WO2017080844A1

WO2017080844A1 - Method for producing an integrally bonded joint, and connection arrangement

Info

Publication number: WO2017080844A1
Application number: PCT/EP2016/076017
Authority: WO
Inventors: HEITZ Thomas DR.; Sebastian Regner
Original assignee: Thyssenkrupp Presta Ag; Thyssenkrupp Ag
Priority date: 2015-11-09
Filing date: 2016-10-28
Publication date: 2017-05-18
Also published as: DE102015221986A1

Abstract

The present invention relates to a method for producing an integrally bonded joint between two parts (2, 3) to be joined, in steering systems, which have joining surfaces (25, 33) opposing one another and bordering a joint gap (6), wherein a viscous adhesive (51) is introduced into the joint gap (6), which adhesive forms a solid adhesive connection after hardening, wherein the first of the joining parts (3) has a joining section (32) with a rotationally symmetrical cross-section with an outer peripheral surface, which forms the first joining surface (33), and the second of the joining parts (2) has an opening (24) with a rotationally symmetrical opening cross-section with an inner peripheral surface, which forms the second joining surface (25), wherein the joining section (32) of the first joining part (3) is arranged with a radial clearance (S) coaxially inside the opening (24) of the second joining part (2), and the joining gap (6) is formed between the first and the second joining surface (33 and 25), which joining gap has a radial width (B) which corresponds on average to half the radial clearance (S/2). So as to facilitate an improved positioning of the bonding parts (2, 3), in particular a simplified coaxial alignment of the joining sections (24, 32), and to improve the adhesive connection the invention proposes that the adhesive is filled with solid particles (7).

Description

Method for producing a material-fit joint connection

and connection arrangement

State of the art

The invention relates to a method for producing a cohesive joint connection between two parts to be joined, in steering systems, the opposing, a joint gap delimiting joining surfaces, wherein in the joint gap, a viscous adhesive is introduced, which forms a solid adhesive bond after curing, wherein the first of the Fügeteile a joining portion having rotationally symmetrical cross-section having an outer peripheral surface which forms the first joining surface, and the second of the joining parts has an opening with rotationally symmetrical opening cross section with an inner peripheral surface which forms the second joining surface, wherein the joining portion of the first joining part with radial clearance coaxially within the Opening of the second joining part is arranged, and is formed between the first and second joining surface of the joint gap, which has a radial width which corresponds on average to half the radial clearance. Furthermore, the invention relates to a steering shaft with a connection arrangement.

It is known to connect torque-transmitting two components for torque transmission by an adhesive connection. This type of cohesive connection is used for example in shaft-hub connections. The adhesive connection takes place between see a rotationally symmetrical, for example, cylindrical joint portion of a first joining part, such as a trained as a shaft component, and a corresponding thereto, also rotationally symmetrical, for example, cylindrical opening of the second joining part. The first joining section has a smaller cross section, for example a diameter of a cylindrically shaped joining section, which is smaller than the opening cross section of the opening of the second joining part, for example the diameter of a cylindrical opening. The difference between the cross sections or diameters corresponds to the radial play between the joining sections. As a result, the first joining section can be arranged coaxially within the opening, wherein a clearance-symmetrical joining gap which is coaxially aligned with respect to the joining sections can also be formed by the clearance between the joining surfaces which are opposite each other in the radial direction. In the case of cylindrical joining sections, the joint gap thus has the shape of a thin-walled hollow cylinder whose width in the radial direction corresponds to half the game on average.

The cohesive connection is made by first introducing into the joint gap adhesive which, in the uncured state, usually has the consistency of a highly viscous liquid, i. a viscous mass. The introduction of the adhesive can be carried out, for example, by coating the first joining section designed as a cylindrical shaft section with the adhesive and then inserting it in the axial direction into the second joining section designed as an opening until the axial position of the joining connection has been reached. The adhesive is taken in the axial direction in the joint gap and fills this substantially completely. After setting or hardening the adhesive adheres firmly to both joining surfaces and thus causes the cohesive connection of the joining sections. Alternatively or additionally, the adhesive may be applied to the mating surface on the inner peripheral surface of the opening prior to insertion of the shaft, or the mating portions are coaxially positioned in the mating position and the adhesive is injected into the joint gap or vacuum impregnated.

