Rolling bearing with multi-component plastic bearing ring

Abstract

The invention relates to a rolling bearing, in particular a ball bearing, comprising an inner ring and an outer ring in the form of two bearing rings mounted so as to be rotatable relative to one another about an axis, each constituting a guide part of a guide provided between the bearing rings, the guide part surrounding the axis, the guide part constituted by the inner ring being radially opposed to the guide part constituted by the outer ring, in which rolling elements, in particular balls, are distributed around the axis and abut against the two guide parts such that the rolling elements roll on the two guide parts when the bearing rings rotate relative to one another about the axis, at least one of the bearing rings comprises a sliding ring constituting the guide part of the bearing ring and a stabilizing ring abutting the sliding ring so as to surround the axis, the sliding ring being made from a first plastic material and the stabilizing ring being made from a second plastic material, the first plastic material being softer than the second plastic material, in particular the rolling elements being mounted without lubricant in the guides.

Description

[Technical field]

[0001] The present invention relates to a rolling bearing according to the preamble of claim 1 and to a device comprising said rolling bearing and an outer part and an inner part, the two parts being mounted so as to be rotatable relative to each other and connected to each other by the rolling bearing. [Background technology]

[0002] A typical rolling bearing is known in the prior art. The rolling bearing has two bearing rings, in particular an inner ring and an outer ring. The inner ring is at least partially surrounded by the outer ring and at least partially radially spaced from the outer ring, and rolling elements are provided between the inner ring and the outer ring and are arranged to roll on both bearing rings while being in contact with the two bearing rings. As a result, the bearing rings are mounted rotatably relative to one another around the axis of the rolling bearing, which can absorb not small radial forces due to the provision of the rolling elements. In a broad embodiment, the rolling bearing is configured as a ball bearing in which balls are provided as rolling elements. The present invention relates in particular to such a ball bearing. Furthermore, in a preferred embodiment, the rolling bearing is configured as a deep groove ball bearing, in which the inner ring and the outer ring together form a groove-like guide for the balls, which are guided between the bearing rings, so that they can also absorb certain axial forces. The present invention relates in particular to such a deep groove ball bearing. It should be noted that in general, the suitability of a rolling bearing to absorb forces is based on the forces acting relatively between the inner and outer rings of the rolling bearing. It should also be noted that in general, the term "axial" refers to a direction along the axis of the rolling bearing about which the bearing rings are mounted so as to be rotatable relative to one another, and the term "radial" refers to a direction perpendicular to this axis.

[0003] Thus, in a typical rolling bearing, each of the bearing rings has a guide section of a guide, which is formed between the bearing rings, in which the rolling elements are mounted between the bearing rings. The guide sections of the bearing rings are thus radially opposite one another, and the rolling elements are radially arranged between the guide sections. Each of the guide sections is configured to surround the shaft in a closed manner. The balls are distributed in the guide around the shaft, in particular evenly distributed, and are arranged in contact with both guide sections in the guide, such that the rolling elements roll on both guide sections when the bearing rings rotate relative to one another around the shaft. In principle, such a rolling bearing can reliably ensure a low-friction bearing arrangement of two bearing rings rotatable around an axis, where the bearing rings are reliably positioned relative to one another both in the axial and radial directions. However, this rolling bearing has various disadvantages. For example, conventional rolling bearings require a great deal of lubrication of the rolling elements in the guides to enable long-term reliable functioning. If the interference fit of the rolling bearing between the bearing rings is too strong, friction will be too great, which will lead to wear and heating at high speeds. If the interference fit is too weak, there is a risk of play between the bearing rings. Furthermore, the choice of material for the manufacture of this rolling bearing is difficult. On the one hand, sufficient stability of the bearing rings must be ensured, and on the other hand, the lowest possible friction between the rolling elements and the bearing rings should be realized, and furthermore, the rolling bearing should ideally be suitable for both low and high rotational speeds of the bearing rings relative to one another around the axis. Since this rolling bearing is used on a large scale to support a wide range of components relative to one another, the bearing rings and the rolling bearings as a whole should also be as cost-effective as possible. Summary of the Invention

[0004] It is an object of the present invention to provide a rolling bearing or a device equipped with a rolling bearing which at least partially remedies at least one disadvantage or problem occurring with typical rolling bearings or devices.

[0005] As a solution to the problem underlying the invention, the invention proposes a rolling bearing having the features according to claim 1.

[0006] The rolling bearing comprises an inner ring and an outer ring as two bearing rings of the rolling bearing mounted so as to be rotatable relative to one another around an axis. Each of the inner ring and the outer ring forms a guide part surrounding the axis of a guide provided between the bearing rings, in particular a guide part surrounding the axis in an uninterrupted closed manner. The guide part formed by the inner ring is radially opposite the guide part formed by the outer ring. The guide part may be formed by side faces of the inner and outer rings facing each other in the radial direction. In the guide, the rolling elements are distributed around the axis and arranged in abutting manner on both guide parts. Preferably, the rolling elements are fixed both in their axial position and in their radial distance from the axis by their contact with the two guide parts. When the bearing rings rotate relative to one another around the axis, the rolling elements roll on both guide parts. By rolling the rolling elements on the guide parts, the bearing rings are mounted rotatably relative to one another by the rolling elements. Preferably, the rolling elements are evenly distributed around the axis such that an equal angular spacing around the axis is always provided between two adjacent rolling elements in the direction of rotation around the axis. The rolling bearing is preferably configured as a ball bearing and the rolling elements as balls. In other embodiments, rolling elements other than balls may be provided, for example cylindrical bodies. According to the invention, at least one of the bearing rings has a sliding ring forming a guide for the bearing ring and a stabilizing ring abutting the sliding ring so as to surround the axis. The sliding ring is manufactured from a first plastic material and the stabilizing ring is manufactured from a second plastic material. The first and second plastic materials are different from each other, the first plastic material being softer than the second plastic material. In an embodiment, the rolling bearing according to the invention may have the features disclosed without any connection to a rolling bearing in general.

