerance dimension can have the same tolerance field size in the range from IT01 to IT18 according to ISO standard ISO 286. In other words, the same external tolerance dimension can be defined by a tolerance field position and tolerance field size according to the associated international standard ISO 286.The tolerance field position is defined using letters a to z from the alphabet (lowercase letters for shafts, bolts, or pins, and capital letters A to Z for corresponding bores). In other words, the tolerance field position defines a standardized dimensional distance of a tolerance field relative to the external nominal dimension (also called the zero line). The tolerance field size IT, as the name suggests, defines the size of a tolerance field itself, i.e., a permissible dimensional range within which the tolerance field may lie, regardless of the tolerance field position. The same external tolerance dimensions can have the particular advantage of simplifying the manufacture of the first and second fastening sections and improving the assembly of the torsion bar.

[0018] It is also conceivable for the first torsion bar fastening section to have at least a first nominal inner dimension and for the second torsion bar fastening section to have at least a second nominal inner dimension, wherein the first nominal inner dimension and the second nominal inner dimension are identical. Additionally or alternatively, the first nominal inner dimension and the second nominal inner dimension can be toleranced by means of an identical internal tolerance dimension. The identical nominal inner dimensions have the particular advantage of simplifying the manufacture of the first and second torsion bar fastening sections, since, for example, the same drilling tool can be used.

[0019] Furthermore, it is conceivable for the same internal tolerance dimension to have an H tolerance field in accordance with ISO standard ISO 286. Additionally or alternatively, the same internal tolerance dimension can have the same tolerance field size in the range from IT01 to IT18 in accordance with ISO standard ISO 286. This tolerancing, in particular the tolerance field position in the H tolerance field, allows an interference fit of the respective torsion bar fastening sections with the first and second fastening sections of the torsion bar, the tolerancing of which has already been explained, which can be precisely defined with regard to the desired compression. In other words, the same internal tolerance dimension can be defined in accordance with the associated international standard ISO 286 by a tolerance field position or

[0020] Tolerance field size can be defined, whereby the tolerance field position is defined with letters a to z (lower case letters for shafts, bolts or pins and capital letters A to Z for corresponding bores). In other words, the tolerance field position defines a standardized dimensional distance of a tolerance field relative to the outside nominal dimension (also called the zero line). The tolerance field size IT defines, as the name suggests, the size of a tolerance field, i.e. a permissible dimensional range within which the tolerance field may lie. The tolerancing of the respective outside tolerance dimensions and inside tolerance dimensions described above was defined with a view to the so-called standard bore. In other words, the tolerancing of the same inside tolerance dimension using the H tolerance field (according to ISO standard ISO 286) describes the standard bore system.In other words, the H tolerance zone of the bore defines a reference dimension, which is then referenced by means of corresponding tolerancing of the shaft, thus creating a desired fit. Consequently, in the standard bore system, the tolerance of the bore is always defined with an H tolerance zone and thus remains the same, while the corresponding shaft-bore fit is then selected and defined by selecting the tolerance zones for the shaft. It is equally conceivable that external and internal tolerance dimensions can be toleranced according to the standard shaft system. According to the standard shaft system, the external tolerance dimension of the torsion bar can be toleranced with an H zone, and the internal tolerance dimension of the steering spindle or steering shaft can, in particular, have a tolerance zone position in the range from P to ZC.

[0021] It is also possible for the first fastening section and the first torsion bar fastening section to form at least a first cylinder interference fit. In particular, a cylinder longitudinal interference fit can be formed. Additionally or alternatively, the second fastening section and the second torsion bar fastening section can also form at least a second cylinder interference fit. This cylinder interference fit can also be designed, in particular, as a cylinder longitudinal interference fit. A cylinder longitudinal interference fit is a mechanically simple shaft-hub connection and can be easily installed and, if necessary, removed again. With the correct fit selection (see above), the desired steering torque can be reliably transmitted over the entire service life of the assembly. Alternatively, it can also be provided that the first fastening section and the first torsion bar fastening section form at least a cylinder transverse interference fit.Alternatively, the second fastening section and the second torsion bar fastening section can also form at least one cylinder transverse compression joint.

