CN110836223A

CN110836223A - Crossed roller bearing and speed reducer

Info

Publication number: CN110836223A
Application number: CN201911225459.0A
Authority: CN
Inventors: 张连新
Original assignee: Kunshan Quanta Machinery Co ltd; Kunshan Huaheng Welding Co Ltd
Current assignee: Kunshan Quanta Machinery Co ltd; Kunshan Huaheng Welding Co Ltd
Priority date: 2019-12-04
Filing date: 2019-12-04
Publication date: 2020-02-25

Abstract

The invention provides a crossed roller bearing and a speed reducer, wherein the crossed roller bearing comprises an outer ring bearing, an inner ring bearing and a rolling assembly, wherein the inner ring bearing is coaxially arranged with the outer ring bearing; the outer ring bearing is provided with a first outer ring and a second outer ring which are coaxially arranged along the axial direction of the outer ring, the inner diameter of the first outer ring is smaller than that of the second outer ring, the inner ring bearing is positioned on the inner side of the second outer ring, and the rolling assembly is positioned between the inner ring bearing and the second outer ring; a first inner gear ring is arranged on the inner periphery of the first outer circular ring, and a second inner gear ring is arranged on the inner periphery of the inner ring bearing; can directly be applied to NGWN type reduction gear or NN type reduction gear, simultaneously, can reduce in a large number the required axial installation space of NGWN type reduction gear or NN type reduction gear makes reduction gear compact structure, simple, good reliability, and can realize high accuracy, high rigid transmission.

Description

Crossed roller bearing and speed reducer

Technical Field

The invention relates to the field of bearings, in particular to a crossed roller bearing suitable for an NGWN type speed reducer and an NN type speed reducer and the speed reducer with the crossed roller bearing.

Background

The crossed roller bearing is a special type bearing with an inner ring and an outer ring which are mutually divided, and simultaneously, rollers which are arranged in a crossed manner are arranged in a V-shaped groove between the inner ring and the outer ring, so that the inner ring and the outer ring can be prevented from being separated from each other; on the other hand, since adjacent rollers are arranged in a crossed manner, the crossed roller bearing can simultaneously bear axial and radial loads and overturning moments, so that the crossed roller bearing has the characteristics of high precision, high rigidity and the like, and is generally used as a joint bearing in an industrial robot.

Chinese patent No. CN207437721U discloses a crossed needle bearing with internal teeth, in which the width of the inner ring is the same as that of the outer ring, the inner ring is provided with a valve for inserting needle rollers, the valve is fixed by screws, and the inner ring is provided with internal teeth which can perfectly match with a flexible gear of a harmonic reducer, so as to reduce the axial size and meet various requirements of the harmonic reducer for a robot on the bearing; however, the valve is disposed on the inner ring of the crossed needle roller bearing, so that the inner ring is not a complete circle, and a continuous tooth profile cannot be processed on the inner ring, and meanwhile, the inner ring is located on the inner side of the outer ring, and a continuous tooth profile cannot be processed on the outer ring, so that the crossed needle roller bearing cannot be applied to an NGWN type speed reducer and an NN type speed reducer.

In view of the above, there is a need for an improved crossed roller bearing and speed reducer to solve the above problems.

Disclosure of Invention

The invention aims to provide a crossed roller bearing suitable for an NGWN type speed reducer and an NN type speed reducer and a speed reducer with the crossed roller bearing.

In order to achieve the purpose, the invention adopts the following technical scheme: a crossed roller bearing comprises an outer ring bearing, an inner ring bearing and a rolling assembly, wherein the inner ring bearing is coaxially arranged with the outer ring bearing; the outer ring bearing is provided with a first outer ring and a second outer ring which are coaxially arranged along the axial direction of the outer ring, the inner diameter of the first outer ring is smaller than that of the second outer ring, the inner ring bearing is positioned on the inner side of the second outer ring, and the rolling assembly is positioned between the inner ring bearing and the second outer ring; the inner periphery of the first outer circular ring is provided with a first inner gear ring, and the inner periphery of the inner ring bearing is provided with a second inner gear ring.

