Method for producing a plain bearing component and plain bearing component

Abstract

A method for producing a plain bearing component (1), in particular a plain bearing bolt, is disclosed, the method comprising the steps of: providing a carrier component (2) consisting of a base material, in particular steel, metal powder injection molding or ceramic powder injection molding of a sliding layer (4) on the base material of the carrier component (2) or metal powder injection molding or ceramic powder injection molding of sliding layer segments (8-1, 8-2, 8-3) and subsequently attaching the sliding layer segments (8-1, 8-2, 8-3) to the carrier component (2).

Description

Technical area

[0001] The present invention relates to a method for producing a plain bearing component according to the preamble of patent claim 1. Furthermore, the present invention relates to a plain bearing component according to the preamble of patent claim 9. Technical background

[0002] Plain bearings are becoming increasingly important and can, for example, replace rolling bearings in planetary gears of planetary gearboxes, such as those used in wind turbines. Plain bearings have the advantage that they can support the same torques and forces as rolling bearings despite their smaller dimensions, making it possible to have either a smaller gearbox of the same performance class or a gearbox of the same size with a higher performance class. For planetary gears, a typical solution is to coat the axle bolt, on which the gear (planetary gear) is guided, with a plain bearing material. The bore of the gear is therefore directly the counter surface of the plain bearing. To date, such coated bolts, such as those used in plain bearings for gears, have preferably been manufactured by spraying a sliding layer onto, for example, a steel bolt. For this purpose, appropriate materials, e.g.Bronze metals or copper-aluminum alloys, applied either by laser cladding or cold spraying. The sliding layers, e.g., made of bronze or Babbitt, but preferably of copper-aluminum, are usually applied directly to the pin on which the gear then rotates. However, these processes are complex and costly.

[0003] The bolts can be very large and heavy parts, which represent a high cost factor even without a coating. The surfaces are usually first roughened by blasting, with areas not to be coated being manually masked. The coating is then applied using thermal spraying. Due to the slowly moving local application point, this can require a long processing time until the entire plain bearing surface has received a continuous layer and the desired thickness. The sprayed-on layer must then be mechanically machined to achieve a sliding layer with the correct dimensions and tolerances. Wear during operation may require the bearing to be replaced. In this case, the entire bolt is affected and usually requires remanufacturing, often together with the planetary gear.

[0004] It is therefore an object of the present invention to provide a simple and cost-effective production and repair of a plain bearing component. Summary of the invention

[0005] This object is achieved by a method for producing a plain bearing component according to patent claim 1 and a plain bearing component according to patent claim 9.

[0006] The plain bearing component to be manufactured can be any component in a plain bearing that is to have a sliding layer. In particular, the component can be a support pin or a support sleeve that is to be provided with a sliding layer. Furthermore, the component can generally be a component serving as the inner or outer ring of a plain bearing. In the following, the (final) component provided with a sliding layer is referred to as the plain bearing component or plain bearing pin, while the original component to which the sliding layer is applied is referred to as the support component or support pin.

[0007] Especially for smaller plain bearing components or plain bearing bolts, it can be useful to provide their supporting components directly with a firmly adhering sliding layer and thus produce one-piece plain bearing components or bolts as a material composite.

[0008] In order to simply provide such a support component with a sliding layer, the method comprises the step of providing the support component, which consists of a base material, in particular steel. As already explained, the support component that is to become the plain bearing component can be, for example, a support bolt.

[0009] The next step is to metal-powder injection mold a sliding layer onto the base material of the support component. In this case, the sliding layer is formed directly on the base material. In the case of a support pin, the metal injection molding is carried out directly around the support pin. As explained further below, the support component can have a geometry that enables a positive connection between the support component and the injection molding material, for example, through grooves. The support component is preferably preheated to prevent the injection material from cooling too quickly during overmolding.

[0010] As an alternative to metal injection molding (MIM), the sliding layer can also be formed using ceramic injection molding (CIM). For the sake of simplicity, the manufacturing process and the plain bearing component itself are described below primarily with reference to metal injection molding. However, it should be noted that all described embodiments and features apply to both types of injection molding, i.e., they are applicable to both metal injection molding and ceramic injection molding.

