AXIAL-RADIAL PLAIN BEARINGS

Description

[0001] The invention relates to an axial-radial plain bearing, in particular a rotary table bearing comprising a first bearing ring and a second bearing ring, wherein the bearing rings are arranged to be rotatable relative to one another about a bearing axis and the second bearing ring forms a substantially U-shaped cross section in order to accommodate the first bearing ring at least in sections, further comprising sliding elements made of a polymer material which are arranged between the first and second bearing rings in order to decouple the bearing rings axially and radially, wherein the sliding elements each have a substantially L-shaped cross section with an axial region comprising axial sliding surfaces and a radial region comprising radial sliding surfaces.

[0002] Such axial-radial plain bearings are designed to absorb both axial and radial forces and are used, for example, for rotary indexing tables, dividing heads, for the design of CNC rotary axes, and for the support of pivoting screens, etc. A tribologically suitable polymer can be used as the polymer material for the production of the sliding elements, which can generally be applied without lubricant.

[0003] A generic axial-radial plain bearing is described, for example, in utility model DE 20 2013 101 374 U1. The advantages of such conventional plain bearings include, in particular, the low friction between the bearing rings, maintenance-free operation, cost-effective production, robust construction, and high wear resistance. In addition to reliably absorbing radial and axial loads, including tilting moment loads on the bearing location despite its small size, these conventional axial-radial plain bearings significantly reduce the effort and thus the costs for designing adjacent structures and installing the bearings. The multitude of these advantages has led to the increasing popularity of such polymer rotary table bearings (PRT) in a wide variety of applications.

[0004] Further prior art is known from FR 3 035 461 A1.

[0005] In a majority of applications of such plain bearings, the task may be to repeatedly and precisely move to and fix a predetermined relative rotational position of the two bearing rings to each other when executing a rotational movement of the two bearing rings to each other, for example when used on an assembly table.

[0006] In this respect, the object of the present invention is to further develop a conventional axial-radial plain bearing in such a way that a relative rotational position of the two bearing rings of the plain bearing to each other can be approached reliably and reproducibly without this requiring a high level of additional design effort starting from a conventional axial-radial plain bearing and without this additional functionality being accompanied by the need for increased installation space for the plain bearing.

[0007] The present invention already achieves this object with an axial-radial plain bearing comprising the features of claim 1. The axial-radial plain bearing according to the invention has a first bearing ring and a second bearing ring, wherein the bearing rings are arranged so as to be rotatable relative to one another about a bearing axis, and the second bearing ring forms a substantially U-shaped cross section in order to accommodate the first bearing ring at least in sections, further comprising sliding elements made of a polymer material which can be used for tribological purposes, which are arranged between the first and second bearing rings in order to decouple the bearing rings axially and radially, i.e. to reduce the friction of the bearing rings in the axial and radial directions relative to one another, wherein the sliding elements each have a substantially L-shaped cross section with an axial region comprising axial sliding surfaces and a radial region comprising radial sliding surfaces.The axial-radial plain bearing according to the invention is characterized in that at least one of the two bearing rings has a seat for a deflectable locking element received therein, which can be subjected to force, and the other of the two bearing rings comprises at least one locking recess assigned to the locking element for at least partially receiving the deflectable locking element to provide a releasable locking at a predetermined relative rotational position of the two bearing rings to one another.

[0008] The axial-radial plain bearing according to the invention is based on the fundamental idea of ​​designing the relative arrangement of the two bearing rings to one another in such a way that at least two operating situations or operating positions of the two bearing rings to one another can be provided, namely a first in which the two bearing rings are freely rotatable relative to one another about the bearing axis and at least a second, with a predetermined relative rotational position of the first and second bearing rings to one another, in which the relative movement of the two bearing rings to one another is blocked, wherein, however, by applying a predetermined release torque or a release force, this blockage can be released or removed again. According to the invention, this blockage of movement of the two bearing rings to one another is provided by a releasable locking of the two bearing rings to one another.By providing a force-loaded locking element on one of the two bearing rings, which interacts with an associated locking recess on the other bearing ring to releasably block the relative rotation of the two bearing rings, the desired functionality can be provided without requiring special structural designs that would otherwise increase the overall volume of the bearing. The described locking of the two bearing rings to one another occurs after the at least one predetermined relative rotational position between the two bearing rings has been set, in which the locking element is moved into the at least one locking recess due to the application of force and thus engages with the associated locking recess.

[0009] The designation of surfaces of the plain bearing according to the invention or of its components as axial surfaces or radial surfaces refers to surfaces that are substantially perpendicular to the axial direction or radial direction of the bearing. L-shaped, in relation to the shape of the sliding elements, can refer to a design in which the respective sliding elements have axial and radial sliding surfaces that can be oriented approximately 90° to each other. The extent of the axial sliding surfaces in the radial direction can be greater than the extent of the radial sliding surfaces in the axial direction of the bearing. However, the term "L-shaped" sliding elements also includes embodiments in which the extent of the axial sliding surfaces in the radial direction is smaller than or equal to the extent of the radial sliding surfaces in the axial direction of the bearing.

[0010] Further developments of the invention as well as additional features of the invention are specified in the general description, the figures, the description of the figures and the dependent claims.

[0011] It can be expediently provided that the complementary locking means provided on both bearing rings are arranged on opposite surfaces of the two bearing rings, so that they are designed to releasably block the relative rotational movement of the two bearing rings to each other.

[0012] According to the invention, the locking element and locking recess, which are designed to interact and complement each other, can be arranged on mutually facing boundary surfaces of the two bearing rings. In an expedient embodiment, it can be provided that the locking element and the at least one locking recess are arranged on mutually facing radial surfaces of one and the other bearing ring. In this case, it can be provided that the locking element arranged in the seat of one bearing ring is subjected to a force in the radial direction and is arranged so as to be deflectable in order to provide a locking of the two bearing rings to one another in the radial direction when setting a predetermined relative rotational position of the two bearing rings to one another.However, it can also be provided that the locking element and the at least one locking recess are arranged on mutually facing axial surfaces of one and the other bearing ring, and that the locking element arranged in the seat of one bearing ring is subjected to force in the axial direction and deflectable. Furthermore, it is also possible for a locking element and at least one associated locking recess to be arranged on mutually facing radial surfaces of one and the other bearing ring, and at the same time for a further locking element and at least one associated locking recess to be arranged on mutually facing axial surfaces of one and the other bearing ring, so that the two bearing rings can be locked to one another both on the mutually facing axial surfaces and on the mutually facing radial surfaces.

