Two-axis double feed numerical control thread rolling machine

Abstract

The application relates to the technical field of metal processing equipment, in particular to a two-shaft bidirectional feeding numerical control thread rolling machine, which comprises left and right roller assemblies symmetrically arranged on the two sides of a machine table, two groups of roller assemblies are connected with a planetary roller screw through a sliding block assembly, the planetary roller screw is driven by a servo motor, a pull rod extending in the axial direction is arranged between the two roller assemblies, the pull rod is fixedly connected with the corresponding roller assembly through a pull rod nut at both ends, a workpiece positioning area is arranged in the middle of the machine table, and a feeding assembly is arranged above the machine table; the planetary roller screw is adopted as a core transmission component, the linear contact rolling friction setting is compared with that of a traditional ball screw, the bearing capacity is increased by about 50%, the volume is smaller, and the precision deficiency problem in a high-load processing scene is effectively solved.

Description

Technical Field

[0001] This application relates to the field of metal processing equipment technology, and in particular to a two-axis bidirectional feed CNC thread rolling machine. Background Technology

[0002] In the field of machining, screw (roller, ball screw) processing equipment is widely used in automotive parts, aerospace, precision instruments, and other fields. Traditional screw thread rolling machines typically use a single-sided feed method, where the screw is pressed against a fixed-sided roller by the moving roller on one side. The left and right rollers then clamp the workpiece for thread rolling. When machining screws with high precision requirements or long screws, this single-sided feed can easily cause the long screw to oscillate, affecting machining accuracy. Furthermore, the main power system of traditional thread rolling machines usually consists of a single motor combined with a reduction gearbox, transmitting power to the rollers via a cross-shaped drive shaft. This method is suitable for low-precision screw production; when producing high-precision screws, the cross-shaped drive shaft often becomes too volatile due to joint rotation. Wear causes the two hobbing dies to rotate out of sync, further affecting the accuracy of the lead screw. In addition, in order to meet the needs of producing screws of different specifications, a mechanical clutch dial needs to be installed between the power gearbox and the cross drive shaft. The dial is disassembled and adjusted manually. Manual operation is not only inefficient, but the structure also affects the power transmission. If the mechanical clutch dial has too many graduations in the 360-degree circumference, the clutch power output will be affected because the grooves of the graduations are too fine and the frictional engagement force of the clutch disc contact surface is insufficient. If the graduations are too few, the machining accuracy of the workpiece will be affected.

[0003] The cooling systems of existing equipment are generally quite simple, resulting in low efficiency in the collection and recycling of cutting fluid, which easily leads to resource waste and environmental pollution. At the same time, the coordinating positioning accuracy of the clamping mechanism and roller assembly of the feeding component is insufficient, resulting in poor workpiece stability during the machining process. Especially under high speed or high load conditions, it is easy to cause workpiece slippage or overturning, affecting the machining quality. Utility Model Content

[0004] In view of the above, it is necessary to provide a two-axis bidirectional feed CNC thread rolling machine.

[0005] This application provides a two-axis bidirectional feed CNC thread rolling machine, including left and right roller assemblies symmetrically arranged on both sides of the machine base and an electrical control cabinet located on one side of the machine base. The two sets of roller assemblies are respectively connected to planetary roller screws through slider assemblies. The planetary roller screws are driven by a first servo motor. An axially extending tie rod is provided between the two roller assemblies. The two ends of the tie rod are fixedly installed on two supports by tie rod nuts. A workpiece positioning area is provided in the middle of the machine base, and a feeding assembly is provided above it.

[0006] In one possible implementation, the lead screw seat of the planetary roller screw is fixedly mounted on the slider, the support is located on one side of the slider, and the support is connected to the first servo motor through a reducer to form a symmetrically arranged left and right support assembly. The slider assembly includes a slider and a guide rail that cooperate with the planetary roller screw.

