Steering gear

Abstract

The invention relates to a steering gear (1) comprising: - a housing (2); - a first and a second displacement element (10, 11); - a force-absorbing element (9); - an output interface (30), the displaceable displacement elements (10, 11) being provided in an interior of the housing (2) and dividing the latter into displacement chambers (3, 4, 5), the displacement elements (10, 11) each having force transmission elements (12, 13) which are mechanically engaged with the force-absorbing element (9), which can be rotated about an axis of rotation (14) and is mechanically coupled to the output interface (30), the steering gear (1) being designed such that the displacement elements (10, 11) can be displaced into and / or out of the displacement chambers (3, 4, 5) by supplying and / or discharging pressure medium such that force effects occur via the engagement between the force-absorbing element (9) and the force transmission elements (12, 13) such that a torque is applied to the output interface (30). Furthermore, a steering unit (50), an axle unit (100) and a vehicle (200) are disclosed.

Description

[0001] 2024PF00142

[0002] 1

[0003] DESCRIPTION

[0004] steering gear

[0005] The present disclosure relates to a steering gear for a vehicle, a steering unit, an axle unit and a vehicle.

[0006] Steering gears are used to generate a steering input, such as a steering torque or steering force, which is transmitted via a steering mechanism, such as a steering linkage, a lever arm, or a rocker arm and / or a combination of pinion and rack, to a steered axle to steer the wheels. Particularly in the commercial vehicle sector, steering gears are known that generate this steering input with hydraulic assistance. For example, a piston is driven or displaced by hydraulic pressure, whereby the displacement is converted into a steering input and transmitted to the steering mechanism. By displacing the displacement element as a result of the hydraulic pressure, a steering input of a comparatively high magnitude can be generated, which is particularly advantageous for commercial vehicles with relatively high axle loads.

[0007] Nevertheless, to generate the corresponding steering parameters, a minimum dimensioning of the piston or the displacement space in which the piston is guided is necessary, which ultimately leads to installation space problems.

[0008] The purpose of this disclosure is therefore to provide a way to generate appropriate steering parameters, thereby making better use of the available space.

[0009] This problem is solved by the subject matter of the independent claims. Further details can be found in the dependent claims, the description, and the accompanying drawings.

[0010] K07949WO / SfN 2024PF00142

[0011] 2

[0012] According to a first aspect, a steering gear is provided for a vehicle. The steering gear has a housing, a first displacement element, a second displacement element, a force-receiving element, and an output interface.

[0013] The first and second displacement elements are located within the same interior space of the housing. These elements divide the interior space into displacement chambers. By arranging the displacement elements in a single housing, the steering gear can be designed with a smaller footprint.

[0014] The first and second displacement elements are designed to be movable. This allows the displacement elements to be used to generate the steering input.

[0015] The first displacement element has a first force transmission element. The second displacement element has a second force transmission element. A force acting on the respective displacement element, e.g., from pressure exerted on the respective displacement element from a displacement chamber, can thus be transmitted to the respective force transmission element.

[0016] The first force transmission element is mechanically engaged with the force receiving element. The second force transmission element is mechanically engaged with the force receiving element. In this way, a force or displacement of the respective displacement elements can be transmitted to the force receiving element via the respective force transmission elements.

[0017] The force-receiving element is rotatable about an axis of rotation and mechanically coupled to the output interface. The force-receiving element can, in particular, be designed as a pinion, wherein the first force transmission element and the second force transmission element engage with the pinion by means of appropriately designed teeth. The force transmission elements can be designed as racks. The force-receiving element can be mounted on a shaft of the steering gear that is rotatable about the axis of rotation. The shaft 2024PF00142

[0018] 3 can extend from the housing and have the output interface on the section projecting from the housing, e.g., at the free end of this section. Alternatively, the force-receiving element can be designed as a lever arm or cam lever. These configurations of the force-receiving element are particularly suitable for small rotation angles of the force-receiving element about the axis of rotation. With such a configuration of the force element, the first force transmission element and the second force transmission element are designed accordingly to realize the mechanical engagement between the force transmission element and the first and second force-receiving elements, respectively.

[0019] The force-absorbing element can be formed integrally with the shaft, which ensures a high load-bearing capacity of the connection between the force-absorbing element and the shaft. Alternatively, the force-absorbing element can also be formed separately and fixed to the shaft in a rotationally fixed manner. This allows for simpler assembly and maintenance of the steering gear components.

[0020] The steering gear is designed such that the first displacement element and the second displacement element can be moved into and / or out of at least one of the displacement chambers by the addition and / or removal of pressure medium, so that a first force is applied to the force-receiving element via the engagement between the force-receiving element and the first force-transmission element, and a second force is applied to the force-receiving element via the engagement between the force-receiving element and the second force-transmission element. Through the mechanical coupling of the force-receiving element to the output interface, the first and second forces impart a torque to the output interface.

[0021] To achieve high forces, the pressure medium can be hydraulic fluid.

[0022] A steering parameter can be, in particular, a steering torque or a steering force. 2024PF00142

[0023] 4

[0024] The torque of the output interface can be used as a steering input. Therefore, the output interface can be designed for mechanical coupling with a steering mechanism, via which the steered wheels of an axle can be steered. In other words, the output interface can be a section designed for coupling and transmitting the steering input to a steering mechanism. For example, the output interface can be designed for rotationally fixed coupling with the steering mechanism. Alternatively, a transmission stage can be provided that translates the torque of the output interface into a torque that constitutes the steering input. The mechanical coupling with a steering mechanism can then be achieved via the transmission stage. Alternatively, a conversion unit can be provided that is designed to generate a force as a steering input from the torque of the output interface. The conversion unit can, for example, be...This could be a lever arm or a rocker arm that is rotationally fixed to the output interface. The mechanical coupling with a steering mechanism can then be achieved via the conversion unit.

[0025] In summary, it can be said that the torque of the output interface can be used directly as the steering parameter, or the steering parameter can be generated from the torque of the output interface via an intermediate element, such as a transmission stage or a conversion unit.

[0026] The first and / or second displacement element can be designed as pistons guided within the interior of the housing. This allows for a compact design by integrating both displacement elements into the same housing.

[0027] The first displacement element is designed to be displaceable parallel to a first displacement direction. Alternatively or additionally, the second displacement element is designed to be displaceable parallel to a second displacement direction. The displacement directions preferably lie in a common plane to achieve a compact design of the steering gear. The 2024PF00142 is particularly preferred.

[0028] 5. The first and second displacement directions are parallel to each other. In this way, a parallel arrangement of the displacement elements can be achieved, minimizing their distance to create a more compact design. In particular, it can be provided that the first and second displacement directions lie on a common line, with the displacement elements thus being designed to be displaceable parallel to this line. In this way, a compact design perpendicular to the first displacement direction, perpendicular to the second displacement direction, or perpendicular to the line can be achieved. In this case, the first and second displacement directions can be identical.

[0029] As described above, the output interface can be designed as a section of a shaft coupled to the force-receiving element. A torque applied to the force-receiving element can thus be transmitted from the force-receiving element to the output interface. This torque can be generated, for example, by a force applied to the force-receiving element by one or more force transmission elements offset from the axis of rotation of the force-receiving element or the shaft.

[0030] The axis of rotation of the shaft or force-absorbing element can be oriented perpendicular to the direction of displacement in a projection plane that also contains the direction of displacement. This allows for the force to be introduced into the force-absorbing element with the highest possible force component perpendicular to the axis of rotation, in order to generate the highest possible torque from the displacement of the displacer elements.

[0031] One or more of the force transmission elements can extend essentially parallel to the displacement direction of the respective displacement element. In this way, a design of the force transmission element is possible in which engagement elements, such as teeth of a gear, can be arranged on the respective force transmission element along the displacement direction, which engage with corresponding engagement elements of the force receiving element. 2024PF00142

[0032] 6. This allows for the transmission of force from the respective force transmission element to the force receiving element. For this purpose, the force receiving element can be designed, in particular, as a gear or pinion.

[0033] The first displacement element and / or the second displacement element can have surfaces extending essentially transversely to the respective direction of displacement, which face the respective displacement space and on which the pressure of the pressure medium within the displacement space can act.

