Steering device with worm gear

Abstract

This invention relates to a steering device with a worm gear transmission, the worm gear transmission having a worm shaft and a worm wheel acting with the worm shaft, wherein a first end of the worm shaft is rotatably supported in a first bearing, and a second end of the worm shaft opposite to the first end is rotatably supported in a second bearing; and the steering device has a preload device, wherein a predetermined force is applied to the worm shaft toward the worm wheel by means of the preload device, and the preload device has a first annular element having at least one elastic spring element, wherein a predetermined force for pressing and / or pulling the worm shaft onto the worm wheel is generated by means of at least one elastic spring element. To simplify the structure, construction, and / or assembly of the preload device, the steering device is characterized in that at least one elastic spring element extends inwardly from the first annular element.

Description

[0001] This invention relates to a steering device with a worm gear transmission, the worm gear transmission having a worm shaft and a worm wheel acting with the worm shaft, wherein a first end of the worm shaft is rotatably supported in a first bearing, and a second end of the worm shaft opposite to the first end is rotatably supported in a second bearing, and the second end of the worm shaft is assigned a drive connected to the worm shaft in a force-transmitting manner to rotate the worm shaft about its longitudinal axis; and the steering device has a preload device, wherein by means of the preload device, a predetermined force is applied to the worm shaft toward the worm wheel, and the preload device has a first annular element having at least one elastic spring element, wherein by means of the at least one elastic spring element, a predetermined force is generated for pressing and / or pulling the worm shaft onto the worm wheel.

[0002] One such steering device is known from EP 2 842 835 A1.

[0003] It is known that in steering systems with worm gear drives, undesirable backlash may occur between the worm shaft and the worm wheel due to wear and / or aging. To compensate for this backlash and / or avoid undesirable interference noise (especially clicking noise between the worm shaft and the worm wheel) during steering system operation, a preload device can be used to pull and / or press the worm shaft towards the worm wheel so that it works in conjunction with the worm wheel. Here, the preload device should be designed and / or integrated into the steering system such that, in addition to the desired functionality, the required space is minimized and / or the structure and / or assembly is simplified as much as possible.

[0004] The objective of this invention is to improve a steering device of the type described at the outset by simplifying and / or improving the structure, design, and / or assembly of the pretensioning device. Alternative embodiments are particularly intended to be provided.

[0005] The objective of this invention is achieved by a steering device. Preferred improvements to the invention are described below.

[0006] The steering system has a worm gear drive. In particular, the steering system is designed for use in vehicles or motor vehicles. The steering system is preferably designed as an electric servo steering system. The worm gear drive has a worm shaft and a worm wheel that interacts with the worm shaft. Specifically, the teeth of the worm shaft engage with correspondingly designed teeth of the worm wheel so that the worm shaft and worm wheel interact. Specifically, the longitudinal axis of the worm shaft is arranged laterally or perpendicularly to the axis of rotation of the worm wheel. Furthermore, a first end of the worm shaft is supported in a first bearing for rotating the worm shaft about its longitudinal axis. A second end of the worm shaft, opposite to the first end, is rotatably supported in a second bearing for rotating the worm shaft about its longitudinal axis. Specifically, the first and / or second bearings are designed as ball bearings. The second end of the worm shaft is assigned a driver. This driver can be designed as a motor, especially an electric motor. To rotate the worm shaft about its longitudinal axis, the driver is connected to the worm shaft in a force-transmitting manner.

[0007] Furthermore, the steering mechanism has a preload device, by means of which a predetermined force is applied to the worm shaft toward the worm wheel. Specifically, the preload device presses and / or pulls the worm shaft toward the worm wheel. The preload device has a first annular element, which in turn has at least one elastic spring element. This at least one elastic spring element generates or produces a predetermined force for pressing and / or pulling the worm shaft toward the worm wheel. Here, the at least one elastic spring element extends inward from the first annular element.

[0008] Advantageously, this allows for alternative, particularly simpler or less costly, design and / or assembly possibilities based on the at least one elastic spring element extending inward from the first annular element. Specifically, the at least one elastic spring element extends from the first annular element into the annular cavity of the first annular element. Here, the at least one elastic spring element may extend radially or at least with a radial component inward from the first annular element.

[0009] According to another embodiment, the preload device has a first elastic spring element and a second elastic spring element. Here, the two spring elements are oriented inwards from the first annular element and / or toward each other. In particular, the two spring elements are arranged opposite to each other and / or on two opposing sections of the first annular element. The two spring elements can extend inwards from the inside of the first annular element into the annular cavity of the first annular element. A first bearing is arranged between the two spring elements. Preferably, the first bearing is spring-loaded by its arrangement between the two spring elements. Here, based on the spring-loaded support of the first bearing and by means of a suitable design of the two spring elements, the worm shaft is pressed and / or pulled onto the worm wheel for interaction with it.

[0010] According to an improved embodiment, the two spring elements form a receiving portion for the first bearing. Alternatively, the two spring elements have a receiving portion for the first bearing, or the two spring elements are connected to the receiving portion for the first bearing, particularly in a material-fitting manner. The preload device and the two spring elements are designed such that, in the unassembled state, the position of the center point of the receiving portion differs from the position of the center point of the first annular element. In other words, the receiving portion and / or its center point in the unassembled state are eccentrically arranged relative to the center point of the first annular element. The center point of the receiving portion and the center point of the first annular element preferably coincide in the assembled state. In other words, the center point of the receiving portion and / or its center point in the assembled state are co-centered relative to the center point of the first annular element.

[0011] The steering mechanism may have a transmission housing. In particular, the preload device is disposed outside the transmission housing in the unassembled state. Preferably, the preload device is disposed inside the transmission housing in the assembled state. In the assembled state, the outer periphery of the first annular element can form-fit against the inner periphery and / or inner side of a section of the transmission housing. Preferably, the transmission housing has a hollow cylindrical section for accommodating the preload device. Thus, the preload device or the outer periphery of the first annular element can be supported on the inner side of the transmission housing and / or at the hollow cylindrical section.

