Large-pitch arc thread profiling machining method and device

Abstract

The invention relates to a large-pitch arc thread profiling machining method and device, and belongs to the technical field of thread machining. The method comprises the following steps: firstly, carrying out rough machining from a first position to a second position by utilizing an arc turning tool in the radial feeding direction of the turning tool, and then taking the second position as a starting point of the circle center position of the arc turning tool during tooth side machining; and the position of a tool nose of the tool is controlled to be spaced by the required feeding amount in the radial feeding direction and spaced by the product of the required feeding amount and the half thread angle cosine value in the axial direction, layered machining is conducted on the tooth side according to the tool nose offset coordinates of all layers, and after the tooth side machining is completed, the arc turning tool is used for machining the arc tooth bottom. Therefore, the arc turning tool can be used for machining the tooth side, only one turning tool needs to be used for machining the tooth # imgabs0 # and the tooth side of the arc thread, tool changing and tool setting in the machining process are not needed, the machining efficiency is improved, and the problem of poor precision caused by tool setting is solved.

Description

Technical Field

[0001] The invention relates to a large pitch circular arc thread profiling method and device, belonging to the technical field of thread processing. 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, manufacturing, structural strength, and fatigue resistance. The Chinese utility model patent with the 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 thread and the external thread are in surface contact and the force is uniform. 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 major thread diameters of 42 and 48, and pitches of 6.35 and 8.5 respectively. The Chinese patent with authorization announcement number CN116877555B discloses a double-ended stud for connecting the root of a wind turbine blade and a processing method thereof. The external thread of the threaded section of the double-ended stud is a circular arc thread. The nominal diameter of the circular arc thread dnominal = 36mm~40mm, the pitch of the circular arc thread Pr = (0.153~0.192)dnominal, the tooth height of the circular arc thread hr = (0.37~0.44)Pr, and the minor diameter of the circular arc thread d1r = dnominal-0.8746Pr.

[0003] As can be seen from the above, the tooth profile of the arc thread is a symmetrical structure, including two symmetrical tooth tops, tooth sides composed of edge lines and an arc tooth bottom. In traditional technology, trapezoidal turning tools are generally used to machine the tooth sides of arc threads, and arc turning tools are used to machine the arc teeth of arc threads. The tool needs to be changed during the processing. There may be errors in the tool alignment between the arc turning tool and the trapezoidal turning tool, resulting in obvious tool marks on the tooth profile surface. And when using the trapezoidal turning tool to process the tooth side, since the tooth profile angle accuracy of the tooth side depends on the clamping accuracy of the trapezoidal tool, in order to ensure the tooth side processing accuracy, it takes a long time to align the tool, resulting in low arc thread processing efficiency. Summary of the invention

[0004] The purpose of the present invention is to provide a large pitch arc thread profiling processing method and device to solve the problem that the current large pitch arc thread processing using an arc turning tool requires the tool to be changed midway to process the tooth side, resulting in obvious tool marks, low processing efficiency and poor precision.

[0005] In order to solve the above technical problems, the present invention provides a large pitch circular arc thread profiling processing method, the processing method comprises:

[0006] 1) machining from a first position to a second position along the radial feed direction of the turning tool using an arc turning tool, wherein the first position is the center position of the tool arc when the intersection of the tool arc radius and the tooth side and tooth top axes are tangent in the tooth side direction, and the second position is the center position of the tool arc when the first position is translated to the point where the tool arc is tangent to the tooth top axis;

[0007] 2) Using the second position as the starting point of the arc turning tool center position when machining the tooth side, controlling the tool tip position in the radial feed direction to be spaced by the required feed amount and in the axial direction to be spaced by the product of the required feed amount and half the cosine value of the tooth profile angle, and using the second position to determine the tool tip offset coordinates of each layer when machining the tooth side, and performing layered machining on the tooth side according to the tool tip offset coordinates of each layer, with the axial direction being the direction of the lathe rotation axis;

[0008] 3) After the tooth side processing is completed, use the arc turning tool to process the arc tooth bottom.