[0034] The first displacement element and the first force transmission element can be arranged eccentrically to each other in a side view or in a section view, with the displacement direction of the first displacement element lying in the plane of view or the section plane. The second displacement element and the second force transmission element can also be arranged eccentrically to each other in a side view or in a section view, with the displacement direction of the second displacement element lying in the plane of view or the section plane. In the eccentric arrangement, the corresponding displacement element can have an axis that is parallel to the respective displacement direction and, in particular, coincides with the respective displacement direction.The eccentric arrangement of the force transmission element, i.e., not coaxial with the axis of the respective displacement element, allows for appropriate contact with the force receiving element. Additionally, in this case, a counter-rotating arrangement of the force transmission elements can be realized, whose range of motion can overlap axially. That is, when the force transmission elements move towards each other, they can move past each other if the displacement directions of the displacement elements are coaxial. This allows for a space-saving design in the axial direction, i.e., parallel to the direction of displacement. In particular, a displacement element and the respective force transmission element can have an L-shape in the aforementioned side view or sectional view. 2024PF00142.

[0035] 7

[0036] The respective displacement element can be designed to be essentially rotationally symmetrical to its axis. This reduces the risk of the displacement element tilting as a result of a force being applied by the pressure medium, thus preventing the displacement element from seizing during displacement or force application.

[0037] The first and / or second force transmission element is preferably arranged so that it can be displaced along a straight line that does not intersect the axis of rotation of the force receiving element. In other words, the respective straight line is oriented at an angle to the axis of rotation. By appropriately positioning the point of engagement of the respective force transmission element at a distance from the axis of rotation of the force receiving element, it can be achieved that the force transmitted from the respective force transmission element to the force receiving element at the point of engagement, together with the distance between the point of engagement and the axis of rotation acting as a lever arm, imposes a torque on the force receiving element, which then acts on the output interface.

[0038] By using multiple displacement elements, the torque that ultimately acts on the output interface, particularly as a steering parameter, can be increased, while the required installation space for additional or separately arranged displacement elements remains limited.

[0039] By using multiple displacement elements, the respective forces exerted on the force-bearing element are smaller than when using a single displacement element. This reduces the losses during the conversion of pressure acting on each displacement element into the respective force, since a comparatively small force is converted in a limited space for each displacement element or point of contact on the force-bearing element.

[0040] By using multiple displacement elements, a lower pressure level can be selected compared to steering gears with one displacement element. 2024PF00142

[0041] 8, so that losses due to the generation of high pressures in the pressure medium are reduced.

[0042] The interior of the housing can be divided into a first displacement chamber, a second displacement chamber, and a third displacement chamber by the first and second displacement elements. In particular, it can be provided that one displacement chamber, for example, the first displacement chamber, is bounded by two displacement elements. This means that the volume of this displacement chamber can be influenced by moving the first displacement element and by moving the second displacement element. In other words, by pressurizing or reducing the pressure in this displacement chamber, or by adding or removing pressure medium, a displacement of the displacement elements that bound this displacement chamber can be achieved. In this way, a compact design of the steering gear can be realized. In particular, this makes it possible to eliminate a fourth displacement chamber.Thus, an embodiment of the steering gear can be realized which has exactly three displacement spaces, formed by dividing the interior space by the first and the second displacement element.

[0043] According to one embodiment, the first displacement space borders the second and third displacement spaces. This can be realized, in particular, such that the displacement directions of the displacement elements lie on a common straight line. The first displacement space is flanked along this line by the second displacement space on the first side of the first displacement space and by the third displacement space on the second side of the first displacement space. The displacement spaces are thus arranged one behind the other along the straight line. The first displacement space is then separated along the straight line from the second displacement space and from the third displacement space by the first displacement element and the second displacement element, respectively. In this way, it is possible to achieve opposing movements of the displacement elements., that the first displacement element and the second displacement element can move towards each other when the pressure or the amount of pressure medium in the second and third displacement chamber is increased by supplying pressure medium, while the pressure 2024PF00142.

[0044] 9 or the amount of pressure medium in the first displacement chamber is reduced by the removal of pressure medium. The first displacement element and the second displacement element can move away from each other if the pressure or the amount of pressure medium in the first displacement chamber is increased by the supply of pressure medium, while the pressure or the amount of pressure medium in the second and third displacement chambers is reduced by the removal of pressure medium.

[0045] One embodiment of the steering gear, as described, for example, in the two preceding paragraphs, can be designed such that the force-receiving element is arranged in the displacement chamber, which is separated from the second displacement chamber and the third displacement chamber, respectively, by the first displacement element and the second displacement element. The force-receiving element can thus be located, for example, in the first displacement chamber. This allows the force-receiving element to be arranged within the housing in a space-saving manner. The steering gear is designed such that any displacement of the displacement elements onto the force-receiving element is limited, particularly when the displacement elements are arranged in opposite directions. This limitation can be achieved by a stop in the housing with which the first and / or the second displacement element interacts. In this way, a collision between the displacement elements and the force-receiving element is avoided.

[0046] If the force-absorbing element is located in the displacement chamber that is separated from the second displacement chamber and the third displacement chamber, respectively, by the first displacement element or the second displacement element (e.g., in the first displacement chamber), then the first force-transmitting element and / or the second force-transmitting element can also be arranged such that they are located in or extend within this displacement chamber. The first force-transmitting element can extend from a surface of the first displacement element into the displacement chamber and engage with the force-absorbing element. Alternatively or additionally, the second force-transmitting element can extend from a surface of the second displacement element into the displacement chamber and engage with the 2024PF00142

[0047] 10

[0048] The force-absorbing element is engaged. As described above, the

[0049] Displacement elements and force-absorbing elements should be arranged in an L-shape.

[0050] Such an arrangement of the force transmission elements can be provided, in particular, when the displacement elements are arranged in opposite directions. Generally, it can be provided that the force transmission elements, as described above, each exert a force on the force-receiving element at their respective point of engagement, spaced apart from the axis of rotation of the force-receiving element, thereby imposing a torque on the force-receiving element, which is summed at the force-receiving element.

[0051] The steering gear may have a first and / or a second hydraulic connection. The first and / or second hydraulic connection may be designed to supply and / or discharge hydraulic fluid from the displacement chambers. This allows for changes in the pressure or the amount of hydraulic fluid in the displacement chambers, particularly in the first, second, and third chambers. This, in turn, allows the displacement elements to be moved accordingly.

[0052] The first and / or second pressure medium connection can be designed to be connected to a pressure medium delivery unit, such as a pump. This makes it possible to supply and discharge pressure medium via the pressure medium delivery unit.

[0053] The first and / or second hydraulic fluid connection can be located inside or on the outside of the steering gear housing. This ensures easy access to the respective connections.

[0054] The first pressure medium connection can be connected to the first displacement chamber mentioned above. This means that pressure medium can be supplied or discharged via the first pressure medium connection. 2024PF00142

[0055] 11

[0056] The second pressure medium connection can be connected to the aforementioned second displacement chamber and / or the aforementioned third displacement chamber. This means that pressure medium can be supplied to or discharged from the second pressure medium connection. In an embodiment of the steering gear where the first displacement chamber is located adjacent to the second and third displacement chambers, or where the first displacement chamber is flanked by the second and third displacement chambers, the second pressure medium connection can be connected to the second and third displacement chambers to supply or discharge pressure medium into these displacement chambers, particularly simultaneously. The second pressure medium connection can be directly connected to one of the displacement chambers, while the other displacement chamber is connected to the second pressure medium connection via a suitable pipe connection.Alternatively, both the second and third displacement chambers can be connected to the second pressure medium connection via appropriate pipe connections. The design of the connection from the second pressure medium connection to the second and third displacement chambers can be adapted to the available installation space. This means that the second pressure medium connection can be positioned at a suitable location, determined, for example, by the available installation space. The connection of the second and third displacement chambers to the second pressure medium connection, regardless of whether it is a direct connection or a pipe connection, allows for the simultaneous supply and discharge of pressure medium from the second and third displacement chambers. This ensures that pressure increases and decreases in the second and third displacement chambers can occur synchronously.Furthermore, only one connection, namely the second pressure medium connection, is sufficient for supplying and removing pressure medium to and from the second and third displacement chambers.