[0012] Especially in the assembled state, the first end of the worm shaft is housed in the first bearing. Preferably, the position and / or center point of the housing are changed in the manner described above during the transition from the unassembled state to the assembled state, and during the arrangement of the preload device in the transmission housing and the establishment of the connection between the first bearing and the first end of the worm shaft. Then, based on this positional change, a predetermined force is obtained by means of the two spring elements to press and / or pull the worm shaft towards the worm wheel. In particular, the two spring elements are arranged symmetrically with respect to the center point of the first annular element and / or the housing in the assembled state.

[0013] Preferably, the center point of the receiving portion follows a linear or at least approximately linear motion trajectory when transitioning from an unassembled state to an assembled state. Specifically, this involves displacement of the receiving portion or its center point relative to the first annular element along a defined spatial axis, preferably a vertical axis. In particular, in the assembled state, the application of a predetermined force to the worm shaft, via two spring elements, is restricted in the direction following the linear motion trajectory and / or in the direction of the spatial axis. Preferably, the motion trajectory coincides with the central axis of the first annular element. Here, the central axis can also be the axis of symmetry of the first annular element. The central axis or axis of symmetry of the first annular element can, for example, be designed as a mirror axis. Preferably, the first annular element is designed as a ring and / or a hollow cylinder.

[0014] The receiving portion can rotate about its center point in the assembled state and relative to the unassembled state. Preferably, rotation of the first annular element is prevented and / or blocked. This allows rotation of the receiving portion relative to the first annular element. In particular, rotation of the receiving portion occurs when the receiving portion or pre-tightening device transitions from the unassembled state to the assembled state. In particular, the rotation of the receiving portion is limited to a single-digit angle range or to an angle less than 1°.

[0015] According to another embodiment, the maximum deflection of the at least one spring element and / or both spring elements during the transition from an unassembled state to an assembled state is limited by means of a stop. In particular, the stop is arranged and / or designed inside the first annular element. Here, the stop may be formed from a segment of the first annular element itself. Alternatively, the stop may be designed as a separate component connected to the inside of the first annular element in a suitable manner (e.g., material fit, form fit, and / or force fit). The stop is preferably assigned to the first spring element. Therefore, the stop can limit the deflection of the first spring element, particularly during the transition from an unassembled state to an assembled state, and thereby also limit the displacement of the receiving portion.

[0016] According to another embodiment, the preload device has a second annular element. In particular, the second annular element is designed as a ring and / or a hollow cylinder. The second annular element forms a receiving portion for the first bearing. For this purpose, the second annular element is arranged within the first annular element at a distance (especially a radial distance) from the first annular element, preferably within the annular cavity of the first annular element. Two spring elements correspondingly connect the first annular element and the second annular element. In particular, the second annular element is springily arranged or supported within the first annular element by means of these two spring elements. Preferably, the first bearing is arranged in the second annular element. In particular, the first bearing is arranged and / or fastened within the second annular element. Preferably, the first bearing is connected to the second annular element in such a way that relative movement between the second annular element and the first bearing is eliminated. This connection can be, for example, based on a press fit and / or material fit between the second annular element and the first bearing. Alternatively, and depending on the specific embodiment, the first bearing (especially when designed as a floating bearing) can be arranged and guided axially and displaceably relative to the second annular element within it.

[0017] The first annular element can be designed as an open annular element with a gap on its circumference. Specifically, in the unassembled state, the gap of the first annular element can be open. In the assembled state, the gap of the first annular element can be reduced or closed. The first annular element can be pressed into the transmission housing in the assembled state. Here, the outer circumference can be reduced and the gap at least partially or completely closed. In particular, the first annular element is arranged and / or connected to the transmission housing in an anti-rotational manner relative to the transmission housing. According to a specific embodiment, the first annular element can be arranged and / or fixed in the transmission housing, either axially displaceable or immovable.

[0018] According to another embodiment, the two spring elements respectively have spring tab sections capable of elastically bending about a bending axis arranged in a region of the first annular element. In particular, the bending axis is virtually designed and not a physical shaft. The spring tab sections and / or the end regions of the spring tab sections arranged away from the bending axis can be displaced about the bending axis and / or elastically bent in the assembled state and relative to the unassembled state. Preferably, the spring tab section of the first spring element elastically bends about the bending axis of the spring tab section of the first spring element toward the inside of the first annular element in the assembled state and relative to the unassembled state. This creates a spring action of the first spring element on the receiving portion and thus on the first end of the worm shaft in the assembled state. In particular, the first spring element presses the worm shaft against the worm wheel in the assembled state. The spring tab section of the second spring element elastically bends about the bending axis of the spring tab section of the second spring element away from the inside of the first annular element in the assembled state and relative to the unassembled state. Thus, in the assembled state, the spring force acts on the receiving part and / or the first bearing by means of the second spring element. In particular, in the assembled state, the worm shaft is pulled towards the worm wheel or onto the worm wheel by means of the second spring element.

[0019] According to an improved embodiment, the worm shaft is preloaded about the pivot axis toward the worm wheel by means of a preload device. Specifically, the pivot axis is implemented as a virtual axis and is therefore not a physical shaft. Preferably, the pivot axis is arranged in the region of the second bearing. The pivot axis may coincide with the center point of the second bearing. Based on the design and / or arrangement of the preload device and / or based on the two spring elements of the preload device, deflection of the worm shaft about the pivot axis in a direction perpendicular to the rotation axis of the worm wheel can be achieved. In particular, the pivot axis is oriented parallel to the rotation axis of the worm wheel. The deflectability of the worm shaft about the pivot axis can be obtained based on sufficient clearance in the second bearing. Simultaneously, movement or movement components of the worm shaft in a direction parallel to the rotation axis of the worm wheel are blocked. This blocking is particularly achieved based on the design of the preload device and / or the two spring elements.

