EP3052823A1

EP3052823A1 - Needle bearing arrangement

Info

Publication number: EP3052823A1
Application number: EP14755978.5A
Authority: EP
Inventors: Alexander Stark
Original assignee: Schaeffler Technologies AG and Co KG
Current assignee: Schaeffler Technologies AG and Co KG
Priority date: 2013-10-02
Filing date: 2014-07-30
Publication date: 2016-08-10
Also published as: DE102013225447A1; WO2015048948A1; CN105593547B; CN105593547A; DE102013225447B4

Abstract

The invention is based on the problem of proposing a needle bearing arrangement with improved assembly and/or handling properties and a method for assembling it. To this end, a needle bearing arrangement (1) is proposed with an outer and an inner raceway (2, 3) and with a plurality of needles (4) as rolling bodies, wherein the needles are arranged in a full complement for rolling between the inner and the outer raceway, wherein the rotational axes M of the needles define a pitch circle diameter T of the needle bearing arrangement, and with a cage (5), wherein the cage has a plurality of bar sections (7), wherein the bar sections are arranged between the needles radially spaced apart from the pitch circle diameter on one bar side S, and wherein the bar sections are arranged spaced apart from one another in the circulating direction in such a way that the bar sections form a captive securing means for the needles in the direction of the bar side, wherein the cage has a plurality of holding devices (8), wherein the holding devices are arranged between the needles radially spaced apart from the pitch circle diameter on an opposite side G with respect to the bar side and form a captive securing means for the needles in the direction of the opposite side.

Description

Name of the invention

Needle bearing assembly Description

The invention relates to a needle bearing assembly having the features of the preamble of claim 1 and a method for its assembly.

Needle roller bearings are special forms of rolling bearings and are characterized by needles as rolling elements, in particular, the needles are characterized by a large length-to-diameter ratio. Needle bearings include - like other bearings also - usually an outer and an inner support for tracks of the needle bearing, the needles are arranged between the raceways. Usually, the needles are guided or even held in a cage.

The document DE 10 2005 034 739 A1, which probably forms the closest prior art, describes the mounting of a pivotable lever, wherein the bearing comprises a Wälzkörpereinrichtung. The Wälzkörpereinrichtung has two ring segments, on which rolling surfaces are arranged for rolling elements. The rolling elements are designed as needles and optionally performed in a cage frame or in a Filigrankbehig. In both cases, the maximum possible number of needles on the rolling surface is distributed in the interest of a high load rating by full roll sets.

Field of the invention The invention has for its object to provide a nail bearing assembly with improved assembly and / or handling properties and a method for its assembly. This object is achieved by a needle bearing assembly having the features of claim 1 and by a method having the features of claim 12. Preferred or advantageous embodiments of the invention will become apparent from the dependent claims, the following description and the accompanying drawings.

In the context of the invention, a needle bearing assembly is thus proposed, which is particularly preferably designed as a radial needle bearing assembly. The needle bearing assembly serves to support two partners rotatably or pivotally to each other. In particular, the partners via the needle bearing assembly about a common axis of rotation are pivotable and / or rotatable to each other.

The needle bearing assembly comprises an outer and an inner raceway and a plurality of needles as rolling elements. The needles are arranged for rolling between the inner and the outer raceway and contact them. The needles are designed as rollers and have a length-to-diameter ratio of preferably greater than 4: 1, preferably greater than 6: 1 and in particular greater than 8: 1.

The needles are vollroll ig for rolling between the inner and the outer raceway - also called vollnadelig - arranged. In a full complement arrangement, the needles in the direction of circulation are preferably placed close to each other so that a maximum number of needles can be arranged in the circumferential direction on the inner raceway. Due to the full complement arrangement, the largest possible radial load bearing capacity of the needle bearing arrangement is achieved while at the same time saving space. The needles each have their own axis of rotation, wherein the entirety of the axes of rotation defines a pitch circle diameter of the needle bearing assembly. In particular, in the pitch circle diameter, the needles are arranged immediately adjacent to each other.

