Device and method for assembling a sliding bearing

Abstract

The invention relates to a device for assembling a sliding bearing (1), in particular a spherical bearing, having an inner ring (2) and a separate outer ring (3), the device comprising a clamping ring (7) which is arranged to receive the outer ring (3), the inner diameter of the clamping ring in its most compressed state at most corresponding to the outer diameter of the outer ring (3). In order to shrink the clamping ring (7) onto the outer ring (3) and to separate the clamping ring (7) from the outer ring (3), a temperature control device (9), in particular in the form of an induction heating device, is provided which heats the clamping ring (7).

Description

Technical Field

[0001] The invention relates to a device for assembling a sliding bearing, in particular a spherical bearing. The invention also relates to a method for assembling a sliding bearing. Background Art

[0002] DE 10 2006 044 637 A1 discloses a spherical bearing having an outer ring and an inner ring which are designed as separate rings. The inner ring of the spherical bearing is held together by two separate clamping rings.

[0003] WO 2011 / 020464 A1 discloses a bearing ring for a rolling bearing or a sliding bearing, which includes a base body and a coating. Here, the base body has a fiber-reinforced plastic having fibers arranged in a plastic matrix, in particular a hardened resin matrix, while the coating material includes ceramic.

[0004] DE 10 2018 200 309 A1 describes a rolling bearing arrangement having an outer ring and an inner ring, the outer ring having an additional support ring which extends at least over an axial subregion of the outer ring which extends concentrically to the axis of rotation of the rolling bearing arrangement.

[0005] Various variants of sliding materials intended for sliding bearings are described, for example, in the publications DE 10 2010 023 647 A1, WO 2015 / 172 781 A1 and DE 10 2008 031 824 B4. Summary of the invention

[0006] The object of the present invention is to further improve the assembly of a plain bearing compared to the prior art with regard to a particularly high level of process reliability and long-term availability of the assembled components.

[0007] According to the invention, this object is achieved by a device which is designed for assembling a plain bearing with a divided outer ring and has the features of claim 1. The object is also achieved by a method for assembling a plain bearing according to claim 6. The configurations and advantages of the invention described below in conjunction with the assembly method also apply accordingly to the device for assembly, and the configurations and advantages of the invention described below in conjunction with the assembly device also apply accordingly to the assembly method.

[0008] The device according to claim 1 is designed for assembling a plain bearing, in particular a plain bearing in the form of a spherical bearing, which has a typically one-piece inner ring and a split outer ring. A split outer ring is understood to be a bearing outer ring having at least one slit. A completely split outer ring, i.e. an outer ring having two diametrically opposite slits, in particular broken grooves, on the circumference of the outer ring also falls within the definition of a split outer ring.

[0009] In order to accommodate the outer ring during assembly, a clamping ring is provided in any case, the inner diameter of which in its most compressed state at most corresponds to the outer diameter of the outer ring. In addition, a temperature control device is provided which is designed to heat the clamping ring, which on the one hand enables the clamping ring to be shrunk onto the outer ring and on the other hand enables the clamping ring to be separated from the outer ring.

[0010] In a preferred embodiment, the temperature control device is an induction heating device, i.e. an inductor. The induction heating device is preferably designed to generate an electric current with a frequency of at least 10 kHz. With the aid of this high-frequency alternating current, the area of ​​the clamping ring close to the surface can be heated in a targeted manner by means of the skin effect. This minimizes the heat input into components that do not have to be heated, in particular the outer ring. In a preferred embodiment of the method, when the clamping ring is heated, the heat input into the outer ring corresponds to at most 20% of the heat input into the clamping ring, in particular not more than 10% of the heat input into the clamping ring.

[0011] The sliding bearing is preferably a spherical bearing, wherein the clamping ring has a cylindrical inner peripheral surface corresponding to the shape of the outer ring. In an advantageous embodiment, the specific electrical conductivity of the clamping ring is higher than the specific electrical conductivity of the outer ring.