As a further improved technical scheme of the invention, the outer circumference of the inner ring bearing and the inner circumference of the second outer ring are provided with opposite 90-degree V-shaped grooves, the rolling assembly comprises a plurality of rollers arranged in the V-shaped grooves, and the adjacent rollers are arranged in a cross manner; the second outer ring is provided with a mounting hole communicated with the V-shaped groove along the radial direction of the second outer ring in a penetrating mode, and the crossed roller bearing further comprises a filling piece used for shielding the mounting hole.

As a further improved technical solution of the present invention, a sealing member for sealing a gap between the filler and the mounting hole is provided between the filler and the mounting hole.

As a further improved technical scheme of the invention, the periphery of the filling piece is concavely provided with an annular groove, and the sealing piece is a sealing ring arranged in the annular groove.

As a further improved technical scheme of the invention, the crossed roller bearing also comprises a fixing structure used for fixing the filling piece; the fixing structure comprises two oppositely arranged first jacks, a second jack and a bolt, wherein the two oppositely arranged first jacks are arranged on the outer ring bearing and communicated with the mounting hole, the second jack is arranged on the filling piece in a penetrating mode, and the bolt is matched with the first jack and the second jack simultaneously.

As a further improved technical scheme of the invention, the crossed roller bearing further comprises a framework oil seal arranged between the second outer circular ring and the inner ring bearing, and the framework oil seal is positioned at one end of the second outer circular ring, which is far away from the first outer circular ring; the framework oil seal is a double-lip framework oil seal or a single-lip framework oil seal.

According to the technical scheme, the outer ring bearing is provided with a plurality of first fastening holes for connecting an outer part, and the first fastening holes are uniformly distributed along the circumferential direction.

As a further improved technical solution of the present invention, the first fastening hole includes a threaded hole and a through hole penetrating the outer ring bearing in an axial direction.

As a further improved technical scheme of the invention, the inner ring bearing is provided with a plurality of second fastening holes for connecting an outer part, and the plurality of second fastening holes are uniformly distributed along the circumferential direction.

In order to achieve the above object, the present invention further provides a decelerator which is an NGWN type decelerator or an NN type decelerator including the above cross roller bearing.

The invention has the beneficial effects that: according to the crossed roller bearing, the first inner gear ring is arranged on the inner periphery of the first outer circular ring, the second inner gear ring is arranged on the inner periphery of the inner ring bearing, so that the crossed roller bearing can be directly applied to an NGWN type speed reducer or an NN type speed reducer, such as an NGWN type planetary gear speed reducer, an NN type involute small-tooth-difference speed reducer, an NN type pin tooth cycloidal speed reducer and the like, and meanwhile, the inner gear rings are directly arranged on the crossed roller bearing, so that the cost can be saved, the axial installation space required by the NGWN type speed reducer or the NN type speed reducer can be greatly reduced, the NGWN type speed reducer or the NN type speed reducer is compact in structure, simple and good in reliability, and high-precision and high-rigidity transmission.

Drawings

Fig. 1 is a schematic view of the structure of a crossed roller bearing in the present invention.

Fig. 2 is an exploded view of fig. 1.

Fig. 3 is a schematic view of the structure of fig. 1 from another angle.

Fig. 4 is a sectional view taken along the line a-a in fig. 3.

Fig. 5 is an enlarged view at B in fig. 4.

Fig. 6 is a schematic structural view of an NGWN type planetary gear reducer having crossed roller bearings in the present invention.

Fig. 7 is a schematic view of the structure of fig. 6 at another angle.

Fig. 8 is a sectional view taken along line C-C in fig. 7.

Fig. 9 is a schematic view showing a motion transfer relationship of an NN-type pin gear cycloid speed reducer having a crossed roller bearing according to the present invention.

Detailed Description

The present invention will be described in detail with reference to the embodiments shown in the drawings, and reference is made to fig. 1 to 9, which are preferred embodiments of the present invention. It should be noted that these embodiments are not intended to limit the present invention, and those skilled in the art should be able to make functional, methodical, or structural equivalents or substitutions according to these embodiments without departing from the scope of the present invention.

