Bearing element for a linear rolling guide
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- SCHAEFFLER TECHNOLOGIES AG & CO KG
- Filing Date
- 2025-11-26
- Publication Date
- 2026-08-06
Smart Images
Figure DE2025101115_06082026_PF_FP_ABST
Abstract
Description
[0001] P250762
[0002] - 1 - Bearing element for a linear roller guide
[0003] Field of invention
[0004] The invention relates to a bearing element for a linear roller guide with a support body. Such elements can simultaneously absorb a load perpendicular to the direction of movement and tilting moments about the longitudinal and transverse axes of the direction of movement.
[0005] The use of such a device is conceivable in general mechanical engineering as well as in the field of automotive engineering.
[0006] State of the art
[0007] German publication DE 101 20828 A1 describes a bearing element designed as a recirculating roller bearing. The carrier body is formed from a thin-walled, M-shaped housing bushing with a flat, central section that forms the rolling bearing raceway. Cylindrical rollers or cylindrical needles are used as rolling elements. The rolling element recirculation channel, consisting of a return channel and two deflection channels, is formed from a plastic insert. The rolling elements within the recirculation channel can rotate as many times as desired.
[0008] Disclosure of the invention
[0009] The invention is based on the objective of providing a compact, cost-effectively manufacturable bearing element.
[0010] The object of the invention is achieved by a bearing element having the features specified in the characterizing part of claim 1. Further preferred embodiments and developments of the invention can be found in the dependent claims, the figures, and the accompanying description.
[0011] Accordingly, the problem is solved by a bearing element for a linear rolling guide with a rolling element circulation device, comprising a support body, P250762
[0012] -2 -a support channel for guiding rolling elements, wherein the support channel is limited in a load-transmitting direction by the support body, a recirculation channel for returning the rolling elements, with a return channel and two deflection channels which connect the support channel and the return channel at their respective ends, wherein the support body has a hollow profile with a hollow chamber.
[0013] Hollow sections are defined as structural steel profiles with concentric, rectangular, oval, or other closed cross-sections. Such hollow sections are also often referred to as tubes. However, since tubes are generally understood to be components with exclusively concentric cross-sections, this application uses the term hollow section to clarify that it expressly does not refer only to semi-finished products with concentric cross-sections. Rather, the design of the cross-sectional profile can be adapted by a person skilled in the art to the specific application. Thus, by dimensioning and designing the hollow section, a person skilled in the art can advantageously determine the stiffness in the support direction to suit the specific application.
[0014] In an advantageous embodiment of the invention, the support channel is arranged on an outer surface of the hollow profile, while the return channel runs through its hollow chamber. The support body forms a contact surface on which the rolling elements run, transmitting the forces acting on the counter body to the support body. Simultaneously, a space must be provided in which the rolling elements can be returned after they have left the load area by means of the rolling motion. In the present invention, this can be achieved very advantageously by means of the hollow chamber enclosed by the hollow profile, thus allowing for a particularly compact design.
[0015] The hollow profile can preferably be made of hardened or hardenable steel. The hollow profile can thus form the rolling bearing raceway of the bearing element and transmit the forces from the rolling elements to the surrounding structure. Consequently, at least a local hardening process in the area of the rolling element raceway is advantageous. P250762
[0016] - 3 -
[0017] The hollow profile can be manufactured particularly cost-effectively by deep drawing or, alternatively, by cutting it to length from a profile tube or strip using bending and welding. By selectively designing the hollow profile wall thickness and / or length-to-width ratio, the stiffness and spring properties of the linear roller guide can be tailored to specific requirements. Alternatively, sections of the hollow profile can be designed to be elastically resilient, similar to a bending beam. By appropriately modifying the stiffness, edge stresses caused by torque application around the longitudinal axis of movement can be reduced. The same can be achieved by profiling the outer surface of the hollow profile in the area of the rolling element raceway, perpendicular to the longitudinal axis and / or by giving it a convex shape when viewed in a cross-sectional view.Thus, the hollow profile is an efficient and inexpensive means of designing the linear roller guide for the desired application.
[0018] At the same time, the outer surface of the hollow profile opposite the contact surface of the rolling elements provides another surface, via which the forces introduced into the bearing element can be advantageously transferred into the surrounding structure, for example a housing.