The needle bearing assembly further comprises a cage, wherein the cage is particularly preferably designed as a Filigrankbehig. The cage preferably comprises two side sections and a plurality of web sections, wherein the web sections span windows for the needles in the direction of rotation. In each of the windows, exactly one needle is preferably inserted, wherein the web portions are arranged between the needles. The web portions are arranged radially spaced from the pitch circle diameter, this side of the pitch circle diameter being referred to as web side. In particular, the web portions are arranged without overlapping to the pitch circle diameter. It is possible that the web portions are arranged on the radial outer side to the pitch circle diameter as the web side or alternatively on the radial inner side of the pitch circle diameter as the web side. However, the web sections are particularly preferably positioned on the radial inner side to the pitch circle diameter. The web portions are arranged spaced apart in the circumferential direction such that the windows formed therefrom prevent the needles from falling out in the radial direction of the web side. Thus, the web sections form a captive for the needles in the direction of the web page. The captive is important because due to the small diameter of the needles is a very filigree design of the needle bearing assembly is given, so that it comes in the assembly of the needles in the cage by falling out of the needles to misadjustments can be visually poorly recognizable.

In the context of the invention it is proposed that the cage has a plurality of holding devices, wherein the holding devices form a captive for the needles in the direction of the opposite side to the web side. By the holding device is thus achieved that the needles can not accidentally fall out of the cage in an opposite direction. The holding devices are arranged on the opposite side to the web side with respect to the pitch circle diameter between the needles. Particularly preferably, a holding device is arranged in each intermediate space between two needles. Particularly preferably, the needles are positively secured by the holding devices against losing.

It is a consideration of the invention that the falling out of the needles both in the inner and in the outer radial direction is prevented by the integration of an additional holding device. Thus, the invention opens up the possibility that the needles are preassembled in the cage, this optionally undergo a quality inspection and can be subsequently used as a self-holding preassembly assembly in the needle bearing assembly. In particular, falling out of needles or thus incorrect assembly of the needle bearing assembly can be avoided.

In a preferred embodiment of the invention, the holding devices are elastically formed so that a particularly non-destructive placement of the needles in the cages from the direction of the opposite side is made possible. In particular, the holding devices are elastically deformed when inserting the needles and return automatically after insertion into the initial state, so that they form the captive for the needles. For example, the needles are clipped into the cage. Particularly preferably, the opposite side to the web side forms a component side in the assembly of the cage with the needles. The holding devices and the web sections are arranged relative to one another in such a way that the needles in their end position are arranged unclipped and / or rotatable in the windows of the cage. In a possible structural embodiment of the invention, the holding devices each comprise two holding members, wherein the two holding members are arranged axially opposite one another in the cage. In particular, the holding members are arranged on side sections of the cage, such as side rings of the cage, in particular integrally formed. The formation of the holding devices as two holding members opened on the one hand a high loss of security of the needles and on the other hand a simplified loading or inserting the needles. This is achieved in particular by the fact that free ends of the holding members are comparatively easily elastically deflectable when inserting the needles.

Particularly preferably, the two holding members of a holding device in the axial direction to the needle bearing assembly are arranged spaced from each other. In particular, the single retainer has a length less than 30%, preferably less than 20% of the length of the needle. With such a length, the needle can be kept captive and at the same time an unnecessary length of the holding member can be avoided.

The holding members are formed, for example, as holding nubs, retaining lugs or holding partial webs. In one embodiment of the invention, the holding devices, in particular the holding members, are circular in cross-section made of solid material. In this embodiment, the holding members form the holding part webs. In an alternative embodiment, the holding devices, in particular the holding members, in cross-section to the web portions open arc shape. In this embodiment, it is possible to particularly easily deform the outer regions of the arc shape in the circumferential direction and / or the axial direction in order to achieve simple insertion. In a further embodiment of the invention the Halteeinhchtungen, in particular the holding members, in cross-section a triangular shape, in particular a wedge shape, on. One corner of the triangle or the wedge tip is directed in the direction of the webs. Due to the widened base of the triangle or the wedge, a positive lock is formed against a loss of the needle in the direction of the opposite side.

