A method and device for processing circular arc thread arc top

Abstract

The present invention belongs to the technical field of thread processing, and specifically relates to a method and device for processing circular arc thread tops. The method comprises the following steps: determining a step angle when processing the top arc based on the tool tip radius, the top arc radius, and the surface roughness; calculating the rotation angle of each layer of tool during layered processing based on the step angle; calculating the offset coordinates of the tool when moving each layer based on the tool tip radius, the tooth profile parameters, and the rotation angle of each layer of tool; the tooth profile parameters include the top arc radius, the root arc radius, the tooth height, and the tooth profile angle; processing each layer according to the calculated offset coordinates and rotation angle of the tool when moving each layer, until the tool rotation angle is achieved to ensure consistent surface roughness while improving processing efficiency.

Description

Technical Field

[0001] The invention belongs to the technical field of thread processing, and particularly relates to a method and device for processing circular arc thread arc crests. Background Art

[0002] Threaded connection is a common connection method. Compared with ordinary metric threads, MJ threads, etc., arc threads have great advantages in processing and manufacturing, structural strength and fatigue resistance. For example, the Chinese invention patent application with application publication number CN109967982A discloses a method for preparing an arc thread anchor assembly for a wind turbine generator set, wherein the external thread on the anchor is a continuous arc thread, including a tooth top arc, a straight line segment, a tooth bottom arc, and a straight line segment connected in sequence, and the straight line segment is tangent to the tooth top arc and the tooth bottom arc respectively. Since the arc thread adopts a large pitch and non-uniform tooth thickness, not only is the axial fit clearance large, but it can also reduce stress concentration and improve fatigue resistance. In addition, the Chinese utility model patent with authorization announcement number CN209818480U discloses a high-strength arc thread connection pair. The arc thread connection pair adopts an arc thread tooth profile. The internal and external threads are in surface contact, and the force is evenly distributed. It can effectively reduce the stress concentration when the thread is loaded, and has good fatigue resistance. The patent discloses two arc thread structures with thread major diameters of 42 and 48, and pitches of 6.35 and 8.5 respectively. The patent with authorization announcement number CN116877555B discloses a double-headed stud for connecting the root of wind turbine blades and its processing method. The external thread of the double-headed stud thread section is an arc thread, and the nominal diameter d of the arc thread is 42 and 48 respectively. 公称 =36mm~40mm, arc thread pitch Pr=(0.153~0.192)d 公称 , the tooth height of the arc thread hr=(0.37~0.44)Pr, the minor diameter of the arc thread d1r=d 公称 -0.8746Pr. The tooth profile of the arc thread is a symmetrical structure, including two symmetrical arc tooth tops, two side lines and a tooth bottom. In traditional technology, the arc groove cutter is generally used to process the arc tooth top of the arc thread in a linear feed method with equal spacing, such as Figure 1As shown in the figure, the feed is performed at a spacing of Δh, and the total feed height is h. However, the surface roughness of the arc tooth top processed by the equal-interval linear feed method is highly discrete, and the processing efficiency is low. Therefore, in recent years, arc feed methods using equal-angle stepping based on polar coordinates, sine function or cosine function have also emerged. The arc feed method with equal-angle stepping can ensure that the roughness of the machined surface tends to be consistent, but its step angle is selected based on experience. When the step angle is too large, the roughness of the machined surface cannot be guaranteed. When the step angle is too small, the processing efficiency is too low. Therefore, in order to ensure surface roughness during processing, the step angle used is generally too conservative. Although the processing efficiency is improved compared to the equal-interval linear feed efficiency, it is still relatively low. Moreover, when the equal-angle stepping feed is used, due to the properties of the sine function and cosine function, the feed amount will gradually increase. When the feed amount exceeds the preset maximum feed amount, it will cause a reduction in tool life or even direct damage to the tool. Summary of the Invention

[0003] The object of the present invention is to provide a method and device for processing the arc top of an arc thread, so as to solve the problem that the existing method for processing the arc top of an arc thread cannot achieve consistent roughness and high processing efficiency at the same time.

