WO2019134814A1 - Steering gear for a motor vehicle - Google Patents

Abstract

The invention relates to a steering gear for a steering system of a motor vehicle, which system comprises at least one housing (1), a gearwheel (2), a pinion (3) which meshes with the gearwheel (2), and a pinion shaft (4) that encompasses the pinion (3), the pinion shaft (4) being mounted, at one end of the pinion (3), in a fixed bearing (6) that comprises a rotary bearing (9) in which the pinion shaft (4) is held, and which is held in a fixed-bearing sleeve (14), and the fixed bearing (6) also comprising a pivot ring (15), which has an outer ring (19) and an inner ring (16) which are interconnected by one or more torsion links so as to be pivotable about a pivot axis defined by the torsion link or links, the inner ring (16) being held in the fixed-bearing sleeve (14) and the outer ring (19) being mounted inside the housing (1). The steering gear is characterised in that the outer ring (19) of the pivot ring (15) is mounted inside the housing (1) so as to be rotatable about a rotational axis (28) that is positioned transversely, and in particular perpendicularly, to the pivot axis.

Description

 Steering gear for a motor vehicle

The invention relates to a steering gear for a steering system of a motor vehicle and a steering system with such a steering gear. The steering system may in particular be a power steering system.

In most motor vehicles, power steering systems are installed, which generate a supportive torque during steering and thereby reduce the steering torque to be applied by the driver to the steering column.

The known power steering systems are based on a steering gear that the

Translated drive power of a hydraulic or electric steering motor and transmits, for example, the steering column. Such steering gears are regularly in the form of a Schraubwälzgetriebes and in particular as Schraubradgetriebe or as a worm gear. These include a gear which is directly or indirectly connected to the steering column, as well as a meshing therewith, via a shaft driven by the steering motor pinion.

As a problem with such steering gears, gear play has shown that due to component tolerances, different thermal expansion of the

Gear elements, formed due to wear and / or due to a setting of the material in gears made of plastic. Especially with a

so-called change axes, i. in a direct successive steering with changing steering direction, such a gear play generates unwanted noise, resulting from the alternate application of opposite flanks of the teeth of the pinion and gear.

It is known to eliminate this gear play in that the pinion shaft is pivotally mounted about an axis which is perpendicular to the longitudinal axis of the pinion shaft and at a distance from the meshing engagement of pinion and gear, and is pressed by means of one or more spring elements against the gear , The pivoting of the pinion shaft is doing regularly in one of the two

Bearings over which the pinion shaft is mounted end-integrated. This storage is referred to as a fixed bearing. The storage in the region of the other end is then carried out with a defined mobility (so-called floating bearing) in order to allow the deflection associated with such a pivoting movement. The

Fixed bearing may in particular be provided on the drive side, while the floating bearing is provided at the free end of the pinion shaft. The one or more spring elements for Pressing the pinion to the gear can be integrated both in the movable bearing and in the fixed bearing.

Such a steering gear, in which the spring force is generated for springing by means of the fixed bearing, is known for example from DE 10 2008 040 673 A1 and EP 2 836 417 B1. A steering gear, in which the spring force for the springing, however, is generated in the area of the floating bearing is, for example, from

DE 10 2008 001 878 A1.

The pivotability of the pinion shaft defined by the fixed bearing

Pivot axis must be given in a defined minimum, the so-called basic game, to avoid the pinion shaft due to temperature-induced strains, due to changes in geometry made of plastic elements of the steering gear, in particular the gear and / or the pinion shaft, due to water absorption and as a result of To allow runout of the gear and / or the pinion shaft. At the same time, the basic game must be limited, since then when using the pinion shaft, a drive power is transmitted from a steering motor to the gear, the spring-loaded pinion shaft is pivoted due to the toothing forces in the direction of increasing distance from the gear until an end stop for this pivotal movement, the can be formed in particular from the floating bearing of the steering gear is reached.

That in the context of the structural design of such a steering gear

dimensioned basic play increases in the course of use due to wear as well as due to settling, i. due to a plastic deformation due to a permanent load, the elements of the steering gear, in particular in their design made of plastics). Even production-related shape and position tolerances can lead to an increase in the basic game. This results in that when dimensioning the springing for the pinion shaft, which also takes into account a presumably given at the end of a scheduled service life of the steering gear basic game, even then should be given a sufficiently strong springing, the spring load in the new condition of the steering gear chosen so large must be that an undesirably high friction occurs in the toothing.

Therefore, it would be advantageous to have a basic play that is as constant as possible over the intended service life, which in addition is only dimensioned so large that the expected influences on the gear play, in particular as a result of Temperature-induced strains, water absorption and / or manufacturing tolerances can be compensated without leading to an undesirably high friction in the toothing.