[0012] Typically, a method for assembling a sliding bearing comprises the following steps:

[0013] - providing an inner ring as a first bearing ring,

[0014] - providing a second bearing ring, namely the outer ring, which has at least one slit, in particular in the form of a broken groove,

[0015] - lining the outer ring with a sliding lining which is still not hardened at this stage of the method,

[0016] - inserting the inner ring into the outer ring, wherein the outer ring is bent open at least slightly and the sliding lining, in particular in the form of a sliding fabric, is still in the uncured state,

[0017] - shrink the clamping ring onto the outer ring,

[0018] - Hardening of the sliding lining with the clamping ring in place,

[0019] - Heat the clamping ring and remove it from the outer ring.

[0020] The clamping ring is preferably heated by induction both before it is shrunk and at a later point in time for disassembly purposes. The sliding fabric hardens completely when the clamping ring is placed on the outer ring. The clamping ring ensures that the crack does not widen during the entire hardening cycle. After the sliding fabric has hardened, the outer ring remains in the shape imposed by the clamping ring. The crack can be used in a subsequent manufacturing step to indicate the angular position of the outer ring when the sliding bearing is mounted in the surrounding structure.

[0021] A particular advantage of the invention is the fact that the clamping ring is hardly subject to wear, is easy to handle and does not require pretreatment before it is used to assemble a plain bearing. Overall, therefore, the assembly process can be carried out efficiently in the case where one and the same clamping ring can be used for a large number of plain bearings to be assembled successively. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In the following, exemplary embodiments of the present invention are described in more detail with the aid of the accompanying drawings. In the drawings:

[0023] Figure 1 A device comprising a clamping ring for assembling a sliding bearing is shown,

[0024] Figure 2 The plain bearing and the clamping ring are shown in a front view. DETAILED DESCRIPTION

[0025] The plain bearing, which is generally designated by reference numeral 1, is designed as a spherical bearing and comprises an inner ring 2 and an outer ring 3 as plain bearing rings. Compared to the inner ring 2, the outer ring 3 has a broken groove 4 and is therefore considered a separate bearing ring. The sealing ring held in the outer ring 3 is designated by 8.

[0026] The outer ring 3 comprises a metal matrix 5 and a sliding lining 6 in contact with the inner ring 2. The sliding lining 6 comprises a sliding fabric. The components of the sliding fabric are fibers, in particular PTFE and / or carbon fibers, contained in a resin matrix. The central axis of the sliding bearing 1 is denoted by M. The inner ring 2 can be tilted at an angle α relative to the outer ring 3.

[0027] In order to insert the inner ring 2 into the outer ring 3 when the sliding lining 6 has not yet hardened, the outer ring 3 is slightly bent open. Then, the crack 4, that is, the broken groove, is closed again by means of a clamping ring 7, also called a hardening clamp.

[0028] If the temperature of the clamping ring 7 corresponds to the temperature of the outer ring 3, the inner diameter of the clamping ring 7 at most corresponds to the outer diameter of the outer ring 3. Therefore, the clamping ring 7 cannot be assembled on the outer ring 3 in this state.

[0029] In order to enable the clamping ring 7 to be assembled on the outer ring 3, the clamping ring 7 is heated by means of a temperature control device 9 which is designed as an induction heating device and Figure 1 The induction heating device 9, also referred to as an inductor for short, generates an alternating current with a frequency of at least 10 kHz. Figure 1 and Figure 2 In the figure, the annular gap between the inductor 9 and the clamping ring 7 is represented by S p express.

[0030] The high frequency alternating current ensures, by means of the skin effect known per se, that the current flows and therefore also that heating occurs primarily on the surface of the clamping ring 7. The specific conductivity of the clamping ring 7 is higher than that of the outer 3 and inner 2 rings.

[0031] The heated clamping ring 7 is placed on the outer ring 3 of the sliding bearing 1, so that Figure 1 and 2 The arrangement shown. Due to the subsequent cooling of the clamping ring 7, which takes place as soon as the clamping ring 7 is placed on the outer ring 3, the clamping ring 7 generates a significant clamping force on the outer ring 3. In this state, i.e. when the clamping ring 7 is shrunk onto the outer ring, the gap 4 is closed. The sliding lining 6 is completely hardened when the clamping ring 7 is placed on the sliding bearing 1.