[0004] In order to solve the above technical problems, the present invention provides a method for machining arc thread arc top, comprising the following steps:

[0005] 1) Determine the step angle when machining the tooth top arc based on the tool tip radius, tooth top arc radius and surface roughness;

[0006] 2) Calculate the rotation angle of each layer tool during layered processing based on the step angle;

[0007] 3) Calculate the offset coordinates of the tool when it moves at each layer based on the tool tip radius, tooth profile parameters, and the rotation angle of each layer of the tool; the tooth profile parameters include the tooth top arc radius, tooth bottom arc radius, tooth height, and tooth profile angle;

[0008] 4) Process each layer according to the calculated offset coordinates and rotation angle of the tool when it moves each layer, until the tool rotation angle reaches θ is the tooth angle.

[0009] Furthermore, in step 1), the step angle when machining the tooth top arc is determined according to the following formula:

[0010]

[0011] Where Δα is the step angle, R 刀 is the tool tip radius, R 顶 is the radius of the tooth top arc, R z is the surface roughness.

[0012] Furthermore, the method for calculating the rotation angle of each layer of tool during layered processing based on the step angle is: if the absolute value of the difference between the offset of the next layer rotation angle determined according to the current step angle in the radial feed direction of the turning tool and the offset of the current layer rotation angle in the radial feed direction of the turning tool is greater than the absolute value of the maximum feed amount, then the step angle is re-determined according to the maximum feed amount, and the rotation angle of the tool of the processing layer after the current layer is calculated based on the re-determined step angle.

[0013] Furthermore, the method for re-determining the step angle according to the maximum feed amount is to calculate the step angle according to the following formula:

[0014]

[0015] Among them, Δα′ is the re-determined step angle, X 顶 R is the X-direction offset of the center of the tooth top arc relative to the origin O, 顶 is the radius of the tooth top arc, R 刀 is the tool tip radius, X n is the X-direction offset of the tool position relative to the origin O, ΔX max is the maximum feed amount, α n is the tool rotation angle of the nth layer, the nth layer is the current layer, the origin O is the intersection of the tooth top and the tooth profile symmetry axis, the radial retraction direction of the turning tool is the positive X direction, the radial feed direction of the turning tool is the negative X direction, the positive direction of the angular momentum when the spindle rotates counterclockwise is the positive Z direction, and the negative direction of the angular momentum when the spindle rotates counterclockwise is the negative Z direction.

[0016] Furthermore, the tool tip radius must be greater than or equal to the tool minimum tool tip radius and less than or equal to the tool maximum tool tip radius; the tool maximum tool tip radius is determined based on the Z-direction offset of the tooth top arc center relative to the origin O, the tooth profile angle and the tooth top arc radius, the origin O is the intersection of the tooth top and the tooth profile symmetry axis, the radial retraction direction of the turning tool is the X positive direction, the radial feed direction of the turning tool is the X negative direction, the positive direction of the angular momentum when the spindle rotates counterclockwise is the Z positive direction, and the negative direction of the angular momentum when the spindle rotates counterclockwise is the Z negative direction; the tool minimum tool tip radius is the set multiple of the tool maximum tool tip radius, and the set multiple is greater than or equal to 1 / 3 and less than or equal to 1 / 2.

[0017] Furthermore, the maximum tool nose radius is determined according to the following formula:

[0018]

[0019] in, is the maximum tool tip radius, Z 顶 is the Z-direction offset of the center of the tooth top arc relative to the origin O, θ is the tooth profile angle, R 顶is the radius of the tooth top arc.

