DE102014215739B4 - Double row gear bearing comprising a bearing cage assembly and gear - Google Patents

Abstract

At least two-row gearbox bearing (200) comprising a bearing cage arrangement (201) for an at least two-row gearbox bearing, comprising at least a first cage (214-1) with a first flank (218-1) and a second flank opposite the first flank (218-1) Flank (218-2), and a second cage (214-2), the first cage (214-1) and the second cage (214-2) being rotatable about a common central axis (212), and wherein the first flank (218-1) and the second flank (218-2) each have a different mean radius with respect to the common central axis (212), the first cage (214-1) and the second cage (214-2) being in the radial direction partially overlap, and wherein an average radius of the first cage is less than an average radius of the second cage with respect to the common central axis (212), an outer ring (202), a first inner ring (204-1) and a second inner ring (204-1 ), the first inner ring (204-1) or the second e inner ring (204-2) is supported against the outer ring (202) via a rolling element, the outer ring having a radially continuous bore (220) and a radius of a flank of the first cage (214-2) facing the second cage (214-2) 214-1) is smaller than a radius of an edge of the first cage (214-1) facing away from the second cage (214-2).

Description

Present exemplary embodiments are in the field of bearing cage arrangements with an at least two-row gear bearing.

Rolling bearings with two or more rows are used in a large number of areas of application, for example if a comparatively high load on the bearing is to be expected, or, e.g. designed as an angular contact ball bearing when forces act both radially and axially. Bearings with more than one row of rolling elements, however, require more space than single-row bearings, which in some applications, e.g. can cause problems with gearbox bearings in the field of motor vehicle technology, since installation space can only be available to a limited extent here. Furthermore, for example in the field of motor sports, a more compact design may be desirable, for example in order to improve a ratio between the weight and the dimensions of a vehicle.

According to a conventional solution, there is the possibility of guiding two rows of rolling elements on partial circles of different sizes. As a result, cages, which encompass the rows of rolling elements, can be displaced towards one another in the axial direction such that a radial overlap of the cages can occur. Thus, space in the axial direction can be saved if necessary. However, this solution can be accompanied by an increased requirement for installation space in the radial direction. In addition, other technical fields outside of motor vehicle technology may require less space for a bearing in several directions of expansion.

JP 2007 - 92 860 A. teaches a double row angular contact ball bearing that prevents a backflow of lubricant from occurring near an opening on an outflow side of the lubricant between an inner ring and an outer ring.
US 7 059 777 B2 teaches an arrangement for a ball bearing with a double raceway which is mounted in an outer ring member which is axially spaced from one side with two rows of raceway surfaces in the axial direction.
DE 35 40 224 A1 teaches a double row angular contact ball bearing.
DE 10 2009 019 677 A1 teaches a cage to accommodate rolling elements in a radial roller bearing.
US 2009/0 028 483 A1 teaches a large diameter cage that has an asymmetrical shape, a diameter (outlet diameter) near an opening is larger than a diameter (inflow diameter) near the small diameter cage.
DE 79 07 497 U1 teaches a rolling bearing cage consisting of two cage side rings connected by webs.
DE 10 2013 201 146 A1 teaches a four-row angular contact roller bearing designed as an angular contact ball bearing, the rolling elements of which form rows of rolling elements offset with respect to one another in the axial direction with inclined contact lines.
JP H10-37951 A teaches setting a ratio of the thickness of a raceway groove bottom of an outer ring serving as a fixed side to that of a raceway groove bottom of an inner ring serving as a rotating side to 2.0 to 2.75 to 1.0.
DE 10 2007 034 813 A1 teaches an angular contact ball bearing with an outer and with an inner row of balls and with at least one common bearing ring that guides the two rows of balls.
DE 20 2004 001 454 U1 teaches a double-row roller bearing which has a one-piece bearing ring and a two-part bearing ring in the axial direction.
JP 2011 - 241 978 A. teaches a slope portion formed on an inner periphery of the rim of a large-diameter side holder.
DE 10 2009 057 192 A1 teaches a multi-row ball bearing arrangement with at least one inner bearing ring and at least one outer bearing ring, which are arranged coaxially on a longitudinal axis (AX).

It is therefore desirable to bring about an improved concept for saving installation space.