Referring to fig. 1 to 5, the present invention provides a crossed roller bearing 1, which includes an outer ring bearing 11, an inner ring bearing 12, and a rolling assembly 13 disposed between the outer ring bearing 11 and the inner ring bearing 12.

The outer ring bearing 11 has a first outer ring 111 and a second outer ring 112 coaxially arranged along the axial direction thereof, the inner diameter of the first outer ring 111 is smaller than the inner diameter of the second outer ring 112, and the outer diameter of the first outer ring 111 is the same as the outer diameter of the second outer ring 112.

It is understood that the second outer ring 112 is integrally formed on the sidewall of the first outer ring 111, i.e. the first outer ring 111 and the second outer ring 112 are integrally formed. Meanwhile, the inner circumference of the second outer ring 112 and the side wall of the first outer ring 111 enclose to form a rotating track.

The inner ring bearing 12 is located inside the second outer ring 112, that is, the inner ring bearing 12 is located in the rotation track, so that the inner ring bearing 12 and the outer ring bearing 11 are separately arranged and can rotate relatively, and the stability of the relative rotation of the inner ring bearing 12 and the outer ring bearing 11 is enhanced.

The rolling assembly 13 is located between the inner ring bearing 12 and the second outer ring 112. Specifically, the outer circumference of the inner ring bearing 12 and the inner circumference of the second outer ring 112 are provided with 90 ° opposite V-shaped grooves 14, the rolling assembly 13 includes a plurality of rollers 131 disposed in the V-shaped grooves 14, and the adjacent rollers 131 are arranged in a 90 ° cross arrangement, so that the inner ring bearing 12 and the second outer ring 112 can be prevented from being separated, that is, the inner ring bearing 12 and the outer ring bearing 11 can be prevented from being separated, and the cross roller bearing 1 can simultaneously bear axial and radial loads and overturning moments, so that the cross roller bearing 1 has the characteristics of high precision, high rigidity, and the like.

Further, a first inner gear ring 1111 is disposed on the inner circumference of the first outer ring 111, a second inner gear ring 121 is disposed on the inner circumference of the inner ring bearing 12, one of the inner ring bearing 12 and the outer ring bearing 11 can be used as an output end to output power, and at the moment, the other one is in a fixed state, thus, the crossed roller bearing 1 of the present invention can be directly applied to an NGWN type reduction gear or an NN type reduction gear, such as NGWN type planetary gear reducer, NN type involute few-tooth-difference reducer, NN type needle tooth cycloid reducer, etc., meanwhile, the inner gear ring is directly arranged on the crossed roller bearing 1, so that the cost can be saved, the axial installation space required by the NGWN type speed reducer or the NN type speed reducer can be greatly reduced, the NGWN type speed reducer or the NN type speed reducer is compact and simple in structure and good in reliability, and high-precision and high-rigidity transmission can be realized.

In one embodiment, the inner ring bearing 12 is used as an output end to output power, and the outer ring bearing 11 is in a fixed state; of course, this is not a limitation.

Specifically, the inner diameters of the inner ring bearing 12 and the first outer ring 111, and the tooth shapes, the tooth number differences, and other parameters of the first inner ring gear 1111 and the second inner ring gear 121 may be set according to specific situations.

Next, taking the cross roller bearing 1 applied to the NGWN planetary gear reducer 2 and the NN-type pin cycloid reducer 3 as an example, parameters such as the inner diameters of the inner ring bearing 12 and the first outer ring 111, the tooth shapes of the first inner gear 1111 and the second inner gear 121, the difference in the number of teeth, and the like will be specifically described.

Referring to fig. 6 to 8, an NGWN-type planetary gear reducer 2 having the cross roller bearing 1 is shown, the NGWN-type planetary gear reducer 2 including a sun gear 21, a plurality of planet gears 22 engaged with the sun gear 21, and the cross roller bearing 1 engaged with the plurality of planet gears 22, each planet gear 22 being simultaneously engaged with the first ring gear 1111 and the second ring gear 121. Other structures of the NGWN planetary gear reducer 2 can be adopted as the structures of the existing NGWN planetary gear reducer, and thus, the details are not repeated.