[0022] Additionally, it can be provided that the first steering torque transmission component has at least one first blind hole in which the first torsion bar fastening section is arranged, and wherein the second steering torque transmission component has at least one second blind hole in which the second torsion bar fastening section is arranged. These configurations of the first and second steering torque transmission components primarily ensure a space-saving arrangement in the axial direction, since the torsion bar can be partially or completely accommodated in the axial direction by the two blind holes of the first and second steering torque transmission components.

[0023] Furthermore, it is conceivable that the first steering torque transmission component and / or the second steering torque transmission component and / or the torsion bar have at least one alignment element for the mutual alignment of the first and second steering torque transmission components. In particular, it can be provided that the first steering torque transmission component and the second steering torque transmission component have at least one alignment element for the mutual alignment of the first and second steering torque transmission components. In the event that the torsion bar forms a cylindrical interference fit with both the first and the second steering torque transmission component, a defined alignment of the central position of the first and second steering torque transmission components cannot be ensured. However, the first and second steering torque transmission components must be precisely aligned with one another, i.e.with as little angle of rotation as possible, in order to ensure the most precise torque and angle transmission possible.

[0024] Furthermore, the present invention relates to a steering gear for a vehicle, in particular a ball screw steering gear for a commercial vehicle, which comprises at least one steering torque transmission assembly as explained above.

[0025] All structural and functional features associated with the steering torque transmission assembly according to the invention described above, as well as its possible embodiments, can also be provided alone or in combination in the steering gear according to the invention, and the associated advantages can be achieved. Furthermore, the present invention relates to a method for assembling at least one steering torque transmission assembly for a steering gear, in particular a recirculating ball screw steering gear for a commercial vehicle, comprising the following steps:

[0026] - Providing at least one torsion bar;

[0027] - Providing at least one first steering torque transmission component, in particular a steering shaft;

[0028] - Providing at least one second steering torque transmission component, in particular a steering spindle;

[0029] - aligning the torsion bar and / or the first steering torque transmission component and / or the second steering torque transmission component with each other;

[0030] - pressing the torsion bar and the first steering torque transmission component by means of a first cylinder press fit; and

[0031] - Pressing the torsion bar and the second steering torque transmission component by means of a second cylinder press fit.

[0032] All structural and functional features associated with the steering torque transmission assembly according to the invention described above and its possible embodiments can also be provided alone or in combination in the method according to the invention for assembling the steering torque transmission assembly and the associated advantages can be achieved.

[0033] Further details and advantages of the invention will now be explained in more detail with reference to an embodiment shown in the drawings.

[0034] They show:

[0035] Fig. 1 is a schematic sectional view of an embodiment of a steering torque transmission assembly according to the invention;

[0036] Fig. 2 is a schematic representation of a torsion bar of the embodiment of the steering torque transmission assembly according to Fig. 1; Fig. 3 is a further schematic sectional representation of the embodiment of the steering torque transmission assembly according to Fig. 1; and

[0037] Fig. 4 is a flow chart illustrating the sequence of a method according to the invention for assembling the steering torque transmission assembly according to Fig. 1.

[0038] Fig. 1 shows a schematic sectional view of an embodiment of a steering torque transmission assembly 100 according to the invention.

[0039] The steering torque transmission assembly 100 is intended for a vehicle steering gear in the form of a recirculating ball screw steering gear for a commercial vehicle.

[0040] The steering torque transmission assembly 100 includes a torsion bar 102.

[0041] The torsion bar 102 has a first cylindrical attachment portion 108 and a second cylindrical attachment portion 110.

[0042] The cylindrical fastening sections 108, 110 are designed as circular cylindrical fastening sections, each with a radially outer fastening surface.

[0043] The torsion bar 102 further has a first end portion 120 and a second end portion 122 arranged opposite the first end portion 120.

[0044] According to Fig. 1 it can be seen that the first fastening section 108 is arranged at the first end section 120 and the second fastening section 110 is arranged at the second end section 122.

[0045] The torsion bar 102 is formed as solid material axially within the first fastening section 108 and axially within the second fastening section 110.

[0046] In this regard, solid material can be understood to mean that no radial and / or axial recess, bore, groove, or pocket is provided within the cylindrical fastening sections 108, 110, which, for example, penetrates the cross-section of these fastening sections, for example, continuously or partially.

[0047] In particular, the solid material is to be understood in such a way that the torsion bar 102 has no bore for receiving a locking pin or locking bolt axially at least within the first and second cylindrical fastening sections 108, 110.

