Precise special-shaped photoelectric system load frame machining clamping deformation control method

Abstract

The invention belongs to the technical field of precision machinery manufacturing, and particularly relates to a precision special-shaped photoelectric system load frame machining clamping deformation control method. The process design process comprises the following steps: firstly, designing a process table to complement the appearance structure of the special-shaped frame, then designing a stress division groove to reduce the deformation influence of the processing stress of the process table on the part, and then designing a fine clamping tool to reduce the clamping deformation of the fine machining of the part. And finally, the three-wheel machining technological procedure of rough machining, semi-finish machining and finish machining is designed, and a reasonable stress releasing method is formulated. Compared with the prior art, the problem of deformation of the special-shaped frame caused by insufficient clamping rigidity, residual stress release and clamping force in the rough machining process and the finish machining process is systematically solved, and therefore the final machining precision of parts is remarkably improved.

Description

Technical Field

[0001] This invention belongs to the field of precision mechanical manufacturing technology, specifically, it relates to a method for controlling the deformation of a precision irregular-shaped optoelectronic system load frame during processing and clamping. Background Technology

[0002] The precision irregular-shaped load frame of the optoelectronic system (hereinafter referred to as "irregular frame") is a core structural component of the optoelectronic system, used to support and position key optical components such as lasers, optical lens groups, and zoom mechanisms. Its machining accuracy, especially its geometric tolerances, directly determines the system accuracy, such as coaxiality and parallelism, between the various optical components, and is crucial to the overall performance of the optoelectronic system. Furthermore, these parts typically have complex structures, thin walls, and irregular shapes (asymmetric, irregular contours), making them typical difficult-to-machine structural components. During machining, especially in the roughing stage where most of the material is removed, significant machining stresses are generated and remain within the part.

[0003] The following methods are commonly used in the prior art to process such parts: 1) Dedicated contouring fixture: The fixture is designed according to the final shape of the part to provide support and clamping. However, this method is difficult to design support points for irregularly shaped parts, and it cannot avoid the deformation of the blank caused by stress release after rough machining. During finish machining, the blank itself already has initial stress deformation, making it difficult to guarantee the final accuracy.

[0004] 2) Low-melting-point alloy filling: The hollow parts of the parts are wrapped or filled with low-melting-point alloys to enhance rigidity. This method is complicated, requires additional alloy melting and cleaning equipment, and the alloy cooling process may introduce new stresses. It is costly and environmentally unfriendly.

[0005] 3) Optimize cutting parameters: Reduce cutting forces by using cutting strategies such as small depth of cut and rapid feed. This method has a certain effect on controlling cutting thermal deformation, but it cannot fundamentally solve the deformation problem caused by clamping force and residual stress.

[0006] In summary, the existing technology has the following main problems: First, the rigidity of the roughing clamping is insufficient. The clamping of irregular parts is unstable during roughing, which easily causes vibration, affects the processing efficiency, and may cause surface damage. Second, stress release leads to deformation. After roughing, the internal stress of the part is rebalanced, causing the blank to deform. Using this deformed blank for finishing cannot produce high-precision products. Third, secondary deformation occurs during finishing clamping. Even in the finishing stage, the clamping force generated by the traditional clamping method is sufficient to cause elastic deformation of thin-walled irregular parts. When the clamp is released after processing, the part springs back, resulting in loss of precision.

[0007] Therefore, there is an urgent need in this field to propose a process method for controlling and reducing clamping deformation during the machining of load frame parts for precision irregular optoelectronic systems. Summary of the Invention

[0008] In view of the shortcomings of the prior art, the purpose of this invention is to provide a method for controlling the deformation of the loading frame of a precision irregular optoelectronic system during machining and clamping, so as to systematically solve the deformation problems caused by insufficient clamping rigidity, residual stress release and clamping force during the rough and fine machining of irregular frames, thereby significantly improving the final machining accuracy of the parts.

