A guide rail type machine tool for processing an angle profiled toroidal worm and a processing method thereof

Abstract

This invention relates to a guideway-type machine tool and its machining method for machining angle-modified toroidal worm gears. The guideway-type machine tool includes a machine body, on which a horizontally movable tool setting module is mounted. The tool setting module is connected to a tool holder module capable of circular offset and vertical movement. The tool holder module is connected to a grinding wheel module capable of forward and backward movement and flipping. The machine body also includes a clamping module for holding the worm gear blank. The grinding wheel module is positioned on the side of the worm gear blank. The tool holder module moves along a helical path to achieve angle-modified machining of the worm gear blank. Compared with existing technologies, this invention uses an axis deflection angle Δ∑ to control the slider movement, causing the tool holder to offset to the corresponding machining position, thus achieving the desired angle modification parameter p when the grinding wheel is machining the toroidal worm gear. d The adjustment allows the tool holder to move along a spiral path to achieve the angular shaping of the toroidal worm gear, and also to adjust the grinding wheel tilt angle β, thereby effectively improving machining efficiency while ensuring machining accuracy and reliability.

Description

Technical Field

[0001] This invention relates to the field of toroidal worm gear machining technology, and in particular to a guide rail machine tool for machining angle-modified toroidal worm gears and its machining method. Background Technology

[0002] Compared to cylindrical worm gear drives, toroidal worm gear drives offer advantages such as higher load-bearing capacity, smaller size, and higher transmission efficiency, and are currently widely used in high-speed, heavy-load applications. However, due to their unique bi-line contact method, toroidal worm gear pairs require high meshing quality, necessitating modifications to the worm tooth surface structure to optimize the contact area and thus improve macroscopic meshing quality. Therefore, tooth surface modification is often required during the production of toroidal worm gears.

[0003] Chinese patent CN102310347A proposes a seven-axis CNC grinding machine for a double-conical double-enveloping toroidal worm gear. This solution completes the machining of the toroidal worm gear through seven-axis linkage and is equipped with a grinding wheel dresser, solving the problem of easy wear of the grinding wheel head requiring frequent replacement and tool resetting. However, its grinding wheel angle controller adjusts the inclination angle β of the grinding wheel's production surface, aiming only to machine toroidal worm gears with different numbers of heads. This seven-axis CNC grinding machine cannot control the angle of the tool holder, thus failing to achieve the angle-modified machining of the worm gear's helical surface. Chinese patent CN101745703B proposes a manufacturing method for an angle-modified double-circular toroidal double-enveloping toroidal worm gear pair, but its tool holder needs to achieve helical motion, and it does not provide a specific means of machining the angle-modified toroidal worm gear.

[0004] Currently, in the field of toroidal worm gear machining, most machine tools achieve center distance modification by changing the longitudinal feed; and by controlling the transmission ratio by changing the workpiece speed and the grinding wheel speed to achieve transmission ratio modification. It can be said that existing technology lacks research on dedicated machine tools for machining toroidal worm gears with angle modification capabilities, making it impossible to efficiently and reliably manufacture angle-modified toroidal worm gears. Summary of the Invention

[0005] The purpose of this invention is to overcome the defects of the prior art by providing a guide rail machine tool and its machining method for machining angle-modified toroidal worm gears, which can effectively improve machining efficiency and ensure machining accuracy and reliability.

[0006] The objective of this invention can be achieved through the following technical solution: a guide rail machine tool for machining angle-trimmed toroidal worm gears, comprising a machine tool body, a horizontally movable tool setting module on the machine tool body, a tool holder module connected to the tool setting module capable of circular arc offset movement and vertical movement, a grinding wheel module connected to the tool holder module capable of forward and backward movement and flipping movement, a clamping module for clamping worm gear blanks on the machine tool body, the grinding wheel module being disposed on the side of the worm gear blanks, and the tool holder module moving along a helical path to achieve angle trimming machining of the worm gear blanks.

