A fixture device for seven-axis five-linkage CNC milling of Niemann worm gears.

Abstract

A fixture device for machining Niemann worm gears using seven-axis five-linkage CNC milling includes a fixture support friction-reducing disc. An oil spraying lubrication assembly is floatingly and fixedly mounted on the upper surface of the fixture support friction-reducing disc. The lower surface of the oil spraying plate has multiple through holes. A clamping assembly is fitted onto the fixture support friction-reducing disc through these through holes, facilitating high-speed rotation around the central axis following the friction-reducing disc. A lifting column assembly is fixed to the oil spraying lubrication assembly, a tailstock support assembly is fixed to the lifting column assembly, and a circumferential limiting assembly for the oil spraying plate is fixed to the ground inside the machine tool's working chamber. This invention is used for milling Niemann series worm gears on a seven-axis five-linkage CNC machine tool, ensuring smooth side milling and preventing worm gear deformation. The adjustable length of the lifting column assembly and tailstock support assembly allows the fixture to adapt to the machining of worm gears of various geometric sizes and shapes, highlighting the adaptability and versatility of the fixture for vertical milling of worm gears.

Description

Technical Field

[0001] This invention relates to the field of machining, and specifically to a fixture device for seven-axis five-linkage CNC milling of Niemann worm gears. Background Technology

[0002] Heavy-duty Niemann worm gear drives are characterized by large transmission ratio and smooth transmission, making them suitable for applications requiring high torque and low speed. They are commonly used in industrial machinery, metallurgical mining, marine machinery, lifting and transportation, petrochemical and other fields.

[0003] The existing traditional process for machining Niemann worm gears involves first removing a large amount of material from the blank by turning, then improving the machining performance through quenching and tempering, and finally completing the semi-finishing and finishing of the tooth profile by grinding. This machining process involves multiple clamping and unclamping operations, and most of the grinding machines used are custom-made special-purpose machines.

[0004] Therefore, existing processing methods face problems such as the need for specialized machine tools, low versatility, and the impact of centering and positioning errors caused by multiple clamping of the workpiece during processing on the accuracy of the tooth profile and low processing efficiency, which need to be further solved and optimized. Summary of the Invention

[0005] Purpose of the invention:

[0006] To address the unavoidable issues of secondary clamping and inconsistent precision in traditional processes, this technical solution provides a fixture device for seven-axis five-linkage CNC milling of Niemann worm gears. By utilizing a single seven-axis five-linkage milling machining center, all machining processes on the tooth surface of the heavy-duty Niemann worm gear are completed in a single clamping operation, from roughing to finishing. This significantly improves machining efficiency and precision, ultimately reducing production costs for enterprises and effectively solving the aforementioned problems.

[0007] This invention is achieved through the following technical solution:

[0008] A fixture device for seven-axis five-linkage CNC milling of Niemann worm gears includes a fixture support friction-reducing disc, an oil spraying lubrication assembly, a clamping assembly, a lifting column assembly, a tailstock support assembly, and an oil spray plate circumferential limiting assembly. The oil spraying lubrication assembly is located on the upper surface of the fixture support friction-reducing disc and is floating and relatively fixed. The fixture support friction-reducing disc has a through hole, through which the clamping assembly is sleeved on the fixture support friction-reducing disc to facilitate high-speed rotation around the central axis following the fixture support friction-reducing disc. The lifting column assembly is fixed to the oil spraying lubrication assembly, the tailstock support assembly is fixed to the lifting column assembly, and the oil spray plate circumferential limiting assembly is fixed to the ground inside the machine tool working chamber.

[0009] This fixture allows the workpiece to be placed vertically, perpendicular to the tool's spindle. The workpiece rotates with the worktable, while the fixture body remains stationary in a set position, preventing collisions with the tool and thus avoiding machining accidents. Furthermore, the fixture can use a hydraulic system and an electric motor to control the moving parts to hold worm gears of different lengths, enabling efficient milling of worm gears. This fixture is suitable for milling Niemann worm gears on seven-axis, five-linkage CNC machine tools, as well as for machine-clamped machining requirements of Niemann worm gears of various geometric shapes and sizes.

[0010] Furthermore, the upper surface of the clamp support friction reducing disc is provided near the outer diameter with an oil return channel for collecting the thin oil sprayed by the oil injection lubrication assembly, and a large-diameter oil discharge port is provided on the side ring surface of the clamp support friction reducing disc. An oil pipe is connected to the oil discharge port to guide the oil into the oil tank. The oil pipe connected to the oil discharge port to guide the oil into the oil tank facilitates the circulation and use of the oil.