[0009] Furthermore, the tool tip radius of the arc turning tool needs to meet the following conditions:

[0010]

[0011] Among them, R 底 is the tooth bottom radius, R 刀 W is the tool tip radius of the arc turning tool, 顶 is the tooth top width, and θ is the tooth profile angle.

[0012] Furthermore, each cut in step 1) is processed according to a set feed amount, and the set feed amount is determined according to the maximum feed amount and the processing depth. The processing depth is the distance between the first position and the second position, and the distance is the distance in the radial feed direction of the turning tool. The calculation formula used is:

[0013]

[0014] Where X A is the processing depth, R 刀 is the tool nose radius of the arc turning tool, and θ is the tooth angle.

[0015] Furthermore, in step 1), the processing method of cutting each layer is adopted, and each layer has two cutters, and the offset coordinates of the tool tip position of each layer relative to the origin O are (X n , Z i ) and (X n , -Z i ), X n Indicates the tool tip position offset relative to the origin O in the radial feed direction of the turning tool during the nth layer processing, Z iIt indicates the tool tip position offset relative to the origin O in the direction of the machine tool rotation axis during each layer processing. The origin O is the intersection of the tooth top and the tooth profile symmetry axis. n and Z i The calculation formula used is:

[0016] X n =nΔX 设定

[0017]

[0018] Where R 刀 W is the tool tip radius of the arc turning tool, 顶 is the tooth crest width.

[0019] Furthermore, the required feed amount in step 2) is determined according to the maximum feed amount, the required feed amount is less than or equal to the maximum feed amount, and the determined maximum feed amount is:

[0020]

[0021] Where ΔX 牙侧max is the maximum feed amount along the radial feed direction of the turning tool during tooth side machining, R z is the required roughness, R 刀 is the tool nose radius of the arc turning tool, and θ is the tooth angle.

[0022] Furthermore, the required feed amount is:

[0023]

[0024] Where ΔX 牙侧 is the required feed amount, Indicates rounding up, H 侧 is the tooth side height, and m is the number of layers required for machining the tooth side.

[0025] Furthermore, in step 2), the tooth side is processed in layers according to the tool tip offset coordinates of each layer, and the tool side is processed by a tool-driving method for each layer. Each layer has two tools, and the tool tip offset coordinates of each layer relative to the origin O are (X j , Z j ) and (X j , -Z j ), X j It represents the offset of the turning tool in the radial feed direction relative to the origin O when machining the jth layer of the tooth side, Z j It indicates the offset relative to the origin O in the direction of the machine tool rotation axis when machining the jth layer of the tooth side. The origin O is the intersection of the tooth top and the tooth profile symmetry axis. j and Z j The calculation formula used is:

[0026] X j =X A +jΔX 牙侧

[0027]

[0028] Where X A is the processing depth, ΔX 牙侧 is the required feed amount and θ is the tooth angle.

[0029] Furthermore, in step 3), the arc tooth bottom is processed according to the tool rotation angle and offset coordinates of each cut when the arc turning tool moves according to the set step angle, until the tool rotation angle is Rotate to θ is the tooth angle.

[0030] Furthermore, the step angle set in step 3) is determined according to the tool tip radius, tooth bottom arc radius and surface roughness of the tool, and the calculation formula used is:

[0031]

[0032] Among them, Δβ is the set step angle, R 刀 is the tool tip radius, R 底 R is the radius of the tooth bottom arc, Z is the surface roughness.

[0033] The present invention also provides a large pitch circular arc thread profiling processing device, comprising a processor, wherein the processor is used to execute computer program instructions to implement the large pitch circular arc thread profiling processing method.