[0009] To achieve the above objectives, the present invention provides the following technical solution: A method for controlling deformation during the machining and clamping of a precision irregular-shaped optoelectronic system load frame includes the following steps: S1. Design process table: Design a process table that can complete the shape of the parts according to the part shape of the load frame of the precision irregular optoelectronic system. S2. Design stress dividing groove: Set stress dividing groove between the part and the process table to reduce the influence of the process table's processing stress on the part's deformation. S3. Design precision clamping fixtures: Design corresponding precision clamping fixtures according to the shape of the parts and the process table to reduce the clamping deformation during the precision machining of the parts. S4. Design process and machining procedure: Design the process and machining procedure according to the three-round machining route of "rough machining - semi-finishing - finishing" to gradually remove machining stress and control the final deformation of the parts.

[0010] Preferably, in step S1, the process table is completed into a rectangle or circle according to the shape of the part, so as to facilitate clamping with flat-jaw pliers or three-jaw pliers, and the connection of the process table can enhance the rigidity of the part.

[0011] Preferably, in step S1, based on finite element analysis, corresponding positioning points and clamping points are designed on the process table for the part with the strongest rigidity, and screw holes and positioning pin holes for clamping are designed on the process table according to the positions of the positioning points and clamping points, so as to avoid applying force directly to the thin-walled or cantilevered areas of the part.

[0012] Preferably, in step S1, two positioning pin holes are designed on the process table. The diameter of the positioning pin holes is between φ2 and φ8 mm, and the diameter tolerance of the positioning pin holes is controlled between 0 and +0.03 mm. The distance between the two positioning pin holes is designed according to the actual part conditions, and the distance tolerance is controlled between -0.05 and +0.05 mm.

[0013] Preferably, in step S1, a reasonably designed clamping groove is arranged on the process table, and the bottom of the clamping groove is 0.5~1mm lower than the positioning surface of the part, for clamping by screws.

[0014] Preferably, in step S1, the plane of the process table is flush with the positioning surface of the part, and the flatness is required to be within 0.015mm.

[0015] Preferably, in step S2, stress dividing grooves are provided at all connections between the process table and the part, and the stress dividing grooves are evenly distributed on both sides of the connection between the process table and the part to ensure effective isolation of processing stress from being transmitted to the part body. The width of the stress dividing groove is between 2 and 4 mm, which is determined by the diameter of the tool used in the machining, and the total depth of the stress dividing groove is calculated according to the empirical formula h = 0.65 × H, where H is the total thickness of the groove.

[0016] Preferably, in step S3, screw holes and positioning pins are provided on the positioning surface of the finishing fixture, and the screw holes and positioning pins correspond to the screw through holes and positioning pin holes for clamping.

[0017] Preferably, in step S3, the design of the finishing clamping fixture adopts a "one-sided two-pin" positioning method and a top-surface clamping method, and includes the following steps: S31. A support surface is provided at the part with the strongest rigidity; S32. Design the position of the positioning pin according to the positioning pin hole on the process table, so that the positioning pin protrudes 3~5mm from the support surface, and process a C1 chamfer at the top of the positioning pin. The positioning design accuracy is set to 1 / 3 of the accuracy of the part to be processed. S33. Use multi-point distributed clamping with screws. M3 socket head cap screws are used to directly clamp the parts, with a preload torque between 0.02 and 0.025 N·m. This torque range has been tested and verified to be sufficient to prevent part displacement during processing and to ensure that the clamping force does not cause the parts to deform beyond their elastic limit.

[0018] Preferably, the process procedure in step S4 includes the following steps: S41. On the blank with the process table, complete the rough machining of all areas of the part and the process table except for the contact surface with the finishing fixture and the surface that needs to be finished. S42. Machining stress-dividing grooves to obtain the rough-machined parts and process table; S43. Perform the first aging treatment on the rough-machined parts and process table; S44. Perform semi-finishing again on the contact surfaces of the parts and process table with the finishing fixture and the surfaces that need to be finished, to obtain semi-finished parts and process table. S45. Stabilize the semi-finished parts and process table. S46. Use precision clamping fixtures to clamp the parts and complete the finishing of all features; S47. Remove the process table by wire EDM to obtain the final part.