[0020] These two spring elements can be material-fitted to the first annular element and the receiving portion. In particular, these two spring elements are material-fitted to the first annular element and the receiving portion designed as a second annular element. The spring elements can be formed from a section of the first annular element. Specifically, the spring elements are formed from a cut, stamped, and / or shaped tongue of material from the first annular element. This allows for the particularly cost-effective manufacture of a preload device with these two spring elements. Furthermore, since a material-fitted connection to the first annular element already exists, only additional material-fitted connections to the receiving portion or the second annular element need to be established. Alternatively, other, such as force-fitted and / or form-fitted, connections between the corresponding spring elements and the first annular element and the receiving portion or the second annular element are also conceivable.

[0021] According to another embodiment, the worm shaft is preloaded along its axial direction and in conjunction with the worm wheel by means of a resilient force-inducing element. For this purpose, the force-inducing element can be arranged in the region of the first bearing or the region of the second bearing. In particular, the force-inducing element is designed as part of the preload device. This allows for a particularly space-saving design. Axial preload of the worm shaft and engagement with the worm wheel are achieved by means of the force-inducing element. Therefore, undesirable clicking noise between the worm shaft and the worm wheel can be avoided, especially when the rotational direction of the worm shaft changes.

[0022] Force-inducing elements can be designed as springs, especially disc springs, helical springs, or wave springs.

[0023] A force-inducing element can be arranged between a stop element fixed in position to the transmission housing and a preload device that can be displaced axially relative to the worm shaft. Here, a first bearing is immovably connected to the preload device and the worm shaft in the axial direction of the worm shaft. In particular, the stop element is designed as an integral part of the transmission housing and / or immovably connected to the transmission housing.

[0024] Alternatively, the force-inducing element can be arranged between a stop element fixed in position to the preload device and a first bearing that can be displaced axially relative to the worm shaft. In particular, the stop element is designed as part of the preload device, especially the receiving portion and / or the second annular element. Here, the first bearing is immovably connected to the worm shaft in the axial direction and movably connected to the preload device in the axial direction of the worm shaft. Furthermore, the preload device is immovably connected to the transmission housing in the axial direction.

[0025] According to another embodiment, a force-inducing element is arranged between a stop element assigned to the worm shaft and a first bearing. In particular, the stop element is designed as a component of the worm shaft or a material step section. Here, the first bearing is preferably immovably connected to and / or immovably connected relative to the transmission housing by means of a preload device. Furthermore, the worm shaft is movably connected to the first bearing in the axial direction.

[0026] According to another alternative, the force-inducing element is arranged between the stop element assigned to the worm shaft and the second bearing. Specifically, the stop element is designed as a component of the worm shaft and / or a material stepped portion of the worm shaft. Here, the second bearing is immovably connected to the transmission housing. Furthermore, the worm shaft is movably connected to the second bearing in the axial direction.

[0027] This leads to different possibilities, namely, integrating the force-introducing element into the steering device or worm gear drive and achieving axial preload along the longitudinal direction of the worm shaft and between the worm shaft and the worm wheel.

[0028] According to an improved embodiment, at least one damping element is at least partially disposed between the first annular element and the second annular element. Specifically, the first and second damping elements are disposed between the first and second annular elements. Here, the two damping elements can be arranged opposite to each other and respectively disposed between the two spring elements. Preferably, the damping elements are connected to the inner circumference of the first annular element and the outer circumference of the second annular element, particularly by material mating. The damping elements can be formed of rubber, plastic, and / or foam materials. For example, the damping elements can be manufactured between the first and second annular elements by means of an injection molding process.

[0029] The invention will now be described in detail with the aid of the accompanying drawings. Here, the same reference numerals refer to the same, similar, or functionally identical components or elements. In the drawings:

[0030] Figure 1 A partial schematic cross-sectional side view of the first steering device according to the present invention is shown.

[0031] Figure 2 It shows the method for using according to Figure 1 A perspective side view of the first pretensioning device of the first steering device according to the present invention.

[0032] Figure 3a , Figure 3b They respectively showed according to Figure 2 Front views of the first pre-tightening device in its unassembled and assembled states.

[0033] Figure 4A front view of a second preload device with a damping element is shown.

[0034] Figure 5 A front view of the third pretensioning device is shown.

[0035] Figure 6a , Figure 6b The front views of the fourth pre-tightening device are shown in both the unassembled and assembled states.

[0036] Figure 7 A partial schematic cross-sectional side view of the second steering device according to the present invention is shown.

[0037] Figure 8 A partial schematic cross-sectional side view of the third steering device according to the present invention is shown.

[0038] Figure 9 A partial schematic cross-sectional side view of the fourth steering device according to the present invention is shown.

[0039] Figure 10 A partial schematic cross-sectional side view of another steering device according to the invention is shown, and

[0040] Figure 11a , Figure 11b , Figure 11c Partial front views of the respective pretensioning devices having stop portions are shown.