[0019] It is further proposed that the at least one rolling element recirculation device comprises the following sections: a support channel configured to guide the rolling elements so that they come into contact with the running surface of the counter body; and a recirculation channel that continuously returns the rolling elements, after they have passed through the support channel, to the beginning of the support channel in a closed loop. The recirculation channel, in turn, comprises a first deflection channel, a return channel, and a second deflection channel. The first deflection channel is configured to space the rolling elements away from the running surface, redirect their direction of movement, and guide them into the return channel, which may be designed to move the rolling elements substantially parallel to the support channel. The return channel opens into a second deflection channel, which is configured to guide the rolling elements from the return channel back into the support channel. This results in a P250762
[0020] -4 -This allows the rolling elements to rotate any number of times within the rolling element circulation device, enabling low-friction displacement of the counter-body relative to the bearing element. The designations first and second deflection channels, as well as the described functions of the deflection channels, remain valid in one direction of movement. In the opposite direction of movement, the functions are inverted accordingly.
[0021] The fact that the return channel runs essentially parallel to the support channel means that it can also have a variable shape, such as an arc, while the support channel is straight. The design of the deflection channels, which in a basic configuration cause a 180° redirection of the rolling element movement, can also deviate from a constant deflection radius. For example, several arc segments with different radii can be arranged in a row, or the path can be defined by any other function or point arrangement. In particular, the shape of the deflection channels can be advantageously designed to redirect the rolling element movement in the smoothest possible way, thus reducing noise.Cases can also occur in which the deflection channels divert the rolling elements by less than 180° and the return channel, due to its, for example, arc-shaped design, takes over part of the deflection. In the limiting case of a design, the deflection channels and the return channel merge. In any case, for the purposes of the application, the return channel is defined as the part of the recirculation channel that runs in the area of the recirculation channel opposite the support channel. Functionally, this design means that the support channel represents the load zone for the rolling elements, while the rolling elements in the recirculation channel are free of operating load.
[0022] In an advantageous embodiment of the invention, the rolling elements are designed as cylindrical rollers. Depending on the dimensions and the diameter-to-length ratio, these can be cylindrical rollers, cylindrical needle rollers, or needle rollers, or other types of cylindrical rollers such as barrel rollers. The bearing design is preferably full complement, meaning that, for increased power transmission capacity and a compact design, the guidance of the rolling elements is reduced.
[0023] - 5 - Cages or similar elements that increase the distance between the rolling elements are omitted.
[0024] Preferably, the cylindrical rollers are solid bodies; this makes the rolling elements more stable and able to withstand higher forces. The resulting line contact with the flat rolling element raceway reduces surface pressures on both the support body and the component in contact, thus increasing service life. Furthermore, cylindrical rolling elements have the advantage that even in a single-row configuration, they can absorb and compensate for force application that is not centered in the middle of the rolling elements. Such force application occurs particularly when the component running against the bearing element is not only supported by the bearing element but also prevented from tilting. Distributing the forces across multiple rolling elements ensures low-friction, virtually wear-free, and positionally accurate bearing operation.This also allows for a low displacement force in the longitudinal direction, which is independent or at least almost independent of the acting torsional torques.
[0025] In another embodiment, the rolling elements designed as cylindrical rollers can also have a shell profile which is suitable for reducing edge pressures in the rolling contact when supporting torques.
[0026] In an advantageous embodiment, the recirculation channels are made of plastic, preferably by injection molding. Generally, recirculation channels made of plastic result in particularly quiet operation.
[0027] Preferably, the radially inner guide surface of the first deflection channel, the second deflection channel, and the return channel is formed by two injection-molded plastic deflection pieces. These two inner parts can each have positive-locking connecting elements, for example, in the form of pins and pin receptacles, so that they are positioned relative to each other. P250762
[0028] - 6 -can. Furthermore, it is possible for both inner parts to be designed as identical parts, which creates a significant economic advantage with regard to tooling costs and avoids incorrect assembly.
[0029] Preferably, the radially outer guide surface of the first and second deflection channels is formed by two additional outer parts made of plastic, manufactured using injection molding. This advantageous design eliminates the need for an additional intermediate component. These two outer parts can also each have positive-locking connecting elements, for example, in the form of pins and pin receptacles, allowing them to be positioned relative to each other. Furthermore, this design makes it possible to manufacture both outer parts as identical components, resulting in significant economic advantages in terms of tooling costs and preventing assembly errors.