In the hitherto unpublished German patent application 10 2017 209 563.6 a steering gear is claimed in which this goal is achieved in that the pivot bearing of the floating bearing is received in a floating bearing sleeve, wherein the

Floating sleeve with a guide element and the guide element with a holding element, which is for fixed integration within a housing of the

Steering gear is provided, such interaction that the floating bearing sleeve in a first direction, which is radial with respect to the longitudinal axis of the floating bearing sleeve and also perpendicular to that of the fixed bearing (according to those from DE 10 2008 040 673 A1 and EP 2,836,417 B1 are formed) trained pivot axis is aligned relative to the holding element is movable when the Schraubritzelwelle is not loaded with a torque, while such relative movement is prevented when the Schraubritzelwelle with a

Torque is loaded by then the floating bearing sleeve in a second direction, which is also radially aligned with respect to the longitudinal axis of the floating bearing sleeve and also perpendicular to the first direction is moved relative to the holding element, whereby the guide element in a guide opening of the holding element or the

Floating sleeve tilted.

The operating principle of the floating bearing of the German patent application

10 2017 209 563.6 stressed steering gear is based on the fact that due to the design of the pinion as a sprocket in the transmission of a drive power, which is transmitted from a steering motor to the Schraubritzelwelle and the Schraubritzelwelle on the gear, the Schraubritzelwelle not only to the actual due to the Verzahnungskräfte Pivot axis of the fixed bearing but is pivoted to a small extent about a perpendicular to this pivot axis located second axis, which is due to clearance or elastic deformability in the storage of Schraubritzelwelle, especially in the fixed bearing. This is exploited by means of the special design of the movable bearing to a defined, albeit relatively small deflection (pivoting) of the

Schraubritzelwelle about this second axis to cause the tilting of the guide member in the guide hole, which then also pivoting the

Screw pinion shaft is limited or prevented by the actual pivot axis. Accordingly, by the interaction of the guide element and the guide opening a clamping acting stop for the

Pivoting movement of the screw pinion shaft created around the (actual) pivot axis, which, regardless of the actual state of wear of the

Steering gear and in particular of the gear and the Schraubritzels, this have this / these depending on the service life, always according to

Substantially same pivotal movement about the axis perpendicular to the actual pivot axis located second axis is effective, the size of this

Pivoting movement about the second axis over the useful life of the steering gear is substantially constant. Practically, due to the springing of the

Schraubritzelwelle be achieved that the clamping stop acting becomes effective before the forces generated by the load of the Schraubritzelwelle counteract the springing overcompensate the springing, so that such a floating bearing pivoting the Schraubritzelwelle to the defined by the fixed bearing pivot axis and as a result the load of the screw pinion shaft with a

Torque substantially immediate and thus completely prevented.

So that this functionality of the known from the German patent application 10 2017 209 563.6 floating bearing can be used as advantageous as possible, should

Deflection of the screw pinion shaft about the said second axis can be done as low resistance as possible. It has been shown that this is described by the combination with that described in the German patent application 10 2017 209 563.6

Fixed storage is not optimally implemented.

The invention therefore an object of the invention to provide an improved fixed bearing for a steering gear of a motor vehicle that in particular advantageously with a floating bearing, as in the German patent application

10 2017 209 563.6 is disclosed, can be combined.

This object is achieved by means of a steering gear for a motor vehicle according to claim 1. Advantageous embodiments of the steering gear according to the invention are subject matter of the dependent claims and / or emerge from the following description of the invention.

An inventive steering gear for a steering system of a motor vehicle comprises at least one housing, a gear, a pinion meshing with the gear, in particular screw pinion, and a pinion shaft comprising the pinion. The

Pinion shaft is mounted on one side of the pinion in a fixed bearing, the one Swivel bearing (preferably a rolling bearing, particularly preferably a ball bearing) comprises, in which the pinion shaft is received. The pivot itself is in one

Fixed bearing sleeve added. The fixed bearing further comprises a pivot ring which has an outer ring and an inner ring, which are connected to one another via one or more torsion bars pivotally about a defined by the torsion bars or the pivot axis, wherein the inner ring is received in the bearing sleeve and the outer ring within the housing, in particular directly or indirectly in or on the housing is stored. It is provided that the outer ring of the pivot ring is rotatably mounted about a transversely and in particular perpendicular to the pivot axis axis of rotation within the housing.

The additional rotation or pivoting (ie rotatability by less than 360 °) of the pinion shaft about the transverse axis and in particular perpendicular to the pivot axis axis of rotation, which is realized by the inventive design of the fixed bearing, in particular has advantages in an embodiment of the steering gear, in the according to the German patent application

10 2017 209 563.6 the pinion shaft is mounted on the other side of the pinion in a floating bearing, which comprises a pivot bearing (preferably a rolling bearing, particularly preferably a ball bearing) having an inner bearing ring in which the Schraubritzelwelle is received, and an outer Bearing ring in one

Non-bearing sleeve integrated (i.e., incorporated therein or formed by the floating bearing sleeve itself), wherein the floating bearing sleeve with a (preferably

bolt-shaped) guide element and the guide element with a holding element which is provided for fixed integration within the housing of the steering gear, such interaction that the floating bearing sleeve in a first direction, which is radial with respect to the longitudinal axis of the floating bearing sleeve and also perpendicular to the pivot axis formed by the fixed bearing is aligned relative to the holding element is movable when the Schraubritzelwelle unloaded, ie not loaded with a torque. Such a relative movement is prevented, however, when the Schraubritzelwelle is loaded with a torque, because then the floating bearing sleeve in a second direction, which is also radially with respect to the

Longitudinal axis of the floating bearing sleeve and is also aligned perpendicular to the first direction is moved relative to the holding element, whereby the

Guide element in a guide opening of the holding element or the floating bearing sleeve (or connected to the floating bearing sleeve element) tilted. The required for such tilting, albeit low mobility of the pinion shaft in the region of the movable bearing in the second direction, which corresponds to a pivoting of the pinion shaft about the axis formed by the fixed axis of rotation is possible due to the inventive design of the fixed bearing possible low resistance, since this only the bearing friction, in which this axis of rotation

defining pivot bearing in such a pan occurs, must be overcome.