[0034] The beneficial effects of the present invention are as follows: as a pioneering invention, the present invention first uses an arc turning tool to perform rough machining along the radial feed direction of the turning tool, so that the center of the arc of the arc turning tool is machined from a first position to a second position, and then the second position is used as the starting point of the center position of the arc turning tool during tooth side machining, and the tool tip position is controlled to be spaced at intervals of the required feed amount in the radial feed direction and at intervals of the product of the required feed amount and half the cosine value of the tooth profile angle in the axial direction, and the second position is used to determine the tool tip offset coordinates of each layer when machining the tooth side, and the tooth side is layered according to the tool tip offset coordinates of each layer; and after the tooth side machining is completed, the arc tooth bottom is machined using the arc turning tool. It can be seen that the present invention can use the arc turning tool to realize the machining of the tooth side, so that the tooth of the arc thread can be machined Only one turning tool is needed for machining the tooth side, and there is no need to change or adjust the tool during machining. This not only improves the machining efficiency, but also avoids the problem of poor precision caused by tool adjustment. BRIEF DESCRIPTION OF THE DRAWINGS

[0035] Figure 1 It is a flow chart of the large pitch circular arc thread profiling method of the present invention;

[0036] Figure 2 This is a schematic diagram of the principle of selecting the tool tip radius during the large pitch arc thread profiling process of the present invention;

[0037] Figure 3 It is a schematic diagram of the first position and the second position during the processing of the large pitch arc thread of the present invention;

[0038] Figure 4 It is a schematic diagram of the tool position for rough machining of large pitch circular arc threads of the present invention;

[0039] Figure 5 It is a schematic diagram of the tool position for machining the flank of a large pitch circular arc thread of the present invention;

[0040] Figure 6 Schematic diagram of the relationship between the roughness and the tool tip radius when the large pitch arc thread of the present invention is processed on the tooth side;

[0041] Figure 7 It is a calculation principle diagram of the maximum feed amount when the large pitch arc thread of the present invention is processed on the tooth side;

[0042] Figure 8 This is a calculation principle diagram of the large pitch arc thread of the present invention when performing tooth side layered feed processing;

[0043] Fig. 9 It is a calculation principle diagram of the step angle when the large pitch arc thread of the present invention is processed at the bottom of the thread;

[0044] Fig.10 It is a schematic diagram of the processing principle of the large pitch arc thread bottom processing of the present invention;

[0045] Fig.11 It is a schematic diagram of the tool position for machining the tooth bottom of a large pitch circular arc thread according to the present invention. DETAILED DESCRIPTION

[0046] The specific implementation of the present invention will be further described below in conjunction with the accompanying drawings.

[0047] Embodiment of large pitch arc thread profiling method

[0048] The present invention firstly uses an arc turning tool to perform rough machining along the radial feed direction of the turning tool, from the first position to the second position, and then uses the second position as the starting point of the arc turning tool center position when machining the tooth side, controls the tool tip position to be spaced by the required feed amount in the radial feed direction and by the product of the required feed amount and the cosine value of half the tooth profile angle in the axial direction, and uses the second position to determine the tool tip offset coordinates of each layer when machining the tooth side, and performs layered machining on the tooth side according to the tool tip offset coordinates of each layer; and after the tooth side machining is completed, uses the arc turning tool to machine the arc tooth bottom. Because during machining, when the arc turning tool gradually moves from the second position to the third position (i.e., O2), the arc surface of the arc turning tool is tangent to the tooth side, and when machining the bottom arc, the arc surface of the arc turning tool is tangent to the tooth bottom arc, so the entire machining process can be considered as a profiling machining process.

[0049] The implementation process of this method is as follows Figure 1 shown.