In the present embodiment, each of the planet gears 22 is an integral planet gear, that is, the engaging part of each planet gear 22, which is engaged with the first inner gear ring 1111 and the second inner gear ring 121, is an integral body; of course, the present invention is not limited thereto, and in other embodiments, each of the planet gears may also be a duplex planet gear, that is, each of the planet gears 22 has two engaging parts engaged with the first internal gear 1111 and the second internal gear 121, and the two engaging parts are separately arranged, in which case, the first internal gear 1111 and the second internal gear 121 are engaged with two engaging parts of the duplex planet gear respectively.

In the embodiment where each of the planetary gears 22 is an integral planetary gear, the inner ring bearing 12 and the first outer ring 111 have the same inner diameter, the first inner ring 1111 and the second inner ring 121 have tooth shapes that are set as planetary conical teeth or straight teeth that mesh with the planetary gears 22, and the difference in tooth number is the number of planetary gears 22 in the NGWN type planetary gear reducer 2, for example, when there are 4 planetary gears 22 in the NGWN type planetary gear reducer 2, the difference in tooth number is 4.

In the embodiment in which the inner ring bearing 12 outputs power as an output end, the sun gear 21 rotates to drive the plurality of planet gears 22 to rotate, the plurality of planet gears 22 revolve along the first inner ring gear 1111 of the outer ring bearing 11, and each planet gear 22 rotates around its own axis to drive the inner ring bearing 12 to rotate, thereby achieving the purpose of speed reduction.

Please refer to fig. 9, which shows an NN-type pin gear cycloid reducer 3 with the crossed roller bearing 1, where the NN-type pin gear cycloid reducer 3 includes an eccentric shaft 31, a first cycloid disc 32 sleeved on the eccentric shaft 31, and a second cycloid disc 33 coaxially arranged with the first cycloid disc 32, and the first cycloid disc 32 and the second cycloid disc 33 are circumferentially and fixedly connected. In the process of rotating the eccentric shaft 31, the first cycloid disc 32 and the second cycloid disc 33 are respectively engaged with the first inner gear ring 1111 and the second inner gear ring 121.

At this time, the inner ring bearing 12 and the inner diameter of the first outer ring 111 may be set according to the outer diameter of the corresponding cycloid discs and the moving path thereof, e.g., in the embodiment in which the outer diameter of the second cycloid disc 32 is smaller than the first cycloid disc 32, the inner diameter of the first inner ring 1111 is larger than the inner diameter of the second inner ring 121.

The number of teeth of the first inner gear ring 1111 and the second inner gear ring 121 may be set as long as the rotation angle of the first inner gear ring 1111 relative to the first cycloid discs 32 is different from the rotation angle of the second inner gear ring 121 relative to the second cycloid discs 33 when the eccentric shaft 31 rotates, the tooth form of the first inner gear ring 1111 may be set as pin teeth which are rotatably fixed to the first outer ring 111 and can be engaged with the first cycloid discs 32, and the tooth form of the second inner gear ring 121 may be set as pin teeth which are rotatably fixed to the inner ring bearing 12 and can be engaged with the second cycloid discs 33.

In the embodiment that the inner ring bearing 12 outputs power as an output end, the eccentric shaft 31 rotates to drive the first cycloid disc 32 to perform eccentric motion along the first inner ring gear 1111, the first cycloid disc 32 drives the second cycloid disc 33 to perform eccentric motion synchronously, and the second cycloid disc 33 is engaged with the second inner ring gear 121 in the process of performing eccentric motion to drive the inner ring bearing 12 to rotate, so as to achieve the purpose of speed reduction.

It is understood that, in the embodiment in which the inner ring bearing 12 outputs power as an output side, that is, when the cross roller bearing 1 is applied to an NGWN type speed reducer or an NN type speed reducer, the inner ring bearing 12 is fixedly connected to an output disc in the speed reducer, and the outer ring bearing 11 is fixedly connected to a flange or the like so as to fix the outer ring bearing 11; of course, this is not a limitation.