[0011] Especially for larger support components or support bolts, it may be useful not to provide them directly with a firmly adhering sliding layer, but to produce separate sliding layer segments and mount them on the support component.

[0012] Alternatively, sliding layer segments, especially two or more segments, can be metal powder injection molded or ceramic powder injection molded. In this variant, the process then involves attaching the sliding layer segments to the carrier component.

[0013] Metal injection molding (MIM) is similar to polymer injection molding, but uses a metal powder with a binder, most of which is later extracted during thermal curing. In particular, the metal powder can be a bronze or a copper-aluminum material suitable as a sliding layer. Spherical grains are predominantly used for metal powders to promote flow and avoid unnecessarily thick sliding layers.

[0014] In metal powder injection molding, a fine metal powder is mixed with an organic binder and then molded into shape on an injection molding machine. The injection molding machine can be configured to either spray the metal powder directly around the base material or, instead of spraying the metal powder directly onto or around the base material, to spray the metal powder as individual sliding layer segments, which can then be bonded to the base material. In both cases, a metallic sliding layer is obtained that combines the mechanical advantages of sintered components with the wide range of shaping options available with injection molding.

[0015] In particular, the metal powder injection molding process used has the advantage that particularly high quantities can be produced cost-effectively and quickly using a single injection mold. Unlike the comparatively slow direct coating of plain bearing pins using laser cladding or cold spray, the MIM process allows for very high quantities of metallic sliding coatings to be produced in a very short time.

[0016] The step of metal powder injection molding of the sliding layer or sliding layer segments involves preparing a hollow mold and filling the hollow mold with a metal powder-binder mixture. As already mentioned above, a metal powder is mixed with a binder and then filled into the hollow mold using an injection mold under pressure and temperature. The hollow mold can be arranged either around the plain bearing component to be coated, i.e., around the base material, and the space between the hollow mold and the plain bearing component is then filled with the metal powder-binder mixture. In the case of the production of sliding layer segments, however, the hollow mold only forms one segment at a time, and this hollow mold of the segment is filled separately, away from the base material. Only after the final step of removing the injected part from the reusable hollow mold and after post-processing steps such as debinding, sintering, etc.the resulting segments are attached to the base material, as explained in more detail below.

[0017] According to one embodiment, after preparing and filling the hollow mold, the process comprises the step of removing the binder and subsequent sintering. In addition to the metal powder components (or ceramic powder components), the powder (feedstock) can contain a primary binder, a residual binder, and a wetting additive. The binders can be driven off by solvent or catalytically, but usually purely thermally. The main function of the binders is to impart inherent stability to the molded parts until they acquire their metallic or ceramic properties through a final thermal sintering process.

[0018] As already mentioned, metal powder injection molding involves mixing a fine metal powder with a mostly organic binder to form the feedstock, which is then processed in an injection molding process. The metal powder-binder mixture is injected into the hollow mold using an injection molding machine. The hollow mold corresponds to the negative mold of the part to be formed, i.e., either the sliding layer including the base material, where the hollow mold encloses the base material, or the sliding layer segments.

[0019] After filling the mold and demolding, the metal powder-binder mixture is treated to remove the binder. This treatment can be carried out chemically (e.g., with solvents) or, preferably, thermally (e.g., by decomposition or evaporation).

[0020] The portion of metal powder remaining after debinding is sintered to create a dense, mechanically resilient structure. Post-processing is eliminated, as metal powder injection molding already creates a shape of the plain bearing component with the desired contours. Metal powder injection molding has the advantage that even complex geometries can be reproduced very precisely and, for most applications, do not require significant post-processing.

[0021] The steps, features and advantages described above apply analogously to ceramic powder spraying.

[0022] According to a further embodiment, the method comprises forming lubrication pockets and / or bores in the sliding layer or the sliding layer segments using elements provided in the hollow mold. The use of a hollow mold makes it possible to achieve any desired surface structure of the sliding layer or the sliding layer segments. For this purpose, the hollow mold has corresponding projections, which are reflected as depressions in the sliding layer and / or the sliding layer segments. Post-processing is not required here; rather, such depressions, which can serve as lubrication pockets, lubrication bores, or lubrication channels, can be easily formed by appropriately designing the hollow mold during injection molding. In this case, the injection mold can also consist of more than two parts and additionally have removable rods or inserts that lead to a bore in the injection-molded workpiece.Such inserts are used, for example, when the molded part cannot be demolded in any other way, i.e. it can only be removed from the tool if, for example, a separate rod that has formed a hole is removed beforehand.

