High-precision bearing automatic assembly control system and method

Abstract

This invention discloses a high-precision bearing automatic assembly control method and system. The method includes: acquiring part parameters and converting them into digitized feature vectors; performing pairing and screening using a matching calculation model; assembling the parts into an intermediate body, pre-calculating the preset volume of the closed cavity based on the feature vectors, and quantitatively injecting grease; pressing in a sealing ring to form a bearing assembly, driving it to rotate around its central axis and supplementing it with axial vibration, using a centrifugal force field to drive the lubricating medium distribution to homogenize, eliminating measurement interference caused by uneven distribution; acquiring measured clearance values ​​with elastic deformation compensation, and dynamically correcting the subsequent batch matching model based on the deviation between the measured value and the target value. This invention eliminates the physical interference of the lubricating medium on the measurement, achieves closed-loop error compensation, and significantly improves the assembly quality stability of high-precision bearings.

Description

Technical Field

[0001] This invention relates to the field of bearing processing and automated assembly technology, specifically to a high-precision automatic bearing assembly control system and method. Background Technology

[0002] As a core component of mechanical equipment, the assembly quality of bearings directly affects the operational accuracy and service life of rotating machinery. During bearing assembly, the accuracy of residual clearance control is a key indicator of assembly quality. Traditional assembly systems typically rely solely on simple pairing based on the static geometric dimensions of parts, which is insufficient to offset the cumulative assembly errors generated during actual assembly.

[0003] Furthermore, to ensure bearing lubrication performance, the assembly process typically includes filling the bearing with a lubricating medium. However, the distribution of the lubricating medium within the bearing's internal cavity is random. During subsequent online clearance acquisition, this unevenly distributed lubricating medium generates significant nonlinear viscous resistance. This measurement interference caused by the uneven distribution of the lubricating medium can lead the system to misinterpret the grease's displacement force as mechanical resistance or interference fit within the bearing. Consequently, the acquired measured clearance value fails to accurately reflect the bearing's physical clearance state, severely impacting the reliability of assembly error compensation. Summary of the Invention

[0004] The technical problem to be solved by the present invention is to provide a high-precision automatic bearing assembly control system and method, which aims to solve the measurement interference problem caused by uneven distribution of lubricating medium in the existing bearing assembly process, and overcome the defect of insufficient clearance control accuracy caused by the lack of an effective error pre-compensation mechanism.

[0005] The high-precision bearing automatic assembly control method provided by this invention includes: S1. Obtain the geometric shape and position parameters of several bearing parts to be assembled, and convert them into digital feature vectors. S2. Using the selection calculation model, pairing and screening are performed based on each of the feature vectors to select a set of bearing parts from the plurality of bearing parts, which consists of the bearing inner ring, bearing outer ring, rolling elements, cage and seal ring, and can achieve tolerance complementarity and the expected residual clearance after tolerance complementarity meets the preset target value. S3. Assemble the bearing inner ring, bearing outer ring, cage and rolling elements of the set of bearing parts according to the bearing structure to form an assembly intermediate with an open internal cavity; based on the characteristic vectors of each of the set of bearing parts, calculate in advance the preset volume of the closed internal cavity of the bearing assembly formed after the assembly intermediate is sealed by the sealing ring, and inject a predetermined amount of lubricating medium into the open internal cavity of the assembly intermediate according to the preset volume. S4. After injecting the lubricating medium into the open internal cavity of the assembly intermediate, press the sealing ring of the set of bearing parts into the assembly intermediate to seal the open internal cavity of the assembly intermediate, forming the bearing assembly with a closed internal cavity. S5. Drive the bearing assembly to rotate around its central axis, and use the centrifugal force field to drive the lubricating medium to be evenly distributed in the closed internal cavity, so as to eliminate the measurement interference caused by the uneven distribution of the lubricating medium in the closed internal cavity to the clearance acquisition process of the bearing assembly. S6. Collect the measured clearance value of the bearing assembly; S7. Obtain the deviation between the measured clearance value and the preset target value, and dynamically correct the matching calculation model when subsequent batches of bearing parts are executed in step S2 based on the deviation.

[0006] Preferably, step S1 further includes: The surface morphology features of the bearing parts are obtained, and the shape error is extracted from them. The shape error includes at least one of the roundness deviation and waviness deviation of the bearing inner ring groove, the bearing outer ring groove and the rolling element surface. The geometric shape and position parameters of the bearing part are compensated using the shape error to generate the feature vector.

[0007] Preferably, step S3 further includes: When the lubricating medium is injected into the open internal cavity of the assembly intermediate, the assembly intermediate is driven to rotate around its central axis at a first rotation speed, so that the lubricating medium is circumferentially distributed in the open internal cavity of the assembly intermediate. Wherein, the first rotational speed is lower than the rotational speed at which the bearing assembly is rotated in step S5.