[0007] The configuration of the rolling bearing according to the invention has certain advantageous effects. By making the first plastic material from which the sliding ring is manufactured softer than the second plastic material from which the stabilization ring is manufactured, the first plastic material can be specifically configured to be optimized as far as possible for low-friction and low-noise interaction with the rolling elements, without compromising the overall stability of the bearing ring. This is because the stabilization ring ensures sufficient stabilization of the bearing ring by its hardness and associated strength. The first plastic material is particularly preferably a sliding material. Sliding materials are well known as plastic materials with good sliding properties. Tribological polymers, i.e. polymer plastics that are tribologically optimized, i.e. that have good friction and / or lubrication properties, are particularly suitable as sliding materials. Such polymer plastics are also called tribopolymers. Such sliding materials are particularly suitable for processing by injection molding. The tribopolymers can be, for example, thermoplastic or thermosetting tribopolymers. Tribopolymers generally comprise one or more base polymers and additives, which may be specifically provided to optimize wear or friction reduction. For example, finely divided solid lubricants, such as molybdenum disulfide or graphite, may be provided as additives. In one embodiment, the tribopolymer further comprises additives such as fillers, in particular plastic materials, textile fibers or particles, for example for stabilization purposes. Examples of base polymers are polyethylene (PE), polypropylene (PP), polyacetal (POM), polycarbonate (PC), polyamide (PA, PA6, PA12, PA46, PA66), polyvinyl chloride (PVC), polytetrafluoroethylene (PTFE), polyketone (PK), acrylonitrile butadiene styrene (ABS), for special applications, e.g. in the food industry and / or for good resistance at high temperatures, e.g. polyetherketone (PEK), polyetheretherketone (PEEK), polysulfone (PSU), polyphenylsulfone (PPSU), polyphenylene sulfide (PPS), the base polymer may also be constituted as a compound, e.g. a mixture of at least two of the above polymers.The thermosetting tribopolymer may for example have a phenolic resin as base polymer. According to an embodiment according to the invention, the rolling bearing may in a particularly preferred embodiment be a lubricant-free rolling bearing, whereby the rolling elements are mounted in the guides without lubricant. Such lubricant-free rolling bearings are particularly low-maintenance and environmentally friendly and may further be particularly advantageous for use in critical environments such as the food industry.

[0008] The sliding ring forms a guide for the bearing ring, so that the rolling elements roll uninterruptedly on the sliding ring, and thus on the first plastic material, when the bearing rings rotate relative to one another about their axis. Advantageously selectable properties of the first plastic material can thus ensure uninterrupted low friction between the rolling elements and the bearing ring. The stabilizing ring can ensure sufficient stability of the sliding ring over its entire circumference by ensuring that the stabilizing ring abuts against the sliding ring in a circular manner about the axis, in particular in a closed circular manner without interruption. Preferably, the stabilizing ring extends over more than 50%, in particular more than 80%, of the axial extent of the sliding ring, preferably over more than the entire axial extent of the sliding ring over its entire circumference about its axis. Preferably, the sliding ring has as two radial sides a radially inner side and a radially outer side, each of which surrounds the axis in a closed manner without interruption. One of these radial flanks forms the guide and the stabilization ring abuts against the other of these radial flanks, in particular over its entire circumferential path around its axis, without interruption. In this way, the stabilization ring can be used to provide a particularly effective stabilization of the bearing ring for application in rolling bearings. It is particularly preferred if the rolling elements are in uninterrupted contact with the sliding ring over a contact surface that is at least five times that of the stabilization ring during a 360° rotation of the bearing rings relative to one another around the axis. The contact surface over which the rolling elements abut against the sliding ring is therefore at least five times that over which the rolling elements abut against the stabilization ring. Preferably, the rolling elements do not come into contact with the stabilization ring. The stabilization ring is therefore preferably at a distance from the rolling elements in all possible rotation positions of the bearing rings, in particular around the axis relative to one another.

[0009] In a generally preferred embodiment, each of the bearing rings has a sliding ring and a stabilizing ring. The advantageous properties described above with reference to the bearing rings in the various embodiments may then be given to one or both of the bearing rings. Since both bearing rings, i.e. the inner and outer rings each have a sliding ring and a stabilizing ring as described above for the various embodiments, the entire rolling bearing can be constructed to be particularly simple, low-friction and at the same time robust. The sliding ring of the inner ring particularly preferably surrounds the stabilizing ring of the inner ring. Particularly preferably, the stabilizing ring of the outer ring surrounds the sliding ring of the outer ring. The sliding rings of the inner and outer rings thus form diametrically opposed guide parts of the guide in which the rolling bearing is guided.

[0010] Generally, the first plastic material has a Shore D hardness of less than 75, in particular less than 70, in particular less than 65, in particular less than 60. Preferably, the first plastic material has a Shore D hardness in the range from 30 to 75, in particular 35 to 65, in particular 40 to 60. Generally, and particularly preferably, the second plastic material has a Shore D hardness that is at least 5, in particular at least 10, in particular at least 15, in particular at least 20 greater than the Shore D hardness of the first plastic material. Generally, the second plastic material has a Shore D hardness of at least 60, in particular at least 65, in particular at least 70, in particular at least 75. Preferably, the second plastic material has a Shore D hardness in the range from 60 to 100, in particular 65 to 100, in particular 70 to 95, in particular 70 to 90. The inventors have found that by combining a first and a second plastic material such that the second plastic material is very hard, but the first plastic material still has a high hardness, it is possible to produce a particularly robust and at the same time low-friction rolling bearing having the characteristics of the invention. Generally preferably, the coefficient of friction between the rolling elements and the first plastic material is lower than the coefficient of friction between the rolling elements and the second plastic material. Generally preferably, the first plastic material comprises a higher proportion of lubricant than the second plastic material.