[0048] The first fastening section 108 further has a first nominal outer dimension and the second fastening section 110 has a second nominal outer dimension.

[0049] The first nominal outside dimension and the second nominal outside dimension are equal. In other words, the first nominal outside dimension and the second nominal outside dimension represent the same dimensions.

[0050] In addition, the first nominal outside dimension and the second nominal outside dimension are each tolerated by means of an identical outside tolerance dimension.

[0051] The same external tolerance dimension has a tolerance field position in the range from p to zc.

[0052] In addition, the same external tolerance dimension has the same tolerance field size in the range from IT01 to IT18, preferably between IT5 and IT8, according to ISO standard ISO 286.

[0053] Between the two end sections 120, 122, the torsion bar 102 has a central section 136 through which the two end sections 120, 122 are connected to each other.

[0054] The torsion bar 102 is also formed as a solid material axially within the central section 136. The torsion bar 102 is designed as a one-piece component, ie, it has only a single integral torsion bar body, which is not composed of multiple body parts.

[0055] The steering torque transmission assembly 100 further comprises a first steering torque transmission component 104 in the form of a steering shaft 104.

[0056] The first steering torque transmission component or the steering shaft 104 further has a first torsion bar fastening section 112 for fastening the torsion bar 102.

[0057] Accordingly, the first steering torque transmission component 104 according to Fig. 1 has a first blind hole 132 in which the first torsion bar fastening section 112 is arranged.

[0058] The first blind hole 132 has a blind hole base region 138 in which the first torsion bar fastening section 112 is arranged.

[0059] As can be seen in Fig. 1, the first torsion bar fastening section 112 is introduced as a bore in the blind hole base area 138.

[0060] The first torsion bar attachment portion 112 further has a first nominal inner dimension.

[0061] Furthermore, the first steering torque transmission component or the steering shaft 104 has a first alignment element (not visible in Fig. 1).

[0062] The first alignment element can be designed in the form of an axial and / or radial projection or an axial and / or radial recess and / or as a marking.

[0063] The steering torque transmission assembly 100 also includes a second steering torque transmission component 106 in the form of a steering spindle 106. The second steering torque transmission component 106 or steering spindle 106 has a second torsion bar attachment portion 114 for attaching the torsion bar 102 therein.

[0064] The second steering torque transmission component 106 has a second blind hole 134 in which the second torsion bar fastening section 114 is arranged.

[0065] The second blind hole 134 has a blind hole base region 140 in which the second torsion bar fastening section 114 is arranged.

[0066] As can be seen in Fig. 1, the second torsion bar fastening section 114 is introduced as a bore in the blind hole base area 140.

[0067] The second torsion bar attachment portion 114 also has a second nominal inner dimension.

[0068] The first nominal inside dimension (as explained above) and the second nominal inside dimension are equal and are tolerated by means of an equal inside tolerance dimension.

[0069] The same internal tolerance dimension has an H tolerance field according to ISO standard ISO 286.

[0070] In addition, the same internal tolerance dimension has the same tolerance field size in the range from IT01 to IT18, preferably between IT5 and IT8, according to ISO standard ISO 286.

[0071] As can be further seen in Fig. 1, the first steering torque transmission component 104 or the steering shaft 104 and the torsion bar 102 in the assembled state form by means of the first fastening section 108 and the first torsion bar

[0072] Fastening portion 112 forms a first mutually pressed fastening portion 116. Consequently, the first fastening portion 108 and the first torsion bar fastening portion 112 form an interference fit in the assembled state to form the first mutually pressed fastening portion 116.

[0073] Consequently, the first fastening section 108 and the first torsion bar fastening section 112 form a first cylinder interference fit 128 in the form of a cylinder longitudinal interference fit.

[0074] The first cylinder interference fit 128 can alternatively be designed as a transverse interference fit or as an oil interference fit.

[0075] In addition, in the assembled state, the second steering torque transmission component 106 or the steering spindle 106 and the torsion bar 102 form a second mutually pressed fastening section 118 by means of the second fastening section 110 and by means of the second torsion bar fastening section 114.

[0076] The second fastening section 110 and the second torsion bar fastening section 114 accordingly form an interference fit in the assembled state to form the second mutually pressed fastening section 118.

[0077] Accordingly, the second fastening section 110 and the second torsion bar fastening section 114 form a second cylinder interference fit 130 in the form of a cylinder longitudinal interference fit.