[0008] Preferably, step S5, driving the bearing assembly to rotate, specifically includes: The bearing assembly is driven to perform a compound rotational motion including an acceleration phase, a constant speed phase, and a braking phase; The alternating inertial force generated by the switching of motion states breaks up the initial accumulation clusters of the lubricating medium in the closed internal cavity of the bearing assembly.

[0009] Preferably, step S5 further includes: While rotating the bearing assembly, axial vibration is applied to the bearing assembly to utilize the coupling effect of the centrifugal force field and the vibration field to drive the lubricating medium to generate axial overflow along the inner wall groove of the outer ring of the bearing, thereby filling the area in the closed internal cavity of the bearing assembly that is blocked by the cage and the rolling elements.

[0010] Preferably, step S6 further includes: A predetermined axial load is applied to the bearing assembly to obtain the displacement of the bearing assembly under stress. The axial elastic deformation compensation value of the bearing assembly is calculated based on the displacement and the predetermined axial load, and used as a correction variable for the measured clearance value.

[0011] Preferably, step S7 further includes: Analyze the trend data consisting of the deviations of each bearing assembly in the historical output sequence; Based on this, trend compensation is performed on the pairing screening of the bearing parts in subsequent batches during step S2.

[0012] The present invention also discloses a high-precision bearing automatic assembly control system, a memory and a processor, wherein the memory stores a computer program, and the computer program is executed by the processor to implement the method described in any one of the above.

[0013] One or more technical solutions provided in this invention have at least the following technical effects or advantages: This invention transforms the geometric and positional parameters of the bearing parts to be assembled into digital feature vectors, enabling selection calculations based on a deeper data dimension. This digital representation method can select the optimal part combination from the perspective of tolerance complementarity and ensure that the expected residual clearance meets the preset target value, thus guaranteeing assembly accuracy from the source. Furthermore, this invention injects grease based on the pre-calculated preset volume of the closed internal cavity of the bearing assembly and drives the bearing assembly to rotate around its central axis. It cleverly utilizes centrifugal force to drive the lubricating medium to be evenly distributed within the closed internal cavity of the bearing assembly. This step effectively eliminates measurement interference caused by uneven lubricating medium distribution during clearance acquisition, providing a reliable physical prerequisite for subsequent accurate online acquisition of clearance values.

[0014] Moreover, by comparing the measured clearance value with the preset target value, the present invention can obtain the accurate deviation in real time. This deviation is used to dynamically correct the matching calculation model when subsequent batches of bearing parts are matched and screened. Through this pre-compensation control mechanism, the present invention can effectively offset the assembly error generated by the bearing parts during the assembly process, and significantly improve the consistency of bearing clearance and assembly accuracy in a mass production environment. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the structure of the assembly intermediate before grease injection in an embodiment of the present invention.

[0016] Figure 2 This is a schematic diagram of the process state in which the grease injection mechanism injects lubricating medium into the assembly intermediate in an embodiment of the present invention.

[0017] Figure 3 This is a schematic diagram of the bearing assembly performing a homogenization process under the coupled action of rotation and vibration in an embodiment of the present invention.

[0018] Explanation of reference numerals in the attached drawings: 10, bearing inner ring; 20, bearing outer ring; 30, rolling element; 40, cage; 50, seal ring; 61, open internal cavity; 62, closed internal cavity; 70, grease injection mechanism; 80, lubricating medium; 90, vibration generator; 100, assembly intermediate; 200, bearing assembly. Detailed Implementation

[0019] To make the objectives and technical solutions of this invention clearer, the high-precision bearing automatic assembly control method of this invention will be described in detail below with reference to the accompanying drawings and embodiments.

[0020] The present invention first performs step S1 to obtain the geometric shape and position parameters of several bearing parts to be assembled and convert them into digital feature vectors. In actual execution, the several bearing parts include the bearing inner ring 10, bearing outer ring 20, rolling elements 30, cage 40, and sealing ring 50 that constitute the bearing entity. The system uses a measuring device to obtain the surface morphology features of the bearing parts and extracts shape errors from them. The shape errors include, but are not limited to, at least one of the roundness deviation and waviness deviation of the bearing inner ring groove, bearing outer ring groove, and rolling element surface. In order to make the subsequent calculations closer to the physical reality, the system uses these extracted shape errors to compensate for the geometric shape and position parameters of the bearing parts, thereby generating digital feature vectors. This deep modeling method can significantly reduce the assembly stress prediction error caused by microscopic shape irregularities.

