A machining process for transmission gears of double internal meshing planetary transmission mechanism of parameter-free gearbox

Abstract

The present invention discloses a transmission gear processing technology for a parameter-free gearbox double internal meshing planetary transmission mechanism, comprising the following steps: 1) importing the design drawings of the workpiece into the drawing software, and completing the drawing of the workpiece hot front wire cutting processing drawings; 2) placing the workpiece on the workbench of the medium-speed wire cutting machine, finding the center of the inner hole of the workpiece by setting the tool and using the three-point circle center determination method, setting it as the machine tool zero point, and processing the part according to the hot front wire cutting processing drawing; 3) after the processing is completed, selecting a tooth end face of the workpiece in the positive direction of Y and marking it; 4) importing the designed electronic version of the workpiece tooth profile drawing into the medium-speed wire cutting machine, and then placing the workpiece after heating on the workbench of the medium-speed wire cutting machine, and processing the part according to the electronic version of the workpiece tooth profile drawing. The present invention effectively solves the problem of post-heat deformation of the workpiece and the inability to ensure tooth profile accuracy by means of secondary wire cutting processing after heating and scanning and comparing the workpiece tooth profile drawing.

Description

Technical Field

[0001] The invention relates to the technical field of gearboxes, and in particular to a process for machining transmission gears of a double internal meshing planetary transmission mechanism of a parameter-free gearbox. Background Art

[0002] The gearbox double internal meshing planetary transmission mechanism gear is a new type of transmission gear structure of the transmission mechanism of the transmission. Usually use high-quality alloy structural steel with high strength, toughness and good hardenability.

[0003] When producing transmission gears, the gear blank is usually forged using a forging die, and then the transmission gear is finally produced through processes such as cutting, rolling, gear shaping, deburring, carburizing, quenching, shot blasting, grinding, gear grinding, and enhanced shot blasting.

[0004] During the processing of transmission gears, the gears are greatly deformed after carburizing and quenching. Therefore, the tooth profile processing after heat treatment is the key point. The processing method after heat treatment directly affects the common normal line of the gear and the accuracy of the tooth profile and tooth direction. In order to ensure the wider applicability of the design, conventional designers provide tooth profile drawings of transmission gears of double internal meshing planetary transmission mechanisms, but do not provide gear parameters. The processing unit can make adaptive adjustments to the dimensional parameters according to product requirements, which will make the existing hot pre-insertion, gear hobbing and hot post-grinding processes unusable, and the existing measurement methods cannot be used.

[0005] Therefore, a new processing and gear detection method is urgently needed to solve the above problems. Summary of the invention

[0006] The purpose of the present invention is to provide a transmission gear machining process for a parameter-free gearbox double internal meshing planetary transmission mechanism to solve the problems existing in the prior art.

[0007] The technical solution adopted to achieve the purpose of the present invention is as follows: a parameter-free gearbox double internal meshing planetary transmission mechanism transmission gear processing technology, comprising the following steps:

[0008] 1) Import the design drawings of the workpiece into the drawing software to complete the drawing of the workpiece hot front cutting processing drawings;

[0009] 2) Place the workpiece on the workbench of the medium-speed wire cutting machine, find the center of the inner hole of the workpiece by setting the tool and using the three-point circle centering method, set it as the machine tool zero point, and process the part according to the hot front wire cutting processing drawing;

[0010] 3) After the processing is completed, a tooth end face of the workpiece in the positive direction Y is selected and marked; wherein the two-dimensional structure of the workpiece is located in the plane XOY, and the axis of the workpiece is perpendicular to the plane XOY;

[0011] 4) Import the designed electronic workpiece tooth profile drawing into the medium-speed WEDM machine, and then place the heated workpiece on the workbench of the medium-speed WEDM machine. According to the tooth surface mark before heating in step 3), place the workpiece in the pre-heating position, use the three-point circle center determination method to find the center of the inner tooth of the workpiece, set it as the machine tool zero point, and process the part according to the electronic workpiece tooth profile drawing.