[0041] List of reference numerals

[0042] 1. First steering device

[0043] 2. Worm Gear Drive

[0044] 3 worm shafts

[0045] 4 worm gears

[0046] 5. Rotation axis

[0047] 6-axis longitudinal axis

[0048] 7 First end

[0049] 8 Second end

[0050] 9 First Bearing

[0051] 10 Second Bearing

[0052] 11 Transmission device housing

[0053] 12 drives

[0054] 13 inner side

[0055] 14 Force-introducing elements

[0056] 15 Pre-tightening device

[0057] 16 pivot axes

[0058] 17 Double Arrows

[0059] 18 First Ring Element

[0060] 19 Second annular element / receiving part

[0061] 20 First Spring Element

[0062] 21 Second Spring Element

[0063] 22 Material Shortage

[0064] 23 Material Shortage

[0065] 24 center points

[0066] 25 center points

[0067] 26 central axis

[0068] 27 Spring Connector Section

[0069] 28 Spring Connector Section

[0070] 29. Curved axis

[0071] 30 Bending Axis

[0072] 31 inner side

[0073] 32 arrows

[0074] 33 Pre-tightening device

[0075] 34 damping elements

[0076] 35 damping element

[0077] 36 gaps

[0078] 37 Pre-tightening device

[0079] 38 storage sections

[0080] 39 First Section

[0081] 40 Other sections

[0082] 41 Pre-tightening device

[0083] 42. Other central axes

[0084] 43 Second Steering Device

[0085] 44 Pre-tightening device

[0086] 45 material flange

[0087] 46 Material Cascade Section

[0088] 47 Stopping elements

[0089] 48 arrows

[0090] 49 Third Steering Device

[0091] 50 Pre-tightening device

[0092] 51 Stop element

[0093] 52 Fourth Steering Device

[0094] 53 Stop element

[0095] 54. Other steering mechanisms

[0096] 55 stop element

[0097] 56 Pre-tightening device

[0098] 57 Pre-tightening device

[0099] 58 Pre-tightening device

[0100] 59 Stop section

[0101] 60 Annular Cavity

[0102] Figure 1 A partial schematic cross-sectional side view of a first steering device 1 according to the present invention is shown. In this embodiment, the steering device 1 is designed as an electric servo steering device. Furthermore, the steering device 1 is configured for use in a vehicle or motor vehicle. The steering device 1 has a worm gear transmission 2. The worm gear transmission 2 has a worm shaft 3 and a worm wheel 4 that interacts with the worm shaft 3. Here, the worm wheel 4 is shown only schematically. The worm wheel 4 is rotatably supported about a rotation axis 5. The worm wheel 4 meshes with the worm shaft 3. Here, the longitudinal axis 6 of the worm shaft 3 is oriented laterally or perpendicularly to the rotation axis 5 of the worm wheel 4.

[0103] The worm shaft 3 has a first end 7 and a second end 8 opposite to the first end 7. The first end 7 of the worm shaft 3 is rotatably supported in a first bearing 9, and the second end 8 of the worm shaft 3 is rotatably supported in a second bearing 10. In this embodiment, the two bearings 9 and 10 are designed as ball bearings. The worm shaft 3 and the two bearings 9 and 10 are arranged within the transmission housing 11.

[0104] The second end 8 of the worm shaft 3 is connected to the drive 12 (shown only schematically here) in a force-transmitting manner to rotate the worm shaft 3 about its longitudinal axis 6. In this embodiment, the drive 12 is designed as an electric motor. In this embodiment, a second bearing 10 is arranged between the inner side 13 of the transmission housing 11 and the outer periphery of the second end 8 of the worm shaft 3.

[0105] Furthermore, in this embodiment, an elastic force-inducing element 14 is arranged in the region of the second end 8 of the worm shaft 3. The force-inducing element 14 is exemplarily implemented here as a helical spring. One end of the force-inducing element 14 is supported on the second end 8 of the worm shaft 3. The other end, opposite to this end, is supported on the actuator 12 or a drive shaft of the actuator 12 (not shown in detail here). The worm shaft 3 is preloaded along its axial direction according to arrow 48 and for interaction with the worm wheel 4 by means of the force-inducing element 14. This prevents unwanted interference noise or clicking sounds when the rotational direction of the worm shaft 3 changes.

[0106] The steering device 1 or worm gear transmission 2 has a preload device 15. The preload device 15 is arranged in the region of the first bearing 9. By means of the preload device 15, a predetermined force is applied to the worm shaft 3 in the direction of the worm wheel 4. For this purpose, the preload device 15 is arranged between the outer periphery of the first bearing 9 and the inner side 13 of the transmission housing 11. By means of the preload device 15, the worm shaft 3 is preloaded in the direction of the worm wheel 4 about a virtual pivot axis 16 arranged in the region of the second bearing 10.

[0107] In this embodiment, this deflectability is possible due to sufficient clearance in the second bearing 10. Furthermore, this deflectability of the worm shaft 3 is schematically illustrated by means of the double arrow 17 and two exemplary deflection axes 6.1 and 6.2 of the shaft.

[0108] The design and arrangement of the preload device 15 enable the worm shaft 3 to deflect about the pivot axis 16 in a direction perpendicular to the rotation axis 5 of the worm wheel 4, as schematically indicated by arrow 32. Simultaneously, it blocks or prevents the movement or motion component of the worm shaft 3 in a direction parallel to the rotation axis 5 of the worm wheel 4.

[0109] Therefore, according to the coordinate system shown here, the deflectability of the worm shaft 3 about the pivot axis 16 in the z-axis direction is limited. Additional preload on the worm shaft 3 in the direction of the worm wheel 4 and in the y-axis direction can be achieved by means of the force-inducing element 14. The x-axis, not shown in detail here, is arranged perpendicular to both the z-axis and the y-axis. The preload device 15 and the force-inducing element 14 are designed to prevent displacement of the worm shaft 3 in the x-axis direction. In other words, the movement of the worm shaft 3 for forming preload in its interaction with the worm wheel 4 is restricted to a plane extended by means of the z-axis and y-axis. The x-axis, y-axis, and z-axis can coincide with or be parallel to the corresponding vehicle longitudinal axis, vehicle lateral axis, and vehicle vertical axis. However, depending on the specific design and arrangement of the steering system, the x-axis, y-axis, and z-axis are alternatively oriented laterally to the corresponding vehicle longitudinal axis, vehicle lateral axis, and vehicle vertical axis.

[0110] According to the following Figure 2 and Figure 3a , Figure 3b The structure and working principle of the pre-tightening device 15 will be explained in more detail.

[0111] Figure 2 It shows the method for using according to Figure 1 A perspective side view of the first pretensioning device 15 of the first steering device 1 according to the present invention. The pretensioning device 15 has a first annular element 18 and a second annular element 19. In this embodiment, the two annular elements 18 and 19 are designed to be circular. The second annular element 19 is arranged within the first annular element 18 at a certain distance from the first annular element 18. Therefore, the diameter of the second annular element 19 is smaller than that of the first annular element 18.

