Slow wire electrical discharge wire cutting wire control device

Abstract

The present application relates to the technical field of slow wire cutting machining equipment, and particularly relates to a slow wire cutting machining device for wire cutting electrical discharge machining. The slow wire cutting machining device for wire cutting electrical discharge machining comprises a support, a wire guide mechanism and a tension adjusting mechanism. The wire guide mechanism is arranged on the support and is used for conveying an electrode wire. The tension adjusting mechanism is arranged on the support. The tension adjusting mechanism comprises a plurality of smooth guide wheels, the plurality of smooth guide wheels are connected through a tension belt drive, a magnetic powder controller, an output end of the magnetic powder controller is connected with one of the smooth guide wheels, the electrode wire is clamped between the tension belt and one of the smooth guide wheels, the magnetic powder controller controls the braking torque acting on the smooth guide wheel by adjusting the excitation current, and the braking torque acts on the electrode wire through the tension belt to generate controllable tension. The slow wire cutting machining device for wire cutting electrical discharge machining realizes accurate and controllable adjustment of the electrode wire tension, and improves the stability and precision of the cutting machining.

Description

Technical Field

[0001] This invention relates to the technical field of slow wire EDM equipment, and in particular to a slow wire EDM wire cutting control device. Background Technology

[0002] Wire EDM (Electrical Discharge Machining) is a high-precision special machining process widely used in the manufacturing of precision molds, aerospace parts, and precision mechanical parts. During wire EDM, the electrode wire acts as the cutting tool, and its tension directly affects the cutting accuracy, surface quality, and machining stability.

[0003] During wire EDM, the electrode wire tension changes due to various factors. When cutting workpieces of different materials or thicknesses, variations in cutting resistance alter the stress state of the electrode wire. Vibrations, temperature changes, and the elastic deformation of the electrode wire itself during processing also cause tension fluctuations. If these tension changes are not controlled in a timely and effective manner, they can lead to unstable discharge gaps, affecting cutting quality and, in severe cases, even causing wire breakage and interrupting the processing.

[0004] In existing wire EDM equipment, tension control mainly employs passive adjustment methods such as gravity balance or spring compensation. Gravity balance tension control provides constant tension by suspending a weight, but this method has a limited adjustment range and cannot be adjusted in real time according to actual processing conditions. Spring compensation tension control relies on the elastic force of a spring to maintain tension, but the spring characteristics change with temperature and usage time, affecting the stability of tension control.

[0005] More importantly, these traditional tension control methods are all passive adjustments. When external factors cause changes in tension, the system cannot actively and quickly compensate for these changes. In precision machining, when the workpiece material hardness changes or the cutting path becomes complex and varied, fluctuations in electrode wire tension can significantly affect machining accuracy and surface quality. Traditional passive adjustment methods have slow response speeds and low adjustment accuracy, making it difficult to meet the stringent requirements of tension stability in modern precision manufacturing. Summary of the Invention

[0006] This invention provides a wire feed control device for slow wire electrical discharge machining, which realizes precise and controllable adjustment of electrode wire tension, thereby improving the stability and accuracy of the cutting process.

[0007] This invention provides a wire feeding control device for slow wire electrical discharge machining (EDM), comprising: a support; a wire guide mechanism disposed on the support for feeding the electrode wire; and a tension adjustment mechanism disposed on the support, the tension adjustment mechanism comprising: multiple smooth guide rollers connected by a tension belt; and a magnetic powder controller, the output end of which is connected to one of the smooth guide rollers; wherein the electrode wire is clamped between the tension belt and one of the smooth guide rollers, and the magnetic powder controller controls the braking torque acting on the smooth guide rollers by adjusting the excitation current, the braking torque acting on the electrode wire through the tension belt to generate controllable tension, for real-time adjustment of the electrode wire tension.

[0008] In one possible implementation, the system further includes: a tension detection mechanism mounted on a support for detecting the real-time tension of the electrode wire; and a control module electrically connected to the tension detection mechanism and the magnetic powder controller, wherein the control module adjusts the excitation current of the magnetic powder controller based on the deviation between the real-time tension detected by the tension detection mechanism and the set tension.