[0030] In a particularly advantageous embodiment, the two outer parts, which include the radially outer guide surfaces of the deflection channels, also form the outer housing of the bearing element. These components, referred to as end pieces or outer parts, can be positioned relative to each other and connected by appropriate design of the connection area, preferably by a snap-fit connection. A snap-fit connection has the advantage that it can be designed to be detachable and is easy to assemble. Alternatively, other connection technologies are also possible, such as positive-locking connections using additional components like clamps, friction-locking connections, for example, by a longitudinal press fit, or even material-locking connections, for example, by fusing the two housing halves using a laser welding process.
[0031] Preferably, lubricant reservoir channels, preferably in the form of grooves, are incorporated into the inner and / or outer guide surfaces of the deflection and return channels. Such lubricant reservoirs ensure maintenance-free operation with lifetime lubrication. The lubricant reservoirs can be filled through at least one opening in the head pieces. The outer P250762
[0032] - 7 - The lubricant reservoir can be filled directly, while the inner lubricant reservoir can be filled by appropriately designing the overall clearance between the rolling elements. If this is not possible, a separate supply bore can be provided for the inner reservoir. Grease is particularly suitable as a lubricant because, due to its consistency and adhesive properties, it remains in the bearing element for a longer period and thus ensures a continuous supply of lubricant to the rolling contacts throughout the entire service life.
[0033] In an advantageous embodiment, the return channel in the inner parts is opened on the inside or outside in the form of a C-profile, thus forming a lubricant channel in a simple manner, limited by the inner surface of the support body.
[0034] Advantageously, the grooves of the lubricant reservoir end in the radially outer guide surfaces of the deflection channels of the outer parts shortly before exiting the component in the direction of the support channel, so that as little lubricant as possible is carried out of the lubricant reservoir into the rolling element running area.
[0035] In an advantageous embodiment, the two outer parts are equipped with strip-shaped wipers to retain the lubricant in the reservoir area. In a further embodiment, the wipers are continuous around the roller area, meaning there are transverse and longitudinal wipers. The wipers can be integrated directly into the injection-molded component and can be made of the same material as the injection-molded part or of a softer material, thus being incorporated using a two-component injection molding process. Alternatively, the wipers can be used as separate components.
[0036] In an advantageous embodiment, the outer parts have press-fit ribs on their outer circumferential surfaces. These enable a permanent, backlash-free fastening in the surrounding housing without placing particularly high demands on the connection fits. The press-fit ribs can also be made of a soft, elastic material and either formed by injection molding (P250762).
[0037] - 8 -can be injection-molded or assembled as separate components. In the case of assembly as a separate component, it can be advantageous to use O-rings or other elastic bands. The elastic connection to the surroundings allows deformations, for example on the counterbody, to be absorbed effectively without immediately leading to a direct overload.
[0038] In a further embodiment of the outer parts, recesses are provided in a suitable manner to facilitate gripping by an assembly device, including an assembly robot.
[0039] In a further advantageous embodiment, the bearing element comprises at least two rolling element circulation channels, each with a plurality of rolling elements arranged therein. This allows both the number of rolling elements available for support against the running surface of the steering rod to be increased, and the support spacing to be enlarged, thus increasing the load-bearing capacity of the bearing assembly and enabling it to reliably absorb larger torsional torques.
[0040] If at least two rolling element recirculation devices are provided, they preferably run parallel to each other, thus enabling a compact design. When using cylindrical rolling elements, the rows of rolling elements can either run against each other, meaning the rolling elements of the adjacent recirculation devices touch at their side faces, or preferably be separated from each other by a lateral guide. This separation can be achieved either by a stationary guide flange between the rows of rolling elements or, alternatively, by means of conventional cage segments or cage chains.
[0041] A cost-effective design with at least two rolling element recirculation devices involves using balls instead of cylindrical rolling elements. Torque support against tilting is then achieved through the design spacing of the rolling element rows and the inherently higher point contact resistance (P250762).
[0042] - 9 - Surface pressure is adjusted by a specialist to the load case by means of a constructive design of the spacing of the support channels.