[0021] Step S2 involves using a matching calculation model to perform pairing screening based on the aforementioned feature vectors. This process aims to select a set of bearing components, consisting of the inner bearing ring 10, outer bearing ring 20, rolling elements 30, cage 40, and seal ring 50, that achieves complementary tolerances and whose expected residual clearance meets a preset target value. Alternatively, the matching calculation model can employ a genetic algorithm, neural network, or linear regression model for multi-criteria optimization.

[0022] In step S3, the selected bearing inner ring 10, bearing outer ring 20, cage 40, and rolling elements 30 are first assembled according to the bearing structure to form an assembly intermediate 100 with an open internal cavity 61, as shown in the attached figure. Figure 1 As shown. Based on the digital feature vectors of the bearing components, the system pre-calculates the preset volume of the subsequently formed closed internal cavity 62 using geometric modeling methods, and accordingly, the grease injection mechanism 70 injects a predetermined amount of lubricating medium 80 into the open internal cavity 61, as shown in the attached figure. Figure 2 As shown.

[0023] To achieve the desired homogenization effect, the grease injection nozzle of the grease injection mechanism 70 is precisely aligned with the annular gap between the flange of the inner ring 10 and the inner diameter of the cage 40 for grease injection, allowing the lubricating medium 80 to first adhere to and wet the side of the inner ring. During the injection process, the system drives the assembly intermediate 100 to rotate around its central axis at a first rotational speed, typically set between 100 and 500 rpm, preferably 200 rpm. This ensures the lubricating medium 80 is circumferentially distributed, preventing severe single-point accumulation during static grease injection, and utilizes a weak centrifugal force to overcome the initial shear stress of the medium, causing it to spread out circumferentially and form a continuous annular strip.

[0024] In step S4, the sealing ring 50 is pressed into the assembly intermediate 100 to form a bearing assembly 200 with a closed internal cavity 62, as shown in the attached figure. Figure 3 As shown. At this time, the lubricating medium 80 is often in an initial agglomerated state. If clearance is directly measured, the displacing force generated by the grease will produce significant nonlinear viscous resistance. This measurement interference will cause the system to misjudge the displacing force of the grease as mechanical resistance or interference fit inside the bearing, causing the measured clearance value to deviate from the physical reality.

[0025] Therefore, in step S5 of this invention, the drive bearing assembly 200 is rotated at high speed around its central axis. The rotational speed at this time is much higher than the first speed, typically set between 1000 and 6000 rpm. The system drives the bearing to perform a compound rotational motion including an acceleration phase, a constant speed phase, and a braking phase, using the alternating inertial force generated by the sudden acceleration to tear apart the initial grease buildup.

[0026] While rotating, axial vibration is applied by vibration generator 90. The high-frequency axial vibration applied by vibration generator 90 gives the lubricating medium 80 axial power, which couples with the radial centrifugal force generated by high-speed rotation, driving the lubricating medium 80 to obtain a composite motion vector obliquely outward. This coupling effect induces the lubricating medium 80 to generate significant axial overflow along the inner wall groove of the bearing outer ring 20, thereby giving it "diffusing" ability, enabling it to smoothly overcome the physical barriers of cage 40 and rolling elements 30, and forcibly fill the dry dead corners and non-contact areas that were originally formed due to geometric obstruction.

[0027] Simultaneously, the rolling element 30 continuously rotates and revolves between the inner and outer rings. Its surface acts like an applicator, constantly grabbing the lubricant from the grease layer of the outer ring 20 and compacting it onto the groove surface of the inner ring 10. Ultimately, under the combined action of centrifugal force, axial vibration, and mechanical coating, the lubricating medium 80 is evenly spread across the entire inner wall surface of the outer ring 20, the outer groove surface of the inner ring 10, and all the walls within the enclosed internal cavity 62, forming a stable oil film with full surface coverage, uniform thickness, and no air bubbles.

[0028] Step S6 involves acquiring the measured clearance value of the bearing assembly 200. To obtain the true physical clearance, this embodiment applies a predetermined axial load (e.g., 5~15N) to the bearing assembly 200 and obtains the displacement under stress. Subsequently, the system calculates the axial elastic deformation compensation value of the bearing assembly based on the mapping relationship between the displacement and the load. And use it as a correction variable to correct the measurement results in real time, i.e., the true geometric clearance. This mechanism eliminates the influence of microscopic deformation of metal parts under stress on the clearance value.

[0029] Finally, step S7 is executed to obtain the deviation between the measured clearance value and the preset target value. This deviation is used to dynamically correct the matching calculation model when subsequent batches of bearing parts are paired and screened in real time. By analyzing the deviation trend of each bearing assembly in the historical output sequence, the system can identify systematic drifts caused by factors such as equipment wear and environmental fluctuations, and accordingly perform trend compensation for the pairing and screening of subsequent batches. This feedback control logic enables the matching model to have adaptive evolution capabilities, significantly improving clearance consistency in large-scale automated assembly environments.