Further, referring to fig. 2, the second outer ring 112 is radially provided with mounting holes 1121 penetrating therethrough and communicating with the V-shaped groove 14, and the rollers 131 can be inserted into or taken out of the V-shaped groove 14 from the mounting holes 1121 in a crossing manner, so as to facilitate mounting and dismounting of the rollers 131; meanwhile, the mounting hole 1121 is formed in the second outer ring 112, so that the inner circumference of the first outer ring 111 and the inner circumference of the inner ring bearing 12 are both complete surfaces, and an inner ring gear meshed with the planet gear 22 is formed conveniently.

Further, the cross roller bearing 1 further includes a filling member 15 for covering the mounting hole 1121, and after the roller 131 is mounted, the filling member 15 is inserted into the mounting hole 1121 to cover the mounting hole 1121.

It can be understood that the shape of the end of the filling member 15 facing the V-shaped groove 14 is adapted to the shape of the V-shaped groove 14, so as to form a complete annular rolling path for the rolling assembly 13 together with the V-shaped groove 14 after the filling member 15 is plugged into the mounting hole 1121, thereby enhancing the stability of the relative movement between the inner ring bearing 12 and the outer ring bearing 11.

Further, the cross roller bearing 1 further includes a fixing structure 16 for fixing the filling member 15, so as to limit and fix the filling member 15 in the mounting hole 1121, and enhance the stability of fixing the filling member 15.

Specifically, the fixing structure 16 includes two oppositely disposed first insertion holes 161 disposed on the outer ring bearing 11 and communicated with the mounting hole 1121, a second insertion hole 162 disposed through the filling member 15, and a plug 163 simultaneously engaged with the two first insertion holes 161 and the second insertion hole 162, after the filling member 15 is filled in the mounting hole 1121, the second insertion hole 162 is communicated with the two first insertion holes 161, and after the plug 163 is inserted into one first insertion hole 161, the plug 163 passes through the second insertion hole 162 and then passes through the other first insertion hole 161, the filling member 15 can be fixed.

In one embodiment, two first insertion holes 161 are disposed through the outer ring bearing 11 in the axial direction; of course, it is not limited thereto, and it should be understood that only one first insertion hole 161 of the two first insertion holes 161 is disposed to penetrate through, and the plug 163 can be inserted into and removed from the first insertion hole 161 disposed to penetrate through.

Further, a seal 17 for sealing a gap between the filler 15 and the mounting hole 1121 is provided between the filler 15 and the mounting hole 1121, so that the lubricating oil in the V-shaped groove 14 can be prevented from leaking out from the gap between the filler 15 and the mounting hole 1121 to affect the lubricating effect of the rolling assembly 13, that is, the effect of affecting the relative rotation between the inner ring bearing 12 and the outer ring bearing 11.

In one embodiment, an annular groove 151 is concavely formed on the outer periphery of the filling member 15, the sealing member 17 is a sealing ring disposed in the annular groove 151, and the sealing ring seals a gap between the filling member 15 and the mounting hole 1121 while the filling member 15 is inserted into the mounting hole 1121; of course, this is not a limitation.

Further, the crossed roller bearing 1 further comprises a framework oil seal 18 arranged between the second outer ring 112 and the inner ring bearing 12, wherein the framework oil seal 18 is located at one end of the second outer ring 112, which is far away from the first outer ring 111, and can seal the V-shaped groove 14 to prevent the lubricating oil in the V-shaped groove 14 from leaking.

Specifically, the inner circumference of one end of the second outer ring 112 away from the first outer ring 111 is provided with a first receiving groove 1122 that is recessed outward along the radial direction thereof, the outer circumference of the inner ring bearing 12 is provided with a second receiving groove 122 that is recessed and matched with the first receiving groove 1122, and after the inner ring bearing 12 is assembled on the outer ring bearing 11, the first receiving groove 1122 and the second receiving groove 122 jointly form a mounting portion for mounting the framework oil seal 18.

In a specific embodiment, the framework oil seal 18 is a two-lip framework oil seal, and can seal the V-shaped groove 14 to prevent the leakage of the lubricating oil in the V-shaped groove 14, and at the same time, can achieve a dustproof effect.