[0011] Furthermore, the oil injection lubrication assembly has several cylindrical strip channels evenly spaced at equal angles at a certain depth from the lower surface. The lower surface of the oil injection lubrication assembly has multiple regular hexagonal holes corresponding to the cylindrical strip channels. Each regular hexagonal hole is equipped with a direct injection nozzle of the oil injection device. The long strip channel is equipped with an oil delivery pipe and connected to the direct injection nozzle. During operation, the oil injection lubrication assembly, the lifting column assembly, and the tail support assembly float on the clamp support friction reduction disc.

[0012] Furthermore, the thin oil injection in the oil injection lubrication assembly is achieved by a hydraulic system. The thin oil pump, primary distributor, secondary distributor, safety valve, high-pressure filter, cooler, relief valve, check valve, flow meter, and filter in the hydraulic system control the nozzles in the oil injection lubrication assembly to inject thin oil. The hydraulic system circuit can also be arranged in other ways to achieve the working control of the oil injection lubrication assembly.

[0013] Furthermore, the clamping assembly is a large-diameter four-jaw clamping chuck, which is convenient to meet the clamping requirements for machining large-diameter worm gears and is fixed on the clamping base; the clamping assembly can also be other clamping devices that can clamp cylindrical rods.

[0014] Furthermore, the lifting column assembly consists of two parts, upper and lower. The lower part of the lifting column assembly is fixed to the base of the lifting column assembly, used to fix the lifting column assembly to the oil spraying lubrication assembly. The base of the lifting column assembly is evenly provided with six reinforcing ribs, which are fixedly connected to a hollow cylinder of a certain thickness. One side of the hollow cylinder has a long strip-shaped through groove with arc-shaped ends, and the outer surface is provided with a horseshoe-shaped fixing device. The upper part of the lifting column assembly has a spring-like pin device at a certain height on its inner wall. The upper and lower parts slide together and use the spring-like pin device to form a lifting column assembly with an adjustable positioning height. The lower column of the lifting column assembly is provided with a circumferential limiting support groove, which cooperates with the axial limiting component of the oil spraying plate.

[0015] Furthermore, the tailstock support assembly includes: a tailstock support assembly housing, a support base, and an internal transmission mechanism; the internal transmission mechanism is mainly formed by a worm gear pair transmission, with a shoulder, a deep groove ball bearing, a washer, and a bearing end cap symmetrically mounted on the central shaft of the worm, and fixed to the two side walls of the tailstock support assembly housing; the worm gear is mounted on the lead screw by a lead screw nut and a lead screw shaft; the lead screw nut restricts the rotation of the worm gear and only allows for vertical translational movement; the upper and lower walls of the tailstock support assembly housing have through holes, through which the lead screw passes; a split locking nut assembly is installed on the lead screw passing through the lower wall, with a small gap in the middle of the locking nut assembly forming upper and lower thread locking with the lead screw thread respectively, and bolts are used to lock the nuts in multiple through holes on the two locking nuts; the ejector pin is fixed to the lower end of the lead screw.

[0016] Furthermore, the movement of the worm gear pair in the tailstock support assembly is achieved by a three-phase asynchronous motor, which is controlled by a PLC to realize the sequential operation of the motor in the forward-stop-reverse direction. The motor is connected to the worm shaft through a coupling to transmit motion. In addition to motor drive, other drive methods can also be used.

[0017] Furthermore, the circumferential limiting assembly of the fuel injector plate includes: an outer housing, a hydraulic cylinder device, an extendable arm-shaped assembly, a ball-shaped column assembly, and a base plate; a set of hydraulic cylinder devices is fixed to the outer housing and the base plate via hydraulic cylinder bases; the ball-shaped column assembly is connected to the piston rod of the hydraulic device via a coupling; the extendable arm-shaped assembly consists of an extendable arm and an external claw-shaped body, and the extendable arm-shaped assembly is fixed to the ball-shaped column assembly via left and right end caps; the external claw-shaped body consists of a disc, a disc cross pin, and... The cross pin consists of nuts at both ends, and the external claw-like body restricts the lifting column and the oil-spraying base plate from rotating with the clamping support friction-reducing disc. During side milling, considering the bending of the workpiece caused by the milling force of the tool acting on it, the external claw-like body structure can apply a certain force. The position of the extended arm-like component can be adjusted by adjusting the hydraulic cylinder device to meet the requirements of machining worm gears of different lengths. The outer housing base is fixed to the ground inside the machine tool working chamber, and its fixed position is on one side of the machine tool worktable and arranged at a 45° angle to the machine tool tool holder.