[0020] Furthermore, the method for calculating the offset coordinates of the tool when each layer moves is as follows: calculate the X-direction offset X of the tool position relative to the origin O n , Z direction offset Z of tool position relative to origin O n , and determine the number of cutters per layer according to the crest width and tool width. When the number of cutters per layer is two, the offset coordinates of each cutter when each layer moves are (X n , Z n ) and (X n , -Z n ); When there are three cutting tools per layer, the offset coordinates of each tool when each layer moves are (X n , Z n )、(X n ,0) and (X n , -Z n ); where X n and Z n The calculation formula is:

[0021] X n =X 顶 +(R 刀 +R 顶 )cos(α n )

[0022] Z n =Z 顶 -(R 刀 +R 顶 )sin(α n )

[0023] Among them, Z 顶 X is the Z-direction offset of the center of the tooth top arc relative to the origin O, 顶 R is the X-direction offset of the center of the tooth top arc relative to the origin O, 顶 is the radius of the tooth top arc, R 刀 is the tool tip radius, α n is the tool rotation angle of the nth layer, the origin O is the intersection of the tooth top and the tooth profile symmetry axis, the radial retraction direction of the turning tool is the positive X direction, the radial feed direction of the turning tool is the negative X direction, the positive direction of the angular momentum when the spindle rotates counterclockwise is the positive Z direction, and the negative direction of the angular momentum when the spindle rotates counterclockwise is the negative Z direction.

[0024] Furthermore, Z 顶 and X 顶 Calculated according to the following formula:

[0025]

[0026] X 顶=-R 顶

[0027] Among them, H is the tooth height.

[0028] Furthermore, the rotation direction of the tool during machining is counterclockwise.

[0029] The beneficial effects of the above technical solution are as follows: the present invention is a pioneering invention. When adopting equal-angle feed, the relationship between surface roughness and step angle is established, and the step angle is determined based on the surface roughness. Thus, the maximum step angle that can be achieved during processing can be selected to process the arc tooth top while ensuring the consistency of the processing surface roughness. This solves the problem that the step angle in the existing equal-angle processing cannot achieve both consistent roughness and high processing efficiency at the same time due to the experience-based selection. It ensures consistent surface roughness while also improving processing efficiency.

[0030] In order to solve the above technical problems, the present invention also provides a circular arc thread arc top processing device, including a processor, and the processor is used to execute computer program instructions to implement the circular arc thread arc top processing method introduced above.

[0031] The beneficial effects of the above technical solution are as follows: the present invention is a pioneering invention. When adopting equal-angle feed, the relationship between surface roughness and step angle is established, and the step angle is determined based on the surface roughness. Thus, the maximum step angle that can be achieved during processing can be selected to process the arc tooth top while ensuring the consistency of the processing surface roughness. This solves the problem that the step angle in the existing equal-angle processing cannot achieve both consistent roughness and high processing efficiency at the same time due to the experience-based selection. It ensures consistent surface roughness while also improving processing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 This is a schematic diagram of the tool path of the equidistant linear feed method in the prior art;

[0033] Figure 2 This is a flow chart of processing arc thread arc crests according to an embodiment of the method of the present invention;

[0034] Figure 3 is the calculation Z of the embodiment of the method of the present invention 顶 The geometric relationship diagram when

[0035] Figure 4 This is a geometric relationship diagram for calculating the maximum tool tip radius of a tool according to an embodiment of the method of the present invention;

[0036] Figure 5 Schematic diagram of tool trajectory during layered processing according to step angles in an embodiment of the method of the present invention;

[0037] Figure 6is a geometric relationship diagram for calculating the step angle in an embodiment of the method of the present invention;

[0038] Figure 7 This is a geometric relationship diagram when calculating the tool position coordinate value with the center of the tooth top arc as the origin in the embodiment of the method of the present invention;

[0039] Figure 8 Schematic diagram of the tool path for machining arc tooth tops in an embodiment of the method of the present invention;

[0040] Figure 9 This is a comparison chart of the traditional equal-spacing machining effect of an embodiment of the method of the present invention and the arc tooth top machining effect of the present invention. DETAILED DESCRIPTION

[0041] In order to make the objectives, technical solutions and advantages of the present invention more clear, the specific embodiments of the present invention are further described below with reference to the accompanying drawings.