[0078] The second cylinder interference fit 130 can alternatively be designed as a transverse interference fit or as an oil interference fit.

[0079] The second steering torque transmission component 106 or the steering spindle 106 further comprises a second alignment element (not visible in Fig. 1) for the mutual alignment of the first and second steering torque transmission components 104, 106. The second alignment element can be configured to correspond to the first alignment element and can have an axial and / or radial projection adapted to or corresponding to the first alignment element (e.g., if the first alignment element is configured as an axial and / or radial recess) or an axial and / or radial recess (if the first alignment element is configured as an axial and / or radial projection) and / or a marking aligned therewith.

[0080] As can be further seen in Fig. 1, the steering shaft 104, in the assembled state, is inserted into the second blind hole 134 of the steering spindle 106, so that the steering shaft 104 and the steering spindle 106 form a mutual axial overlap region 142 within the second blind hole 134.

[0081] Within the overlap area 142, the steering shaft 104 and the steering spindle 106 form a mutual toothing 144, which serves as an anti-twist device.

[0082] By means of the anti-twist device, the transmission of the steering torque from the steering shaft 104 to the torsion bar 102 is limited from a maximum angle of rotation of the torsion bar 102.

[0083] To form the mutual toothing 144, the steering shaft 104 has an external toothing 146 and the steering spindle 106 has an internal toothing 148, which overlap axially.

[0084] The anti-twist device is shown in more detail using the section plane AA spanned perpendicular to the central axis; please refer to Fig. 3 for details.

[0085] The torsion bar 102 has a guide section 150 in the second end section 122, which is guided in a corresponding torsion bar guide section 152. The corresponding torsion bar guide section 152 is introduced as a guide bore into an end section 154 of the steering shaft 104, which is arranged opposite the first blind hole base region 138.

[0086] The corresponding torsion bar guide section 152 and the guide section 150 of the torsion bar 102 form a clearance fit in the assembled state.

[0087] According to the invention, a steering gear for a vehicle in the form of a ball screw steering gear for a commercial vehicle (not shown in Fig. 1) is further provided, which comprises the steering torque transmission assembly 100 described above.

[0088] Fig. 2 shows a schematic representation of the torsion bar 102 of the steering torque transmission assembly 100 according to Fig. 1.

[0089] The torsion bar 102 has a first cylindrical attachment portion 108 and a second cylindrical attachment portion 110.

[0090] The cylindrical fastening sections 108, 110 are designed as circular cylindrical outer fastening sections according to Fig. 2.

[0091] The torsion bar 102 has a first end portion 120 and a second end portion 122 arranged opposite the first end portion 120.

[0092] According to Fig. 2 it can be seen that the first fastening section 108 is arranged at the first end section 120 and the second fastening section 110 is arranged at the second end section 122.

[0093] Between the two end sections 120, 122, the torsion bar 102 has a central section 136, through which the two end sections 120, 122 are connected to each other. The torsion bar 102 further has a circular-cylindrical guide section 150 in the second end section 122.

[0094] Axially inside the second end portion 122, between the guide portion 150 and the second fastening portion 110, it has a shoulder with a smaller diameter than the guide portion 150 and the second fastening portion 110.

[0095] As can be further seen from Fig. 2, the first fastening section 108 has at least in sections a toothed ring 124.

[0096] Accordingly, the second fastening section 110 also has a toothed ring 126 at least in sections.

[0097] Both gear rims 124, 126 are formed from external gear rims and each rise by means of their individual teeth from the circular cylindrical outer surface of the first and second fastening sections 108, 110.

[0098] Fig. 3 shows a further schematic sectional view of the embodiment of the steering torque transmission assembly 100 according to Fig. 1.

[0099] This schematic sectional view corresponds to the section plane AA according to Fig. 1 .

[0100] This shows the mutual toothing 144 formed by the steering shaft 104 and the steering spindle 106.

[0101] To form the mutual toothing 144, the steering shaft 104 has an external toothing 146 and the steering spindle 106 has an internal toothing 148.

[0102] A torsional angular clearance is provided between the adjacent teeth of the external toothing 146 and the internal toothing 148. When the steering shaft 104 is rotated, it transfers the steering torque to the torsion bar 102, which is torsionally elastic, so that adjacent teeth of the external toothing 146 and the internal toothing 148 move toward each other in the direction of rotation with increasing steering torque, i.e., increasing elastic torsional deformation of the torsion bar 102.

