Lightweight crossed roller bearing

Abstract

The utility model relates to the technical field of bearings, in particular to a lightweight crossed roller bearing. The utility model provides a light-weight crossed roller bearing, which comprises a rigid outer ring, an outer ring bottom surface, an outer slide way, a rigid inner ring, an inner slide way and crossed balls, one end of the rigid inner ring is sleeved with the rigid outer ring, the outer slide way is arranged inside the rigid outer ring, the inner slide way is arranged outside the rigid inner ring, and the crossed balls are arranged in the outer slide way. A plurality of crossed balls are arranged between the outer slide way and the inner slide way, and one side of the rigid inner ring is the bottom surface of the outer ring. The rigid inner ring is fixedly connected with the speed reducer part rigid wheel through the connecting screw holes, the bottom face of the outer ring is directly and fixedly connected with the speed reducer shell through welding, the bearing is correspondingly and fixedly connected with the speed reducer part rigid wheel and the speed reducer shell, and the overall assembly size of the speed reducer can be reduced; meanwhile, relative displacement between the crossed bearing and the shell is prevented, and the transmission precision of the bearing reducer is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of bearings, in particular to a lightweight cross roller bearing. Background Art

[0002] Due to its own characteristics, crossed roller bearings can withstand loads in various directions such as axial loads, radial loads and torque loads, and can operate normally under high rigidity and high speed conditions, and can still maintain its rotation accuracy after pressure is applied. Therefore, it is widely used in the field of harmonic reducers inside industrial robots and is an important component of harmonic reducers. The rigid wheel and flexible wheel on the harmonic reducer are respectively connected to the outer ring and inner ring of the cross bearing, so that the rigid wheel and the flexible wheel can rotate asynchronously to achieve the rotation output effect after deceleration. When the harmonic reducer is working, the rigid wheel and the flexible wheel will rotate relative to each other. In order to ensure the stability of the overall rotation, cross bearings are generally used.

[0003] The existing cross bearing is made of GCr15, and the inner and outer rings are provided with connecting threaded holes, so that the walls of the inner and outer rings of the cross are relatively thick. Naturally, the mass of the cross bearing will be heavier, which makes the mass of the reducer larger. The mechanical arm equipped with these reducers will also have a large moment of inertia when rotating. The large moment of inertia will have a negative impact on the mechanical arm. In addition, the weight of the existing cross bearing accounts for half of the weight of the harmonic reducer while meeting the relevant technical standards.

[0004] Therefore, it is necessary to design a cross roller bearing that can reduce installation space and be lightweight. Utility Model Content

[0005] In order to overcome the shortcomings that the existing cross bearings are made of GCr15 and both the inner and outer rings are provided with connecting threaded holes, which makes the reducer mass larger and the mechanical arms equipped with these reducers have a large moment of inertia when rotating, and the large moment of inertia will have a negative impact on the mechanical arms, the utility model provides a cross roller bearing that can reduce the installation space and is lightweight.

[0006] The technical implementation scheme of the utility model is: a lightweight crossed roller bearing, including a rigid outer ring, an outer ring bottom surface, an outer slide, a rigid inner ring, an inner slide and crossed balls, the rigid outer ring is sleeved on one end of the rigid inner ring, the outer slide is arranged inside the rigid outer ring, the inner slide is arranged outside the rigid inner ring, a number of crossed balls are arranged between the outer slide and the inner slide, and one side of the rigid inner ring is the outer ring bottom surface.

[0007] Optionally, after the rigid outer ring and the rigid inner ring are assembled, a cavity is formed between the outer slideway and the inner slideway, and the cross ball is in the cavity formed by the outer slideway and the inner slideway.

[0008] Optionally, the two crossed balls are distributed vertically and crosswise.

[0009] Optionally, a sealing member is further included, and two of the sealing members are arranged between the rigid outer ring and the rigid inner ring.

[0010] Optionally, a plurality of connecting screw holes are circumferentially formed on a side of the rigid inner ring away from the bottom surface of the outer ring.