An at least two-row gearbox bearing meets these requirements in accordance with the independent claim.

It is pointed out that only the exemplary embodiments which relate to all features of the new main claim fall within the scope of protection.

Exemplary embodiments relate to a bearing cage arrangement in an at least two-row gear bearing. The bearing cage arrangement comprises at least a first cage with a first flank and a second flank opposite the first flank, and a second cage. The first and the second cage can be rotated about a common central axis. In addition, the first flank and the second flank each have a different mean radius with respect to the common center axis. The first and the second cage can thereby be displaced towards one another, so that installation space in the axial direction can be reduced, and an additional requirement for installation space in the radial direction can be eliminated. Installation space requirements can thus be further optimized.

In some exemplary embodiments, the first flank and the second flank are firmly connected to one another by a web of the first cage. In addition, the web has a course parallel to the central axis in a first section, and a course inclined at an angle to the central axis in a second section different from the first section. Under certain circumstances, this may allow an increase in the pitch circle radius of an associated row of rolling elements, which may possibly allow a higher number of rolling bodies and, in turn, a higher bearing load of the bearing.

In some embodiments, the angle is at least 30 degrees and at most 40 degrees. Thus, at the same time, a displacement of the rolling elements radially outwards and a stable guidance thereof can be permitted at the same time.

The first cage and the second cage partially overlap in the radial direction. A space requirement in the axial direction can thus be reduced even further.

In some embodiments, the first cage is in sliding contact with a shoulder of a bearing ring. This can possibly contribute to a more stable guidance of the cage or rolling elements and thus allow higher speeds.

In one aspect, exemplary embodiments relate to an at least two-row gearbox bearing. The gearbox bearing comprises said bearing cage arrangement, an outer ring, a first inner ring and a second inner ring. The first inner ring or the second inner ring is supported against the outer ring via a rolling element. Possible applications in specific areas of application, e.g. automotive technology, can be used.

The outer ring has a radially continuous bore. In addition, a radius of a flank of the first cage facing the second cage is smaller than a radius of a flank of the first cage facing away from the second cage. This can possibly simplify the supply of lubricant or, in other words, reduce the obstruction of the same by a cage.

In some exemplary embodiments, a first and a second row of rolling elements of the gearbox bearing each have different pitch circle diameters. This can possibly improve the absorption of asymmetrical loads in an axial direction and a corresponding opposite direction, or it can also form a prerequisite for using different rolling element sizes while at the same time saving installation space.

Some exemplary embodiments relate to a gearbox with the gearbox bearing mentioned. This can possibly result in a more compact construction of the transmission or other components interacting with the transmission, which can lead to improved driving behavior of a motor vehicle in some applications, for example in the field of motorsport (Formula 1, etc.).

Exemplary embodiments relate to a method for a bearing cage arrangement in an at least two-row gear bearing. The method comprises arranging at least a first cage with a first flank and a second flank opposite the first flank, and a second cage. The first flank and the second flank can be rotated about a common central axis on radii of different sizes. The arrangement is such that the first and the second cage are rotatable about the common central axis. A space saving in the axial direction can thus be achieved and at the same time an additional space requirement in the radial direction can be avoided.

• 1 ein doppelreihiges Schrägkugellager gemäß einem Vergleichsbeispiel;
• 2a und 2b eine Lagerkäfiganordnung bei einem zweireihigen Getriebelager gemäß einem Ausführungsbeispiel; und
• 3a und 3b einen Lagerkäfig für eine Lagerkäfiganordnung gemäß einem Ausführungsbeispiel.

Further advantageous refinements are described in more detail below with reference to exemplary embodiments shown in the drawings, to which exemplary embodiments are not limited, however. They show in detail:

• 1 a double row angular contact ball bearing according to a comparative example;
• 2a and 2 B a bearing cage arrangement in a two-row gear bearing according to an embodiment; and
• 3a and 3b a bearing cage for a bearing cage arrangement according to an embodiment.

In the following description of the attached illustrations, the same reference symbols designate the same or comparable components. Furthermore, summarizing reference numerals are used for components and objects which occur several times in an exemplary embodiment or in a representation, but which are jointly described with regard to one or more features. Components or objects that are described with the same or summarizing reference numerals can be designed in the same way with regard to individual, several or all features, for example their dimensions, but possibly also different, unless the description does not explicitly state otherwise.