[0012] Furthermore, before step 1), the following steps are also included: the workpiece outer circle is enlarged by an allowance, a process ledge is reserved, and three threading holes are drilled on the end surface of the ledge.

[0013] Furthermore, in step 1), the drawing software uses CAD software, and uses an offset command to offset the inner and outer tooth shapes of the workpiece by 0.3 mm to reserve a post-heat processing allowance.

[0014] Furthermore, in step 2), a pressure plate is used to clamp the workpiece process bracket, and the threading hole and the outer toothed area are placed in the middle and suspended for threading processing.

[0015] Further, in step 4), the coordinates of two points on the tooth surface on both sides of the tooth marked by the electrode wire are recorded as (X1, Y1) and (X2, Y1), and the angles between these two points and the Y axis are recorded as α1 and α2, respectively. α1 and α2 are calculated using the following formula:

[0016] α=arctan(x / y)

[0017] In the formula, α is the angle between the point and the Y direction, x is the coordinate of the tool setting point in the X direction, and y is the coordinate of the tool setting point in the Y direction;

[0018] Then calculate the difference α3 between α1 and α2, and use the rotation command of the machine tool drawing software to rotate the electronic version of the tooth profile drawing to the angle corresponding to the workpiece placement.

[0019] Furthermore, after step 4), there are the following steps: spraying white developer on the toothed end face of the processed workpiece, and then scanning the workpiece with a 3D scanner to generate a 3D image; then converting the 3D tooth profile image into a 2D image, and comparing it with the designed tooth profile image to verify the processing accuracy.

[0020] The technical effect of the present invention is unquestionable. The present invention effectively solves the problem of workpiece deformation after heating and the inability to ensure tooth profile accuracy by means of secondary wire cutting processing after heating and scanning and comparing the tooth profile diagram of the workpiece. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 Schematic diagram of wire cutting processing of a workpiece according to the method of the present invention;

[0022] Figure 2 It is a schematic diagram of the post-heating tool setting angle correction method of the method of the present invention;

[0023] Figure 3 A schematic diagram of the tooth shape of a three-dimensional scan of a workpiece according to the method of the present invention;

[0024] Figure 4 A schematic diagram of the tooth shape of a workpiece converted from three dimensions to two dimensions according to the method of the present invention;

[0025] Figure 5 A two-dimensional tooth profile comparison schematic diagram of the method of the present invention;

[0026] Figure 6 This is a three-dimensional schematic diagram of the workpiece in Example 1;

[0027] Figure 7 This is a three-dimensional schematic diagram of the workpiece in Example 2;

[0028] Figure 8 This is a schematic diagram of three-dimensional scanning of a workpiece in Example 2;

[0029] Fig. 9 A schematic diagram showing a two-dimensional tooth profile comparison of a workpiece in Example 2;

[0030] Fig.10 This is a three-dimensional schematic diagram of the workpiece in Example 3;

[0031] Fig.11 This is a schematic diagram of the two-dimensional tooth shape comparison of the workpiece in Example 3. DETAILED DESCRIPTION

[0032] The present invention is further described below in conjunction with the embodiments, but it should not be understood that the above subject matter of the present invention is limited to the following embodiments. Without departing from the above technical ideas of the present invention, various substitutions and changes are made according to the common technical knowledge and customary means in the art, which should all be included in the protection scope of the present invention.