[0030] The present invention also discloses a control system for implementing the above method, comprising a memory and a processor, wherein the memory stores an executable computer program. The processor executes the program to coordinate and schedule the measuring mechanism, the grease injection mechanism, the rotary drive mechanism, and the vibration generator, thereby realizing fully automated precision assembly control logic.

[0031] The above embodiments are merely preferred embodiments of the present invention. Any equivalent substitutions or improvements made by those skilled in the art to the grease injection parameters, rotation logic, or feedback model within the scope of the present invention should be included within the protection scope of the present invention.

Claims

1. A high-precision automatic bearing assembly control method, characterized in that, include: S1. Obtain the geometric shape and position parameters of several bearing parts to be assembled, and convert them into digital feature vectors. S2. Using the selection calculation model, pairing and screening are performed based on each of the feature vectors to select a set of bearing parts from the plurality of bearing parts, which consists of the bearing inner ring, bearing outer ring, rolling elements, cage and seal ring, and can achieve tolerance complementarity and the expected residual clearance after tolerance complementarity meets the preset target value. S3. Assemble the bearing inner ring, bearing outer ring, cage and rolling elements of the set of bearing parts according to the bearing structure to form an assembly intermediate with an open internal cavity; based on the characteristic vectors of each of the set of bearing parts, calculate in advance the preset volume of the closed internal cavity of the bearing assembly formed after the assembly intermediate is sealed by the sealing ring, and inject a predetermined amount of lubricating medium into the open internal cavity of the assembly intermediate according to the preset volume. S4. After injecting the lubricating medium into the open internal cavity of the assembly intermediate, press the sealing ring of the set of bearing parts into the assembly intermediate to seal the open internal cavity of the assembly intermediate, forming the bearing assembly with a closed internal cavity. S5. Drive the bearing assembly to rotate around its central axis, and use the centrifugal force field to drive the lubricating medium to be evenly distributed in the closed internal cavity, so as to eliminate the measurement interference caused by the uneven distribution of the lubricating medium in the closed internal cavity to the clearance acquisition process of the bearing assembly. S6. Collect the measured clearance value of the bearing assembly; S7. Obtain the deviation between the measured clearance value and the preset target value, and dynamically correct the matching calculation model when subsequent batches of bearing parts are executed in step S2 based on the deviation.

2. The method according to claim 1, characterized in that, Step S1 further includes: The surface morphology features of the bearing parts are obtained, and the shape error is extracted from them. The shape error includes at least one of the roundness deviation and waviness deviation of the bearing inner ring groove, the bearing outer ring groove and the rolling element surface. The geometric shape and position parameters of the bearing part are compensated using the shape error to generate the feature vector.

3. The method according to claim 1, characterized in that, Step S3 further includes: When the lubricating medium is injected into the open internal cavity of the assembly intermediate, the assembly intermediate is driven to rotate around its central axis at a first rotation speed, so that the lubricating medium is circumferentially distributed in the open internal cavity of the assembly intermediate. Wherein, the first rotational speed is lower than the rotational speed at which the bearing assembly is rotated in step S5.

4. The method according to claim 1, characterized in that, In step S5, driving the bearing assembly to rotate specifically includes: The bearing assembly is driven to perform a compound rotational motion including an acceleration phase, a constant speed phase, and a braking phase; The alternating inertial force generated by the switching of motion states breaks up the initial accumulation clusters of the lubricating medium in the closed internal cavity of the bearing assembly.

5. The method according to claim 1, characterized in that, Step S5 further includes: While rotating the bearing assembly, axial vibration is applied to the bearing assembly to utilize the coupling effect of the centrifugal force field and the vibration field to drive the lubricating medium to generate axial overflow along the inner wall groove of the outer ring of the bearing, thereby filling the area in the closed internal cavity of the bearing assembly that is blocked by the cage and the rolling elements.

6. The method according to claim 1, characterized in that, Step S6 further includes: A predetermined axial load is applied to the bearing assembly to obtain the displacement of the bearing assembly under stress. The axial elastic deformation compensation value of the bearing assembly is calculated based on the displacement and the predetermined axial load, and used as a correction variable for the measured clearance value.

7. The method according to claim 1, characterized in that, Step S7 further includes: Analyze the trend data consisting of the deviations of each bearing assembly in the historical output sequence; Based on this, trend compensation is performed on the pairing screening of the bearing parts in subsequent batches during step S2.

8. A high-precision bearing automatic assembly control system, comprising a memory and a processor, wherein the memory stores a computer program, and the computer program, when executed by the processor, implements the method as described in any one of claims 1 to 7.

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