A method for processing a fine boring support hole

Abstract

The application discloses a method for processing a fine boring support hole and belongs to the technical field of machining; the method is based on the user macro program function of a numerical control system, a general macro program with structure solidification and no mode selection variable is called, and self-adaptive fine boring processing of an intermittent coaxial hole system is realized; the method comprises the following steps: positioning to a processing starting point; calling a macro program and inputting an initial tool relief distance parameter and alternately appearing hole section thickness and hole gap parameters in a sequential assignment mode; a sequential execution state machine based on parameter existence is adopted in the macro program, a processing section number is automatically identified through continuous IF condition judgment, and corresponding processing units are executed; after one side processing is completed, a coordinate mirror image function is automatically activated to process the other side hole system. According to the application, an operator can directly input parameters according to drawing size without any calculation, the program body is not modified with the change of the number of processing holes, programming efficiency and program universality are remarkably improved, and the processing efficiency and precision are improved through air block rapid movement and mirror image processing.

Description

Technical Field

[0001] This invention relates to the field of machining technology, and more specifically, to a method for precision boring of support holes on CNC milling machines or machining centers, particularly a method for achieving efficient adaptive precision boring of intermittent coaxial hole systems based on user macro programs. Background Technology

[0002] In the field of mechanical manufacturing, especially in the machining of large structural components such as injection molding machine templates, machine tool spindle boxes, and reducer housings, a discontinuous coaxial hole system structure is widely used. Because this type of hole system has cavities, grooves, or relief grooves in the axial direction, it cannot be continuously bored in one go. Traditional machining strategies require the boring process to be performed in segments.

[0003] Currently, the following technical solutions are mainly used in this field for precision boring of such discontinuous holes: Option 1: Manual Programming Segmented Machining Method. The operator manually calculates the Z-axis coordinates of each bearing hole end face based on the part drawing, and uses linear interpolation (G01) commands in conjunction with fixed boring cycles (such as G76) to write the machining program segment by segment. In this method, the tool still needs to move at the cutting feed rate in the gap area between holes, resulting in a significant waste of non-cutting time. Furthermore, when the part structure is symmetrical, separate programs for both sides or two calls to the same program are required, resulting in lengthy programs, low programming efficiency, and a high risk of errors.

[0004] Option 2: Parametric Machining Based on Macro Programming. To overcome the shortcomings of manual programming, existing technologies have developed parametric programming methods using macro programs. For example, Chinese patent application CN118635556A discloses a process for integral drilling of pin holes in the top beam of a hydraulic support. This process utilizes a machine tool probe and a macro program for coordinate positioning and drilling. This solution automatically sets the workpiece coordinate system and determines the drilling position through the macro program, improving programming efficiency to some extent. However, this technical solution mainly focuses on using the probe for coordinate measurement and positioning. Its macro program logic is still a fixed-mode programming for a specific number of holes, and it does not solve the technical problem of needing to modify the program structure or set mode selection variables when the number of intermittent holes changes. Therefore, the program's versatility and adaptive machining capabilities still need improvement.

[0005] Specifically, the existing macro programs have the following technical problems when machining discontinuous holes: 1. Complex parameter input: It is necessary to calculate the machining depth of each bracket hole in turn and assign different parameters to each hole. The calculation process is tedious and prone to errors.

[0006] 2. Poor program adaptability: When the number of bracket holes changes, it is often necessary to modify the internal structure of the program or set additional mode selection parameters (such as using variable W to distinguish between two-hole / three-hole modes), which increases the complexity of programming and the possibility of errors.

[0007] 3. Double-sided machining requires repeated programming: When machining symmetrical hole systems on both sides, it is usually necessary to position twice or call the program twice, which affects machining efficiency.

[0008] Therefore, how to further simplify the programming process so that the machining program can adapt to machining different numbers of support holes while maintaining the stability and versatility of the program body is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0009] The purpose of this invention is to overcome the shortcomings of the prior art and provide a precision boring method for bracket holes, aiming to provide a highly efficient precision boring solution that is intuitive to program, requires no complex calculations, and can adapt to the machining of different numbers of bracket holes.

