A method for controlling assembly precision of assembly parts

Abstract

The present invention discloses a method for controlling assembly precision of an assembly, comprising the following steps: analyzing the structural dimensions that need to be controlled during assembly of the assembly, determining the precision requirements of the key guaranteed dimensions; obtaining the error value of the key guaranteed dimensions according to the precision requirements of the key guaranteed dimensions and combining the actual measurement data of the key guaranteed dimensions; writing the error value of the key guaranteed dimensions into the compensation module of the numerical control system, and the numerical control system calling the instructions of the compensation module, correcting the processing code of the user, and completing the error compensation. The method for controlling assembly precision of an assembly can achieve error compensation of the key guaranteed dimensions by determining the precision requirements of the key guaranteed dimensions, comparing them with the actual data, and combining them with the numerical control system, so that the key dimensions of the parts processed by the machine tool can be guaranteed, so that the assembly precision meets the requirements.

Description

Technical Field

[0001] The invention relates to a method for controlling the assembly precision of an assembly part, and belongs to the technical field of research on machine tool processing precision control. Background Art

[0002] An assembly is composed of multiple parts, and its accuracy depends not only on the precision of the individual parts but also on the precision of the assembly. Different materials and manufacturing processes result in different tolerance ranges for each part. Improving the overall machining accuracy of each part can improve assembly quality, but this approach also increases costs. Furthermore, each part is machined and manufactured by a machine tool. As the machine tool ages, the clearances between components increase, reducing the assembly accuracy. A product typically consists of multiple components, and the accuracy of the assembly depends not only on the precision of each component but also on the precision of the assembly between them. Different materials have different tolerance ranges, and choosing matching parts with high mating surface precision ensures assembly accuracy.

[0003] It can be seen that in order to select matching parts with higher mating surface accuracy to ensure assembly accuracy, a method for controlling assembly accuracy of assemblies is urgently needed. Summary of the Invention

[0004] The purpose of the present invention is to overcome the deficiencies in the prior art and provide a method for controlling the assembly accuracy of an assembly. By determining the accuracy requirements of key guaranteed dimensions and comparing them with actual data, the error value of the key guaranteed dimensions is obtained. Combined with a numerical control system, the error compensation of the key guaranteed dimensions can be achieved, so that the key dimensions of the parts processed by the machine tool can be guaranteed, so that the assembly accuracy meets the requirements.

[0005] To achieve the above object, the present invention is implemented by adopting the following technical solutions:

[0006] In a first aspect, the present invention provides a method for controlling assembly precision of an assembly, comprising the following steps:

[0007] Analyze the structural dimensions that need to be controlled during assembly and determine the key dimensions to ensure accuracy;

[0008] According to the accuracy requirements of the key guaranteed dimensions and combined with the actual measurement data of the key guaranteed dimensions, the error value of the key guaranteed dimensions is obtained;

[0009] The error value of the key dimension is written into the compensation module of the CNC system. The CNC system calls the instructions of the compensation module, corrects the user's processing code, and completes the error compensation.

[0010] Furthermore, the key guarantee size includes at least one of the following:

[0011] Straightness;

[0012] angle.

[0013] Furthermore, the method for determining the dimensional accuracy requirement includes the following steps:

[0014] Determine the geometric data of non-assembly surfaces and combine geometric theorems to determine the ideal data for key guaranteed dimensions.

[0015] Furthermore, the method for obtaining the error value includes the following steps:

[0016] Use testing equipment to measure the actual data of key dimensions of the parts to be assembled;

[0017] The actual data obtained are compared with the ideal data to obtain the error value.

[0018] Furthermore, the geometric theorems include the law of cosines and the Pythagorean theorem.

[0019] In a second aspect, the present invention provides a device for controlling assembly precision of an assembly, comprising:

[0020] Precision determination module: used to analyze the structural dimensions that need to be controlled during assembly and determine the key dimensional accuracy requirements;

[0021] Error determination module: used to obtain the error value of the key guaranteed dimension based on the accuracy requirement of the key guaranteed dimension and the actual measurement data of the key guaranteed dimension;

[0022] Error compensation module: It is used to write the error value of the key dimension into the compensation module of the CNC system. The CNC system calls the instructions of the compensation module, corrects the user's processing code, and completes the error compensation.

[0023] In a third aspect, the present invention provides an assembly precision control device for an assembly, comprising a processor and a storage medium;

[0024] The storage medium is used to store instructions;

[0025] The processor is configured to operate according to the instructions to execute the steps of the method according to the first aspect.

[0026] In a fourth aspect, the present invention provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the method described in the first aspect.

