Parallel flexible cylinder deformation and dynamic loading flexible bearing dynamic performance testing device

Abstract

The utility model discloses a flexible bearing dynamic performance test device with parallel flexible cylinder deformation and dynamic loading. Two pairs of flexible bearings are respectively pressed into the two ends of the inner hole of the flexible cylinder with equal diameters, and are respectively installed on the motor shafts at the two ends of the double-headed motor through two pairs of wave generators with mutually perpendicular long axes, so that four sets of flexible bearings can be installed in parallel under the same power source, and the dynamic performance test can be carried out simultaneously under the same rotation speed and flexible cylinder deformation and dynamic load. Utilizing the circularity-preserving feature of the middle section of the flexible cylinder, a plurality of connecting screws with sharp steel needles or self-tapping threads at one end are inserted or screwed into the small holes on the circumference of the middle section of the flexible cylinder, and the other end of the connecting screw is fixed on the semi-cylindrical bracket. The dynamic performance changes of each pair of flexible bearings are measured by vibration, noise, temperature, rotation speed and tension sensors.

Description

Technical Field

[0001] The utility model relates to the technical field of rolling bearing performance detection, in particular to a flexible bearing dynamic performance test device with parallel flexible cylinder deformation and dynamic loading, which simulates the actual loading condition of the flexible bearing in a harmonic reducer to conduct batch dynamic performance tests. Background Art

[0002] Harmonic reducers are core components of industrial manipulators and robots, and their life and precision have an important impact on the performance of the equipment. Compared with transmission methods such as gears, chains and belts, harmonic transmission has the characteristics of large transmission ratio and small size. Flexible bearings and flexible wheels are the two flexible components of harmonic reducers, and are also one of the main factors for the life and precision of harmonic reducer transmission. Compared with ordinary rolling bearings, the inner and outer rings of the flexible bearings used in harmonic reducers are very thin. After the non-circular wave generator is installed, it is forced to change from a circular shape to a non-circular shape, and the load-bearing area of ​​the flexible bearing in the working state rotates synchronously with the long axis position of the wave generator, that is, it is loaded with dynamic load, and the outer ring of the flexible bearing is also subjected to alternating bending stress during operation. Therefore, in addition to failures such as wear and pitting, flexible bearings will also suffer from bending fatigue failure.

[0003] With the popularization of intelligent manufacturing, the application conditions of robots and manipulators are becoming more and more demanding, and the failure problem of flexible bearings for harmonic reducers is becoming increasingly prominent. At present, the research on flexible bearings for harmonic reducers at home and abroad mainly focuses on theoretical analysis, and the understanding of their failure modes and mechanisms is insufficient. The test of flexible bearings is mainly based on the whole machine test of harmonic reducers. However, in the whole machine test, in addition to the failure of flexible bearings, there are also failures of other components such as flexible wheels. There are too many uncontrollable factors, which interfere with the failure analysis and evaluation of flexible bearings. Due to the unique follow-up loading mode of flexible bearings for harmonic reducers, there are currently very few performance test devices that can truly simulate the loading of flexible bearings for harmonic reducers. Patent CN105758642A uses a rotating follow-up loading mechanism to load the flexible bearing. The loading mechanism rotates at high speed with the main shaft, but the loading mechanism is larger, heavier, and has higher power consumption than the tested flexible bearings. It can only perform a single set of flexible bearing tests, which is inefficient and cannot be tested in batches like ordinary bearings. Utility Model Content

[0004] In view of the existing technical defects, the utility model provides a parallel flexible bearing dynamic performance test device based on the core principle of the invention patent application publication number CN 117330313 A, which can simultaneously perform dynamic performance tests on four sets of flexible bearings to improve test efficiency. The mechanical part of the test device consists of a double-headed motor, two pairs of flexible bearings, two pairs of wave generators with orthogonal long axes, two flexible cylinders of the same size and a semi-cylinder bracket, and the test part consists of two sound sensors, two temperature sensors, two vibration sensors and two tension sensors to measure the noise, temperature, vibration and friction of each pair of flexible bearings respectively.

[0005] Each pair of flexible bearings is embedded with a wave generator with the same structure and orthogonal long axes, and then pressed into the two ends of the inner hole of the flexible cylinder with equal diameter, and the orthogonal anti-symmetric deformation of the flexible cylinder is used to apply the same size and orthogonal follower load to each pair of flexible bearings. Two pairs of flexible bearings are installed at both ends of the motor shaft of the double-headed motor through the wave generator, so that four sets of flexible bearings can be installed in parallel under the same power source, and dynamic performance tests can be carried out simultaneously under the same working conditions.

[0006] The two flexible cylinder sections have no radial displacement during operation, and always maintain a circle with only a slight swing. Small holes are machined on the circumference of the flexible cylinder section, and multiple connecting screws with sharp steel needles or self-tapping threads at one end are inserted or screwed into the small holes on the circumference of the flexible cylinder section, while the other end of the connecting screw is fixed on the semi-cylindrical bracket. The pointed end of the connecting screw should transition through a conical outer circle or an arc outer circle at the contact point with the outer wall of the flexible cylinder to avoid the connecting screw constraining the swing deformation of the two sides of the flexible cylinder section.