[0057] In addition to the first and second hydraulic ports, the steering gear can also have a third hydraulic port. In such a configuration, each displacement chamber can be connected to its own hydraulic port. That is, the first displacement chamber can be connected to the first hydraulic port, the second displacement chamber to the second hydraulic port, and the third to the third. 2024PF00142

[0058] 12

[0059] The displacement chamber can be connected to the third hydraulic fluid connection. This eliminates the need for internal pipe connections within the steering gear or its housing that would, for example, connect two displacement chambers, such as the second and third, to the same hydraulic fluid connection. In particular, if the first displacement chamber is adjacent to the second and third displacement chambers, and especially if the first displacement chamber is flanked by the second and third displacement chambers, a corresponding simultaneous supply and discharge of hydraulic fluid to and from the second and third displacement chambers can be achieved via the second and third hydraulic fluid connections. In this case, a corresponding pipe connection can branch off from a hydraulic fluid supply unit to the second and third hydraulic fluid connections.This avoids separate pipe connections between the pressure medium delivery unit and the pressure medium connections.

[0060] Alternatively, separate pipe connections can be provided from the pressure medium delivery unit to the second and third pressure medium connections, which avoids a complex pipe design.

[0061] According to one embodiment, the first pressure medium connection is connected to the first displacement chamber, and the second pressure medium connection is connected to the second and third displacement chambers. As described above, this means that only one pressure medium connection is sufficient for supplying and removing pressure medium into and out of the second and third displacement chambers, respectively. Particularly when the displacement elements are arranged in opposite directions, pressure medium can be supplied to and removed from the second and third displacement chambers via a single pressure medium connection, namely the second pressure medium connection. The amount of pressure medium in the second and third displacement chambers can therefore always be adjusted to the opposing movement of the displacement elements.

[0062] According to one embodiment, the first force transmission element can be guided on an inner wall of the housing. Alternatively or additionally, the second force transmission element can be guided on an inner wall of the housing. In this way, support for the force transmission element, preferably 2024PF00142, is provided.

[0063] 13. This is achieved over the entire displacement path along the respective displacement direction. This reduces the tendency of the respective force transmission element to buckle. This allows the force transmission element to be designed in such a way that it extends essentially parallel to the displacement direction of the respective displacement element. In this way, even comparatively high forces can be reliably transmitted to the force-bearing element.

[0064] The inner housing walls that guide the first and second power transmission elements can be identical, i.e., they can be the same inner housing wall, with the power transmission elements being supported by different sections of the inner housing wall. If the axial positions of the power transmission elements overlap under certain operating conditions of the steering gear or at certain positions of the displacement elements, for example, if the steering gear has a counter-rotating arrangement of displacement elements as described above and the power transmission elements each extend into the first displacement space, it can be provided that the power transmission elements are guided by different wall sections of the first displacement space to avoid a collision of the power transmission elements.

[0065] According to one embodiment, the first displacement element and / or the first force transmission element may be mounted in the housing by means of a hydrostatic bearing. Alternatively or additionally, the second displacement element and / or the second force transmission element may be mounted in the housing by means of a hydrostatic bearing. The corresponding hydrostatic bearing may be located between the respective displacement element and / or the respective force transmission element and an inner wall of the housing, against which the respective displacement element or force transmission element moves. This may, in particular, be the inner wall of the housing described above, which is provided to support one or more of the force transmission elements. The corresponding hydrostatic bearing may extend section by section or over the entire length of the displacement element.

[0066] 14 and / or of the force transmission element in the direction of displacement form a hydrostatic support film made of a correspondingly hydrostatically acting means, which separates the displacement element and / or the force transmission element from the inner wall of the housing, resulting in a reduction of friction compared to a configuration without a corresponding support film of the elements.

[0067] To form the hydrostatic bearing, the corresponding displacement element and / or power transmission element can have a bearing cavity in which the hydrostatic agent is provided to form the hydrostatic support film. The bearing cavity can, for example, be open towards the corresponding inner wall of the housing to supply the hydrostatic agent for the formation of the support film between the inner wall of the housing and the displacement element and / or power transmission element. The bearing cavity can be supplied from a source containing the appropriate agent. The bearing cavity itself can, for example, be a recess on the corresponding displacement element and / or power transmission element. This could, for example, be a groove extending over a section of the corresponding displacement element and / or power transmission element. A corresponding geometry is, for example,can be manufactured by machining.

[0068] The hydrostatic bearing has the property that forces arising perpendicular to the respective direction of displacement of the first and / or second displacement element, e.g., from the point of contact between the respective force transmission element and the force receiving element, can be supported over as large an area as possible by the bearing film. These can be, in particular, transverse forces oriented perpendicular or transverse to the direction of displacement and which can result, for example, from the point of contact of a gear, such as a helical gear.

[0069] According to one embodiment, at least one of the hydrostatic bearings can be connected to at least one, preferably at least two, of the displacement chambers. Pressure medium can be supplied via such a connection as a hydrostatically acting means for forming the support film at the corresponding 2024PF00142

[0070] 15

[0071] The bearing cavity is conveyed. In this way, the existing pressure medium can be used to form the support film. A separate hydrostatic agent is therefore unnecessary. In particular, it is then possible to form the hydrostatic bearing within a displacement chamber, such as the first displacement chamber, since a leakage of the support film into the displacement chamber then only leads to the mixing of identical agents, namely the pressure medium and the hydrostatic agent of the support film, within the displacement chamber.

[0072] If the hydrostatic bearing is designed to be connected to two or at least two displacement chambers, the steering gear is preferably designed such that the connection to the hydrostatic bearing, in particular to the bearing cavity of the hydrostatic bearing, is always made to the displacement chamber that has the higher pressure. This ensures that the load-bearing film is built up at the highest possible pressure prevailing in the pressure medium or in the respective displacement chambers. To implement such a connection, the corresponding displacement element and / or the corresponding power transmission element can have a changeover valve that is connected to the bearing cavity and to the respective displacement chambers.For two displacement chambers that are to be connected to the bearing cavity, a double check valve connected to both displacement chambers can be used. The changeover valve or double check valve can then be designed to connect only the displacement chamber with the higher pressure to the bearing cavity. This allows pressurized fluid to flow from the connected displacement chamber to the bearing cavity, thus building up the bearing film.

[0073] According to one embodiment, the first displacement element, the second displacement element, the first force transmission element, and the second force transmission element are designed such that when the first displacement element and the second displacement element are displaced, a force couple of equal magnitude is applied to the force receiving element. In this way, a torque can be applied to the force receiving element and further to the output interface. If the forces also act in opposite directions and with the same magnitude, 2024PF00142

[0074] 16

[0075] By reducing the distance to the axis of rotation of the force-receiving element, lateral forces in the engagement points between the force-receiving element and the force-transmitting elements of a helical gear can be compensated. The gearing between the force-receiving element and the first and / or second force-transmitting element can therefore be designed with a smaller module.

[0076] According to one embodiment, the first and second displacement elements are designed to be displaceable parallel to the same direction of displacement. In particular, it can be provided that both displacement elements are displaceable in opposite directions, as described above. The first and second force transmission elements are preferably arranged point-symmetrically in a lateral sectional view of the steering gear, with the section plane of the sectional view bisecting the displacement elements and the direction of displacement lying in the section plane. This allows the force-receiving element to be subjected to the first and second forces without being affected by lateral forces. The gear teeth can be designed with a small module.

[0077] According to one embodiment, the mechanical engagement between the first force transmission element and the force receiving element can be realized via helical or swept gearing. Alternatively or additionally, the mechanical engagement between the second force transmission element and the force receiving element can be realized via helical or swept gearing. In this embodiment, the force receiving element can be supported by means of angled bearings. In the case of helical gearing, the resulting axial forces can thus be absorbed. The angled bearings can support the shaft on which the force receiving element is provided. Axial forces can thus be introduced from the helical gearing, via the force receiving element, into the shaft and further supported in at least one of the angled bearings.The bearings can be supported in the steering gear housing, which may have corresponding bearing seats. Regardless of the gearing, axially acting forces can be supported via the angled bearing arrangement, as described in 2024PF00142.