[0050] In this embodiment, a nut with a large pitch arc thread is used as the object to be processed, wherein the arc thread tooth angle is θ and the tooth bottom radius is R 底 , tooth height is H, tooth top width is W 顶 , the maximum height of the profile, i.e. the roughness, is R Z , tooth bottom radius is R 底 , the radial retraction direction of the turning tool is taken as the positive direction of the X-axis, that is, +X axis, the radial feed direction of the turning tool is taken as the negative direction of the X-axis, that is, -X axis, the direction of the machine tool rotation axis (also called spindle) is taken as the Z axis, the negative direction of the angular momentum when the spindle rotates counterclockwise is -Z axis, and the positive direction of the angular momentum when the spindle rotates clockwise is +Z axis, the intersection of the tooth top and the tooth profile symmetry axis is taken as the coordinate origin O, and the center of the tooth bottom arc is O 底 The X-direction offset of the center of the arc at the bottom of the tooth relative to point O is X 底 The offset of the center of the arc at the bottom of the tooth relative to point O in the Z direction is Z 底 , the processing of the present invention is described in detail below.

[0051] 1. Determine the tool parameters.

[0052] Since the present embodiment needs to use an arc turning tool to process the entire arc thread, considering the processing efficiency, it is ensured that each layer can be processed with two cuts, such as Figure 2 As shown, the tool tip radius of the arc turning tool in this embodiment needs to meet the following conditions:

[0053]

[0054] Among them, R 底 is the tooth bottom radius, R 刀 W is the tool tip radius of the arc turning tool, 顶 is the tooth crest width.

[0055] As another implementation method, each layer can also be completed with multiple cutters. For example, each layer can be completed with k cutters. In this case, the tool tip radius of the arc turning tool needs to meet the following conditions:

[0056]

[0057] Considering the processing efficiency, each layer has a maximum of 3 cuts. If 3 cuts are used, the tool tip radius of the arc turning tool must meet the following conditions:

[0058]

[0059] 2. Use arc turning tool for rough machining.

[0060] 1) Determine the two positions during roughing

[0061] Based on the above processing parameters, determine the coordinate Z of the intersection of the tooth profile angle and the tooth top axis. 顶 , Z 顶 is the tooth crest width W 顶 half of Figure 3 As shown, first make the tool arc radius R 刀 With Z 顶 Tangent to the tooth side, calculate the center of the tool arc at this time and record it as O2, which is the second position, then translate the determined tool arc center O2 along the X-axis direction until the top arc is just tangent to the top axis, and calculate the tool center at this time and record it as O1, which is the first position. Move the determined tool arc center O2 along the tooth side until it is just tangent to the tooth bottom arc, and calculate the tool center at this time and record it as O3, O3 is the stop position of the tool arc center during tooth side machining, where the distance between O2 and O3 in the radial feed direction of the turning tool is the tooth side height H 侧 The rough machining can be completed by using the arc turning tool to machine the tool center from the first position to the second position along the radial feed direction of the turning tool (negative direction of the X axis).

[0062] 2) Determine the feed amount during rough machining

[0063] In this embodiment, the rough machining process is to machine from the first position to the second position along the radial feed direction of the turning tool according to the set feed amount, wherein the feed amount of each cut is equal to the set feed amount. The set feed amount is determined based on the maximum feed amount and the machining depth, and the machining depth is the distance between the first position and the second position, which is the distance in the radial feed direction of the turning tool. The specific determination process is as follows:

[0064] According to the tool and processing experience, determine an initial maximum feed amount, and determine the number of roughing feed layers l based on the initial maximum feed amount:

[0065]

[0066] Where X A is the processing depth, Indicates rounding up, such as Figure 4 As shown, the processing depth here is the distance from O1 and O2 in the X-axis direction, which can be calculated using the tooth angle and tool arc radius. The specific calculation formula is:

[0067]

[0068] The set feed amount is determined according to the number of feeds, so that the feed amount of each cut during processing is the same. The specific calculation of the set feed amount is:

[0069]

[0070] During the entire rough machining process, the tool tip of each layer moves along the X direction, and the offset in the Z direction is equal. The tool tip position offset of each layer relative to the origin O is Z. i , Z i for:

[0071]

[0072] The offset X of the tool tip position relative to the origin O in the X direction when the tool is machining the nth layer n for:

[0073] X n =nΔX 设定

[0074] The origin O is the intersection of the tooth top and the tooth profile symmetry axis. During rough machining, the method of chasing the cutter on each layer is adopted. Each layer has two cutters, and the machining offsets of each cutter on each layer are (X n , Z i ) and (X n , -Z i ). Processing process: First, (X1, Z i ) is used as the offset to process the first cut, with (X1, -Z i ) is used as the offset to process the second cut, thus completing the first layer processing; then (X2, Z i ) as the offset to process the third cut, and then (X2, -Z i ) is the fourth cut for offset processing; repeat this process until the first layer is completed, that is, the offset (X l , Z i ) and (X l , -Z i ) processing.