[0011] Optionally, a retaining frame is further included, and the retaining frame is arranged in the cavity formed by the outer slideway and the inner slideway, and the retaining frame is sleeved on the outer side of the cross ball.

[0012] Compared with the prior art, the utility model has the following advantages: the rigid inner ring is fixedly connected to the rigid wheel of the reducer component by connecting screw holes, and the bottom surface of the outer ring is directly fixedly connected to the reducer housing by welding, so that the bearing is relatively fixedly connected to the rigid wheel of the reducer component and the reducer housing respectively, which can reduce the overall assembly volume of the reducer, and at the same time prevent the cross bearing and the housing from relative displacement, thereby improving the transmission accuracy of the bearing reducer. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 It is a three-dimensional structural schematic diagram of the utility model.

[0014] Figure 2 It is a three-dimensional structural schematic diagram of the rigid outer ring, the rigid inner ring and the connecting screw holes of the utility model.

[0015] Figure 3 It is an exploded view of the rigid outer ring, rigid inner ring and seal of the utility model.

[0016] Figure 4 It is a three-dimensional cross-sectional structural schematic diagram of the outer ring bottom surface, inner slideway and cross ball of the utility model.

[0017] In the above figures: 1. rigid outer ring, 2. outer ring bottom surface, 3. outer slide, 4. rigid inner ring, 5. connecting screw holes, 6. inner slide, 7. cross ball, 8. seal, 9. cage. DETAILED DESCRIPTION

[0018] In order to make the purpose, technical solution and advantages of the utility model clearer, the utility model is further described in detail below in combination with specific implementation methods and with reference to the accompanying drawings. It should be understood that these descriptions are only exemplary and are not intended to limit the scope of the utility model. In addition, in the following description, the description of well-known structures and technologies is omitted to avoid unnecessary confusion of the concept of the utility model.

[0019] Embodiment: A lightweight cross roller bearing, see Figure 1-Figure 4 As shown, it includes a rigid outer ring 1, an outer ring bottom surface 2, an outer slide 3, a rigid inner ring 4, an inner slide 6 and a cross ball 7. One end of the rigid inner ring 4 is sleeved with the rigid outer ring 1. The rigid inner ring 4 and the rigid outer ring 1 are both made of high-carbon chromium bearing steel, which has good hardness, wear resistance and hardenability, so that the rigid inner ring 4 and the rigid outer ring 1 can withstand a load of sufficient strength during the operation of the bearing to prevent plastic deformation or fracture. The rigid outer ring 1 is provided with an outer slide 3 inside, and the rigid inner ring 4 is provided with an outer slide 3 outside. An inner slideway 6 is arranged, and a plurality of cross balls 7 are arranged between the outer slideway 3 and the inner slideway 6, and two adjacent cross balls 7 are vertically cross-distributed. After the rigid outer ring 1 and the rigid inner ring 4 are assembled, a cavity is formed between the outer slideway 3 and the inner slideway 6. The cross balls 7 are in the cavity formed by the outer slideway 3 and the inner slideway 6. The cross sections of the outer slideway 3 and the inner slideway 6 are both V-shaped, which can limit the running track of the cross balls 7 and effectively prevent the rigid outer ring 1 and the rigid inner ring 4 from turning left when the bearing rotates. Right beating, the left side of the rigid inner ring 4 is the outer ring bottom surface 2, and the rigid inner ring 4 is provided with twelve connecting screw holes 5 along the circumferential direction away from the right side. Two seals 8 are arranged between the rigid outer ring 1 and the rigid inner ring 4. The seal 8 is annular. The seal 8 is used to block the gap between the rigid outer ring 1 and the rigid inner ring 4 to prevent dust from entering the gap between the rigid outer ring 1 and the rigid inner ring 4 and affecting the operation of the cross ball 7. The seal 8 is made of nitrile rubber, which is suitable for oil environment and has good oil resistance and wear resistance, so that the seal 8 can protect the bearing for a long time when the bearing runs for a long time. A retainer 9 is arranged in the cavity formed by the outer slide 3 and the inner slide 6. The retainer 9 is sleeved on the outside of the cross ball 7. The retainer 9 is made of brass, has good strength and toughness, and is suitable for occasions requiring higher mechanical strength, so that when the bearing runs for a long time and under high strength conditions, the cross ball 7 can keep running in the track formed by the outer slide 3 and the inner slide 6.

