Seven-axis five-link vertical CNC spiral bevel gear grinding machine

Abstract

The application discloses a seven-axis five-linkage vertical numerical control spiral bevel gear grinding machine tool, which comprises a bed body, a stand column arranged on the bed body, an X-axis guide rail and an X-axis linear motor arranged on the top of the stand column, a middle drag plate arranged on the X-axis guide rail and connected with the X-axis linear motor, a Y-axis guide rail and a Y-axis linear motor arranged on the top of the middle drag plate, a Y-axis ram arranged on the Y-axis guide rail and connected with the Y-axis linear motor, a Z-axis guide rail and a Z-axis linear motor arranged on the front end surface of the Y-axis ram, a Z-axis ram arranged on the Z-axis guide rail and connected with the Z-axis linear motor, a grinding wheel motorized spindle arranged in the Z-axis ram and parallel to the Z-axis guide rail, a B-axis numerical control rotary table arranged in the middle of the stand column, and an A-axis workpiece box arranged on the B-axis numerical control rotary table. The three linear axes of the application are driven by linear motors, and no mechanical transmission error and reverse clearance exist, so that the response speed is high, the positioning precision is high, the smallest modulus of the spiral bevel gear that can be machined is 0.8 mm, and the demand of the market for machining small modulus spiral bevel gears can be met.

Description

Technical Field

[0001] This invention relates to the field of CNC machining, and in particular to a seven-axis, five-linkage vertical CNC spiral bevel gear grinding machine. Background Technology

[0002] Existing spiral bevel gear grinding machines are all horizontal structures. The machine bed has a chip removal groove located below the machining area, precisely at the intersection of the horizontal X and Z axes. During grinding, the grinding oil cools and flushes the grinding wheel and workpiece surfaces, carrying impurities and chips from the grinding wheel surface into the chip removal groove. As machining time increases, changes in the grinding oil temperature can cause thermal deformation of the machine bed, affecting machining accuracy. The three linear axes of the horizontal machine tool are driven by servo motors and lead screw assemblies for horizontal and vertical feed. Prolonged operation of the lead screw causes wear between the lead screw grooves and the steel balls, leading to increasing operating errors. Over time, this directly affects the quality of the spiral bevel gear teeth, necessitating lead screw replacement to meet machining requirements. As the core component of the entire machine tool, the B-axis CNC rotary table has a particularly complex structure. It combines a gear-driven rapid traverse mechanism and a lead screw-driven precision feed mechanism to achieve precise angular displacement control of the B-axis CNC rotary table within the range of -5° to 90°. The rapid traverse mechanism and the precision feed mechanism use hydraulic oil pressure to control the clamping and loosening of the B-axis piston to achieve motion switching. When the rapid traverse mechanism is working, a 0.5mm gap is maintained between the B-axis piston ring and the fine adjustment ring, and the precision feed mechanism is not working at this time. When the precision feed mechanism is working, the B-axis piston ring must press against the fine adjustment ring. At this time, the precision feed mechanism drives the gear-driven rapid traverse mechanism to rotate around the B-axis together. There are certain difficulties in the motion switching between the two mechanisms. The actual gap value of the B-axis piston ring and the fine adjustment ring cannot be monitored. If the rapid traverse mechanism is started before the ring is completely disengaged, an impact force will be generated, which may damage the teeth of the driving and driven gears. The only solution is to delay the motion switching time of the two mechanisms through program control, which affects the machining efficiency. With the continuous innovation of spiral bevel gear processing technology, higher requirements have been placed on the rigidity, processing accuracy, processing efficiency, core technology breakthroughs, and innovation leadership of spiral bevel gear processing machine tools. The structure and components of CNC spiral bevel gear processing machine tools need to be improved and upgraded. Therefore, it is necessary to invent a vertical CNC spiral bevel gear grinding machine tool. Summary of the Invention

[0003] The purpose of this invention is to provide a seven-axis, five-linkage vertical CNC spiral bevel gear grinding machine tool driven by a linear motor, thereby solving the above-mentioned problems.