The fixed integration of the retaining element in the housing of the steering gear can preferably be effected in that the holding element of the housing itself formed or directly connected to the housing (for example screwed or otherwise non-positively and / or positively and / or

cohesively connected) is.

However, an inventive steering gear can be advantageously combined with differently designed movable bearings.

According to the invention, the term "longitudinal axis" is understood to mean that axis of a body or of a cavity which extends along the greatest longitudinal extent of the body

Body / cavity runs and thereby the geometric centers of

different cross sections of the body / cavity connects.

According to a structurally advantageous embodiment of a steering gear according to the invention can be provided that the outer ring of the pivot ring itself forms two preferably cylindrical bearing pin or two preferably cylindrical bearing mounts whose coaxially aligned longitudinal axes correspond to the axis of rotation. Alternatively, it may also be advantageous that the outer ring of the pivot ring is preferably secured against rotation and

in particular immovable is received in a bearing bush of the floating bearing. This bearing bush can then form two preferably cylindrical bearing journals or two preferably cylindrical bearing mounts whose coaxially aligned longitudinal axes correspond to the axis of rotation. The bearing journals can furthermore preferably be rotatably received in each case within a preferably cylindrical bearing receptacle of the housing itself or one bearing journal of the housing is rotatably received in the bearing receptacles of the outer ring or the bearing bushing, whereby a structurally simple and in particular compact design for a steering gear according to the invention can be realized can. Alternatively, however, an indirect (rotatable) mounting of the bearing device with respect to the axis of rotation can be provided within the housing by

For example, the bearing journals are each rotatably received in a bearing receptacle of another component, which in turn is preferably immovably mounted within the housing.

To realize a structurally advantageous embodiment of a

Steering gear according to the invention can be provided that the outer ring of the pivot ring and / or the bearing bush a tubular portion

have / have, from which extend the journals. The journals may be particularly preferably received as separate components in each case in an opening or recess of the tubular portion, which may result in an advantageous manufacturability for such an inventive steering gear. The journals can be glued, welded or soldered in particular within the opening or depression of the tubular portion.

An embodiment of a steering gear according to the invention, in which the outer ring of the pivot ring is received within a bearing bush, a

Anti-rotation, which ensures against rotation of the bearing bush relative to the outer ring of the swivel ring, be realized in an advantageous manner by the fact that the outer ring of the swivel ring forms at least one projection which engages in a recess of the bearing bush. The one or more projections of the outer ring of the swivel ring can further preferably engage in recesses of the bearing bush, which are formed (respectively) within one of the bearing journals. As a result, a relatively large dimensioning of the projections and the

associated recess (s) allows, whereby a correspondingly advantageous rotation between the outer ring of the pivot ring of the bearing bush can be realized.

According to a further preferred embodiment of a steering gear according to the invention can be provided that the one- or multi-part bearing bush made of one or more plastics (preferably fiber reinforced, in particular with a fiber filling of 30% to 50%) and then in particular as an injection molding, optionally as a multi-component injection molded part , or of one or more metals, in particular light metal (s), preferably aluminum, then in particular as a die-cast part, is formed. This allows advantageous manufacturability for the fixed bearing and thus for a steering gear according to the invention as a whole. Farther For example, production of the bearing bush made of one or more plastics can also have an advantageous effect on the weight of a corresponding steering gear.

By contrast, the swiveling ring can preferably be made of metal, in particular of

Spring steel, and continue to be preferably integrally formed.

The guide opening of the already described and preferably in one

According to the invention provided steering gear movable bearing can be formed both as a one-sided open guide channel (i.e., as a guide groove) as well as in the circumferential direction completely closed guide opening.

In accordance with an embodiment of such a movable bearing, which is particularly advantageous in terms of its construction, it can also be provided for achieving the described functionality that

 - The floating bearing sleeve with the guide element (preferably directly) is connected (at least such that a relative movement in the direction of the longitudinal axis of the guide member and tilting about an axis parallel to the longitudinal axis of the floating bearing sleeve axis is prevented, preferably a completely immovable connection is provided) and a from the longitudinal axis of the floating bearing sleeve radially spaced portion of the guide element in a extending in a radial direction with respect to the longitudinal axis of the floating bearing sleeve

 Guide opening of the holding element is guided axially movable, or

 - The guide element is connected to the holding element and at least one radially spaced from the longitudinal axis of the floating bearing portion of the