[0011] In one embodiment, only the first plastic material is configured as a slidable material, while in another embodiment, both the first and second plastic materials are configured as slidable materials.

[0012] In one embodiment, the rolling elements are rotatably mounted in a bearing cage surrounding the shaft and guided at a fixed angular distance from each other. The bearing cage is arranged radially between a guide part of the inner ring and a guide part of the outer ring. By providing a bearing cage that ensures a fixed angular distance between the rolling elements when the bearing rings rotate relative to each other, the bearing properties of the rolling bearing can be particularly favorable. The bearing rings are preferably manufactured from a sliding material. The sliding material is, for example, a plastic material, which may in particular be configured as a tribopolymer, as described above. Preferably, the sliding material from which the bearing cage is made is different from the first plastic material and / or the second plastic material. It is generally preferred that each of the inner ring, the outer ring and the bearing cage is manufactured from a plastic material. As a result, the rolling bearing is provided in a cost-efficient and environmentally friendly manner. The configuration of the inner ring, the outer ring and the bearing cage manufactured from a plastic material can be particularly advantageous for the realization of the rolling bearing as a lubricant-free rolling bearing.

[0013] In some embodiments, the rolling elements are made of a material having a higher hardness than the first plastic material, in particular the second plastic material. The rolling elements are particularly preferably made of glass, metal, plastic material or ceramic. In a particularly preferred embodiment, the rolling elements are made of glass, plastic material or ceramic. This can be particularly advantageous for the realization of lubricant-free rolling bearings.

[0014] In some embodiments, the sliding ring and the stabilization ring form-fittingly abut against each other both along the axis and perpendicular to the axis, i.e. axially and radially. A form-fitting contact can ensure a particularly high stability of the bearing ring.

[0015] In one embodiment, the stabilization ring and the sliding ring each have protrusions distributed around the axis, with every recess being provided between two adjacent protrusions. It is particularly preferred if the protrusions and especially the recesses are distributed evenly around the axis. Every one of the protrusions of the stabilization ring is arranged in every one of the recesses of the sliding ring, and every one of the protrusions of the sliding ring is arranged in every one of the recesses of the stabilization ring. The coupling of the protrusions and recesses of the stabilization ring and the sliding ring can ensure a particularly dimensionally stable connection between the stabilization ring and the sliding ring, in particular a particularly good form-fit connection. The recesses can be formed, for example, by reducing the thickness of the respective ring or by providing a recess of the respective ring that extends in one direction through the respective ring. Particularly preferably, the protrusions of the sliding ring extend together over 30% or more of the axial length of the extent of the sliding ring. This means that 30% or more of the axial extent of the sliding ring is formed by its protrusions. Thus, the projections and recesses of the sliding ring preferably extend over 30% or more of the axial length of the range of the sliding ring, since the recesses are formed perpendicular to the axial distance between the projections. Preferably, the projections of the stabilization ring extend over 30% or more of the axial length of the range of the stabilization ring. This means that more than 30% of the axial range of the stabilization ring is formed by the projections. Thus, the projections and recesses formed perpendicular to the axial direction between the projections preferably extend over 30% or more of the axial length of the range of the stabilization ring. Since the projections of the stabilization ring and / or the sliding ring extend over 30% or more of the axial length of their range, a dimensionally stable connection between the stabilization ring and the sliding ring can be ensured over a very long axial range. Particularly preferably, the projections and recesses are provided outside the axial range of the rolling elements over 50% or more of the axial length of their range, in particular over 70% or more of the axial length of their range. This can minimize the influence of the connection of the projections and recesses on the bearing of the rolling elements.

[0016] In one embodiment, at least some of the projections of the stabilization ring and the sliding ring are configured as radial projections and some of the recesses of the stabilization ring and the sliding ring are configured as radial recesses, one of the radial projections of the stabilization ring being arranged in each of the radial recesses of the sliding ring and one of the radial projections of the sliding ring being arranged in each of the radial recesses of the stabilization ring. The coupling of the radial projections and recesses can be particularly effective in preventing the stabilization ring and the sliding ring from rotating relative to each other. In a particularly preferred embodiment, the radial projection of the sliding ring is wider than the radial projection of the stabilization ring, which can be particularly advantageous for the stability of the bearing ring and thus of the stabilization ring and the sliding ring.

[0017] In one embodiment, at least a portion of the radial projections each have an increasing width along their radial extent in the radial receptacle assigned to them, forming an undercut, the corresponding radial receptacle being the receptacle in which the respective radial projection is arranged. As the radial projections expand along their radial extent into the radial receptacle assigned to them, they form a radially acting undercut, whereby the radial projections cannot move radially outwardly from the radial receptacle assigned to them by the undercut. This is particularly advantageous for the stability of the bearing ring.