[0042] The present invention adopts an equal-angle feed method to process the arc tooth top of an arc thread, establishes a relationship between the surface roughness and the step angle, and thus can select a maximum step angle. When the equal-angle feed is adopted, the step angle is also determined based on the surface roughness, and a relationship between the surface roughness and the step angle is established. The step angle is determined based on the surface roughness, so that the maximum step angle that can be achieved during processing can be selected to process the arc tooth top while ensuring the consistency of the processed surface roughness. This solves the problem that the step angle in the existing equal-angle processing cannot achieve both consistent roughness and high processing efficiency due to the experience-based selection of the step angle. While ensuring consistent surface roughness, the processing efficiency is also improved.

[0043] Method Example

[0044] The present invention is a method for processing circular arc thread top, taking the right side top as an example, Figure 2 The specific process is as follows:

[0045] 1. Determine the coordinates of the center of the tooth top arc (X 顶 , Z 顶 ).

[0046] The intersection of the tooth top and the tooth profile symmetry axis is taken as the origin O, the radial retraction direction of the turning tool is the positive X direction, the radial feed direction of the turning tool is the negative X direction, the positive direction of the angular momentum when the spindle rotates counterclockwise is the positive Z direction, the negative direction of the angular momentum when the spindle rotates counterclockwise is the negative Z direction, the tooth profile angle is θ, and the tooth top arc radius is R 顶 , the radius of the tooth bottom arc is R 底 , the center of the tooth bottom arc is O 底 , tooth height is H, calculate the center of the top arc O 顶 X-direction offset X relative to the origin O 顶and Z-direction offset Z 顶 , where X 顶 =-R 顶 The spindle refers to the rotating spindle of the lathe.

[0047] Specifically, according to Figure 3 The geometric relationship shown, Z 顶 The calculation formula is as follows:

[0048] Z 顶 =O 底 C+DF-EF+BG

[0049] in:

[0050]

[0051]

[0052] 2. Determine the tool tip radius based on the Z-direction offset of the tooth tip arc center relative to the origin O, the tooth profile angle, and the tooth tip arc radius. The tool tip radius must be greater than or equal to the tool's minimum tip radius and less than or equal to the tool's maximum tip radius.

[0053] In this embodiment, the tool uses an existing arc groove tool. Figure 4 The geometric relationship shown, the maximum tool tip radius The calculation formula is:

[0054]

[0055] To ensure machining efficiency, the minimum tool tip radius The maximum tool tip radius of the tool with the set multiple is greater than or equal to 1 / 3 and less than or equal to 1 / 2. Preferably, the set multiple is 1 / 3, that is:

[0056]

[0057] At this time, the tool nose radius R 刀 The selection range is:

[0058]

[0059] 3. Determine the step angle when machining the tooth top arc based on the surface roughness, and calculate the rotation angle of each layer of tool during layered machining based on the step angle.

[0060] like Figure 5 As shown in the figure, when the tool is moving, the center of the tooth top arc is used as the rotation axis, the vertical upward direction is the positive direction of the radius, and the counterclockwise direction is the positive direction of the rotation angle. The step angle Δα when machining the tooth top arc is used for layered machining, so that the rotation angle of the tool when machining the tooth top arc moves from 0° to Δα depends on the roughness R z OK, roughness R z Determine according to actual needs. Figure 6 As shown, O 刀 The center of the tool tip arc in the current layer, O′ 刀 is the center of the tool tip arc of the next layer, and the step angle between two adjacent layers is Δα. According to the cosine theorem, the calculation formula of Δα is as follows:

[0061]

[0062] α n =α n-1 +Δα,α n is the tool rotation angle of the nth layer, α n-1 is the tool rotation angle of the n-1th layer.

[0063] 4. Calculate the offset coordinates of the tool.