[0009] In one possible implementation, the tension detection mechanism includes: a swing arm, one end of which is rotatably connected to a bracket via a rotating shaft; a detection wheel, rotatably disposed at the free end of the swing arm; a cam, disposed on the rotating shaft; and a displacement sensor for detecting changes in the angle of the cam; wherein an electrode wire is wound around the detection wheel.

[0010] In one possible implementation, the swing angle range of the swing arm is ±15°, the displacement detection accuracy of the displacement sensor is less than or equal to 0.01mm, and the excitation current adjustment range of the magnetic powder controller is 0.5A-5A, so that the tension adjustment response time is less than or equal to 20ms, and the tension fluctuation of the control electrode wire is within ±1N.

[0011] In one possible implementation, the wire guiding mechanism includes: a first motor; a wire feeding drum disposed at the power output end of the first motor; multiple guide wheels rotatably disposed on a bracket; a second motor; and a wire feeding wheel disposed at the power output end of the second motor; wherein, a control module is electrically connected to the first motor and the second motor, and the control module calculates the theoretical tension value of the electrode wire based on the pulse torque signals of the first motor and the second motor.

[0012] In one possible implementation, there are two wire feeding wheels, and a second motor drives the two wire feeding wheels to rotate synchronously in opposite directions through a gear set, with the electrode wire clamped between the two wire feeding wheels.

[0013] In one possible implementation, the outer circumferential surface of the wire feeding wheel is provided with anti-slip grooves, the groove depth of which is 0.1-0.3mm and the groove width is 0.2-0.5mm.

[0014] In one possible implementation, the distance between the two wire feeding rollers is adjustable, with an adjustment range of 0.02-0.35 mm.

[0015] In one possible implementation, the wire guide mechanism further includes a speed detection component connected to the wire feeding wheel for real-time detection of the electrode wire running speed; wherein, the control module is electrically connected to the speed detection component and controls the second motor according to the speed signal from the speed detection component to ensure constant speed feeding of the electrode wire.

[0016] In one possible implementation, the speed detection component is a pulse encoder with a resolution greater than or equal to 1000 lines and a sampling frequency greater than or equal to 100Hz, so that the electrode wire speed control accuracy is within ±0.5%.

[0017] In one possible implementation, the smoothing guide wheel includes a first smoothing wheel and two second smoothing wheels located on both sides of the first smoothing wheel, with the electrode wire sandwiched between the first smoothing wheel and the tension belt.

[0018] In one possible implementation, the tension adjustment mechanism also includes a tensioning pulley for adjusting the tension of the tension belt.

[0019] In one possible implementation, the tension belt is made of polyurethane and is tightly connected to multiple smooth guide pulleys.

[0020] In one possible implementation, the control module employs an adaptive fuzzy PID algorithm.

[0021] In one possible implementation, the control module includes a human-computer interaction unit.

[0022] The wire feed control device for slow-speed wire EDM provided by this invention achieves precise and controllable adjustment of electrode wire tension through the cooperation of a magnetic powder controller, smooth guide wheels, and a tension belt, significantly improving the stability and accuracy of the cutting process. Specifically, the working principle is as follows: the magnetic powder controller controls the braking torque at its output end by adjusting the excitation current. This braking torque acts on the smooth guide wheels connected to it. Since multiple smooth guide wheels are connected via a tension belt, the braking torque can be transmitted to the entire transmission system through the tension belt. When the electrode wire is clamped between the tension belt and the smooth guide wheels, the tension on the tension belt directly acts on the electrode wire, thereby generating controllable electrode wire tension. Compared with traditional gravity counterweight or spring tension systems, this design has significant advantages such as a large adjustment range, fast response speed, and high control accuracy.

