Bearing of harmonic reducer

Abstract

The invention relates to the technical field of bearings, in particular to a bearing of a harmonic reducer. The operation working condition of the harmonic reducer is relatively complex, and the phenomena of oil seepage and oil leakage are serious sometimes, so that sealing failure is caused. And meanwhile, the cross bearing is not provided with a retainer, so that the rigidity and the bending resistance of the cross bearing cannot meet expected requirements. A bearing of a harmonic reducer comprises two outer rings, and the two outer rings are doubly fastened by a fixing mechanism and a guide mechanism; inner rings are arranged in the two outer rings and extend out of the outer rings; a retainer with an inclined angle is arranged between the two outer rings and the inner ring, a plurality of roller pins are arranged in the retainer, and the roller pins are of a double-row structure; and one ends of the outer ring and the inner ring are provided with sealing mechanisms with keeping elasticity. The starting torque of the retainer can be optimized by more than 10%, which is favorable for saving energy and keeping the stability of the motor. And the arrangement of the double rows of roller pins and the retainer can reduce the overflow of grease.

Description

Technical Field

[0001] The present invention relates to the technical field of bearings, and more particularly to a bearing for a harmonic reducer. Background Art

[0002] The arm of a robot generally adopts a spatial open-chain linkage mechanism, in which the kinematic pairs (rotational pairs or translation pairs) are often called joints, and the number of joints is usually the number of degrees of freedom of the robot. According to the different joint configuration types and motion coordinate forms, the robot actuator can be divided into rectangular coordinate type, cylindrical coordinate type, polar coordinate type and joint coordinate type. For the sake of anthropomorphism, the relevant parts of the robot body are often called base, waist, arm, wrist, hand (gripper or end effector) and walking part (for mobile robots).

[0003] With the continuous development of robot technology, it has been gradually applied in various fields such as industry, agriculture, and life. In the harmonic reducer of the existing robot, a cross bearing is used, and only one skeleton oil seal is set. The seal relies on the skeleton oil seal alone, which leads to oil seepage and oil leakage after the harmonic reducer runs for a long time. The operating conditions of the harmonic reducer are relatively complex, and sometimes the oil seepage and oil leakage will be more serious, which will lead to seal failure. At the same time, the cross bearing has no cage, and its stiffness and bending resistance cannot meet the expected requirements. Summary of the invention

[0004] The purpose of the present invention is to provide a bearing for a harmonic reducer with a reasonable structure and good bending resistance in view of the deficiencies in the prior art.

[0005] A bearing of a harmonic reducer includes two outer rings, which are doubly fastened by a fixing mechanism and a guiding mechanism; an inner ring is arranged inside the two outer rings, and the inner ring extends outside the outer ring; a retaining frame with an oblique angle is arranged between the two outer rings and the inner ring, and a plurality of needle rollers are arranged in the retaining frame, and the needle rollers are of a double-row structure; a sealing mechanism with retaining elastic force is arranged at one end of the outer ring and the inner ring. The design with a retaining frame will optimize the starting torque by more than 10%, which is beneficial to energy saving and maintaining the stability of the motor. The setting of double-row needle rollers + retaining frame can reduce the overflow of grease compared with cross rollers (without retaining frame). Ensure sufficient lubrication of the bearing, thereby reducing the probability of oil seepage and leakage.

[0006] As a further improvement and supplement to the above solution, the present invention also includes the following additional technical features: The obliquely arranged retaining frame is arranged in a "V" shape, which has higher bending resistance and is more suitable for use in humanoid robots.

[0007] The sealing mechanism comprises a sealing strip, a spring and a retaining strip, the spring is arranged on the sealing strip, and the sealing strip is a multi-side sealing structure, so the sealing effect is good.

[0008] The V" angle is between 60 and 90 degrees. The structure is reasonable.

[0009] The material of the sealing strip is NBR, which has a long service life.

[0010] A sealing groove is arranged on one of the outer rings, which can effectively seal.

[0011] The fixing mechanism is a fastener, and the guiding mechanism is a tapered pin shaft used to control the bearing accuracy, thereby ensuring rigidity and accuracy.

[0012] The following beneficial effects can be achieved by using the present invention: The double-row needle roller bearing of the present invention has a stiffness greater than that of the cross bearing of the prior art by more than 50%, has a higher bending resistance and is more suitable for use in humanoid robots.

[0013] The two outer rings are connected by screws and pins to ensure rigidity and precision.

[0014] The design with cage will optimize the starting torque by more than 10%, which is beneficial to energy saving and maintaining motor stability. The starting torque is 20-50% smaller than the cross-cross design, which greatly improves the performance of the motor, reduces overcurrent and saves energy.

[0015] The double-row needle roller + cage setting can reduce grease overflow compared to the cross roller (without cage), ensuring sufficient lubrication of the bearing, thereby reducing the probability of oil seepage and leakage, and solving the problem of easy sealing failure of bearings used in harmonic reducers in the prior art. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 It is a structural schematic diagram of the present invention.