[0112] Furthermore, the pretensioning device 15 has a resilient first spring element 20 and a resilient second spring element 21. These two spring elements 20 and 21 extend inward from the first annular element 18. In other words, these two spring elements 20 and 21 extend into the annular cavity 60 of the first annular element 18. Here, these two spring elements 20 and 21 correspondingly connect the first annular element 18 to the second annular element 19. The second annular element 19 is here formed for... Figure 1 The housing of the first bearing 9.

[0113] The two spring elements 20 and 21 are connected to the first annular element 18 and the second annular element 19 in a material-fitting manner. In this embodiment, the spring elements 20 and 21 are each formed from a segment of the first annular element 18. In this embodiment, the spring elements 20 and 21 are formed by means of material segments or material tongues cut or stamped from and subsequently shaped from the first annular element 18. Thus, the first annular element 18 has corresponding material notches 22 or 23 in the region of the spring element 20 or 21. The material notches 22 and 23 are designed here as gaps or slits extending in the circumferential direction of the first annular element 18.

[0114] Figure 3a and Figure 3b They respectively showed according to Figure 2 The first pre-tightening device 15 is shown in front views in its unassembled and assembled states. According to... Figure 3a In its unassembled state, the position of the center point 24 of the second annular element 19 differs from the position of the center point 25 of the first annular element 18. Conversely, according to... Figure 3b In the assembled state, the center point 24 of the second annular element 19 coincides with the center point 25 of the first annular element 18. In this embodiment, the two spring elements 20 and 21 are in accordance with... Figure 3b In the assembled state, the two annular elements 18 and 19 are arranged or designed symmetrically with respect to the center point 24 of the second annular element 19 and the center point 25 of the first annular element 18 that coincides with the center point of the first annular element 18. Furthermore, the two annular elements 18 and 19 are arranged concentrically with each other in the assembled state.

[0115] During the transition from an unassembled state to an assembled state, the center point 24 of the second annular element 19 follows a linear motion trajectory. In this embodiment, this linear motion trajectory coincides with the central axis 26 of the first annular element 18. In this embodiment, the central axis 26 is parallel to the axis of the first annular element 18. Figure 1 The z-axis extension.

[0116] Furthermore, during the transition from the unassembled state to the assembled state, the second annular element 19 can rotate around its center point 24. Whether the second annular element rotates around the center point 24 and the extent of its rotation depends on the specific design and arrangement of the spring elements 20 and 21. This rotation is typically a few degrees, for example, less than 10° or less than 5°. In the embodiment shown here, the second annular element 19 hardly rotates during the transition from the unassembled state to the assembled state.

[0117] According to the pre-tightening device 15 Figure 3b The assembled state and according to Figure 1The installation situation corresponds accordingly. Thus, in the assembled state, a first bearing 9 (not shown in detail here) is arranged in the second annular element 19, wherein the first end 7 of the worm shaft 3 (also not shown in detail here) is supported in the first bearing 9.

[0118] The two spring elements 20 and 21 respectively have spring tab sections 27 or 28. The spring tab sections 27 or 28 are respectively elastically bendable about a virtual bending axis 29 or 30 arranged in the region of the first annular element 18. The spring tab section 27 of the first spring element 20, in the assembled state and relative to the unassembled state, is elastically bent about the bending axis 29 of the spring tab section 27 of the first spring element 27 toward the inner side 31 of the first annular element 18. Furthermore, the spring tab section 28 of the second spring element 21, in the assembled state and relative to the unassembled state, is elastically bent away from the inner side 31 of the first annular element 18 about the bending axis 30 of the spring tab section 28 of the second spring element 21. Thus, in the assembled state, the desired preload is obtained in the direction of the worm shaft 3 toward the worm wheel 4, as this... Figure 1 and Figure 3b As indicated by arrow 32. Here, according to this example, preload is obtained in the z-axis direction.

[0119] According to Figures 1 to 3b In the preload device 15, the spring element 20 presses the first end 7, and thereby the entire worm shaft 3, onto the worm wheel 4. At the same time, the spring element 21 pulls the first end 7 or the entire worm shaft 3 onto the worm wheel 4.

[0120] Figure 4 A front view of a second preload device 33 with damping elements 34 and 35 is shown. Here, the preload device 33 is shown in its assembled state, with the transmission housing 11 omitted from the view. The structure and operating principle of the preload device 33 largely correspond to... Figures 1 to 3b The pre-tightening device 15. The same features have the same reference numerals as before. In this regard, reference is also made to the above description to avoid repetition.

[0121] Unlike the pre-tightening device 15, in the pre-tightening device 33 shown here, the first annular element 18 is designed as an open annular element with a gap 36 on its circumference. During the transition from an unassembled state to an assembled state, the gap 36 of the first annular element 18 can be completely or partially closed, as in this example.

[0122] Furthermore, in this embodiment, a first damping element 34 and a second damping element 35 are arranged between the first annular element 18 and the second annular element 19. Here, the two damping elements 34 and 35 are arranged opposite to each other and are respectively arranged between the two spring elements 20 and 21. In addition, in this embodiment, the second damping element 35 covers the gap 36. The damping elements 34 and 35 can be formed of plastic, rubber, or foam material.

[0123] Figure 5 A front view of the third pre-tightening device 37 is shown. The same features have the same reference numerals as before. For this purpose, reference is also made to the above description to avoid repetition.

[0124] The preload device 37 is shown here in its assembled state, while the transmission housing 11 is not shown in detail here.