[0078] 17

[0079] Forces or moments, in particular reaction forces or reaction moments, are introduced into the steering gear via the output interface from the steering mechanism. Preferably, axially acting forces of up to 12 kN can be supported in this way. The helical gearing allows for a good meshing ratio and a more constant pressure angle compared to spur gearing.

[0080] Furthermore, the angled bearing arrangement can achieve better efficiency and / or better durability of the bearings, especially compared to corresponding plain bearings, since the preload from the angled bearing arrangement has a positive effect on the rolling of the rolling elements.

[0081] At least one bearing seat, designed to receive one of the sloping bearings, can be axially aligned with the axis of rotation of the power transmission element by means of

[0082] The spacer elements can be designed to be adjustable. This allows the axial position of the corresponding bearing seat, and thus the axial position of the corresponding bearing, to be adjusted. This enables the adjustment of play in the shaft on which the load-bearing element is mounted and / or play in the gearing between the load-bearing element and the first and / or second load-bearing element. The spacer elements can be designed as shims that can be inserted to achieve the desired axial position. The spacer elements can come into direct contact with the corresponding bearing, being positioned between the bearing and a shoulder in the housing to axially position the bearing relative to the shoulder.However, it can also be intended that the spacers are designed to axially position a housing section, such as a cover on which the bearing seat is located, by inserting at least one spacer between the rest of the housing and the housing section to separate the housing section from the rest of the housing or to adjust it into an axial position. The housing section can be attached to the housing, for example, using fasteners such as screws. This type of axial positioning or play adjustment can be implemented during the assembly of the steering gear. An adjusting screw for setting the axial position is part number 2024PF00142.

[0083] 18 is not required. High axial forces, which can cause the adjusting screw to seize or break during game adjustment, therefore do not pose a problem here.

[0084] According to one embodiment, the steering gear has a mechanical coupling designed for connection to a driver interface. A steering element, such as a steering wheel, can serve as the driver interface. The mechanical coupling can include a motion converter, such as a ball screw drive, which converts a rotary motion introduced into the mechanical coupling via the driver interface into a displacement of the first displacement element and / or the second displacement element parallel to their direction of displacement. This creates a mechanical linkage that ensures the steering gear can always generate a steering torque, even if generating a steering torque by supplying pressure fluid to displacement chambers of the steering gear and simultaneously discharging pressure fluid from other displacement chambers of the steering gear is not possible, for example, due to a defect or malfunction.The steering gear is therefore designed with redundancy. In particular, the steering gear can be designed to assist the steering input in the sense of power steering by supplying and / or removing the pressure medium into and out of the displacement chambers.

[0085] In particular, the mechanical coupling can include a shaft extending from the steering gear housing and designed to connect to the driver interface outside the housing. The driver interface can be located, in particular, at the end of the shaft extending from the housing. The other end of the shaft can be configured as a spindle, specifically for the ball screw drive of the motion converter, which is in contact with one of the displacement elements, configured as the nut of the ball screw drive of the motion converter. In this way, a rotary motion of the shaft, generated by the driver interface, can be converted into a translational displacement of the displacement element parallel to the direction of displacement, corresponding to the direction of rotation. 2024PF00142

[0086] 19

[0087] To ensure a uniform and central application of the force required to displace the corresponding displacement element, the spindle is preferably connected centrally to the displacement element. In this configuration, the spindle can extend through the displacement element, which can complicate the sealing of the displacement chambers on both sides of the displacement element. Alternatively, the spindle can be located at the level of the force transmission element of the displacement element. In this way, the spindle can extend through the displacement element and into the force transmission element, which may, for example, have a suitably shaped cavity. Thus, the spindle does not extend from a displacement chamber on one side of the displacement element to another displacement chamber on the other side, simplifying the sealing of both displacement chambers.

[0088] According to a further embodiment, the mechanical coupling, which is designed for connection to a driver interface, can be implemented via a gearbox provided outside the housing or a connection to the output interface provided outside the housing. In this way, there are no openings or penetrations in the housing through which a shaft or other elements extend into the housing from the outside, which facilitates sealing of the housing, in particular the displacement chambers.

[0089] According to another aspect, a steering unit with a steering gear as described above is provided. The steering unit may include a hydraulic control unit and / or a driver interface. The hydraulic control unit may include a hydraulic delivery unit, such as a pump, which is connected to corresponding ports on the steering gear. In this way, hydraulic fluid can be supplied from the hydraulic delivery unit to the ports on the steering gear and further to the corresponding displacement chambers. The hydraulic delivery unit may be connected directly or via a valve unit to the ports on the steering gear. The valve unit makes it possible to direct the hydraulic fluid flow supplied by the hydraulic delivery unit to the required ports and thus to the required displacement chambers in order to apply the torque to the output interface. 2024PF00142

[0090] 20

[0091] The driver interface can include a steering element, such as a steering wheel or steering lever. A driver can use this to transmit steering inputs to the steering unit. The steering element can be mechanically connected to the steering gear. Alternatively, the steering unit can be designed as a steer-by-wire unit, in which no mechanical connection is provided between the steering gear and the driver interface. In both cases, the steering unit can include a control unit designed to process steering inputs, e.g.,to detect a steering angle at the driver interface and consequently control the pressure medium delivery unit accordingly in order to provide steering assistance with existing mechanical coupling by generating a torque on the output interface as a result of the displacement of the displacement elements, or in order to realize a steering process at all as a result of the displacement of the displacement elements in the absence of mechanical coupling.

[0092] Alternatively or additionally, the steering unit can be designed to process automated steering inputs, for example in autonomous or semi-autonomous ferry operation. In this case, the corresponding steering effect can be achieved by appropriately controlling the hydraulic fluid delivery unit and thereby shifting the displacement elements.

[0093] According to a further aspect, an axle unit is provided which has a steering unit as described above and at least one steered wheel, wherein the output interface of the steering gear is connected to a steering mechanism in order to impose a torque as a steering torque via the output interface on the steering mechanism for steering the at least one steered wheel. The steering mechanism may include a tie rod of the axle unit, wherein the steering mechanism may be configured to convert the steering torque into a force on the tie rod in order to effect the steering of the at least one steered wheel.

[0094] According to another aspect, a vehicle is planned. The vehicle has a

[0095] Steering unit as described above or axle unit as described above. 2024PF00142

[0096] 21

[0097] The vehicle can be designed specifically as a commercial vehicle or truck. The steering or axle unit offers the advantage that steering can be performed or assisted by the hydraulic actuation of the displacement elements, thereby overcoming high wheel contact forces in conjunction with the comparatively high vehicle weight.

[0098] Exemplary embodiments of the present disclosure are described below with reference to the accompanying drawings.

[0099] They show:

[0100] Fig. 1 shows a schematic and exemplary sectional view of a steering gear from a first viewing direction.

[0101] Fig. 2 shows a schematic and exemplary sectional view of the steering gear from Fig. 1 from a second viewing direction.

[0102] Fig. 3 shows a schematic embodiment of an axle unit,

[0103] Fig. 4 shows a schematic embodiment of a second axle unit,

[0104] Fig. 5 shows a schematic embodiment of a steering unit,

[0105] Fig. 6 shows a schematic embodiment of another steering unit, and

[0106] Fig. 7 shows a schematic embodiment of a vehicle.

[0107] Fig. 1 shows a schematic and exemplary sectional view of a steering gear from a first perspective, and Fig. 2 shows a schematic and exemplary sectional view of the steering gear from Fig. 1 from a second perspective. The section path of Fig. 2 is labeled AA in Fig. 1. The steering gear is described below with reference to both drawings. 2024PF00142

[0108] 22

[0109] A steering gear 1 is shown, which has a housing 2. The housing 2 extends in the horizontal direction in the displacement direction X.

[0110] Within the housing 2, or in an interior space of the housing 2, a first displacement element 10 and a second displacement element 11 are arranged. The displacement elements 10 and 11 are provided to slide parallel to the direction of displacement X in the housing 2.

[0111] The displacement elements 10, 11 divide the interior of the housing 2 into three displacement chambers 3, 4, 5, which are arranged from left to right in the following order: third displacement chamber 5, first displacement chamber 3 and second displacement chamber 4. That is, the first displacement chamber 3 is flanked along the displacement direction X by the third displacement chamber 5 and by the second displacement chamber 4.