[0013] It can expediently be provided that the seat area for receiving the force-loaded and deflectable locking element on one of the bearing rings is designed without a sliding element in order to provide the desired locking. It can be provided that in the area of ​​the locking element seat on one of the two bearing rings on the axial surface, no or no section of the L-shaped sliding elements are provided, but at least one other sliding element which extends alone in the axial surface or alone provides an axial surface, such that the radial deflection of the locking element is not impeded by this sliding element during locking. In particular, it can be provided that in the area of ​​the seat of the locking element on the radial surface of one of the two bearing rings, no sliding element or no section of a sliding element is arranged.

[0014] The design of the bearing according to the invention can be implemented in such a way that the release torque for releasing the locking of the two bearing rings to one another can be generated by applying a predetermined torque to one of the bearing rings while the other bearing ring is held stationary, this predetermined torque representing a torque threshold above which the locking can be released. For this purpose, the locking element can be designed with a corresponding curved locking surface. It can expediently be provided that the locking element has, at least in sections, a spherical or cylindrical locking surface which, in a locking position of the locking element, corresponds to the at least one associated locking recess with a complementary locking surface of this locking recess. The term locking surface therefore refers to the contact surface of the locking element or the associated locking recess.The described curved configurations of the locking surfaces or contact surfaces make it easy to achieve the desired releasability of the locking mechanism. By appropriately designing the locking surfaces of the locking element and the locking surfaces of the locking recess associated with the locking element, it is possible to set the release torque differently depending on the direction of rotation of the two bearing rings, which can be useful in certain applications.

[0015] To design the second bearing ring with a substantially U-shaped cross-section, it can be provided that it has two axially spaced ring sections that are connected by an axial flange to form a receptacle in which the first bearing ring is arranged at least in sections between these two axially spaced ring sections of the second bearing ring. Depending on the embodiment, the axial flange can be arranged radially inward or radially outward to the two axially spaced, generally coaxially aligned, ring sections. Depending on the application, embodiments are particularly expedient in which the axial flange of the second bearing ring is arranged radially inward to the two axially spaced ring sections, so that the outer radial surface of the first bearing ring, which is partially received by the second bearing ring, is exposed and can comprise a functional surface, for example a functional surface of a gear.

[0016] According to the invention, the locking element can be designed in one or more pieces. In particular, it can be designed in one piece as a pin element, for example as a cylindrical pin element. The length of the locking element, which corresponds to an associated locking recess on the other bearing ring, can be adjusted to establish a predetermined release torque at which a set locking position between the two bearing rings of the axial-radial plain bearing according to the invention can be released. In those embodiments in which the locking element can be designed as a cylindrical pin element, the associated locking recess can correspond to a partial volume of the cylindrical volume of the pin element, wherein the partial volume can have a substantially identical extent in the axial direction of the bearing as the cylindrical locking element.

[0017] It can be provided that the longitudinal extent (axial extent) of the locking element is more than half the axial dimension of the bearing ring with the smallest axial extent. In a particularly expedient embodiment, it can be provided that the axial extent of the locking element substantially corresponds to the axial extent of the radial flange of the second bearing ring, so that the locking of the two bearing rings can be provided over the entire axial extent of the radial flange. For this purpose, it can be provided that the axial extent of the associated locking recess corresponds to the axial dimension of the locking element, so that the described locking effect between the locking element and the locking recess is present over its entire extent after the setting of a predetermined relative rotational position between the two bearing rings, in which the force-loaded locking element engages with the associated locking recess.

[0018] In order to provide a force application to the locking element, for example, a clamping element, in particular in the form of a screw element, can be provided, which presses on the locking element, which is in particular elastically deformable, and generates an elastic reaction force with which the locking element plunges into the associated locking recess for locking when a predetermined relative rotational position of the two bearing rings to one another is present.

[0019] In another embodiment, a spring device, in particular in the form of a spiral spring, can be provided, which can be arranged in a bore, for example a radial bore, of one bearing ring and is clamped between the locking element and a radial stop element, such as a screw. Preferably, the longitudinal axis of the spiral spring can be oriented approximately perpendicular to a longitudinal axis of the locking element.

[0020] In order to provide a plurality of relative rotational positions of the two bearing rings to one another and thus a plurality of assembly positions, particularly in the design of an assembly table, it can be expediently provided that the other of the two bearing rings has a plurality of circumferentially spaced-apart locking recesses for successively receiving the locking element upon rotation of the two bearing rings to one another.

[0021] In order to ensure the most wear-free operation of the axial-radial plain bearing according to the invention, it can be expediently provided that the seat for the locking element on one of the two bearing rings is designed to essentially completely accommodate the locking element in relative operating positions or operating positions of the two bearing rings to one another outside of a locking position. Furthermore, this structural design can provide the most play-free arrangement of the two bearing rings relative to one another.

[0022] In principle, the seat of the locking element can be arranged on the second bearing ring or the first bearing ring, and the associated at least one locking recess can be arranged correspondingly on the second bearing ring or the first bearing ring. In embodiments in which the axial flange of the second bearing ring is provided radially inward for connecting the two axially spaced ring sections, the at least one locking recess can expediently be arranged on the second bearing ring, in particular on the axial flange of the second bearing ring, and the seat of the locking element can be arranged on the first bearing ring. This embodiment has the particular advantage that the element for applying force to the locking element is accessible from the radial outside, which can facilitate any maintenance of the bearing.