[0125] In this embodiment, the second annular element 19 is omitted. Instead, the free ends of the two spring elements 20, 21 form a receiving portion 38 for the first bearing 9. To form the receiving portion 38, according to this embodiment, at least one first segment 39 of the free end of the first spring element 20 or the second spring element 21 points in a first circumferential direction of the first bearing 9. Furthermore, to form the receiving portion 38, according to this embodiment, at least one additional segment 40 of the free end of the first spring element 20 or the second spring element 21 points in a second circumferential direction of the first bearing 9 opposite to the first circumferential direction. Thus, the free ends of the first spring element 20 or the second spring element 21 can have a V-shaped or C-shaped shape. The first bearing 9 is received between the free ends of the two spring elements 20, 21. Here, segments 39, 40 are themselves designed to be inelastic and / or sufficiently rigid to avoid undesirable movement of the first bearing 9 transverse to the central axis 26.

[0126] However, the basic working principle and basis of the pre-tightening device 37 Figure 3a and Figure 3b The pre-tightening device 15 corresponds to this. Refer also to the description there. Therefore, according to... Figure 5 In the preload device 37, the spring element 20 is pressed against the first end 7 in the assembled state or presses the entire worm shaft 3 against the worm wheel 4. However, in the opposite case, in the preload device 37, the spring element 21 only functions as a mating retainer, but it has no tension or pressure that can be applied to the worm shaft 3 or its first end 7.

[0127] Figure 6a and Figure 6b The front views of the fourth preload device 41 are shown in both the unassembled and assembled states. The preload device 41 is related to... Figure 5The pre-tightening device 37 is similarly designed. The same features have the same reference numerals as before. Refer also to the above description for this purpose.

[0128] Unlike the preload device 37, the spring elements 20 and 21, in the preload device 41 shown here, are not arranged or oriented along the central axis 26 with their free ends, but rather in the region of a separate central axis 42 oriented at right angles to the central axis 26. The separate central axis 42 of the first annular element 18, in this embodiment, is oriented parallel to the x-axis or the axis of rotation 5 of the worm gear 4, which is not shown in detail here.

[0129] According to Figure 6a and Figure 6b In the pre-tightening device 41, the two spring elements 20 and 21 apply pressure to the first end 7 or the entire worm shaft 3 in the assembled state, thereby pressing the worm shaft 3 onto the worm wheel 4.

[0130] Figure 7 A partial schematic cross-sectional side view of the second steering device 43 according to the invention is shown. The same features have the same reference numerals as before. Reference is also made to the above description for this purpose. For clarity, the worm gear 4 is omitted here.

[0131] The second steering device 43 has a pretensioning device 44. The pretensioning device 44 is similar in structure and working principle to that of the steering mechanism 43. Figures 1 to 3b Corresponding to the preload device 15. Refer also to the above description for this purpose. Additionally, the preload device 44 has a material flange 45 disposed away from the second bearing 10. Here, the first bearing 9 is disposed between the material flange 45 of the preload device 44 and the material step portion 46 of the worm shaft 3.

[0132] The steering mechanism 43 has a force-introducing element 14, which is designed as a disc spring in this embodiment. Furthermore, the force-introducing element 14 is arranged in the region of the first bearing 9 in the steering mechanism 43 shown here. Specifically, the force-introducing element 14 is arranged between a fixed stop element 47 and a preload device 44 that is axially displaceable relative to the worm shaft 3. The stop element 47 is designed as annular in this embodiment. Furthermore, the stop element 47 is assigned to the transmission housing 11. Here, the stop element 47 is fixedly connected to the inner side 13 of the transmission housing 11. Thus, the worm shaft 3 is preloaded by means of the force-introducing element 14 in the axial direction of the worm shaft 3 according to arrow 48 and in order to cooperate with the worm wheel 4.

[0133] Figure 8A partial schematic cross-sectional side view of the third steering device 49 according to the invention is shown. For clarity, the worm gear 4 and the transmission housing 11 are omitted. The same features have the same reference numerals as before. Reference also goes to the above description for this purpose.

[0134] The steering device 49 has a pretensioning device 50. The pretensioning device 50 is based on... Figure 7 The preload device 44 is similarly designed. However, the preload device 50 has a stop element 51 instead of a material flange 45. The stop element 51 closes the second annular element 19 in the region away from the second bearing 10. Thus, the stop element 51 forms the sidewall of the preload device 50 away from the second bearing 10.

[0135] Furthermore, in this embodiment, the force-inducing element 14 (designed here as a disc spring) is arranged between the fixed-position stop element 51 and the first bearing 9, which is movable relative to the worm shaft 3 in the axial direction. Here, the first bearing 9 is immovably connected to the worm shaft 3 in the axial direction and simultaneously movablely connected to the preload device 50 in the axial direction of the worm shaft 3. The preload device 50 is then immovably connected to the transmission housing 11 (not shown in detail here) in the axial direction of the worm shaft 3. Thus, the preload device 50 is designed to form a preload on the worm shaft 3 in the z-axis direction and a preload in the y-axis direction in conjunction with the worm wheel 4.

[0136] Figure 9 A partial schematic cross-sectional side view of the fourth steering device 52 according to the invention is shown. The same features have the same reference numerals as before. Reference is also made to the above description in this regard. For clarity, the transmission housing 11 and the worm gear 4 are omitted from the illustration.

[0137] Steering device 52 as in accordance with Figure 7 The second steering device 43 has a preload device 44, as in the description therein.

[0138] Unlike the steering mechanism 43, in the steering mechanism 52 shown here, the force-introducing element 14 (designed here as a disc spring) is arranged in the region of the second bearing 10. Specifically, the force-introducing element 14 is arranged between the stop element 53 assigned to the worm shaft 3 and the second bearing 10. In this embodiment, the stop element 53 is designed as a material stepped portion of the worm shaft 3. The second bearing 10 is fixedly or immovably connected to the transmission housing 11, which is not shown in detail here. Furthermore, the worm shaft 3 is movably or displaceably connected to the second bearing 10 in the axial direction of the worm shaft 3. Thus, on the one hand, preload acting on the worm shaft 3 in the y-axis direction can be introduced by means of the preload device 44, and on the other hand, preload acting in the y-axis direction can be introduced by means of the force-introducing element 14, in the y-axis direction, for preloading the worm shaft 3 in conjunction with the worm wheel 4.