[0018] In one embodiment, each of the stabilization ring and the sliding ring has a first group and a second group of protrusions, the two groups of protrusions being provided at opposite axial ends of the stabilization ring or the sliding ring. The rolling elements are preferably arranged axially between the two groups of protrusions. The rolling elements preferably extend over 50% or more, in particular over 70% of their axial extent outside the axial region in which the protrusions are arranged. The protrusions of the first group are particularly preferably configured as axial protrusions and the protrusions of the second group as radial protrusions. Particularly preferably, the protrusions of the first group are arranged within the same angular range around the axis as the corresponding protrusions of the second group. By providing two groups of protrusions, the connection between the stabilization ring and the sliding ring can be particularly favorable. As each of the two groups of protrusions is arranged within the same angular range, the ability of the stabilization ring and the sliding ring to fit together as well as their stability can be particularly favorable.

[0019] In one embodiment, the sliding ring has a greater radial extent, averaged over its circumferential path around the axis, than the stabilizing ring. This is based on the radial extent, i.e. the radial thickness, averaged over the entire circumferential path around the axis and averaged over the same axial portion. This portion comprises more than 50% of the axial length of the extent of the stabilizing ring and the sliding ring, in particular 100% of the axial length of the extent of at least one of the stabilizing ring and the sliding ring. Preferably, the radial extent, i.e. the radial thickness, is both averaged over the entire circumferential path around the axis and over the entire axial length of the extent of the stabilizing ring and the sliding ring. The inventors have realized that, although providing a sufficiently radially thick sliding ring is particularly advantageous for reliable and low-friction bearings or guiding of rolling elements, in many applications a stabilizing ring with a small thickness is already sufficient for moderate stability, since the stabilizing ring is manufactured from a plastic material with high hardness.

[0020] In one embodiment, the guide parts engage behind the rolling elements on both their axial sides. Thus, the guide parts preferably form grooves in which the rolling elements are guided. This has proven to be particularly advantageous when balls are used as rolling elements. By engaging behind the rolling elements on their two axial sides, the bearing ring and the rolling elements can be guided relative to each other by the rolling elements. It is particularly preferred when each of the guide parts has a circular part-shaped cross section that surrounds the axis, whereby said circular part-shaped cross sections that surround the axis form a surface on which the rolling elements can roll. This is particularly advantageous when balls are provided as rolling elements. It is particularly preferred when the bearing rings are fixed in their axial position relative to each other by engaging behind the rolling elements on both axial sides of the two guide parts.

[0021] In one embodiment, at least one of the guide parts adjoins the insert at one of its axial ends with an insertion bevel. Particularly preferably, both guide parts adjoin the insert at one of their axial ends with an insert having an insertion bevel, whereby the insertion bevels of the inserts surrounded by the respective bearing rings forming the respective guide parts are radially opposite each other. Providing an insert with such an insertion bevel is particularly advantageous for the joining of the bearing ring and the rolling elements. Particularly preferably, the bearing ring with the guide part has an outer diameter which increases along the axis over the path of the insert or an inner diameter which decreases along the axis over the path of the insert. Preferably, the outer ring forms the guide part adjoining the insert with the insertion bevel at one of its axial ends, the outer ring having an inner diameter which decreases along the path of the insert along the axis. The inner diameter decreases from the axial end of the outer ring towards the guide part. Particularly preferably, the inner ring forms the guide part adjoining the insert with the insertion bevel at one of its axial ends, the inner ring having an outer diameter which increases along the axis over the path of the insert, the outer diameter increasing from the axial end of the inner ring towards the guide part. While in the intended operating condition of the rolling bearing the rolling elements contact the guide parts but not the insert parts, the rolling elements can be guided along the insert parts to the guide parts when the rolling bearing comprising the inner ring, the outer ring and the rolling elements is assembled. Each of the guide parts and the insert parts is preferably formed by a sliding ring of the respective bearing ring.

[0022] In one embodiment, the sliding ring and the stabilizing ring are arranged pressed against each other by a radial interference fit. In one embodiment, the sliding ring and the stabilizing ring, in particular the bearing ring as a whole, are manufactured by injection molding. In a particularly preferred embodiment, the sliding ring and the stabilizing ring are manufactured using a multi-part injection molding process, or one of the sliding ring and the stabilizing ring is injection molded relative to the other of the sliding ring and the stabilizing ring. The sliding ring and the stabilizing ring can be manufactured simultaneously if manufactured using a multi-part injection molding process. Different plastic materials are used for each of the two rings. When manufactured by injection molding the sliding ring relative to the stabilizing ring or the stabilizing ring relative to the sliding ring, one of the sliding ring and the stabilizing ring is manufactured first and then the other is manufactured by injection molding relative to the one.

[0023] In one embodiment, at least one of the bearing rings, in particular at least the inner ring, has a flange that extends radially along the rolling elements and covers them on one of their axial sides. The rolling elements can be protected by such a flange, whereby the ingress of particles that result in friction or other damage can at least be reduced. The flange is particularly preferably formed by a stabilizing ring. Particularly preferably, the flange is in sliding contact with a sliding ring of the other bearing ring around the axis. Since both bearing rings each have a sliding ring and a stabilizing ring, and the stabilizing ring that forms the flange abuts against the sliding ring of the other bearing ring, on the one hand, the best possible sealing and thus the best possible protection of the rolling elements or the guide with the rolling elements arranged thereon is made possible by the contact of the flange with the sliding ring, and on the other hand, as a result, the friction between the bearing rings is kept as low as possible. The recesses distributed around the axis are particularly preferably in the flange, with the flange being formed by the stabilizing ring and the sliding ring extending partly into the recess, or the flange being formed by the sliding ring and the stabilizing ring extending into the recess. It is particularly advantageous to ensure a dimensionally stable connection between the stabilization ring and the sliding ring by having the other ring extend into the recess of the flange. Preferably, each ring (the stabilization ring or the sliding ring without the flange) extends into the recess by its projection as described above.