[0033] Embodiment 1:

[0034] This embodiment discloses a process for machining transmission gears of a double internal meshing planetary transmission mechanism of a parameter-free gearbox, see Figures 1 to 6 , including the following steps:

[0035] 1) Increase the allowance of the large outer circle of the workpiece, reserve a process sled, and drill 3 thread holes on the end face of the sled;

[0036] 2) See Figure 1 , import the design drawing of the workpiece into the CAD software, and use the offset command to offset the inner and outer tooth shapes of the workpiece by 0.3mm, leaving a post-heat processing allowance; press Figure 1 Leave three evenly distributed process shavings to divide the tooth shape into three independent areas; complete the drawing of the workpiece hot front cutting process;

[0037] 3) Place the workpiece on the workbench of the medium-speed wire cutting machine, clamp the workpiece process bracket with a pressure plate, place the wire threading hole and the external tooth area in the middle and suspend them for easy wire threading. Use the tool setting and three-point circle centering method to find the center of the inner hole of the workpiece, set it as the machine tool zero point, and process the parts according to the hot front wire cutting processing drawing;

[0038] 4) After the processing is completed, a tooth end face of the workpiece in the positive direction of Y is selected and marked to facilitate the alignment of the secondary wire cutting after heating; wherein the two-dimensional structure of the workpiece is located in the plane XOY, and the axis of the workpiece is perpendicular to the plane XOY;

[0039] 5) Import the designed electronic workpiece tooth profile into the medium-speed WEDM machine, and then place the heated workpiece on the workbench of the medium-speed WEDM machine. According to the tooth surface mark before heating in step 3), place the workpiece in the position before heating, use the three-point circle centering method to find the center of the workpiece inner tooth, set it as the machine tool zero point, and process the part according to the electronic workpiece tooth profile. For details, see Figure 2 , use the electrode wire to align the coordinates of the two points on the tooth surface on both sides of the marking tooth and record them as (X1, Y1) and (X2, Y1) respectively. The angles between these two points and the Y axis are recorded as α1 and α2 respectively. α1 and α2 are calculated using the following formula:

[0040] α=arctan(x / y)

[0041] In the formula, α is the angle between the point and the Y direction, x is the coordinate of the tool setting point in the X direction, and y is the coordinate of the tool setting point in the Y direction;

[0042] Then calculate the difference α3 between α1 and α2, and use the rotation command of the machine tool drawing software to rotate the electronic version of the tooth profile drawing to the angle corresponding to the workpiece placement.

[0043] 6) See Figure 3 , Figure 4 and Figure 5 , spray white developer on the toothed end face of the machined workpiece, and then use a 3D scanner to scan the workpiece to generate a 3D image; then convert the 3D tooth profile image into a 2D image and compare it with the designed tooth profile image to verify the machining accuracy. Figure 5 It can be seen that the scanned tooth shape of the workpiece completely coincides with the tooth shape on the drawing. Figure 6 Schematic diagram of a workpiece processed by the process described in this embodiment.

[0044] It is worth noting that the processing method of the transmission gear of the double internal meshing planetary transmission mechanism of the gearbox disclosed in this embodiment effectively solves the problem of post-heat deformation of the workpiece and the inability to ensure the tooth profile accuracy by means of secondary wire cutting processing after heat treatment and scanning and comparing the workpiece tooth profile diagram.

[0045] Embodiment 2:

[0046] This embodiment discloses a process for machining transmission gears of a parameter-free gearbox double internal meshing planetary transmission mechanism, comprising the following steps:

[0047] 1) Import the design drawing of the workpiece into the CAD drawing software, and use the offset command to offset the inner and outer tooth shapes of the workpiece by 0.3mm, leaving the post-heat processing allowance, and complete the drawing of the workpiece hot front line cutting processing drawing;

[0048] 2) Place the workpiece on the workbench of the medium-speed wire cutting machine, find the center of the inner hole of the workpiece by setting the tool and using the three-point circle centering method, set it as the machine tool zero point, and process the part according to the hot front wire cutting processing drawing;

[0049] 3) After the processing is completed, a tooth end face of the workpiece in the positive direction Y is selected and marked; wherein the two-dimensional structure of the workpiece is located in the plane XOY, and the axis of the workpiece is perpendicular to the plane XOY;