[0019] Preferably, in step S41, a machining allowance of 1~1.5mm is reserved during the rough machining process.

[0020] Preferably, in step S42, a machining allowance of 0.3~0.5mm is reserved during the semi-finishing process.

[0021] The working principle of this invention is as follows: during the blank design stage of the irregular frame, i.e., in the computer-aided design model, an additional "process table" structure is added to the outer edge of the part or the weak clamping area. This process table completes the irregular and incomplete irregular contour into a regular, easy-to-clamp geometry (such as a rectangle or circle). During the roughing stage, the process table is used for stable clamping, greatly enhancing the rigidity of the part and ensuring efficient and stable roughing. The stress dividing groove is designed to effectively isolate most of the cutting stress and deformation generated during roughing, keeping it mainly within the process table and minimizing its transmission to the part itself. This provides a stable part blank with minimal internal stress for subsequent finishing. The innovation of this method lies in the integrated design structure of the process table and stress dividing groove, quantifying the design method of the stress dividing groove, achieving high structural integration, and actively controlling stress transmission; quantifying the preload of the clamping screws during clamping, changing the conventional tooling's experience-based clamping method, facilitating mass production control of part deformation, and effectively controlling deformation caused by part clamping during part processing. This invention has certain universality in the processing technology of irregular frames of different shapes, and can realize the clamping deformation control of irregular frame parts.

[0022] Compared with the prior art, the invention has the following beneficial effects: (1) Systematic: It provides a complete deformation control scheme from blank design, stress control, fine clamping to process arrangement, rather than local optimization.

[0023] (2) Proactive: Actively isolate and guide stress through stress dividing grooves, rather than passively compensate and correct after stress release.

[0024] (3) High rigidity guarantee: The process table design ensures optimal rigidity during the roughing stage, improving processing efficiency and surface quality.

[0025] (4) Quantitative control: The empirical parameter of clamping force for finishing is transformed into a quantifiable and repeatable torque parameter, which greatly improves process stability and product consistency.

[0026] (5) High precision guarantee: Through the comprehensive application of the above methods, the key form and position tolerances of precision irregular frame can be effectively controlled at the micron level, meeting the requirements of high-end optoelectronic systems.

[0027] In summary, this invention systematically solves the deformation problems caused by insufficient clamping rigidity, residual stress release, and clamping force during the roughing and finishing processes of irregularly shaped frames, thereby significantly improving the final machining accuracy of the parts. Attached Figure Description

[0028] The invention will be further described below with reference to the accompanying drawings and embodiments: Figure 1 This is a process flow diagram in Embodiment 1 of the present invention.

[0029] Figure 2 This is a top view of the part and process table in Embodiment 1 of the present invention.

[0030] Figure 3 This is a schematic diagram of the main structure of the part and the process table in Embodiment 1 of the present invention.

[0031] Figure 4 This is a schematic diagram of the right side structure of the part and the process table in Embodiment 1 of the present invention.

[0032] Figure 5 This is a schematic diagram of the left side structure of the part and the process table in Embodiment 1 of the present invention.

[0033] Figure 6 for Figure 5 Enlarged schematic diagram of Part I structure.

[0034] Figure 7 This is a top view of the structure of the part and the process table in Embodiment 1 of the present invention when they are clamped on the finishing fixture.

[0035] Figure 8 A front view of the part and the process table in Embodiment 1 of the present invention when they are clamped on the finishing fixture.

[0036] Figure 9 A schematic diagram of the left side of the part and the process table in Embodiment 1 of the present invention when they are clamped on the finishing fixture.

[0037] Figure 10 This is a three-dimensional model of the part and the process table in Embodiment 1 of the present invention.

[0038] Figure 11 This is a three-dimensional model of the part and the process table being clamped on the precision clamping fixture in Embodiment 1 of the present invention.

[0039] Figure 12 This is a top view of the part and process table in Embodiment 2 of the present invention.