For the selection of the material for the cage several possibilities are given: Thus it is possible that the cage is cage-shaped as a sheet metal cage, as a plastic cage or as a composite material.

In preferred structural embodiments of the cage is in one piece and / or einmaterialig, so constructed of a common material. In possible developments of the invention, the holding means comprise a different material than the web portions, wherein the material of the holding means particularly preferably has a higher elasticity than the material of the web portions to support an elastic deformation when loading the cage with the needles. However, the cage with the web sections and the holding devices is particularly preferably formed integrally from plastic, so that it can be manufactured in a common tool.

Depending on the application, it is possible that the needle bearing assembly is formed as a segment storage, wherein the cage extends over an angular range of preferably less than 180 degrees, in particular less than 90 degrees. Alternatively, the needle bearing assembly is formed as a 360 degree bearing, wherein the cage is preferably formed closed in the direction of rotation. In a possible development of the invention, the needle bearing assembly has at least one sheet metal shell or at least one bearing ring, wherein the sheet metal shell or the bearing ring one of Wearing tracks.

The web portions may be formed as webs, wherein the webs connect the side portions in the axial direction of the needle bearing assembly.

In particular, in the embodiment as a segment storage, it is preferred that each of the web portions at least one, preferably two web members, wherein free ends of the web members are spaced apart in the axial direction. The web organs are arranged in particular on the side sections. The bar organs may e.g. in any variant of the holding members, e.g. designed as Stegnoppen, Stegnasen or as partial webs.

Alternatively or additionally, it is preferred that in the embodiment of the needle bearing assembly is designed as a segment bearing the cage as a frame cage, which has a peripheral frame, wherein the frame is composed of the side portions and two frame sections. Particularly preferably, the cage is formed in a single row, wherein all the rollers are arranged in a row. In other applications, eg with higher loads and a larger axial width, it is preferred that the cage is adapted to receive two, three or more rows of rollers. The cage has for at least one of the rows on the previously described web portions and holding devices. The web sections and / or the holding devices can be arranged, for example, at intermediate ring sections of the cage, in particular be formed. It is particularly preferred for the cage to have the retainers and land portions for some or even all of the rows to utilize the advantages described above for each of the rows. In particular, in the event that all rows have the described web portions and the described holding devices, it is achieved that the falling out of all roles is prevented. Another object of the invention is a method for mounting the needle bearing assembly as described above. The method comprises a pre-assembly step, wherein the cage is equipped with the needles. As already explained, the needles are held captive in the cage. In a main assembly step, the cage equipped with the needles is mounted in the needle bearing assembly.

Advantage of the method is in particular a facilitated assembly of the filled cage with the sheet metal shells or the bearing rings, since no additional effort during assembly must be operated to secure the needles from falling out.

Further features, advantages and effects of the invention will become apparent from the following description of preferred embodiments of the invention and the accompanying figures. Showing:

Figure 1 is a schematic side view of a needle bearing assembly as a first embodiment of the invention;

Figure 2 is a schematic plan view in the radial direction from the outside to the needle bearing assembly;

Figure 3 is a schematic plan view of radially inward of the needle bearing assembly of the preceding figures;

Figure 4 shows an alternative embodiment of the needle bearing assembly in the same representation; Figure 5 shows a further alternative of the needle bearing assembly of the preceding figures, also in the same representation; Figure 6 is a schematic sectional view of a needle bearing assembly as a further embodiment of the invention;

Figure 7 is a schematic view of the side portion of the cage of the needle bearing assembly in Figure 6;

Figure 8 is a radial view of the cage in Figures 6 and 7;

Figure 9 is a schematic three-dimensional view of a double row cage as a further embodiment of the invention.