[0004] To solve the above-mentioned technical problems, the technical solution provided by the present invention is as follows:

[0005] A seven-axis, five-linkage vertical CNC spiral bevel gear grinding machine tool is disclosed. The machine tool adopts a C-type structure and includes a bed. A column is located at the top rear of the bed. Two X-axis guideways are mounted on the top of the column. A middle slide is slidably mounted on the X-axis guideways. Two horizontal Y-axis guideways, perpendicular to the X-axis guideways, are slidably mounted on the top of the middle slide. A Y-axis ram is mounted on the two Y-axis guideways. Two vertical Z-axis guideways are slidably mounted on the front end face of the Y-axis ram. A Z-axis ram is mounted on the two Z-axis guideways. A grinding wheel electric spindle, parallel to the Z-axis guideways, is installed inside the Z-axis ram. A grinding wheel is mounted at the lower end of the grinding wheel electric spindle. A B-axis CNC rotary table, with its rotation axis parallel to the Y-axis guideways, is mounted in the middle of the column. An A-axis workpiece box, capable of driving the workpiece to rotate, is mounted on the B-axis CNC rotary table. The rotation axis of the A-axis workpiece box is parallel to the rotation axis of the B-axis CNC rotary table. The axes of rotation are coplanar and perpendicular to each other; the top of the column is also equipped with an X-axis linear motor located between the two X-axis guide rails, and the bottom of the middle slide plate is connected to the X-axis linear motor; the top of the middle slide plate is also equipped with a Y-axis linear motor located between the two Y-axis guide rails, and the bottom of the Y-axis slide is connected to the Y-axis linear motor; the front end face of the Y-axis slide plate is also equipped with a Z-axis linear motor located between the two Z-axis guide rails, and the rear side of the Z-axis slide plate is connected to the Z-axis linear motor; the X-axis linear motor directly drives the middle slide plate, Y-axis slide plate, Z-axis slide plate and grinding wheel electric spindle to move left and right along the X-axis direction, the Y-axis linear motor directly drives the Y-axis slide plate, Z-axis slide plate and grinding wheel electric spindle to move back and forth along the Y-axis direction, and the Z-axis linear motor directly drives the Z-axis slide plate and grinding wheel electric spindle to move up and down along the Z-axis direction.

[0006] As a further improvement to the above technical solution:

[0007] Preferably, there is a gap of 0.8 to 1 mm between the coil and the magnetic unit of the linear motor, and the magnetic unit is composed of multiple pieces assembled according to the stroke length.

[0008] Preferably, the coil of the X-axis linear motor is mounted on the bottom center of the middle slide plate via a first coil mounting plate, and the magnetic unit of the X-axis linear motor is mounted on the top center of the column; the coil of the Y-axis linear motor is mounted on the top center of the middle slide plate via a second coil mounting plate, and the magnetic unit of the Y-axis linear motor is mounted on the bottom center of the Y-axis slide; the coil of the Z-axis linear motor is mounted on the front end face center of the Y-axis slide via a third coil mounting plate, and the magnetic unit of the Z-axis linear motor is mounted on the rear center of the Z-axis slide.

[0009] Preferably, the B-axis CNC rotary table includes a B-axis bridge mounted on the outside of the column, and a first torque motor, rotary table bearing, angle encoder, inner circumferential clamp, and bushing mounted inside the column. The bushing includes a large-diameter end and a small-diameter end that are independent of each other. The large-diameter end and the small-diameter end are connected together by an embedded connecting bushing. The small-diameter end of the bushing is supported on the column by the rotary table bearing and extends outward from the front end face of the column. The large-diameter end of the bushing is connected to the rotor of the first torque motor. The bridge is U-shaped, with one end pivotally connected to an auxiliary support mounted on the front side of the bed, and the other end pivotally connected to the front end of the column and connected to the small-diameter end of the bushing. The first torque motor directly drives the B-axis bridge and the A-axis workpiece box to rotate. The angle encoder is located on the adapter spindle at the rear end of the first torque motor to detect the angular displacement of the B-axis CNC rotary table. The inner circumferential clamp is located on the outer circumference of the connecting bushing to control the braking of the B-axis CNC rotary table at any angle position within ±120°.