Referring to fig. 5, in an embodiment where the frame oil seal 18 is a double-lip frame oil seal, the frame oil seal 18 includes a sealing outer ring 181 fitted in the first receiving groove 1122, a sealing inner ring 182 fitted in the second receiving groove 122, a connecting ring 183 connecting the sealing outer ring 181 and the sealing inner ring 182 at an end away from the V-shaped groove 14, a spring ring 184 disposed on a side of the sealing inner ring 182 facing the sealing outer ring 181, a sealing lip 185 disposed on a side of the sealing inner ring 182 facing away from the sealing outer ring 181, and a dust lip 186.

The spring ring 184 is used for locking the seal inner ring 182 to prevent the seal inner ring 182 from loosening, thereby ensuring the sealing performance between the seal inner ring 182 and the inner ring bearing 12.

The seal lip 185 is closer to the V-shaped groove 14 than the dust lip 186, and the seal lip 185 tightly abuts against the outer periphery of the inner ring bearing 12 to prevent the lubricant in the V-shaped groove 14 from leaking; the dust lip 186 is tightly held against the outer periphery of the inner ring bearing 12 to prevent dust, i.e., prevent dust from entering the inside of the cross roller bearing 1, and affecting the service life of the cross roller bearing 1.

Further, referring to fig. 3, a plurality of first fastening holes 113 for connecting an outer member are formed in the outer ring bearing 11, and the plurality of first fastening holes 113 are uniformly distributed along the circumferential direction, so that the outer ring bearing 11 and the outer member can be fixedly connected through the first fastening holes 113, thereby fixing the outer ring bearing 11.

Specifically, the first fastening hole 113 includes a threaded hole 1131 and a through hole 1132 penetrating through the outer ring bearing 11 in the axial direction, the outer ring bearing 11 can be fixedly connected to a flange plate or the like in a speed reducer through the threaded hole 1131, and the cross roller bearing 1 can be directly fixed to a robot or the like through the through hole 1132, and at this time, the cross roller bearing 1 can be directly fixed to the robot or the like, so that the fixed connection between the speed reducer and the robot or the like can be realized, that is, the outer ring bearing 11 can be directly used as a housing of a corresponding speed reducer, the structure of the corresponding speed reducer is simplified, and the cost is reduced.

It can be understood that, when the first fastening hole 113 includes the threaded holes 1131 and the through holes 1132, a plurality of the threaded holes 1131 are uniformly distributed along the circumferential direction, and at the same time, a plurality of the through holes 1132 are uniformly distributed along the circumferential direction, so as to enhance the uniform stability of the connection.

Further, referring to fig. 2, a plurality of second fastening holes 123 for connecting an external member are formed in the inner ring bearing 12, and the plurality of second fastening holes 123 are uniformly distributed along the circumferential direction.

In the embodiment where the inner ring bearing 12 is used as an output end for outputting power, the second fastening hole 123 is used to be fastened and connected with an output disc of a corresponding speed reducer, or the inner ring bearing 12 is directly connected with an actuator on a corresponding mechanical structure through the second fastening hole 123, so as to achieve the purpose of outputting power.

Specifically, the second fastening hole 123 may be provided as a threaded hole so as to fixedly connect the inner race bearing 12 and the outer member by a screw or the like, thereby outputting power.

Further, the present invention also provides a reducer, which is an NGWN type reducer or an NN type reducer, such as: NGWN type planetary gear reducer, NN type involute few-tooth-difference reducer, NN type pin tooth cycloid reducer etc. can reduce in a large number the required axial installation space of NGWN type reducer or NN type reducer makes NGWN type reducer or NN type reducer compact structure, simple, good reliability, and can realize high accuracy, high rigidity transmission.

The reducer comprises the crossed roller bearing 1, and the structure of the crossed roller bearing 1 is as described above, which is not described in detail herein.