[0075] This process does not perform tooth profile profiling or top arc processing, but only removes a large amount of material with the maximum feed amount. Therefore, this process can be recorded as the rough processing process of arc thread.

[0076] 3. Perform tooth side processing.

[0077] Since the tool is not changed when machining the tooth side, the same arc turning tool as used for the tooth top machining is still used, but the side of the arc turning tool is an arc surface, which is tangent to the edge line of the tooth angle to be machined, so the tooth angle needs to be profiled. During the profiling process, it is necessary to ensure the roughness of the tooth angle and establish the relationship between the shape of the arc turning tool and the tooth angle. The present invention controls the position of the tool tip in the radial feed direction with the required feed amount as the interval, and in the axial direction with the product of the required feed amount and half the cosine value of the tooth angle as the interval, and uses the second position to determine the tool tip offset coordinates of each layer when machining the tooth side, and performs layered processing on the tooth side according to the tool tip offset coordinates of each layer.

[0078] 1) Determine the maximum feed amount during tooth side machining and use this to determine the feed amount required for each cut

[0079] like Figure 5 As shown, the tooth side height H is calculated based on the tooth height, tooth bottom radius and tooth profile angle. 侧 , H 侧 The calculation formula is:

[0080]

[0081] According to the required roughness R Z Calculate the maximum feed amount ΔX required for machining the tooth side 牙侧max ,like Figure 6 As shown, the roughness R Z The following relationship exists with the tool arc radius:

[0082] R z =R 刀 -AB

[0083]

[0084] ΔL=2OB

[0085] like Figure 7 As shown in the figure, considering the tooth profile angle θ, the maximum feed amount ΔX in the X direction during tooth side machining is 牙侧max = ΔL multiplied by Based on the ΔL calculated previously, ΔX 牙侧max The calculation formula is:

[0086]

[0087] ΔX 牙侧maxThe number of layers m required for processing the tooth side is calculated as the maximum feed amount in the X direction during tooth side processing. The feed amount required for processing the tooth side is calculated based on the required number of layers and tooth side height to ensure that the feed amount of each cut is the same when processing the tooth side. The calculation formulas for the number of layers m required for processing the tooth side and the feed amount required for processing the tooth side are:

[0088]

[0089] As another implementation method, m can also be increased on this basis. The more it increases, the more processing layers are required.

[0090] 2) Process the tooth side in layers at equal intervals according to the required feed amount

[0091] The processing of each layer on the tooth side is still carried out in layers by the way of chasing the cutter, and each layer has two cuts, such as Figure 8 As shown, the machining offset of each tool in each layer is (X j , Z j ) and (X j , -Z j ), X j It indicates the offset in the radial feed direction of the turning tool when machining the jth layer of the tooth side, Z j Indicates the offset in the direction of the machine tool rotation axis when machining the jth layer of the tooth side, X j and Z j The calculation formula used is:

[0092] X j =X A +jΔX 牙侧

[0093]

[0094] If the tool is fed from right to left during machining, first calculate the Z-axis offset Z1 and X-axis offset X1 of the first tool according to the formula. When machining the first layer, first use (X1, Z1) as the offset to machine the first tool, and then use (X1, -Z1) as the offset to machine the last tool. At this point, the first layer is machined. Then use ΔX 牙侧 The X-axis steps forward, processing the second and third layers until the mth layer is completed. At this time, mΔX 牙测 Equal to H 侧 .