[0010] Preferably, a vertically arranged balancing oil cylinder is provided at the top center of the Z-axis slide, and a temperature sensor is provided on the outer side of the Z-axis slide to monitor the temperature rise of the grinding wheel electric spindle in real time.

[0011] Preferably, two sets of guide rail brakes are fixedly provided on the front end surface of the Y-axis slide to hold the two Z-axis guide rails and prevent the Z-axis slide and the grinding wheel electric spindle from falling. There is a gap between the guide rail brakes and the working surfaces of the Z-axis guide rails that move up and down.

[0012] Preferably, an online measurement system is provided on the right side of the Z-axis slide. The measurement direction of the online measurement system is parallel to the rotation axis of the grinding wheel electric spindle. The online measurement system includes a vertically arranged piston rod, and a probe body and a ruby ​​ball probe are installed at the lower end of the piston rod.

[0013] Preferably, a grinding wheel dresser is provided on the left side of the front end face of the column. The rotation axis of the grinding wheel dresser is parallel to the rotation axis of the grinding wheel electric spindle. The grinding wheel dresser is directly driven by a high-speed electric spindle, and a diamond roller is installed at the top of the high-speed electric spindle.

[0014] Preferably, the front side of the bed is provided with a funnel-shaped chip removal groove, and a movable oil receiving tank is provided directly below the funnel-shaped chip removal groove. The oil receiving tank is connected to a cooling temperature control filter device.

[0015] As a further improvement to the above solution, the seven-axis five-linkage vertical CNC spiral bevel gear grinding machine tool of the present invention can also expand the gear milling processing function. When expanding, it is only necessary to replace the grinding wheel electric spindle with the gear milling electric spindle. The structure of the two types of machines, the gear milling machine and the gear grinding machine, is universal. The gear milling machine does not need to install grinding wheels and grinding wheel dressers.

[0016] Compared with the prior art, the advantages of the present invention are as follows:

[0017] 1) The machine tool layout of the present invention is reasonable, the structure is compact, it is easy to operate, and the machining accuracy is stable;

[0018] 2) The three linear axes of the X-axis, Y-axis and Z-axis in this invention are all driven by domestic linear motors. The structure is simpler than that of traditional servo motor driven lead screw assembly transmission. It does not require lead screw, lead screw bearing, bearing seat and other parts. There is no mechanical contact. There is a gap of 0.8 to 1 mm between the coil and the magnetic unit. There is no mechanical transmission error and backlash. The response speed is fast and the positioning accuracy is high. The positioning accuracy of the linear axis is no longer affected by the stroke. The positioning accuracy reaches 0.002 mm. It can also achieve micro-feed as low as 0.1 micrometer.

[0019] 3) This invention can process spiral bevel gears with a minimum module of 0.8mm, making it particularly suitable for precision instruments, aerospace, robotics, automobiles, electronic equipment and other fields, and can well meet the needs of the small module spiral bevel gear processing market;

[0020] 4) This invention uses the domestically produced i5 CNC system, eliminating the need to rely on foreign CNC systems and solving the bottleneck problem of core technologies;

[0021] 5) The B-axis CNC rotary table and A-axis workpiece box in this invention are driven to rotate by a torque motor built into the column, forming a cradle-like structure, which can solve the problems of low processing efficiency caused by multiple B-axis drive links and high failure rate in the prior art.

[0022] 6) The grinding wheel electric spindle in this invention is equipped with an automatic temperature compensation system, namely a temperature sensor set on the outer side of the Z-axis slide, which can monitor the temperature rise of the grinding wheel electric spindle in real time and automatically compensate for the thermal deformation of the grinding wheel electric spindle according to the machine tool thermal deformation model established by the i5 CNC system, which can further improve the machining stability of the machine tool.

[0023] 7) The gear grinding machine of the present invention can be used in the same way as the gear milling machine. When the gear grinding machine is converted into a gear milling machine, it is only necessary to replace the grinding wheel electric spindle with the gear milling electric spindle. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the structure of the present invention.

[0025] Figure 2 This is a schematic diagram of the main structure of the present invention.

[0026] Figure 3 yes Figure 2 N1-N1 sectional view (partial sectional view).

[0027] Figure 4 yes Figure 2N2-N2 sectional view.