[0023] The method may further comprise forming one or more elements, e.g., depressions and / or projections, on the side of a sliding layer segment facing the support component by means of the hollow mold, wherein the one or more elements can be positively connected to complementary elements of the support component. Such as lubrication pockets or the like, depressions and / or projections can also be formed in the sliding layer segments, which can then engage in complementary depressions and / or projections of the support component. In this way, the coupling between the sliding layer segments and the support component can be improved. In particular, the sliding layer segments can thereby be secured to the support component against displacement and / or rotation.

[0024] Furthermore, the method can comprise forming one or more elements on a sliding layer segment using the hollow mold, wherein the one or more elements can be connected in a form-fitting manner to complementary elements of another sliding layer segment. The sliding layer segments can thus not only be secured accordingly to the support component, but can also be connected, either additionally or alternatively, to other sliding layer segments. These elements, which can be connected to elements of other sliding layer segments, serve, for example, to insert or clamp two sliding layer segments into one another (e.g., like a puzzle piece).

[0025] Accordingly, the method may further comprise attaching at least two sliding layer segments to the support component, wherein the at least two sliding layer segments are positively connected to one another by their complementary elements. Preferably, three or more sliding layer segments are attached to the support component.

[0026] The step of metal powder injection molding or ceramic powder injection molding of sliding layer segments can, in one embodiment, comprise spraying a carrier and then overmolding it with the metal powder-binder mixture or the ceramic powder-binder mixture. This has the advantage that a cheaper material can be used as the carrier, and the more expensive sliding layer material only needs to be applied to this carrier material in a comparatively thin layer. Furthermore, a corresponding thickness is necessary to form a stable element that can be attached to the carrier component. If a sliding layer segment is made entirely from the sliding layer material, this therefore entails high costs. However, this stability can also be provided by a carrier material, such as steel, onto which the softer sliding layer material, such as bronze, is then applied only thinly.By combining injection molding of a carrier and subsequent injection molding of the sliding layer, both the advantages of metal powder or ceramic powder injection molding are achieved and a stable and cost-effective element is provided.

[0027] It should be noted that in this case, a combination of metal powder injection molding and ceramic powder injection molding can also be used. For example, the carrier can be injection-molded from metal powder and the sliding layer can then be applied to this metal carrier using ceramic powder injection molding, or vice versa. Of course, the carrier and the sliding layer can also be made of both metal or both of ceramic.

[0028] According to a further aspect, a plain bearing component, in particular a plain bearing bolt, is proposed, wherein the plain bearing component consists of a support component made of a base material, in particular steel. A sliding layer produced by metal powder injection molding or ceramic powder injection molding is provided on the base material of the support component. Alternatively, at least two sliding layer segments produced by metal powder injection molding or ceramic powder injection molding can be provided around the support component.

[0029] Since the sliding layer or sliding layer segments are manufactured by metal powder injection molding or ceramic powder injection molding, a plain bearing component is provided that can be manufactured, particularly in high volumes, at very high speeds and at minimal cost. In particular, the sliding layer or sliding layer segments can be manufactured using the method described above.

[0030] As already described above, the sliding layer or sliding layer segments can be injection molded in any shape, even with complex geometries, close to the final shape or even in the final shape. This also reduces manufacturing costs, as post-processing can be eliminated or at least reduced.

[0031] For example, the support component can be a support bolt or pin that is overmolded. The base material of the support component can, in particular, be steel. The sliding layer or sliding layer segments are arranged directly on this support component. The sliding layer or sliding layer segments can, for example, comprise copper, aluminum, and / or a copper alloy (e.g., Cu10Al, Cu-Sn (1-50%), Cu-Ni (1-99%)). Tin can also be used as an additive. A nickel content can, for example, serve to increase hardness and wear resistance.