In summary, in the cross roller bearing 1 of the present invention, the first inner gear ring 1111 is disposed on the inner circumference of the first outer ring 111, and the second inner gear ring 121 is disposed on the inner circumference of the inner ring bearing 12, so that the cross roller bearing 1 can be directly applied to an NGWN type speed reducer or an NN type speed reducer, such as an NGWN type planetary gear speed reducer, an NN type involute few-tooth-difference speed reducer, an NN type pintooth cycloid speed reducer, and the like, and meanwhile, the inner gear ring is directly disposed on the cross roller bearing 1, which can save cost, and greatly reduce the axial installation space required by the NGWN type speed reducer or the NN type speed reducer, so that the NGWN type speed reducer or the NN type speed reducer has a compact, simple, and good reliability structure, and can implement high-precision and high-rigidity transmission.

It should be understood that although the present description refers to embodiments, not every embodiment contains only a single technical solution, and such description is for clarity only, and those skilled in the art should make the description as a whole, and the technical solutions in the embodiments can also be combined appropriately to form other embodiments understood by those skilled in the art.

The above-listed detailed description is only a specific description of a possible embodiment of the present invention, and they are not intended to limit the scope of the present invention, and equivalent embodiments or modifications made without departing from the technical spirit of the present invention should be included in the scope of the present invention.

Claims

1. A crossed roller bearing comprises an outer ring bearing, an inner ring bearing and a rolling assembly, wherein the inner ring bearing is coaxially arranged with the outer ring bearing; the method is characterized in that: the outer ring bearing is provided with a first outer ring and a second outer ring which are coaxially arranged along the axial direction of the outer ring, the inner diameter of the first outer ring is smaller than that of the second outer ring, the inner ring bearing is positioned on the inner side of the second outer ring, and the rolling assembly is positioned between the inner ring bearing and the second outer ring; the inner periphery of the first outer circular ring is provided with a first inner gear ring, and the inner periphery of the inner ring bearing is provided with a second inner gear ring.

2. The crossed roller bearing of claim 1, wherein: the outer periphery of the inner ring bearing and the inner periphery of the second outer ring are provided with V-shaped grooves which are opposite to each other by 90 degrees, the rolling assembly comprises a plurality of rollers arranged in the V-shaped grooves, and adjacent rollers are arranged in a crossed manner; the second outer ring is provided with a mounting hole communicated with the V-shaped groove along the radial direction of the second outer ring in a penetrating mode, and the crossed roller bearing further comprises a filling piece used for shielding the mounting hole.

3. The crossed roller bearing of claim 2, wherein: and a sealing element used for sealing a gap between the filling piece and the mounting hole is arranged between the filling piece and the mounting hole.

4. The crossed roller bearing of claim 3, wherein: the periphery of the filling piece is concavely provided with an annular groove, and the sealing piece is a sealing ring arranged in the annular groove.

5. The crossed roller bearing of claim 2, wherein: the crossed roller bearing further comprises a fixing structure for fixing the filling piece; the fixing structure comprises two oppositely arranged first jacks, a second jack and a bolt, wherein the two oppositely arranged first jacks are arranged on the outer ring bearing and communicated with the mounting hole, the second jack is arranged on the filling piece in a penetrating mode, and the bolt is matched with the first jack and the second jack simultaneously.

6. The crossed roller bearing of claim 1, wherein: the crossed roller bearing also comprises a framework oil seal arranged between the second outer circular ring and the inner ring bearing, and the framework oil seal is positioned at one end of the second outer circular ring, which is far away from the first outer circular ring; the framework oil seal is a double-lip framework oil seal or a single-lip framework oil seal.

7. The crossed roller bearing of claim 1, wherein: the outer ring bearing is provided with a plurality of first fastening holes used for connecting an outer part, and the first fastening holes are uniformly distributed along the circumferential direction.

8. The crossed roller bearing of claim 7, wherein: the first fastening hole comprises a threaded hole and a through hole which penetrates through the outer ring bearing along the axial direction.

9. The crossed roller bearing of claim 1, wherein: the inner ring bearing is provided with a plurality of second fastening holes used for connecting an outer part, and the second fastening holes are uniformly distributed along the circumferential direction.

10. A speed reducer, characterized in that: the reducer is an NGWN type reducer or an NN type reducer comprising a crossed roller bearing according to any one of claims 1 to 9.