Such an adhesive bond has the advantage that the joining surfaces can be brought into the axial joining position free of radial stresses, since the first liquid-viscous adhesive filling the joint gap can axially escape from the joint gap and thus no radial pressure on the inner peripheral surface or the outer peripheral surface is exercised. Therefore, such a joint connection is preferably used in lightweight construction, if at least one of the joining parts is made of lightweight material, which should not be permanently under radial tension, as would be the case for example with axial pressing without play. In addition, it is avoided that the surface of fiber composites is damaged uncontrollably with play-free pressing. Therefore, an adhesive bond is preferred in order to fix a for example made of light metal such as aluminum, magnesium, steel or titanium yoke with its axial opening on a CFK tube (carbon fiber reinforced plastic) existing steering shaft portion of a motor vehicle steering system torque-locking. The disadvantage, however, is that a permanent adhesive bond of joining parts of different materials can not be realized and that most adhesives require long curing times. Another disadvantage is that not all materials are good for a pure adhesive bond are suitable because the adhesion is often unsuitable to transmit large forces or torques.

In view of the above-described problem, it is an object of the present invention to provide an adhesive method of the type mentioned, which allows an improved joining of the joining parts.

Next, a steering shaft to be provided with a connection arrangement, which is durably represented as an adhesive bond. Presentation of the invention

The object is achieved by a method having the features of claim 1. Advantageous developments of the invention are shown in the subclaims.

According to claim 1 1, a steering shaft according to the invention is provided.

To solve the above problem, the invention proposes that the adhesive is filled with separate solid particles.

The adhesive used forms a viscous, viscous mass when uncured in the raw state, with masses of solids insoluble therein, i. solid grains or bodies, evenly filled, which are also referred to as filler particles. The solid particles are added to the adhesive as a powder, which is uniformly mixed with the adhesive composition, so that the relative number of particles per volume of the adhesive is the same on average. As an adhesive, for example, an epoxy resin hardener system can be used, wherein the properties of the filler particles are specified according to the invention so that there are particular advantages in the underlying, specific joining situation.

In the manufacture of the joint, the adhesive is applied to at least one of the joining surfaces, and then the joining surfaces are formed to form the joint gap by the one joining portion is inserted axially into the opening of the other joining portion. The solid particles contained in the adhesive perform a relative movement to the surfaces of the joining surfaces. When the solid particles come into contact with one of the surfaces, they cause a three-dimensional plastic deformation or a local cutting operation on the joining surface, in the form of grooves or scratched or crushed groove-like depressions or projecting protrusions. In particular, the local depressions should be formed in the joining surface undercut in the loading direction. The resulting structuring or profiling The joining surfaces is embedded in the adhesive and causes after curing additionally a positive connection with the hardened in the joint gap adhesive application. The solid particles themselves and preferably the cured adhesive form a kind of form-fitting elements between the joining surfaces with which they engage with the aforementioned recesses. In addition, the solid particles can act as spacers or spacer elements in the joint gap: The solid particles support the joint portion in the radial direction against the joining surface on the inner wall of the opening in the radial direction. The selected adhesive or mixture of adhesive and solid particles is preferably a high viscosity or putty type adhesive that can fill and bridge a joint gap. Thereby, the width of the joint gap in the uncured, viscous state of the adhesive can not be reduced below the size of the solid particles, so that the solid particles can be brought during the joining operation by relative movement of the joining surfaces between the joining surfaces. Furthermore, an improved coaxial centering of the joining sections can be achieved. By supporting in the joint gap by means of the solid particles, an outer support for centering can be omitted, whereby the production cost is reduced. The width of the joint gap is evened out over the circumference, which benefits the strength of the adhesive bond.