[0032] As explained above, the sliding layer and / or the sliding layer segments can have depressions and / or recesses that serve as lubrication pockets, lubrication holes, or lubrication channels. A small guide tube can be pressed into the surface of the sliding layer segments to ensure that oil or lubricant is distributed over the surface of the segments and does not flow underneath them. Gaps between the segments can be used as lubrication channels, eliminating the need to machine such channels.

[0033] According to a further embodiment, the sliding layer segments have one or more elements on their inner circumferential surface, and the support component has one or more complementary elements on its outer circumferential surface, wherein the elements of the sliding layer segments and the complementary elements of the support component are designed to interact. In particular, the elements of the sliding layer segments and the support component can interlock to securely fasten the sliding layer segments, which are manufactured separately from the support component, to the support component (e.g., with respect to twisting and displacement).

[0034] According to a further embodiment, two sliding layer segments comprise mutually complementary elements designed to cooperate to secure the sliding layer segments to the support component. Two or more, for example, three, sliding layer segments can be arranged around the support component. To secure them to one another, the sliding layer segments can comprise corresponding, mutually complementary elements. These can interlock in the form of puzzle pieces or dovetail joints and secure the sliding layer segments to one another and thus around the support component.

[0035] As explained above, the carrier component can, for example, be a steel bolt that is inserted into an injection molding machine and clamped in place. This can be done at both ends, since these remain uncoated anyway. A defined central area can then be filled with the coating material, i.e. the metal or ceramic powder, in a single shot. As described above, the bolt can have elements that can be designed as radial recesses for axial fixation of the layer and as axial recesses for radial fixation of the layer. By overmolding the bolt, every geometry that the bolt has on its outer surface is filled with the coating material. By choosing the tool geometry or the hollow mold, it is possible to obtain oil distribution recesses (e.g. the lubrication pockets or channels described above) in the layer without any post-processing.Only an oil supply hole may need to be reworked and a sealing tube inserted.

[0036] Alternatively, several sliding layer segments (made of pure coating material or with an underlying carrier) are produced on the machine, which can then be snapped onto the bolt. In the simplest design, there can be just two halves, such as the plain bearing halves in engine connecting rods or camshaft housings. In a preferred design, more and smaller segments are provided. As in the variant described above, in which the sliding layer is sprayed directly around the bolt, the sliding layer segments can also have corresponding geometries and recesses in order to be interlocked with the bolt and / or with each other. In this case, it is also possible to reduce the thickness of the sliding layer in the area between two segments so that the segment corners are not subjected to bearing loads.The manufacturing of such sliding layer segments has the advantage that they are formed with high speed and efficiency and manually snapped onto bolts or shafts to produce the final plain bearing component.

[0037] In an exemplary embodiment, segments can be injection molded, each enveloping a steel bolt by approximately 120 degrees. In this case, three segments are required, which are mounted on a steel bolt. To manufacture each segment, a carrier is first metal powder or ceramic powder sprayed from an inexpensive but stable metallic material (hereinafter also referred to as MIM-injected or CIM-injected). This carrier is placed in a second injection mold of a second MIM or CIM injection molding machine and overmolded on its outer side with a sliding layer, which forms a form-fitting connection with the carrier via corresponding grooves. Each segment contains an oil channel bore, which ends in a shallow recess in the outer sliding layer. The steel bolt is manufactured with a central axial oil supply bore and three radial branch bores every 120°.In addition, the steel bolt is manufactured with grooves into which the backs of the supports can engage. The three segments, each consisting of a support and a sliding layer on top, are mounted on the steel bolt. In addition to engaging, snapping, or clamping the bulges on the back of the support into the steel bolt grooves, additional screws can be used. For this purpose, the steel bolt can have several threaded holes (blind holes) and the segments corresponding holes with countersunk recesses, which can also be created during the MIM injection molding process. The positions of the three segments are selected so that their oil channel holes form a continuation of the radial oil holes of the steel bolt. The result, by mounting three segments on a carrier steel bolt, is a ready-to-use plain bearing bolt, whereby the segments and their sliding layers are removable and replaceable.By feeding oil into the axial oil supply bore of the steel bolt, the oil is guided to the three segments via the three radial branch bores and through the oil channel bores of the segments to the recesses on the outer sides of the segments, which, similar to a hydrostatic bearing, store an oil volume from which oil is continuously guided between the planetary gear and the plain bearing bolt.