[0040] In the diagram: 1-part, 2-process table, 3-screw through hole, 4-locating pin hole, 5-stress dividing groove, 6-screw, 7-base plate, 8-clamping groove, 9-locating pin. Detailed Implementation

[0041] The invention will now be clearly described in conjunction with the accompanying drawings and specific embodiments. This description is merely for illustrative purposes and is not intended to limit the invention. Any modifications, equivalent substitutions, or improvements made by those skilled in the art based on the embodiments of the invention without inventive effort to obtain all other embodiments should be included within the scope of protection of the invention.

[0042] Example 1 The present invention will be further described below with reference to specific embodiments.

[0043] See Figure 1-11 As shown in this embodiment, a method for controlling the deformation of a precision irregular-shaped optoelectronic system load frame during machining and clamping is proposed. The process design flow is as follows: first, design the process table 2 to complete the external structure of the irregular-shaped frame (hereinafter referred to as "part"), then design the stress dividing groove 5 to reduce the influence of the machining stress of the process table on the deformation of part 1, then design the precision clamping fixture to reduce the clamping deformation of the part during precision machining, and finally design a three-round machining process specification of "rough machining - semi-finishing - finishing" and formulate a reasonable stress release method.

[0044] Specifically, the method for controlling deformation during the machining and clamping of a precision irregular-shaped optoelectronic system load frame proposed in this embodiment includes the following steps: S1. Design process table: Design a process table that can complete the shape of the parts according to the part shape of the load frame of the precision irregular optoelectronic system. S2. Design stress dividing groove: Set stress dividing groove between the part and the process table to reduce the influence of the process table's processing stress on the part's deformation. S3. Design precision clamping fixtures: Design corresponding precision clamping fixtures according to the shape of the parts and the process table to reduce the clamping deformation during the precision machining of the parts. S4. Design process and machining procedure: Design the process and machining procedure according to the three-round machining route of "rough machining - semi-finishing - finishing" to gradually remove machining stress and control the final deformation of the parts.

[0045] In this embodiment, the shapes of the parts and the process table are as follows: Figure 2-6 and Figure 10 As shown. Figure 2 The dashed lines represent the process table and stress dividing groove. Figure 10 In the diagram, the red area represents the process table, and the yellow area represents the stress dividing groove.

[0046] Continuing with the above embodiment, in step S1, the process table is completed into a rectangle according to the shape of the part to facilitate clamping, and the connection of the process table can enhance the rigidity of the part. Based on finite element analysis, corresponding positioning points and clamping points are designed on the process table for the parts with the strongest rigidity. According to the positions of the positioning points and clamping points, screw through holes 3 and positioning pin holes 4 are designed on the process table to avoid direct force on the thin-walled or cantilevered areas of the part. The diameter of the screw through holes is φ3.5mm.

[0047] Specifically, two positioning pin holes are designed on the process table. The diameter of the positioning pin holes is φ6 + 0.03 mm, and the diameter tolerance of the positioning pin holes is controlled between 0 and +0.03 mm. The distance between the two positioning pin holes is designed according to the actual part conditions, and the distance tolerance is controlled between -0.05 and +0.05 mm.

[0048] Continuing with the above embodiment, in step S2, stress dividing grooves are provided at all connections between the process table and the part, and the stress dividing grooves are evenly distributed on both sides of the connection between the process table and the part to ensure effective isolation of processing stress from being transmitted to the part body. The width of the stress dividing groove is 4mm and the depth is 1mm.

[0049] like Figure 7-9 and Figure 11 As shown, in step S3 of this embodiment, screw holes and positioning pins 9 are provided on the positioning surface of the finishing clamping fixture. The screw holes and positioning pins correspond to the through holes of the clamping screws and the holes of the positioning pins. The finishing clamping fixture is designed with a "one-sided, two-pin" positioning method and a top-surface clamping method, and includes the following steps: S31. A support surface is provided at the part with the strongest rigidity; S32. Design the position of the positioning pin according to the positioning pin hole on the process table, so that the positioning pin protrudes 3~5mm from the support surface, and process a C1 chamfer at the top of the positioning pin. The positioning design accuracy is set to 1 / 3 of the accuracy of the part to be processed. S33. Use multi-point distributed clamping with screws. M3 socket head cap screws are used to directly clamp the parts, with a preload torque between 0.02 and 0.025 N·m. This torque range has been tested and verified to be sufficient to prevent part displacement during processing and to ensure that the clamping force does not cause the parts to deform beyond their elastic limit.