Guiding element in at least one in a radial direction with respect to the longitudinal axis of the floating bearing sleeve extending guide opening of the floating bearing sleeve (or an element connected to the floating bearing sleeve element) is guided axially movable. The guide element can be immovably connected on the one hand with the holding element, in which case, as in the embodiment according to the first alternative, the tilting of the guide element in the guide opening is realized in that the guide element is connected to the holding element decentralized with respect to the longitudinal axis of the floating bearing sleeve or cooperates. As a result, caused by a load of the screw pinion shaft with a torque pivoting about the axis of rotation of the fixed bearing leads to a slight rotation of the floating bearing sleeve or part thereof about its longitudinal axis, so that then adjusts an inclination of the bearing pin within the guide hole. On the other hand, the guide element can also pivotable (at least about an axis, preferably parallel to the

 Longitudinal axis of the floating bearing sleeve extends) to be connected to the holding element, in which case the loose bearing sleeve should be additionally secured against rotation about its longitudinal axis, to tilt the bearing pin within the

 Guiding opening to ensure a load of the screw pinion shaft with a torque. Such a backup of the floating bearing sleeve against rotation about its longitudinal axis can preferably be achieved in a steering gear according to the invention in that it is at least rotationally fixed and in particular integrally formed with the bearing sleeve for the fixed bearing of the steering gear. The pivotable connection between the guide element and the holding element can be based both on a rotary joint and on an elastic deformation (for example of the guide element).

According to a preferred embodiment of the movable bearing preferably encompassed by a steering gear according to the invention, provision can be made for the longitudinal axis of the guide element to be radial with respect to the longitudinal axis of the guide element

Floating sleeve runs and this thus cuts. As a result, a symmetry in terms of the realization of a terminal stop acting and consequently a (in particular minimal) pivoting of the pinion shaft about the pivot axis can be achieved, for both directions of rotation, with which the pinion shaft of the

Steering motor is driven, essentially the same size.

Incidentally, the invention also relates to a steering system which has at least one

According to the invention steering gear and a rotationally driving connected to the pinion shaft steering motor comprises. The gear of the steering gear can also be rotatably or rotationally drivingly connected to a steering shaft, in particular a steering column, the steering system. The steering system according to the invention can be designed in particular as a power steering system, by means of the steering motor, a supporting torque can be generated so that one of a driver of a power steering system comprehensive motor vehicle on the steering column for steering the motor vehicle to be applied steering torque (possibly temporarily up to zero) is reduced. Alternatively, it is also possible to design the steering system in such a way that the entire steering torque required for steering is generated by the steering motor (always).

Furthermore, the invention relates to a motor vehicle with a steering system according to the invention. The indefinite articles ("a", "an", "an" and "an"), in particular in the patent claims and in the claims generally explaining

Description, are to be understood as such and not as number words. Corresponding to this concretized components are thus to be understood that they are present at least once and may be present more than once.

The invention will be explained in more detail with reference to exemplary embodiments illustrated in the drawings. In the drawings shows:

1 shows a longitudinal section through an inventive steering gear according to a first embodiment;

Fig. 2: a storage device of a fixed bearing and a pinion shaft of

 Steering gear according to Figure 1 in a perspective view.

FIG. 3 shows the bearing device and the pinion shaft according to FIG. 2 in a front view; FIG.

Fig. 4: a pivot ring of the bearing device according to FIGS. 2 and 3 in one

 Front view;

5 is a perspective view of a bearing device for a fixed bearing of a steering gear according to the invention according to a second

 Design shape;

FIG. 6 shows the bearing device according to FIG. 5 in a view from the front; FIG.

7 shows a longitudinal section through the bearing device along the cutting plane

 VII-VII in Fig. 6; and

8 shows a longitudinal section through the bearing device along the sectional plane

 VIII - VIII in FIG. 6.

Fig. 1 shows the essential components of an inventive

Steering gear. This comprises a housing 1, within which a gear 2 and a meshing with the gear 2 pinion 3 are rotatably arranged in the form of a Schraubritzels. The pinion 3 and the pinion 3 comprehensive (screw) pinion shaft 4 are integrally formed in the form of a worm. The gear 2 is fixedly mounted on an output shaft 5 of the steering gear. This output shaft 5, which has a toothing for a secure rotationally fixed connection with the gear 2 in the illustrated embodiment, for example, with a trained at least in one section as a rack handlebar, whereby the rack performs a translational movement in a known manner via Radlenkhebel ( not shown) in a pivoting movement of steerable wheels (not shown) of the motor vehicle can be translated. In the output shaft 5 may also be a steering column of a power steering system, which is connected to a steering wheel and a steering pinion on the

Handlebar acts.

The pinion shaft 4 has a drive-side end over which this with the

Output shaft of a steering motor (not shown, for example, an electric or

Hydraulic motor) is connectable. In the region of this drive-side end, the pinion shaft 4 is mounted in the housing 1 by means of a first bearing. These

Bearing is designed as a fixed bearing 6, which allows a pivoting of the pinion shaft 4 about a pivot axis 7 (see Fig. 2 to 4). This pivot axis 7 extends in FIG. 1 perpendicular to the plane of the drawing. Such a pivoting causes a deflection of the drive-side end opposite end of the pinion shaft 4, which is mounted there by means of a movable bearing 8 within the housing 1. This floating bearing 8 is designed so that it allows the resulting from the pivoting of the pinion shaft 4 deflection of this end of the pinion shaft 4.