[0007] In one possible implementation, the roller assembly includes a support mounting plate fixed to the slider by a mounting plate, the support mounting plate being provided with an adjustable support, the support being bolted to a roller, and the roller axis being arranged perpendicular to the planetary roller screw axis. The slider and mounting plate are equipped with grating positioning components on both sides to ensure that the toothed wheel is parallel to the workpiece.

[0008] In one possible implementation, the second servo motor is connected to the ball cage drive shaft via a gearbox, and the ball cage drive shaft is provided with constant velocity universal joints at both ends; The gearbox input shaft is connected to the second servo motor via a reducer, and the two output shafts are respectively connected to the drive shafts of the left and right rollers.

[0009] In one possible implementation, the feeding assembly includes a clamping mechanism for coaxially arranging the workpiece and a linear feed mechanism. The central axis of the clamping mechanism coincides with the symmetrical center plane of the two rollers, and a grating positioning assembly is provided on one side of the clamping mechanism.

[0010] In one possible implementation, the lower part of the machine base integrates a cooling system, including a cutting fluid output pipe connected to a cutting fluid pump and a cutting fluid collection device, the upper part of which is provided with a tray with a filter screen, and the cutting fluid collection port is located directly below the roller assembly.

[0011] In one possible implementation, the tie rod is made of prestressed alloy steel, with reverse threaded sections at both ends, forming a helical pair with the tie rod nuts of the left and right roller assemblies respectively, and a light is provided in the middle of the tie rod.

[0012] In one possible implementation, the guide rails of the slider assembly are arranged parallel to both sides of the planetary roller screw, the surface of the guide rails is provided with a wear-resistant coating, and the contact surface between the slider and the guide rails is provided with a self-lubricating pad.

[0013] In one possible implementation, the electrical control cabinet is equipped with a motion control module, and the feed parameters of the first and second servo motors can be set independently through the control panel.

[0014] In one possible implementation, the cutting fluid collection device forms a 3-5° inclination angle with the bottom surface of the machine base, and a drain outlet is provided at its lowest point. The filter screen adopts a multi-layer stainless steel woven mesh structure.

[0015] 1. In the above-mentioned two-axis bidirectional feed CNC thread rolling machine, the planetary roller screw driven by the first servo motor is used as the core transmission component to independently drive the left and right roller assemblies for feeding. The bidirectional synchronous feeding is based on the center line of the screw to be processed. Even when processing long screws, there will be no swaying, which improves the processing accuracy. Compared with the traditional ball screw, its line contact rolling friction setting increases the load-bearing capacity by about 50% and has a smaller size, effectively solving the problem of insufficient accuracy in high-load processing scenarios.

[0016] 2. This utility model independently drives the left and right roller assemblies through a second servo motor, and achieves independent power output through a gearbox and ball cage drive shaft. While ensuring high-power output of independent power on both axes, it also ensures stability. In addition, since the power output method of servo single-axis transmission gearbox and ball cage drive shaft is adopted, the angle of the two axes can be directly adjusted through the CNC system when processing different parts, without the need for angle adjustment by mechanical dial. This not only improves the processing accuracy, but also makes the power transmission more reliable.

[0017] 3. This utility model features an adjustable support structure for the roller assembly, allowing dynamic adjustment of the roller position according to the workpiece diameter to adapt to different processing requirements. The tie rod is made of prestressed alloy steel, with reverse threaded sections at both ends forming a helical pair with the tie rod nut, enhancing structural strength and resisting vibration and impact. The wear-resistant coating on the guide rail surface and the self-lubricating pad on the slider significantly reduce friction loss and extend the equipment's service life. Furthermore, the cooling system integrates multi-layer stainless steel filters and an inclined drainage structure, improving the filtration efficiency and recycling rate of cutting fluid, reducing resource waste and environmental pollution.