It may be advantageous for at least some of the solid particles to have a particle size at least equal to the average width of the joint gap. The grain size of the solid particles is specified in relation to the width of the joint gap. As explained above, the width of the joint gap is limited by the radial play between the joining sections, which can move in the event of a not exactly coaxial alignment over the circumferential course between zero and the cross-sectional difference. In the method according to the invention, the solid particles are introduced into the joint gap in a statistically uniform distribution. In this case, the solid particles form a kind of radial spacers or spacers between the mutually facing joining surfaces, which means that the joining surfaces abut the intermediate solid particles from both sides, so that the width of the joint gap is correlated with the mean grain size of the solid particles. Characterized in that the size of at least a portion of the solid particles is set equal to half the radial clearance, they can spread over the circumference only in a single layer in the joint gap and thus keep the joining surfaces over the entire circumference continuously at a uniform radial distance in thickness the layer to each other. The width of the joint gap is precisely defined in this way over the entire circumference by the solid particles to half the game, so that no desaching of the joint sections can occur. About the axial extent of the joining surfaces are also supported by the solid particles against each other, so that a mutual tilting of the longitudinal axes of the joint Gections also can not occur. Thanks to the use according to the invention of the solid particles as internal spacers or spacer elements between the joining surfaces, an automatic coaxial alignment, ie centering of the joining parts, takes place when the joining sections are brought into axial overlap, ie, one joining section axially into the opening of the other Inserting section is inserted. The coaxial centering is ensured until the adhesive has hardened to form a solid cohesive connection, without any external support of the joining parts being required. This simplifies manufacture. By the invention it is possible to adjust the width of the joint gap by introducing solid particles with a grain size that corresponds to half the game, consistently evenly and accurately to half the radial clearance. Thereby, the uniformity of the adhesive application between the joining surfaces is improved, whereby the durability and resilience of the adhesive bond is increased. The method eliminates the need for expensive external support, making it simpler and less expensive to implement. In addition, the accuracy of coaxial alignment is improved.

An embodiment of the invention provides that the solid particles at least partially have a greater hardness than the joining parts in the region of the joining surfaces. Hard particles, for example hard materials such as corundum, boron carbide or the like, which have a greater hardness than metal or plastic materials, can be used as solid particles, for example. This results in the advantage that the solid particles can not be deformed by the joining surfaces during assembly in the joint gap, and thus the function of the invention as spacer elements is retained in each case.

In addition, hard material particles can take on a further function in the method according to the invention, namely as a kind of means (tool) integrated into the adhesive for processing the joining surfaces. If hard particles are introduced into the joint gap and moved relative to the joining surfaces, either parallel or perpendicular to the joining surfaces, they touch or dig into the surfaces, causing local plastic deformation and / or cutting profiling or separation of the joining surfaces. As a result, a three-dimensional structuring of the surface with indentations and formations of the joining surfaces is formed, which are embedded in a form-fitting manner in the adhesive after hardening or setting. By this structuring or profiling on the one hand, the active adhesive surface is increased, on the other hand, the joining surfaces are connected via the adhesive layer not only cohesively, but also form-fitting manner. As a result, the load capacity of the adhesive connection is increased. The above-described structuring or profiling of the surfaces of the joining surfaces by means of hard material particles distributed in the adhesive can be carried out particularly effectively and with little effort in accordance with the following method steps:

Applying an adhesive to at least one of the joining surfaces, which is filled with separate solid particles (7),

and

- Coaxial positioning of the joining parts relative to each other outside of the joining gap, then:

- Moving the joining parts relative to each other at each other in the joining gap opposite joining surfaces in at least one extension direction of the joining surfaces and finally -Positioning the two joining parts in a desired joining position.

The adhesive, together with the evenly distributed hard particles, is applied to one or both joining surfaces, where it adheres as a thin adhesive layer. The adhesive can be applied before the parts to be joined are positioned outside the joining gap. By this is meant that the joining sections are arranged coaxially relative to one another but at an axial distance from one another, so that the joining surfaces do not overlap in the axial direction, i. initially not facing each other in the joint gap. It is also possible to first position the joining parts coaxially with one another and to apply the adhesive in this arrangement. Subsequently, the joining parts are moved toward one another in the axial direction, so that the joining section of the wave-shaped, preferably cylindrical first joining section is introduced into the opening forming the second joining section. After entering the joining section in the opening, the joining surfaces are moved parallel to each other along each other.