[0043] A preferred application of the invention is the torque support of a steering rod, which must be supported against rotation but also be adjustable with low friction in its longitudinal direction under the influence of the torsional torque. Such steering rods are found in conventional mechanical and steer-by-wire steering systems. The invention can also be used in other technical fields with similar operating conditions, i.e., where an axle or rod must be secured against rotation but simultaneously be movable with low friction.
[0044] Description of the drawings
[0045] The application is explained below with reference to preferred embodiments and the accompanying figures. These show:
[0046] Fig. 1 shows a perspective view of a first embodiment of a bearing element,
[0047] Fig. 2 is an exploded view of the bearing element according to Fig. 1,
[0048] Fig. 3 shows a first perspective sectional view of the bearing element according to Fig. 1,
[0049] Fig. 4 shows a second perspective sectional view of the bearing element according to Fig. 1.
[0050] Fig. 5 shows a perspective view of an outer part of the bearing element according to Fig. 1.
[0051] Fig. 6 shows a sectional view of the bearing element according to Fig. 1, P250762
[0052] - 10 - Fig. 7 shows a sectional view of a second embodiment of a bearing element,
[0053] Fig. 8 shows a sectional view of a third embodiment of a bearing element,
[0054] Fig. 9 shows a sectional view of a fourth embodiment of a bearing element and
[0055] Fig. 10 shows a perspective view of a steering rod with a bearing element.
[0056] Figure 1 shows a perspective view of a bearing element 1, which has a single rolling element recirculation device 2. The rolling elements 3 are designed as cylindrical rollers 4. They run in the support channel 5, the lateral guide surfaces 6 of which are formed by the first outer part 7 and the second outer part 8. The two outer parts 7 and 8 simultaneously and jointly function as the outer housing 9 of the bearing element 1. The outer housing 9 is equipped with press-fit ribs 10, which enable an interference fit in a surrounding assembly (not shown). These press-fit ribs 10 absorb the deformations during the joining process, thereby preventing excessive stress on the outer housing 9 or the surrounding assembly. The outer parts 7 and 8 are identical and are connected via a snap connection using snap fingers 11.In addition, the outer housing has 9 recesses 12 which enable safe handling of the bearing element 1 by a gripping tool during the manufacturing and assembly process.
[0057] Figure 2 shows the bearing element 1 from Figure 1 in a perspective exploded view. The bearing element 1 has the first outer part 7 and the second outer part 8, which together form the outer housing 9. The laterally arranged snap finger 11 of one outer part engages in a snap lug 13 of the other outer part. The two outer parts 7 and 8 are designed as identical parts. (See further P250762)
[0058] - 11 -For the external features of the outer parts 7, 8, reference is made to the descriptions of Figures 1 and 5. The outer parts 7, 8 together form the lateral guide surfaces 6 of the support channel 5 for the cylindrical rollers 4. A raised clamping rib 14 is provided in the guide surface 6, which holds the cylindrical rollers 4 in the support channel 5 by frictional engagement. In the load-transmitting direction, the support channel 5 is bounded by the support surface 15 of the support body 16. The support body 16 is designed as a hollow profile 17. With its outer surface 18 opposite the support surface 15, the bearing element 1 is supported in the load direction against an surrounding structure (not shown). The return channel 19 runs through the hollow chamber 20 of the hollow profile 17 and is formed by the first inner part 21 and the second inner part 22.The two inner parts 21, 22 are designed as identical parts and contact each other via a contact surface 23 in the center of the return channel 19. For positioning the inner parts 21, 22 relative to each other, a pin 24 and a corresponding pin receptacle 25 are formed from the contact surface 23. The inner parts 21, 22 also form the first and second inner curves 26, 27 as well as the lateral guide 28 of the deflection channels 29, 30. The C-shaped open design of the inner parts 21, 22 within the hollow chamber 20 creates a free volume to serve as a lubricant reservoir 31. In the first embodiment of the bearing element 1 shown in Figures 1 to 5 and 9, the first and second outer parts 7, 8 as well as the first and second inner parts 21, 22 are designed as identical parts. Thus, the bearing element 1 shown has an axially symmetrical structure around an axis of symmetry that pierces the support surface 15 centrally and at right angles.
