Bearing for harmonic reducer

Abstract

The utility model relates to the technical field of bearings, in particular to a bearing for 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 for 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 V-shaped retainer 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] This utility model relates to the field of bearing technology, and more specifically to a bearing for use in harmonic reducers. Background Technology

[0002] Robot arms typically employ spatial open-chain linkage mechanisms, where the kinematic pairs (revolute or prismatic joints) are often called joints. The number of joints usually corresponds to the robot's degrees of freedom. Based on the joint configuration and coordinate system, robot actuators can be categorized into Cartesian, cylindrical, polar, and articulated coordinate systems. For anthropomorphic purposes, relevant parts of the robot body are often referred to as the base, waist, arm, wrist, hand (gripper or end effector), and locomotion (for mobile robots), etc.

[0003] With the continuous development of robotics technology, it has been gradually applied in various fields such as industry, agriculture, and daily life. However, the harmonic reducers in existing robots use cross-bearings, which only have a single skeleton oil seal. This reliance on the skeleton oil seal for sealing leads to oil leakage after prolonged operation. Since the operating conditions of harmonic reducers are relatively complex, oil leakage can sometimes be severe, causing seal failure. Furthermore, the cross-bearings lack a cage, resulting in insufficient rigidity and bending resistance. Utility Model Content

[0004] The purpose of this invention is to address the shortcomings of existing technologies by providing a bearing with a reasonable structure and good bending resistance for use in harmonic reducers.

[0005] A bearing for harmonic reducers includes two outer rings, which are double-secured by a fixing mechanism and a guiding mechanism. An inner ring extends beyond the outer rings. A V-shaped cage is provided between the outer and inner rings, containing a plurality of double-row needle rollers. A sealing mechanism with retaining elasticity is provided at one end of each outer and inner ring. The cage design optimizes starting torque by more than 10%, contributing to energy saving and motor stability. The double-row needle roller + cage configuration reduces grease overflow compared to cross-roller bearings (without a cage). It also offers higher bending resistance and is more suitable for use in humanoid robots.

[0006] Ensure adequate lubrication of the bearings to reduce the probability of oil leakage.

[0007] As a further improvement and supplement to the above solution, this utility model also includes the following additional technical features:

[0008] The sealing mechanism consists of a sealing strip, a spring, and a stop bar. The spring is mounted on the sealing strip, which has a multi-sided sealing structure. This results in a good sealing effect.

[0009] The V-shaped angle is between 60 and 90 degrees. The structure is reasonable.

[0010] The sealing strip is made of NBR. It has a long service life.

[0011] One of the outer rings is provided with a sealing groove, which can effectively seal the seal.

[0012] The fixing mechanism is a fastener, and the guiding mechanism is a tapered pin used to control the bearing's precision. This ensures both rigidity and accuracy.

[0013] The following beneficial effects can be achieved by using this utility model:

[0014] The double-row needle roller bearing of this invention has a stiffness that is more than 50% greater than that of the cross-bearing bearing of the prior art, resulting in higher bending resistance and greater suitability for use in humanoid robots.

[0015] The two outer rings are connected by bolts and pins, ensuring rigidity and precision.

[0016] The cage design optimizes starting torque by more than 10%, which is beneficial for energy saving and maintaining motor stability. Starting torque is 20-50% lower than that of the cross-braced design, significantly improving motor performance, reducing overcurrent, and saving energy.

[0017] The double-row needle roller bearing with cage configuration reduces grease leakage compared to cross-roller bearings (without cage). This ensures adequate lubrication of the bearing, thereby reducing the probability of oil leakage and solving the problem of easy seal failure in bearings used in harmonic reducers in existing technologies. Attached Figure Description

[0018] Figure 1 This is the front view of this utility model.

[0019] Figure 2 This is the left view of this utility model. Figure 1 (See AA section view).

[0020] Figure 3 This utility model Figure 2 The image shown is a magnified view of the area along direction B. Detailed Implementation

[0021] The specific embodiments of this utility model will now be described in detail with reference to the accompanying drawings.

[0022] like Figure 1-3 As shown, this utility model is a bearing used in a harmonic reducer.

[0023] The bearing for a harmonic reducer described in this embodiment includes two outer rings 1, each with multiple tapered holes. The two outer rings 1 are double-fastened by a fixing mechanism and a guiding mechanism. An inner ring 2 extends beyond the outer rings 1 for effective positioning, and its chamfered ends facilitate installation and disassembly. A V-shaped retainer 5 is provided between the two outer rings 1 and the inner rings 2, containing several needle rollers 3 arranged in a double row. A sealing mechanism 4 with retaining elasticity is provided at one end of each outer ring 1 and inner ring 2. The outer rings 1 are concave, and the inner rings 2 are convex, matching the retainer 5, resulting in good rigidity, higher bending resistance, and greater suitability for humanoid robots.

[0024] Furthermore, the sealing mechanism 4 comprises a sealing strip 41, a spring 42, and a retaining strip 43. The spring 42 is mounted on the sealing strip 41, which has a multi-sided sealing structure. The retaining strip 43 has an L-shaped structure. The retaining strip 43 is fitted onto the sealing strip 41 and is made of metal, effectively supporting the sealing strip 41. The sealing strip 41 seals with both sides of the outer ring 1, one side of the inner ring 2, and the outer side, effectively preventing dust and oil from entering the bearing. Simultaneously, the sealing strip 41 and the inner ring 2 side have a V-shaped structure with a U-shaped opening on the upper side. The spring 42 is located on the U-shaped opening, maintaining permanent elasticity and locking the sealing mechanism 4 between the outer ring 1 and the inner ring 2.

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

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

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

[0028] Furthermore, the fixing mechanism is a fastener 6, and the guiding mechanism is a tapered pin 7 used to control the bearing accuracy. In this embodiment, the fastener is a bolt, and a connection structure with one outer ring recessed is adopted. The pin 7 is effectively positioned and fastened with bolts, effectively ensuring the rigidity and accuracy of the bearing.

[0029] The above are preferred embodiments of the present utility model and do not limit the scope of protection of the present utility model. Any modifications and improvements made by those skilled in the art based on the design concept of the present utility model should be considered within the scope of protection of the present utility model.

Claims

1. A bearing for use in a harmonic reducer, comprising two outer rings (1), characterized in that: The two outer rings (1) are double-fastened by a fixing mechanism and a guiding mechanism; an inner ring (2) is provided inside the two outer rings (1), and the inner ring (2) extends out of the outer rings (1); a "V" shaped retainer (5) is provided between the two outer rings (1) and the inner ring (2), and several needle rollers (3) are provided inside the retainer (5), and the needle rollers (3) have a double-row structure; a sealing mechanism (4) with retaining elasticity is provided at one end of the outer rings (1) and the inner rings (2).

2. The bearing for a harmonic reducer as described in claim 1, characterized in that: The sealing mechanism (4) consists of a sealing strip (41), a spring (42), and a stop bar (43). The spring (42) is located on the sealing strip (41), and the sealing strip (41) has a multi-sided sealing structure.

3. The bearing for a harmonic reducer as described in claim 1, characterized in that: The angle of the "V" shape is between 60 and 90 degrees.

4. The bearing for a harmonic reducer as described in claim 2, characterized in that: The sealing strip (41) is made of NBR.

5. The bearing for a harmonic reducer as described in claim 1, characterized in that: One of the outer rings (1) is provided with a sealing groove (11).

6. The bearing for a harmonic reducer as described in any one of claims 1-5, characterized in that: The fixing mechanism is a fastener (6), and the guiding mechanism is a tapered pin (7) used to control the bearing accuracy.

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