[0018] Furthermore, the hydraulic cylinder device in the circumferential limiting assembly of the fuel injector plate has its movement controlled by a hydraulic system. The hydraulic system comprises an oil tank, a pressure-limiting variable pump, a check valve, a three-position five-way solenoid directional valve, a two-position three-way solenoid directional valve, a hydraulically controlled check valve, a speed control valve, a relief valve, a back pressure valve, a pressure relay, a time relay, a filter, and hydraulic cylinder components, forming a speed control circuit, a pump oil supply circuit, a rapid circuit, a speed switching circuit, a directional circuit, and a pressure control circuit. This enables the hydraulic cylinder to achieve a "rapid advance—working advance—dwell—rapid retraction—stop" work cycle. The arrangement of the hydraulic system circuit can also employ other methods to achieve motion control of the hydraulic cylinder. Beneficial effects

[0019] The present invention proposes a fixture device for seven-axis five-linkage CNC milling of Niemann worm gears, which has the following advantages compared with the prior art:

[0020] This invention relates to a fixture and fixture assembly for milling heavy-duty Niemann worm gears on a seven-axis, five-linkage CNC machine tool. The fixture operates under hydraulic system control and an electric motor control. Specifically, the fixture assembly clamps Niemann worm gear blanks with different length-to-diameter ratios and applies forces in multiple directions to the circumferential limiting assembly of the oil spray plate to prevent the lifting column assembly and oil spray lubrication assembly from rotating. Simultaneously, based on the length-to-diameter ratio of the pre-machined worm gear blank and its stress analysis, the height of the extended arm of the circumferential limiting assembly of the oil spray plate is adjusted to apply a certain force to the lifting column assembly, thereby preventing worm gear deformation during side milling, improving machining accuracy, and meeting machining requirements. This satisfies the requirements of a seven-axis, five-linkage CNC machine tool for efficient worm gear machining and clamping Niemann worm gears of different geometric shapes and sizes.

[0021] This invention drives the friction-reducing disc of the clamping fixture to rotate, causing the clamping assembly fixed on it to drive the workpiece to rotate coaxially. The tailstock support assembly cooperates with the clamping assembly, thereby ensuring the control of machining errors such as deflection of the clamped workpiece during side milling. The circumferential limiting assembly of the oil spray plate cooperates with the oil spraying lubrication assembly to prevent the column lifting assembly and the tailstock support assembly fixed on the oil spraying fixture assembly from rotating, thereby ensuring that collisions with the tool are avoided during side milling and preventing production accidents. The circumferential limiting assembly of the oil spray plate cooperates with the lifting column assembly to apply a certain force to the workpiece during side milling, acting as a simple-supported beam, thereby preventing bending deformation of the workpiece and ensuring machining accuracy. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the fixture of the present invention.

[0023] Figure 2 This is a front view of the fixture of the present invention.

[0024] Figure 3 This is a structural diagram and a cross-sectional view along line AA of the clamp support friction-reducing disc of the present invention.

[0025] Figure 4 These are the isometric side view and left view of the oil spraying lubrication assembly of the present invention.

[0026] Figure 5 This is another perspective structural diagram and CC line cross-sectional view of the oil injection lubrication assembly of the present invention.

[0027] Figure 6 These are structural diagrams, DD-line sectional views, and bottom views of the lifting column assembly of the present invention.

[0028] Figure 7 This is an isometric view of the tailstock support assembly of the present invention.

[0029] Figure 8 This is a front view and a partial enlarged view of the tailstock support assembly of the present invention.

[0030] Figure 9 yes Figure 8 EE line sectional view of the tailstock support assembly.

[0031] Figure 10 This is a schematic diagram and a partial enlarged view of the circumferential limiting component of the fuel injector plate of the present invention.

[0032] Figure 11 This is a front view and a BB line sectional view of the circumferential limiting component of the spray plate of the present invention.

[0033] Figure 12 This is a simplified force analysis diagram of the circumferential limit component for setting the fuel injector.

[0034] Figure 13 This is a schematic diagram of the hydraulic system control of the clamp of the present invention.

[0035] Figure 14 This is a schematic diagram of the motor operation control of the clamp of the present invention.

[0036] Figure 15 This is a schematic diagram of the thin oil control system of the oil spraying lubrication component of the clamp of the present invention.