Both the fixed bearing 6 and the movable bearing 8 each comprise a rotary bearing 9 in the form of a ball bearing. In inner bearing rings 10 of this pivot bearing 9, the corresponding portions of the pinion shaft 4 are supported, while outer bearing rings 11 of the pivot bearing 9 are mounted in a respective bearing device 12, 13, which are in turn received within the housing 1. The storage devices 12, 13 are structurally designed so that in the case of the fixed bearing 6 u.a. the pivoting of the pinion shaft 4 about the pivot axis 7 and in the case of the movable bearing 8 allow the deflection of the free end of the pinion shaft 4.

For this purpose, the bearing device 12 of the fixed bearing 6 comprises a bearing sleeve 14 with annular cross-sections, the inner side in a first longitudinal section, the associated pivot bearing 9 and in a second longitudinal section 16 receives an inner ring 16 of a pivot ring. This inner ring 16 of the pivot ring 15 and the outer bearing ring 1 1 of the pivot bearing 9 of the fixed bearing 6 are interposed an annular disc 17 secured axially supported within the fixed bearing sleeve 14, wherein the inner ring 16 of the pivot ring 15 with the interposition of the annular disc

17 on the one hand to the outer bearing ring 1 1 of the pivot bearing 9 and on the other hand to a first circumferential shoulder, of an annular, on the

corresponding end of the bearing sleeve 14 axially adjacent stop ring disc

18 is formed, supports. In the same way, the distal of the inner ring 16 of the pivot ring 15 side of the outer bearing ring 1 1 of the pivot bearing 9 at a second, circumferential shoulder, which is formed by the fixed bearing sleeve 14 at the corresponding axial end, supported.

The swivel ring 15 comprises, in addition to the inner ring 16, an outer ring 19.

This outer ring 19 is connected to the inner ring 16 via two torsion webs 20 (compare FIGS. 3 and 4). The outer ring 19, the inner ring 16 and the torsion bars 20 are integrally formed from, for example, spring steel.

The two torsion bars 20 define the position of the pivot axis 7, about which the outer ring 19 is pivotable relative to the inner ring 16 of the pivot ring 15. The torsion bars 20 of the pivot ring 15 not only allow pivoting of the outer ring 19 to the inner ring 16 and thus the pinion shaft 4 relative to the gear 2 and to the housing 1, but at the same time cause the spring force by which the pinion 3 in the toothing of the Gear 2 is pressed in order to achieve the lowest possible backlash and thus the lowest possible noise during operation of the steering gear, especially in a Wechsellenken. This spring force results from the fact that during assembly of the steering gear, the pinion shaft 4 is deflected so far as a result of contact with the gear 2, that sufficient twisting of the torsion bars 20 results, whereby the elastic restoring moments resulting from this twisting of the torsion bars 20, Counteract the deflection of the pinion shaft 4 and thus act against the gear 2.

An axial position securing the inner bearing ring 10 of the pivot bearing 9 of the fixed bearing 6 on the pinion shaft 4 as well as the arranged within the bearing sleeve 14 components takes place with the interposition of a voltage applied to the inner bearing ring 10 thrust piece 21 by means of a screw 22 in an internal thread, the in the drive-side end of the pinion shaft 4 is integrated, is screwed. A bearing of the outer ring 19 of the pivot ring 15 and thus the entire bearing device 12 of the fixed bearing 6 within the housing 1 by means of a bearing bush 23 which has an annular portion 24, in which the outer ring 19 of the pivot ring 15 is embedded, and two diametrically opposite of The annular portion 24 extending bearing pin 25 includes. The cylindrical bearing pin 25, whose longitudinal axes 26 are aligned perpendicular to the pivot axis 7 and which intersect these, are in matching, ie with a minimal oversize, dimensioned, cylindrical bearing mounts 27 of

Housing 1 rotatably mounted. The longitudinal axes 26 of the position pins 25 thereby correspond to an axis of rotation 28 about which the outer ring 19 of the pivot ring 15 and thus the entire bearing device 12 of the fixed bearing 6 and the bearing therein

Pinion shaft 4 in narrow limits, which are defined by the floating bearing 8, are pivotable. This rotation axis 28 intersects not only the pivot axis 7 but also the longitudinal or rotation axis 29 of the pinion shaft 4. Unlike a pivoting of the pinion shaft 4 about the pivot axis 7 pivoting about the rotation axis 28 does not lead to an elastic restoring moment.

As is apparent in particular from FIGS. 1 and 4, extending from the

Outer ring 19 of the pivot ring 15 in a diametrical arrangement two approximately rectangular projections 30, each extending into one of the bearing bush 23 formed by the bearing pin 25 and engage there in a corresponding recess formed, which are embedded in the material of the bearing pin 25. The bearing pin 25 and the entire bearing bush 23 is made of a

Plastic formed, for a manufacture of the storage device 12 u.a.