[0018] 4. This utility model achieves closed-loop control through an electronic control system, a motion control module, and a grating positioning component. Combined with encoder feedback signals, it ensures high precision and stability in the processing process. At the same time, it supports independent parameter setting, improving the ease of operation. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of this utility model, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] Figure 1 This is a partial structural diagram of one embodiment of this application; Figure 2 This is one embodiment of the present application Figure 1 Mid-section structural schematic diagram; Figure 3 This is a schematic diagram of the overall structure in one embodiment of this application; Figure 4 This is a schematic diagram of the cutting fluid collection device in one embodiment of this application; Figure 5 This is a partial cross-sectional structural diagram of one embodiment of this application; Figure 6 This is one embodiment of the present application Figure 5 Exploded view of the middle structure; Figure 7 This is an enlarged view of a partial structure in one embodiment of this application.

[0021] Explanation of key component symbols: 101. First servo motor; 102. Second servo motor; 2. Planetary roller screw; 3. Feeding assembly; 4. Grating positioning assembly; 5. Roller; 6. Gearbox; 7. Ball cage drive shaft; 8. Bolt; 9. Tie rod nut; 10. Support; 11. Electrical control cabinet; 12. Operation control panel; 13. Tie rod; 14. Support mounting plate; 15. Mounting plate; 16. Cutting fluid collection device; 17. Filter screen; 18. Tray; 19. Cutting fluid output pipe; 20. Cutting fluid pump; 21. Machine base; 22. Support assembly; 23. Roller assembly; 24. Slider assembly; 25. Reducer; 26. Support; 27. Screw seat; 28. Slider; 29. ​​Workpiece; 30. Lamp. Detailed Implementation

[0022] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are some embodiments of this application, but not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0023] Please see Figures 1-7 This embodiment provides a technical solution: a two-axis bidirectional feed CNC thread rolling machine, including left and right roller assemblies 23 symmetrically arranged on both sides of the machine base 21 and an electrical control cabinet 11 located on one side of the machine base 21. The two sets of roller assemblies 23 are respectively connected to planetary roller screws 2 through slider assemblies 24. The planetary roller screws 2 are driven by a first servo motor 101. The first servo motor is set on each of the left and right sides of the machine base, and each independently drives the planetary roller screw. An axially extending tie rod 13 is provided between the two roller assemblies 23. The two ends of the tie rod 13 are fixedly connected to the corresponding support 26 through tie rod nuts 9. A workpiece positioning area is provided in the middle of the machine base 21, and a feeding assembly 3 is provided above it.

[0024] In some embodiments, the lead screw seat 27 of the planetary roller screw 2 is fixedly mounted on the slider 28, the support 26 is located on one side of the slider 28, and the support 26 is connected to the first servo motor 101 through the reducer 25 to form symmetrically arranged left and right support assemblies 22. The slider assembly 24 includes the slider 28 that cooperates with the planetary roller screw 2 and the guide rail. The cutting fluid collection device 16 forms a 3-5° inclination angle with the bottom surface of the machine base 21, and its lowest point is provided with a drain port. The filter screen 17 adopts a multi-layer stainless steel woven mesh structure.

[0025] It should be noted that this two-axis bidirectional feed CNC thread rolling machine includes core components such as a machine base 21, a planetary roller screw 2, a first servo motor 101, a roller assembly 23, a slider assembly 24, a tie rod 13, and a feeding assembly 3. The specific structure and working principle of each component will be explained in detail below.

[0026] The machine base 21, serving as the foundation support structure of the entire equipment, is constructed from high-strength cast iron or steel, possessing excellent rigidity and vibration resistance. Left and right roller assemblies 23 are symmetrically arranged on both sides of the machine base, and the two sets of roller assemblies are connected to the planetary roller screw 2 via a slider assembly 24. The planetary roller screw 2 is driven by the first servo motor 101, enabling bidirectional feed. A workpiece positioning area is located in the middle of the machine base to fix the workpiece 29 to be processed.

[0027] The planetary roller screw 2 is the transmission component of this invention. Its structure includes a screw body, a planetary roller cage, a nut, and a support 26. The screw body is connected to the servo motor 1 via a reducer 25, forming symmetrically arranged left and right support assemblies 22. The working principle of the planetary roller screw is based on the line contact rolling friction between the rollers and the screw and nut. Compared with traditional ball screws, it has higher load-bearing capacity, smaller size, and lower noise.