First, a double row angular contact ball bearing is shown 100 according to a comparative example in 1 . The angular contact ball bearing 100 includes an outer ring 102 , a first inner ring 104-1 and a second inner ring 104-2 . The first inner ring 104-1 is over a first row of rolling elements 106-1 along a first direction of force 108-1 against the outer ring 102 supported. The second inner ring 104-2 is over a second row of rolling elements 106-2 along a second direction of force 108-2 against the outer ring 102 supported. A first diameter 110-1 a rolling element of the first row of rolling elements 106-1 is larger than a second diameter 110-2 a rolling element of the second row of rolling elements 106-2 . The first row of rolling elements 106-1 also runs on a smaller pitch circle around a central axis 112 than the second row of rolling elements 106-2 . A radius of the pitch circle corresponds to a distance from the central axis 112 from an axis of rotation of the rolling element when the rolling element rolls on a raceway.

The first row of rolling elements 106-1 is from a first cage 114-1 , and the second row of rolling elements 106-2 accordingly from a second cage 114-1 at least partially enclosed. The first cage 114-1 stands with one shoulder 122 of the first inner ring 104-1 in sliding contact. The first cage 114-1 and the second cage 114-2 have a combined axial expansion 116 on, the amount of which is partially due to a first cage edge 118-1 and a second cage flank 118-2 being affected. In other words, a reduction in the combined axial expansion 116 at the in 1 shown conventional angular contact ball bearings 100 possibly touching the first side of the cage 118-1 and the second side of the cage 118-2 result and may no longer be possible.

The outer ring 102 also has an oil inlet bore 120 on. Introducing and distributing a lubricant in the angular contact ball bearing 100 can through the first cage flank 118-1 and the second cage flank 118-2 may be difficult.

Some exemplary embodiments are now described in more detail below. Components which have a correspondence in a previous figure are not explained again here with regard to their functionality; rather, only the differences are dealt with.

2a and 2 B show one of a double row gearbox bearing 200 included cage arrangement 201 according to an embodiment. The bearing cage arrangement 201 comprises at least a first cage 214-1 with a first edge 218-1 and one of the first flanks 218-1 opposite second edge 218-2 , and a second cage 214-2 . Here are the first cage 214-1 and the second cage 214-2 around a common central axis 212 rotatable. In addition, the first flank point 218-1 and the second flank 218-2 each have a different mean radius with respect to the common central axis 212 on.

The bearing cage arrangement 201 can, for example, be comprised of a double row angular contact ball bearing (DRACBB), but can also be used under certain circumstances with other double or multi-row bearing types. The flanks of a cage can be ring-shaped around the central axis 212 denote sections of the cage arranged around, and be connected to one another by webs. The first edge 218-1 of the first cage 214-1 and the second flank 218-2 of the first cage 214-1 enclose a rolling element of a first row of rolling elements 206-1 at least partially in the axial direction. The mean radius of a flank is, for example, 0.5 times the sum of an outer radius and an inner radius of the flank (see also here 3a and 3b) . Alternatively, the mean radius is, for example, a distance from a geometric center of a flank cross-section, the cross-sectional plane of which is the center axis 212 includes, perpendicular to the central axis 212 .

In other words, the second edge points 218-2 of the first cage 214-1 a radial indentation. This can allow the second cage 214-2 to the first cage 214-1 axially approach, while touching the second flank 218-2 with the second cage 214-2 to avoid. This can result in a combined axial expansion 216 of the first cage 214-1 and the second cage 214-2 reduced in amount, and a simultaneous increase in installation space in the radial direction may be avoided. In contrast to the one in 2 B shown embodiment have in 2a the first cage 214-1 and the second cage 214-2 a partial overlap in the radial direction. In other words, there is at least one radial plane that is both the first cage 214-1 as well as the second cage 214-2 cuts. Compared to the embodiment in 2 B can at 2a This means that even more space can be saved. The space saving can be, for example, at least 0.5 mm, 1 mm, 4 mm or even more.