After the coaxial entry of the joining section into the opening, the joining surfaces which are then opposite in the joining gap are moved relative to one another on further insertion in the axial direction, wherein the adhesive layer is drawn into the joint gap in the axial direction, so that the hard material particles located therein are relative to both Joining surfaces are taken in the axial direction. Because the hard material particles according to the invention are at least as large as the width of the joint gap, they leave behind in the surfaces of the joining surfaces squeezed or incised groove or furrow-shaped indentations in the axial direction. In this way, an axial structuring in the form of a knurling or corrugation is formed, which is embedded in the adhesive layer and forms a solid positive connection with respect to a load in the circumferential direction after curing, in other words a torque-transmitting form-fitting Connection. The load capacity of the adhesive connection for torque transmission between the parts to be joined is thereby increased in an advantageous manner.

If the first joining section is located at least with an axial section within the opening of the second joining section, it can preferably be provided as a method step that the joining faces lying opposite in the joining gap are moved relative to each other in the circumferential direction. This is achieved simply by rotating the joining sections, which are at least partially coaxial with one another, about the common longitudinal axis. Subsequently, the two joining parts are brought into a desired joining position, that is the defined relative end position of the joining parts in the joint connection. As a result, the adhesive layer located in the joint gap is moved in the circumferential direction relative to both joining surfaces, and the hard material particles are also carried along in the circumferential direction. They squeeze or cut circumferentially at least partially circumferential, grooved or furc enförm ige formations in the surfaces of the joining surfaces. In this way, a structuring in the circumferential direction in the form of a knurling or corrugation is formed, which is filled by the viscous adhesive and forms a solid positive connection with respect to a load in the axial direction after curing. As a result, the tensile strength of the adhesive joint in the axial direction is advantageously increased.

It is particularly advantageous if the joining sections are moved relative to one another in the axial direction and in the circumferential direction with joining surfaces lying opposite one another in the joint gap. By combining the directions of movement can be incorporated into the joining surfaces in the circumferential direction and in the axial direction effective positive locking elements in the form of plastically molded grooves or grooves and shaped corrugations with projecting ridges. Thereby, the load capacity of the adhesive joint in the circumferential direction and in the axial direction can be increased. For practical implementation, it is conceivable first to bring the joining sections in the axial direction into the final joining position, in which the joining surfaces completely overlap axially, and in this axial position to rotate the joining parts about the common longitudinal axis. It may be advantageous that the amount of rotation is less than 360 °. As a result, the indentations and formations in the circumferential direction do not go through, so that the form-fitting effect of the axial direction in the longitudinal direction of the indentations and formations acting in the circumferential direction is not counteracted. The successive relative axial and rotational movements of the joining parts required for the realization can be made available with little effort in terms of production engineering. Alternatively, a sequence of stepwise relative movements of the joining sections in the axial and circumferential directions is also conceivable. As a result, steps and shapes running in steps on the joining surfaces can be realized. Another possible alternative provides that the joining sections are simultaneously moved in the axial direction relative to each other and rotated against each other. As a result, helical form on the joining surfaces circumferential indentations and indentations are formed, which do not intersect.

Preferably, the solid particles are formed as irregularly shaped grains. Irregularly shaped solid particles, in particular hard material particles, have the advantage that, in the above-described relative movements of the joining sections, they generally do not simply roll on the joining surfaces and thereby produce only slight deformations of the surfaces, but can get caught or wedged into the joint gap and become better and better cut deeper into the surfaces or pinch. As a result, an advantageous, deeper structuring or profiling of the joining surfaces can be achieved. This ensures a reinforced form-fitting effect and thus a higher load capacity of the adhesive bond. In addition, the hard particles are entrained safely in the joint gap when joining the parts to be joined. An irregular, sharp-edged form of the hard material particles can be realized by producing them as ground or broken fragments. For example, broken grains of corundum, silicon or boron carbide or the like hard materials can be used, which are used because of their extremely good abrasive properties as a grinding or polishing agent. In the method according to the invention, these properties benefit from the functionality when profiling the joining surfaces. The course of the structuring or profiling incorporated by means of the hard material particles can be adapted to the materials of the parts to be joined, the geometry of the joint gap and to the adhesive used.