[0028] Figure 5 This is a partial sectional view of the installation of the Y-axis linear motor in this invention.

[0029] Legend:

[0030] 1. Bed; 2. A-axis workpiece box; 3. B-axis CNC rotary table; 4. Grinding wheel dresser; 5. Grinding wheel electric spindle; 6. Online measurement system; 7. Z-axis ram; 8. Balancing cylinder; 9. Z-axis guide rail; 10. Guide rail brake; 11. Y-axis ram; 12. Y-axis guide rail; 13. Middle slide; 14. X-axis guide rail; 15. X-axis linear motor; 151. First coil mounting plate; 16. Column; 17. B-axis bridge; 18. Y-axis linear motor; 181. Second coil mounting plate; 19. Z-axis linear motor; 191. Third coil mounting plate; 20. First torque motor; 21. Rotary table bearing; 22. Angle encoder; 23. Inner circumferential clamp; 24. Bushing. Detailed Implementation

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

[0032] like Figures 1-5As shown, the embodiment of the seven-axis five-linkage vertical CNC spiral bevel gear grinding machine of the present invention adopts a domestic i5 CNC system and is mainly used for grinding small module spiral bevel gears and quasi-hypoid gears. The machine tool adopts a C-type structure, including a bed 1. A hollow column 16 is provided on the top surface of the rear side of the bed 1. Two X-axis guide rails 14 arranged along the left and right directions of the bed 1 are provided on the top of the column 16, along with an X-axis linear motor 15 located between the two X-axis guide rails 14. A middle slide 13 is mounted on the surface of the two X-axis guide rails 14 via a slider. The bottom of the middle slide 13 is connected to the X-axis linear motor 15. Two horizontal Y-axis guide rails 12 perpendicular to the X-axis guide rails 14 are provided on the top of the middle slide 13, along with a middle slide 15 located between the two Y-axis guide rails 14. A Y-axis linear motor 18 is located between two Y-axis guide rails 12. A Y-axis slide 11 is mounted on the two Y-axis guide rails 12. The bottom of the Y-axis slide 11 is connected to the Y-axis linear motor 18. Two vertical Z-axis guide rails 9 and a Z-axis linear motor 19 located between the two Z-axis guide rails 9 are provided on the front end face of the Y-axis slide 11. A Z-axis slide 7 is mounted on the two Z-axis guide rails 9. The rear side of the Z-axis slide 7 is connected to the Z-axis linear motor 19. A grinding wheel electric spindle 5 parallel to the Z-axis guide rails 9 is installed inside the Z-axis slide 7. A grinding wheel is installed at the lower end of the grinding wheel electric spindle 5. X-axis linear motor 15 directly drives the middle slide plate 13, Y-axis slide 11, Z-axis slide 7, and grinding wheel electric spindle 5 to move left and right along the X-axis. Y-axis linear motor 18 directly drives the Y-axis slide 11, Z-axis slide 7, and grinding wheel electric spindle 5 to move back and forth along the Y-axis. Z-axis linear motor 19 directly drives the Z-axis slide 7 and grinding wheel electric spindle 5 to move up and down along the Z-axis. A gap of 0.8–1 mm is provided between the coils and magnetic units of the linear motors. The magnetic units can be assembled from multiple pieces according to the stroke length, and their assembly length is not limited by the stroke. A B-axis CNC rotary table 3 with its rotation axis parallel to the Y-axis guide rail 12 is installed in the middle of the column 16. The B-axis CNC rotary table 3 includes a B-axis bridge 17, and an A-axis workpiece box 2 capable of rotating the workpiece is installed in the middle of the B-axis bridge 17. The rotation axis of the A-axis workpiece box 2 is coplanar with and perpendicular to the rotation axis of the B-axis CNC rotary table 3. The Z-axis slide ram 7 is equipped with a grinding wheel electric spindle 5 that is parallel to the Z-axis guide rail 9, and a grinding wheel is installed at the lower end of the grinding wheel electric spindle 5.