[0037] The labels in the attached diagram are as follows: 100-clamp body, 1-machine tool worktable, 2-worm gear for clamping workpiece, 10-clamp support friction reducing plate, 11-clamp support friction reducing plate oil return channel, 12-clamp support friction reducing plate oil return hole, 20-oil injection lubrication assembly, 21-oil injection lubrication assembly and lifting column assembly assembly threaded hole 1, 22-oil injection lubrication assembly and lifting column assembly assembly threaded hole 2, 23-oil injection lubrication assembly oil supply channel, 24-oil injection lubrication assembly oil pipe connection pipe, 25-oil injection lubrication assembly nozzle mounting hole, 250-oil injection lubrication assembly nozzle, 251-nozzle front nozzle, 252-nozzle Oil supply port, 30-clamping assembly, 40-tailstock support assembly, 41-tailstock support assembly housing, 42-tailstock support assembly motor, 43-tailstock support assembly connecting bracket, 44-connecting bracket reinforcing rib, 45-tailstock support assembly connecting bracket positioning threaded hole, 46-top connecting part of ejector pin, 47-ejector pin, 480-coupling, 490-washer, 50-lifting column assembly, 51-upper column of lifting column assembly, 52-lower column of lifting column assembly, 53-upper column connecting bracket, 54-upper column connecting bracket positioning threaded hole, 55-lower column channel, 56-lower... 57-Lower column base reinforcing rib; 58-Lifting column assembly locking ring; 59-Upper column spring body; 591-Upper column spring telescopic rod; 592-Circumferential limit support groove; 500-Deep groove ball bearing; 510-Shoulder; 520-Lead screw top seat; 530-Tail frame support assembly upper fixing device; 540-Lead screw nut; 550-Worm gear pair; 560-Lower locking nut; 561-Upper locking nut; 562-Locking nut assembly fixing through hole; 570-Lead screw; 580-Bearing end cover; 590-Locking nut assembly; 595-Top connecting component. 60-Circumferential limiting assembly for fuel injector plate; 61-Extended arm of circumferential limiting assembly for fuel injector plate; 62-Spherical column of circumferential limiting assembly for fuel injector plate; 63-Housing shell of circumferential limiting assembly for fuel injector plate; 64-Base plate of circumferential limiting assembly for fuel injector plate; 65-External claw-shaped body of spherical column; 66-Disc of external claw-shaped body; 67-Horizontal pin of external claw-shaped body disc; 68-Nuts at both ends of horizontal pin of external claw-shaped body disc; 69-Right end cap of spherical column; 70-Left end cap of spherical column; 71-Upper coupling of spherical column; 72-Upper coupling of hydraulic cylinder piston; 73-Hydraulic cylinder; 74-Base of hydraulic cylinder. Detailed Implementation

[0038] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments. The described embodiments are merely some embodiments of the present invention, and not all embodiments. Various modifications and improvements made to the technical solutions of the present invention by those skilled in the art without departing from the design concept of the present invention should fall within the protection scope of the present invention. Example 1

[0039] like Figures 1 to 11 As shown, a fixture device for seven-axis five-linkage CNC milling of Niemann worm gears includes a fixture support friction reduction disc 10, an oil spraying lubrication assembly 20, a clamping assembly 30, a lifting column assembly 50, a tailstock support assembly 40, and an oil spraying plate circumferential limiting assembly 60.

[0040] Specifically, the oil spraying lubrication assembly 20 is located on the upper surface of the clamp support friction-reducing disc 10 and is floating and relatively fixed. The clamp support friction-reducing disc 10 is provided with a through hole, and the clamping assembly 30 is sleeved on the clamp support friction-reducing disc 10 through the through hole to facilitate high-speed rotation around the central axis with the clamp support friction-reducing disc 10. The lifting column assembly 50 is connected and fixed to the oil spraying lubrication assembly 20 through a threaded hole, and the tailstock support assembly 40 is connected and fixed to the lifting column assembly 50 through bolts. The oil spray plate circumferential limiting assembly 60 is fixed to the ground surface of the machine tool working chamber by screws. By driving the clamp support friction-reducing disc 10 to rotate, the clamping assembly fixed on it is... The 30 drives the workpiece to rotate coaxially. The tailstock support assembly 40 cooperates with the clamping assembly 30 to ensure the control of machining errors such as deflection of the clamped workpiece during side milling. The oil spray plate circumferential limiting assembly 60 cooperates with the oil spray lubrication assembly 20 to prevent the lifting column assembly 50 and the tailstock support assembly 40 fixed on the oil spray fixture assembly 20 from rotating together, thereby ensuring that collisions with the tool are avoided during side milling and production accidents are prevented. The oil spray plate circumferential limiting assembly 60 cooperates with the lifting column assembly 50 to provide a certain force during side milling, acting as a simple supported beam to prevent bending deformation of the workpiece and ensure machining accuracy.

[0041] like Figure 3 The diagram shows a schematic of the clamp support friction reducing disc 10. Near the outer diameter of the upper surface of the clamp support friction reducing disc 10, there is an oil return annular groove 11 for collecting the thin oil sprayed from the oil injection lubrication assembly and for floating it above the clamp support friction reducing disc. Also, a large-diameter oil discharge and return hole 12 is provided on the side annular surface of the clamp support friction reducing disc, through which oil is introduced into the oil tank via an oil pipe for convenient oil circulation and use.

[0042] like Figures 4 to 5As shown, several cylindrical strip-shaped channels are evenly spaced at equal angles at a certain depth from the lower surface of the oil injection lubrication assembly 20, serving as oil delivery channels 23. Several regular hexagonal holes corresponding to the cylindrical strip-shaped channels are opened on the lower surface of the oil injection lubrication assembly 20, serving as nozzle mounting holes 25. A direct injection nozzle 250 of the oil injection device is installed in each regular hexagonal nozzle mounting hole 25. An oil delivery pipe 24 is installed in the long strip-shaped channel and connected to the direct injection nozzle 250, forming an effective device that allows the oil injection lubrication assembly 20, the lifting column assembly 50 fixed thereon, and the tail support assembly 40 to float on the clamp support friction reduction disc during operation.