[0027] Compared with the prior art, the present invention has the following beneficial effects:

[0028] The assembly precision control method provided by the present invention determines the precision requirements of the key guaranteed dimensions, compares them with actual data, obtains the error value of the key guaranteed dimensions, and combines it with the numerical control system to realize error compensation of the key guaranteed dimensions, so that the key dimensions of the parts processed by the machine tool can be guaranteed and the assembly precision meets the requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 is a flow chart of the assembly precision control method provided in Example 1;

[0030] Figure 2 Part assembly dimensions;

[0031] Figure 3 Description of key dimensional errors;

[0032] Figure 4 Parts assembly angle;

[0033] Figure 5 Key angle error description;

[0034] Figure 6 Error correction process for key dimensions. DETAILED DESCRIPTION

[0035] The technical solution of the present invention is described in detail below through the accompanying drawings and specific embodiments. It should be understood that the embodiments of the present application and the specific features in the embodiments are detailed descriptions of the technical solution of the present application, rather than limitations on the technical solution of the present application. Unless there is a conflict, the embodiments of the present application and the technical features in the embodiments can be combined with each other.

[0036] The term "and / or" in this document simply describes a relationship between related objects, indicating that three possible relationships exist. For example, "A and / or B" can mean: A exists alone, A and B exist simultaneously, or B exists alone. Additionally, the character " / " in this document generally indicates an "or" relationship between the related objects.

[0037] Example 1:

[0038] Figure 1 This is a flow chart of a method for controlling assembly precision of an assembly in accordance with the first embodiment of the present invention. The assembly precision control method provided in this embodiment can be applied to a terminal and can be executed by an assembly precision control device. The device can be implemented in software and / or hardware and can be integrated into a terminal, such as any smartphone, tablet computer, or computer device with communication capabilities. Figure 1 , the method of this implementation specifically includes the following steps:

[0039] Step A: Analyze the structural dimensions that need to be controlled during assembly and determine the key dimensional accuracy requirements;

[0040] Step B: Based on the accuracy requirements of the key guaranteed dimensions and the actual measurement data of the key guaranteed dimensions, the error value of the key guaranteed dimensions is obtained;

[0041] Step C: Write the error value of the key dimension into the compensation module of the CNC system. The CNC system calls the instructions of the compensation module, corrects the user's processing code, and completes the error compensation.

[0042] Step Aa: The key guarantee dimensions include at least one of the following:

[0043] Straightness;

[0044] angle.

[0045] Since the size adjustment of the assembly surface is completed by cutting, ensuring these two types of dimensions can generally ensure the overall assembly accuracy. If other special types of assembly dimensions need to be guaranteed, such as shape and position accuracy, they can be guaranteed by measuring the assembly plane, contour accuracy, positioning accuracy, etc.

[0046] Step Ab: The method for determining the key dimensional accuracy requirements includes the following steps:

[0047] Determine the geometric data of non-assembly surfaces and combine geometric theorems to determine the ideal data for key guaranteed dimensions.

[0048] Step Ba: The method for obtaining the error value comprises the following steps:

[0049] Use testing equipment to measure the actual data of key dimensions of the parts to be assembled;

[0050] The actual data obtained are compared with the ideal data to obtain the error value.

[0051] Step Bb: The geometric theorems include the law of cosines and the Pythagorean theorem;

[0052] Since the key dimension types guaranteed are straightness and angle, the geometric data of the non-assembly surface combined with the cosine theorem and the Pythagorean theorem can determine the accuracy requirements of the key dimensions.

[0053] In order to implement the above method, the present invention uses the matching size of the processing area as a straight line as an example, as shown in the attached figure. Figure 2 As shown. The key dimensions to be ensured here are The straightness and angles φ1 and φ2.

[0054]

[0055]

[0056] In the above formula (2), P 2x and P 5x are the coordinates of P2 and P5. The value of ∠P1P5P4 depends on the distance between P1 and P4.

[0057] Due to the existence of assembly clearance, Δφ1 is the angular error between the assembled parts, as shown in the attached Figure 3 To ensure easy assembly of components, there must be an assembly angle φ1-Δφ1 between the components. When this assembly angle exists, the new coordinates (x1, y1) of the cutting point P5 can be calculated as follows:

[0058]

[0059]

[0060] The coordinates (x, y) and angles (φ1-Δφ1) can be measured directly. After (x1, y1) are determined, the NC program is modified to ensure the key dimensions of the machined part, thereby matching the actual fitting dimensions of the measured assembly part.

[0061] In the same way, due to imperfect part processing, the angle φ3 deviates from the ideal position, such as Figure 4 In order to adjust the angle to the ideal position, the coordinate point P4 needs to be corrected, as shown in Figure 5 Adjust the angle (φ3+Δφ3) so that the assembled parts are in the ideal fit.

[0062] After determining the coordinate points P1, P5, and angles φ1 and φ3, adjust the coordinate points P2, P4. The specific method is to modify the G code used for processing so that P1, P5, φ1 and φ3 are in the ideal position.

[0063] When the expected position is P i , the error generated by predicting the expected position based on the position of the coordinate point that needs to be guaranteed is e(P i ), the error compensation position ΔP can be calculated, so the error compensation position ΔP is sent to the compensation module and converted into CNC code to realize error compensation.