[0050] 4) Import the designed electronic workpiece tooth profile diagram into the medium-speed WEDM machine, and then place the heated workpiece on the workbench of the medium-speed WEDM machine. According to the tooth surface mark before heating in step 3), place the workpiece in the position before heating, and use the three-point circle centering method to find the center of the inner tooth of the workpiece, which is set as the machine tool zero point. Specifically, use the electrode wire to align the coordinates of the two points on the tooth surface on both sides of the marked tooth and record them as (X1, Y1) and (X2, Y1), respectively. The angles between these two points and the Y axis are recorded as α1 and α2, respectively. α1 and α2 are calculated using the following formulas:

[0051] α=arctan(x / y)

[0052] In the formula, α is the angle between the point and the Y direction, x is the coordinate of the tool setting point in the X direction, and y is the coordinate of the tool setting point in the Y direction;

[0053] Then calculate the difference α3 between α1 and α2, and use the rotation command of the machine tool drawing software to rotate the electronic version of the tooth profile drawing to the same angle as the workpiece. Process the parts according to the electronic version of the workpiece tooth profile drawing. Figure 7 , which is a three-dimensional image of the processed workpiece.

[0054] 5) Spray white developer on the toothed end surface of the machined workpiece, see Figure 8 , and then use a 3D scanner to scan the workpiece to generate a 3D graphic; then convert the 3D tooth profile into a 2D graphic and compare it with the designed tooth profile to verify the processing accuracy. The comparison results are as follows Fig. 9 As shown, Fig. 9 It can be seen that the scanned tooth shape of the workpiece completely coincides with the tooth shape on the drawing.

[0055] Embodiment 3:

[0056] The main steps of this embodiment are the same as those of embodiment 1, except that the processing of the inner teeth is reduced compared to embodiment 1. Fig.10 and Fig.11 , Fig.11 It can be seen that the scanned tooth shape of the workpiece completely coincides with the tooth shape on the drawing.

[0057] Embodiment 4:

[0058] This embodiment discloses a process for machining transmission gears of a parameter-free gearbox double internal meshing planetary transmission mechanism, comprising the following steps:

[0059] 1) Import the design drawings of the workpiece into the drawing software to complete the drawing of the workpiece hot front cutting processing drawings;

[0060] 2) Place the workpiece on the workbench of the medium-speed wire cutting machine, find the center of the inner hole of the workpiece by setting the tool and using the three-point circle centering method, set it as the machine tool zero point, and process the part according to the hot front wire cutting processing drawing;

[0061] 3) After the processing is completed, a tooth end face of the workpiece in the positive direction Y is selected and marked; wherein the two-dimensional structure of the workpiece is located in the plane XOY, and the axis of the workpiece is perpendicular to the plane XOY;

[0062] 4) Import the designed electronic workpiece tooth profile drawing into the medium-speed WEDM machine, and then place the heated workpiece on the workbench of the medium-speed WEDM machine. According to the tooth surface mark before heating in step 3), place the workpiece in the pre-heating position, use the three-point circle center determination method to find the center of the inner tooth of the workpiece, set it as the machine tool zero point, and process the part according to the electronic workpiece tooth profile drawing.

[0063] Embodiment 5:

[0064] The main steps of this embodiment are the same as those of embodiment 4. Furthermore, the following steps are included before step 1): the workpiece outer circle is enlarged to allow for a margin, a process ledge is reserved, and three threading holes are drilled on the end face of the ledge.

[0065] Embodiment 6:

[0066] The main steps of this embodiment are the same as those of embodiment 4. Furthermore, in step 1), the drawing software adopts CAD software, and uses an offset command to offset the inner and outer tooth shapes of the workpiece by 0.3 mm to reserve a post-heat processing allowance.

[0067] Embodiment 7:

[0068] The main steps of this embodiment are the same as those of Embodiment 5. Furthermore, in step 2), a pressure plate is used to clamp the workpiece process bracket, and the wire threading hole and the external toothed area are placed in the middle and suspended for wire threading processing.