[0023] In the design of the plain bearing according to the invention, it can be provided that, in order to release the locking of the two bearing rings to one another, they are not separated by applying a predetermined torque to one of the bearing rings, but rather by providing and actuating a corresponding actuating device with which the locking element can be brought out of engagement with the at least one locking recess. The actuating device can be arranged on one of the two bearing rings, wherein it can have an actuating section that is movable relative to this bearing ring and is operatively connected to the locking element. In particular, it can be provided that the actuating section is arranged so that its movement is coupled to the locking element, wherein this movement coupling can be realized in the form of a coupling with respect to a linear movement of the actuating section and the locking element in a ratio of 1:1, but does not have to be.Instead, a reduction or transmission of the movement, possibly also with a change of direction between the actuating section and the locking element, can be provided and designed in the movement coupling.

[0024] It can expediently be provided that the locking mechanism, by bringing the locking element into engagement with the at least one associated locking recess, provides such a positive connection between the first and second bearing rings that this cannot be released without destruction without actuating the actuating device, even when a high torque is applied to one of the bearing rings. It can expediently be provided that the locking element, in the locked state, engages in the at least one associated locking recess over a predetermined radial extent and that mutually associated locking surfaces on the locking element and the locking recess are designed such that when a torque acts on one of the bearing rings, no or only a small force component can be generated on the locking element, which presses the locking element out of the locking recess against the applied force.For example, in one embodiment, it can be provided that the at least one locking recess is formed by flat surfaces, while the locking element has flat boundary surfaces in the region of engagement with the locking recess. In one embodiment, it can also be provided that the locking element is cylindrical, wherein the cylinder axis can be oriented, in particular, radially to the one of the bearing rings on which the seat of the locking element is arranged.

[0025] Also in the embodiment of the axial-radial plain bearing according to the invention, which has a described actuating device, it can be provided for the design of the second bearing ring with a substantially U-shaped cross section that said second bearing ring has two axially spaced ring sections which are connected by an axial flange, for the design of a receptacle in which the first bearing ring is arranged at least in sections between these two axially spaced ring sections of the second bearing ring.It can expediently be provided that the axial flange of the second bearing ring is arranged radially inward of the two axially spaced ring sections, so that the outer radial surface of the first bearing ring, which is partially received by the second bearing ring, is exposed and can have a functional surface on which in particular the actuating device can be arranged, which facilitates the accessibility of the actuating section of the actuating device.

[0026] In general, the term "actuating section" of the actuating device refers to a section on which a user engages manually or a controllable actuator of the actuating device, in particular to release the locking of the locking element and the associated locking recess, wherein the actuating section can be arranged to be radially deflectable relative to one of the two bearing rings for this purpose.

[0027] In a particularly expedient embodiment, it can be provided that a force transmission element, for example a tension and / or compression means such as a Bowden cable or a rod-shaped element, is arranged between the operatively connected, in particular movement-coupled, locking element and actuating section. For example, by using such a force transmission element, the actuating device can be actuated remotely from the axial-radial plain bearing according to the invention. In a particularly simple embodiment, it can also be provided that the locking element and actuating section are manufactured integrally, in particular formed in one piece, with a force transmission element such as a rod section possibly located therebetween.

[0028] For example, the integral component can be designed as a rod-shaped element that provides an actuating section at one end and the locking element at the other. In this application, the term "element" is to be understood broadly and can also refer to a section of a component. Furthermore, several such elements or sections can be integrally formed as a single component.

[0029] To apply force to the locking element, in the embodiment of an axial-radial plain bearing according to the invention that includes such an actuating device, the locking element can be arranged in a spring-loaded manner such that the locking element engages into the at least one locking recess after a predetermined rotational position of the two bearing rings relative to one another has been set. In particular, the actuating device can have a spring device, e.g. in the form of a spiral spring, which acts directly or indirectly on the locking element and is supported on a section fixed to one of the bearing rings, so that the locking element engages into an associated locking recess for locking when a predetermined relative rotational position of the two bearing rings relative to one another is present.Due to the operative connection between the actuating section and the locking element, this spring-elastic preload of the locking element can also be realized by a corresponding spring device acting on the actuating section and / or on the intermediate force transmission element.

[0030] Also in the design of an embodiment of an axial-radial plain bearing according to the invention, which has an actuating device for actuating the locking element, it can expediently be provided that, in order to provide an assembly table, a plurality of relative rotational positions of the two bearing rings to one another and thus a plurality of assembly positions are provided in that the other of the two bearing rings has a plurality of circumferentially spaced-apart locking recesses for successively receiving the locking element upon rotation of the two bearing rings to one another.

[0031] In order to prevent the locking element from rubbing against a radial surface of the other bearing ring after the release of the locking of the two bearing rings and the subsequent relative rotation of the bearing rings to one another, in particular to set a further assembly position, after the removal of an actuating force on the actuating section against the force applied to the locking element, it can expediently be provided that the actuating device is set up and designed to lock in an operating position in which the locking of the locking element in the at least one locking recess is released, i.e. the engagement of the locking element in the at least one associated locking recess is canceled by retracting the locking element from the locking recess. This locking can, for example, be effected by force-locking, e.g.by clamping the locking element, the actuating section operatively connected to the locking element, and / or a force transmission element or section arranged between them. In another embodiment, it can also be provided that the actuating device is designed and constructed for positive locking in an operating position. For example, it can be provided that the actuating section, the locking element, and / or a force transmission element or section arranged between them.-section, starting from a locking position of the locking element for releasing the locking, is arranged to be movable in a positively guided manner over a predetermined distance threshold in the radial direction relative to one of the two bearing rings and, after exceeding the distance threshold, is arranged to be rotatable about a radial direction for setting a radial positive connection between the actuating section, the locking element and / or a force transmission element or section arranged between them and the other of the two bearing rings.

[0032] In a particularly expedient embodiment, the actuating device can be provided with a controllable actuator, which is designed to provide an actuating force or an actuating torque, in particular in such a way that manual actuation can be omitted, which facilitates handling of the plain bearing according to the invention. Such an actuator can be an electric, pneumatic, or hydraulic actuator, whereby such an actuator is also referred to in the field as an adjustment unit.