It can be provided that the outer ring 19 of the pivot ring 15 by means of the intended for the formation of the bearing bush 23 plastic in the context of a

Injection molding process is overmoulded. Alternatively, it can be provided that the

Bearing bush 23 is formed of aluminum and two split along a radial plane halves, which are assembled after insertion of the outer ring 19 of the pivot ring 15 and at least by fixing the bearing pin 25 in the bearing mounts of the housing 1 are fixed in position to each other. By the engagement of the projections 30 of the outer ring 19 of the pivot ring 15 in the

Recesses in the bearing pin 25 of the bearing bush 23 is formed a rotation, by which a relative rotation between the pivot ring 15 and the bearing bush 23 is prevented. The bearing device 13 of the movable bearing 8 comprises a floating bearing sleeve 31 with an annular cross-sectional area. Within a longitudinal section of the

Floating sleeve 31 is also designed as a ball bearing pivot bearing 9 is arranged, wherein the outer side of the outer bearing ring 1 1 of this pivot bearing 9 is in direct contact with the inside of the floating bearing sleeve 31. In a second longitudinal section of the floating bearing sleeve 31 and thus axially from the pivot bearing. 9

spaced within the floating bearing sleeve 31, a retaining ring 32 is arranged, which forms a shell opening, within which one end of a guide member 33 is arranged fixed. This guide element 33 extends outward from the retaining ring 32 in the radial direction, wherein it protrudes through a defined by oversize through hole in the floating bearing sleeve 30. In this case, the guide element 33 protrudes into a guide opening 34, which is formed by a holding element 35 immovably connected to the housing 1. The

The longitudinal axis 36 of the guide element 33 is aligned radially with respect to the longitudinal axis 29 of the floating bearing sleeve 31 and thus intersects it, wherein at the same time a substantially vertical orientation is provided. The longitudinal axis of a circular opening cross-section having and therefore cylindrical

Guide opening 34 is aligned parallel to the longitudinal axis 36 of the guide member 33 at unloaded steering gear. Furthermore, the opening cross-section or the diameter of the guide opening 34 is defined, albeit to a lesser extent, larger than the cross-sectional area or the diameter of the portion of the guide element 33 received therein, whereby u.a. an axial displaceability of the guide element 33 within the guide opening 34 is possible. As a result of this displaceability allows the movable bearing 8 in principle pivoting of the pinion shaft 4 about the fixed bearing 6 formed by the pivot axis 7, which extends as exactly as possible perpendicular (but spaced) to the longitudinal axis 36 of the guide member 33 of the floating bearing 8.

If the pinion shaft 4 is driven to rotate during operation of the steering gear in one of the two possible directions of rotation by means of the steering motor, this results not only in forces due to the toothing forces, the pivoting of the pinion shaft 4 (in Fig. 1 upward) under increasing elastic bias of Torsionsstege 20 of the fixed bearing 6 would cause the trained by these pivot axis 7, but also to a slight pivoting about the rotation axis 28. This pivotal movement is of the Schraubritzelwelle 4 on the pivot bearing 9 of Loslagers 8 and transferred from this to the floating bearing sleeve 31 and leads after a very short relevant deflection to a contact of the

Guide member 33 with the wall of the guide opening 34. Due to the only one-sided and eccentric support of the floating bearing sleeve 31 by means of abutting the wall of the guide hole 34 guide member 33 further pivoting the Schraubritzelwelle 4 about the rotation axis 28 then leads to a slight rotation of the retaining ring 32 attached to it

Guide element 33 within the floating bearing sleeve 31, whereby the guide member 33 is misjudged within the guide opening 34. Once this tilting is done, the movable bearing 8 prevents not only a further pivoting of the pinion shaft 4 about the rotation axis 28 but also about the pivot axis 7, so that for the corresponding pivotal movement of the pinion shaft 4, an end stop is formed. This end stop for a pivoting of the pinion shaft 4 about the pivot axis 7 thus directly depends on how far a pivoting of the Schraubritzelwelle 4 about the axis of rotation 7 perpendicular to the axis of rotation 28 is possible before the guide member 33 misjudged within the guide opening 34. This one

Pivotility of the pinion shaft 4 structurally largely can be dimensioned accurately and is substantially independent of the state of wear of the steering gear and possibly also the subsidence of the Schraubritzels 3 and the gear 2, due to the design of the floating bearing 8 a

Limitation realized for a pivoting of the pinion shaft 4 about the pivot axis 7, which at a load of the Schraubritzelwelle 4 by means of a torque, i. during operation of the steering gear, also independent of this wear and possibly also subsidence state and is particularly directly effective when the pinion shaft 4 is loaded by a torque, or becomes effective before the forces generated by the load of the Schraubritzelwelle 4 opposite forces, which result from the springing by means of the fixed bearing 6, overcompensate, so that thereby caused pivoting the

Pinion shaft 4 about the pivot axis 7 during operation of the steering gear through the

Floating bearing 8 is prevented.