[0139] Figure 10 A partial schematic cross-sectional side view of another steering device 54 according to the invention is shown. The same features have the same reference numerals as before. Reference is also made to the above description for this purpose. For clarity, the transmission housing 11 and the worm gear 4 are omitted from the illustration.

[0140] Steering device 54 is also as follows: Figure 7 The second steering device 43 has a preload device 44, as described above. Refer to the steering device 54 shown here as well. However, according to the steering device 54 shown here, the force-introducing element 14 (designed here as a helical spring) is arranged between the stop element 55 assigned to the worm shaft 3 and the first bearing 9. In this embodiment, the stop element 55 is designed as a material step portion in the worm shaft 3. The first bearing 9 is then immovably connected to or immovably connected relative to the transmission housing 11 (not shown in detail here) by means of the preload device 44. Furthermore, the worm shaft 3 is movably or linearly displaceable connected to the first bearing 9 in its axial direction. Thus, the steering device 54 can also achieve preload of the worm shaft 3 in the z-axis and y-axis directions in its interaction with the worm wheel 4.

[0141] Figure 11a , Figure 11b and Figure 11c Partial front views of the additional pretensioning devices 56, 57, and 58, each having a stop 59, are shown respectively. The pretensioning devices 56, 57, and 58 are substantially the same in structure and operating principle as those according to... Figures 1 to 3b The pretensioning device 15 corresponds to this. However, pretensioning devices 33, 37, 41, 44, or 50 may also have corresponding pretensioning devices according to... Figure 11a , Figure 11b or Figure 11cStop part 59.

[0142] The preload devices 56, 57, and 58 each have a stop 59. The stop 59 is used to limit the maximum deflection of the two spring elements 20 and 21 when transitioning from an unassembled state to an assembled state.

[0143] according to Figure 11a The stop portion 59 is arranged inside the first annular element 18 31 and adjacent to the first spring element 20. Here, according to Figure 11a In one embodiment, the stop 59 is designed as a separate component, for example, fixed to the inner side 31 by material fit.

[0144] However, in comparison, according to Figure 11b and Figure 11c In one embodiment, the stop portion 59 is correspondingly formed from a segment of the first annular element 18 itself (e.g., by means of cutting, stamping and / or forming).

[0145] according to Figure 11b The stop portion 59 is formed by a section of the first annular element 18 that is separate from the first spring element 20, wherein this section is shaped inward from the first annular element 18 toward the second annular element 19. Thus, in this embodiment, the second annular element 19 collides with the stop portion 59 of the first annular element 18 at maximum deflection.

[0146] according to Figure 11c The stop portion 59 is designed as the free end of the spring element 20. Here, the free end of the stop portion 59 faces the inner side 31 of the first annular element 18. Thus, at maximum deflection, the free end of the stop portion 59 stops at the inner side 31 of the first annular element 18. The free end of the spring element 20 forming the stop portion 59 is designed to be wider than the section of the spring element 20 that is different from the stop portion 59. The spring element 20 is connected to the second annular element 19, wherein the stop portion 59 extends away from the second annular element 19 toward the first annular element 18. The spring element 20 and the stop portion 59 are formed by the only common section of the first annular element 18. Due to the larger width of the stop portion 59 and its suitable shaping or orientation, it prevents the stop portion 59 from being impacted by gaps in the first annular element 18 formed by the manufacturing of the spring element 20 or the stop portion 59.

[0147] Stop 59 according to Figure 11a , Figure 11b or Figure 11c The implementation scheme may include additional damping portions or damping layers as needed. This prevents or minimizes noise that might otherwise interfere when the stop portion 59 stops or contacts to limit the maximum deflection of the two spring elements 20, 21.

Claims

1. A steering device having a worm gear drive (2), the worm gear drive having a worm shaft (3) and a worm wheel (4) acting in conjunction with the worm shaft (3), wherein a first end (7) of the worm shaft (3) is rotatably supported in a first bearing (9), and a second end (8) of the worm shaft (3) opposite to the first end (7) is rotatably supported in a second bearing (10), and the second end (8) of the worm shaft (3) is assigned a drive (12) connected to the worm shaft in a force-transmitting manner to rotate the worm shaft (3) about its longitudinal axis (6); and the steering device having a preload device (15, 33, 37). , 41, 44, 50, 56, 57, 58), wherein by means of the preload device (15, 33, 37, 41, 44, 50, 56, 57, 58), the worm shaft (3) is subjected to a predetermined force toward the worm wheel (4), and the preload device (15, 33, 37, 41, 44, 50, 56, 57, 58) has a first annular element (18), the first annular element having at least one elastic spring element (20, 21), wherein by means of the at least one elastic spring element (20, 21) a predetermined force is generated for pressing and / or pulling the worm shaft (3) onto the worm wheel (4), characterized in that, The at least one resilient spring element (20, 21) extends inwardly from the first annular element (18), the preload device (15, 33, 37, 41, 44, 50, 56, 57, 58) has a resilient first spring element and a resilient second spring element, wherein the two spring elements (20, 21) are arranged inwardly from the first annular element (18) and / or oriented toward each other, and the first bearing (9) is arranged between the two spring elements (20, 21), each of the two spring elements (20, 21) having a spring tab section (27, 28) that resiliently wraps around a cloth. The bending axis (29, 30) located in the region of the first annular element is bendable, and the spring contact section (27) of the first spring element is elastically bent toward the inner side (31) of the first annular element (18) about the bending axis (29) of the spring contact section (27) of the first spring element in the assembled state and relative to the unassembled state, wherein the spring contact section (28) of the second spring element is elastically bent away from the inner side (31) of the first annular element (18) about the bending axis (30) of the spring contact section (28) of the second spring element in the assembled state and relative to the unassembled state.