[0112] The first displacement element 10 has a sealing element 16 on its circumference that interacts with the inner wall of the housing 15, thereby sealing the first displacement chamber 3 against the second displacement chamber 4. The second displacement element 11 has a sealing element 17 on its circumference that interacts with the inner wall of the housing 15, thereby sealing the first displacement chamber 3 against the third displacement chamber 5.

[0113] The displacement elements 10, 11 are designed here as pistons which are displaceable parallel to the displacement direction X as a result of a supply or discharge of pressure medium into the displacement spaces 3, 4, 5.

[0114] The first displacement element 10 has a first force transmission element 12 on a side facing the first displacement chamber 3. This element has engagement elements in the form of a toothing 27 and extends essentially parallel to the displacement direction X.

[0115] The second displacement element 11 has a second force transmission element 13 on a side facing the first displacement chamber 3. This element has 2024PF00142

[0116] 23

[0117] The engagement elements are in the form of a toothing 28 and are essentially parallel to the displacement direction X.

[0118] Both power transmission elements 12, 13 are designed here as rack and pinion elements.

[0119] Displacement element 11 and force transmission element 13 are not shown in Fig. 2 for the sake of clarity.

[0120] Within the first displacement chamber 3, a force-receiving element 9, designed as an externally and helically toothed gear, is arranged and rotatably mounted about a pivot axis 14. An output interface 30 is coupled to the force-receiving element 9; this output interface 30 is configured here as a coupling section of a shaft 29, in particular a segmented shaft, rotatable about the pivot axis 14. The output interface 30 can be configured to transmit torque or steering torque, in particular as a steering input, to a steering unit.

[0121] The housing 2 has a first pressure medium connection 6 and a second pressure medium connection 7. The first pressure medium connection 6 opens into the first displacement chamber 3, while the second pressure medium connection 7 opens into the second displacement chamber 4. Additionally, a connecting line 8 extends from the second pressure medium connection 7 through the wall of the housing 2 to the third displacement chamber 5. This allows pressure medium, such as hydraulic fluid, to be supplied to or discharged from the second pressure medium connection 7 to both the second displacement chamber 4 and the third displacement chamber 5. The supply and discharge of pressure medium to and from the first displacement chamber 3 can be carried out via the first pressure medium connection 6.

[0122] The force transmission elements 12, 13 are in contact with engagement elements in the form of a toothing 26 of the force receiving element 9 via their respective toothing 27, 28. When the displacement elements 10, 11 are displaced and the force transmission elements 12, 13 are thereby displaced, a force can be applied to the 2024PF00142 via the point of engagement or contact between the toothing 26 and 27 or 26 and 28.

[0123] 24

[0124] Force-absorbing element 9 is pressed onto the shaft. Due to the offset of the engagement points to the axis of rotation 14, a torque acts on the force-absorbing element 9. The shaft 29 then transmits this torque, which represents, for example, the steering input, to the output interface 30.

[0125] To achieve this force transmission to the force-receiving element 9, the displacement elements 10 and 11 are designed to rotate in opposite directions. This is accomplished by connecting the second displacement chamber 4 and the third displacement chamber 5 to the second pressure medium connection 7 and by connecting the first pressure medium connection 6 to the first displacement chamber 3. For example, supplying pressure medium to the first displacement chamber 3 via the first pressure medium connection 6 and simultaneously discharging pressure medium from the second displacement chamber 4 and the third displacement chamber 5 via the second pressure medium connection 7 can cause the displacement elements 10 and 11 to move away from each other. That is, in Fig. 1, the first displacement element 10 moves in the displacement direction X, while the second displacement element 11 moves in the opposite direction to the displacement direction X. The engagement of the gears 26 and 27, respectively, is achieved accordingly.26, 28 a clockwise torque or a clockwise rotational movement in Fig. 1 is applied to the force-receiving element 9 and ultimately to the output interface 30 via the shaft 29. In the reverse case, i.e., when pressure medium is supplied to the second displacement chamber 4 and the third displacement chamber 5 via the second pressure medium connection 7 while pressure medium is simultaneously discharged from the first displacement chamber 3 via the first pressure medium connection 6, a reverse movement begins, i.e., the displacement elements 10, 11 now move towards each other. That is, the first displacement element 10 moves against the direction of displacement X and the second displacement element 11 moves in the direction of displacement X. As shown in Fig.As can be seen in Figure 1, the force transmission elements 12 and 13 are arranged for this opposing movement such that they overlap in the direction of displacement X. However, the first force transmission element 12 is located at the top of the drawing, and the second force transmission element 13 is located at the bottom. In this way, both elements 12 and 13 can move past each other. In this case, reference is made to 2024PF00142.

[0126] 25

[0127] Force receiving element 9 is subjected to a counterclockwise torque in Fig. 1 or a counterclockwise rotational movement in Fig. 1.

[0128] To guide the force transmission elements 12 and 13 within the first displacement chamber 3 without collision, the first displacement element 10 forms an L-shape with the first force transmission element 12 in the sectional view, as shown in Fig. 1. The second displacement element 11 also forms an L-shape with the second force transmission element 13. Both L-shapes are arranged so that they can move in opposite directions without collision.

[0129] The arrangement of the force receiving element 9 and the force transmission elements 12, 13 makes it possible to implement the steering gear 1 in a space-saving manner.

[0130] By arranging the displacement elements 10, 11 in the same housing 2 and by subdividing the housing 2 into displacement chambers 3, 4, 5, whereby pressure medium in the first displacement chamber 3 can exert pressure on both displacement elements 10, 11, a space-saving and less complex embodiment of the steering gear 1 is created. In particular, this embodiment eliminates the need for a fourth displacement chamber, which results in significant space advantages compared to an embodiment that has four displacement chambers for pressurizing two displacement elements, i.e., a separate displacement chamber for pressurizing each side of the displacement elements.

[0131] Figure 1 further shows that the first force transmission element 12 and the second force transmission element 13 are guided on the inner wall 15 of the housing. In this way, the buckling tendency of the elements 12, 13 can be reduced by supporting the inner wall 15 under high forces acting parallel to the direction of displacement X. As can be seen in Figure 2, the housing 2, or rather the interior of the housing 2, is essentially cylindrical along the direction of displacement X. The force transmission elements 12, 13 conform to the curvature of the inner wall 15 resulting from the cylindrical shape, according to 2024PF00142.

[0132] 26 adapted so that the rounded shape provides further stabilization of the power transmission elements 12, 13.

[0133] The steering gear 1 has an optional mechanical coupling 40. The mechanical coupling 40 has a mechanical interface 41, which is designed as a shaft rotatable about a pivot axis 42 and is configured to be connected to a driver interface, such as a steering element, e.g., a steering wheel. A driver can input steering commands to the steering gear 1 via this interface. In Fig. 1, the shaft of the mechanical coupling 40 extends from the right through the wall of the housing 2, through the second displacement chamber 4, and through the first displacement element 10 into the first displacement chamber 3. The shaft is supported in the housing 2 by means of a bearing 43, with the bearing 43 and the housing being appropriately sealed at the location of the bearing 43 to seal the second displacement chamber from the environment of the housing 2. The mechanical coupling 40 has a motion converter 44, which is designed here as a ball screw drive.The left-hand section of the shaft in the drawing is designed as the spindle of the ball screw drive, while the first displacement element 10 is designed as, or incorporates, the nut of the ball screw drive. A rotational movement of the shaft, for example, corresponding to a steering input from the driver, thus causes a corresponding displacement of the first displacement element 10 in the direction of displacement X or against the direction of displacement X. This displacement of the first displacement element 10 transmits force via the first force transmission element 12 to the force receiving element 9, thereby imposing a torque on the force receiving element 9 and ultimately on the output interface 30. Thus, steering can be achieved through the mechanical coupling 40. This provides a mechanical through-drive from the driver interface to the steering gear 1 and thus to the output interface 30.

[0134] The output interface 30 extends to the left from the housing 2 in the drawing in Fig. 2 and is configured to be connected to a steering mechanism in order to transmit the steering torque to the steering mechanism. 2024PF00142

[0135] 27

[0136] As can be seen in Fig. 2, the toothing 26 is chamfered. This allows for backlash compensation of the shaft 29 along the axis 14 and improved force transmission to the force receiving element 9, which ultimately leads to improved operating characteristics and reduced noise emissions of the steering gear.