[0007] The vibration sensor is fixed at the end of the connecting screw away from the flexible cylinder to achieve contact measurement of the vibration of each pair of flexible bearings. The sound sensor and temperature sensor are fixed through the bracket to measure the noise and temperature of each pair of flexible bearings in a non-contact manner. A sound insulation board with silencer cotton is installed between the two pairs of tested flexible bearings to reduce the interference of the sound signal measurement of the test bearings at both ends of the motor.

[0008] The tension sensor is fixed to the base, one end of the wire rope is connected to the tension sensor, and the other end is fixed to the outer circle of the middle section of the flexible cylinder. In the working state, due to the circularity of the middle section of the flexible cylinder, the wire rope is always tangent to the outer surface of the flexible cylinder. The friction torque of each pair of flexible bearings can be obtained by multiplying the value of the tension sensor by the outer diameter of the flexible cylinder.

[0009] Since the load of the double-head motor is only the gravity of the motor shaft and the friction torque of the flexible bearing, and each test, four sets of flexible bearings are tested simultaneously under the same working conditions, which can meet the needs of batch testing, the entire test device has the characteristics of simple and compact structure, low power and high efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a diagram of the vibration, noise and temperature testing device of the flexible bearing with parallel flexible cylinder deformation and dynamic loading;

[0011] Figure 2 It is a schematic diagram of the assembly of the flexible bearing and the flexible cylinder;

[0012] Figure 3 It is a schematic diagram of the connection between the screw rod and the flexible cylinder and the semi-cylindrical bracket;

[0013] Figure 4 This is a diagram of a parallel flexible cylinder deformation follower loading flexible bearing friction torque measurement device. DETAILED DESCRIPTION

[0014] In order to make the technical problems, technical solutions and beneficial effects to be solved by the utility model more clearly understood, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0015] In the following description, specific details such as specific internal procedures and techniques are provided for the purpose of illustration rather than limitation, so as to provide a thorough understanding of the embodiments of the present invention. However, it should be clear to those skilled in the art that the present invention may be implemented in other embodiments without these specific details. In other cases, detailed descriptions of well-known systems, devices, circuits, and methods are omitted to avoid obstructing the description of the present invention with unnecessary details.

[0016] Embodiment 1

[0017] like Figure 1 As shown, this embodiment provides a parallel flexible cylinder deformation follow-up loading flexible bearing vibration, noise, and temperature test device diagram of the utility model. For the convenience of display, the cover 13 is removed. The mechanical part of the test device is composed of a double-headed motor 2, two semi-cylindrical brackets 4, two flexible cylinders 5, two pairs of flexible bearings 6, and two pairs of wave generators 7 with long axes perpendicular to each other. The test part is composed of two temperature sensors 8, two sound sensors 9, and two vibration sensors 11, which respectively measure the noise, temperature, and vibration of each pair of flexible bearings 6.

[0018] like Figure 2As shown, each pair of flexible bearings 6 is embedded with a wave generator 7 of the same structure and with long axes perpendicular to each other, and then pressed into the two ends of the inner hole of the flexible cylinder 5 of equal diameter. Since the wave generator 6 is a non-circular elliptical shape and the long axes are perpendicular to each other, the flexible cylinder 5 is forced to undergo orthogonal antisymmetric deformation, and the orthogonal antisymmetric deformation of the flexible cylinder 5 is used to apply a follow-up load of the same size and orthogonal direction to each pair of flexible bearings 6. Two pairs of flexible bearings 6 are respectively installed on the motor shafts 3 at both ends of the double-headed motor 2 through the wave generator 7, so that four sets of flexible bearings 6 are installed in parallel under the same power source, and dynamic performance tests are carried out simultaneously under the same working conditions.

[0019] The cross sections of the two flexible cylinders 5 do not have radial displacement during operation, and always maintain a circle with only a slight swing. Small holes are machined on the circumference of the cross section of the flexible cylinder 5, and multiple connecting screws 10 with sharp steel needles 10A or self-tapping threads 10B at one end are connected. Figure 3 As shown, the connecting screw 10 is inserted or screwed into the small hole on the circumference of the middle section of the flexible cylinder 5, and the other end of the connecting screw 10 is fixed to the semi-cylindrical bracket 4 fixedly connected to the housing of the double-headed motor 2. The contact point between the pointed end of the connecting screw 10 and the outer wall of the flexible cylinder 5 should be transitioned through a conical outer circle or an arc outer circle to avoid the connecting screw 10 constraining the swing deformation of both sides of the middle section of the flexible cylinder 5.

[0020] like Figure 3 As shown in Figure (a), when one end of the connecting screw 10 is provided with a sharp steel needle 10A, the connecting screw 8 is directly connected and fixed to the semi-cylindrical bracket 4 through a thread. Figure 3 As shown in Figure (b), when one end of the connecting screw 10 has a self-tapping thread 10B, the connecting screw 10 is fixedly connected to the semi-cylindrical bracket 4 by two nuts 15.