[0024] In one embodiment, the inner ring has an overhanging projection on its radially inner surface and / or the outer ring has an overhanging projection on its radially outer surface for rotationally fixed engagement in a first component rotatably mounted relative to the second component by means of a rolling bearing. The first component is rotatably fixed to the inner or outer ring, the overhanging projection of the inner or outer ring being located in a receptacle provided on the first component. The second component is rotatably fixed to the other inner or outer ring. Thus, the two components are rotatably mounted relative to each other by means of rolling bearings, and each of the inner and outer rings is rotatably fixed to one of the two components. Preferably, one of the components is surrounded by the inner ring and thereby pressed with a radial interference fit, and the other component is circumferentially pressed with a radial interference fit against the outer periphery of the outer ring.

[0025] In one embodiment, the inner ring has a receptacle on its radially inner surface for receiving the shaft, the receptacle having a diameter of 8 mm or more, in particular 1 cm or more, in particular 5 cm or more. Preferably, the outer ring has an outer diameter of less than 4 cm, in particular less than 3 cm, in particular 1 cm or more larger than the diameter of the receptacle of the inner ring.

[0026] The invention further relates to a device comprising an outer component, in particular a frame part or gear part, an inner component, in particular a shaft or other gear part, and a rolling bearing according to the invention. The inner ring is connected to the inner component, in particular by an interference fit, and the outer ring is connected to the outer component for conjoint rotation. The components are rotatably connected to each other by a rolling bearing and are mounted such that they can rotate relative to each other around the axis of the rolling bearing with as low friction as possible due to the properties of the rolling bearing according to the invention. The device is particularly preferably a bicycle. In one embodiment, the outer component is a bicycle frame, in particular a wheel fork of the bicycle frame, and the inner component is a wheel axle or a bottom bracket axle. In one embodiment, the outer component is a gear part of a bicycle transmission of the bicycle and the inner component is another gear part of the bicycle transmission. For example, the bicycle transmission is a bottom bracket transmission, and two gear parts of the bottom bracket transmission are mounted such that they can rotate relative to each other by means of rolling bearings. For example, a bottom bracket transmission may have a number of gears, in particular a sun gear, a ring gear and at least one planetary gear and a web shaft with at least one rotation axis for the planetary gears, at least one of the gear parts, i.e. for example the sun gear, the ring gear, the at least one planetary gear and / or the web shaft, is rotatably mounted to another one of the gear parts by means of a rolling bearing. [Brief description of the drawings]

[0027] [Figure 1] 1A to 1C are various schematic basic views of an embodiment of a rolling bearing according to the present invention. [Diagram 2] 1 shows various schematic basic views of the outer ring of the rolling bearing according to FIG. [Diagram 3] 1 shows various schematic basic views of the inner ring of the rolling bearing according to FIG. [Figure 4] 1A to 1C show various schematic basic views of further embodiments of a rolling bearing according to the present invention. [Diagram 5] FIG. 4 shows various schematic basic views of the outer ring of the rolling bearing according to the present invention. [Figure 6] FIG. 4 shows various schematic basic views of the inner ring of the rolling bearing according to the present invention. [Figure 7] FIG. 2 shows a schematic basic view of a bearing cage of an embodiment of a rolling bearing according to the invention. [Figure 8] 1A to 1C show various schematic basic views of further embodiments of a rolling bearing according to the present invention. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0028] The invention is explained in more detail below with reference to eight drawings based on an exemplary embodiment.

[0029] In FIG. 1, which consists of FIGS. 1A, 1B and 1C, an embodiment of a rolling bearing 1 according to the invention is shown diagrammatically in various schematic views. FIG. 1A shows a plan view along the axial direction of the rolling bearing 1. FIG. 1B shows a cross-sectional view according to the section AA. FIG. 1C shows a perspective view. The rolling bearing 1 according to the embodiment shown in FIG. 1 has as two bearing rings an inner ring 3 and an outer ring 2. The inner ring 3 is arranged radially inside the outer ring 2. Each of the two bearing rings forms a guide part which together form a guide for the rolling elements 4, which in this case are configured as balls. The guide parts of the inner ring 3 and the outer ring 2 face each other in the radial direction and therefore face each other in the radial direction, as can be seen in particular from FIG. 1B. The rolling elements 4 are held in contact with the guide parts between the inner ring 3 and the outer ring 2. Furthermore, the rolling bearing 1 has a bearing cage 5 arranged radially between the inner ring 3 and the outer ring 2, partially surrounding the balls, i.e. the rolling elements 4, and ensuring that the rolling elements 4, i.e. the balls, are positioned at a uniform angular distance from each other.

[0030] In FIG. 2, consisting of FIGS. 2A, 2B, 2C and 2D, different views of the outer ring 2 or components of the outer ring 2 are shown in different schematic views. The outer ring 2 comprises a sliding ring 22 and a stabilizing ring 21. The sliding ring 22 is manufactured from a sliding material, in this case from a tribopolymer. The sliding ring 22 preferably forms more than 50%, in particular more than 70%, in particular the majority, preferably the entire radially inner surface of the outer ring 2, which is generally advantageous according to the invention. The sliding ring 22 forms the guide parts 20 of the outer ring 2, which engage behind the rolling elements 4 on their two axial sides and have a circular part-shaped cross section. This cross section is perpendicular to its circumferential path around the axis.