[0064] ΔP=P i -e(P i ) (5)

[0065] P i represents the ideal tool position; ΔP represents the error compensation position calculated by the error compensation model; e(P i ) represents the error in the expected position.

[0066] The specific process of machine tool geometric error compensation is as follows: Figure 6 This method ensures the key dimensions of parts processed by machine tools and ensures that the assembly accuracy meets the requirements.

[0067] In summary, the assembly accuracy control method provided in this embodiment determines the accuracy requirements of the key guaranteed dimensions, compares them with the actual data, obtains the error value of the key guaranteed dimensions, and combines it with the numerical control system to achieve error compensation of the key guaranteed dimensions, so that the key dimensions of the parts processed by the machine tool can be guaranteed, so that the assembly accuracy meets the requirements.

[0068] Example 2:

[0069] This embodiment also provides a device for controlling assembly precision of an assembly, comprising:

[0070] Precision determination module: used to analyze the structural dimensions that need to be controlled during assembly and determine the key dimensional accuracy requirements;

[0071] Error determination module: used to obtain the error value of the key guaranteed dimension based on the accuracy requirement of the key guaranteed dimension and the actual measurement data of the key guaranteed dimension;

[0072] Error compensation module: It is used to write the error value of the key dimension into the compensation module of the CNC system. The CNC system calls the instructions of the compensation module, corrects the user's processing code, and completes the error compensation.

[0073] The assembly precision control device provided by the embodiment of the present invention can execute the assembly precision control method provided by any embodiment of the present invention, and has the corresponding functional modules and beneficial effects of the execution method.

[0074] Example 3:

[0075] An embodiment of the present invention further provides an assembly precision control device, comprising a processor and a storage medium;

[0076] The storage medium is used to store instructions;

[0077] The processor is configured to operate according to the instructions to execute the steps of the following method:

[0078] Analyze the structural dimensions that need to be controlled during assembly and determine the key dimensions to ensure accuracy;

[0079] According to the accuracy requirements of the key guaranteed dimensions and combined with the actual measurement data of the key guaranteed dimensions, the error value of the key guaranteed dimensions is obtained;

[0080] The error value of the key dimension is written into the compensation module of the CNC system. The CNC system calls the instructions of the compensation module, corrects the user's processing code, and completes the error compensation.

[0081] Example 4:

[0082] An embodiment of the present invention further provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, implements the steps of the following method:

[0083] Analyze the structural dimensions that need to be controlled during assembly and determine the key dimensions to ensure accuracy;

[0084] According to the accuracy requirements of the key guaranteed dimensions and combined with the actual measurement data of the key guaranteed dimensions, the error value of the key guaranteed dimensions is obtained;

[0085] The error value of the key dimension is written into the compensation module of the CNC system. The CNC system calls the instructions of the compensation module, corrects the user's processing code, and completes the error compensation.

[0086] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0087] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the steps in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0088] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1The function specified in one or more boxes.

[0089] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0090] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for controlling assembly accuracy of an assembly, characterized in that: The method comprises the following steps: Analyze the structural dimensions that need to be controlled during assembly, and determine the key dimensions to ensure accuracy; According to the accuracy requirements of the key guaranteed dimensions and the actual measurement data of the key guaranteed dimensions, the error values ​​of the key guaranteed dimensions are obtained; Write the error value of the key guaranteed dimension into the compensation module of the CNC system. The CNC system calls the instructions of the compensation module, corrects the user's processing code, and completes the error compensation. The method for determining the dimensional accuracy requirement includes the following steps: Determine the geometric data of non-assembly surfaces, and use geometric theorems to determine the ideal data for key dimensions.

2. The assembly precision control method according to claim 1, characterized in that: The key guarantee dimensions include at least one of the following: Straightness; angle.

3. The assembly precision control method of claim 1, characterized in that: The method for obtaining the error value comprises the following steps: Use testing equipment to measure the actual data of key dimensions of the parts to be assembled; The actual data obtained are compared with the ideal data to obtain the error value.

4. The assembly precision control method of claim 1, characterized in that: The geometric theorems include the law of cosines and the Pythagorean theorem.

5. A device for controlling assembly precision, characterized in that: The device comprises: Precision determination module: used to analyze the structural dimensions that need to be controlled during assembly and determine the precision requirements of the key dimensions; Error determination module: used to obtain the error value of the key guaranteed dimension according to the accuracy requirement of the key guaranteed dimension and the actual measurement data of the key guaranteed dimension; Error compensation module: used to write the error value of the key guaranteed dimension into the compensation module of the CNC system. The CNC system calls the instructions of the compensation module to correct the user's processing code and complete the error compensation; The method for determining the dimensional accuracy requirement includes the following steps: Determine the geometric data of non-assembly surfaces, and use geometric theorems to determine the ideal data for key dimensions.

6. A device for controlling assembly precision, characterized in that: including processor and storage medium; The storage medium is used to store instructions; The processor is used to operate according to the instructions to execute the steps of the method according to any one of claims 1 to 4.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps of the method described in any one of claims 1 to 4 are implemented.

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