[0028] In some embodiments, the roller assembly 23 includes a support mounting plate 14 fixed to the slider 28 by a mounting plate 15, an adjustable support 10 is provided on the support mounting plate 14, and a roller 5 is mounted on the support 10 by bolts 8, the axis of the roller 5 being arranged perpendicular to the axis of the planetary roller screw 2. The slider 28 and the mounting plate 15 are equipped with grating positioning components 4 on both sides to ensure that the gear hobbing wheel is parallel to the workpiece. The grating positioning components 4 are used to monitor the position of the workpiece in real time and feed it back to the control system to improve machining accuracy.

[0029] Furthermore, the roller assembly 23 includes a support mounting plate 14 fixed to the slider 28 via a mounting plate 15, and an adjustable support 10 is provided on the support mounting plate 14. A roller 5 is mounted on the support 10 via bolts 8, and the axis of the roller 5 is arranged perpendicular to the axis of the planetary roller screw 2. The adjustable support 10 of the roller assembly 23 allows the roller position to be adjusted according to the workpiece diameter, thereby adapting to different processing requirements.

[0030] In some embodiments, the second servo motor 102 is connected to the ball cage drive shaft 7 via a gearbox 6, and the ball cage drive shaft 7 is provided with constant velocity universal joints at both ends; The input shaft of the gearbox 6 is connected to the second servo motor 102 via a reducer 25, and the two output shafts are respectively connected to the drive shafts of the left and right rollers 5. The second servo motor 102 is connected to the ball cage drive shaft 7 via the gearbox 6. The gearbox 6 is equipped with a transfer mechanism, whose input shaft is connected to the second servo motor 102 via a reducer 25, and the two output shafts are respectively connected to the drive shafts of the left and right rollers 5. The ball cage drive shaft 7 is equipped with constant velocity universal joints at both ends to ensure smooth and efficient power transmission. The constant velocity universal joint adopts a ball cage structure with V-shaped inner and outer raceways, allowing axial movement to compensate for length changes during front wheel bounce. The maximum allowable angle is 22°, and the axial displacement can reach 45mm.

[0031] Furthermore, the feeding assembly 3 includes a clamping mechanism for the workpiece 29 coaxially arranged and a linear feed mechanism. The central axis of the clamping mechanism coincides with the symmetrical center plane of the two rollers 5. The feeding assembly 3 includes a clamping mechanism for the workpiece 29 coaxially arranged and a linear feed mechanism. The central axis of the clamping mechanism coincides with the symmetrical center plane of the two rollers 5 to ensure that the workpiece remains stable during processing.

[0032] In some embodiments, the lower part of the machine base 21 integrates a cooling system, including a cutting fluid output pipe 19 connected to a cutting fluid pump 20 and a cutting fluid collection device 16. The cutting fluid collection device 16 has a tray 18 with a filter screen 17 on its upper part, and the cutting fluid collection port is located directly below the roller assembly 23. The filter screen 17 has a multi-layer stainless steel woven mesh structure, which can effectively filter metal debris from the cutting fluid, extend equipment life, and reduce environmental pollution. The cutting fluid collection device 16 forms a 3-5° inclination angle with the bottom surface of the machine base 21, and its lowest point has a drain port, facilitating the recovery and recycling of the cutting fluid.

[0033] In some embodiments, the pull rod 13 is made of prestressed alloy steel, with reverse threaded sections at both ends, forming helical pairs with the pull rod nuts 9 of the left and right roller assemblies 23, respectively. A light 30 is provided in the middle of the pull rod 13. An axially extending pull rod 13 is provided between the two sets of roller assemblies 23, with both ends of the pull rod 13 fixedly connected to the corresponding roller assembly 23 via pull rod nuts 9. The pull rod 13 is made of prestressed alloy steel, with reverse threaded sections at both ends, forming helical pairs with the pull rod nuts 9 of the left and right roller assemblies 23, respectively. A light 30 is provided in the middle of the pull rod for assisting workpiece positioning and visual monitoring during the processing.