[0095] Through the above process, the tooth side processing can be completed using the arc turning tool.

[0096] 4. Perform arc processing on the tooth bottom.

[0097] 1) Determine the step angle when machining the tooth bottom arc based on the surface roughness

[0098] like Fig. 9 As shown, O 刀 is the center of the current tool tip arc, O′ 刀 is the center of the arc of the tool tip of the next cut. The step angle between two adjacent cuts is Δβ. According to the cosine theorem, the calculation formula of Δβ is as follows:

[0099]

[0100] Among them, R z The surface roughness is the surface roughness. According to the surface roughness, the arc radius of the tooth bottom and the tool tip radius, the step angle suitable for the arc tooth top can be calculated.

[0101] 2) Calculate the offset coordinates of each cut when the tool moves

[0102] First, calculate the tool rotation angle of each cut. The tool rotation angle of each cut is equal to the tool rotation angle of the previous cut minus the step angle of the current layer, β n =β n-1 -Δβ,β n is the tool rotation angle of the nth tool, β n-1 is the tool rotation angle of the n-1th tool,

[0103] According to the tool tip radius, tooth profile parameters and the rotation angle of each layer of tool, the offset coordinates (X n , Z n ); tooth profile parameters include tooth bottom arc radius, tooth height and tooth profile angle. Fig.10 As shown in Figure 2, for any tool n when machining the tooth bottom arc, the tool rotation angle is β n , the X-direction offset of the tool position (i.e. the center of the tool tip arc) relative to the origin O n The calculation formula is:

[0104] X n =HR 底 +(R 底 -R 刀 )cos(β n )

[0105] The Z offset of the tool position relative to the origin O n The calculation formula is:

[0106] Z n =(R 底 -R 刀 )sin(β n )

[0107] According to the calculated offset coordinates (X n , Z n) and the corresponding rotation angle β n Process the arc tooth bottom until the tool rotation angle reaches

[0108] like Fig.11 As shown, in this embodiment, the feed direction is in an arc shape from right to left. First, the tool rotation angle β1 of the first cut is calculated: β1 = β0-Δβ, The tool offset coordinates (X1, Z1) of the first cut are calculated based on β1, and (X1, Z1) is used as the offset coordinates to perform spiral processing according to the rotation angle of β1; then the tool rotation angle β2 of the second cut is calculated: β2 = β1-Δβ, and the offset coordinates (X2, Z2) of the second cut are calculated based on β2, and (X2, Z2) is used as the offset coordinates to perform spiral processing according to the rotation angle of β2, and so on until the processing is completed. At this point, the tooth bottom arc processing is completed.

[0109] Preferably, taking into account the deformation of the tool guide rod, the tool rotates counterclockwise when the tool is moving, so that there is always material to support the tool at the current processing position, effectively reducing the tool vibration phenomenon.

[0110] Embodiment of large pitch circular arc thread profiling device

[0111] A large pitch arc thread profiling device of the present invention can be used to execute computer program instructions to implement the large pitch arc thread profiling method in the above method embodiment. The device can be a CNC lathe for processing threads, and the CNC lathe executes computer program instructions to control the arc turning tool to process the arc thread tooth side.

Claims

1. A method for profiling a large pitch circular arc thread, characterized in that: The processing method includes: 1) machining from a first position to a second position along the radial feed direction of the turning tool using an arc turning tool, wherein the first position is the center position of the tool arc when the intersection of the tool arc radius and the tooth side and tooth top axes are tangent in the tooth side direction, and the second position is the center position of the tool arc when the first position is translated to the point where the tool arc is tangent to the tooth top axis; 2) Using the second position as the starting point of the arc turning tool center position when machining the tooth side, controlling the tool tip position in the radial feed direction to be spaced by the required feed amount and in the axial direction to be spaced by the product of the required feed amount and half the cosine value of the tooth profile angle, and using the second position to determine the tool tip offset coordinates of each layer when machining the tooth side, and performing layered machining on the tooth side according to the tool tip offset coordinates of each layer, with the axial direction being the direction of the lathe rotation axis; 3) After the tooth side processing is completed, use the arc turning tool to process the arc tooth bottom.