[0059] Figure 3 shows the bearing element 1 from Figures 1 and 2 in a perspective longitudinal section. The recirculating channel 32, over which the rolling elements 3 pass after leaving the support channel 5 due to the movement of a counterbody (not shown), consists of a first and second deflection channel 29, 30 and a return channel 19. Via the first deflection channel 29, formed by the first inner part 21 and the first outer part 7, the rolling elements 3, as soon as they reach the end of the support channel 5 through movement, are distanced from the contact surface of the counterbody (not shown) by the first outer curvature 33, which is formed by the first outer part 7, and their movement is deflected by 180°. According to P250762
[0060] - 12 - After deflection, they enter the return channel 19, which runs through the hollow chamber 20 of the hollow profile 17 of the support body 16, see also Figure 2. The return channel 19 is formed by the first and second inner parts 21, 22. After the return channel 19, the rolling elements 3 enter the second deflection channel 30, formed by the second inner part 22 and the second outer part 8, which forms the second outer curvature 34, and are guided back to the support channel 5 in the direction of movement.
[0061] Figure 4 shows a perspective cross-section of the bearing element 1 of Figures 1 to 3. The rolling elements 3, designed as cylindrical rollers 4 and located in the support channel 5, are guided by the lateral guide surfaces 6 formed by the outer parts 7, 8. In the load-transmitting direction, the support channel 5 is bounded by the support surface 15 formed by the support body 16. The bearing element 1 is supported in the load direction against an surrounding structure (not shown) by its outer surface 18 opposite the support surface 15. The return channel 19 runs through the hollow chamber 20 of the support body 16 and is formed by the first inner part 21. The C-shaped open cross-section of the first inner part 21 creates a free volume to serve as a lubricant reservoir 31.Furthermore, a groove is provided on the surface of the first inner part 21, which delimits the return channel 19 towards the support channel 5, to serve as an additional lubricant reservoir 31. A pin 24 and a pin receptacle 25 are provided for positioning the first inner part 21 and 22 relative to the second inner part 22. When the two inner parts 21 and 22, which are identical, are positioned relative to each other, the pin 24 of the first inner part 21 engages in the pin receptacle 25 of the second inner part 22, and vice versa.
[0062] Figure 5 shows a first or second outer part 7, 8 of the bearing element 1 shown in Figures 1 to 4. Raised clamping ribs 14 are provided on the lateral guide surfaces 6, which hold the rolling elements 3 in the support channel 5 by frictional engagement. The outer part 7, 8 forms the outer curvature 33, 34 of the deflection channel 29, 30 running through it. A groove-shaped recess is formed in the outer curvature 33, 34 as a lubricant reservoir 31. The recess ends within the P250762
[0063] - 13 - Curvature 33, 34, so that the lubricant remains largely in the lubricant reservoir 31 and is not excessively conveyed into the support channel 5. A snap finger 11 is formed on one side of the outer part 7 and the corresponding snap nose 13 on the other side. An opening 36 is provided on the outer surface 18 opposite the support channel 5, through which lubricant can be introduced into the lubricant reservoir 31 after the bearing element 1 has been installed. Adjacent to the support channel 5, half of the recesses 12 for the handling device described in the description of Figure 1 are provided in the outer part 7.
[0064] Figure 6 shows the bearing element 1 of Figures 1-5 in an orthogonal sectional view. Reference is made to the figure description of Figure 4.
[0065] Figure 7 shows a second embodiment of the bearing element 1 in an orthogonal sectional view. In contrast to the embodiment shown in Figure 6, the bearing element 1 is designed with two rows of rolling elements with cylindrical rollers 4. The rolling elements 3 of the rows contact each other laterally along the central axis 35.
[0066] Figure 8 shows a third embodiment of the bearing element 1 in an orthogonal sectional view. In contrast to the embodiment shown in Figure 7, the two rows of rolling elements are separated from each other by a lateral guide 28. The lateral guide 28 in the area of the support channel 5 is formed by the outer parts 7, 8, and in the area of the return channel 19 by the inner parts 21, 22. In the two deflection channels 29, 29, which are not visible in Figure 8, the lateral guide 28 can optionally be formed by either the inner parts 21, 22 or the outer parts 7, 8.
[0067] Figure 9 shows a fourth embodiment of the bearing element 1 in an orthogonal sectional view. In contrast to the embodiment shown in Figure 8, the elements forming the inner side surfaces of the rolling element rows are P250762
[0068] - 14 -spaced apart from each other. The lateral guide 28 in the area of the return channel 19 is formed by the inner parts 21, 22 as shown in Figure 8.