[0064] According to the tool tip radius, tooth profile parameters and the rotation angle of each layer of tool, the offset coordinates of the tool when moving each layer are calculated; the tooth profile parameters include the tooth top arc radius, tooth bottom arc radius, tooth height and tooth profile angle. Figure 7 As shown, for any layer n when machining the top arc, the tool rotation angle is α n , the tool position (i.e. the center of the tool tip arc) is relative to the tooth top arc origin O 顶 X-direction offset The calculation formula is:

[0065]

[0066] Tool position relative to the tooth top arc origin O 顶 Z-direction offset The calculation formula is:

[0067]

[0068] Perform coordinate transformation and take the center of the tooth top arc O 顶 The tool position coordinate value of the origin Convert to tool position coordinates (X n , Z n ), get the X-direction offset X of the tool position relative to the origin O n and the Z-direction offset Z of the tool position relative to the origin O n , and determine the number of cutters per layer according to the crest width and tool width. When the number of cutters per layer is two, the offset coordinates of each layer when moving are (X n , Z n ) and (X n, -Z n ); When the number of cutters per layer is three, the offset coordinates of each layer when moving are (X n , Z n )、(X n ,0) and (X n , -Z n ); where X n and Z n The calculation formula is:

[0069]

[0070] 5. Process each layer according to the calculated offset coordinates and rotation angle of the tool when it moves each layer, until the tool rotation angle reaches

[0071] Specifically, layered processing is performed from right to left based on the rotation angle and offset coordinates of each layer. Preferably, considering the rigid deformation of the guide rod, the tool rotates counterclockwise when the tool is moving, so that the material always supports the tool at the current processing position, effectively reducing the tool vibration phenomenon. Specifically, considering that the tooth profile is a symmetrical tooth profile, the first cut of each layer is counterclockwise relative to the center of the tooth top arc of the tooth side to be processed, and the last cut of each layer is counterclockwise relative to the center of the tooth top arc of the tooth side to be processed. Overall, it is tangent to the tooth top arc and rotates and offsets toward the tooth bottom. The rotation angle of each layer of tool is α n , process the corresponding layers at this angle, and (X n , Z n ) is used as the offset coordinate to process the first cut, then move to the left, with (X n , -Z n ) is used as the offset coordinate to process the second cut. If the tooth top width is too large and two cuts are not enough to cover the layer, the layer is processed with (X n , Z n ) is used as the offset coordinate to process the first cut, and then (X n ,0) is the offset coordinate for machining the second cut, and finally (X n , -Z n ) is the offset coordinate for machining the third cut.

[0072] When feeding from left to right in each layer in the opposite direction, first (X n , -Z n ) is used as the offset coordinate to process the first cut, and then (X n , Z n ) is used as the offset coordinate to process the second cut. If the tooth top width is too large, two cuts are not enough to cover the layer, then the layer is processed with (X n , -Z n ) is used as the offset coordinate to process the first cut, and then (X n,0) is the offset coordinate for machining the second cut, and finally (X n , Z n ) is the offset coordinate for machining the third cut.

[0073] In one embodiment, each layer is processed at equal angles according to the feeding method from right to left. n =nΔα. First calculate the angle of the first cut α1=Δα, and calculate the offset X1 and Z1 of the tool relative to point O in the X and Z directions, process the first layer at the angle of α1, and use (X1, Z1) as the offset coordinate to process the first cut, then move to the left and use (X1, -Z1) as the offset coordinate to process the second cut. If the tooth top width is too large and two cuts are not enough to cover the first layer, use (X1, Z1) as the offset coordinate to process the first cut, then use (X1, 0) as the offset coordinate to process the second cut, and finally use (X1, -Z1) as the offset coordinate to process the third cut. At this point, the first layer is processed. Then process the second layer at an angle of α2, α2=α1+Δα=2Δα, calculate X2 and Z2, and process according to the method of the first layer, and so on until the processing is completed. At this point, the top arc processing is completed, and the tool path is as follows Figure 8 As shown. Figure 9 As shown, Figure 9 The middle a is the traditional equal spacing processing diagram, Figure 9 Figure b is the processing effect diagram of the present invention. It can be seen that compared with the equal-interval processing diagram and the traditional equal-interval processing, the present invention has an equal feed distance along the arc direction when processing the arc tooth top, and the tooth top roughness is controllable and highly consistent.