[0007] Furthermore, the tool setting module includes a horizontal guide rail disposed at the bottom of the machine tool body, a horizontal slide plate mounted on the horizontal guide rail, and the tool holder module slidably connected above the horizontal slide plate.

[0008] Furthermore, slide guide rails for connecting the tool holder module are provided on both sides of the top of the horizontal slide.

[0009] Furthermore, the tool holder module includes an arc guide rail, on which a slider is mounted. By changing the position of the slider, the tool holder is tilted to adjust the angle between the tool holder's rotation axis and the worm gear axis.

[0010] The slider is connected to a rotary worktable that can move up and down, which is used to adjust the shaping parameters of the grinding wheel module when machining toroidal worm gears.

[0011] Furthermore, a lifting device is connected to the bottom of the rotary table.

[0012] Furthermore, the grinding wheel module includes a longitudinal slide connected to the top of the rotary table, and a connecting cylinder connected to the grinding wheel is installed on the longitudinal slide. The grinding wheel tilt angle is adjusted by rotating the connecting cylinder.

[0013] Furthermore, a grinding head and a motor for driving the grinding wheel are respectively connected to both ends of the connecting cylinder.

[0014] Furthermore, the clamping module includes a tailstock and a spindle box that are arranged opposite each other and have an adjustable spacing. The tailstock is connected to a ejector pin, and a worm gear blank is clamped between the ejector pin and the spindle box.

[0015] Furthermore, the tailstock is connected to an axial slide, which is mounted on an axial guide rail, which is located at the top of the machine tool body.

[0016] Furthermore, one end of the tailstock is connected to an adjustment handle for adjusting the distance between the tailstock and the spindle box.

[0017] A machining method for a guideway-type machine tool for machining angle-modified toroidal worm gears includes the following steps:

[0018] S1. The worm blank is clamped in the corresponding position of the machine tool body using the clamping module and rotates.

[0019] S2. Control the tool setting module to move to the side position of the worm blank, and control the tool holder module to move closer to the worm blank.

[0020] S3. According to the set axis deflection angle Δ∑, control the slider in the tool holder module to move along the arc guide rail, causing the tool holder to tilt and shift to the corresponding processing position;

[0021] The connecting cylinder inside the control tool holder module rotates to adjust the grinding wheel tilt angle β, which is used to process toroidal worm gears with different numbers of threads;

[0022] Based on the worm gear blank rotation angle φ, the height Δd of the rotary table inside the tool holder module is controlled to adjust the dressing parameter p of the grinding wheel when machining the toroidal worm gear. d =Δd / φ, which causes the tool holder to move along the helical path to achieve the angular shaping of the toroidal worm.

[0023] Compared with the prior art, the present invention has the following advantages:

[0024] I. This invention features a horizontally movable tool setting module mounted on the machine tool body. This module is connected to a tool holder module capable of circular offset and vertical movement. The tool holder module is connected to a grinding wheel module capable of forward and backward movement and flipping. A clamping module for holding the worm gear blank is also provided on the machine tool body. By controlling and adjusting the working states of the tool setting module, tool holder module, and grinding wheel module, the tool holder module can move along a helical path to achieve angular shaping of the worm gear blank. This effectively improves machining efficiency, ensures machining accuracy, and enhances the meshing quality of the worm gear pair.

[0025] II. This invention controls the movement of the slider by using the axis deflection angle Δ∑, causing the tool holder to shift to the corresponding machining position. The slider is also equipped with a vertically adjustable rotary worktable. By adjusting the height of the tool holder on the rotary worktable in real time, the profile parameter p of the grinding wheel is adjusted when machining the toroidal worm gear. d In addition to adjusting the grinding wheel angle β, the rotation of the connecting cylinder is also used to adjust the grinding wheel angle β, which is used to process toroidal worm gears with different numbers of threads. This ensures that the machining process is automated, efficient, and accurate.