The radial indentation of the second flank 218-2 to the central axis 212 can also cause the first row of rolling elements 206-1 is radially displaceable to the outside, and can thus run on a larger pitch circle. As a result, a larger number of rolling elements can be used, which places a load limit on the gearbox bearing 200 can possibly be increased. A radius of the pitch circle corresponds to a vertical distance from the central axis 212 from an axis of rotation of the rolling element. The axis of rotation is the axis about which the rolling element rotates when it rolls over a raceway of a bearing ring and can correspond to an axis of symmetry of the rolling element. In one example, the distance can be between the central axis 212 and a geometric center of the rolling element, which lies on the axis of rotation. In the case of a spherical rolling element, the geometric center corresponds to a center of the sphere.

The gearbox bearing 200 further comprises an outer ring 202 , a first inner ring 204-1 and a second inner ring 204-2 . The first inner ring 204-1 is over the first row of rolling elements 206-1 along a first direction of force 208-1 against the outer ring 202 supported. The second inner ring 204-2 is over a second row of rolling elements 206-2 along a second direction of force 208-2 against the outer ring 202 supported. A first diameter 210-1 a rolling element of the first row of rolling elements 206-1 is larger than a second diameter 210-2 a rolling element of the second row of rolling elements 206-2 . The first row of rolling elements 206-1 also runs on a smaller pitch circle around a central axis 212 than the second row of rolling elements 206-2 . The first row of rolling elements 206-1 is from the first cage 214-1 , and the second row of rolling elements 206-2 accordingly from the second cage 214-1 at least partially enclosed. The first inner ring 204-1 and the second inner ring 204-2 are separably connected to each other, which may make an assembly or maintenance process easier. The first inner ring 204-1 and the second inner ring 204-2 can be connected to a common shaft, for example.

In the 2a and 2 B The exemplary embodiments shown have the outer ring 202 a radially continuous bore 220 on. The hole 220 can be used to supply lubricant or also to remove excess lubricant. In addition, a radius is one of the second cage 214-2 facing flank 218-2 of the first cage 214-1 smaller than a radius of the second cage 214-2 opposite flank 218-1 of the first cage 214-1 . The supply or discharge of lubricant can be simplified or, in other words, a hindrance to it can be reduced by a cage. This can result in a better distribution of a lubricant (oil, grease, etc.), which can reduce wear on the rolling elements or a running surface.

In another embodiment, a radius of the second flank 218-2 be larger than a radius of the first flank 218-1 . The lubricant hole 220 can on the first inner ring 204-1 or second inner ring 204-2 to be appropriate.

At the in 2a The embodiment shown is the first cage 214-1 in sliding contact with a shoulder 222 a bearing ring arranged. In 2a the bearing ring corresponds to the first inner ring 204-1 , but can alternatively also the outer ring 202 correspond. This may lead to more stable guidance of the first cage 214-1 or contribute to the rolling elements and thus allow higher speeds. Speeds can be, for example, in a range of at least 11,000 revolutions per minute.

The in 2a used first bearing cage 214-1 is in 3a and 3b shown again. It shows 3a the first cage 214-1 in an exemplary basic form, and 3b the same basic shape with additional recesses 302 , which each take a rolling element 304 serve. The rolling element 304 is only indicated as a dashed line. The first cage 214-1 has an axial width b on. The first edge 218-1 has an inner diameter Ød and an outside diameter ØD on. The rolling element 304 has a diameter ØW , which is essentially a diameter of a recess 302 corresponds. This can mean the diameter of the recess 302 the diameter ØW of the rolling element can exceed, for example, up to 5 percent. About the rolling element 304 force can take place between the inner ring and outer ring of a bearing. A direction of force in 3b is at an angle α to a normal to the central axis 212 inclined.

In 3b are the first flank 218-1 and the second flank 218-2 through a footbridge 306 of the first cage 214-1 firmly connected. In addition, the bridge has 306 in a first section one to the central axis 212 parallel course, and in a second section different from the first section one to the central axis 212 at an angle β inclined course. In one example, the course of the web is the cutting line 308 a radially outer surface of the web with an axial plane (cf. 3a) , or in another example, a connecting line running within the web and the axial plane of a central radius of the first flank with a central radius of the second flank. The mean radius can, for example, be 0.5 times the sum of the inner radius Ød / 2 and the outer radius ØD / 2 be

Under certain circumstances, this may allow an increase in the pitch circle radius of an associated row of rolling elements, which may result in a higher number of rolling bodies 304 , and in turn can allow a higher load capacity of the bearing.