[0023] The excitation current of the magnetic powder controller can be continuously adjusted, thus enabling stepless adjustment of the electrode wire tension to adapt to the varying tension requirements of different workpiece materials and cutting processes. During processing, when the workpiece material hardness changes or the cutting conditions change, the system can adjust the braking torque in real time by regulating the excitation current of the magnetic powder controller, thereby adjusting the tension acting on the electrode wire. This ensures that the discharge gap remains stable, avoiding decreased cutting accuracy or wire breakage caused by tension fluctuations. The smooth guide wheel and tension belt transmission connection ensures the smoothness and uniformity of tension transmission, avoiding the impact and vibration that may occur with traditional gear transmissions, and providing a more stable tension environment for the electrode wire. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0025] Figure 1 This is a three-dimensional structural schematic diagram of a wire cutting control device for slow wire EDM provided by the present invention.

[0026] Figure 2 This is a schematic diagram of the planar structure of a slow wire EDM wire cutting control device provided by the present invention.

[0027] Figure 3 This is a three-dimensional structural schematic diagram of a tension detection mechanism provided by the present invention.

[0028] Figure 4 This is a three-dimensional structural schematic diagram of a tension adjustment mechanism provided by the present invention.

[0029] Figure 5 This is a three-dimensional structural diagram of a second motor, gear set, and wire feeding wheel provided by the present invention.

[0030] Figure 6 This is a control block diagram of a slow wire EDM wire cutting control device provided by the present invention.

[0031] Figure label: a. Electrode wire; 1. Bracket; 2. Wire guiding mechanism; 21. First motor; 22. Wire feeding drum; 23. Guide wheel; 24. Second motor; 25. Wire feeding wheel; 26. Gear set; 27. Speed ​​detection assembly; 3. Tension adjustment mechanism; 31. Smoothing guide wheel; 311. First smoothing wheel; 312. Second smoothing wheel; 32. Tension belt; 33. Magnetic powder controller; 4. Tension detection mechanism; 41. Swing arm; 42. Rotating shaft; 43. Detection wheel; 44. Cam; 45. Displacement sensor; 5. Control module. Detailed Implementation

[0032] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this invention. All other embodiments obtained by those skilled in the art based on the embodiments of this invention without creative effort are within the scope of protection of this invention.

[0033] The following is combined with Figures 1 to 6 The present invention describes a wire feeding control device for slow wire electrical discharge machining, comprising a support 1, a wire guide mechanism 2, and a tension adjustment mechanism 3, wherein: The wire guide mechanism 2 is mounted on the support 1 and is used to transport the electrode wire a.

[0034] The tension adjustment mechanism 3 is mounted on the bracket 1. The tension adjustment mechanism 3 includes: a plurality of smooth guide wheels 31, which are connected by a tension belt 32; and a magnetic powder controller 33, the output of which is connected to one of the smooth guide wheels 31.

[0035] The electrode wire a is sandwiched between the tension belt 32 and one of the smoothing guide rollers 31. The magnetic powder controller 33 controls the braking torque acting on the smoothing guide roller 31 by adjusting the excitation current. The braking torque acts on the electrode wire a through the tension belt 32 to generate controllable tension, which is used to adjust the tension of the electrode wire a in real time.

[0036] In this invention, the precise and controllable adjustment of the tension of electrode wire a is achieved through the cooperation of magnetic powder controller 33, smooth guide wheel 31, and tension belt 32, significantly improving the stability and accuracy of the cutting process. Specifically, the magnetic powder controller 33 controls the braking torque at its output end by adjusting the excitation current. This braking torque acts on the smooth guide wheel 31 connected to it. Since multiple smooth guide wheels 31 are connected by a tension belt 32, the braking torque can be transmitted to the entire transmission system through the tension belt 32. When electrode wire a is sandwiched between the tension belt 32 and the smooth guide wheel 31, the tension on the tension belt 32 directly acts on electrode wire a, thereby generating controllable tension in electrode wire a. Compared with traditional gravity counterweight or spring tension systems, this design has significant advantages such as a large adjustment range, fast response speed, and high control accuracy.