[0020] During assembly, the end face of the rigid inner ring 4 is provided with a connecting screw hole 5. The rigid inner ring 4 and the reducer component rigid wheel are sleeved together by using bolts to pass through the connecting screw holes 5, and then the bolts are tightened to achieve a fixed connection between the rigid inner ring 4 and the reducer component rigid wheel. Like the existing cross roller bearing, the rigid outer ring 1 is connected by bolts, and the rigid outer ring 1 does not adopt a method of setting threaded holes, which reduces the use of bolts in the process of assembling the rigid outer ring 1. Instead, the outer ring bottom surface 2 of the bearing is directly fixedly connected to the reducer housing by welding. This new connection method reduces the space occupied by the cross bearing during the process. Since both bolt connection and welding are relatively fixed connection methods, and the reducer is installed The bearing will basically not be disassembled, and direct welding can prevent the cross bearing and the housing from relative displacement, thereby improving the transmission accuracy of the bearing reducer. When the bearing is running, the rigid outer ring 1 and the rigid inner ring 4 rotate relative to each other, and the cross ball 7 rolls in the cavity between the rigid outer ring 1 and the rigid inner ring 4, converting the sliding friction that should exist into rolling friction, making the rotation smoother. At the same time, in order to enhance the smoothness of the bearing rotation, the cavity between the rigid outer ring 1 and the rigid inner ring 4 is filled with grease. Generally, the outer ring does not rotate, but the inner ring rotates. The grease is used to reduce the friction of the cross ball 7 sliding in the cavity between the rigid outer ring 1 and the rigid inner ring 4, thereby reducing the loss of capacity during the transmission process.

[0021] The above embodiments are only for illustrating the technical concept and features of the utility model, and their purpose is to enable people familiar with the technology to understand the content of the utility model and implement it accordingly, and they cannot be used to limit the protection scope of the utility model. Any equivalent changes or modifications made according to the spirit of the utility model should be included in the protection scope of the utility model.

Claims

1. A lightweight crossed roller bearing, characterized by: The invention comprises a rigid outer ring (1), an outer ring bottom surface (2), an outer slideway (3), a rigid inner ring (4), an inner slideway (6) and cross balls (7); the rigid outer ring (1) is sleeved on one end of the rigid inner ring (4); the outer slideway (3) is arranged inside the rigid outer ring (1); the inner slideway (6) is arranged outside the rigid inner ring (4); a plurality of cross balls (7) are arranged between the outer slideway (3) and the inner slideway (6); and one side of the rigid inner ring (4) is the outer ring bottom surface (2).

2. A lightweight cross roller bearing according to claim 1, characterized in that: After the rigid outer ring (1) and the rigid inner ring (4) are assembled, a cavity is formed between the outer slideway (3) and the inner slideway (6), and the cross ball (7) is in the cavity formed by the outer slideway (3) and the inner slideway (6).

3. A lightweight cross roller bearing according to claim 2, characterized in that: Two adjacent cross balls (7) are vertically cross-distributed.

4. A lightweight cross roller bearing according to claim 3, characterized in that: It also includes a sealing member (8), and two of the sealing members (8) are arranged between the rigid outer ring (1) and the rigid inner ring (4).

5. A lightweight cross roller bearing according to claim 4, characterized in that: A plurality of connecting screw holes (5) are provided along the circumferential direction on a side of the rigid inner ring (4) away from the outer ring bottom surface (2).

6. A lightweight cross roller bearing according to claim 5, characterized in that: It also includes a retaining frame (9), which is arranged in a cavity formed by the outer slideway (3) and the inner slideway (6), and the retaining frame (9) is sleeved on the outside of the cross ball (7).

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