[0033] It should be noted that in embodiments in which the actuating device of the sliding bearing has a controllable adjustment unit, the locking element accommodated in the seat does not necessarily have to be arranged in a force-loaded manner, particularly in embodiments in which the adjustment unit is self-locking. Such a sliding bearing can be designed like one of the sliding bearings described above, with the exception of the fact that the locking element is not subjected to force in a locked operating position and / or in an unlocked operating position, i.e., is arranged force-free, whereby this operating position can be held or fixed by the adjustment unit.

[0034] The adjustment unit can be designed to linearly extend or retract a thrust tube, in particular as an electric cylinder, pneumatic cylinder, or hydraulic cylinder. Preferably, such an adjustment unit can be motion-coupled on the output side to the actuating section of the actuating device, in particular connected to it for linear movement of the actuating section, or the actuating section can be an integral component of the adjustment unit. The use of an electric cylinder, which can in particular comprise a linear drive with a motor and a spindle driven by the motor, can be constructed compactly and allows simple integration into the inventive arrangement of the first and second bearing rings to design an inventive axial-radial plain bearing.

[0035] It can expediently be provided that the actuator or the adjustment unit is designed to set at least two operating positions of the bearing rings relative to one another, namely a locked operating position in which the two bearing rings are locked relative to one another in that the locking element engages in a locking recess assigned to the locking element, and a released operating position in which the two bearing rings are arranged unlocked relative to one another in that the locking element does not engage in any assigned locking recess. Such an actuator or such an adjustment unit can be designed to be controllable, for example in that the user causes a control signal, in particular an electrical control signal, to the actuator or the adjustment unit and thus causes the actuator or the adjustment unit to change its operating position, in particular to lock or release the locking of the two bearing rings relative to one another.

[0036] In a particularly expedient embodiment, the axial-radial plain bearing according to the invention can also be prepared to connect a user-selected actuator to the actuating device of the axial-radial plain bearing according to the invention. For this purpose, it can be provided, for example, that the actuating section of the actuating device has a mechanical coupling device such as a bolt thread or a nut thread for coupling to an actuating unit, which can be configured on the output side with a complementarily designed coupling device, i.e., here, a nut thread or a bolt thread, and can be coupled to the coupling device of the actuating device.

[0037] Adjusting or releasing the locking of the two bearing rings to each other or of the locking element in an associated locking recess can lead to wear on the associated locking surfaces during operation of the plain bearing, which makes maintenance or replacement of specified components necessary after a specified operating period. For this purpose, the axial-radial plain bearing according to the invention can have a monitoring device for detecting the locking and / or non-locking states of the axial-radial plain bearing. This monitoring device can be integrated, in particular, into the actuating device, the actuator, or the adjustment unit.The monitoring device can, for example, comprise an electrical contact, which can be coupled in particular to the actuating section for movement and can, for example, be configured and arranged such that the triggering of the contact indicates a secure locking of the two elements to one another. For example, the electrical contact can have a fixed section and a section coupled in movement to the actuating section, wherein the two sections of the contact are arranged to be movable toward one another by the movement of the actuating section until an electrical contact is established.

[0038] In one embodiment, the monitoring device can also be provided with a counting device for determining the number of locking / non-locking states set during operation, for example, to derive a wear indicator. Furthermore, the monitoring device can be provided with a memory device for storing the determined number of locking / non-locking states, which can be read out, for example, by an external control device to estimate a wear state and / or to determine a maintenance interval.

[0039] The sliding elements can expediently be designed as an injection-molded part, wherein a material thinning in the manner of a film hinge can be provided between the radial and axial sliding surfaces for bending the radial to the axial sliding surfaces by approximately 90°, so that with a single sliding element both a radial and an axial sliding surface of the axial-radial plain bearing according to the invention are provided.

[0040] In order to facilitate the assembly of the plain bearing according to the invention in particular, it can be expediently provided that an individual sliding element comprises, in the region of its axial sliding surface, a plurality of first sectors which are arranged essentially without gaps in the installed position, i.e. in the assembled state of the bearing, and which are circumferentially successive, wherein these sectors can be trapezoidal in shape, for example. Furthermore, it can be provided that the sliding element comprises, in the region of its radial sliding surface, a plurality of sectors which are arranged circumferentially spaced from one another and which are circumferentially successive, such that the respective sliding element can be arranged in a circle such that the first sectors are arranged between opposite axial boundary surfaces of the first and second bearing rings and the second sectors are arranged between the opposite radial boundary surfaces of the first and second bearing rings.Particularly expediently, it can be provided that at least two such sliding elements are included and arranged such that, with respect to their axial sliding surface, they are axially offset from one another by approximately the axial dimension of the first bearing ring and circumferentially offset from one another by approximately half the circumferential dimension of the first sectors. This makes it possible to ensure that radial boundaries between the first sectors and radial boundaries between the second sectors of the sliding elements do not overlap one another circumferentially, but are offset from one another, which can increase the load-bearing capacity of the axial-radial plain bearing according to the invention.

[0041] The invention will be explained below by describing an embodiment together with modifications with reference to the accompanying drawings, in which Figure 1 in a perspective view of an axial-radial plain bearing designed according to the invention, Figure 2 inFigure 1 shown inventive plain bearing in a longitudinal section Figure 3 the inventive bearing of the Figure 1 in a plan view with a partial removal of the second bearing ring, Figure 4 the second bearing ring of the plain bearing according to the invention of the Figure 1 in a perspective individual view, Figure 5 the first bearing ring of the plain bearing according to the invention of Figure 1 in a perspective individual view, Figure 6 a partial view of the sliding elements of the sliding bearing according to the invention of Figure 1 in a perspective view, Figure 7 in a perspective view of an axial-radial plain bearing designed according to the invention of a second embodiment, Figure 8 in Figure 7shown axial-radial plain bearing in a sectional view to show an actuating element, Figure 9 shows components of the actuating element in an exploded view, Figure 10 shows a perspective exploded view of an axial-radial plain bearing designed according to the invention of a third embodiment, Figure 11 shows a perspective exploded view of an axial-radial plain bearing designed according to the invention of a fourth embodiment, and Figure 12 shows a perspective exploded view of an axial-radial plain bearing designed according to the invention of a fifth embodiment.