[0037] The excitation current of the magnetic powder controller 33 can be continuously adjusted, thus enabling stepless adjustment of the tension of the electrode wire a, adapting to the varying tension requirements of different workpiece materials and cutting processes. During processing, when the hardness of the workpiece material changes or the cutting conditions change, the system can adjust the braking torque in real time by adjusting the excitation current of the magnetic powder controller 33, thereby adjusting the tension acting on the electrode wire a, ensuring that the discharge gap remains stable, and avoiding decreased cutting accuracy or wire breakage due to tension fluctuations. The transmission connection between the smooth guide wheel 31 and the tension belt 32 ensures the smoothness and uniformity of tension transmission, avoiding the impact and vibration that may occur with traditional gear transmission, and providing a more stable tension environment for the electrode wire a.

[0038] The device features a compact structure. The design of multiple smooth guide rollers 31 connected by a tension belt 32 reduces mechanical transmission links, lowers system complexity and failure rate, and improves transmission efficiency. The magnetic powder controller 33, as a mature industrial control component, features fast response, high control precision, and long service life. Its contactless electromagnetic control method avoids mechanical friction loss, improving system reliability and durability. The configuration of the electrode wire a, clamped between the tension belt 32 and the smooth guide rollers 31, makes the tension application point closer to the actual cutting position, reducing losses and delays in the tension transmission process and improving the real-time performance and accuracy of tension control. Especially in high-precision applications such as precision mold processing and complex contour cutting, this precise tension control capability directly translates into higher processing quality and a more stable processing process.

[0039] Specifically, the excitation current of the magnetic powder controller 33 is directly proportional to the braking torque. As the excitation current increases, the braking torque increases, increasing the rotational resistance of the connected smooth guide wheel 31. This resistance change is transmitted to the electrode wire a via the mechanical transmission of the tension belt 32, causing a corresponding increase in tension on the electrode wire a. Multiple smooth guide wheels 31 are connected by the tension belt 32 to form a transmission system, ensuring effective transmission of the braking torque. The positioning of the electrode wire a between the tension belt 32 and the smooth guide wheel 31 utilizes the belt's encircling constraint to make the tension adjustment process smoother and more stable.

[0040] In one specific embodiment, during slow wire EDM machining of precision molds, changes in the workpiece material hardness cause variations in the cutting load, requiring corresponding adjustments to the tension of electrode wire a to maintain a stable discharge gap. The magnetic powder controller 33 adjusts the excitation current according to the control signal, and changes in braking torque are rapidly transmitted to electrode wire a via the tension belt 32, achieving rapid and precise tension adjustment and ensuring the stability and machining accuracy of the cutting process.

[0041] In related technologies, traditional tension control schemes often employ gravity-balanced or spring-compensated mechanical structures. These schemes are passive in their adjustment and cannot respond quickly to real-time tension changes during processing. When the processing load changes, the tension is prone to significant fluctuations, affecting cutting quality and processing accuracy. In this embodiment of the invention, a magnetic powder controller 33 actively adjusts the braking torque, indirectly controlling the tension of the electrode wire a via a tension belt 32. Compared to traditional passive adjustment methods, this offers advantages such as faster response speed and higher control accuracy. The indirect transmission method avoids the impact and damage that might occur if the magnetic powder controller 33 directly acts on the electrode wire a, ensuring smooth tension adjustment and the integrity of the electrode wire a.

[0042] like Figure 6 As shown, in some embodiments, it further includes: a tension detection mechanism 4, disposed on the bracket 1, for detecting the real-time tension of the electrode wire a; and a control module 5, electrically connected to the tension detection mechanism 4 and the magnetic powder controller 33, wherein the control module 5 adjusts the excitation current of the magnetic powder controller 33 according to the deviation between the real-time tension detected by the tension detection mechanism 4 and the set tension.

[0043] In this invention, the tension detection mechanism 4 is mounted on the support 1 to detect the tension change of the electrode wire a in real time. The control module 5 is electrically connected to the tension detection mechanism 4 and the magnetic powder controller 33, forming a closed-loop control system for tension detection-control-execution. The control module 5 continuously monitors the real-time tension signal output by the tension detection mechanism 4, compares it with a preset tension value, calculates the deviation value, and adjusts the excitation current of the magnetic powder controller 33 according to the magnitude and direction of the deviation, thereby achieving automatic tension adjustment.