[0069] Figure 10 shows a bearing element 1 and a steering rod 37. The bearing element 1 contacts a contact surface 23 of the steering rod 37. Thus, the bearing element 1 can absorb forces orthogonal to the contact surface 23, as well as torques about the longitudinal axis 38 of the steering rod 37, and therefore acts as an anti-rotation device for the steering rod 37 against a steering rod housing (not shown) in which the bearing element 1 is positioned. This is also important when the bearing element 1 is used for other devices. P250762
[0070] - 15 - List of reference symbols
[0071] 1 bearing element
[0072] 2 rolling element circulation device
[0073] 3 rolling elements
[0074] 4 Cylindrical roller
[0075] 5 support channel
[0076] 6 lateral guide surfaces
[0077] 7 first outer part
[0078] 8 second outer part
[0079] 9 outer casings
[0080] 10 Press-in ribs
[0081] 11 Trigger Finger
[0082] 12 Exclusion
[0083] 13 Snap-nose
[0084] 14 clamping ribs
[0085] 15 Support surface
[0086] 16 carrier bodies
[0087] 17 Hollow profile
[0088] 18 outdoor area
[0089] 19 Return channel
[0090] 20 hollow chamber
[0091] 21 first inner part
[0092] 22 second inner part
[0093] 23 Contact area
[0094] 24 cones
[0095] 25 pin holders
[0096] 26 first inner curvature
[0097] 27 second inner curvature
[0098] 28 lateral guide
[0099] 29 first deflection channel
[0100] 30 second deflection channel
[0101] 31 SchmiermittelreservoirP250762
[0102] - 16 - 32 Circulation Channel
[0103] 33 first outer curvature
[0104] 34 second outer curvature
[0105] 35 Center axis
[0106] 36 Opening
[0107] 37 Handlebar
[0108] 38 Longitudinal axis
Claims
P250762 - 17 - Patent claims 1. Bearing element (1 ) for a linear rolling guide with a rolling element circulation device (2), comprising - a carrier body (16), - a support channel (5) for guiding rolling elements (3), wherein the support channel (5) is limited in a load-transmitting direction by the support body (16), - a circulation channel (32) for returning the rolling elements (3), with - a return channel (19) and - a first and a second deflection channel (29, 30) which connect the support channel (5) and the return channel (19) at their respective ends, characterized in that the support body (16) has a hollow profile (17) with a hollow chamber (20).
2. Bearing element (1) according to claim 1 , characterized by the fact that the support channel (5) is bounded by an outer surface (18) of the hollow profile (17) and the return channel (19) runs through its hollow chamber (20).
3. Bearing element (1) according to one of the preceding claims, characterized by the fact that - a first inner part (21) forms a first inner curvature (26) of the first deflection channel (29), - a second inner part (22) forms a second inner curvature (27) of the second deflection channel (30), - a first outer part (7) forms a first outer curvature (33) of the first deflection channel (29) and - a second outer part (8) forms a second outer curvature (34) of the second deflection channel (30). P250762 - 18 - 4. Bearing element (1 ) according to claim 3 characterized by an outer housing (9) consisting of the first (7) and the second outer part (8).
5. Bearing element (1 ) according to claim 3 or 4, characterized in that the first (7) and the second outer part (8) are snapped together.
6. Bearing element (1 ) according to one of claims 3 to 5, characterized in that the first (7) and the second outer part (8) are designed as identical parts.
7. Bearing element (1 ) according to one of claims 3 to 6, characterized in that the first inner part (21) and the second inner part (22) are designed as identical parts.
8. Bearing element (1 ) according to one of claims 4 to 7, characterized in that the outer housing (9) has press-fit ribs (10) made of the same or a softer material than the base material of the outer housing (9).
9. Bearing element (1 ) according to one of the preceding claims, characterized in that the bearing element (1) has two rows of rolling elements (3).
10. Bearing element (1 ) according to one of the preceding claims, characterized in that the bearing element (1) has cylindrical rollers (4) as the rolling elements (3).
11. Bearing element (1) according to claim 9, characterized in that the rolling elements (3) are balls and the rows are separated from each other by a lateral guide (28). P250762 - 19 - 12. Steering unit with a bearing element (1) according to one of the preceding claims.