[0042] In Figure 1An axial-radial plain bearing 1 according to the invention is shown in a perspective view. The bearing 1 has a first or inner bearing ring 2, which is arranged coaxially to a second or outer bearing ring 4 and is received by the latter over its entire axial extent and over a portion of its radial extent. For this purpose, the second bearing ring 4 is approximately U-shaped in a section that encompasses the longitudinal axis of the plain bearing. Both bearing rings 2, 4 can be made of the same or different metal materials such as aluminum or steel. However, it is also possible to form at least one of the bearing rings or both from a plastic material, in particular at least in sections.

[0043] In the illustrated embodiment, the first bearing ring 2 is formed in one piece, in the manner of a hollow cylinder with a low overall height, while the second bearing ring 4 is composed of two ring sections 41 a, b that are axially spaced and connected by means of an axial flange 42 to form the described ring with a U-shaped cross-section. Between the mutually facing radial and axial surfaces of the two bearing rings 2, 4, L-shaped sliding elements 6 are provided to decouple or eliminate the friction between the bearing rings on the mutually facing axial and radial surfaces. The dimensions of the axial height of the first bearing ring, including the thickness of the sliding elements 6, are adapted to the axial spacing of the ring sections 41 a, b of the second bearing ring or its receptacle, such that the two bearing rings 2, 4 are arranged to rotate relative to one another about the axis A of the plain bearing with essentially no play or with a small gap.Depending on the application, the axial-radial plain bearing according to the invention can be used in such a way that the first bearing ring or the second bearing ring is arranged in a stationary manner, while the other bearing ring is rotatable relative to the first-mentioned one.

[0044] Figure 2 shows the axial-radial plain bearing of the Figure 1in a sectional view, wherein the sectional plane encompasses the bearing axis A. As can be seen, in the described embodiment, the second bearing ring 4 is formed by an L-shaped ring 43, which provides a ring section 41b and an axial flange 42, to the free end of which a ring 44 is fastened, so that the radial surface 45 and the two axial surfaces 40a, b of the L-shaped ring 43 and of the ring 44, respectively, form a receptacle for the first bearing ring 2. As can be seen, the axial surfaces 20a, b of the first bearing ring face the axial surfaces 40a, b of the second bearing ring; correspondingly, the radial surface 45 of the second bearing ring and the radial surface 21b of the first bearing ring face each other, with sliding elements 6 being arranged therebetween with corresponding sector sections parallel to the specified axial and radial surfaces of the two bearing rings, in order to enable the two bearing rings to rotate relative to each other with as little friction as possible.

[0045] Figure 3 shows the axial-radial plain bearing 1 designed according to the invention in a frontal view, wherein the ring 44, which is screwed to the L-shaped ring 43 to form the second bearing ring 4, has been removed. In this respect, Figure 3A frontal view of the axial surface 20a of the first bearing ring 2, on which a plurality of sliding element sectors 60 are arranged in the axial overlap region of the first bearing ring 2 with the second bearing ring 4 to provide axial sliding surfaces. To adjust the respective curvature, the sliding element sectors 60 extending circumferentially and in the radial direction are trapezoidal in shape, so that a slot 61 is located between adjacent sectors. The sliding element sectors 60 completely cover the radially inner section of the axial surface 20a except for an angular section in which a seat 7 for a locking element 8 is arranged in the first bearing ring 2. In the described embodiment, the locking of the two mutually rotatable bearing rings takes place on the respectively facing radial surfaces of the two bearing rings 2, 4.The locking element is designed here as a cylindrical pin that is spring-loaded and arranged in an approximately rectangular recess adapted to the diameter of the locking element. This recess thus acts as a seat 7 for the locking element 8, with the relative position of the locking element within the seat depending on the respective relative rotational state of the two bearing rings 2, 4. As shown, the seat has a substantially cuboid shape or recess, wherein the base section, i.e., the radial limiting section, can be curved, in particular adapted to the curvature of the locking element 8.

[0046] In the described embodiment, the locking element 8 is subjected to force in the radial direction by means of a spring element 80, here in the form of a spiral spring, wherein the spring element is located on a fastening element, for example a radially arranged screw 81, see Figure 1, supports. The Figure 3 The specified relative rotational position of the two bearing rings 2, 4 results in the two bearing rings being locked to one another, since in the specified relative rotational position, the locking element 8 is pressed into a locking recess 9 assigned to it due to the application of force, so that the free rotation of the bearing rings relative to one another is blocked. As can be seen, the radial surface 45 of the axial flange 42 has four locking recesses 9 spaced circumferentially by 90° and adapted to the cylindrical shape of the locking element 8, so that the four locking positions defined as described can be approached in a defined manner during a full rotation.

[0047] As shown, in the area of ​​the seat 7 for the locking element 8 on the axial surface 20a, no sliding element sector of one of the described sliding elements is provided to provide a corresponding axial sliding surface section in trapezoidal shape, but instead two additional, here rod-shaped, sliding elements 5, each of which extends with its end face out of its associated, axially extending bore in the first bearing ring and flush with the sliding element sectors 60 of the sliding elements 6.

[0048] Figure 4shows the second bearing ring in a perspective oblique view of the radial surface 45 and one of the locking recesses 9, which in the described embodiment extends over the entire axial spacing between the two ring sections 41a, b and is thus adapted to the axial length of the locking element 8. The four locking positions provided in the described embodiment of the axial-radial plain bearing according to the invention correspond to four relative rotational positions of the two bearing rings 2, 4 to one another and can be resolved by applying a torque above a predetermined threshold, the resolution here being set symmetrically, ie independently of the direction of rotation, due to a symmetrical design of the locking surfaces of the locking element and the associated locking recess(es).

[0049] Figure 5shows an oblique view of the first bearing ring 2 of the axial-radial plain bearing 1 according to the invention in a single view. Visible is the radially inner radial surface 21b facing the radial surface 45 of the second bearing ring, on which the seat 7 is formed in the form of a recess adapted to the locking element 8. A radial bore 22, starting from the outer radial surface 21a, pierces the seat approximately axially centrally and, in the assembled state, accommodates the spring element 80 and the support screw 81. According to the illustration of the Figure 4 the seat extends axially over the entire thickness of the first bearing ring 2.