In this regard, it may be advantageous that the grain size is greater than half the radial clearance between the joining sections. The grain size is the diameter of the smallest sphere in which the respective grain fits. The grain size may preferably be between 0.1% and 50%, more preferably between 1% and 10% greater than half the radial clearance (= the average distance) between the joining sections. If the grain size chosen to be greater than half the radial clearance, ie the average width of a uniform circumferential joint gap, cause the hard particles when introduced into the joint gap inevitably plastic deformation of the surfaces of the joint surfaces. Specifically, the hard particles are partially pressed into the surface and thereby produce indentations and formations in the form of knurls or corrugations, and cut partially groove or grooved depressions in the joining surfaces. It is advantageous that the structuring or profiling perpendicular to the surface of the joint surfaces can be formed deeper and shaped, whereby the strength of the adhesive bond can be increased.

It is furthermore advantageous that the hard material particles, which are larger than the average width of the joint gap, in each case interlock in the form of the form in the form of the embedded formations in the surfaces of the joining surfaces. As a result, in addition to the above-described functions for coaxial centering and for profiling or structuring of the joining surfaces, they can take on a further function as interlocking elements, which engage in a positive engagement with the profiling or structuring of the joining surfaces and thus positively lock them against one another, thereby increasing the load capacity and durability of the adhesive bond is further increased.

It is preferable if the solid particles have different grain sizes. In this case, preferably a mixture of grains with 30% volume fraction with grains having a grain size of less than 2% in relation to clearance or distance between the joining surfaces, and 20% -30% volume fraction with grains having a grain size of 2% to 7% of Game, as well as 20% -30% volume fraction with grains having a grain size of 7% to 25% of the game, as well as 5% -10% volume fraction with grains having a grain size of 25% to 50% of the game be incorporated into the adhesive.

It is preferably provided that the joining surfaces are formed in a cylinder jacket, i. the joining surfaces at least in sections have a circular cross-section. In this case, the radial clearance of the difference corresponds to the diameter of the joint sections and the opening. Alternatively or additionally, it is possible for the joining sections to be conical in sections. The game then designates the smallest relative distance of the conical surface to each other, so it is not measured radially, but inclined to the cone angle against the longitudinal axis

Further, a steering shaft is provided with a connection assembly comprising two joining parts, wherein the one joining part is a yoke and the other joining part is a shaft, wherein between the two joining parts, a joint gap is arranged, according to the invention in the joint gap a viscous adhesive as a connecting means is introduced and additionally separate solid particles are arranged in the joint gap. By a sharp-edged form of the solid particles, for example, grooved depressions can be formed, in which the adhesive can be distributed and thus creates a permanent joint connection of both joining parts. It is furthermore conceivable and possible for such an adhesive connection to be provided between other components of a steering device, for example between a steering pinion and a steering shaft, between an actuating lever and a clamping bolt and the like.

Particularly preferably, the joining parts are obtained by rapidly turning the one joining part, e.g. the shaft, in the other joining part, e.g. the yoke, interconnected. The rapid, repeated and steady movements of the shaft with respect to the fork cause heating of the adhesive. The increased temperature during the joining process allows a faster curing of the adhesive, so that the curing time can be shortened.

All of the individual features illustrated in the aforementioned individual embodiments of the invention may be combined and / or interchanged without departing from the scope of the invention. This includes in particular, but not exclusively, the design of the solid particles added to the adhesive.

Description of the drawings

Advantageous embodiments of the invention are explained in more detail below with reference to the drawings. In detail show:

FIG. 1 is a schematic perspective view of a motor vehicle steering system;

FIG. 2 shows a propeller shaft of the steering system according to FIG. 1,

FIG. 3 shows a perspective view of a steering shaft of the propeller shaft according to FIG. 2, FIG. 4 shows the steering shaft according to FIG. 3 in a sectional view along the longitudinal axis, in coaxial, axially pulled apart arrangement of the shaft section and the joint fork,

FIG. 5 shows the steering shaft according to FIG. 3 in a sectional view along the longitudinal axis, in the joining position of the joint fork on the shaft section, FIG. 6 shows the steering shaft according to FIG. 3 in a sectional view along the longitudinal axis, as in FIG. 4 in an alternative sequence of steps of the method,

Figure 7 is a schematic representation of a joining surface after the end of the joining operation according to Figures 4, and

8 shows the joint gap between the steering shaft and the yoke according to FIGS. 3,

4, 5, or 6 in a sectional view along the longitudinal axis.