[0038] As already mentioned, sliding layer segments offer the further advantage that in the event of wear and / or repair, the plain bearing component does not have to be scrapped or reworked as a whole, but the sliding layer segments can simply be replaced. This can also be done directly on site, i.e. at the location where the plain bearing component is in use. Such a replacement has the further advantage that the sliding layer segments can be replaced with sliding layer segments with a larger diameter in order to compensate for possible gear bore wear or other wear within a plain bearing. During such a replacement, the affected plain bearing pin and the planetary gear running on it can be removed on site, and the diameter and shape of the planetary gear bore can be measured.A matching set of sliding layer segments can then be selected from a range of thicknesses, the old segments removed from the plain bearing pin, and the new segments installed. The parts are then reassembled.

[0039] Further advantages and advantageous embodiments are set forth in the description, the drawings, and the claims. In particular, the combinations of features set forth in the description and the drawings are purely exemplary, so the features may also be present individually or in other combinations. Short character description

[0040] The invention will be described in more detail below with reference to exemplary embodiments illustrated in the drawings. The exemplary embodiments and the combinations shown in the exemplary embodiments are purely exemplary and are not intended to define the scope of the invention. This scope is defined solely by the appended claims.

[0041] They show: Fig. 1: a cross-sectional view of a plain bearing component with a sliding layer; Fig. 2: a cross-sectional view of the plain bearing component of Fig. 1 in a further embodiment; Fig. 3: a cross-sectional view of a plain bearing component with sliding layer segments; Fig. 4: a cross-sectional view of a plain bearing component of Fig. 3 in a further embodiment; and Fig. 5: a cross-sectional view of a plain bearing component of Fig. 3 in a further embodiment. Detailed description of the invention

[0042] In the following, identical or functionally equivalent elements are identified by the same reference symbols.

[0043] Fig. 1 shows a plain bearing component 1. The plain bearing component 1 has a support component 2 made of a base material, which is shown here in the form of a bolt. The support component 2 can also be provided in a different configuration, such as in the form of a sleeve or an inner or outer ring. Depending on the surface on which the plain bearing component 1 is to have a sliding layer 4, such a sliding layer 4 can be applied to the support component 2.

[0044] For the plain bearing component 1 shown here, this is done by metal powder injection molding (MIM) or ceramic powder injection molding (CIM). Metal powder injection molding follows a similar principle to plastic injection molding, using a metal powder and adhesive or binder, and the part is thermally treated after injection molding to solidify it and expel the adhesive. This applies analogously to ceramic powder injection molding. The following describes the production of the sliding layer 4 by metal powder injection molding, with the embodiments applying analogously to sliding layers produced by ceramic powder injection molding.

[0045] In the Fig. In the embodiment shown in Figure 1, the support component 2 is overmolded in the form of a bolt, i.e., the sliding layer 4 is applied around the outer surface of the bolt 2. For this purpose, the bolt 2 is inserted into an injection mold, and then an MIM shot is performed around the bolt in a corresponding mold cavity to produce the sliding layer 4 and the coated bolt or plain bearing component 1. The tool and bolt are preheated.

[0046] The hollow form corresponds to a negative form of the final plain bearing component 1 including the sliding layer 4. If lubrication channels 6 or the like are to be formed in the sliding layer 4, as in Fig. 2, the hollow mold can have corresponding projections or, depending on the demolding option, separate rods or cores can be used.

[0047] Instead of injecting the sliding layer 4 directly around the carrier component 2, the sliding layer can be produced in the form of several segments 8-1, 8-2, 8-3, as described with reference to Fig. 3 - 4 is described.

[0048] These segments 8-1, 8-2, 8-3 are manufactured separately from the bolt 2, meaning that the bolt 2 is not overmolded as a whole. The segments 8-1, 8-2, 8-3 can then be mounted around the bolt 2 (or around or in a sleeve). Fig. 3 - 4 show three segments 8-1, 8-2, 8-3 as examples. However, only two or more than three segments are also possible.