[0031] The guide part 20 also adjoins directly an insert part 220, where the sliding ring 22 has an insert bevel, in which the outer ring 2 has an inner diameter that decreases along the axis starting from its axial end towards the guide part 20. The guide part 20 is suitable for reliable guiding of the rolling elements 4, in this case configured as balls, and the insert part 220 is used for easy insertion of the balls into the guide part 20 during assembly of the rolling bearing 1. The sliding ring 22 and the stabilizing ring 21 also have a number of protrusions 211, 212, 222, 223. Each of the protrusions 211, 212 of the stabilizing ring 21 is received in a corresponding recess of the sliding ring 22, which recess is formed between two adjacent protrusions 222, 223 of the sliding ring 22. The term "adjacent protrusions" means adjacent along a circumferential path around the axis. In particular, when viewing Figures 2A and 2C in combination, it can be seen that the stabilizing ring 21 and the sliding ring 22 each have radial protrusions 212, 223, the radial protrusions 223 of the sliding ring 22 being wider than the radial protrusions 212 of the stabilizing ring 21, each of the radial protrusions 212, 223 forming undercuts in their assigned radial receptacles with increasing widths along their radial extent. These undercuts are clearly visible in Figure 2A. Due to these undercuts, relative radial movement of the sliding ring 22 and the stabilizing ring 21 is effectively prevented. In the described exemplary embodiment, the stabilizing ring 21 and the sliding ring 22 each have two groups of protrusions. A first group of protrusions 222, 211 is provided at a first axial end of the respective ring, and a second group of protrusions 212, 223 is provided at a second axial end of the respective ring. The guide parts 20 and the rolling elements extend with their axial extent substantially outside the axial extent of the projections. By the interaction of the projections 211, 212, 222, 223, the sliding ring and the stabilization ring are connected to each other in a form-fitting manner in the radial and axial directions. Approximately 30% of the axial length of the extent of the rings is formed by the projections 211, 212, 222, 223.

[0032] In FIG. 3, consisting of FIGS. 3A, 3B, 3C and 3D, the inner ring 3 or components of the inner ring 3 are shown in various views in a schematic diagram. The inner ring 3 comprises a stabilizing ring 32 and a sliding ring 31. The sliding ring 31 surrounds the stabilizing ring 32. The stabilizing ring 32 forms a receptacle for receiving the shaft. The stabilizing ring 32 is manufactured from a hard second plastic material and is therefore adapted to be fitted to the shaft by an interference fit. As explained above with reference to FIG. 2 for the outer ring 2, the stabilizing ring 32 and the sliding ring 31 each have mutually engaging projections 313, 321, 322, i.e. one of the projections engages in a recess formed between and assigned to the projections of the other ring, as explained in FIG. 2 with reference to the outer ring 2. The sliding ring 31 preferably forms more than 50%, in particular more than 70%, in particular at least the majority, preferably the entire radially outer surface, of the inner ring 3, which is generally advantageous according to the invention. The sliding ring 31 forms on its radially outer side a guide section 30 of the inner ring 3, which in the rolling bearing 1 is diametrically opposed to the guide section 20 of the outer ring 2 and, like the guide section 20 of the outer ring 2, has a circular part-shaped cross section in which the rolling elements 4, in this case balls, are guided and held by undercuts acting in the axial direction. The sliding ring 31 also forms an insert section 310 adjacent to the guide section 30, in which the outer diameter of the inner ring 3 increases continuously from its axial end towards the guide section 30, which is generally advantageous according to the invention. In combination, Figures 1 to 3 show that both the guide sections 20, 30 and the insert sections 220, 310 are diametrically opposed to one another, which makes the assembly of the rolling bearing 1 and the guiding of the rolling elements 4 in the assembled rolling bearing 1 particularly favorable.

[0033] In FIG. 4, consisting of FIGS. 4A, 4B and 4C, a further embodiment of a rolling bearing 1 according to the invention is shown in various schematic views. FIG. 4A shows a plan view along the axial direction. FIG. 4B shows a cross-sectional view along the section AA. FIG. 4C shows a plan view of the rolling bearing 1. The rolling bearing 1 has an inner ring 3 and an outer ring 2. Rolling elements 4 in the form of balls are arranged radially between the inner ring 3 and the outer ring 2 and are held at a certain angular distance from each other in a bearing cage 5. With reference to the equivalent parts of the rolling bearing 1 according to FIG. 4, reference is made to the description of the rolling bearing 1 according to FIGS. 1 to 3. In the following, only the differences between the rolling bearing according to FIG. 4 and the rolling bearing 1 described above will be described. FIGS. 4 to 6, each of which relates to the rolling bearing shown in FIG. 5, are generally described. In FIG. 5, consisting of FIGS. 5A, 5B, 5C and 5D, the outer ring 2 or the components of the outer ring 2 are shown in various schematic views. In FIG. 6, consisting of FIGS. 6A, 6B, 6C, 6D, 6E and 6F, the inner ring 3 or components of the inner ring 3 are shown diagrammatically in various views.