[0050] Figure 6shows, in a detail and in an individual view, sliding elements 6 for designing the axial-radial plain bearing 1 according to the invention. In the described embodiment, two rows of identically constructed sliding elements 6 are used, with a single sliding element providing an axial sliding element sector 60 and a radial sliding element sector 64. In the described embodiment, the axial sliding element sectors are trapezoidal, with both sectors 60, 64 being arranged at an angle of approximately 90° to one another to form an approximately L-shaped sliding element. For this purpose, each sliding element 6 has a film hinge 65, which can be formed by thinning the material in this area.In this embodiment, a first row of sliding elements 6 is arranged circumferentially one after the other in the region of the radial inner section of the first bearing ring 2, so that the axial surface 20a can be occupied by the axial sliding element sectors 60 and the inner radial surface 21b can be occupied by the radial sliding element sectors 64 of the sliding elements 60, see . Fig. 5 In addition to this first row of sliding elements, the Figure 5 A further row of sliding elements 6 with sliding element sectors 60 is arranged on the lower axial surface 20b of the first bearing ring 2, wherein the corresponding radial sliding element sectors 64 in turn bear against the inner radial surface 21b of the first bearing ring 2 for the axial and radial decoupling of the bearing rings 2, 4 in the assembled state of all components of the axial-radial plain bearing.

[0051] As from Figure 6As can be seen, the arrangement can be such that the radial sliding element sectors 64 of the two rows of sliding elements abut one another at their ends, so that twice the dimension of the sliding element sectors 64 in the radial direction essentially corresponds to the thickness of the first bearing ring 2. As can be seen, the sliding element sectors 64 of the sliding elements are designed such that by offsetting both rows of sliding elements by half the circumferential extent of a sliding element in the region of the film hinge 65, the sliding element sectors 64 engage with one another, so that the inner radial surface 21 of the inner bearing ring 2 is essentially completely covered by the sliding element sectors 64, and so that in this embodiment the axial thickness of the first bearing ring 2 essentially corresponds to the axial extent of a sliding element sector 64 in the axial direction in the installed position.

[0052] In a further embodiment not shown, it can be provided that all sliding elements of the two Figure 6 specified circumferential rows of sliding elements are connected to one another, in particular in the area of ​​the film hinges 65. Such a link chain of sliding elements can also be produced in a simple manner, for example, by an injection molding process.

[0053] The person skilled in the art will recognize that other geometric designs of the sliding element sectors 60, 64 are also possible depending on the respective application or the operating forces occurring.

[0054] With reference to the Figures 7 to 9 A second embodiment of an axial-radial plain bearing 1' according to the invention is described below, wherein Figure 7the sliding bearing 1' in a perspective view, which in terms of the design and relative arrangement of the first and second bearing ring and the sliding elements arranged therebetween and in terms of further details such as the basic design and arrangement of the locking element and the at least one locking recess associated therewith is identical to that shown with reference to the Figures 1 - 6 described embodiment. Therefore, the following will only discuss different configurations of the second embodiments described with reference to the figures.

[0055] The plain bearing 1` of the Figure 7 has an actuating element 91 as part of an actuating device 90, which in the described embodiment comprises an actuating section 92, which is in operative connection with a locking element or locking section 8', here is motion-coupled, see Figure 8, which the axial-radial plain bearing 1` according to the invention of Figure 7 in a sectional view perpendicular to the axis, with a view of the cut-out actuating element 92. Also visible in the sectional view are the locking recesses 9' arranged on the axial flange 42' of the second bearing ring 4', which in this embodiment are identical to the locking recesses 9 of the Figures 1 to 6 described embodiment. These extend here over the entire axial extent of the axial flange 42'. In an embodiment not shown, these locking recesses 9' can also be cylindrical and therefore do not extend over the entire axial extent of the axial flange 42', so that in this embodiment the recesses can be designed to be axially closed. As in Figure 8As shown, the actuating element 91 can have, in addition to the actuating section 92, a locking element 8' arranged integrally therewith, which in this embodiment can be designed as a pin-like cylinder, the circumferential extent of which is adapted to the circumferential extent of the associated locking recesses 9' in order to avoid circumferential play between the first and second bearing rings (2', 4') after the locking has been set. As can be seen, the seat 7' associated with the locking element 8' is essentially designed as a radial passage in the first bearing ring 2', in which a fastening sleeve 95 of the actuating element 91 is arranged, see Figure 9, which is an exploded view of the actuating device 90. In addition to the fastening sleeve 95, the actuating device 90 has an actuating element 91, which is elongated here and has the locking element 8' at a first end and an actuating section 92 at the opposite end, wherein both end sections of the actuating element are rigidly connected to one another by a connecting section 93.

[0056] In the assembled state, the actuating element 91 extends through the fastening sleeve 95 and is supported thereon via a spring (not shown) in such a way that the actuating element 91 and thus its locking element or locking section 8' is subjected to radially inward force towards the two bearing rings, so that in a predetermined rotational position of the two bearing rings relative to one another, in which the locking element 8' of the actuating element 91 lies radially opposite one of the locking recesses 9', the actuating element 91 with its locking element or locking element section 8' comes into engagement with the respective locking recess 9'.