Identical or corresponding components are provided in the figures with the same reference numerals. 1 shows a highly schematic, in particular not to scale representation of a needle bearing assembly 1 as an embodiment of the invention. The needle bearing assembly 1 includes dashed lines shown an inner and an outer raceway 2, 3, on which a plurality of needles 4 are arranged such that they roll on the raceways 2, 3. The needle bearing assembly 1 implements a radial bearing, so that the inner and the outer raceway 2, 3 or adjoining partners about a main axis of rotation HD can be pivoted relative to each other or rotated. Further, the needle bearing assembly 1 comprises a cage 5, which has two circumferential side portions 6a, b and a plurality of webs 7, which connect the side portions 6a, b with each other. The side sections 6a, b may be formed, for example, as side rings.

The centers M of the axes of rotation of the needles 4 define a pitch circle T, which is coaxial and / or concentric with the main axis of rotation HD is arranged.

The needles 4 are arranged full complement to each other, so that on the inner race 2 a maximum number of needles 4 is arranged. In particular, adjacent needles 4 in the pitch circle T can come into direct contact with each other. In order to allow the full roll, the webs 7 are arranged radially inwardly offset to the pitch circle T. Furthermore, these have a triangular or wedge-shaped shape in the cross section shown, wherein a tip of the triangle or the wedge tip is directed radially outward to fit despite relatively large cross-section in the interstices between the fully roll-arranged needles. The free distance d in the direction of rotation between two webs 7 is smaller than the diameter D of the needles 4 is formed, so that a loss of the needles radially inwardly, ie in the direction of the web side with respect to the pitch circle T is positively prevented.

On the opposite side G to the web side S with respect to the pitch circle T between each two needles 4, a holding device 8 is arranged. The holding devices 8 are designed and arranged in the space between the needles 4, that they do not interfere with the full roll arrangement of the needles 4.

The free distance a between two holding devices 8 in the circumferential direction is smaller than the diameter D of the needles 4 is formed, so that a loss of the needles 4 in the direction of the opposite side G, ie radially outward, positively excluded by the holding devices 8. The holding devices 8 have in the embodiment in Figure 1 has a circular cross-section and are made of solid material. However, the holding devices 8 are not rigid, but elastically deformable. The elastic deformability may relate to a material deformability or to a form deformability. For example, the holding devices 8 can be deflected. The elastic Vernnnbarkeit it is achieved that when inserting the needles 4 in the cage 5, the holding means 8 elastically deformed, for example, be moved to provide in this way sufficient space between the holding means 8 to the needles 4 in the cage. 5 appeal. After inserting the needles 4, the holding devices 8 return to their original position and secure the needles 4 against being lost in the direction of the opposite side G in the form-fitting manner described. In summary, both the webs 7 and the holding devices 8 are formed as Verliersicherungen.

FIG. 2 shows a schematic plan view from radially outside on the cage 5 with the loaded needles 4. It can be seen that the side sections 6a, b respectively carry a holding member 9a, b, which together form one of the holding devices 8 in each case. The holding members 9a, b each extend over less than 10% of the total length L of the needles 4. The length of the holding members 9a, b is particularly dimensioned such that an axial gap Z between the free ends of the holding members 9a, b smaller than the total length L of the needles 4 is. Further, the free distance a between two holding members 9 a, b on one of the side portions 6 a, b is smaller than the diameter D of the needles 4 dimensioned. Thus, the needles 4 are positively held captive in the opposite direction. In FIG. 3, the cage 5 is shown in a plan view from radially inward, wherein it can be seen that the webs 7 connect the side sections 6a, b to one another. Furthermore, it can be seen that the webs 7 are formed in the width in the circumferential direction so that the remaining gap d between two webs 7 is not sufficient to pass one of the needles 4 with the diameter D. Thus, the needles 4 are held by the webs 7 form-locking captive in the web direction. FIG. 4 shows a first possible alternative as a further embodiment of the invention. In FIG. 4, the cross-section of the holding devices 4 is triangular, with one corner of the triangle pointing inwards in the radial direction. The available gap or free distance a between two holding devices 8 h is again smaller than the diameter D of the needles 4 selected. Due to the triangular shape is advantageously achieved that the pointing in the direction of rotation free corners of the holding devices 8 can be elastically deformed to insert the needles 4. Nevertheless, the needles 4 are held securely by the holding means 8 positively. The holding devices 8 in FIG. 4 are also divided into two holding members 9a, b arranged on the side sections 6a, 6 at the edge, as shown in FIG.