[0010] To achieve the above objectives, the present invention provides the following technical solution: A method for precision boring of bracket holes, characterized in that the method is based on the user macro program function of the CNC system, and by calling a general macro program with fixed structure and no mode selection variables, adaptive precision boring of any number of discontinuous bracket hole systems on the part can be achieved. The method includes the following steps: Step 1: Establish the workpiece coordinate system and quickly position the tool to the starting point above the hole system to be machined; Step 2: Call the preset general precision boring macro program and input a set of parameters in the call command in a sequential manner; the parameter sequence includes an initial tool deflection distance parameter, and subsequent alternating hole segment thickness parameters and hole gap parameters; Step 3: The macro program internally employs a sequential execution state machine based on parameter existence. It uses consecutive IF conditional statements to check whether subsequent parameters have been assigned values, and determines whether to execute the machining logic for the next hole segment based on the check results. This state machine design makes the program body itself fixed, containing no branch jump instructions for selecting machining modes. Its adaptive response to the number of machining segments depends entirely on the presence or absence of input parameters, rather than a mode variable controlling the program flow. Step 4: After completing the machining of the hole system on one side, the macro program automatically activates the coordinate axis mirroring function to machine the symmetrical hole system on the other side. Step 5: After machining is completed, the tool returns to a safe height, the macro program ends and returns to the main program.

[0011] As a preferred embodiment of the present invention, the macro program calling instruction format is: G65P7217A_B_C_D_E_...R_F_; where R is the initial tool deflection distance parameter; A, C, E... are hole segment thickness parameters; B, D... are hole gap parameters. The number of parameters varies according to the actual number of bracket holes. When machining two holes, A, B, C, R are input; when machining three holes, A, B, C, D, E, R are input, and so on.

[0012] As a preferred embodiment of the present invention, the core logic of the sequential execution state machine based on parameter existence is as follows: The macro program receives input parameters A, B, C, D, E, etc., sequentially through local variables #1, #2, #3, #4, #5… The main body of the program consists of multiple processing units with identical structures connected in series. Each processing unit is responsible for processing one hole segment, and at the end of the unit, a statement `IF[#variable_numberEQ#0]GOTO` is used to determine whether the next key parameter exists. If it exists, the next processing unit is executed sequentially; if it does not exist, the entire processing loop is exited directly.

[0013] As a preferred embodiment of the present invention, the function implemented inside the processing unit is as follows: based on the cumulatively calculated starting depth of the current hole segment, the tool is controlled to perform boring at a cutting feed rate G01, and then the tool is controlled to move to the starting point of the next hole segment in the neutral area at a rapid traverse speed G00.

[0014] Compared with the prior art, the present invention has the following beneficial effects: 1. Intuitive programming, eliminating calculation errors: This invention directly uses the dimensions marked on the drawings as input parameters for the macro program. Operators do not need to perform any depth conversion or cumulative calculations, thus completely eliminating the root cause of calculation errors and greatly improving programming efficiency.

[0015] 2. Fixed Program and Strong Adaptability: Due to the adoption of a "parameter-based sequential execution state machine," the macro program is fixed and does not change with the processing object. Therefore, when the number of bracket holes changes, the program can automatically identify and execute the corresponding processing based on the number of input parameters, without needing to modify the program body or set mode selection variables, greatly improving the program's versatility and adaptability.

[0016] 3. One-time tool setting, double-sided machining: By calling the coordinate mirroring function, this invention only needs to set a machining start coordinate point to automatically complete the machining of symmetrical hole systems on both sides of the part, avoiding the trouble of repeated tool setting and secondary programming.

[0017] 4. Significantly improved processing efficiency: The program automatically controls the tool to jump quickly in the neutral area and feed at the cutting speed in the area with material, minimizing non-processing time. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the dimensions of the double-bracket hole to be processed in Embodiment 1 of the present invention. The diagram shows the dimensional relationships of the first hole thickness A, the hole gap B, the second hole thickness C, and the initial tool deflection distance R.