[0033] This invention employs the domestically produced i5 CNC system, eliminating reliance on foreign CNC systems and resolving the bottleneck issue of core technologies. Furthermore, all three linear axes utilize direct-drive linear motors, resulting in a simpler structure compared to traditional servo motor-driven lead screw assemblies. It eliminates the need for lead screws, lead screw bearings, bearing housings, and other components, eliminating mechanical contact. A 0.8–1 mm gap exists between the coil and the magnetic unit, eliminating mechanical transmission errors and backlash. This leads to fast response speed, high positioning accuracy, and linear axis positioning accuracy is no longer affected by stroke, achieving a positioning accuracy of 0.002 mm. It also enables micro-feeds as small as 0.1 micrometers, thus enabling the processing of spiral bevel gears with a minimum module of 0.8 mm. This makes it particularly suitable for precision instruments, aerospace, robotics, automotive, and electronic equipment fields, effectively meeting the demands of the small-module spiral bevel gear processing market.

[0034] In this embodiment, the coil of the X-axis linear motor 15 is mounted at the bottom center of the middle slide plate 13 via a first coil mounting plate 151, and the magnetic unit is mounted at the top center of the column 16. This mounting structure ensures that the middle slide plate 13 is not too long due to its travel distance. Since the X-axis guide rail 14 is fixed to the top of the column, the X-axis linear motor 15 drives the middle slide plate 13 to move on the X-axis guide rail 14 via a slider. The coil of the Y-axis linear motor 18 is mounted at the top center of the middle slide plate 13 via a second coil mounting plate 181, and the magnetic unit is mounted at the bottom center of the Y-axis slide 11. The Y-axis linear motor 18 drives the Y-axis slide 11 and the Y-axis guide rail 12 to move together. The coil of the Z-axis linear motor 19 is mounted at the front end center of the Y-axis slide 11 via a third coil mounting plate 191, and the magnetic unit is mounted at the rear center of the Z-axis slide. Unlike the X-axis guide rail 14, which is fixed and the slider moves, the Y-axis guide rail 12 and the Z-axis guide rail 9 are both fixedly connected to their respective slide blocks and move together, while the corresponding guide rail sliders are fixed.

[0035] In this embodiment, the B-axis CNC rotary table 3 includes a B-axis bridge 17 located outside the column 16, a first torque motor 20, a rotary table bearing 21, an angle encoder 22, an inner circumferential clamp 23, and a stepped outer bushing 24 located inside the column 16. The bushing 24 includes a large-diameter end and a small-diameter end. For ease of installation, the large-diameter end and the small-diameter end of the bushing 24 are two independent sections, connected together by an embedded connecting bushing. The small-diameter end of the bushing 24 is supported on the column 16 by the rotary table bearing 21 and extends outward from the front end face of the column 16. The large-diameter end of the bushing 24 is connected to the first torque motor 20, a rotary table bearing 21, an angle encoder 22, an inner circumferential clamp 23, and a stepped outer bushing 24. The rotor of the first torque motor 20 is connected to the B-axis bridge 17, which is U-shaped. One end of the bridge 17 is pivotally connected to an auxiliary support mounted on the front side of the bed 1, and the other end is pivotally connected to the front end of the column 16 and connected to the small-diameter end of the bushing 24 by bolts. The first torque motor 20 directly drives the B-axis bridge 17 and the A-axis workpiece box 2 to rotate around the B-axis. An angle encoder 22 is set on the adapter spindle at the rear end of the first torque motor 20 to detect the angular displacement of the B-axis CNC rotary table 3. The inner circumferential clamp 23 is set on the outer circumference of the connecting bushing and can control the braking of the B-axis CNC rotary table 3 at any angle position within ±120°. When the B-axis CNC rotary table 3 rotates to any machining position within ±120°, the switch control valve of the inner circumferential clamp 23 quickly starts to exhaust air, quickly clamping and braking the connecting bushing before gear grinding can proceed. The inner circumferential clamp 23 is existing technology, and its specific structure and installation method will not be described in detail here. In this invention, the B-axis CNC rotary table and the A-axis workpiece box are directly driven to rotate by a torque motor built into the column, forming a cradle-like structure. This can solve the problems of low processing efficiency caused by multiple B-axis drive links and high failure rate in the prior art.