[0034] In some embodiments, the guide rails of the slider assembly 24 are arranged parallel to both sides of the planetary roller screw 2, and the surface of the guide rails is provided with a wear-resistant coating. The contact surface between the slider 28 and the guide rails is provided with a self-lubricating pad. The slider assembly 24 includes a slider 28 that cooperates with the planetary roller screw 2 and a guide rail. The guide rails are arranged parallel to both sides of the planetary roller screw 2 and have a wear-resistant coating on their surface. The contact surface between the slider 28 and the guide rails is provided with a self-lubricating pad to reduce friction loss and extend service life.

[0035] The electrical control cabinet 11 houses a motion control module, allowing independent setting of the feed parameters for the first and second servo motors via the control panel 12. The motion control module employs a high-performance PLC or embedded control system, supporting multi-axis linkage and precision positioning. The control system acquires real-time displacement data of the planetary roller screw 2 via an encoder, and combines this with feedback signals from the grating positioning component 4 to achieve closed-loop control, ensuring high precision and stability during the machining process.

[0036] In summary, this invention achieves high-precision and high-efficiency bidirectional feed thread rolling through innovative structural designs including planetary roller screws, servo motors, and constant velocity universal joints. The coordinated operation of all components ensures the stability, durability, and intelligence of the equipment, meeting the stringent requirements of modern industry for precision machining.

[0037] The planetary roller screw 2 and the ball cage drive shaft 7 are implemented using the structural and technical features currently employed in technology.

[0038] In practical applications, the two-axis bidirectional feed CNC thread rolling machine of this invention drives the planetary roller screw 2 through the first servo motor 101 to realize the bidirectional feed motion of the roller assembly 23. The specific operation process is as follows: ① Place the workpiece 29 to be processed in the clamping mechanism of the feeding assembly 3, and adjust the position of the workpiece by the grating positioning assembly 4 so that it coincides with the symmetrical center plane of the two rollers 5.

[0039] ② Set the feed parameters of the first servo motor 101, including speed, acceleration, and stroke range, through the control panel 12. Start the first servo motor 101, and the planetary roller screw 2 starts to rotate, driving the slider assembly 24 to move along the guide rail, thereby driving the roller assembly 23 to move closer to the workpiece 29.

[0040] ③After the roller 5 comes into contact with the workpiece 29, the second servo motor 102 is connected to the ball cage drive shaft 7 through the gearbox 6, and the two shafts drive the left and right rollers to rotate.

[0041] ④ Under the interaction of the bidirectional feed and the rotation of the two axes, the workpiece is subjected to thread rolling.

[0042] The tie rod 13 maintains the synchronous movement of the left and right roller assemblies 23 via the tie rod nut 9, ensuring the stability of the machining process. The cooling system sprays cutting fluid into the machining area through the cutting fluid pump 20 to reduce the temperature of the workpiece and rollers, extending tool life.

[0043] ⑤ After machining is completed, the servo motor 101 drives the planetary roller screw 2 to retract to the initial position. The cutting fluid collection device 16 guides the cutting fluid into the drain port through the tilt angle, realizing the recovery and recycling of waste fluid.

[0044] In this document, the directional terms such as front, back, top, and bottom are defined based on the location of the components in the accompanying drawings and their relative positions to each other, solely for the purpose of clarity and convenience in expressing the technical solution. It should be understood that the use of these directional terms should not limit the scope of protection claimed in this application.

[0045] Obviously, the above-described embodiments are only some embodiments of this application, and not all embodiments. This application is not limited to the details of the above embodiments. Any appropriate changes or modifications made by those skilled in the art are considered to be within the scope of the patent of this application.