[0043] like Figure 1 As shown, the clamping assembly 30 is fixed on the clamping support friction reduction plate 10. It is a large-diameter four-jaw clamping chuck, which is convenient to meet the clamping requirements of machining large-diameter worm gears. The clamping assembly 30 is not limited to the four-jaw chuck clamping used in this paper, but can also be other clamping cylindrical rods.

[0044] like Figure 6 As shown, the lifting column assembly 50 consists of two parts, upper and lower. The lower half 52 of the lifting column assembly has a base that is fixed to the oil spraying lubrication assembly 20 through a positioning threaded hole 54 for connecting the bracket body. The base 57 is evenly provided with six reinforcing ribs 56 and is fixedly connected to a hollow circular column of a certain thickness. The hollow circular column has a long strip-shaped through groove 55 with arc ends on one side and a horseshoe-shaped fixing device locking ring 58 on the outer surface. The upper half 51 of the lifting column assembly has a spring-like pin device spring body 59 and a spring telescopic rod 591 at a certain height on its inner wall. The upper and lower parts slide together and use the spring-like pin to form a lifting column assembly 50 with an adjustable positioning height. The lower column 52 of the lifting column assembly is provided with a circumferential limiting support groove 592, which cooperates with the circumferential limiting assembly 60 of the oil spray plate.

[0045] like Figures 7 to 9As shown, the tailstock support assembly 40 consists of a tailstock support assembly housing 41, a support base 43, and an internal transmission mechanism. The internal transmission mechanism is mainly formed by worm gear transmission. The worm shaft is symmetrically equipped with a shoulder 510, a deep groove ball bearing 500, a washer 490, and a bearing end cap 580, and is fixed to the two side walls of the tailstock support assembly housing. The worm gear is mounted on the lead screw 570 by a lead screw nut 540 cooperating with the lead screw shaft. The lead screw nut 540 restricts the rotation of the worm gear and only allows for translational movement. The upper and lower walls of the tailstock support assembly housing 41 are provided with through holes, through which the lead screw 570 passes. A split locking nut assembly 590 is installed on the lead screw passing through the lower wall. The locking nut assembly 590 is divided into an upper locking nut 561 and a lower locking nut 560, with a small gap in between to form upper and lower locking with the lead screw thread, respectively. The locking effect is achieved by bolts in the multiple through holes 562 opened on the two locking nuts. The ejector pin 47 is fixed to the lower end of the lead screw.

[0046] like Figures 10 to 11 As shown, the circumferential limiting assembly 60 of the fuel injector plate consists of an outer housing 63, a hydraulic cylinder device 73, an outward-extending arm-shaped assembly 61, a ball-headed column assembly 62, and a base plate 64. A set of hydraulic cylinder devices 73 is fixed to the assembly housing 63 and the base plate 64 via hydraulic cylinder bases 74. The ball-headed column assembly 62 is connected to the piston rod of the hydraulic device 73 via couplings 71 and 72. The outward-extending arm-shaped assembly 61 consists of an outward-extending arm and an external claw-shaped body 65, and is fixed to the ball-headed column assembly 62 via left 70 and right 69 end caps. The external claw-shaped body 65 is composed of a disc... 66. The disc cross pin 67 and the nuts 68 at both ends of the cross pin constitute a structure. The external claw-shaped body 65 restricts the lifting column 50 and the oil spray lubrication assembly 20 from rotating with the clamp support friction reduction disc 10. During side milling, the bending tendency of the workpiece caused by the milling force of the tool acting on the workpiece is taken into account, and the external claw-shaped body 65 structure can apply a certain force. The position of the extended arm-shaped assembly 61 can be adjusted by adjusting the hydraulic cylinder device 73 to meet the requirements of worm gear processing of different lengths. The outer housing base 64 is fixed on the ground of the machine tool working chamber, and its fixed position is on one side of the machine tool worktable and arranged at a 45° angle with the machine tool tool post.

[0047] like Figure 12 As shown, during side milling, if the circumferential limiting component 60 of the oil spray plate is not set, a simplified force analysis of the worm gear blank 2 is performed, and it is subjected to F x F y The force F2 lacks a horizontal force to balance it; however, when the circumferential limiting component 60 of the fuel injector plate is set, the force analysis of the worm gear blank 2 is simplified again, and it is subjected to F x F yThe forces F1 and F2 can bring the entire structure into a state of force balance, so a circumferential limiting component 60 for the oil spray plate is required. When the length-to-diameter ratio L / D of the worm gear to be processed is greater than 20, it is a slender rod, and attention needs to be paid to its bending deformation. The deformation of the worm gear is prevented by adjusting the position of the ball-shaped column of the circumferential limiting component of the oil spray plate. That is, the value of L1 in the schematic diagram is changed, and the position of the ball-shaped column is estimated by performing a force analysis based on the magnitude of the milling force, thereby improving the machining accuracy to meet the actual requirements.