[0036] In this embodiment, the A-axis workpiece box 2 is located in the U-shaped recess of the B-axis bridge 17, directly below the grinding wheel spindle 5. It includes a workpiece spindle vertically arranged within the B-axis bridge 17, a second torque motor, and a hydraulic device for automatically tightening the workpiece. A fixture is mounted at the top of the workpiece spindle, and the workpiece is mounted on the fixture. After the fixture and workpiece are automatically tightened by the hydraulic device, the second torque motor directly drives the workpiece spindle and workpiece to rotate. The fixture and workpiece are mounted at the top of the A-axis workpiece box 2, and the direct drive by the torque motor provides backlash-free transmission, eliminating complex mechanical transmission parts and achieving high indexing accuracy. The specific structure and installation method of the A-axis workpiece box 2 are also prior art and will not be described further.

[0037] In this embodiment, a funnel-shaped chip removal groove is provided on the front side of the bed 1 directly below the B-axis bridge 17. A movable oil tank is provided directly below the chip removal groove. During machining, grinding oil and iron filings will flow directly into the oil tank below the bed 1. The oil tank is connected to a cooling temperature control filter device.

[0038] In this embodiment, a vertically arranged balancing cylinder 8 is provided on the top of the Z-axis slide 7. The balancing cylinder 8 can balance part of the load of the Z-axis assembly to reduce motor energy consumption. A temperature sensor is provided on the outer surface of the Z-axis slide 7, which can monitor the temperature rise of the grinding wheel electric spindle in real time and automatically compensate for the thermal deformation of the spindle according to the machine tool thermal deformation model established by the i5 CNC system, which can further improve the machining stability of the machine tool.

[0039] In this embodiment, a guide rail brake 10 (existing technology) is fixedly provided on the front end face of the Y-axis slide 11 to hold the Z-axis guide rail 9 and prevent the Z-axis slide 7 and the grinding wheel electric spindle 5 from falling. There are two sets of guide rail brakes, which correspond to the middle position of a Z-axis guide rail 9 respectively. The shape of the guide rail brake 10 is the same as that of the guide rail slider. A gap is provided between the guide rail brake 10 and the working surface of the Z-axis guide rail 9 for vertical movement. If the machine tool experiences a sudden power outage while running a program to process a workpiece, the i5 CNC system will trigger the Z-axis linear motor to drive the Z-axis slide 7 upwards a certain distance, causing the Z-axis slide 7 and the grinding wheel electric spindle 5 to move away from the processing area along with the grinding wheel. At the same time, the switch control valve of the guide rail brake 10 will quickly send a signal to instantly clamp the guide rail through a mechanical device, preventing the Z-axis slide 7 and the grinding wheel electric spindle 5 from falling downwards and causing the grinding wheel to collide with the workpiece and be damaged. If the machine tool experiences a sudden power outage when it is not running a processing program, the switch control valve of the guide rail brake 10 will quickly send a signal to instantly clamp the Z-axis guide rail through a mechanical device, ensuring that the Z-axis slide 7 and the grinding wheel electric spindle 5 will not fall downwards.

[0040] In this embodiment, a grinding wheel dresser 4 is provided on the left side of the front end face of the column 16. The rotation axis of the grinding wheel dresser 4 is parallel to the rotation axis of the grinding wheel electric spindle 5. The grinding wheel dresser 4 is directly driven by a high-speed electric spindle, and a diamond roller is mounted on the top of the high-speed electric spindle. When the grinding wheel needs to be dressed, the X-axis linear motor 15 drives the middle slide plate 13, Y-axis slide 11, Z-axis slide 7, grinding wheel electric spindle 5, and grinding wheel together to move quickly above the grinding wheel dresser 4, moving the grinding wheel to the dressing position of the diamond roller before dressing can be performed. The grinding wheel dresser 4 adopts a high-speed electric spindle direct drive method, which significantly improves the efficiency of dressing the grinding wheel.

[0041] In this embodiment, an online measurement system 6 is provided on the right side of the Z-axis slide 7. The measurement direction of the online measurement system 6 is parallel to the rotation axis of the grinding wheel electric spindle 5. The online measurement system 6 includes a vertically arranged piston rod, and a probe body and a ruby ​​ball probe are installed at the lower end of the piston rod. When measurement is required, the piston rod extends; after measurement, the piston rod retracts. It can automatically complete the allocation of grinding allowance and the acquisition of online measurement data.