[0021] The end of the connecting screw 10 away from the flexible cylinder 5 is provided with a small thread for fixing the vibration sensor 11 to achieve contact measurement of the vibration of each pair of flexible bearings 6. The temperature sensor 8 and the sound sensor 9 are fixed by the bracket to non-contactly measure the noise and temperature of each pair of flexible bearings 6. A sound insulation board 12 with sound-absorbing cotton is installed between the two pairs of tested flexible bearings to reduce the interference of the sound signal measurement of the test bearings at both ends of the double-headed motor 12.

[0022] Embodiment 2

[0023] like Figure 4As shown, this embodiment provides a parallel flexible cylinder deformation loading flexible bearing friction torque measuring device of the utility model. The difference from the first embodiment is that the semi-flexible cylinder bracket 4 and the vibration sensor 11 are removed, and two tension sensors 16 are added to measure the friction torque of each pair of flexible bearings 6. The tension sensor 16 is fixed to the bottom plate 1 and connected to the flexible cylinder 5 through the wire rope 15. Due to the circularity preservation feature of the cross section of the flexible cylinder 6, the wire rope 16 is always tangent to the outer surface of the flexible cylinder 5. According to the measurement value F of the tension sensor 16 multiplied by the lever arm l, the friction torque of each pair of flexible bearings 6 can be obtained.

[0024] In the first and second embodiments, different levels of load can be applied to the flexible bearing 6 by adjusting the wall thickness and length of the flexible cylinder 5. When using flexible cylinders 5 of different lengths, it is only necessary to change the length of the corresponding positioning sleeve 14. The entire device loads each pair of flexible bearings 6 through the deformation of the flexible cylinder 5 itself, without applying other external forces. The double-headed motor 2 only bears the gravity of the motor shaft 3 and the friction torque of the flexible bearing 6, and in each test, four sets of flexible bearings 6 are tested simultaneously under the same working conditions, which can meet the needs of batch testing. Therefore, the entire test device has the characteristics of simple structure, compactness, low power, and high efficiency.

[0025] The preferred specific embodiments of the utility model are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the utility model on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. A parallel flexible cylinder deformation and dynamic loading flexible bearing dynamic performance testing device, characterized in that: The mechanical part of the test device is composed of a double-head motor, two pairs of flexible bearings, two pairs of wave generators with long axes perpendicular to each other, two flexible cylinders of the same size and a semi-cylindrical bracket. The test part is composed of two sound sensors, two temperature sensors, two vibration sensors and two tension sensors to measure the noise, temperature, vibration and friction of each pair of flexible bearings respectively. Each pair of flexible bearings is embedded with a wave generator with the same structure and long axes perpendicular to each other, and then pressed into the two ends of the inner hole of a flexible cylinder with the same size and equal diameter. The orthogonal antisymmetric deformation of the flexible cylinder is used to apply a follow-up load of the same size and orthogonal direction to each pair of flexible bearings. The two pairs of tested flexible bearings are respectively installed on the motor shafts at both ends of the double-headed motor, so that four sets of flexible bearings can be installed in parallel under the same power source, and dynamic performance tests can be carried out simultaneously under the same working conditions.

2. The parallel flexible cylinder deformation and dynamic loading flexible bearing dynamic performance testing device according to claim 1 is characterized in that: The two flexible cylinder middle sections have no radial displacement during the working process and always maintain a circle with only a small swing. Small holes are processed on the circumference of the flexible cylinder middle section, and multiple connecting screws with sharp steel needles or self-tapping threads at one end are inserted or screwed into the small holes on the circumference of the flexible cylinder middle section, while the other end of the connecting screw is fixed on the semi-cylindrical bracket. The contact between the pointed end of the connecting screw and the outer wall of the flexible cylinder should be transitioned through a tapered outer circle or an arc outer circle to avoid the connecting screw constraining the swing deformation of the two sides of the flexible cylinder middle section.

3. The parallel flexible cylinder deformation and dynamic loading flexible bearing dynamic performance testing device according to claim 1 or 2, characterized in that: The vibration sensor is fixed on the connecting screw away from the end of the flexible cylinder to realize contact measurement of the vibration of each pair of flexible bearings; the sound sensor and temperature sensor are fixed by the bracket to measure the noise and temperature of each pair of flexible bearings non-contactly; a sound insulation board with silencer cotton is installed between the two pairs of tested flexible bearings to reduce the interference of the sound signal measurement of the test bearings at both ends.

4. The parallel flexible cylinder deformation and dynamic loading flexible bearing dynamic performance testing device according to claim 1 or 2, characterized in that: The tension sensor is fixed on the base, one end of the wire rope is connected to the tension sensor, and the other end is fixed on the outer circle of the middle section of the flexible cylinder. Under working conditions, due to the circularity-preserving characteristics of the middle section of the flexible cylinder, the wire rope is always tangent to the outer circle surface of the flexible cylinder. The friction torque of each pair of flexible bearings can be obtained by multiplying the force measured by the tension sensor by the force arm.

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