[0137] As shown in Fig. 2, the shaft 29 is supported by means of an angled bearing arrangement with bearings 31, 32, which are designed here as tapered roller bearings. Alternatively, for example, an angled ball bearing arrangement could also be provided. The angled bearing arrangement serves to absorb axial and radial forces resulting from the contact of the gear teeth 26 with the gear teeth 27, 28 of the power transmission elements 12, 13.

[0138] The bearings 31 and 32 are located outside the interior of the housing 2, which is divided into three displacement chambers 3, 4, and 5. This allows the bearings 31 and 32 to be mounted on the steering gear 1.

[0139] The left bearing 31 is axially fixed to the housing 2 by means of a locking element 36, which here is designed as an axially mounted ring.

[0140] The interior of the housing 2, which is divided into the three displacement chambers 3, 4, 5, is sealed in the direction of the axis 14 by sealing elements 33, 34, which are in contact with the outer surface of the shaft 29 as sliding sealing elements. The sealing element 34 is axially fixed by a retaining element 37 designed as a circlip.

[0141] The right-hand bearing 32 is provided in a cover 38 of the housing 2, which closes off the interior of the housing 2 to the right. For this purpose, the cover 38 has a sealing element 35 that is in contact with the housing 2. Alternatively, the sealing element 35 can also be provided separately.

[0142] The axial position of the cover 38 with respect to the axis 14 can be adjusted in the embodiment of the steering gear 1 shown here. Thus, the axial position of the bearing 32 or the axial position of the corresponding bearing seat can also be adjusted. The adjustment of the axial position can be achieved by spacers 47, such as shims, which are placed between the cover 2024PF00142

[0143] 28

[0144] The cover 38 and housing 2 are inserted. In this way, the axial position of the force transmission element 9 and ultimately the clearance in the engagement of the gears 26, 27 or 26, 28 can be adjusted. The cover 38 can then be connected to the housing 2 by means of fastening elements 39, such as screws. Such an adjustment of the axial position has the advantage that no axial forces need to be overcome, as is the case, for example, with an adjusting screw. Instead, the axial position is already set during assembly by the corresponding axial distance between the cover 38 and the housing 2, which is achieved by the spacer elements 47. There is no risk of an axial adjusting screw seizing or breaking due to high axial forces.

[0145] Furthermore, Fig. 1 shows that the first power transmission element 12 is supported by a hydrostatic bearing 45, which forms a hydrostatic support film between the first power transmission element 12 and the inner wall 15 of the housing. The hydrostatic bearing 45 has a bearing cavity 18 through which the support film is supplied. The hydrostatic bearing 45 has a bearing supply line 20 that opens into the first displacement chamber 3 and the second displacement chamber 4. A valve 22 is provided in the bearing supply line 20, which here is designed as a changeover valve, e.g., a double check valve. The valve 22 is designed to connect the bearing cavity 18 via the line 24 to the displacement chamber 3, 4, in which the higher pressure prevails. Thus, pressure medium for the formation of the support film can be conveyed to the bearing cavity 18, which is already provided in the interior of the housing 2.The formation of the support film thus enables displacement of the first displacement element 10 both in the direction of displacement X and against the direction of displacement X. The support film between the first force transmission element 12 serves to reduce friction between the first force transmission element 12 and the inner housing wall 15 and to support forces generated by the engagement of the gears 26, 27.

[0146] Furthermore, Fig. 1 shows that the second power transmission element 13 is supported by a hydrostatic bearing 46, which forms a hydrostatic support film between the second power transmission element 13 and the inner wall 15 of the housing. The hydrostatic bearing 46 has a bearing cavity 19 through which the support film 2024PF00142

[0147] The hydrostatic bearing 46 is supplied by a bearing supply line 21, which opens into the first displacement chamber 3 and the third displacement chamber 5. A valve 23, designed here as a changeover valve, e.g., a double check valve, is provided in the bearing supply line 21. The valve 23 is designed to connect the bearing cavity 19 via the line 25 to the displacement chamber 3, 5, where the higher pressure prevails. This allows pressure medium to be supplied to the bearing cavity 19, which is already provided in the interior of the housing 2, to form the support film. The formation of the support film is thus possible both for a displacement of the second displacement element 11 in the direction of displacement X and against the direction of displacement X.The supporting film between the second power transmission element 13 serves to reduce friction between the second power transmission element 13 and the inner housing wall 15 and to support forces generated by the engagement of the gear teeth 26, 28.

[0148] Fig. 3 shows a schematic embodiment of an axle unit.

[0149] An axle unit 100 is shown. The axle unit 100 has a steering unit 50 according to the present disclosure and a steered vehicle axle on which steered wheels 101 are provided on both sides of a longitudinal axis 201, which can be steered via an indicated steering mechanism 102.

[0150] The steering unit 50 has a steering gear 1, which corresponds to the steering gear 1 shown in Figures 1 and 2; therefore, reference is made to these figures below. The steering gear 1 has a first hydraulic connection 6 and a second hydraulic connection 7, wherein a steering torque can be generated in the interior of the housing 2 of the steering gear 1 by supplying and discharging hydraulic fluid via the hydraulic connections 6 and 7. This torque acts on the steering mechanism 102, which is connected to the output interface 30 of the steering gear 1 shown in Figure 2. In this way, the wheels 101 can be steered.

[0151] The steering unit 50 includes a pressure medium control unit 60 for controlling the pressure medium supply and discharge. 2024PF00142

[0152] 30

[0153] The pressure medium control unit 60 comprises a pressure medium delivery unit 51, which is designed as a pump to deliver pressure medium from a pressure medium reservoir 58 via a suction line 56 and through a line 52 to a valve unit 53. The valve unit 53 of the pressure medium control unit 60 is shown here as a box and can have different configurations. As shown, it can be structurally designed as a single unit in which corresponding valves for controlling the pressure medium flow are provided. Alternatively, it can also be designed as a combination of individual valves that control the pressure medium flow and are not combined into a single structural unit. Ultimately, the valve unit 53 shown here represents different designs for controlling the pressure medium flow.

[0154] The valve unit 53 is connected to the pressure medium supply unit 51 via line 52, allowing pressure medium to be supplied to the valve unit 53. Furthermore, the valve unit 53 is connected to the first pressure medium port 6 via a first pressure medium supply line 54 and to the second pressure medium port 7 via a second pressure medium supply line 55. Finally, the valve unit 53 is connected to the pressure medium reservoir 58 via a return line 57, allowing pressure medium to be supplied back to the pressure medium reservoir 58.

[0155] Furthermore, the steering unit 50 has a driver interface 59, which can be designed, for example, as a steering element such as a steering wheel. The drawing does not show a connection between the driver interface 59 and the steering gear 1. This means that there is no mechanical connection. The steering unit 50 can therefore be a steer-by-wire steering system, in which signals, such as a steering input at the driver interface 59, e.g., a steering angle, are detected and processed by a control unit (not shown) of the steering unit 50. The control unit is then designed to actuate the hydraulic fluid delivery unit 51 and / or the valve unit 53 accordingly in order to control the hydraulic fluid flow to and from the hydraulic fluid connections 6, 7. 2024PF00142

[0156] 31

[0157] The steering unit 50 is thus designed to process steering inputs from a driver via the driver interface 59 and to generate a corresponding steering torque through the steering gear 1 and to impose it on the steering mechanism 102 for steering the wheels 101, whereby pressure medium is supplied to the first pressure medium port 6 by the pressure medium control unit 60, while pressure medium is discharged from the second pressure medium port 7, or wherein pressure medium is discharged from the first pressure medium port 6 by the pressure medium control unit 60, while pressure medium is supplied to the second pressure medium port 7.

[0158] Fig. 4 shows a schematic embodiment of a second axle unit.

[0159] In contrast to the embodiment shown in Fig. 3, here a mechanical interface 41, as shown in Fig. 1, leads to the driver interface 59. Thus, a mechanical connection exists from the driver interface 59 to the steering gear 1, via which, at least in the event of a failure of the pressure medium control unit 60, a steering torque can still be applied by the steering gear 1 to the steering mechanism 102 for steering the wheels 101.