[0042] In this embodiment, the grinding wheel electric spindle 5 is a high-speed synchronous electric spindle. The lower end of the synchronous electric spindle is equipped with an HSK A63 tool holder interface and houses a dedicated tool holder and grinding wheel. The spindle has a built-in automatic tool changer, which unloads the tool via hydraulic pressure and pulls it via pneumatic pressure. The grinding wheel electric spindle 5 assembly is equipped with an online dynamic balancing system with a balancing accuracy level of G0.4. This structure is also existing technology and will not be described further.

[0043] The seven-axis, five-linkage vertical CNC spiral bevel gear grinding machine of this invention can be expanded to include gear milling functions. The structure is interchangeable between the grinding machine and the milling machine. When the grinding machine is expanded to a milling machine, only the grinding wheel electric spindle needs to be replaced with a milling electric spindle; the milling machine does not require the installation of a grinding wheel or grinding wheel dresser.

[0044] Furthermore, any content not described in detail in this specification is existing technology known to those skilled in the art.

[0045] The above description is merely a preferred embodiment of the present invention, and the scope of protection of the present invention is not limited to the above embodiments. For those skilled in the art, improvements and modifications obtained without departing from the inventive concept should also be considered within the scope of protection of the present invention.

Claims

1. A seven-axis, five-linkage vertical CNC spiral bevel gear grinding machine tool, the machine tool adopts a C-type structure, including a bed (1), a column (16) is provided on the rear top of the bed (1), two X-axis guide rails (14) are provided on the top of the column (16), a middle slide plate (13) is slidably mounted on the X-axis guide rails (14), two horizontal Y-axis guide rails (12) perpendicular to the X-axis guide rails (14) are slidably mounted on the top of the middle slide plate (13), a Y-axis slide block (11) is mounted on the two Y-axis guide rails (12), and two vertical shafts are slidably mounted on the front end face of the Y-axis slide block (11). The Z-axis guide rail (9) has a Z-axis slide (7) mounted on the two Z-axis guide rails (9). The Z-axis slide (7) is equipped with a grinding wheel electric spindle (5) parallel to the Z-axis guide rail (9). The lower end of the grinding wheel electric spindle (5) is equipped with a grinding wheel. The column (16) has a B-axis CNC rotary table (3) with a rotation axis parallel to the Y-axis guide rail (12) mounted in the middle. The B-axis CNC rotary table (3) is equipped with an A-axis workpiece box (2) that can drive the workpiece to rotate. The rotation axis of the A-axis workpiece box (2) is in the same plane and perpendicular to the rotation axis of the B-axis CNC rotary table (3). The feature is that: The top of the column (16) is also provided with an X-axis linear motor (15) located between the two X-axis guide rails (14), and the bottom of the middle slide plate (13) is connected to the X-axis linear motor (15); the top of the middle slide plate (13) is also provided with a Y-axis linear motor (18) located between the two Y-axis guide rails (12), and the bottom of the Y-axis slide (11) is connected to the Y-axis linear motor (18); the front end face of the Y-axis slide (11) is also provided with a Z-axis linear motor (19) located between the two Z-axis guide rails (9), and the Z-axis linear motor (19) is connected to the middle slide plate (13). The rear side of the shaft slide (7) is connected to the Z-axis linear motor (19); the X-axis linear motor (15) directly drives the middle slide (13), Y-axis slide (11), Z-axis slide (7) and grinding wheel electric spindle (5) to move left and right along the X-axis direction; the Y-axis linear motor (18) directly drives the Y-axis slide (11), Z-axis slide (7) and grinding wheel electric spindle (5) to move back and forth along the Y-axis direction; the Z-axis linear motor (19) directly drives the Z-axis slide (7) and grinding wheel electric spindle (5) to move up and down along the Z-axis direction. The B-axis CNC rotary table (3) includes a B-axis bridge (17) located outside the column (16), a first torque motor (20), a rotary table bearing (21), an angle encoder (22), an inner circumferential clamp (23), and a bushing (24) located inside the column (16). The bushing (24) includes a large-diameter end and a small-diameter end that are independent of each other. The large-diameter end and the small-diameter end are connected together by an embedded connecting bushing. The small-diameter end of the bushing (24) is supported on the column (16) by the rotary table bearing (21) and extends outward from the front end face of the column (16). The large-diameter end of the bushing (24) is connected to the first torque motor (20) for rotation. The B-axis bridge (17) is U-shaped, with one end pivotally connected to the auxiliary support mounted on the front side of the bed (1) and the other end pivotally connected to the front end of the column (16) and connected to the small diameter end of the bushing (24). The first torque motor (20) directly drives the B-axis bridge (17) and the A-axis workpiece box (2) to rotate. The angle encoder (22) is set on the adapter spindle at the rear end of the first torque motor (20) to detect the angular displacement of the B-axis CNC turntable (3). The inner circumferential clamp (23) is set on the outer circumference of the connecting bushing to control the B-axis CNC turntable (3) to brake at any angle position of ±120°.