Embodiments of the invention

In the various figures, the same parts are always provided with the same reference numerals and are therefore usually named or mentioned only once in each case.

Figure 1 shows a schematic perspective view of a motor vehicle steering system 100, wherein the driver via a steering wheel 102, a torque can be introduced as a steering torque in a steering shaft 1. The steering torque is transmitted via the steering shaft 1 to a steering pinion 104, which meshes with a toothed rack 106, which in turn transmits via corresponding tie rods 108 the predetermined steering angle to the steerable wheels 110 of the motor vehicle. The steering pinion 104 together with the rack 106, a steering gear 105. The steering gear 105 has a housing, not shown here, in which the steering pinion 104 is rotatable and the rack 106 is mounted longitudinally displaceable. An electric and / or hydraulic power assistance can be coupled in the form of an auxiliary power assistance 1 12, alternatively also a power assistance 1 14 or 1 16, either with the steering shaft 1, the steering pinion 104 and the rack 106. The respective power assistance 1 12, 1 14 or 1 16 enters an auxiliary torque in the steering shaft 1, the steering pinion 104 and / or an auxiliary force in the rack 106, whereby the driver is assisted in the steering work. The three different auxiliary power supports 1 12, 1 14 and 1 16 shown in FIG. 1 show alternative positions for their arrangement. Usually only one of the shown positions is occupied by a power assistance. The auxiliary torque or the auxiliary power, which is to be applied to assist the driver by means of the respective power assistance 1 12, 1 14 or 1 16, is determined taking into account the input torque determined by a torque sensor 1 18 in the auxiliary power assistance 1 12 or 1 14 can be arranged. The steering shaft 1 has an input shaft 10 connected to the steering wheel 102 and an output shaft 12 connected to the steering gear 104. The output shaft 12 is connected via a joint 2, which is designed as a universal or universal joint, with a shaft 3, which forms an intermediate shaft of the steering shaft 1 and the other via a similarly constructed joint 2 with an input shaft 1 19 of the steering gear 105th connected is. Figure 2 partially shows a portion of the steering shaft 1, namely a portion of the shaft 3, which is connected via a hinge 2 with the output shaft 12 or the input shaft 1 19.

The joint 2 comprises a joint fork 21 mounted on the shaft 3 coaxial with its longitudinal axis 31. The yoke 21 is connected in a conventional manner via a cross member 22 pivotally connected to a basically similar constructed second yoke 23, which is mounted on the output shaft 12 or the input shaft 1 19.

The shaft 3 is in the context of the invention, a first joining part, and the yoke 21, a second joining part, which is materially connected to the shaft 3, which is also referred to in this structure as a hybrid cardan shaft. The shaft 3 may preferably consist of a lightweight construction material in that it is designed, for example, as a CFRP pipe (CFRP = carbon fiber reinforced plastic). The yoke 21 may for example consist of a likewise lightweight, solid material, preferably a metal such as aluminum, magnesium or titanium.

The one end of the shaft 3 with the materially firmly attached in the joining position, ie glued joint fork 21 is shown in a perspective view in Figure 3. FIG. 5 shows the structure in a sectional view in the direction of the longitudinal axis 31. At its free end, the shaft 3 has a joining portion 32, which is cylindrical with an outer diameter d and a length I in the direction of the longitudinal axis 31. The cylinder jacket-shaped outer surface of the shaft 3 forms the first joining surface 33. The joint fork 21 has, as a joining section, an opening 24, which is formed as a circular bore with an inner diameter D. Their cylinder jacket-shaped inner surface 25 forms the second joining surface 25. The radial clearance S between the joining portion 32 and the opening 24 corresponds to the difference S = Dd. FIG. 4 shows the situation before assembly. Therein, the shaft 3 is aligned with its joining portion 32 with its longitudinal axis 31 coaxial with the opening 24 centered. In this illustration, prior to assembly, the joining portion 32 and the opening 24 are axially spaced from each other.