[0160] Another embodiment of an axle unit 100 or a steering unit 50, not shown, has a mechanical connection from the driver interface 59 to the valve unit 53. In this case, the valve unit 53 is designed to be mechanically controlled from the driver interface 59. This means that the supply of pressure medium to the first pressure medium port 6 and the discharge of pressure medium from the second pressure medium port 7, or the discharge of pressure medium from the first pressure medium port 6 and the supply of pressure medium to the second pressure medium port 7, can be achieved by mechanically adjusting the valve unit 53.

[0161] All embodiments of the steering units 50, which have a mechanical drive from a driver interface to the steering gear, e.g. via the mechanical interface 41, can be designed such that the valve unit 53 is switched to a flow position to allow pressure medium to pass through as a result of the 2024PF00142

[0162] 32

[0163] The movement of the displacement elements 10, 11 is to circulate freely into the displacement chambers 3, 4, 5 via the lines 54, 55 and the valve unit 53, in order to prevent the steering gear 1 from being blocked due to a pressure medium volume that cannot be displaced by a closed valve.

[0164] Fig. 5 shows a schematic embodiment of a steering unit.

[0165] A steering unit 50 is shown, which includes a pressure medium control unit 60. The pressure medium control unit 60 comprises a pressure medium delivery unit 51, which can deliver pressure medium from a pressure medium reservoir 58 via a suction line 56. The pressure medium delivery unit 51 can, for example, be driven by drive motors 80 of a vehicle (not shown) in which the steering unit 50 is provided. Depending on the vehicle concept, a combustion engine 81 and / or an electric drive motor 82 can be used as drive motors 80. This is only an example and is not intended to exclude other drive types for the pressure medium delivery unit 51.

[0166] The pressure medium control unit 60 further comprises a valve unit 53. This valve unit is designed as a valve unit and is connected to a driver interface 59 via a mechanical connection 67. Through the driver interface 59, which can be designed, for example, as a steering element such as a steering wheel, a control movement can be applied via the mechanical connection 67 to a control element 61, which is guided inside the valve unit 53, more precisely in a housing 62 of the valve unit 53. In the case shown, the control element 61 is designed as a rotary valve element, which can be controlled according to a rotation of the steering element, which can be applied, for example, by a driver.

[0167] Valve unit 53 has ports 63, 64, 65, 66 and ports 68, 69. Port 68 is connected to a line 52, which is connected to the pressure medium delivery unit 51, and through which pressure medium can be delivered to port 68 and thus to valve unit 53. Port 69 is connected to a return line 57, through which pressure medium is returned from valve unit 53 to pressure medium reservoir 2024PF00142.

[0168] 33

[0169] 58 can be returned. The return line 57 can include further elements, such as a pressure medium cooler and a filter.

[0170] The ports 63, 64 of the valve unit 53 are connected via a first pressure medium supply line 54 to the first pressure medium port 6 of a steering gear 1, while the ports 65, 66 of the valve unit 53 are connected via a second pressure medium supply line 55 to the second pressure medium port 7 of the steering gear 1.

[0171] The steering gear 1 can be designed like the steering gear 1 shown in Figures 1 and 2.

[0172] The steering unit 50 shown is in a state in which the control element 61 of the valve unit 53 has been set by the driver interface 59 such that the port 68 is connected to the ports 63 and 64. In this way, hydraulic fluid can be conveyed via line 52 through the hydraulic fluid delivery unit 51, via the valve unit 53, and further via the hydraulic fluid supply line 54 to the first hydraulic fluid port 6 of the steering gear 1. Simultaneously, a connection exists via the second pressure medium supply line 55 from the second pressure medium port 7 of the steering gear 1 to the valve unit 53, more precisely, to ports 65 and 66. With the control element 61 in the position shown, ports 65 and 66 are connected to port 69 of the valve unit 53, so that pressure medium can be returned from the second pressure medium port 7 via the valve unit 53 to the return line 57 and thus to the pressure medium reservoir 58.In this way, the displacement elements in the steering gear 1 can be moved accordingly by the supply and discharge of the pressure medium, thereby setting the output interface 30 into rotation, which causes a lever arm 90 connected to the output interface 30 to pivot in the manner indicated by the double arrow. The lever arm 90 can be connected to a steering mechanism or already be part of a steering mechanism, in which case the steering mechanism is steered by the pivoting movement of the lever arm 90.

[0173] If the driver changes the steering angle at the driver interface 59, the

[0174] Change the switching state in valve unit 53 so that the connections 65 and 66 are then 2024PF00142

[0175] Connections 34 are connected to port 68, and ports 63 and 64 are connected to port 69. In this case, the flow direction of the pressure medium is reversed, i.e., pressure medium is then supplied to the second pressure medium port 7, while at the same time pressure medium is discharged from the first pressure medium port 6.

[0176] Finally, a locking position can be set in the valve unit 53, in which all connections 63, 64, 65, 66, 68, 69 are closed off from each other, so that no pressure medium is supplied or discharged. This corresponds, for example, to the vehicle driving straight ahead.

[0177] Furthermore, the driver interface 59 is mechanically connected via a torsion spring 48 to a mechanical interface 41 of the steering gear 1. In this way, the displacement elements within the steering gear 1 can be moved mechanically, and in particular in the event of a failure of the pressure medium control unit 60, so that steering via the driver interface 59 is possible even if the pressure medium control unit 60 fails.

[0178] Fig. 6 shows a schematic embodiment of another steering unit.

[0179] A steering unit 50 is shown, which includes a pressure medium control unit 60. The pressure medium control unit 60 includes a control unit 70, e.g., an electronic control unit. The control unit 70 is connected to an electric drive motor 82 via a control link 72, so that control signals from the control unit 70 can be sent to the drive motor 82.

[0180] The steering unit 50 has a driver interface 59, which is connected via a mechanical connection 67 and a torsion spring 48 to a mechanical interface 41 of a steering gear 1. The steering gear 1 can be designed like the steering gear from Fig. 5 and, in particular, like the steering gear 1 from Figures 1 and 2. It has a lever arm 90 connected to an output interface 30, which can be pivoted according to the double arrow shown, depending on how pressure medium is supplied to the first pressure medium connection 6 and the second 2024PF00142

[0181] 35

[0182] Pressure medium is supplied to or discharged via connection 7. The lever arm 90 can be connected to a steering mechanism, or already be part of a steering mechanism, whereby the steering mechanism is steered by the pivoting movement of the lever arm 90.

[0183] Furthermore, a pressure medium delivery unit 51 is shown, which can be operated bidirectionally by the electric drive motor 82, so that, on the one hand, pressure medium can be delivered from the pressure medium delivery unit 51 via a first pressure medium supply line 54 to the first pressure medium connection 6 of the steering gear 1, while simultaneously, pressure medium can be discharged from the second pressure medium connection 7 of the steering gear 1 via the pressure medium supply line 55 to the pressure medium delivery unit 51. In this case, a pressure medium reservoir is not required and the pressure medium control unit 60 represents a closed system.

[0184] The torsion spring 48 is further equipped with an input parameter 49, which is designed, for example, as a steering angle sensor. The input parameter 49 can detect an input parameter, such as the steering angle generated by a driver at the driver interface 59, and transmit it to the control unit 70 via a data connection 71. The control unit 70 is designed to generate a corresponding control command from the detected input parameter, which it then uses to control the electric motor 82. In this way, pressure medium can be supplied to or discharged from the connections 6 and 7 of the steering gear 1, resulting in a pivoting movement of the lever arm and thus steering of a vehicle in which the steering unit is installed. If no input parameter is generated via the driver interface 59, or if the input parameter 49 is not detected, the steering mechanism 70 is not activated.If the input value corresponds to a straight-ahead journey, the control unit can send a control command to the electric machine 82, which stops the operation of the electric machine 82, so that no more pressure medium is supplied.

[0185] This embodiment also includes a mechanical backup, as the steering movement or steering input can also be transmitted mechanically via interface 41 to the steering gear 1 and thus to the displacement elements of the steering gear. 2024PF00142

[0186] 36

[0187] Fig. 7 shows a schematic embodiment of a vehicle.