[0050] like Figure 7-9As shown, the precision clamping fixture is prepared using a base plate 7, designed according to the shape of the part. For areas requiring clearance, gaps need to be machined into the base plate. The surface of the mounted part must have a flatness within 0.01mm. The base plate is secured to the machine tool worktable with two M12 hex socket screws. Four M3 hex socket screws 6 are used, distributed at the four corners of the part, with a preload of 0.2~0.25 N·m.

[0051] Following the above embodiments, the process procedure in step S4 includes the following steps: S41. On the blank with the process table, complete the rough machining of all areas of the part and the process table except for the contact surface with the finishing fixture and the surface that needs to be finished. Leave a machining allowance of 1~1.5mm during the rough machining process. S42. Machining stress-dividing grooves to obtain the rough-machined parts and process table; S43. Perform the first aging treatment on the rough-machined parts and process table; S44. Perform semi-finishing again on the contact surfaces of the parts and process table with the finishing fixture and the surfaces that need to be finished. Leave a machining allowance of 0.3~0.5mm during the semi-finishing process to obtain the semi-finished parts and process table. S45. Stabilize the semi-finished parts and process table. S46. Use precision clamping fixtures to clamp the parts and complete the finishing of all features; S47. Remove the process table by wire EDM to obtain the final part.

[0052] The working principle of this invention is as follows: during the blank design stage of the irregular frame, i.e., in the computer-aided design model, an additional "process table" structure is added to the outer edge of the part or the weak clamping area. This process table completes the irregular and incomplete irregular contour into a regular, easy-to-clamp geometry (such as a rectangle or circle). During the roughing stage, the process table is used for stable clamping, greatly enhancing the rigidity of the part and ensuring efficient and stable roughing. The stress dividing groove is designed to effectively isolate most of the cutting stress and deformation generated during roughing, keeping it mainly within the process table and minimizing its transmission to the part itself. This provides a stable part blank with minimal internal stress for subsequent finishing. The innovation of this method lies in the integrated design structure of the process table and stress dividing groove, quantifying the design method of the stress dividing groove, achieving high structural integration, and actively controlling stress transmission; quantifying the preload of the clamping screws during clamping, changing the conventional tooling's experience-based clamping method, facilitating mass production control of part deformation, and effectively controlling deformation caused by part clamping during part processing. This invention has certain universality in the processing technology of irregular frames of different shapes, and can realize the clamping deformation control of irregular frame parts.

[0053] Example 2 like Figure 12 As shown, the difference between this embodiment and embodiment 1 is only that in step S1, a reasonably designed clamping groove 8 is arranged on the process table. The bottom of the clamping groove is 0.5~1mm lower than the positioning surface of the part, and is used for clamping by screws.

[0054] The above description is merely a preferred embodiment of the present invention and is not limited to the disclosed embodiments. Many modifications and variations will be apparent to those skilled in the art without departing from the scope and spirit of the described embodiments.

Claims

1. A method for controlling deformation during the machining and clamping of a precision irregular-shaped optoelectronic system load frame, characterized in that, The process includes the following steps: S1, Design the process table: Design a process table that can complete the shape of the parts according to the part shape of the load frame of the precision irregular optoelectronic system. S2. Design stress dividing groove: Set stress dividing groove between the part and the process table to reduce the influence of the process table's processing stress on the part's deformation. S3. Design precision clamping fixtures: Design corresponding precision clamping fixtures according to the shape of the parts and the process table to reduce the clamping deformation during the precision machining of the parts. S4. Design process and machining procedure: Design the process and machining procedure according to the three-round machining route of "rough machining - semi-finishing - finishing" to gradually remove machining stress and control the final deformation of the parts.