[0074] As another embodiment, in order to avoid reducing the tool life when the feed amount exceeds the preset maximum feed amount, the present invention also considers the maximum feed amount ΔX when determining the step angle. max If the absolute value of the difference between the offset of the next layer rotation angle determined by the current step angle in the radial feed direction of the turning tool and the offset of the current layer rotation angle in the radial feed direction of the turning tool is greater than the absolute value of the maximum feed amount, the step angle is re-determined according to the maximum feed amount, and the rotation angle of the tool of the processing layer after the current layer is calculated according to the re-determined step angle. Specifically, for any n-layer tool offset coordinate (X n , Z n ), if the tool offset coordinates of the n+1 layer calculated according to the equal angle are (X n+1 , Z n+1 ), the absolute value of the difference in tool offset in the X direction |X n+1 -X n |Greater than the maximum feed ΔX max The absolute value of the maximum feed amount ΔX maxRe-determine the step angle Δα′ and use it to replace the value of Δα, and calculate the new n+1 tool offset coordinate (X′ n+1 , Z′ n+1 ), X′ n+1 To consider the X-direction offset of the tool position of the n+1th layer relative to the origin O when the maximum feed amount is taken into account, Z′ n+1 a′ is the Z-direction offset of the tool position of the n+1th layer relative to the origin O when considering the maximum feed amount. n+1 is the rotation angle of the n+1th layer when considering the maximum feed amount. Figure 7 The geometric relationship shown in the figure, the calculation formula of Δα′ is as follows:

[0075]

[0076] Z′ n+1 =Z 顶 -(R 顶 +R 刀 )sin(a′ n+1 )

[0077]

[0078] The calculated Δα′ is used as the new step angle to replace the original Δα and continue processing until the process is completed. Time processing.

[0079] Device embodiment

[0080] The present invention provides a device for machining an arc thread top, which is used to execute computer program instructions to implement the arc thread top machining method described in the above method embodiment. The device can be a CNC lathe for machining threads.

Claims

1. A method for machining circular arc thread tops, characterized in that: The steps include: 1) Determine the step angle when machining the top arc based on the tool tip radius, top arc radius and surface roughness; the step angle is determined according to the following formula: Where Δα is the step angle, R 刀 is the tool tip radius, R 顶 is the radius of the tooth top arc, R z is the surface roughness; 2) Calculate the rotation angle of each layer tool during layered processing based on the step angle; 3) Calculate the offset coordinates of the tool when it moves at each layer based on the tool tip radius, tooth profile parameters, and the rotation angle of each layer of the tool; the tooth profile parameters include the tooth top arc radius, tooth bottom arc radius, tooth height, and tooth profile angle; 4) Process each layer according to the calculated offset coordinates and rotation angle of the tool when it moves each layer, until the tool rotation angle reaches θ is the tooth angle.

2. The method for machining circular arc thread top according to claim 1, characterized in that: The method for calculating the rotation angle of each layer of tool during layered processing based on the step angle is as follows: if the absolute value of the difference between the offset of the next layer rotation angle determined according to the current step angle in the radial feed direction of the turning tool and the offset of the current layer rotation angle in the radial feed direction of the turning tool is greater than the absolute value of the maximum feed amount, then the step angle is re-determined according to the maximum feed amount, and the rotation angle of the tool for the processing layer after the current layer is calculated based on the re-determined step angle.