2. The large pitch circular arc thread profiling method according to claim 1, characterized in that: The tool tip radius of the arc turning tool needs to meet the following conditions: Among them, R 底 is the tooth bottom radius, R 刀 W is the tool tip radius of the arc turning tool, 顶 is the tooth top width, and θ is the tooth profile angle.

3. The large pitch circular arc thread profiling method according to claim 1, characterized in that: In the step 1), each cut is processed according to the set feed amount, which is determined according to the maximum feed amount and the processing depth. The processing depth is the distance between the first position and the second position, which is the distance in the radial feed direction of the turning tool. The calculation formula used is: Where X A is the processing depth, R 刀 is the tool nose radius of the arc turning tool, and θ is the tooth angle.

4. The large pitch circular arc thread profiling method according to claim 3, characterized in that: In the step 1), the processing method of cutting each layer is adopted, and each layer has two cutters. The offset coordinates of the tool tip position of each layer relative to the origin O are (X n , Z i ) and (X n , -Z i ), X n Indicates the tool tip position offset relative to the origin O in the radial feed direction of the turning tool during the nth layer processing, Z i It indicates the tool tip position offset relative to the origin O in the direction of the machine tool rotation axis during each layer processing. The origin O is the intersection of the tooth top and the tooth profile symmetry axis. n and Z i The calculation formula used is: X n =nΔX 设定 Where R 刀 W is the tool tip radius of the arc turning tool, 顶 is the tooth crest width.

5. The large pitch circular arc thread profiling method according to claim 1 or 2, characterized in that: The required feed amount in step 2) is determined according to the maximum feed amount. The required feed amount is less than or equal to the maximum feed amount. The determined maximum feed amount is: Where ΔX 牙侧max is the maximum feed amount along the radial feed direction of the turning tool during tooth side machining, R z is the required roughness, R 刀 is the tool nose radius of the arc turning tool, and θ is the tooth angle.

6. The method for profiling a large pitch circular arc thread according to claim 5, characterized in that: The required feed amount is: Where ΔX 牙侧 is the required feed amount, Indicates rounding up, H 侧 is the tooth side height, and m is the number of layers required for machining the tooth side.

7. The large pitch circular arc thread profiling method according to claim 1 or 2, characterized in that: The step 2) performs layered processing on the tooth side according to the tool tip offset coordinates of each layer. The tool tip offset coordinates of each layer relative to the origin O are respectively (X j , Z j ) and (X j , -Z j ), X j It indicates the offset of the turning tool in the radial feed direction relative to the origin O when machining the jth layer of the tooth side, Z j It indicates the offset relative to the origin O in the direction of the machine tool rotation axis when machining the jth layer of the tooth side. The origin O is the intersection of the tooth top and the tooth profile symmetry axis. j and Z j The calculation formula used is: X j =X A +jΔX 牙侧 Where X A is the processing depth, ΔX 牙侧 is the required feed amount and θ is the tooth angle.

8. The large pitch circular arc thread profiling method according to claim 1 or 2, characterized in that: In step 3), the arc tooth bottom is processed according to the tool rotation angle and offset coordinates of each cut when the arc turning tool moves according to the set step angle, until the tool rotation angle is Rotate to θ is the tooth angle.

9. The method for profiling a large pitch circular arc thread according to claim 8, characterized in that: The step angle set in step 3) is determined according to the tool tip radius, tooth bottom arc radius and surface roughness of the tool, and the calculation formula used is: Among them, Δβ is the set step angle, R 刀 is the tool tip radius, R 底 R is the radius of the tooth bottom arc, Z is the surface roughness.

10. A large pitch arc thread profiling device, comprising a processor, characterized in that: The processor is used to execute computer program instructions to implement the large pitch circular arc thread profiling method as described in any one of claims 1-9.

Images