The floating bearing 8 thus causes in principle and during the entire service life of the steering gear largely or completely prevented pivoting of the pinion shaft 4 about the pivot axis 7, provided that the pinion shaft 4 is loaded during operation of the steering gear with a torque, so that a minimal

Basic game or sets in this regard a broadest freedom of play. This in turn allows that even with a relatively weak bias (torsion) of the torsion bars 20 of the fixed bearing 6 a sufficient springing of the pinion shaft 4 can be ensured against the gear 2, whereby a

Unwanted noise behavior, especially in a Wechsellenken can be avoided. At the same time, temperature-induced strains and

Geometry changes due to a water absorption in plastic elements are always compensated when the pinion shaft 4 is not loaded with a torque (ie when the steering system of the motor vehicle does not perform steering movement), because then by the floating bearing 8, a pivoting of the pinion shaft 4 about the pivot axis 7 is possible. Thereby, an undesirably high friction in particular of the toothing, which is formed between the screw pinion 3 and the gear 2, can be avoided.

The steering gear further comprises a connecting element 37, which the

Fixed bearing sleeve 14 connects to the floating bearing sleeve 31 and this is integrally formed and the same material with the bearing sleeves 14, 31. As is apparent from FIGS. 1 and 2, the connecting element 37 is tubular with annular or part-circular cross-sections, this having a jacket opening 38 which is arranged in a central portion of the connecting element 37 and which extends over a portion of its circumference extends. Through this

Shell opening 38, a portion of the gear 2 in which of the

Connecting element 37 limited and the pinion shaft 4 in the u.a. the pinion 3 forming portion projecting inner volume protrude to allow engagement of the teeth of the gear 2 and the pinion 3.

By means of the connecting element 37 is effected on the one hand, that the elastic restoring moments resulting from the torsion of the torsion bars 20 of the pivot ring 15 of the fixed bearing 6 are not transmitted exclusively via the pivot bearing 9 of the fixed bearing 6 on the pinion shaft 4, resulting in a relatively high Tilting load of this pivot bearing 9 would be connected. Rather, these are elastic

Return torques transmitted primarily via the fixed bearing sleeve 14 of the fixed bearing 6 and the connecting member 37 integrally connected therewith and on the floating bearing sleeve 31 on the pivot bearing 9 of the movable bearing 8. On the other hand, by the

Connecting member 37 prevents relative rotation between the fixed bearing sleeve 14 and the floating bearing sleeve 31 about the longitudinal axes 29. 5 to 8 show an alternative embodiment of a bearing device 12 for a fixed bearing 6 of a steering gear according to the invention, in particular a steering gear, as it is otherwise shown in FIG. 1.

The bearing device 12 according to FIGS. 5 to 8 in turn comprises a bearing sleeve 14, wherein within the bearing sleeve 14 a pivot bearing 9 in the form of a ball bearing, an inner ring 16 of a pivot ring 15 and a support plate 39 are arranged. The inner ring 16 of the pivot ring 15 is in turn connected via two torsion bars 20, which extend through corresponding through holes 40 of the bearing sleeve 14, with an outer ring 19 of the pivot ring 15. The outer ring 19 of the pivot ring 15 is cup-shaped and thus comprises a radially extending portion 41 and an axially extending, tubular portion 42 with an annular cross-section. The tubular portion 42 extends from the side facing away from the pivot bearing 9 side of the radially extending portion 41 of the outer ring 16 of the pivot ring 15. In the region of the tubular portion 42, the wall of the outer ring 16 of the pivot ring 15 forms two diametrically opposed through holes, in each case one

Bearing pin 25 is received fixed. The bearing journals 25 project beyond the outer side of the wall of the outer ring 16 of the swivel ring 15. It is provided that the trunnions 25 with these sections are designed accordingly

Bearing mounts 27 of a housing 1 of the steering gear engage to the

Rotation of the bearing device 12 with respect to a rotation axis 28 which is arranged perpendicular to the pivot axis 7, to ensure, as shown in a corresponding manner for the steering gear according to FIGS. 1 to 4.

To produce the bearing device 12 according to FIGS. 5 to 8, it is provided to provide a tubular workpiece for forming the fixed bearing sleeve 14 and to form a first axial stop, specifically the abutment adjacent to the rotary bearing 9, by forming a first end section of the workpiece that this end portion projects radially inwards. Subsequently, the pivot bearing 9, the inner ring 16 of the pivot ring 15 and the support plate 39, starting from the still open, ie not yet forming an axial stop end inserted into the bearing sleeve 14. Thereafter, a second axial stop is formed by forming the other end portion of the workpiece and thereby received within the fixed bearing sleeve 14 components, ie, the outer bearing ring 11 of the pivot bearing 9 and the entire pivot bearing 9, the Inner ring 16 of the pivot ring 15 and the entire pivot ring 15 and the support plate 39, axially secured.

The turn preferably integrally and further preferably formed of spring steel pivot ring 15 of the bearing device 12 of FIGS. 5 to 8 may also be prepared by a forming, for example by deep drawing, and in connection with a punching.

The fixation of the bearing pin 25 within the passage openings of the wall of the outer ring 19 of the pivot ring 15 is preferably selected insoluble and can in particular cohesively, for example by welding, soldering or gluing done. Non-positive (for example by means of a press fit) and

positive locking (eg by means of a screw), then possibly also releasable, connection variants are also possible.