[0188] A vehicle 200 is shown in a schematic top view. The vehicle 200 has a longitudinal axis 201 that is identical to the longitudinal axis of the axle unit 100, wherein an axle unit 100, as shown in Figures 3 or 4, is shown with steered wheels 101 and a steering mechanism 102, the steering mechanism 102 being connected to the output interface 30 of the steering gear of the steering unit 50 for steering the wheels 101. The vehicle 200 may have one or more further axles 202 with non-steered wheels 203 located on both sides of the longitudinal axis 201.

[0189] The vehicle 200 can be designed as a commercial vehicle, in particular as a truck.

[0190] According to further embodiments not shown, the axle unit 100 can also have a steering unit 50 according to Fig. 5 or 6.

[0191] 2024PF00142

[0192] 37

[0193] REFERENCE MARK LIST

[0194] 1 Steering gear

[0195] 2 cases

[0196] 3 first displacement chamber

[0197] 4 second displacement chamber

[0198] 5 third displacement space

[0199] 6 first pressure medium connection

[0200] 7 second pressure medium connection

[0201] 8 connecting line

[0202] 9 Force absorption element

[0203] 10 first displacement element

[0204] 11 second displacement element

[0205] 12 first power transmission element

[0206] 13 second power transmission element

[0207] 14 axis of rotation

[0208] 15 Inner wall of the housing

[0209] 16 Sealing element

[0210] 17 Sealing element

[0211] 18 storage cavity

[0212] 19 storage cavity

[0213] 20 Warehouse supply line

[0214] 21 Warehouse supply line

[0215] 22 valve

[0216] 23 Valve

[0217] 24 lines

[0218] 25 Management

[0219] 26 gear teeth

[0220] 27 Gearing

[0221] 28 gear teeth

[0222] 29th wave

[0223] 30 Output interface

[0224] 31 bearings 2024PF00142

[0225] 38

[0226] 32 storage areas

[0227] 33 Sealing element

[0228] 34 Sealing element

[0229] 35 Sealing element

[0230] 36 locking element

[0231] 37 Safety element

[0232] 38 lids

[0233] 39 Fastening element

[0234] 40 mechanical coupling

[0235] 41 mechanical interface

[0236] 42 Rotation axis

[0237] 43 warehouses

[0238] 44 motion converters

[0239] 45 first hydrostatic bearing

[0240] 46 second hydrostatic bearing

[0241] 47 Spacer element

[0242] 48 Torsion spring

[0243] 49 Input parameter acquisition

[0244] 50 steering unit

[0245] 51 Pressure center Iförde inhe it

[0246] 52 Line

[0247] 53 Valve unit

[0248] 54 first pressure medium supply line

[0249] 55 second pressure medium supply line

[0250] 56 Intake pipe

[0251] 57 Return line

[0252] 58 Pressure medium reservoir

[0253] 59 Driver interface

[0254] 60 Pressure medium control unit

[0255] 61 Control element

[0256] 62 cases

[0257] 63 connection

[0258] 64 connection 2024PF00142

[0259] 39

[0260] 65 connection

[0261] 66 connection

[0262] 67 mechanical connection

[0263] 70 Control unit 71 Data connection

[0264] 72 Control connection

[0265] 80 drive motors

[0266] 81 Internal combustion engine

[0267] 82 electric drive motor 90 lever arm

[0268] 100 axle units

[0269] 101 steered wheel

[0270] 102 Steering mechanism

[0271] 200 Vehicle 201 (Vehicle) longitudinal axis

[0272] 202 vehicle axle

[0273] 203 wheel

[0274] X direction of displacement

Claims

2024PF00142 40 PATENT CLAIMS 1. Steering gear (1) for a vehicle (200) comprising: - a case (2); - a first displacement element (10); - a second displacement element (11 ); - a force-absorbing element (9); - an output interface (30), wherein the first displacement element (10) and the second displacement element (11) are provided in an interior of the housing (2) and divide the interior into displacement chambers (3, 4, 5), wherein the first displacement element (10) and the second displacement element (11) are provided to be displaceable, wherein the first displacement element (10) has a first force transmission element (12) and the second displacement element (11) has a second force transmission element (13), wherein the first force transmission element (12) is mechanically engaged with the force receiving element (9) and wherein the second force transmission element (13) is mechanically engaged with the force receiving element (9), wherein the force receiving element (9) is provided to be rotatable about a pivot axis (14) and is mechanically coupled to the output interface (30), wherein the steering gear (1) is designed tothat the first displacement element (10) and the second displacement element (11) can be displaced by supplying and / or removing pressure medium into at least one of the displacement chambers (3, 4, 5) and / or out of at least one of the displacement chambers (3, 4, 5), so that a first force effect is exerted on the force-receiving element (9) via the engagement between the force-receiving element (9) and the first force-transmission element (12), and a second force effect is exerted on the force-receiving element (9) via the engagement between the force-receiving element (9) and the second force-transmission element (13), wherein, 2024PF00142 41 through the first and second force action on the force receiving element (9) via the mechanical coupling of the force receiving element (9) with the output interface (30) a torque is imposed on the output interface (30).

2. Steering gear (1 ) according to claim 1, wherein the interior of the housing (2) is divided by the first displacement element (10) and the second displacement element (11 ) into a first displacement space (3), a second displacement space (4) and a third displacement space (5), and the first displacement space (3) adjoins the second displacement space (4) and the third displacement space (5).

3. Steering gear (1) according to one of the preceding claims, comprising: - a first pressure medium connection (6) and a second pressure medium connection (7) for supplying and removing pressure medium from the displacement chambers (3, 4, 5).

4. Steering gear (1) according to claims 2 and 3, wherein the first pressure medium connection (6) is connected to the first displacement chamber (3) and the second pressure medium connection (7) is connected to the second displacement chamber (4) and the third displacement chamber (5).

5. Steering gear (1) according to one of the preceding claims, wherein the first power transmission element (12) and / or the second power transmission element (13) are each guided on an inner housing wall (15) of the housing (2).

6. Steering gear (1) according to one of the preceding claims, wherein the first displacement element (10) or the first power transmission element (12) is mounted in the housing (2) by means of a hydrostatic bearing (45) and / or wherein the second displacement element (11) or the second power transmission element (13) is mounted in the housing (2) by means of a hydrostatic bearing (46).

7. Steering gear (1) according to claim 6, wherein 2024PF00142 42 at least one of the hydrostatic bearings (45, 46) can be connected to at least one of the displacement spaces (3, 4, 5).

8. Steering gear (1 ) according to one of the preceding claims, wherein the first displacement element (10), the second displacement element (11 ), the first force transmission element (12) and the second force transmission element (13) are designed such that when the first displacement element (10) and the second displacement element (11 ) are displaced, a force couple of equal magnitude is imposed on the force receiving element (9).

9. Steering gear (1 ) according to one of the preceding claims, wherein the first displacement element (10) and the second displacement element (11 ) are designed to be displaceable parallel to the same direction of displacement (X).

10. Steering gear (1) according to one of the preceding claims, wherein the mechanical engagement between the first power transmission element (12) with the power receiving element (9) is realized via a helical gear or a swept gear, and / or wherein the mechanical engagement between the second power transmission element (13) with the power receiving element (9) is realized via a helical gear or a swept gear, wherein the power receiving element (9) is mounted by means of angled bearings (31, 32).

11. Steering gear (1) according to claim 10, wherein a bearing seat designed to receive one of the oriented bearings (31, 32) is designed to be adjustable axially to the axis of rotation (14) by means of spacer elements (47).

12. Steering gear (1 ) according to one of the preceding claims, comprising a mechanical coupling (40) designed for connection with a driver interface (59).

13. Steering unit (50) comprising a steering gear (1) according to one of claims 1 to 12 and a pressure medium control unit (60) and / or a driver interface (59). 2024PF00142 43 14. Axle unit (100) comprising a steering unit (50) according to claim 13 and at least one steered wheel (101), wherein the output interface (30) of the steering gear (1 ) is connected to a steering mechanism (102) to impose a steering torque via the output interface (30) on the steering mechanism (102) for steering the at least one steered wheel (101 ).

15. Vehicle (200) comprising a steering unit (50) according to claim 13 or an axle unit (100) according to claim 14.

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