[0103] If the steering torque reaches a certain steering torque limit value, which corresponds to a limit torsional deformation of the torsion bar 102, adjacent tooth flanks of the teeth of the external toothing 146 and the internal toothing 148 touch each other, so that further elastic torsional deformation of the torsion bar 102 is prevented.

[0104] The steering torque which exceeds the specified steering torque limit is therefore transmitted via the mutual toothing 144.

[0105] Fig. 4 shows a flow chart for the sequence of a method according to the invention for assembling the steering torque transmission assembly according to Fig. 1.

[0106] The method for assembling the steering torque transmission assembly 100 for a vehicle steering gear in the form of a ball screw steering gear for a commercial vehicle comprises the following steps S1 to S6:

[0107] According to a first step S1, a torsion bar 102 is provided.

[0108] The torsion bar can be designed in particular according to Figs. 1 to 3.

[0109] According to a second step S2, a first steering torque transmission component 104 in the form of a steering shaft (as explained above in Figs. 1 and 3) is provided.

[0110] According to a third step S3, a second steering torque transmission component 106 in the form of a steering spindle 106 (as explained above in Figs. 1 and 3) is provided. According to a fourth step S4, the first steering torque transmission component 104 and the second steering torque transmission component 106 are aligned with each other.

[0111] According to a fifth step S5, the torsion bar 102 and the first steering torque transmission component 104 are pressed together by means of a first cylinder press fit 128.

[0112] According to a sixth step S6, the torsion bar 102 and the second

[0113] Steering torque transmission component 106 is pressed together by means of a second cylinder press fit 130.

[0114] Step S5 can occur before step S6. Alternatively, step S6 can occur before step S5. Alternatively, steps S5 and S6 can occur simultaneously.

[0115] LIST OF REFERENCE SYMBOLS

[0116] 100 Steering torque transmission assembly

[0117] 102 Torsion bar

[0118] 104 first steering torque transmission component or steering shaft

[0119] 106 second steering torque transmission component or steering spindle

[0120] 108 first fortification section

[0121] 110 second fastening section

[0122] 112 first torsion bar attachment section

[0123] 114 second torsion bar attachment section

[0124] 116 first mutually pressed fastening section

[0125] 118 second mutually pressed fastening section

[0126] 120 first final section

[0127] 122 second end section

[0128] 124 Sprocket of the first fastening section

[0129] 126 Gear ring of the second fastening section

[0130] 128 first cylinder interference fit

[0131] 130 second cylinder interference fit

[0132] 132 first blind hole

[0133] 134 second blind hole

[0134] 136 Middle section

[0135] 138 first blind hole base area

[0136] 140 second blind hole base area

[0137] 142 mutual overlap area

[0138] 144 mutual interlocking

[0139] 146 internal gearing

[0140] 148 external gearing

[0141] 150 guide section

[0142] 152 Torsion bar guide section

[0143] 154 final section

Claims

PATENT CLAIMS 1 . Steering torque transmission assembly (100) for a vehicle steering gear, in particular a ball screw steering gear for a commercial vehicle, comprising: - at least one torsion bar (102); - at least one first steering torque transmission component (104), in particular a steering shaft; and - at least one second steering torque transmission component (106), in particular a steering spindle, wherein the torsion bar (102) has at least one first, in particular cylindrical, fastening section (108) and at least one second, in particular cylindrical, fastening section (110), wherein the first steering torque transmission component (104) has at least one first torsion bar fastening section (112), and wherein the second steering torque transmission component (106) has at least one second torsion bar fastening section (114);wherein the first steering torque transmission component (104) and the torsion bar (102) form at least one first mutually pressed fastening section (116) in the assembled state by means of the first fastening section (108) and the first torsion bar fastening section (112), and / or wherein the second steering torque transmission component (106) and the torsion bar (102) form at least one second mutually pressed fastening section (118) in the assembled state by means of the second fastening section (110) and by means of the second torsion bar fastening section (114); 2. Steering torque transmission assembly (100) according to claim 1, characterized in that the first fastening section (108) and the first torsion bar fastening section (112) form an interference fit in the assembled state to form the first mutually pressed fastening section (116), and / or wherein the second fastening section (110) and the second torsion bar fastening section (114) form an interference fit in the assembled state to form the second mutually pressed fastening section (118).