[0032] In order to remove the clamping ring 7 after the sliding lining 6 has hardened, the clamping ring 7 is heated again by means of the induction heating device 9, so that only a small amount of heat is introduced into the outer ring 3. Compared with the heat introduced into the clamping ring, the heat introduced into the outer ring 3 does not exceed 10%, so that - also due to the short heating time - the outer ring 3 only heats up slightly, which is practically independent of the change in diameter. In particular, the skin effect already mentioned ensures that the heating rate of the clamping ring 7 is significantly higher than the heat transfer rate from the clamping ring 7 to the outer ring 3. Due to the heat-related expansion of the clamping ring 7 when it is removed, an air gap is also produced between the clamping ring 7 and the outer ring 3, which is not visible in the figure. This air gap acts as an insulator and minimizes the heat transfer between the clamping ring 7 and the outer ring 3.

[0033] Due to the temperature-related expansion of the clamping ring 7, it can be removed from the plain bearing 1 with little effort and, depending on the orientation of the plain bearing 1, the clamping ring 7 can even fall off due to gravity. The outer ring 3 with the hardened sliding lining 6 then has a stable shape, so that no further stabilization of the outer ring 3, for example using additional rings, is required. The clamping ring 7 does not suffer any significant technical compromises during the assembly process and can therefore be used for the process-reliable assembly of a large number of plain bearings 1 of the same type.

[0034] Reference numerals list

[0035] 1 Sliding bearing 2 Inner ring 3 Outer ring 4 Crack, broken groove 5 Base body 6 Sliding lining 7 Clamping ring 8 Sealing ring 9 Temperature control device, inductor α Angle M Central axis S p gap.

Claims

1. A device for assembling a sliding bearing (1) having a plurality of sliding bearing rings (2, 3), namely an inner ring (2) and a separate outer ring (3), the device comprising a clamping ring (7) which is arranged to receive the outer ring (3), the inner diameter of the clamping ring corresponding at most to the outer diameter of the outer ring (3) in the maximum compression state of the clamping ring, and a temperature control device (9) which is arranged to heat the clamping ring (7) so that the clamping ring (7) can be shrunk onto the outer ring (3) and to separate the clamping ring (7) from the outer ring (3).

2. Device for assembling a plain bearing (1) having a plurality of plain bearing rings (2, 3), namely an inner ring (2) and a separate outer ring (3), according to claim 1, characterized in that The temperature control device (9) is designed as an induction heating device.

3. Device for assembling a plain bearing (1) having a plurality of plain bearing rings (2, 3), namely an inner ring (2) and a separate outer ring (3), according to claim 2, characterized in that The induction heating device (9) is designed to generate an electric current having a frequency of at least 10 kHz.

4. Device for assembling a plain bearing (1) having a plurality of plain bearing rings (2, 3), namely an inner ring (2) and a separate outer ring (3), according to any one of claims 1 to 3, characterized in that The sliding bearing (1) is designed as a spherical bearing and the clamping ring (7) has a cylindrical inner peripheral surface.

5. Device for assembling a plain bearing (1) having a plurality of plain bearing rings (2, 3), namely an inner ring (2) and a separate outer ring (3), according to any one of claims 1 to 3, characterized in that The clamping ring (7) has a higher specific electrical conductivity than the outer ring (3).

6. A method for assembling a sliding bearing (1), the method comprising the following steps: - providing a first bearing ring, i.e. an inner ring (2), - providing a second bearing ring, the outer ring (3), which has at least one slit (4), - the outer ring (3) is lined with an unhardened sliding lining (6), - inserting the inner ring (2) into the outer ring (3), wherein: The outer ring (3) is bent open at least slightly and the sliding lining (6) is still in the unhardened state, - shrinking the clamping ring (7) onto the outer ring (3), - hardening the sliding lining (6), - Heating the clamping ring (7) and removing it from the outer ring (3).

7. The method according to claim 6, characterized in that The clamping ring (7) is heated by induction both before the clamping ring is shrunk and before the clamping ring is disassembled.

8. The method according to claim 7, characterized in that The clamping ring (7) is heated primarily on the surface.

9. The method according to claim 8, characterized in that When the clamping ring (7) is heated, the heat input into the outer ring (3) is at most 20% of the heat input into the clamping ring (7).

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