[0057] A locking release, ie, disengaging the locking section of the actuating element 91 from a respective locking recess 9', is carried out by pulling the actuating section 92 radially outwards. In order to avoid that the actuating element 91 has to be permanently pulled outwards when setting a further assembly position or a further relative position of the two bearing rings to each other, the actuating device 90 has a functionality for locking an operating position in which lockings are present between the locking element and one of the locking recesses. For this purpose, in the described embodiment, the fastening sleeve 95 has a guide slot 96 running radially towards the bearing rings, which guide slot 96 is provided with a Figure 9concealed radial projection in the region of the actuating section 92 cooperates for the radial forced guidance of the actuating element 91 to the fastening sleeve 95. In such an operating position, in which the actuating element 91 or the projection guided through the guide slot 96 comes out of engagement with the guide slot 96, the actuating element 91 is arranged for rotation relative to the fixed fastening sleeve 95, so that the guide pin arranged on the actuating element 91 comes into radial positive engagement with the end wall 97 of the fastening sleeve 95, so that the actuating device 90 is locked.This locking can be released by turning the actuating element back to the starting position, in which the radial form fit is released and the guide pin again engages with the guide slot 97, so that the actuating element is pressed radially inwards due to the spring force loading on the locking element 8' and thus on the actuating element as long as no force counteracting the spring force is introduced into the system via the actuating section 92.

[0058] The following figures 10 to 13 show different axial-radial plain bearings 1', which in terms of the design and arrangement of the first bearing ring 2', the second bearing ring 4' and the sliding elements 6 as well as the seat 7' do not differ from the embodiment of the Figures 7 , 8 but only with regard to the design of the actuating device 100, 110, 120, which will be discussed below.

[0059] In the embodiment of the Figure 10The actuating device 100 comprises a rod-shaped housing 101, which is designed as a threaded sleeve 102 at its end facing the locking element 8', via which the actuating device 100 can be screwed into the threaded bore 22' of the first bearing ring 2'. In this embodiment, the locking element 8' is connected via a pulling means designed as a Bowden cable 105 to an actuating section (not shown in the figure), in particular a manually actuated section. For example, an actuating section of the actuating device, such as an actuating lever, can be provided that is arranged remotely from the actual plain bearing comprising the two bearing rings, via which a tensile force can be applied to the Bowden cable 105 in order to release a detent position between the first and second bearing rings 2', 4'.For this purpose, the Bowden cable 105 is arranged in a movement-coupled manner with the locking element 8', for example, attached to it directly or with the interposition of at least one further component.

[0060] In the Figure 11In the illustrated embodiment of an axial-radial plain bearing designed according to the invention, the actuating device 110 has on its housing a threaded sleeve 102 facing the locking element 8', with which the device 110 can be screwed into the associated threaded bore 22' of the first bearing ring 2'. The locking element 8' is in turn arranged to be movable in the radial direction relative to the housing of the actuating device 110 and, in the described embodiment, is rigidly connected to a coupling bolt 112 which protrudes from the end face of the housing of the actuating device 110 facing away from the locking element. In this respect, the coupling bolt 112 in the described embodiment is arranged to be movable in the radial direction with the locking element 8' in the installed position relative to the housing of the actuating device 110 or to the first bearing ring.This embodiment of an axial-radial plain bearing designed according to the invention is particularly suitable for connection to a user-specific adjustment unit which is in the . Figure 11 is not shown and can be coupled to the coupling threaded bolt 112 by simply screwing it on, in that the adjusting unit has a complementary coupling part in the form of a nut thread.

[0061] In the embodiment of the Figure 12The actuating device 120 has an electrically actuated adjusting unit 122, which comprises an electrical monitoring contact as a monitoring device, in which a contact surface on the output side is motion-coupled to the adjusting unit to indicate a respective latching state and / or a latching release state of the plain bearing. In the described embodiment, the adjusting unit is designed as an electric cylinder, wherein the electric cylinder has a housing, relative to which the latching element 8' is displaceably arranged and which comprises a threaded sleeve 102, with which the actuating device 120 or the adjusting unit 122 can be screwed into the associated threaded bore 22' of the first bearing ring. In the described embodiment, the adjusting unit 122 is equipped with an integrated energy source, such as a rechargeable battery, so that the adjusting unit does not require an external energy source.To control the adjustment unit and / or to transmit a detected operating state via the described monitoring contact, the actuating device 120 has, in addition to the adjustment unit 122, a transceiver module 124 that is galvanically and mechanically coupled to the adjustment unit and, in particular, communicates wirelessly with an external control device. For example, control signals for controlling the adjustment unit can be transmitted to the adjustment unit via the transceiver module 124, and / or detected operating states of the locking / unlocking between the two bearing rings 2', 4' or a number of detected operating state changes can be transmitted to an external control device. List of reference symbols

[0062] 1, 1'Axial-radial plain bearing 2, 2'First bearing ring 4, 4'Second bearing ring 5Sliding element 6Sliding element 7, 7'Seat 8, 8`Locking element 9, 9`Locking recess 20a, bAxial surface 21aOuter radial surface 21bInner radial surface 22, 22`Bore 40a, bAxial surface 41a, bRing section 42, 42'Axial flange 43L-shaped ring 44, 44`Ring 45Radial surface 46Fastening screw 60Sliding element sector of the axial surface, first sector 61Slot 64Sliding element sector of the radial surface; Second sector 65Film hinge 80Spring element, spring 81Support screw 90Actuating device 91Actuating element 92Actuating section 93Connecting section, power transmission section 95Fastening sleeve 96Guide slot 97End wall 100, 110, 120Actuating device 101Housing 102Threaded sleeve 105Bowden cable 112Coupling bolt 122Actuating unit with integrated monitoring contact 124Transceiver module ARotary axis

Claims

1. Axial-radial sliding bearing (1) comprising - a first bearing ring (2) and - a second bearing ring (4), wherein the bearing rings are arranged to be rotatable against each other about a bearing axis (A) and wherein the second bearing ring (4) forms a substantially U-shaped cross section in order to receive the first bearing ring (2) at least in sections, - sliding elements (6) made of a polymer material, which are disposed between the first and the second bearing ring to decouple the bearing rings axially and radially from each other, wherein the sliding elements (6) each have a substantially L-shaped cross section with an axial region comprising axial sliding surfaces and with a radial region comprising radial sliding surfaces, characterized in that at least one of the two bearing rings has a seat (7) for a force-loaded and deflectable detent element (8) received therein and the other one of the two bearing rings (2, 4) has at least one detent recess (9) for accommodating the deflectable detent element (8) at least in sections in order to provide a releasable locking action at a specified relative rotational position of the two bearing rings (2, 4) to each other, wherein i) the axial-radial sliding bearing (1) is configured in such a way that a release torque for releasing the locking of the two bearing rings (2, 4) to each other can be generated by applying a predetermined torque to one of the two bearing rings (2, 4) while the other one of the two bearing rings (2, 4) is kept stationary, this predetermined torque representing a torque threshold from which the locking is releasable, and / or ii) the first bearing ring (2) is received by the second bearing ring (4) over its entire axial extent and over a section of its radial extent, the detent element (8) and the detent recess (9) being arranged on mutually facing boundary surfaces of the two bearing rings (2, 4).