3. Steering torque transmission assembly (100) according to claim 1 or claim 2, characterized in that the torsion bar (102) is formed as solid material axially at least within the first fastening section (108) and / or axially at least within the second fastening section (110).

4. Steering torque transmission assembly (100) according to one of the preceding claims, characterized in that the torsion bar (102) has at least a first end portion (120) and at least one second end portion (122) arranged opposite the first end portion (120), wherein the first fastening portion (108) is arranged on the first end portion (120) and wherein the second fastening portion (110) is arranged on the second end portion (122).

5. Steering torque transmission assembly (100) according to one of the preceding claims, characterized in that the first fastening section (108) has at least in sections a toothed ring (124) and / or wherein the second fastening section (110) has at least in sections a toothed ring (126).

6. Steering torque transmission assembly (100) according to one of the preceding claims, characterized in that the first fastening section (108) has at least a first external nominal dimension and the second fastening section (110) has at least a second external nominal dimension, wherein the first external nominal dimension and the second external nominal dimension are the same and / or are tolerated by means of an identical external tolerance dimension.

7. Steering torque transmission assembly (100) according to claim 6, characterized in that the same external tolerance dimension has the same tolerance field position in the range from j to zc, in particular in the range from p to zc, and / or the same tolerance field size in the range from IT01 to IT18 according to ISO standard ISO 286.

8. Steering torque transmission assembly (100) according to one of the preceding claims, characterized in that the first torsion bar fastening section (112) has at least a first nominal inner dimension and the second torsion bar fastening section (114) has at least a second nominal inner dimension, wherein the first nominal inner dimension and the second nominal inner dimension are the same and / or are tolerated by means of a same internal tolerance dimension.

9. Steering torque transmission assembly (100) according to claim 8, characterized in that the same internal tolerance dimension has an H tolerance field and / or an equal tolerance field size in the range from IT01 to IT18 according to ISO standard ISO 286.

10. Steering torque transmission assembly (100) according to one of the preceding claims, characterized in that the first fastening section (108) and the first torsion bar fastening section (112) form at least one first cylinder interference fit (128), in particular a cylinder longitudinal interference fit, and / or wherein the second fastening section (110) and the second torsion bar fastening section (114) form at least one second cylinder interference fit (130), in particular a cylinder longitudinal interference fit.

11. Steering torque transmission assembly (100) according to one of the preceding claims, characterized in that the first steering torque transmission component (104) has at least one first blind hole (132) in which the first torsion bar fastening section (112) is arranged, and wherein the second steering torque transmission component (106) has at least one second blind hole (134) in which the second torsion bar fastening section (114) is arranged.

12. Steering torque transmission assembly (100) according to one of the preceding claims, characterized in that the first steering torque transmission component (104) and / or the second steering torque transmission component (106) and / or the torsion bar (102) have at least one alignment element for mutual alignment of the first and second steering torque transmission components (104, 106).

13. Steering gear for a vehicle, in particular a ball screw steering gear for a commercial vehicle, comprising at least one steering torque transmission assembly (100) according to one of the preceding claims.

14. A method for assembling at least one steering torque transmission assembly (100) for a vehicle steering gear, in particular a ball screw steering gear for a commercial vehicle, comprising the following steps: - Providing at least one torsion bar (102), in particular according to one of the preceding claims 1 to 12; - Providing at least one first steering torque transmission component (104), in particular a steering shaft, in particular according to one of the preceding claims 1 to 12; - Providing at least one second steering torque transmission component (106), in particular a steering spindle, in particular according to one of the preceding claims 1 to 12; - aligning the torsion bar (102) and / or the first steering torque transmission component (104) and / or the second steering torque transmission component (106) with each other; - pressing the torsion bar (102) and the first steering torque transmission component (104) by means of a first cylinder press fit (128); and - Pressing the torsion bar (102) and the second steering torque transmission component (106) by means of a second cylinder press fit (130).

Citation Information

Patent Citations

  • Shaft arrangement and steering gear with a shaft arrangement

    DE102020119281A1

  • Method for chipless connection of the pinion or input shaft to the torsion bar of a power steering system

    DE102010055298A1

  • Steering shaft for a motor vehicle steering system

    WO2015028122A1