[0034] The outer ring 2 comprises a sliding ring 22 forming the guide part 20 of the outer ring 2 and a stabilizing ring 21 completely surrounding the sliding ring 22, which is generally advantageous according to the invention. The sliding ring 22 forms the entire radially inner side of the outer ring 2, and the stabilizing ring 21 forms the entire radially outer side of the outer ring 2. The stabilizing ring 21 forms a flange 215, which is arranged to protrude in the radial direction. This flange 215 is particularly advantageous as a stop when the rolling bearing 1 is attached by its outer ring 2 to an external component of the device with a tight fit. The inner ring 3 also comprises a stabilizing ring 32 and a sliding ring 31. The sliding ring 31 completely surrounds the stabilizing ring 32 and forms a major part of the radially outer side of the inner ring 3, which is generally advantageous according to the invention. It is therefore generally advantageous according to the invention if the sliding ring 22 of the outer ring 2 forms a major part of the radially inner side of the outer ring 2. The sliding ring 31 of the inner ring 3 and the sliding ring 22 of the outer ring 2 form the guide parts 30, 20 of the inner ring 3 and the outer ring 2, respectively, which adjoin an insert part 310, 220. The guide parts 20, 30 and the insert parts 220, 310 lie radially opposite one another. The stabilization ring 32 of the inner ring 3 forms a radially projecting flange 325. In particular, in the combined view of Figures 4 to 6, it can be seen that this flange 315 radially covers the rolling elements 4 on one of their axial sides. The flange 325 abuts in sliding contact against the sliding ring 22 of the outer ring 2, which ensures low friction on the one hand and a reliable protection of the rolling elements 4 on the other hand. A recess 323 is provided in the flange 325, through which the sliding ring 31 of the inner ring 3 extends. This ensures a particularly good form-fit between the sliding ring 31 and the stabilization ring 32 of the inner ring 3. Furthermore, the stabilization ring 32 has a group of projections at each of its two axial ends, every two adjacent projections forming between them a recess 321, 322. The projections 311, 312 formed by the sliding ring 31 are located in each of these recesses 321, 322. Thus, the sliding ring 22 and the stabilization ring 21 of the outer ring have connecting projections 2121, 2122, 2221.

[0035] 7 shows in a schematic diagram a bearing cage 5 of an embodiment of a rolling bearing 1 according to the invention. The bearing cage 5 which is generally advantageous according to the invention is configured as a closed ring surrounding the axis and has a number of rolling element receptacles 51, each spaced apart from one another at the same angular distance with respect to rotation about the axis. These rolling element receptacles 51 are configured to receive the rolling elements 4 in the form of balls, so as to surround the rolling elements 4 over more than half of their circumference, which is generally advantageous according to the invention. This ensures a particularly good fixation of the balls relative to one another by the bearing cage 5.

[0036] In figure 8 consisting of figures 8A, 8B, 8C and 8D, a further embodiment of a rolling bearing according to the invention or of a component of a rolling bearing according to the invention is shown in various diagrams in a schematic diagram. In the following, only the differences compared to the exemplary embodiment shown in figures 4 to 6 are described. The rolling bearing 1 according to figure 8 has an outer ring 2 and an inner ring 3 that are configured substantially similarly to the outer ring 2 and the inner ring 3 of the exemplary embodiment according to figures 4 to 6. However, the stabilizing ring 32 of the inner ring 3 has a radial overhanging projection 320 on its radially inner side. This radial overhanging projection 320 generally advantageously extends over more than 50% of the axial length of the extent of the inner ring 3, in this case over the entire axial length of said extent. Since the protruding portion 320 is formed by the stabilization ring 32 and protrudes radially inward from its inner surface, the protruding portion 320 may be particularly advantageously suited for rotationally fixed mounting of the inner ring 3 of the rolling bearing 1 to an inner component of a device having a receptacle corresponding to the protruding portion 320. [Explanation of symbols]

[0037] 1. Rolling bearings 2 Outer Ring 3 Inner Ring 4 Rolling elements 5 Bearing cage 20 Guide section 21 Stabilizing Ring 22 Sliding ring 30 Guide section 31 Sliding ring 32 Stabilizing Ring 51 Rolling element receptacle 220 Insertion part 211 Protrusion 212 Protrusion 215 Flange 222 Protrusion 223 Protrusion 310 Insertion part 311 Protrusion 312 Protrusion 313 Protrusion 320 Overhanging protrusion 321 Protrusion 322 Protrusion 323 Protrusion 325 flange 2121 Protrusion 2122 Protrusion 2222 Protrusion

Claims

1. A rolling bearing, in particular a ball bearing, a bearing ring in the form of two bearing rings mounted so as to be rotatable relative to one another about an axis, comprising an inner ring and an outer ring, each of which constitutes a guide part of a guide provided between said bearing rings, said guide part surrounding said axis, said guide part constituted by said inner ring being radially opposed to said guide part constituted by said outer ring, in which rolling elements, in particular balls, are distributed around said axis and abut against the two guide parts in such a way that said rolling elements roll on said two guide parts when the bearing rings rotate relative to one another about said axis, A rolling bearing, wherein at least one of the bearing rings has a sliding ring constituting the guide portion of the bearing ring and a stabilizing ring abutting the sliding ring so as to surround the shaft, the sliding ring being manufactured from a first plastic material and the stabilizing ring being manufactured from a second plastic material, the first plastic material being softer than the second plastic material, and in particular the rolling elements being mounted in the guide without lubricant.

2. 2. The rolling bearing according to claim 1, wherein each of the bearing rings comprises a sliding ring and a stabilizing ring, in particular the sliding ring of the inner ring surrounding the stabilizing ring of the inner ring and the stabilizing ring of the outer ring surrounding the sliding ring of the outer ring.

3. 3. A rolling bearing according to claim 1, wherein the rolling elements contact the sliding ring with a contact surface that is at least five times larger than that of the stabilisation ring, the stabilisation ring being spaced apart from the rolling elements.

4. 4. A rolling bearing according to claim 1 , wherein the first plastic material has a Shore D hardness of less than 75, in particular less than 70, in particular less than 65, and the second plastic material has a Shore D hardness of at least 5, in particular at least 10, in particular at least 15, and in particular at least 65, in particular at least 70, in particular at least 75, higher than the Shore D hardness of the first plastic material.

5. 5. A rolling bearing according to claim 1, wherein the first plastic material is a slidable material.