[0019] Figure 2 This is a flowchart illustrating the logic of the macro program of this invention. The flowchart shows the core logic of the sequential execution state machine based on parameter existence. The macro program automatically determines the number of processing units to be executed by continuously checking whether the input parameters exist, thereby achieving adaptive processing of different numbers of support holes.

[0020] Figure 3 This is a program call sequence diagram for machining the double support hole according to the present invention. The diagram shows the interaction process between the macro program and the CNC system after the main program calls the macro program O7217, including coordinate saving, tool movement path, switching between cutting feed and rapid traverse, and automatic activation of the mirror function.

[0021] Figure 4 This is an example diagram of a program for manually programming bracket holes. The diagram shows the program code for machining intermittent bracket holes using the traditional manual programming method (G01 / G76), which is lengthy and contains a large number of repetitive instructions.

[0022] Figure 5 This is an example diagram of a program for machining bracket holes using a traditional macro program. The diagram shows the program code for machining the same part using existing macro programming technology (which requires setting the mode selection variable W). The program contains branch jump instructions to distinguish machining modes.

[0023] Figure 6 This is an example diagram of the program for machining double-bracket holes according to the present invention. The diagram shows the main program call instructions when machining double-hole parts using the method of the present invention. The parameter sequence corresponds exactly to the dimensions on the drawing, and the program is concise and intuitive.

[0024] Figure 7 This is a schematic diagram of the dimensions of the three bracket holes to be processed in Embodiment 2 of the present invention. The diagram shows the dimensional relationships of the three hole segments (A, C, E) and the two gaps (B, D).

[0025] Figure 8 This is an example diagram of the program for machining three support holes according to the present invention. The diagram shows the main program call instructions when machining three-hole parts using the same macro program. By adding input parameters (A, B, C, D, E), it automatically adapts to the machining requirements of three holes, and the macro program body does not need any modification.

[0026] Figure 9This is a schematic diagram of the Z-axis path of the tool according to the present invention. The diagram shows the movement pattern of the tool in the Z-axis direction, including the alternating process of rapid traverse (G00) across the neutral area and cutting feed (G01) machining the hole section area, and the Z-coordinate calculation formulas for each key position are marked. Detailed Implementation

[0027] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0028] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," and "circumferential" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0029] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0030] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0031] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can mean that the first feature is in direct contact with the second feature, or that the first feature is in indirect contact with the second feature through an intermediate medium. Furthermore, "above," "over," and "on top" of the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0032] It should be noted that when an element is referred to as being "fixed to" or "set on" another element, it can be directly on the other element or there may be an intervening element. When an element is considered to be "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and similar expressions used herein are for illustrative purposes only and do not represent the only possible implementation.

[0033] Example 1: Machining double support holes: This embodiment is used for processing such as Figure 1 The part shown has two intermittent support holes. This part needs to be machined with two holes located on the same axis, spaced apart. The first hole has a thickness A = 20 mm and a gap B = 80 mm, the second hole has a thickness C = 20 mm, and the initial tool clearance distance R = 5 mm.

[0034] First, the operator moves the tool to the safe starting point (X0, Y0) above the hole system on the CNC machine tool's control panel, according to the workpiece coordinate system settings.

[0035] Then, the macro program O7217, which is pre-stored in the machine tool's memory, is invoked. The core logic of this macro program is as follows: Figure 2 As shown, a sequential execution state machine design based on parameter existence is adopted. When the macro program is called, its internal execution flow is as follows: Figure 3 As shown.

[0036] The main program that calls the macro is as follows: % O1000 (Main Program) G90G54G00X0Y0 G43Z50.H01 M03S1000 G65P7217A20.B80.C20.R5.F60 G80G00Z100. M30 % In this invocation instruction, the parameter sequence and Figure 1 The dimensions on the drawing are completely consistent: A20 represents the thickness of the first hole, 20mm; B80 represents the gap, 80mm; C20 represents the thickness of the second hole, 20mm; R5 represents the initial deflection distance, 5mm; and F60 represents the feed rate, 60mm / min.