[0049] On the inner side of the segments 8-1, 8-2, 8-3 facing the bolt 2, form-fitting geometries or elements 14-1, 14-2, 14-3 can be molded, such as knobs or projections, with which the respective segment 8-1, 8-2, 8-3 can snap into or be clamped into corresponding elements 16-1, 16-2, 16-3 (e.g., bores or milled recesses / turns) of the bolt 2. These securing elements 14-1, 14-2, 14-3, 16-1, 16-2, 16-3 allow the segments 8-1, 8-2, 8-3 to be secured to the bolt 2 against rotation and displacement. In addition, radial screwing options can be provided, with the threaded holes in bolt 2 and the through holes and countersunk recesses in segment 8-1, 8-2, 8-3.

[0050] It is also possible to provide the segments 8-1, 8-2, 8-3 with puzzle-piece-like edges in order to simultaneously connect them to one another in a form-fitting manner when pressed onto the bolt 2. For this purpose, the segments 8-1, 8-2, 8-3 can have elements 10-1, 10-2, 10-3 and complementary elements 12-1, 12-2, 12-3 at their edge regions, each of which faces another segment 8-1, 8-2, 8-3. These connecting elements 10-1, 10-2, 10-3, 12-1, 12-2, 12-3 thus serve to cooperate to fasten the segments 8-1, 8-2, 8-3 to one another. Geometries are possible that mesh with each other in the circumferential direction and have a circumferential displacement capability, so that the segments 8-1, 8-2, and 8-3, when they first mesh, describe a larger diameter than their fully assembled diameter. As segments 8-1, 8-2, and 8-3 move further into each other until they reach the fully assembled position, these tongue-and-groove geometries then slide further into each other.However, with a small radial expansion, geometries are also possible that interlock with undercuts in the typical shape of puzzle pieces through radial relative movement. Since this also results in an additional displacement component in the circumferential direction during the reduction of the enveloping circle, the thicknesses of such structures are limited, but they can easily achieve a clamping or snapping effect.

[0051] In Fig. 3 and Fig. 5, the segments 8-1, 8-2, 8-3 are each shown as one piece. However, each segment 8-1, 8-2, 8-3 can also be manufactured in two parts, as in Fig. 4. In a first step, a respective carrier 18-1, 18-2, 18-3 can be injection-molded using an MIM process. This is not made of sliding material, but of a low-cost supporting material. Advantageously, an unusually alloyed steel or a non-ferrous metal can be selected here. These materials can be used, for example, to determine when the sliding layer 8-1, 8-2, 8-3 is worn down to this carrier 18-1, 18-2, 18-3 by analyzing the transmission oil for these components. If the carrier 18-1, 18-2, 18-3 is made of a material that is not otherwise found in the transmission, or of a material with alloying elements that are not otherwise found in the transmission, then the analytical detection of these elements in the transmission oil is proof that at least one segment 8-1, 8-2, 8-3 has a worn sliding layer and is running on the carrier material.It is therefore sensible to choose a carrier material that also offers certain emergency running properties, even though it is designed as a support body and not primarily as a sliding layer.

[0052] The sliding layer 8-1, 8-2, 8-3 (e.g., a copper-aluminum alloy or bronze) is then sprayed onto this carrier 18-1, 18-2, 18-3 using MIM. Since the MIM process can produce very precise and complex geometries to the finished dimensions, post-processing is unnecessary in all of the embodiments shown. This two-part construction of each segment 8-1, 8-2, 8-3 results in only a thin layer of the expensive sliding material and a cheaper carrier layer underneath, which, however, is better suited to increasing the stability of the segment and for attaching it to the bolt, and can also serve as a wear indicator.