Claims

1. A two-axis, two-way feed CNC thread rolling machine, characterized in that, The machine includes left and right roller assemblies (23) symmetrically arranged on both sides of the machine base (21) and an electrical control cabinet (11) located on one side of the machine base (21). The two sets of roller assemblies (23) are connected to the planetary roller screw (2) through the slider assembly (24). The planetary roller screw (2) is driven by the first servo motor (101). An axially extending tie rod (13) is provided between the two roller assemblies (23). The two ends of the tie rod (13) are fixedly installed on two supports (26) through tie rod nuts (9). A workpiece positioning area is provided in the middle of the machine base (21), and a feeding assembly (3) is provided above it.

2. The two-axis bidirectional feed CNC thread rolling machine according to claim 1, characterized in that, The lead screw seat (27) of the planetary roller screw (2) is fixedly installed on the slider (28). The support (26) is located on one side of the slider (28). The support (26) is connected to the first servo motor (101) through the reducer (25) to form a symmetrically arranged left and right support assembly (22). The slider assembly (24) includes a slider (28) that cooperates with the planetary roller screw (2) and a guide rail.

3. The two-axis bidirectional feed CNC thread rolling machine according to claim 2, characterized in that, The roller assembly (23) includes a support mounting plate (14) fixed to the slider (28) by a mounting plate (15), an adjustable support (10) is provided on the support mounting plate (14), and a roller (5) is mounted on the support (10) by bolts (8), the axis of the roller (5) being arranged perpendicular to the axis of the planetary roller screw (2). The slider (28) and the mounting plate (15) are provided with grating positioning components (4) on both sides to ensure that the toothed wheel is parallel to the workpiece.

4. The two-axis bidirectional feed CNC thread rolling machine according to claim 1, characterized in that, The second servo motor (102) is connected to the ball cage drive shaft (7) through the gearbox (6), and the ball cage drive shaft (7) is provided with constant velocity universal joints at both ends; The input shaft of the gearbox (6) is connected to the second servo motor (102) via a reducer (25), and the two output shafts are respectively connected to the drive shafts of the left and right rollers (5).

5. The two-axis bidirectional feed CNC thread rolling machine according to claim 1, characterized in that, The feeding assembly (3) includes a clamping mechanism for coaxially arranging the workpiece (29) and a linear feeding mechanism, wherein the central axis of the clamping mechanism coincides with the symmetrical central plane of the two rollers (5).

6. The two-axis bidirectional feed CNC thread rolling machine according to claim 1, characterized in that, The lower part of the machine base (21) is integrated with a cooling system, including a cutting fluid output pipe (19) connected by a cutting fluid pump (20) and a cutting fluid collection device (16). The upper part of the cutting fluid collection device (16) is provided with a tray (18) with a filter screen (17), and the cutting fluid collection port is located directly below the roller assembly (23).

7. The two-axis bidirectional feed CNC thread rolling machine according to claim 1, characterized in that, The pull rod (13) is made of prestressed alloy steel and has reverse thread sections at both ends, which form a helical pair with the pull rod nuts (9) of the left and right roller assemblies (23) respectively. A lamp (30) is provided in the middle of the pull rod (13).

8. The two-axis bidirectional feed CNC thread rolling machine according to claim 2, characterized in that, The guide rail of the slider assembly (24) is arranged parallel to both sides of the planetary roller screw (2), and the surface of the guide rail is provided with a wear-resistant coating. The contact surface between the slider (28) and the guide rail is provided with a self-lubricating pad.

9. The two-axis bidirectional feed CNC thread rolling machine according to claim 1, characterized in that, The electrical control cabinet (11) is equipped with a motion control module, and the feed parameters of the first and second servo motors can be set independently through the operation control panel (12).

10. The two-axis bidirectional feed CNC thread rolling machine according to claim 6, characterized in that, The cutting fluid collection device (16) forms a 3-5° inclination angle with the bottom surface of the machine base (21), and a drain port is provided at its lowest point. The filter screen (17) adopts a multi-layer stainless steel woven mesh structure.

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