[0026] Third, the present invention features a tailstock and a spindle box that are positioned opposite each other and have an adjustable spacing in the clamping module design. The tailstock is connected to a pin, and a worm gear blank is clamped between the pin and the spindle box, thereby enabling stable clamping of worm gear blanks of different sizes to be processed. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the structure of the present invention;

[0028] Figure 2 This is a schematic diagram illustrating the principle of the surface tilt angle (i.e., grinding wheel tilt angle) in this invention.

[0029] Figure 3 This is a schematic diagram illustrating the principle of the axis deflection angle in this invention;

[0030] The markings in the diagram are as follows: 1. Machine tool body; 2. Horizontal guide rail; 3. Horizontal slide; 4. Arc guide rail; 5. Slider; 6. Lifting device; 7. Rotary table; 8. Longitudinal slide; 9. Spindle box; 10. Worm blank; 11. Grinding head; 12. Connecting cylinder; 13. Motor; 14. Ejector pin; 15. Tailstock; 16. Adjusting handle; 17. Axial guide rail; 18. Axial slide. Detailed Implementation

[0031] The present invention will now be described in detail with reference to the accompanying drawings and specific embodiments.

[0032] Example

[0033] like Figure 1 As shown, a guide rail machine tool for machining angle-trimmed toroidal worm gears includes a machine tool body 1. The machine tool body 1 is equipped with a horizontally movable tool setting module. The tool setting module is connected to a tool holder module that can undergo arc offset movement and vertical movement. The tool holder module is connected to a grinding wheel module that can move back and forth and flip. The machine tool body 1 is also equipped with a clamping module for clamping the worm gear blank 10. The grinding wheel module is located on the side of the worm gear blank 10. The tool holder module moves along a helical path to achieve angle trimming machining of the worm gear blank 10.

[0034] Specifically, the tool setting module includes a horizontal guide rail 2 located at the bottom of the machine tool body 1, a horizontal slide 3 mounted on the horizontal guide rail 2, a tool holder module slidably connected above the horizontal slide 3, and slide guide rails for connecting the tool holder module are provided on both sides of the top of the horizontal slide 3.

[0035] The tool holder module includes an arc guide rail 4, which moves along the slide guide rail. A slider 5 is installed on the arc guide rail 4. By changing the position of the slider 5, the tool holder is tilted to adjust the angle between the rotation axis of the tool holder and the worm axis. That is, the movement of the slider 5 is controlled by the axis deflection angle Δ∑, so that the tool holder is offset to the corresponding machining position.

[0036] The slider 5 is connected to a vertically movable rotary table 7, which is used to adjust the dressing parameters of the grinding wheel module when machining the toroidal worm. In this embodiment, a lifting device 6 is connected to the bottom of the rotary table 7. The height of the tool holder on the rotary table 7 is adjusted in real time by the lifting device 6 to realize the dressing parameter p when the grinding wheel is machining the toroidal worm. d With adjustments, the tool holder moves along a spiral path to achieve the angular shaping of the toroidal worm gear.

[0037] The grinding wheel module includes a longitudinal slide 8 connected to the top of the rotary table 7. The longitudinal slide 8 controls the forward and backward feed of the grinding wheel cutter holder. A connecting cylinder 12 connected to the grinding wheel is installed on the longitudinal slide 8. The grinding wheel tilt angle is adjusted by rotating the connecting cylinder 12 to process toroidal worm gears with different numbers of heads. The two ends of the connecting cylinder 12 are respectively connected to the grinding head 11 and the motor 13 for driving the grinding wheel.

[0038] The clamping module includes a tailstock 15 and a spindle box 9, which are positioned opposite each other and have an adjustable spacing. The tailstock 15 is connected to an ejector pin 14, which clamps a worm gear blank 10 between the ejector pin 14 and the spindle box 9. An axial slide 18 is connected to the tailstock 15 and is mounted on an axial guide rail 17, which is located on the top of the machine tool body 1. An adjusting handle 16 is connected to one end of the tailstock 15 for adjusting the spacing between the tailstock 15 and the spindle box 9, ensuring stable clamping of workpieces of different sizes.