2. The steering device according to claim 1, characterized by The bending axis (29, 30) is virtual.

3. The steering device of claim 1, wherein The two spring elements (20, 21) form or have a receiving portion (19, 38) for the first bearing (9) or are connected to a receiving portion (19, 38) for the first bearing (9), wherein the position of the center point (24) of the receiving portion (19, 38) in the unassembled state is different from the position of the center point (25) of the first annular element (18).

4. The steering device according to claim 3, characterized in that, In the assembled state, the center point (24) of the receiving part (19, 38) coincides with the center point (25) of the first annular element (18).

5. The steering device of claim 4, wherein The two spring elements (20, 21) are arranged symmetrically with respect to the center points (24, 25) of the first annular element (18) and the receiving portion (19, 38) in the assembled state.

6. The steering device of claim 3, wherein The center point (24) of the receiving part (19, 38) follows a linear motion trajectory when transitioning from the unassembled state to the assembled state.

7. The steering device of claim 6, wherein The linear motion trajectory coincides with the central axis (26) of the first annular element (18).

8. The steering device of claim 7, wherein The receiving portion (19, 38) rotates about its center point (24) in the assembled state relative to the unassembled state.

9. The steering device according to any one of claims 3 to 8, characterized by The maximum deflection of at least one spring element during the transition from the unassembled state to the assembled state is limited by means of a stop (59).

10. The steering device according to claim 9, characterized in that, The stop (59) is arranged and / or designed on the inside (31) of the first annular element (18).

11. The steering device of claim 10, wherein The stop portion (59) is formed by a section of the first annular element (18).

12. The steering device according to any one of claims 3 to 8, characterized by The preload device (15, 33, 44, 50, 56, 57, 58) has a second annular element that forms a receiving portion for the first bearing (9), wherein the second annular element is arranged within the first annular element (18) at a certain distance from the first annular element (18), and the two spring elements (20, 21) respectively connect the first annular element (18) and the second annular element.

13. The steering device according to claim 12, characterized in that, The first bearing (9) is arranged in the second annular element.

14. The steering device of claim 13, wherein The first annular element (18) is designed as an open annular element with a gap (36) on its circumference.

15. The steering device according to any one of claims 1 to 8, characterized by The worm shaft (3) is preloaded about the pivot axis (16) toward the worm wheel (4) by means of the preload devices (15, 33, 37, 41, 44, 50, 56, 57, 58), wherein the design and / or arrangement of the preload devices (15, 33, 37, 41, 44, 50, 56, 57, 58) and / or the two spring elements (20, 21) enable the worm shaft (3) to deflect about the pivot axis (16) in a direction perpendicular to the rotation axis (5) of the worm wheel (4), and simultaneously block the movement and / or movement component of the worm shaft (3) in a direction parallel to the rotation axis (5) of the worm wheel (4).

16. The steering device of claim 15, wherein The pivot axis (16) is virtual and / or arranged in the region of the second bearing (10).

17. The steering device according to any one of claims 1 to 8, characterized by The two spring elements (20, 21) are connected to the first annular element (18) and the receiving portion (19, 38) in a material-fitting manner.

18. The steering device according to any one of claims 1 to 8, characterized by The two spring elements (20, 21) are connected to the receiving portion, which is designed as a second annular element, in a material-fitting manner.

19. The steering device of claim 17, wherein The spring elements (20, 21) are formed from the cut, stamped and / or shaped material tongue of the first annular element (18).

20. The steering device according to any one of claims 1 to 8, characterized in that, The worm shaft (3) is preloaded along the axial direction of the worm shaft (3) and in conjunction with the worm wheel (4) by means of an elastic force-inducing element (14), wherein the force-inducing element (14) is arranged in the region of the first bearing (9) or in the region of the second bearing (10).

21. The steering device of claim 20, wherein, The force-introducing element (14) is designed as a component of the pre-tightening device (15, 33, 37, 41, 44, 50, 56, 57, 58).

22. The steering apparatus of claim 20, wherein The force-introducing element (14) - A stop element (47) fixed in position in the housing (11) of the dispensing transmission device is positioned between a preload device (44) which is displaceable relative to the worm shaft (3) in the axial direction, wherein the first bearing (9) is nonmovably connected to the preload device (44) and the worm shaft (3) in the axial direction of the worm shaft (3). or - A stop element (51) fixed in position assigned to the preload device (50) is positioned between a first bearing (9) which is movably arranged relative to the worm shaft (3) in the axial direction, wherein the first bearing (9) is immovably connected to the worm shaft (3) in the axial direction and movably connected to the preload device (50) in the axial direction, and the preload device (50) is immovably connected to the transmission housing (11) in the axial direction; or -A stop element (55) assigned to the worm shaft (3) is arranged between the first bearing (9), wherein the first bearing (9) is immovably connected to the transmission housing (11) and / or immovably connected relative to the transmission housing, and the worm shaft (3) is movably connected to the first bearing (9) in the axial direction. or -A stop element (53) assigned to the worm shaft (3) is arranged between the stop element (53) and the second bearing (10), wherein the second bearing (10) is immovably connected to the transmission housing (11), and the worm shaft (3) is movably connected to the second bearing (10) in the axial direction.

23. The steering device according to claim 22, characterized in that, The force-introducing element (14) is designed as a spring.

24. The steering device according to claim 22, characterized in that, The first bearing (9) is immovably connected to the transmission housing (11) by means of the preload device (44) and / or immovably connected relative to the transmission housing.

25. The steering device according to claim 12, characterized in that, At least one damping element (34, 35) is arranged at least partially between the first annular element (18) and the second annular element.

26. The steering apparatus of claim 25, wherein The first and second damping elements of the at least one damping element (34, 35) are arranged between the first annular element (18) and the second annular element.

27. The steering apparatus of claim 26, wherein The first damping element and the second damping element are arranged opposite to each other and are respectively arranged between the two spring elements (20, 21).

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