A method for determining process holes of part connection holes in an assembly

Abstract

A method for determining a process hole for a part connection hole in an assembly, wherein the method is based on a known theoretical model of an assembly of at least two connected parts, and a three-dimensional process tolerance simulation analysis model is established by processing the assembly theoretical model. In the simulation analysis model, the part where the connection hole to be analyzed is located is used as a reference, an assembly relationship is established, tolerances are defined, and a measurement relationship is established, and the hole center offset or the maximum interference between holes is obtained. The maximum process aperture of the connection hole on the part is then converted through the hole center offset or the maximum interference between holes. Finally, the process hole of the connection hole is manufactured in the part prefabrication stage according to the maximum process aperture.

Description

Technical Field

[0001] The present application relates to aircraft manufacturing assembly technology, and in particular to a method for determining process holes of part connection holes in an assembly. Background Art

[0002] Modern aircraft models are characterized by large size, complex structure, and extensive use of composite materials and difficult-to-process materials. The fuselage structure is relatively complex and can be divided into many independent assemblies. Each independent assembly contains several parts, and there are contact and matching constraints between the assemblies. The assemblies are generally connected by holes, which are collectively referred to as connection holes. For example, in order to ensure the performance requirements of the fuselage assembly docking area, a large-sized connection hole structure is designed in the docking area. This type of structure has the characteristics of large hole size, high hole accuracy requirements, connection holes on different parts, many parts, large part thickness, and high part material hardness. In addition, the coordination relationship of the docking structure assembly is complex. In order to meet the coordination of the docking process and ensure the appearance quality requirements of the fuselage component docking area, the connection hole position and hole accuracy requirements are extremely high.

[0003] For assemblies similar to those described above, the connection holes in the docking area are usually coordinated by standard workers. After the assembly of each independent assembly is completed, the final hole state of the connection holes is completed by tooling to meet the final docking assembly requirements. The specific process method is: in the part prefabrication stage, the connection holes on the parts are not in the final hole state and are made into process holes. The assembly workshop proposes the process state requirements of the part connection holes to the parts workshop, and the parts workshop makes the process holes according to the process state requirements. After the parts are delivered to the assembly workshop, the assembly workshop positions and assembles the parts to form an assembly, and then uses tooling to complete the final hole state of the connection holes. This process method aims to ensure the position accuracy of the docking final hole, and relies on tooling to supplement the process hole state of the formed assembly connection hole to eliminate the position deviation of the connection hole during the part manufacturing and assembly process.

[0004] The biggest problem with this method is that the process holes of the connection holes are calculated by the engineering technicians in the assembly workshop based on engineering experience and simple coordination. Based on the coordination requirements of the final connection assembly, the process state of the connection hole diameter is relatively conservative, resulting in a smaller process hole diameter made during the prefabrication stage of the parts, and it is impossible to determine the maximum process hole diameter of the connection hole. This results in a large number of supplementary processing procedures for such connection holes during the assembly stage. However, when making large-sized holes for materials with high hardness and thickness, especially for complex assemblies where dedicated hole processing equipment cannot be used and the hole supplementary processing space is limited, it is very easy for the connection hole quality to exceed the tolerance level, and it takes a lot of time and energy for the operator, which makes the operator easily fatigued and causes other quality and safety accidents.

[0005] Therefore, it is necessary to provide engineering technicians with a method for determining the process holes of part connection holes in an assembly, accurately and quantitatively determine the maximum process hole diameter of the difficult-to-process part connection holes in a complex assembly, and avoid a large amount of reprocessing work after the parts are assembled to form an assembly. Take full advantage of the high hole making quality in the part prefabrication stage to maximize the size of the process hole diameter in the part prefabrication stage, thereby reducing the amount of reprocessing work after the parts are assembled, saving tool and measuring consumables, shortening the assembly cycle, and effectively improving the product hole making quality. Summary of the invention

[0006] The purpose of this application is to provide a method for determining the process hole of the part connection hole in the assembly, which is used to accurately and quantitatively determine the maximum process hole diameter of the difficult-to-process parts in the complex assembly during the part prefabrication stage during the aircraft body assembly process, so as to achieve balanced production, reasonable division of labor, save manpower, material resources, and financial resources, improve assembly quality, and shorten assembly cycle.

[0007] In order to achieve the above objectives, this application adopts the following technical solutions:

[0008] A method for determining a process hole of a part connection hole in an assembly, wherein a theoretical model of the assembly is known, the assembly comprises at least two or more butted parts, the parts are provided with connection holes, and the connection holes are made into process holes when the parts are not assembled, the aperture of the process holes is smaller than the theoretical aperture of the connection holes, and the aperture of the process holes is as close as possible to the theoretical aperture of the connection holes, and the method is characterized in that it comprises the following contents: 1) generating an analysis digital model of the assembly according to the theoretical model of the assembly, the analysis digital model comprising the matching constraint relationship of the butted parts; 2) simplifying and lightweighting the analysis digital model, and establishing a three-dimensional process tolerance simulation analysis model; 3) in the simulation analysis model, taking the part where the connection hole is located as a reference, sorting out the contact constraints on the part. 4) in the simulation analysis model, tolerances are defined for the contact constraints and fit constraints of all parts in the assembly relationship; 5) in the simulation analysis model, a measurement relationship for the connecting hole on the part is established, and the measurement relationship is used to measure the hole center offset of the connecting hole or the hole-to-hole interference between the connecting hole and the connecting hole of the docking part; 6) the above simulation analysis model is run to simulate the assembly and obtain the hole center offset of the connecting hole or the maximum hole-to-hole interference; 7) the maximum process aperture of the connecting hole on the part is calculated based on the hole center offset or the maximum hole-to-hole interference; 8) the process hole of the connecting hole is made in the part prefabrication stage based on the maximum process aperture.