[0039] The specific processing method of applying the above machine tool in practice includes the following steps:

[0040] S1. The worm blank is clamped in the corresponding position of the machine tool body using the clamping module and rotates.

[0041] S2. Control the tool setting module to move to the side position of the worm blank, and control the tool holder module to move closer to the worm blank.

[0042] S3. According to the set axis deflection angle Δ∑, control the slider in the tool holder module to move along the arc guide rail, causing the tool holder to tilt and shift to the corresponding processing position;

[0043] The connecting cylinder inside the control tool holder module rotates to adjust the grinding wheel tilt angle β, which is used to process toroidal worm gears with different numbers of threads;

[0044] Based on the worm gear blank rotation angle φ, the height Δd of the rotary table inside the tool holder module is controlled to adjust the dressing parameter p of the grinding wheel when machining the toroidal worm gear. d =Δd / φ, which causes the tool holder to move along the helical path to achieve the angular shaping of the toroidal worm.

[0045] This embodiment applies the above technical solution, taking the machining of a four-head toroidal worm gear angle shaping as an example. The machining center distance a = 160mm, and the machining transmission ratio i between the toroidal worm gear blank and the tool holder is... 1d=10. The specific implementation plan is as follows: A horizontal guide rail 2 is set on the machine tool body 1, and a movable horizontal slide 3 is installed on the horizontal guide rail 2 to realize the tool setting function; an arc guide rail 4 that can move along the guide rail on the horizontal slide 3 is also installed on the horizontal slide 3, and a slider 5 is installed on the arc guide rail 4. The movement of the slider 5 is controlled by the axis deflection angle Δ∑, so that the tool holder is offset to the corresponding machining position. A rotary worktable 7 that can be raised and lowered is also installed on the slider 5. The rotary worktable 7 allows the tool holder to rotate freely during the shaping process. The height Δd of the tool holder on the rotary worktable 7 is adjusted by the lifting device 6 to realize the shaping parameter p when the grinding wheel is machining the toroidal worm. d Adjustments.

[0046] To study the shaping parameter p during the processing d Specific details, such as Figure 2 As shown in the figure, O d φ is the axis of rotation of the tool holder. d The angle of the tool holder is r, and the profile of the grinding wheel head is r. b The worm gear's main base circle is tangent to the worm, and β represents the angle between the production surface and the tool holder's rotation axis at any machining position Q of the worm. During the rotation of the tool holder, a set of positions are selected as reference points, with tool holder rotation angles φ... d1 =0.288rad, φ d2 =0.345rad, φ d3 =0.431rad, φ d4 =0.502rad, φ d5 =0.665rad, at which point the corresponding worm gear blank rotation angle φ = φ d ×i 1d The φ1 = 2.88 rad, φ2 = 3.45 rad, φ3 = 4.31 rad, φ4 = 5.02 rad, and φ5 = 6.65 rad are respectively. The tool holder rise heights are Δd1 = 6.5758 mm, Δd2 = 4.9800 mm, Δd3 = 4.0845 mm, Δd4 = 4.1475 mm, and Δd5 = 5.7961 mm. The shaping parameter p d =Δd / φ, respectively: p d1 =2.283 mm / rad, p d2 =1.443 mm / rad, p d3 =0.948mm / rad, p d4 =0.826 mm / rad, p d5 = 0.872 mm / rad. Tool holder rotation angle φ at other positions. d and the corresponding shaping parameter p d The calculation can be performed using linear interpolation.