[0053] As already mentioned with reference to Fig. 2, the sliding layer segments 8-1, 8-2, 8-3 can also be provided with lubrication channels 6-1, 6-2, 6-3. This is shown in Fig. 5. Plain bearing bolts (HPB = hybrid plain bearings) often have oil channels and lubrication pockets in the sliding layer to ensure that the bearing surfaces are separated as hydrodynamically as possible. For this purpose, oil is injected under pressure. Such lubrication pockets (hollow forms in the sliding layer), shown here as an example and designated 6-1, 6-2, 6-3, as well as oil-carrying bores to supply the lubrication pockets, can be formed directly into the segments 8-1, 8-2, 8-3 using MIM, as described above. Subsequent machining to create these would of course also be possible, but is not necessary. After mounting the segments 8-1, 8-2, 8-3, a metal tube can be pressed into the oil channels of segment 8-1, 8-2, 8-3 and bolt 2 to direct the oil exclusively onto the segment 8-1, 8-2, 8-3 instead of underneath it. However, this is not absolutely necessary.Due to its diameter, the outer surface of segment 8-1, 8-2, 8-3 is much larger than the inner surface of segment 8-1, 8-2, 8-3. With the same oil pressure above and below segment 8-1, 8-2, 8-3, the latter would be pressed against pin 2 and not lifted off. A reversal only occurs when the oil outflow on the outside is so large that the pressure there drops significantly. However, this is not in the spirit of a hydrodynamic bearing, whose pressure should only drop at the outflow edge.

[0054] The use of sliding layer segments 8-1, 8-2, 8-3 as shown in Fig.3 to 5, has the advantage that there is no coating of the bolt 2 and no thermal input into the bolt 2. The bolt 2 can be manufactured conventionally mechanically, optionally with additional mechanically manufactured recesses 16-1, 16-2, 16-3 for engaging the segments 8-1, 8-2, 8-3, and / or with additional threaded holes. Thanks to the segmentation without oversized tools, the 8-1, 8-2, and 8-3 segments are manufactured at a high cycle rate using an MIM injection molding machine. They are then simply clipped or screwed on manually.

[0055] Worn units can be reconditioned without rework by removing the sliding segments 8-1, 8-2, and 8-3 and replacing them with new ones. The very expensive bolt 2 can be reused immediately and does not require any dimension modification. Reconditioning is a manual operation and does not require coating or reworking machines. In solutions with directly coated bolts, wear occurs when the sliding layer is worn through, and the base material of the bolt, usually steel, is attacked. This means that the bolt must be over-turned or ground during rework before it can be recoated. The required coating becomes undesirably thicker with each rework.On the other hand, the steel-to-steel contact with the planetary gear bore is prone to damaging the planetary gear through, for example, scuffing and cold welding, and also necessitating extensive rework or repair. On-site repair of the parts is impossible or at least difficult. With the plain bearing component 1 described here, which features replaceable segments 8-1, 8-2, 8-3 with a sliding layer on a support suitable for emergency operation, the planetary gear is protected in the event of wear and enables simple and comparatively cost-effective repair. Furthermore, on-site replacement is possible.

[0056] In case of wear of the gear bore, you can use a set of segments 8-1, 8-2, 8-3 with a slightly larger effective diameter and thus compensate for the resulting play in the bearing when changing the segments 8-1, 8-2, 8-3.

[0057] While sliding sleeves have the disadvantage that they must be fixed axially and radially, a coating has the advantage of fixed positioning, and the system with MIM segments also offers this advantage. Furthermore, sliding sleeves have the disadvantage that their diameter must match the bolt diameter very precisely and fit without play at all temperatures, and in the case of coatings, temperature fluctuations lead to tensions between the layer and the substrate. In contrast, segments 8-1, 8-2, 8-3 can always fit the bolt without play. All they need is a little air space between segment 8-1, 8-2, 8-3 and neighboring segment 8-1, 8-2, 8-3, in the tenths of a millimeter range. While gaps between segment 8-1, 8-2, 8-3 and bolt 2 would not be ideal, gaps between segments 8-1, 8-2, 8-3 are not critical.

[0058] In summary, the plain bearing component and the method for manufacturing the plain bearing component described here provide a simple, fast and cost-effective way to manufacture plain bearing components and to repair these plain bearings if necessary. List of reference symbols 1 plain bearing component 2 support component / bolt 4 Sliding layer 6, 6-1, 6-2, 6-3 lubrication channel 8-1, 8-2, 8-3 sliding layer segment 10-1, 10-2, 10-3 element / connecting element 12-1, 12-2, 12-3 complementary element / connecting element 14-1, 14-2, 14-3 Element / Safety element 16-1, 16-2, 16-3 complementary element / safety element 18-1, 18-2, 18-3 carrier