3. The method for machining circular arc thread top according to claim 2, characterized in that: The method for re-determining the step angle according to the maximum feed amount is to calculate the step angle according to the following formula: Among them, Δα′ is the re-determined step angle, X 顶 R is the X-direction offset of the center of the tooth top arc relative to the origin O, 顶 is the radius of the tooth top arc, R 刀 is the tool tip radius, X n is the X-direction offset of the tool position relative to the origin O, ΔX max is the maximum feed amount, α n is the tool rotation angle of the nth layer, the nth layer is the current layer, the origin O is the intersection of the tooth top and the tooth profile symmetry axis, the radial retraction direction of the turning tool is the positive X direction, the radial feed direction of the turning tool is the negative X direction, the positive direction of the angular momentum when the spindle rotates counterclockwise is the positive Z direction, and the negative direction of the angular momentum when the spindle rotates counterclockwise is the negative Z direction.

4. The method for machining circular arc thread top according to claim 1, characterized in that: The tool tip radius must be greater than or equal to the minimum tool tip radius and less than or equal to the maximum tool tip radius; the tool maximum tool tip radius is determined based on the Z-direction offset of the tooth top arc center relative to the origin O, the tooth profile angle and the tooth top arc radius, the origin O is the intersection of the tooth top and the tooth profile symmetry axis, the radial retraction direction of the turning tool is the positive X direction, the radial feed direction of the turning tool is the negative X direction, the positive direction of the angular momentum when the spindle rotates counterclockwise is the positive Z direction, and the negative direction of the angular momentum when the spindle rotates counterclockwise is the negative Z direction; the tool minimum tool tip radius is the set multiple of the tool maximum tool tip radius, and the set multiple is greater than or equal to 1 / 3 and less than or equal to 1 / 2.

5. The method for machining circular arc thread top according to claim 4, characterized in that: The maximum tool nose radius is determined by the following formula: in, is the maximum tool tip radius, Z 顶 is the Z-direction offset of the center of the tooth top arc relative to the origin O, θ is the tooth profile angle, R 顶 is the radius of the tooth top arc.

6. The method for machining circular arc thread top according to claim 1, characterized in that: The method for calculating the offset coordinates of the tool when each layer moves is as follows: Calculate the X-direction offset X of the tool position relative to the origin O n , Z direction offset Z of tool position relative to origin O n , and determine the number of cutters per layer according to the tooth top width and tool width. When the number of cutters per layer is two, the offset coordinates of each cutter when each layer moves are (X n , Z n ) and (X n , -Z n ); When there are three cutting tools per layer, the offset coordinates of each tool when each layer moves are (X n , Z n )、(X n ,0) and (X n , -Z n ); where X n and Z n The calculation formula is: X n =X 顶 +(R 刀 +R 顶 )cos(α n ) Z n =Z 顶 -(R 刀 +R 顶 )sin(α n ) Among them, Z 顶 X is the Z-direction offset of the center of the tooth top arc relative to the origin O, 顶 R is the X-direction offset of the center of the tooth top arc relative to the origin O, 顶 is the radius of the tooth top arc, R 刀 is the tool tip radius, α n is the tool rotation angle of the nth layer, the origin O is the intersection of the tooth top and the tooth profile symmetry axis, the radial retraction direction of the turning tool is the positive X direction, the radial feed direction of the turning tool is the negative X direction, the positive direction of the angular momentum when the spindle rotates counterclockwise is the positive Z direction, and the negative direction of the angular momentum when the spindle rotates counterclockwise is the negative Z direction.

7. The method for machining circular arc thread top according to claim 6, characterized in that: Z 顶 and X 顶 Calculated according to the following formula: X 顶 =-R 顶 Among them, H is the tooth height.

8. The method for machining circular arc thread top according to claim 1, characterized in that: The tool rotates counterclockwise during machining.

9. A circular thread arc top processing device, comprising a processor, characterized in that: The processor is used to execute computer program instructions to implement the method for processing circular arc thread arc tops as described in any one of claims 1-8.

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