[0009] The method for determining the process hole of the part connecting hole in the assembly is characterized in that, in step 7), the maximum diameter process hole of the connecting hole is obtained by using the aperture compensation hole center offset or the hole-hole interference, and the process hole is inscribed in the theoretical hole of the connecting hole in the assembly theoretical model.

[0010] The method for determining the process holes of part connection holes in an assembly is characterized in that, in step 7), if the number of connection holes on a part in the assembly is less than 10, the maximum process aperture of the connection holes on the part is calculated by using the maximum interference between holes.

[0011] The method for determining the process holes of the part connecting holes in the assembly is characterized in that, in step 5), when establishing the measurement relationship of the connecting holes on the parts, if there is no corresponding part connecting hole on the connecting hole on the assembly part to be analyzed in the simulation analysis model, then the theoretical position of the connecting hole on the assembly part to be analyzed is used as a reference to establish the measurement relationship between the connecting hole on the assembly part and the connecting hole at the theoretical position.

[0012] The method for determining the process holes of the part connection holes in the assembly is characterized in that, in step 7), when converting according to the hole center offset or the maximum interference between holes, the part connection hole that is docked with the part where the connection hole to be analyzed is located is used as a reference, and the docking part connection hole is assumed to be in the theoretical position of the assembly model.

[0013] Compared with the prior art, the advantages of the present application are: the maximum process aperture of the connection holes of the parts in the assembly can be accurately and quantitatively determined by this method, so that the process holes of the connection holes can be made in the part prefabrication stage. This method avoids the problem that the state of the process holes of traditional parts is conservative and cannot be accurately quantified. The method can give full play to the advantages of high precision and excellent quality of part hole making in the part prefabrication stage, greatly reduce the supplementary processing work of the connection holes of difficult-to-process parts in the assembly stage, save manpower, material resources and financial resources, improve the precision of hole making of difficult-to-process parts in complex assemblies, and shorten the assembly cycle of assemblies. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic diagram of the docking relationship of parts in an assembly.

[0015] Figure 2 Schematic diagram of the offset δ when measuring the center offset of the connecting hole.

[0016] Figure 3 The schematic diagram of the maximum process hole is calculated based on the hole center offset.

[0017] Figure 4 Schematic diagram of the maximum interference ε when measuring the interference between holes.

[0018] Figure 5 Schematic diagram of the circle corresponding to the maximum process hole diameter when measuring the interference between holes.

[0019] Explanation of numbers in the figure: 1 first docking part, 2 second docking part, 3 connecting hole, 4 first connecting hole, 5 center point of first connecting hole, 6 second connecting hole, 7 center point of second connecting hole, 8 hole center offset, 9 maximum process hole, 10 maximum interference between holes, 11 maximum process hole radius. DETAILED DESCRIPTION

[0020] Referring to the accompanying drawings, the process hole determination method of the part connection hole in the assembly of the present application is based on the theoretical model of the assembly, and the assembly includes at least two or more docking parts, such as Figure 1 The first docking part 1 and the second docking part 2 are provided with connection holes 3 respectively on the two docking parts. In order to make the connection hole 3 into a suitable process hole when the parts are not assembled, the aperture of the process hole should be smaller than the theoretical aperture of the connection hole 3, and the aperture of the process hole should be as close as possible to the theoretical aperture of the connection hole 3.

[0021] The specific method for determining the aperture of the process hole is as follows:

[0022] 1) Generate an analysis digital model of the assembly based on the theoretical model of the assembly, which includes the matching constraint relationship of the docking parts.

[0023] 2) Simplify and lighten the analysis digital model and establish a three-dimensional process tolerance simulation analysis model.

[0024] 3) In the simulation analysis model, with the part where the connection hole is located as a reference, sort out all the parts that have contact constraints and fit constraints on the part, and create an assembly relationship; during the creation process, strictly create an assembly relationship for each sorted part in accordance with the actual assembly process method of the parts. The more comprehensive and accurate the assembly relationship creation is, the more accurate the measurement result will be.

[0025] 4) In the simulation analysis model, tolerances are defined for the contact constraints and fit constraints of all parts in the assembly relationship.