LIST OF REFERENCES

1 housing

 2 gear

 3 screwdrivers

 4 screw pinion shaft

 5 output shaft

 6 fixed storage

 7 pivot axis

 8 floating bearings

 9 pivot bearings

 10 inner bearing ring of a pivot bearing

 1 1 outer bearing ring of a pivot bearing

 12 storage facility of the fixed storage

 13 bearing device of the floating bearing

 14 fixed bearing sleeve

 15 swivel ring

 16 inner ring of the swivel ring

 17 ring disk

 18 stop ring disc

 19 outer ring of the swivel ring

 20 torsion bar

 21 pressure piece

 22 screw

 23 bearing bush

 24 annular portion of the bearing bush

25 journals

 26 longitudinal axis of a journal

 27 bearing seat of the housing

 28 axis of rotation

 29 longitudinal axis of the pinion shaft / bearing sleeves

30 projection of the outer ring of the pivot ring

31 floating bearing sleeve

 32 retaining ring

 33 guide element

34 guide opening retaining element

Longitudinal axis of the guide element

connecting element

Shell opening of the connecting element

support disc

Through opening of the fixed bearing sleeve

radially extending portion of the outer ring of the pivot ring

axially extending, tubular portion of the outer ring of the pivot ring

Claims

claims: 1. steering gear for a steering system of a motor vehicle with  a housing (1),  a gear (2),  - One with the gear (2) meshing pinion (3) and  a pinion shaft (4) comprising the pinion (3),  wherein the pinion shaft (4) on one side of the pinion (3) in a fixed bearing (6) is mounted, which comprises a pivot bearing (9) in which the pinion shaft (4) is accommodated and which is received in a bearing sleeve (14) and wherein the fixed bearing (6) further comprises a pivot ring (15) having an outer ring (19) and an inner ring (16) pivotally about one or more torsion bars (20) about one or more  Torsionsstege (20) defined pivot axis (7) are interconnected, wherein the inner ring (16) is received in the fixed bearing sleeve (14) and the outer ring (19) is mounted within the housing (1), characterized  in that the outer ring (19) of the swivel ring (15) is mounted rotatably about a rotational axis (28) located transversely to the swivel axis (7) within the housing (1). 2. Steering gear according to claim 1, characterized in that the  Outer ring (19) of the pivot ring (15) has two bearing pins (25) or  Has bearing mounts whose coaxial longitudinal axes (26) of the axis of rotation (28) correspond. 3. Steering gear according to claim 1, characterized in that the  Outer ring (19) of the swivel ring (15) in a bearing bush (23)  is received, the two bearing pins (25) or bearing mounts whose coaxial longitudinal axes (26) of the axis of rotation (28) correspond. 4. Steering gear according to claim 2 or 3, characterized in that the bearing pins (25) are each rotatably received within a bearing receptacle of the housing (1) or in each case a bearing journal of the housing (1) in the bearing mounts. 5. Steering gear according to one of claims 2 to 4, characterized in that the outer ring (19) of the swivel ring (15) and / or the bearing bush (23) a tubular portion (42) on which the bearing pins (25) or bearing receptacles are arranged. 6. Steering gear according to claim 5, characterized in that the  Bearing journals (25) are received as separate components in each case in an opening or recess of the tubular portion (42). 7. Steering gear according to claim 3 or one of the dependent of claim 3 claims, characterized in that the outer ring (19) of the  Swing ring (15) forms a projection (30) which engages in a recess of the bearing bush (23) such that a rotation between the outer ring (19) of the swivel ring (15) and the bearing bush (23) with respect to a relative rotation about the axis of rotation of Turning bearings (9) of the fixed bearing (6) train. 8. Steering gear according to claim 7, characterized in that the projection (30) of the outer ring (19) of the pivot ring (15) extends into one of the bearing pin (25). 9. Steering gear according to claim 3 or one of the dependent of claim 3 claims, characterized in that the bearing bush (23) from  Plastic or metal is formed. 10. Steering gear according to one of the preceding claims, characterized  characterized in that the pinion shaft (4) is mounted on the other side of the pinion (3) in a floating bearing (8) comprising a pivot bearing (9) having an inner bearing ring (10) in which the Schraubritzelwelle is received, and an outer bearing ring (1 1), which is integrated in a floating bearing sleeve (31) comprises, wherein the floating bearing sleeve (31) with a guide element (33) and the guide element (33) with a holding element (35) for fixed integration within the housing (1) of the steering gear is provided, such interaction that the floating bearing sleeve (31) in a first direction, the radial with respect to the longitudinal axis (29) of the floating bearing sleeve (31) and also perpendicular to the of the fixed bearing (6) formed pivot axis (7) is movable relative to the holding element (35), when the pinion shaft (4) is not loaded with a torque, while such relative movement is prevented when the pinion shaft (4) with a Torque is loaded by then the floating bearing sleeve (31) in a second Direction, which is also radially with respect to the longitudinal axis (29) of the floating bearing sleeve (31) and also aligned perpendicular to the first direction, relative to the holding element (35) is moved, whereby the guide element (33) in a guide opening (34) of the holding element (35) or the floating bearing sleeve (31) tilted.