[0047] The rotation of the rotary table 7 allows the surface grinding head to reach different machining positions. A longitudinal slide 8 is also mounted on it to control the forward and backward feed of the grinding wheel holder. A connecting cylinder 12 for connecting the grinding wheel is mounted on the longitudinal slide 8. The grinding head 11 and the grinding wheel drive motor 13 are mounted on the connecting cylinder 12. The coordinate movement of each workpiece during the machining process is as follows: Figure 3 As shown in the figure, O od With O d O1 represents the static and dynamic coordinate systems of the tool holder, O2 represents the toroidal worm coordinate system, a is the machining center distance, Δd is the displacement along the tool holder axis, which is proportional to the worm blank rotation angle φ, and p is the shaping parameter. d =Δd / φ, and the angle between the tool holder axis and the grinding wheel axis is Δ∑+90°, where Δ∑ is the deflection angle of the tool holder axis. Tool holder and moving coordinate σ d (O d i d ,j d ,k d ( ) Fixed in phase, relative to the static coordinate σ od (O od i od ,j od ,k od The toroidal worm gear hob blank undergoes helical motion and is fixedly connected to the moving coordinate system σ1(O1; i1, j1, k1). Relative to the static coordinate system σ... o1 (O o1 i o1 ,j o1 ,k o1 It performs a rotary motion. The tool holder axis k... od The positive direction and the axis k of the toroidal worm blank o1 The positive included angle is 90° plus the axis deflection angle Δ∑. In this embodiment, the axis deflection angle Δ∑ = 2.359°, and the degree of deflection of the tool holder rotation axis is adjusted according to its size. The rotation of the connecting cylinder 12 can realize the adjustment of the grinding wheel tilt angle β. In this embodiment, the product surface tilt angle β = 22.5°.

[0048] In addition, the axial guide rail 17 installed on the machine tool body 1 is provided with an axial slide 18 that can move along the guide rail. The axial slide 18 is connected to the tailstock 15. The tailstock 15 is equipped with a center pin 14, which works together with the spindle box 9 installed on the other side of the machine tool body 1 to clamp the worm blank 10. The distance between the tailstock 15 and the spindle box 9 can be adjusted by operating the adjustment handle 16 to ensure stable clamping of workpieces of different sizes. In this embodiment, the working length Lw of the toroidal worm is 90mm.

[0049] In summary, when designing the special machine tool for machining angle-modified toroidal worm gears, this scheme considers two special functions of the tool holder: one is that the angle between the tool holder's rotation axis and the worm gear axis is 90° + Δ∑, meaning that the angle of the tool holder's axis must be adjustable according to Δ∑; the other is that once the inclination angle β of the production surface is determined, the height of the tool holder needs to be adjusted according to the modification parameter p. d Adjustments are made along the axis of the tool holder. Therefore, based on the principle of corner trimming, this solution, in the aforementioned toroidal worm gear guideway machine tool for corner trimming, controls the angle between the tool holder's rotation axis and the worm gear axis by changing the position of the slider on the arc guideway, causing the tool holder on the slider to tilt. The angle between the tool holder's rotation axis and the worm gear axis is set to 90° + Δ∑, and the specific position of the slider is adjusted according to the magnitude of Δ∑; simultaneously, the height Δd of the tool holder is adjusted by the lifting device to realize the trimming parameter p when the grinding wheel is machining the toroidal worm gear. d The adjustment of the tool holder along the spiral path realizes the angular shaping of the toroidal worm; the rotation of the connecting cylinder realizes the adjustment of the inclination angle β of the production surface, which is used to process toroidal worms with different numbers of heads.

[0050] In existing technologies for machining toroidal worm gears using flat grinding wheels, after machining one side of the worm gear tooth surface, the grinding wheel must be flipped or the worm gear rotated to machine the other side. This unilateral machining results in uneven stress distribution, affecting machining quality. The guideway-type machine tool proposed in this solution offers high stability and is suitable not only for machining toroidal worm gears with uniform stress distribution (double-cone envelope) but also for machining toroidal worm gears with uneven stress distribution (flat envelope). Compared to existing technologies, the guideway-type machine tool for machining angle-modified toroidal worm gears proposed in this solution possesses a unique shaping process and machining performance, effectively improving machining efficiency and the meshing quality of the worm pair. Furthermore, the machine tool has a simple structure and is easy to operate, solving the problems of existing toroidal worm gear machining machines being unable to perform angle modification and requiring multiple clamping operations, resulting in cumbersome procedures. It enables the completion of toroidal worm gear angle modification machining in a single clamping, improving the uneven stress distribution during unilateral grinding, and is suitable for machining toroidal worm gears with double-enveloping flat envelope, possessing high practical production value.