[0037] The specific code for macro program O7217 is as follows: % O7217 (ROUGHBORINGMACRO) IF[#1EQ#0]THEN#3000=1(PLEASEINPUTA) IF[#2EQ#0]THEN#3000=1(PLEASEINPUTB) IF[#3EQ#0]THEN#3000=1(PLEASEINPUTC) IF[#18EQ#0]THEN#3000=1(PLEASEINPUTR) #10=#5041 #11=#5042 #12=200 #17=0.2 N111 (First side machining - first hole) G90G0X#10Y#11 G0Z-[#18-5] G1Z-[#1+#18+5]F#9M8 G0Z-[#2+#1+#18-5] G1Z-[#3+#2+#1+#18+5]F#9 (Determine if there are subsequent hole segments) IF[#8EQ#0]GOTO444 (If a third hole exists, continue processing here) ... N444 (Mirror image processing of the other side) G51.1Y0 G90G0X#10Y#11 G0Z-[#18-5] G1Z-[#1+#18+5]F#9M8 G0Z-[#2+#1+#18-5] G1Z-[#3+#2+#1+#18+5]F#9 (Determine if there is a subsequent hole segment on the other side) IF[#8EQ#0]GOTO999 N999 M99 % Figure 4 , Figure 5 , Figure 6 Examples of programs for machining the same part are shown, including manual programming, traditional macro programming, and the method of this invention. The comparison demonstrates that the method of this invention has the simplest program and requires no additional calculations.

[0038] Example 2: Machining three support holes: This embodiment is used for processing such as Figure 7 The part shown has three discontinuous support holes. The thickness of each hole is 15mm, the gap between the holes is 30mm, and the initial tool clearance distance R=5mm.

[0039] The operation steps are exactly the same as in Example 1, and the main program is as follows: % O2000 G90G54G00X0Y0 G43Z50.H01 M03S1000 G65P7217A15.B30.C15.D30.E15.R5.F60 G80G00Z100. M30 % In this invocation instruction, the parameter sequence and Figure 7 The dimensions on the drawings correspond perfectly: A15 (first hole thickness), B30 (first gap), C15 (second hole thickness), D30 (second gap), E15 (third hole thickness), R5.

[0040] Calling the same macro program O7217, because the input parameters include parameter E (#5), the program's condition IF[#5EQ#0] after completing the second hole machining is false (i.e., E exists), so it will continue to execute the third hole machining logic, thus automatically adapting to the needs of three-hole machining. Figure 8 As shown.

[0041] To verify the technical effect of the present invention, a vertical machining center equipped with a FANUC0i-MF system was used. Figure 7 The three bracket hole parts shown (hole thickness 15mm×3, gap 30mm) were used as the object, and a comparative experiment was conducted under the same cutting conditions. The results are shown in Table 1.

[0042] Table 1. Comparison of the technical effects of different processing methods

[0043] Experimental results show that: 1. Significantly improved programming efficiency: The programming preparation time of this invention is only 5 minutes, which is 80% shorter than manual programming and 50% shorter than traditional macro programs. Moreover, the operator does not need to perform any calculations and can directly input parameters according to the drawing dimensions.

[0044] 2. Extremely simplified program structure: The program length of this invention is only 22 lines, which is 85.5% less than manual programming and 62.1% less than traditional macro programs. Moreover, the program body is fixed and does not need to be modified as the number of holes processed changes.

[0045] 3. Balancing processing efficiency and precision: The processing time of this invention is reduced by 35.9% compared to manual programming, and is comparable to the optimized traditional macro program; the coaxiality error on both sides is controlled within 0.026mm, which is superior to the two existing technologies.

[0046] Figure 9 The method of this invention further demonstrates the optimized tool path in the Z-axis direction. The organic combination of cutting feed and rapid traverse is the key to improving machining efficiency; specifically, Table 2 below shows... Figure 9 The following table shows the Z-axis path parameter descriptions: Table 2. Z-axis path parameter description

[0047] Note: A, B, C, D, and E are the thickness and clearance parameters of each hole, respectively, and R is the initial tool deflection distance.