2. The method for controlling deformation during machining and clamping of a precision irregular-shaped optoelectronic system load frame according to claim 1, characterized in that, In step S1, the process table is completed into a rectangle or circle according to the shape of the part.

3. The method for controlling deformation during machining and clamping of a precision irregular-shaped optoelectronic system load frame according to claim 1, characterized in that, In step S1, based on finite element analysis, corresponding positioning points and clamping points are designed on the process table for the part with the strongest rigidity. And according to the position of the positioning points and clamping points, mounting screw through holes and positioning pin holes are designed on the process table.

4. The method for controlling deformation during machining and clamping of a precision irregular-shaped optoelectronic system load frame according to claim 3, characterized in that, In step S1, two positioning pin holes are designed on the process table. The diameter of the positioning pin holes is between φ2 and φ8 mm, and the diameter tolerance of the positioning pin holes is controlled between 0 and +0.03 mm. The distance between the two positioning pin holes is designed according to the actual part conditions, and the distance tolerance is controlled between -0.05 and +0.05 mm.

5. The method for controlling deformation during machining and clamping of a precision irregular-shaped optoelectronic system load frame according to claim 1, characterized in that, In step S2, stress dividing grooves are provided at all connections between the process table and the part, and the stress dividing grooves are evenly distributed on both the front and back sides of the connection between the process table and the part. The width of the stress dividing groove is between 2 and 4 mm, and the total depth of the stress dividing groove is calculated according to the empirical formula h = 0.65 × H, where H is the total thickness of the groove.

6. The method for controlling deformation during machining and clamping of a precision irregular-shaped optoelectronic system load frame according to claim 3, characterized in that, In step S3, screw holes and positioning pins are provided on the positioning surface of the precision clamping fixture, and the screw holes and positioning pins correspond to the screw through holes and positioning pin holes for clamping.

7. The method for controlling deformation during machining and clamping of a precision irregular-shaped optoelectronic system load frame according to claim 6, characterized in that, The design of the finishing clamping fixture adopts a "one-sided two-pin" positioning method and a top-surface clamping method, and the design of the finishing clamping fixture includes the following steps: S31. A support surface is provided at the part with the strongest rigidity; S32. Design the position of the positioning pin according to the positioning pin hole on the process table, so that the positioning pin protrudes 3~5mm from the support surface, and process a C1 chamfer at the top of the positioning pin. The positioning design accuracy is set to 1 / 3 of the accuracy of the part to be processed. S33. Use multi-point distributed clamping with screws. When clamping, use M3 internal hex screws to directly clamp the parts. The pre-tightening torque is between 0.02 and 0.025 N·m.

8. A method for controlling deformation during machining and clamping of a precision irregular-shaped optoelectronic system load frame according to any one of claims 1 to 7, characterized in that, The process procedure in step S4 includes the following steps: S41. On the blank with the process table, complete the rough machining of all areas of the part and the process table except for the contact surface with the finishing fixture and the surface that needs to be finished. S42. Machining stress-dividing grooves to obtain the rough-machined part and process table; S43. Perform the first aging treatment on the rough-machined parts and process table; S44. Perform semi-finishing again on the contact surfaces of the parts and process table with the finishing fixture and the surfaces that need to be finished, to obtain semi-finished parts and process table. S45. Stabilize the semi-finished parts and process table. S46. Use precision clamping fixtures to clamp the parts and complete the finishing of all features; S47. Remove the process table by wire EDM to obtain the final part.

9. The method for controlling deformation during machining and clamping of a precision irregular-shaped optoelectronic system load frame according to claim 8, characterized in that, In step S41, a machining allowance of 1~1.5mm is reserved during the rough machining process.

10. The method for controlling deformation during machining and clamping of a precision irregular-shaped optoelectronic system load frame according to claim 9, characterized in that, In step S44, a machining allowance of 0.3~0.5mm is reserved during the semi-finishing process.

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