Claims

1. A guide rail type machine tool for machining angle-modified toroidal worm gears, characterized in that, The machine tool body (1) is provided with a horizontally movable tool setting module. The tool setting module is connected to a tool holder module that can perform arc offset movement and vertical movement. The tool holder module is connected to a grinding wheel module that can move back and forth and flip. The machine tool body (1) is also provided with a clamping module for clamping a worm blank (10). The grinding wheel module is located on the side of the worm blank (10). The tool holder module moves along a spiral path to realize the corner shaping of the worm blank (10). The tool holder module includes an arc guide rail (4), on which a slider (5) is installed. By changing the position of the slider (5), the tool holder is tilted to adjust the angle between the tool holder rotation axis and the worm axis. The slider (5) is connected to a rotary worktable (7) that can move up and down, which is used to adjust the shaping parameters of the grinding wheel module when machining the toroidal worm.

2. The guide rail type machine tool for machining angle-modified toroidal worm gears according to claim 1, characterized in that, The tool setting module includes a horizontal guide rail (2) located at the bottom of the machine tool body (1), and a horizontal slide (3) is installed on the horizontal guide rail (2). The tool holder module is slidably connected above the horizontal slide (3).

3. The guide rail type machine tool for machining angle-modified toroidal worm gears according to claim 2, characterized in that, The horizontal slide (3) has slide rails on both sides of its top for connecting the tool holder module.

4. The guide rail type machine tool for machining angle-modified toroidal worm gears according to claim 1, characterized in that, The bottom of the rotary table (7) is connected to a lifting device (6).

5. A guide rail type machine tool for machining angle-modified toroidal worm gears according to claim 1, characterized in that, The grinding wheel module includes a longitudinal slide (8) connected to the top of the rotary table (7). A connecting cylinder (12) connected to the grinding wheel is installed on the longitudinal slide (8). The grinding wheel tilt angle is adjusted by rotating the connecting cylinder (12). A grinding head (11) and a motor (13) for driving the grinding wheel are respectively connected to both ends of the connecting cylinder (12).

6. A guide rail type machine tool for machining angle-modified toroidal worm gears according to claim 1, characterized in that, The clamping module includes a tailstock (15) and a spindle box (9) that are arranged opposite to each other and have an adjustable spacing. The tailstock (15) is connected to a ejector pin (14), and a worm gear blank (10) is clamped between the ejector pin (14) and the spindle box (9).

7. A guideway machine tool for machining angle-modified toroidal worm gears according to claim 6, characterized in that, The tailstock (15) is connected to an axial slide (18), which is mounted on an axial guide rail (17) located on the top of the machine tool body (1).

8. A guide rail type machine tool for machining angle-modified toroidal worm gears according to claim 6, characterized in that, One end of the tailstock (15) is connected to an adjustment handle (16) for adjusting the distance between the tailstock (15) and the spindle box (9).

9. A machining method for a guideway machine tool using a machining angle-modified toroidal worm gear as described in claim 5, characterized in that, Includes the following steps: S1. The worm blank is clamped in the corresponding position of the machine tool body using the clamping module and rotates. S2. Control the tool setting module to move to the side position of the worm blank, and control the tool holder module to move closer to the worm blank. S3. Based on the set axis deflection angle Δ∑ The slider inside the control tool holder module moves along the arc guide rail, causing the tool holder to tilt and shift to the corresponding machining position; The connecting cylinder inside the control tool holder module rotates to adjust the grinding wheel tilt angle. β Used to process toroidal worm gears with different numbers of threads; Based on the rotation angle of the worm gear blank φ Control the height of the rotary table inside the tool holder module Δd To adjust the dressing parameters of the grinding wheel when machining the toroidal worm. p d =Δ d / φ This allows the tool holder to move along a spiral path to achieve the corner shaping of the toroidal worm.

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