[0048] like Figures 7 to 9 , Figure 14 As shown, the movement of the worm gear pair in the tailstock support assembly 40 is achieved by a three-phase asynchronous motor 42. The motor operates in a forward-stop-reverse sequence through PLC control. The motor 42 is connected to the worm shaft 570 via a coupling 480 to transmit motion. In addition to motor drive, other drive methods can also be used.

[0049] Of course, in addition to the aforementioned electric motor-controlled worm gear pair motion mechanism and hydraulic system-controlled transmission mechanism, the transmission mechanism of the tailstock support assembly and the circumferential limit assembly of the fuel injector plate can also adopt a combination of various existing transmission mechanisms and drive methods, which will not be elaborated further.

[0050] like Figure 13 As shown, the circumferential limiting assembly 60 of the fuel injection plate has a hydraulic system that controls the movement of the hydraulic cylinder. This system comprises components such as an oil tank, a pressure-limiting variable pump, a check valve, a three-position five-way solenoid valve, a two-position three-way solenoid valve, a hydraulically controlled check valve, a speed control valve, a relief valve, a back pressure valve, a pressure relay, a time relay, a filter, and the hydraulic cylinder. These components form a speed control circuit, a pump oil supply circuit, a rapid circuit, a speed switching circuit, a reversing circuit, and a pressure control circuit, enabling the hydraulic cylinder to achieve a "rapid advance—working advance—dwell—rapid retraction—stop" work cycle. The hydraulic system circuit can also be arranged in other ways to control the movement of the hydraulic cylinder.

[0051] like Figure 15 As shown, the spraying operation of the nozzle 250 of the oil injection lubrication assembly 20 is realized by a hydraulic system. The system controls the spraying of high-pressure thin oil by the nozzle 250 of the oil injection lubrication assembly 20 through components such as a thin oil pump, a primary distributor, a secondary distributor, a safety valve, a high-pressure filter, a cooler, a relief valve, a check valve, a flow meter, and a filter. The hydraulic system circuit can also be arranged in other ways to realize the operation control of the oil injection lubrication assembly.

[0052] like Figures 1 to 11As shown, the specific process of this fixture device is as follows: First, the circumferential limiting component 60 of the spray plate is fixed on one side of the machine tool worktable 1 and arranged at a 45° angle with the machine tool tool post; second, the remaining fixture device parts are connected to the machine tool worktable 1 in a coaxial position with the maximum stroke position; then, one end of the worm gear blank 2 to be processed is clamped on the four-jaw chuck of the clamping device; then, the position of the upper column 51 of the lifting column assembly 50 is adjusted so that the distance between the ejector pin 47 clamped on the tailstock support assembly 40 and the pre-drilled hole on the other end face of the worm gear blank 2 is small, and the adjustment is in accordance with the requirements. The locking ring 58 is required to be tightened to secure the lifting column assembly 50. At this time, the hydraulic system is powered on, and oil is pumped from the cylinder through the hydraulic pump. Under the control of the hydraulic system, the hydraulic cylinder 73 works to drive the ball-shaped column 62 of the circumferential limiting assembly of the fuel injector plate to a preset certain height position. At this time, the extended arm 61 in the circumferential limiting assembly of the fuel injector plate cooperates with the circumferential limiting support groove 592 on the lower column 52 to apply a certain horizontal force, thereby forming a support state similar to a simply supported beam. The cooperation of multiple components causes the circumferential limiting assembly 60 of the fuel injector plate to move to the preset height position. Normal operation; then control the motor 42 in the tailstock support assembly 40 to work, and through the transmission device, move the ejector pin 47 into the pre-drilled hole at one end of the worm gear blank 2. After reaching the target position, the locking nut assembly 590 is used to fix the working position of the lead screw 570. Open the oil supply device in the control oil spraying lubrication assembly 20, and control the oil to spray out from multiple sets of nozzles 250 so that the oil spraying lubrication assembly 20 and above of the fixture device are suspended from the base 10, thereby ensuring that they do not rotate together with the machine tool worktable 1 and the fixture support friction reduction plate. The oil sprayed from the nozzles 250 returns to the base through the oil return channel. The oil return hole 11 and the oil return hole 12 return to the oil tank to achieve the function of recycling and prevent oil leakage from contaminating the processing environment. In general, it is necessary to keep one end of the worm gear clamped and rotated and its own coaxiality, prevent the lifting column assembly 50 from tipping over, prevent the oil spraying and lubrication assembly 20 from rotating, and avoid tool collision, etc. After the worm gear is processed, first control the oil supply device in the oil spraying and lubrication assembly 20 to stop the oil supply, and the oil spraying and lubrication assembly 20 contacts the clamp support friction reduction plate 10. Through the control of the hydraulic system, each working hydraulic cylinder is reset and unloaded. Finally, the processed workpiece is unloaded to complete the entire processing process.