[0069] Embodiment 8:

[0070] The main steps of this embodiment are the same as those of Embodiment 4. Further, in step 4), the coordinates of two points on the tooth surfaces on both sides of the tooth marked by the electrode wire are recorded as (X1, Y1) and (X2, Y1), respectively. The angles between these two points and the Y axis are recorded as α1 and α2, respectively. α1 and α2 are calculated using the following formula:

[0071] α=arctan(x / y)

[0072] In the formula, α is the angle between the point and the Y direction, x is the coordinate of the tool setting point in the X direction, and y is the coordinate of the tool setting point in the Y direction;

[0073] Then calculate the difference α3 between α1 and α2, and use the rotation command of the machine tool drawing software to rotate the electronic version of the tooth profile drawing to the angle corresponding to the workpiece placement.

[0074] Embodiment 9:

[0075] The main steps of this embodiment are the same as those of Embodiment 4. Furthermore, after step 4), there are the following steps: spraying white developer on the toothed end face of the processed workpiece, and then scanning the workpiece with a 3D scanner to generate a 3D graphic; then converting the 3D tooth profile diagram into a 2D diagram, and comparing it with the designed tooth profile diagram to verify the processing accuracy.

Claims

1. A process for machining transmission gears of a parameter-free gearbox with double internal meshing planetary transmission mechanism, characterized in that: The following steps are involved: Step 1) Import the design drawing of the workpiece into the drawing software to complete the drawing of the workpiece hot front cutting processing drawing; Step 2) Place the workpiece on the workbench of the medium-speed wire cutting machine, find the center of the inner hole of the workpiece by setting the tool and using the three-point circle centering method, set it as the machine tool zero point, and process the part according to the hot front wire cutting processing diagram; Step 3) After the processing is completed, select a tooth end face of the workpiece in the positive direction Y and mark it; wherein the two-dimensional structure of the workpiece is located in the plane XOY, and the axis of the workpiece is perpendicular to the plane XOY; Step 4) Import the designed electronic workpiece tooth profile drawing into the medium-speed wire cutting machine, then place the heated workpiece on the workbench of the medium-speed wire cutting machine, and place the workpiece according to the pre-heating tooth surface mark in step 3), find the center of the inner tooth of the workpiece by using the three-point circle center determination method, set it as the machine tool zero point, and process the part according to the electronic workpiece tooth profile drawing; Before step 1), the following steps are also included: the workpiece outer circle is increased in allowance, a process sled is reserved, and three threading holes are drilled on the end face of the sled; In step 1), the drawing software uses CAD software, and uses an offset command to offset the inner and outer tooth shapes of the workpiece by 0.3 mm to leave a post-heat processing allowance; In step 4), the coordinates of the two points on the tooth surface on both sides of the tooth marked by the electrode wire are recorded as (X1, Y1) and (X2, Y1), and the angles between these two points and the Y axis are recorded as α1 and α2, respectively. α1 and α2 are calculated using the following formula: α=arctan(x / y) In the formula, α is the angle between the point and the Y direction, x is the coordinate of the tool setting point in the X direction, and y is the coordinate of the tool setting point in the Y direction; Then calculate the difference α3 between α1 and α2, and use the rotation command of the machine tool drawing software to rotate the electronic version of the tooth profile drawing to the angle corresponding to the workpiece placement; After step 4), the following steps are also included: spraying white developer on the toothed end face of the processed workpiece, and then scanning the workpiece with a 3D scanner to generate a 3D image; then converting the 3D tooth profile image into a 2D image, and comparing it with the designed tooth profile image to verify the processing accuracy.

2. The process for machining transmission gears of a parameter-free gearbox double internal meshing planetary transmission mechanism according to claim 1, characterized in that: In step 2), the workpiece process bracket is clamped with a pressure plate, and the threading hole and the outer toothed area are placed in the middle and suspended for threading processing.

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