6. the coefficient of friction between the rolling elements and the first plastic material is lower than the coefficient of friction between the rolling elements and the second plastic material; and / or 6. A rolling bearing according to claim 1, wherein the first plastic material comprises a higher proportion of lubricant than the second plastic material.

7. 7. A rolling bearing according to claim 1, wherein the rolling elements are rotatably mounted in a bearing cage surrounding the shaft and guided at a fixed angular distance from each other, the bearing cage being arranged radially between the guide parts of the inner ring and the outer ring, and in particular made from a sliding material, in particular each of the inner ring, the outer ring and the bearing cage being made from a plastic material.

8. 8. A rolling bearing according to claim 1 , wherein the rolling elements are made from a material having a higher hardness than the first plastic material, in particular than the second plastic material, in particular the rolling elements are made from glass, metal, a plastic material or ceramic.

9. 9. A rolling bearing according to claim 1, wherein the sliding ring and the stabilisation ring abut with a form-fit against each other both along the axis and perpendicular to said axis.

10. 10. A rolling bearing according to claim 1, wherein the stabilisation ring and the sliding ring each have protrusions distributed around the axis, each recess being provided between two adjacent protrusions, each one of the protrusions of the stabilisation ring being arranged in one of the recesses of the sliding ring, each one of the protrusions of the sliding ring being arranged in one of the recesses of the stabilisation ring, in particular the protrusions of the sliding ring extending over 30% or more of the axial length of the extent of the sliding ring and the protrusions of the stabilisation ring extending over 30% or more of the axial length of the extent of the stabilisation ring.

11. 11. The rolling bearing according to claim 10, wherein at least a portion of the protrusions of the stabilization ring and the sliding ring are configured as radial protrusions and a portion of the recesses are configured as radial recesses, one of the radial protrusions of the sliding ring is arranged in each of the radial recesses of the sliding ring, and one of the radial protrusions of the sliding ring is arranged in each of the radial recesses of the stabilization ring, in particular the radial protrusions of the sliding ring are wider than the radial protrusions of the stabilization ring.

12. 12. The rolling bearing according to claim 11, wherein at least a portion of said radial projections each have an increasing width along their radial extent in their assigned radial receptacle, forming an undercut.

13. 13. A rolling bearing according to claim 10, wherein each of the stabilisation ring and the sliding ring has a first and a second group of protrusions, the two groups of protrusions being provided at opposite axial ends of the stabilisation ring or the sliding ring, the rolling elements being arranged axially between the protrusions of the two groups and / or the protrusions of the first group being configured as axial protrusions and the protrusions of the second group being configured as radial protrusions, in particular both protrusions of the first group being arranged within the same angular range around the axis as the corresponding protrusions of the second group.

14. 14. A rolling bearing according to claim 1, wherein the sliding ring has a greater radial extent averaged over a circumferential path around the axis than the stabilisation ring.

15. 15. A rolling bearing according to claim 1, wherein each of the guide parts engages behind the rolling elements with their two axial sides, in particular each of the guide parts has a circular part-shaped cross-section which surrounds the axis, in particular the bearing rings are fixed in their axial position relative to each other by the two guide parts engaging behind the rolling elements with both axial sides.

16. 16. A rolling bearing according to claim 1, wherein at least one of the guide portions adjoins an insert portion at one of its axial ends with an insertion inclined surface, and in particular the bearing ring having said guide portion has an outer diameter that increases along the axis over the path of the insert portion or an inner diameter that decreases along the axis over the path of the insert portion.

17. 17. A rolling bearing according to claim 1, wherein the sliding ring and the stabilisation ring are pressed against one another by a radial interference fit and / or are manufactured by injection moulding, in particular the sliding ring and the stabilisation ring are manufactured by multi-part injection moulding and / or one of the sliding ring and the stabilisation ring is moulded to the other of the sliding ring and the stabilisation ring.

18. 18. A rolling bearing according to claim 1, wherein at least one of the bearing rings, in particular the inner ring, has a flange extending radially along the rolling elements and covering the rolling elements on one of their axial sides, in particular the flange being formed by the stabilisation ring, in particular the flange abutting in sliding contact around the axis against the sliding ring of the other of the bearing rings.

19. 19. The rolling bearing according to claim 18, wherein the flange is provided with recesses distributed around the axis, the flange being formed by the stabilization ring and the sliding ring extending partially into the recesses, or the flange being formed by the sliding ring and the stabilization ring extending into the recesses.

20. 20. A rolling bearing as claimed in any one of claims 1 to 19, wherein the inner ring has an overhanging projection on its radially inner surface and / or the outer ring has an overhanging projection on its radially outer surface for rotationally fixed engagement into a first component which is rotatably mounted by the rolling bearing relative to a second component.

21. 21. A rolling bearing according to any one of claims 1 to 20, wherein the inner ring has a receptacle on its radially inner surface for receiving a shaft, the receptacle having a diameter of at least 1 cm, in particular at least 5 cm, and the outer ring has an outer diameter of less than 4 cm, in particular less than 3 cm, in particular at least 1 cm larger than the diameter of the receptacle of the inner ring.

22. A device comprising an outer component, in particular a frame component or a gear component, an inner component, in particular a shaft or another gear component, and a rolling bearing according to any one of claims 1 to 21, A device, wherein the inner ring is connected to the inner component, in particular by an interference fit, and the outer ring is connected to the outer component for conjoint rotation, said components being rotatably connected to each other by the rolling bearing, in particular said device being a bicycle, said outer component being a bicycle frame, in particular a wheel fork of said bicycle frame or a gear part of a bicycle transmission of said bicycle, and said inner component being a wheel axle, a bottom bracket axle or another gear part of said bicycle transmission.

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