[0053] like Figure 13As shown in the schematic diagram, a brief analysis of the hydraulic system's operation is as follows: Before rapid advance, all control valves are in the neutral or normal position. During rapid advance, 1YA is energized, connecting the three-position five-way valve 5 to the left position; 3YA is energized, connecting the two-position three-way valve 11 to the right position, creating pressure at the control port of the pilot-operated check valve 10. This opens the pilot-operated check valve, preventing oil from flowing through the speed control valve 9, thus achieving rapid advance. During working advance, 1YA is energized, connecting the three-position five-way valve 5 to the left position. In the return oil path, oil cannot flow through the pilot-operated check valve 10, so 3YA of the two-position three-way valve 11 must be de-energized. Oil returns from the speed control valve 9 to the oil tank, stabilizing and regulating the speed, thus achieving working advance. During pause, when the pressure in the hydraulic cylinder reaches the preset value, the pressure relay 6 activates the directional valve 5 to the neutral position. The time relay maintains the current state for a period of time, achieving pause. During rapid retraction, the time relay triggers the electromagnetic action of directional valve 5, i.e., 1YA is de-energized and 2YA is energized, thus achieving the rapid retraction action. At this time, directional valve 11 prepares for entering the next cycle, so de-energizing 2YA returns directional valve 11 to its normal position. When stopping, all electromagnets are de-energized, all directional valves are reset, and the hydraulic pump is unloaded, completing the stopping action.

[0054] like Figure 15 As shown in the schematic diagram, a brief analysis of the fuel injection system's operation is as follows: The fuel injection system is driven by a thin oil pump 1. The oil is filtered and cooled by a high-pressure filter 10 and a cooler 11. Then, the oil is distributed as needed by the primary distributor 2 to the respective distributor motors of the secondary distributors 3, 4, 5, 6, 7, and 8, causing the thin oil to be sprayed from each injector. This cycle repeats continuously. When the oil pressure in the system exceeds the set pressure, it is released through the safety valve 9.

[0055] The above-described embodiments are merely preferred embodiments provided to fully illustrate the present invention, and the scope of protection of the present invention is not limited thereto. Equivalent substitutions or modifications made by those skilled in the art based on the present invention are all within the scope of protection of the present invention. The scope of protection of the present invention is defined by the claims.

Claims

1. A fixture device for seven-axis five-linkage CNC milling of Niemann worm gears, characterized in that: It includes a clamp support friction reducing plate (10), an oil spraying lubrication assembly (20), a clamping assembly (30), a lifting column assembly (50), a tailstock support assembly (40), and an oil spray plate circumferential limiting assembly (60); the oil spraying lubrication assembly (20) is located on the upper surface of the clamp support friction reducing plate (10) and is relatively fixed while floating; The clamping support friction reducing plate (10) is provided with a through hole, and the clamping assembly (30) is sleeved on the clamping support friction reducing plate (10) through the through hole, so as to follow the clamping support friction reducing plate (10) to rotate at high speed around the central axis; the lifting column assembly (50) is fixed on the oil spraying lubrication assembly (20), the tailstock support assembly (40) is fixed on the lifting column assembly (50), and the oil spray plate circumferential limiting assembly (60) is fixed on the ground of the machine tool working chamber; The lifting column assembly (50) consists of two parts, upper and lower. The lower half of the lifting column assembly (50) is fixed on the lifting column assembly base (57) to fix the lifting column assembly (50) to the oil spraying lubrication assembly (20). The lifting column assembly base (57) is evenly provided with six reinforcing ribs and is fixedly connected to a hollow cylinder of a certain thickness. The hollow cylinder has a long strip-shaped through groove with arc ends on one side and a horseshoe-shaped fixing device on the outer surface. The upper half of the lifting column assembly has a spring pin device on its inner wall. The upper and lower parts slide together and use the spring pin device to form a lifting column assembly (50) with a changeable positioning height. The lower column (52) of the lifting column assembly (50) is provided with a circumferential limiting support groove, which cooperates with the circumferential limiting assembly (60) of the oil spray plate. The tailstock support assembly (40) includes: a tailstock support assembly housing (41), a support base, and an internal transmission mechanism; the internal transmission mechanism is formed by a worm gear pair transmission, and a shoulder (510), a deep groove ball bearing (500), a washer (490), and a bearing end cap (580) are symmetrically mounted on the central shaft of the worm gear, and are fixed to the two side walls of the tailstock support assembly housing (41); the worm gear is mounted on the lead screw by a lead screw nut and a lead screw shaft; the lead screw nut restricts the rotation of the worm gear and only allows for vertical translational movement; the upper and lower walls of the tailstock support assembly housing (41) are provided with through holes, and the lead screw passes through the through holes; a split locking nut assembly is installed on the lead screw passing through the lower wall, and the locking nut assembly has a small gap in the middle to form upper and lower locking with the lead screw thread respectively, and uses bolts to form a locking effect in multiple through holes on the two locking nuts, and a pin is fixed to the bottom end of the lead screw.