A further embodiment of the invention is shown in FIG. 5, wherein, in contrast to the preceding exemplary embodiments, the holding devices 8 have an arcuate shape, wherein the arcuate shape forms approximately 180 degrees of a circular ring segment. The arch form is open radially inwards. In a similar manner as in the triangular shape in Figure 4, the free end portions of the arcuate shape can be deformed when inserting the needles 4 in the cage 5 in a simple manner, so that a loading of the cage 5 by the needles 4 is possible. However, a loss of the needles 4 in the direction of the opposite side G is positively prevented by the holding devices 8. The holding devices 8 in FIG. 5 can also be divided into two holding elements 9a, b, which each have the arcuate shape in cross-section, as shown in FIG.

During assembly of the needle roller bearing assembly 1, the cage 5 is equipped with the needles 4 in a pre-assembly piece. The pre-assembly made of cage 5 and needles 4 is formed self-holding. In particular, the needles 4 are held captive in the cage 5. The stocked cage can eg go through a quality assurance and later be used in the needle bearing assembly 1. This assembly order has the advantage that incorrect assembly due to lost needles 4 are excluded. The needle bearing assembly 1 may be formed as a segment bearing, wherein the cage 5 extends over less than 360 °, for example, less than 180 ° or less than 90 ° in the direction of rotation. Alternatively, the needle bearing assembly 1 may be formed as a 360 ° bearing, in particular a bearing for endless rotation.

In FIG. 6, a further needle bearing arrangement 1 is embodied as a segment bearing as a further exemplary embodiment of the invention. The needle bearing assembly 1 extends over an angular range of about 120 °. The inner race (not shown) is formed by a component, the outer race 3 is arranged on a sheet metal shell 10. The cage 5 is formed as a frame cage and has in the direction of rotation end side frame webs 1 1 a, b, which together with the side sections 6 a, b form a circumferentially continuous frame. The cage 5 holds as in the previous embodiments, a plurality of needles 4, so that they roll on the outer raceway 3 full complement.

FIG. 7 shows a radial plan view of the outside of the cage 5. In this illustration, it can be seen that the radially outer holding members 9a, b are designed as short stubs. Instead webs 7 as web portions are used in the embodiment of Figures 6, 7, 8 web members 12 a, b as web portions which are identical in construction to the holding members 9 a, b formed. In the figure 8 is an axial plan view of one of the side portions 6 a, b shown, wherein the needles 4 are hidden graphically. In the same manner as in Figures 1 to 5, the free distance d between the web members 12 a, b in the circumferential direction and the free distance a of the holding members 9 a, b smaller than the diameter D of the needles 4 formed so that the web organs 12 a, b and the holding members 9 a, b each form a captive.

9 shows a further embodiment of the invention, wherein the cage 5 is formed as a double-row cage 5 and the needles 4 are arranged in two rows R1 and R2, wherein the cage 5 a corresponding number of shots, in this embodiment two shots, for the two rows R1 and R2. Between the rows R1 and R2, a common side portion 6c is arranged and like the side portions 6a, b connected to the frame webs 1 1 a, b.

Each of the side portions 6a, b, c carries holding members 9a, b, which are formed in the same manner as in the embodiment in Figures 6 to 8 as a short stub and form the captive in the pointing radially inward direction. The middle side bar 6c carries the holding members 9b on both sides for both rows R1 and R2. On the radial outer side of the cage 5 webs or web portions are formed, which are hidden in the representation by the needles 4 and which form the captive in the radially outwardly facing direction. Instead of training as a segment cage, the cage 5 may be closed in the direction of rotation and thus form a double-row 360 ° cage.