2. The seven-axis, five-linkage vertical CNC spiral bevel gear grinding machine tool according to claim 1, characterized in that: The linear motor has a gap of 0.8 to 1 mm between its coil and magnetic unit, and the magnetic unit can be assembled from multiple pieces according to the length of its stroke.

3. The seven-axis, five-linkage vertical CNC spiral bevel gear grinding machine tool according to claim 2, characterized in that: The coil of the X-axis linear motor (15) is mounted on the bottom center of the middle slide plate (13) via the first coil mounting plate (151), and the magnetic unit of the X-axis linear motor (15) is mounted on the top center of the column (16); the coil of the Y-axis linear motor (18) is mounted on the top center of the middle slide plate (13) via the second coil mounting plate (181), and the magnetic unit of the Y-axis linear motor (18) is mounted on the bottom center of the Y-axis slide (11); the coil of the Z-axis linear motor (19) is mounted on the front end face center of the Y-axis slide (11) via the third coil mounting plate (191), and the magnetic unit of the Z-axis linear motor (19) is mounted on the rear center of the Z-axis slide (7).

4. The seven-axis, five-linkage vertical CNC spiral bevel gear grinding machine tool according to claim 1, characterized in that: The top center of the Z-axis slide (7) is provided with a vertically arranged balance cylinder (8), and the outer side of the Z-axis slide (7) is provided with a temperature sensor for real-time monitoring of the temperature rise of the grinding wheel electric spindle (5).

5. The seven-axis, five-linkage vertical CNC spiral bevel gear grinding machine tool according to claim 1, characterized in that: Two sets of guide rail brakes (10) are fixed on the front end face of the Y-axis slide (11) to hold the Z-axis guide rail (9) and prevent the Z-axis slide (7) and the grinding wheel electric spindle (5) from falling. There is a gap between the guide rail brake (10) and the working surface of the Z-axis guide rail (9) for vertical movement.

6. The seven-axis, five-linkage vertical CNC spiral bevel gear grinding machine tool according to claim 1, characterized in that: The right side of the Z-axis slide (7) is provided with an online measurement system (6). The measurement direction of the online measurement system (6) is parallel to the rotation axis of the grinding wheel electric spindle (5). The online measurement system (6) includes a vertically arranged piston rod, and the lower end of the piston rod is equipped with a probe body and a ruby ​​ball probe.

7. The seven-axis, five-linkage vertical CNC spiral bevel gear grinding machine tool according to claim 1, characterized in that: A grinding wheel dresser (4) is provided on the left side of the front end face of the column (16). The rotation axis of the grinding wheel dresser (4) is parallel to the rotation axis of the grinding wheel electric spindle (5). The grinding wheel dresser (4) is directly driven by the high-speed electric spindle. A diamond roller is installed at the top of the high-speed electric spindle.

8. The seven-axis, five-linkage vertical CNC spiral bevel gear grinding machine tool according to claim 1, characterized in that: The front side of the bed (1) is provided with a funnel-shaped chip discharge groove, and a movable oil receiving tank is provided directly below the funnel-shaped chip discharge groove. The oil receiving tank is connected to a cooling temperature control filter device.

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