[0026] 5) In the simulation analysis model, such as Figure 2As shown, a measurement relationship for the connection holes on the parts is established, and the measurement relationship is used to measure the relationship between the first connection hole 4 and the second connection hole 6 on the first docking part 1, including the hole center offset 8 between the center point 5 of the first connection hole and the center point 7 of the second connection hole or the maximum interference 9 between the holes. When establishing the measurement relationship for the connection holes on the parts, if there is no corresponding part connection hole for the connection hole on the assembly part to be analyzed in the simulation analysis model, the theoretical position of the connection hole on the assembly part to be analyzed is used as a reference to establish the measurement relationship between the connection hole on the assembly part and the connection hole at the theoretical position.

[0027] 6) Run the above simulation analysis model to simulate the assembly and obtain the hole center offset 8 of the connecting hole or the maximum interference 10 between the holes.

[0028] 7) If Figure 2 As shown in the figure, the maximum process aperture 9 of the connecting hole on the part is obtained by converting the hole center offset 8 or the maximum interference between holes. The hole center offset 8 is measured to obtain the offset between the center point 5 of the first connecting hole and the center point 7 of the second connecting hole. Using the principle of hole diameter compensation hole position deviation, we can get Figure 3 The maximum process hole 9 shown is unique and inscribed in the first connecting hole 4. If the hole radius is too small, the corresponding hole still has a margin. If the hole radius is too large, the corresponding hole will interfere. Figure 3 shown.

[0029] The non-overlapping portion of the first connecting hole 4 and the second connecting hole 6 is the interference portion between the holes, and the maximum interference amount 10 between the holes can be obtained, such as Figure 4 As shown, using the principle of aperture compensation hole position deviation, we can get Figure 5 The maximum process hole 9 shown is unique and inscribed in the first connecting hole 4. If the hole radius is too small, the corresponding hole still has a margin, and if the hole radius is too large, interference occurs in the corresponding hole.

[0030] In specific implementation, if the number of connecting holes on a part in an assembly is less than 10, the maximum process aperture of the connecting holes on the part is calculated by using the maximum interference between holes.

[0031] When converting according to the hole center offset or the maximum interference between holes, the connection hole of the part that is docked with the part where the connection hole to be analyzed is located is used as a reference. By default, the connection hole of the docking part is in the theoretical position of the assembly model.

[0032] 8) Finally, the engineering technicians determine the maximum process hole 9 according to the maximum process hole radius 11 and the actual cutting plan, and the operators make the process holes of the connecting holes according to the maximum process hole 9 during the part prefabrication stage.

Claims

1. A method for determining a process hole of a part connection hole in an assembly, wherein a theoretical model of the assembly is known, the assembly comprises at least two or more butted parts, the parts are provided with connection holes, and when the parts are not assembled, the connection holes are made into process holes, the aperture of the process holes is smaller than the theoretical aperture of the connection holes, and the aperture of the process holes is as close as possible to the theoretical aperture of the connection holes, characterized in that The following contents are included: 1) Generate an analysis digital model of the assembly based on the theoretical model of the assembly, which includes the matching constraint relationship of the docking parts; 2) Simplify and lighten the analysis digital model to establish a three-dimensional process tolerance simulation analysis model; 3) In the simulation analysis model, take the part where the connection hole is located as a reference, sort out all the parts that have contact constraints and matching constraints on the part, and create an assembly relationship; 4) In the simulation analysis model, tolerances are defined for the contact constraints and fit constraints of all parts in the assembly relationship; 5) In the simulation analysis model, a measurement relationship for the connecting hole on the part is established, and the measurement relationship is used to measure the hole center offset of the connecting hole or the hole-to-hole interference between the connecting hole and the connecting hole of the docking part; 6) Run the above simulation analysis model to simulate the assembly to obtain the hole center offset of the connecting hole or the maximum hole-to-hole interference; 7) According to the hole center offset or the maximum hole-to-hole interference, the maximum process aperture of the connecting hole on the part is calculated; 8) According to the maximum process aperture, the process hole of the connecting hole is made in the part prefabrication stage.

2. The method for determining the process holes of the part connection holes in the assembly according to claim 1, characterized in that: In step 7), the maximum diameter process hole of the connecting hole is obtained by using the aperture compensation hole center offset or the hole-hole interference, and the process hole is inscribed in the theoretical hole of the connecting hole in the assembly theoretical model.

3. The method for determining the process holes of the part connection holes in the assembly according to claim 1, characterized in that: In step 7), if the number of connecting holes on a part in the assembly is less than 10, the maximum process aperture of the connecting holes on the part is calculated by using the maximum interference between holes.

4. The method for determining the process holes of the part connection holes in the assembly according to claim 1, characterized in that: In step 5), when establishing the measurement relationship of the connection holes on the parts, if there is no corresponding part connection hole on the connection hole on the assembly part to be analyzed in the simulation analysis model, the theoretical position of the connection hole on the assembly part to be analyzed is used as a reference to establish the measurement relationship between the connection hole on the assembly part and the connection hole at the theoretical position.

5. The method for determining the process holes of the part connection holes in the assembly according to claim 1, characterized in that: In step 7), when converting according to the hole center offset or the maximum interference between holes, the connection hole of the part that is docked with the part where the connection hole to be analyzed is located is used as a reference, and the connection hole of the docking part is defaulted to be in the theoretical position of the assembly model.

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