[0017] Figure 2 It is the front view of the present invention.

[0018] Figure 3 It is a left view of the present invention ( Figure 2 AA section shown).

[0019] Figure 4 The present invention Figure 3 The B-direction enlarged view is shown. DETAILED DESCRIPTION

[0020] The specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0021] like Figure 1-4 As shown, the present invention is a bearing for a harmonic reducer.

[0022] The bearing of the harmonic reducer described in this embodiment includes two outer rings 1, and the outer ring 1 is provided with a structure of multiple tapered holes. The two outer rings 1 are doubly fastened by a fixing mechanism and a guiding mechanism; the inner ring 2 is provided inside the two outer rings 1, and the inner ring 2 extends outside the outer ring 1, which can effectively be positioned, and the structure of the chamfered ends of the inner ring 2 is convenient for installation and disassembly; a retainer 5 with an oblique angle is provided between the two outer rings 1 and the inner ring 2, and a plurality of needle rollers 3 are provided inside the retainer 5, and the needle rollers 3 are double-row structures; a sealing mechanism 4 with retaining elastic force is provided at one end of the outer ring 1 and the inner ring 2. The outer ring 1 is a concave structure, and the inner ring 2 is a convex structure, which matches the retainer 5, has good rigidity, higher bending resistance and is more suitable for use in humanoid robots.

[0023] Furthermore, the obliquely arranged retaining frame 5 is arranged in a "V" shape, which has good bending resistance.

[0024] Furthermore, the sealing mechanism 4 is composed of a sealing strip 41, a spring 42 and a stopper 43. The spring 42 is arranged on the sealing strip 41. The sealing strip 41 is a multi-side sealing structure, and the stopper 43 is an L-shaped structure. The stopper 43 is sleeved on the sealing strip 41, and the material of the stopper 43 is metal, which can effectively support the sealing strip 41. The sealing strip 41 is sealed with both sides of the outer ring 1, with one side of the inner ring 2, and with one side of the outer side, effectively preventing dust and oil from entering the inner side of the bearing. At the same time, a V-shaped structure is arranged on the sealing strip 41 and the inner ring 2, and a U-shaped opening is arranged on the upper side of the V-shaped structure. The spring 42 is located on the U-shaped opening to maintain permanent elastic force and lock the sealing mechanism 4 between the outer ring 1 and the inner ring 2.

[0025] Furthermore, the V" angle is between 60-90 degrees.

[0026] Furthermore, the material of the sealing strip 41 is NBR.

[0027] Furthermore, a sealing groove 11 is provided on one of the outer rings 1, and an O-ring or a sealing ring is provided on the sealing groove 11 for sealing.

[0028] Furthermore, the fixing mechanism is a fastener 6, and the guide mechanism is a tapered pin 7 for controlling the bearing precision. In this embodiment, the fastener is a bolt, and a connection structure is adopted in which one side outer ring is sunk, the pin 7 is effectively positioned, and is fastened with a bolt, thereby effectively ensuring the rigidity and precision of the bearing.

[0029] The above are preferred embodiments of the present invention, which do not limit the protection scope of the present invention. Any modifications and improvements made by those skilled in the art based on the design ideas of the present invention should be regarded as within the protection scope of the present invention.

Claims

1. A bearing for a harmonic reducer, comprising two outer rings (1), characterized in that: The two outer rings (1) are doubly fastened by a fixing mechanism and a guiding mechanism; an inner ring (2) is arranged inside the two outer rings (1), and the inner ring (2) extends outside the outer ring (1); a retaining frame (5) with an oblique angle is arranged between the two outer rings (1) and the inner ring (2), and a plurality of needle rollers (3) are arranged inside the retaining frame (5), and the needle rollers (3) are of a double-row structure; and a sealing mechanism (4) with retaining elastic force is arranged at one end of the outer ring (1) and the inner ring (2).

2. The bearing of the harmonic reducer according to claim 1, characterized in that: The retaining frame (5) arranged at an oblique angle is arranged in a "V" shape.

3. The bearing of the harmonic reducer according to claim 1, characterized in that: The sealing mechanism (4) comprises a sealing strip (41), a spring (42) and a retaining strip (43); the spring (42) is arranged on the sealing strip (41); and the sealing strip (41) is a multi-side sealing structure.

4. The bearing of the harmonic reducer according to claim 2, characterized in that: The "V" angle is between 60 and 90 degrees.

5. The bearing of the harmonic reducer according to claim 3, characterized in that: The material of the sealing strip (41) is NBR.

6. The bearing of the harmonic reducer according to claim 1, characterized in that: A sealing groove (11) is provided on one of the outer rings (1).

7. The bearing of a harmonic reducer according to any one of claims 1 to 6, characterized in that: The fixing mechanism is a fastener (6), and the guiding mechanism is a tapered pin (7) for controlling the bearing accuracy.

Images