5

To carry out the method according to the invention, according to FIG. 4, an adhesive 51 is applied to the joining section 32, which radially over the circumference averages at least as thick as half the play, ie S / 2, or thicker. The adhesive 51 forms a highly viscous mass which adheres to the joining portion 32 and remains sufficiently stable for a relatively short period of time on the order of minutes during assembly in terms of dimensions and shape of the adhesive application 5.

FIG. 6 shows an alternative procedure in which the adhesive 51 is applied as adhesive application 5 to the joining surface 25 of the opening 24, that is to say the inner surface of the opening 24. Otherwise, the relative coaxial positioning of shaft 3 and yoke 21 is identical to the arrangement shown in FIG.

Starting from the coaxial positioning according to FIG. 4 or FIG. 6, the shaft 3 is moved axially toward the yoke 21 in the direction of the longitudinal axis 31 until the joining section 20 32 is positioned completely coaxially within the opening 24. Then, the joining surfaces 25 and 33 lie radially opposite one another and delimit between them a joint gap 6 which is cylindrical with a mean radial width B corresponding to half the clearance S, that is to say: B = S / 2 = (Dd) / second The joint gap 6 is completely filled by the adhesive 51 of the adhesive application 5.

25

FIG. 8 shows an enlarged sectional view of the joining gap 6 filled with the adhesive 51. It can be seen that solid particles 7 which are distributed uniformly over the volume are added to the adhesive 51. In the example illustrated, the solid particles 7 are in the form of hard grains, for example corundum grains which are harder than 30, the joining surfaces 33 and 25 of the joining section 32 and the opening 24. Preferably, the solid particles 7 and in particular the corundum grains are irregular and sharp-edged.

When inserting the shaft 3 in the opening, ie in the axial movement of position of Figure 35 in the joining position of Figure 5, the solid particles 7 are dragged axially with the adhesive application 5 and thereby move along the joining surfaces 33 and 25 along. The fact that the solid particles 7 consist of hard material, dig or squeeze They thereby engage in the joining surfaces 33 and 25, so that there radial recesses 71 arise which form a three-dimensional structuring or profiling with the remaining projections between them, and which are filled by the adhesive 51, so that they form fit in the adhesive application 5 are embedded. Corresponding to the axial longitudinal movement, the depressions likewise run in the direction of the longitudinal axis 31.

In FIG. 7, depressions 71 in the form of a scored or crimped scoring-like profile into the joint surface 25 of the joint fork 21 are shown by way of example. For clarity, the adhesive application was omitted in this view. At or after the axial insertion, which in Figure 4 with the arrow parallel to

Longitudinal axis 31 is indicated, the shaft 3 can be rotated relative to the opening 24 about the longitudinal axis 31. As a result, the solid particles 7 in the adhesive application 5 are moved in the circumferential direction with respect to the joining surfaces 33 and 25, so that they introduce depressions, as described above, into the joining surfaces 33 and 25, which extend in the circumferential direction in accordance with the rotational movement.

It is particularly advantageous if the shaft 3 during the insertion into the opening 24 alternately performs rotational and longitudinal movements, either in a predetermined sequence or even a stochastic method. As a result, a pattern of regularly defined or even irregularly arranged depressions 71 can be formed. The three-dimensional structuring of the surfaces formed thereby ensures that the joining surfaces 33 and 25, ie the surfaces of the joining section 32 and the opening 24 facing one another in the joint gap 6, are connected to one another in a form-fitting manner via the then solid adhesive application 5 after curing. The arrangement of the recesses in the axial (longitudinal) direction and in the circumferential direction increases the load capacity of the adhesive connection in the longitudinal direction and with respect to the transmission of torques.

An advantageous embodiment of the method according to the invention provides that at least part of the solid particles 7 is the same size as the width B of the joining gap 6, or larger. As a result, the solid particles 7 are arranged in the joint gap 6 in a single radial layer or position, wherein they abut against both joining surfaces 33 and 25. In the above-described insertion using relative rotational and longitudinal movements, the surfaces are particularly effectively provided with grooved - recessed or notched - wells, so that a tight fit with the adhesive application 5 is ensured. It is also advantageous that the solid particles 7 themselves act as interlocking elements between the joining surfaces 33 and 25, thus interlocking them in a form-fitting manner with one another by positive engagement in the indented depressions 71. In addition, the solid particles 7 provide for a centered support of the joining portion 32 in the opening 24 over the entire circumference, since the joint gap 6 is geometrically defined even with an imaginary distribution of at least three solid particles 7 of size B = S / 2 with constant circumferential width , As a result, an automatic centering of the joining portion 32 within the opening 24 takes place during insertion. Until curing of the adhesive 51 can thus account for no external centered support, whereby the production is simplified.