[0048] In summary, the precision boring method for bracket holes provided by this invention, through a sequential execution state machine design based on parameter existence, achieves complete decoupling between program structure and the number of machining objects, providing a precision boring solution that is extremely simple to program, highly adaptable, and efficient in operation. While maintaining high-efficiency machining, it significantly reduces programming difficulty and error risk, achieving an organic unity between programming convenience and machining versatility.

[0049] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0050] The embodiments described above are merely illustrative of several implementations of the present invention, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of the present invention, and these all fall within the protection scope of the present invention. Therefore, the protection scope of this invention patent should be determined by the appended claims.

Claims

1. A method for precision boring a support hole, characterized in that, Includes the following steps: Step 1: Establish the workpiece coordinate system and quickly position the tool to the starting point above the hole system to be machined; Step 2: Call the preset precision boring macro program and input a set of parameters in the call command in a sequential manner; the parameter sequence includes an initial tool deflection distance parameter R, and subsequent alternating hole segment thickness parameters and hole gap parameters; Step 3: The macro program internally adopts a sequential execution state machine based on parameter existence. It checks whether subsequent parameters have been assigned values ​​through continuous IF conditional statements, and decides whether to execute the processing logic of the next hole segment based on the check results. The main body of the macro program is composed of multiple processing units with the same structure connected in series. Each processing unit is responsible for processing one hole segment, and at the end of the unit, it checks whether the next key parameter exists. If it exists, the next processing unit is executed sequentially. If it does not exist, the processing loop is directly exited. Step 4: After completing the machining of the hole system on one side, the macro program automatically activates the coordinate axis mirroring function to machine the symmetrical hole system on the other side. Step 5: After machining is completed, the tool returns to a safe height, the macro program ends and returns to the main program.

2. The method for machining a precision boring support hole according to claim 1, characterized in that, The macro program call instruction format in step 2 is: G65 P7217 A_ B_ C_ D_ E_ ... R_ F_; where R is the initial tool deflection distance parameter; A, C, E... are the hole section thickness parameters; B, D... are the hole gap parameters; F is the feed rate parameter; the number of parameters varies according to the actual number of support holes. When machining two holes, input A, B, C, R; when machining three holes, input A, B, C, D, E, R, and so on.

3. The method for machining a precision boring support hole according to claim 1, characterized in that, The sequential execution state machine based on parameter existence in step 3 is specifically implemented as follows: The macro program receives input parameters A, B, C, D, E, etc. sequentially through local variables #1, #2, #3, #4, #5...; At the end of each processing unit, a condition judgment instruction IF [#variable_numberEQ #0] GOTO is set to jump out of the label to determine whether the thickness parameter of the next hole segment exists.

4. The method for machining a precision boring support hole according to claim 1, characterized in that, The function implemented in each processing unit in step 3 is as follows: based on the cumulatively calculated starting depth of the current hole segment, control the tool to perform boring at a cutting feed rate G01, and then control the tool to move to the starting point of the next hole segment in the neutral area at a rapid traverse speed G00.

5. The method for machining a precision boring support hole according to claim 1, characterized in that, The coordinate axis mirroring function in step 4 is implemented through the G51.1 command. After the hole system on one side is machined, the macro program reads the current tool position, executes the mirroring command G51.1 Y0 about the Y axis, so that the tool automatically moves to the symmetrical machining start position on the other side and repeats the same machining path logic.

6. The method for machining a precision boring support hole according to claim 1, characterized in that, The macro program has a fixed structure and does not contain any branch jump instructions or mode selection variables for selecting the processing mode. The program's adaptive response to the number of support holes depends entirely on the number of input parameters.

7. The method for machining a precision boring support hole according to claim 1, characterized in that, Before execution, the macro program first checks the input parameters. It uses an IF conditional statement to confirm whether the necessary input parameters (A, B, C, R) have been assigned values. If any necessary parameter is missing, the program will issue an alarm and prompt for input.

8. The method for machining a precision boring support hole according to claim 1, characterized in that, The macro program saves the starting point coordinates to a local variable during execution, which is used to return to the starting position after the mirror processing is completed.

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