2. The fixture device for seven-axis five-linkage CNC milling of Niemann worm gears according to claim 1, characterized in that: The upper surface of the clamp support friction reducing disc (10) near the outer diameter is provided with an oil return channel (11) for collecting the thin oil sprayed by the oil spraying lubrication assembly (20), and a large-diameter oil discharge port is provided on the side ring surface of the clamp support friction reducing disc (10), and an oil pipe is connected to the oil discharge port to guide the oil into the oil tank.

3. The fixture device for seven-axis five-linkage CNC milling of Niemann worm gears according to claim 1, characterized in that: The oil spraying lubrication assembly (20) has several cylindrical strip channels evenly spaced at equal angles at a set distance from the lower surface. The lower surface of the oil spraying lubrication assembly (20) has multiple regular hexagonal holes corresponding to the cylindrical strip channels. Each regular hexagonal hole is equipped with a direct injection nozzle (250) of the oil spraying device. The cylindrical strip channels are equipped with oil supply pipes and connected to the direct injection nozzles (250). During operation, the oil spraying lubrication assembly (20), the lifting column assembly (50), and the tail support assembly (40) float on the clamp support friction reduction disc (10).

4. A fixture device for seven-axis five-linkage CNC milling of Niemann worm gears according to claim 3, characterized in that: The thin oil injection in the oil injection lubrication assembly (20) is achieved by a hydraulic system. The thin oil pump, primary distributor, secondary distributor, safety valve, high pressure filter, cooler, overflow valve, check valve, flow meter and filter in the hydraulic system control the nozzles in the oil injection lubrication assembly to inject thin oil.

5. A fixture device for seven-axis five-linkage CNC milling of Niemann worm gears according to claim 1, characterized in that: The clamping assembly (30) is a large-diameter four-jaw clamping chuck, which is fixed on the clamp support friction-reducing disc (10).

6. A fixture device for seven-axis five-linkage CNC milling of Niemann worm gears according to claim 1, characterized in that: The movement of the worm gear pair in the tailstock support assembly (40) is achieved by a three-phase asynchronous motor. The motor is controlled by a PLC to achieve the sequential operation of forward rotation-stop-reverse rotation. The motor is connected to the central shaft of the worm through a coupling to transmit motion.

7. A fixture device for seven-axis five-linkage CNC milling of Niemann worm gears according to claim 1, characterized in that: The circumferential limiting assembly (60) of the fuel injector plate includes: an outer shell (63), a hydraulic cylinder device, an outstretched arm-shaped assembly (61), a ball-shaped column assembly (62), and a base plate; a set of hydraulic cylinder devices is fixed to the outer shell and the base plate through a hydraulic cylinder base; the ball-shaped column assembly (62) is connected to the piston rod of the hydraulic cylinder device through a coupling; the outstretched arm-shaped assembly (61) is composed of an outstretched arm and an external claw-shaped body, and the outstretched arm-shaped assembly is fixed to the ball-shaped column assembly (62) through the left and right end caps in the ball-shaped column assembly (62); The external claw-shaped body consists of a disc, a disc cross pin, and nuts at both ends of the cross pin. The external claw-shaped body restricts the lifting column assembly from rotating with the clamping support friction-reducing disc. During side milling, considering the bending of the workpiece caused by the milling force of the tool acting on the workpiece, the external claw-shaped body structure can apply a certain force. The position of the extended arm-shaped assembly can be adjusted by adjusting the hydraulic cylinder device, which can meet the requirements of worm gear processing of different lengths. The base of the external housing (63) is fixed on the ground of the machine tool working chamber, and its fixed position is on one side of the machine tool worktable and arranged at a 45° angle with the machine tool tool holder.

8. A fixture device for seven-axis five-linkage CNC milling of Niemann worm gears according to claim 7, characterized in that: The hydraulic cylinder device in the circumferential limiting assembly (60) of the oil injection plate is moved by the hydraulic system. The hydraulic cylinder is moved by the hydraulic system. The oil tank, pressure-limiting variable pump, check valve, three-position five-way solenoid directional valve, two-position three-way solenoid directional valve, hydraulic control check valve, speed regulating valve, overflow valve, back pressure valve, pressure relay, time relay, filter, and hydraulic cylinder components form a speed regulating circuit, oil supply circuit, fast circuit, speed switching circuit, directional circuit and pressure control circuit, so that the hydraulic cylinder realizes the working cycle of "fast advance - working advance - pause - fast retreat - stop".

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