LIST OF REFERENCE NUMBERS

steering shaft

5 10 input shaft

12 output shaft

100 Motor vehicle steering system 02 Steering wheel

104 steering pinion

10 105 steering gear

106 rack

108 tie rod

1 10 wheel

1 12, 1 14, 1 16 Auxiliary assistance

15 1 18 Torque sensor

1 19 input shaft

2 joint

21 joint fork

22 cone cross

20 23 Joint fork

24 opening

25 joining surface

3 wave

31 longitudinal axis

25 32 Joining section

33 joining surface

d outer diameter

D inside diameter

length

30s game

5 adhesive application

51 adhesive

6 joint gap

B width

35 7 solid particles

71 wells

Claims

Method for producing a cohesive joint connection between two joining parts (2, 3) in steering systems which have opposing joining surfaces (25, 33) delimiting a joining gap (6), a viscous adhesive (51) being introduced into the joining gap (6). , which forms a solid adhesive bond after hardening,

wherein the first of the joining parts (3) has a joining section (32) with a rotationally symmetrical cross section with an outer peripheral surface which forms the first joining surface (33), and the second of the joining parts (2) has an opening (24) with a rotationally symmetrical opening cross section with an inner peripheral surface , which forms the second joining surface (25), the joining section (32) of the first joining part (3) being arranged with radial play (S) coaxially within the opening (24) of the second joining part (2), and between the first and second The joining gap (6) is formed on the joining surface (33 and 25), which has a radial width (B) which corresponds on average to half the radial play (S/2),

characterized,

that the adhesive (51) is filled with separate solid particles (7).

Method according to claim 1, characterized in that at least some of the solid particles (7) have a grain size at least equal to half the radial play (S/2) between the joining sections (32, 24).

Method according to one of the preceding claims, characterized in that the solid particles (7) at least partially have a greater hardness than the joining parts (3, 2) in the area of the joining surfaces (25, 33).

Method according to one of the preceding claims, characterized in that the solid particles (7) are formed as irregularly shaped grains.

5. Method according to one of the preceding claims, characterized in that the grain size is larger than half the radial play (S/2) between the joining sections (32, 24).

6. The method according to claim 5, characterized in that the grain size is between 0.1% and 50%, preferably between 1% and 10%, larger than half the radial play (S/2) between the joining sections (32, 24) .

7. The method according to claim 1, characterized in that the joining surfaces (25, 33) are designed in the shape of a cylinder jacket.

8. Method for producing a cohesive joint connection between two joining parts (2, 3) in steering systems, characterized by the steps:

- applying an adhesive (51) to at least one of the joining surfaces (25, 33), which is filled with separate solid particles (7),

and

- Coaxial positioning of the joining parts (3, 2) relative to one another outside the joining gap (6),

afterward:

- moving the joining parts (3, 2) relative to one another with joining surfaces (25, 33) lying opposite one another in the joining gap (86) in at least one direction of extension of the joining surfaces (25, 33),

- Positioning the two joining parts (3, 2) in a desired joining position.

9. The method according to claim 8, characterized in that the joining surfaces (25, 33) lying opposite in the joining gap (6) are moved in the axial direction relative to one another.

10. The method according to claim 8, characterized in that the joining surfaces (25, 33) lying opposite in the joining gap (6) are moved relative to one another in the circumferential direction.

1 1. Steering shaft with a connection arrangement comprising two joining parts (2, 3), one joining part (2) being a joint fork (21) and the other joining part (3) being a shaft, with a between the two joining parts (2, 3). Joining gap (6) is arranged, characterized in that an adhesive (51) is introduced into the joining gap as a connecting agent and separate solid particles (7) are arranged in the joining gap (6).