Claims

[1] Method for producing a plain bearing component (1), in particular a plain bearing bolt, characterized by the steps: Providing a support component (2) consisting of a base material, in particular steel, Metal powder injection molding (MIM) or ceramic powder injection molding (CIM) of a sliding layer (4) on the base material of the carrier component (2) or Metal powder injection molding or ceramic powder injection molding of sliding layer segments (8-1, 8-2, 8-3) and subsequent attachment of the sliding layer segments (8-1, 8-2, 8-3) to the carrier component (2). [2] Method according to claim 1, wherein the step of metal powder injection molding or ceramic powder injection molding of the sliding layer (4) or the sliding layer segments (8-1, 8-2, 8-3) comprises providing a hollow mold and filling the hollow mold with a metal powder-binder mixture or ceramic powder-binder mixture. [3] Method according to claim 2, wherein the method comprises forming lubrication pockets and / or bores (6, 6-1, 6-2, 6-3) in the sliding layer (4) or the sliding layer segments (8-1, 8-2, 8-3) by means of elements provided in the hollow mold. [4] A method according to claim 2 or 3, wherein the method comprises, after providing and filling the hollow mold and demolding, the step of removing the binder and subsequent sintering. [5] Method according to one of claims 2 to 4, wherein the method further comprises forming one or more elements (14-1, 14-2, 14-3) on the side of a sliding layer segment (8-1, 8-2, 8-3) facing the carrier component (2) by means of the hollow mold, wherein the one or more elements (14-1, 14-2, 14-3) are connectable in a form-fitting manner to complementary elements (16-1, 16-2, 16-3) of the carrier component (2). [6] Method according to one of the preceding claims, wherein the method further comprises forming one or more elements (10-1, 10-2, 10-3) on a sliding layer segment (8-1, 8-2, 8-3) by means of the hollow mold, wherein the one or more elements (10-1, 10-2, 10-3) are form-fittingly connectable to complementary elements (12-1, 12-2, 12-3) of a further sliding layer segment (8-1, 8-2, 8-3). [7] Method according to claim 8, wherein the method further comprises attaching at least two sliding layer segments (8-1, 8-2, 8-3) to the carrier component (2), wherein the at least two sliding layer segments (8-1, 8-2, 8-3) are positively connected to one another with their complementary elements (10-1, 10-2, 10-3, 12-1, 12-3, 12-3). [8] Method according to one of the preceding claims, wherein the step of metal powder injection molding or ceramic powder injection molding of sliding layer segments (8-1, 8-2, 8-3) comprises the injection molding of a metallic or ceramic carrier (18-1, 18-2, 18-3) and subsequent injection molding with the metal powder-binder mixture or ceramic powder-binder mixture. [9] Plain bearing component (1), in particular plain bearing bolt, wherein the plain bearing component (1) consists of a carrier component (2) made of a base material, in particular steel, characterized by that a sliding layer (4) produced by metal powder injection molding or by ceramic powder spraying is provided on the base material of the carrier component (2) or that at least two sliding layer segments (8-1, 8-2, 8-3) produced by metal powder injection molding or by ceramic powder spraying are provided around the carrier component (2). [10] Plain bearing component according to claim 9, wherein the sliding layer (4) or the sliding layer segments (8-1, 8-2, 8-3) are produced by means of the method according to one of claims 1 to 8. [11] Plain bearing component according to claim 8 or 9, wherein the sliding layer (4) or the sliding layer segments (8-1, 8-2, 8-3) comprise copper, aluminum, and / or a copper alloy. [12] Plain bearing component according to one of claims 9 to 11, wherein the sliding layer segments (8-1, 8-2, 8-3) have one or more elements (14-1, 14-2, 14-3) on their inner peripheral surface and wherein the carrier component (2) has one or more complementary elements (16-1, 16-2, 16-3) on its outer peripheral surface, wherein the elements (14-1, 14-2, 14-3) of the sliding layer segments (8-1, 8-2, 8-3) and the complementary elements (16-1, 16-2, 16-3) of the carrier component (2) are designed to interact. [13] Plain bearing component according to one of claims 9 to 13, wherein two sliding layer segments (8-1, 8-2, 8-3) have mutually complementary elements (10-1, 10-2, 10-3, 12-1, 12-3, 12-3) which are designed to cooperate to secure the sliding layer segments (8-1, 8-2, 8-3) to the carrier component (2).

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