In some embodiments, the angle is β at least 10, 20 or 30 degrees and at most 40 degrees. Thus, at the same time, a displacement of the rolling elements radially outwards and a stable guidance thereof can be permitted at the same time.

Exemplary embodiments can be used, for example, in a motor vehicle. The motor vehicle can have a transmission with such a transmission bearing, as it is based on 2a or 2 B is described.

A further exemplary embodiment represents a method for a bearing cage arrangement in an at least two-row gearbox bearing. The method comprises arranging at least a first cage with a first flank and a second flank opposite the first flank, and a second cage. The first flank and the second flank can be rotated about a common central axis on radii of different sizes. The arrangement is such that the first and the second cage are rotatable about the common central axis. A space saving in the axial direction can thus be achieved and at the same time an additional space requirement in the radial direction can be avoided.

The above-described embodiments are merely illustrative of the principles of the present invention. It should be understood that modifications and variations in the arrangements and details described herein will be apparent to those skilled in the art. Therefore, it is intended that the invention be limited only by the scope of the following claims and not by the specific details presented with the description and explanation of the embodiments herein.

The features disclosed in the above description, the following claims and the attached figures can be of importance and implemented both individually and in any combination for realizing an exemplary embodiment in its various configurations.

Reference symbol list

100

Angular contact ball bearings

102

Outer ring

104-1

First inner ring

104-2

Second inner ring

106-1

First row of rolling elements

106-2

Second row of rolling elements

108-1

First direction of force

108-2

Second direction of force

110-1

First diameter

110-2

Second diameter

112

Central axis

114-1

First cage

114-2

Second cage

116

Combined axial expansion

118-1

First side of the cage

118-2

Second side of the cage

120

Oil inlet hole

122

shoulder

200

Angular contact ball bearings

201

Bearing cage arrangement

202

Outer ring

204-1

First inner ring

204-2

Second inner ring

206-1

First row of rolling elements

206-2

Second row of rolling elements

208-1

First direction of force

208-2

Second direction of force

210-1

First diameter

210-2

Second diameter

212

Central axis

214-1

First cage

214-2

Second cage

216

Combined axial expansion

218-1

First edge

218-2

Second edge

220

drilling

222

shoulder

302

Recesses

304

Rolling elements

306

web

308

Cutting line

Claims (6)

At least two-row gearbox bearing (200) comprising a bearing cage arrangement (201) an at least two-row gearbox bearing, comprising at least a first cage (214-1) with a first flank (218-1) and a second flank (218-2) opposite the first flank (218-1), and a second cage (214- 2), the first cage (214-1) and the second cage (214-2) being rotatable about a common central axis (212), and the first flank (218-1) and the second flank (218-2) each have a different average radius with respect to the common central axis (212), the first cage (214-1) and the second cage (214-2) partially overlapping in the radial direction, and an average radius of the first cage being smaller than an average radius of the second cage with respect to the common central axis (212), an outer ring (202), a first inner ring (204-1) and a second inner ring (204-1), the first inner ring (204-1) or the second Inner ring (204-2) is supported via a rolling element against the outer ring (202), wobe i the outer ring has a radially continuous bore (220), and a radius of a flank of the first cage (214-1) facing the second cage (214-2) is smaller than a radius of a flank facing away from the second cage (214-2) of the first cage (214-1). Gearbox bearing (200) according to Claim 1 , wherein the first flank (218-1) and the second flank (218-2) are firmly connected to one another by a web (306) of the first cage (214-1) and wherein the web (306) closes one in a first section the central axis (212) has a parallel course, and in a second section different from the first section has a course inclined at an angle to the central axis (212). Gearbox bearing (200) according to Claim 2 , where the angle is at least 30 degrees and at most 40 degrees. Transmission bearing (200) according to one of the preceding claims, wherein the first cage (214-1) is arranged in sliding contact with a shoulder (222) of a bearing ring. Gearbox bearing (200) according to Claim 1 , wherein a first row of rolling elements (206-1) of the gearbox bearing (200) and a second row of rolling elements (206-2) of the gearbox bearing (200) each have different pitch circle diameters. Gearbox with a gearbox bearing (200) according to one of the preceding claims.

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