LIST OF REFERENCE NUMBERS

I needle bearing assembly

2 career

3 career

4 needles

5 cage

6a, b side sections

7 bars

8 holding devices

9a, b holding organs

10 sheet metal shell

I I a, b frame bars

12 a, b Stegorgane

HD main axis of rotation

d free distance between the webs 7 and web organs 12 a, b

T pitch circle

S bridge side

G opposite side

a free distance between the holding devices 8 in

direction of rotation

L total length of the needles 4 in the axial direction

M centers of the axes of rotation of the holding organs

R1, R2 rows of needles 4

Claims

claims

1 . Needle bearing assembly (1) having an outer and an inner raceway (2,3) and a plurality of needles (4) as rolling elements, wherein the needles (4) for rolling between the inner and outer raceway (2,3) roll up The needles (4) with their axes of rotation (M) define a pitch circle diameter (T) of the needle bearing arrangement (1) with a cage (5), the cage (5) having a plurality of web sections (7; 12 a , b), wherein the web portions (7; 12 a, b) on a web side (S) radially spaced to the pitch circle diameter (T) between the needles (4) are arranged and wherein the web portions (7; 12 a, b) in the direction of rotation relative to one another such that the web sections (7, 12 a, b) form a captive securing device for the needles (4) in the direction of the web side (S), characterized in that the cage (5) comprises a plurality of retaining devices (7). 8), wherein the holding means (8) on a Gegense Ite (G) to the web side (S) radially spaced from the pitch circle diameter (T) between the needles (4) are arranged and form a captive for the needles (4) in the direction of the opposite side (G).

2. needle bearing assembly (1) according to claim 1, characterized in that the holding means (8) are elastic and allow mounting of the needles in the cage.

3. needle bearing assembly (1) according to claim 1 or 2, characterized in that the holding means (8) each have two holding members (9 a, b), wherein the two holding members (9 a, b) in the cage (5) axially opposite one another are arranged.

4. needle bearing assembly (1) according to claim 3, characterized in that the holding members (9 a, b) are designed as holding nubs, retaining lugs, or holding part webs.

5. needle bearing assembly (1) according to claim 3 or 4, characterized in that the holding member (9 a, b) assumes a length less than 30%, preferably less than 20% of the length (L) of the needle.

6. Needle bearing assembly (1) according to any one of the preceding claims, characterized in that the holding means (9a, b) are circular in cross section, in cross section in an open arch to the webs or in cross-section in a triangular shape, in particular wedge shape formed.

7. Needle bearing assembly (1) according to any one of the preceding claims, characterized in that the cage (5) is formed as a cage cage, a plastic cage or as a composite material käf ig.

8. needle bearing assembly (1) according to one of the preceding claims, characterized in that the needle bearing assembly is formed as a segment storage.

9. needle bearing assembly (1) according to claim 8, characterized in that the web portions (12 a, b) each as two web members (12 a, b) are formed, wherein the two web members (12 a, b) in the cage (5). are arranged axially opposite one another.

10. needle bearing assembly (1) according to one of the preceding claims, characterized by at least one sheet metal shell or at least one inner ring, wherein the sheet metal shell or the inner ring carries one of the raceways (2,3).

1 1. Needle bearing arrangement (1) according to one of the preceding claims, characterized in that the needles (4) in the cage (5) in a plurality of rows (R1, R2) are arranged, wherein the cage (5) for at least one row, some rows or All rows (R1, R2), the web portions (7, 12 a, b) and the holding means (8).

12. A method for assembling the needle bearing assembly (1) according to any one of the preceding claims, wherein in a pre-assembly step, the cage (5) with the needles (4) is fitted, and in a main assembly step of the needles (4) stocked cage (5) in the needle bearing assembly (1) is mounted.