2. Axial-radial sliding bearing (1) according to claim 1, characterized in that the detent element (8) and the detent recess (9) assigned to it are arranged on respective mutually facing radial surfaces (21b, 45) of one bearing ring and the other and that the detent element (8) arranged within the seat (7) of the one bearing ring is force-loaded and deflectable in the radial direction.

3. Axial-radial sliding bearing (1) according to claim 1 or 2, characterized in that the detent element (8) has a ball or cylinder-shaped locking surface at least in sections, which locking surface, in a locking position of the detent element (8), corresponds to the at least one detent recess (9) with a complementary locking surface of the detent recess configured in a complementary manner at least in sections.

4. Axial-radial sliding bearing (1) according to claim 1, 2 or 3, characterized in that the second bearing ring (4) has two axially spaced ring sections (41a, b) that are connected by an axial flange (42), the first bearing ring (2) being arranged between the two axially spaced ring sections (41a, b) of the second bearing ring (4) at least in sections.

5. Axial-radial sliding bearing (1) according to any one of claims 1 to 4 , characterized in that the detent element (8) is of single or multi-piece configuration and extends over more than half of the axial dimension of the bearing ring with the smaller axial extent.

6. Axial-radial sliding bearing (1) according to any one of claims 1 to 5, characterized in that a spring (80) is provided for force application to the detent element (8), which spring is arranged within a bore (22), in particular a radial bore, of one of the two bearing rings and is clamped between the detent element (8) and a radial stop element such as a screw (81).

7. Axial-radial sliding bearing (1) according to any one of claims 1 to 6, characterized in that the other one of the two bearing rings has a plurality of circumferentially spaced detent recesses (9) for successively receiving the detent element (8) upon rotation of the two bearing rings (2, 4) to each other.

8. Axial-radial sliding bearing (1) according to any one of claims 1 to 7, characterized in that the seat (7) for the detent element (8) is formed on one of the two bearing rings, for substantially completely receiving the detent element (8) in relative operating positions of the two bearing rings (2, 4) to each other outside of a locking position.

9. Axial-radial sliding bearing (1) according to any one of claims 1 to 8, characterized in that the at least one detent recess (9) is disposed on the second bearing ring (4) and the seat (7) of the detent element is disposed on the first bearing ring (2).

10. Axial-radial sliding bearing (1') according to any one of claims 1, 2, 4, 7, 8 and 9, as far as comprising feature ii), characterized in that an actuating device (90) is arranged on the one of the two bearing rings, the actuating device having an actuating section (92) movable to this bearing ring (2'), which actuating section is in operative connection to the detent element (8').

11. Axial-radial sliding bearing (1') according to claim 10, characterized in that the actuating device (90) is designed and configured to apply, via the actuating section (92), a force to the detent element, which force acts against the force application to the detent element (8') in order to release the locking of the detent element (8') and the at least one detent recess (9').

12. Axial-radial sliding bearing (1') according to claim 10 or 11, characterized in that the actuating section (92) of the actuating device is arranged to be radially deflectable relative to the one of the two bearing rings.

13. Axial-radial sliding bearing (1') according to any one of claims 10, 11 or 12, characterized in that the detent element (8') and the actuating section (92) are in operative connection via a force transmitting element or section of the actuating device (90).

14. Axial-radial sliding bearing (1') according to any one of claims 10 to 13, characterized in that the actuating device (90) is designed and configured for locking an operating position in which a locking of the detent element (8') in the at least one detent recess (9') is released.

15. Axial-radial sliding bearing (1') according to claim 14, characterized in that the actuating section (92), for releasing the locking from a locking position of the detent element (8'), is arranged to be forcibly movable in a radial direction relative to one of the two bearing rings (2', 4') over a predetermined distance threshold and, after exceeding the distance threshold, is arranged to be rotatable about a radial direction for setting a radial form closure between the actuating section (92) and the one of the two bearing rings (2').

16. Axial-radial sliding bearing (1) according to any one of claims 1 to 15, characterized in that a material thinning in the manner of a film hinge (65) is provided between the radial and axial sliding surfaces of the respective sliding elements (6) for angling the radial to the axial sliding surfaces of a sliding element (6) by approx. 90°.

17. Axial-radial sliding bearing (1) according to any one of claims 1 to 16, characterized in that a sliding element (6) comprises, in the region of its axial sliding surfaces, a plurality of first sectors (60) arranged essentially without gaps and succeeding each other circumferentially, while the sliding element (6) comprises, in the region of its radial sliding surfaces, a plurality of circumferentially mutually spaced second sectors (64) succeeding each other circumferentially.

18. Axial-radial sliding bearing (1) according to any one of claims 1 to 17, characterized in that there are comprised at least two sliding elements (6) which, in the installed position, are offset axially with respect to their axial sliding surface by approximately the axial dimension of the first bearing ring (2) and, in particular, are arranged offset circumferentially with respect to one another by approximately half the circumferential dimension of the first sectors (60).

19. Axial-radial sliding bearing (1) according to any one of claims 10 to 18, characterized in that the actuating device comprises a controllable actuator for non-manually setting and / or releasing the locking of the detent element in the at least one detent recess.

20. Axial-radial sliding bearing (1) according to any one of claims 10 to 19, characterized in that the actuating section includes a mechanical coupling device such as a bolt thread or female thread for coupling to an adjusting element.

21. Axial-radial sliding bearing (1) according to any one of claims 1 to 20, characterized by a monitoring device for the detection of locked and / or non-locked states of the axial-radial sliding bearing (1).