[0044] Specifically, the tension detection mechanism 4 converts the detected tension change into an electrical signal and transmits it to the control module 5. The control module 5 uses a control algorithm to process the tension deviation information and outputs a corresponding excitation current adjustment command to the magnetic powder controller 33. When the actual tension is lower than the set value, the control module 5 increases the excitation current of the magnetic powder controller 33, increasing the braking torque and thus increasing the tension of the electrode wire a; when the actual tension is higher than the set value, the control module 5 decreases the excitation current, reducing the braking torque and thus decreasing the tension. This negative feedback control mechanism can automatically eliminate tension deviation.

[0045] In one specific embodiment, when cutting a stepped workpiece with varying thickness, the cutting resistance of the electrode wire a differs in different thickness regions, causing tension variations. The tension detection mechanism 4 monitors these variations in real time, and the control module 5 automatically adjusts the excitation current of the magnetic powder controller 33 based on the detection results, ensuring that the tension of the electrode wire a remains within a set range, thus preventing tension fluctuations from affecting cutting quality or causing wire breakage.

[0046] In related technologies, most tension control systems adopt an open-loop control method, adjusting tension only according to preset parameters, and cannot monitor and compensate for the influence of external interference factors in real time. When cutting conditions change, the tension deviates from the set value, and the system cannot correct it automatically, requiring manual intervention. In contrast, the closed-loop control system established in this embodiment of the invention can detect the tension status in real time and adjust it automatically, exhibiting stronger anti-interference capabilities and higher control accuracy compared to open-loop control. The closed-loop control mechanism enables the system to adapt to different processing conditions, reducing the need for manual adjustment and improving the stability and automation level of the processing process.

[0047] like Figure 3 As shown, in some embodiments, the tension detection mechanism 4 includes: a swing arm 41, one end of which is rotatably connected to the bracket 1 via a rotating shaft 42; a detection wheel 43, which is rotatably disposed at the free end of the swing arm 41; a cam 44, which is disposed on the rotating shaft 42; and a displacement sensor 45, which is used to detect the angle change of the cam 44; wherein the electrode wire a is wound around the detection wheel 43.

[0048] In this invention, the tension detection mechanism 4 adopts a mechanical-electronic joint detection scheme consisting of a swing arm 41, a detection wheel 43, a cam 44, and a displacement sensor 45. One end of the swing arm 41 is hinged to the bracket 1 via a rotating shaft 42. The detection wheel 43 is located at the free end of the swing arm 41, and the electrode wire a is wound around the detection wheel 43. When the tension of the electrode wire a changes, the force on the detection wheel 43 changes, causing the swing arm 41 to swing around the rotating shaft 42. The cam 44, fixed on the rotating shaft 42, rotates accordingly. The displacement sensor 45 detects the angle change of the cam 44 and converts the mechanical displacement into an electrical signal output.

[0049] Specifically, minute changes in the tension of electrode wire a are transmitted to the swing arm 41 via the detection wheel 43. The swing angle of the swing arm 41 has a definite geometric relationship with the tension change. The cam 44 mechanism amplifies the angle, converting the minute swing of the swing arm 41 into an angular change of the cam 44, facilitating accurate detection by the displacement sensor 45. The amplitude of the electrical signal output by the displacement sensor 45 is proportional to the angular change of the cam 44, thus establishing a complete detection link from tension change to electrical signal output. The entire detection process features direct mechanical response and precise electronic detection.

[0050] In a specific embodiment, when the diameter of the electrode wire a is 0.25 mm, and the tension changes from the set 5 N to 6 N during the cutting process, the force of the electrode wire a on the detection wheel 43 increases, the swing arm 41 swings upward at a certain angle, the cam 44 rotates synchronously with the rotating shaft 42, the displacement sensor 45 detects the angle change and outputs the corresponding electrical signal, and the control module 5 judges that the tension has increased by 1 N, and adjusts the magnetic powder controller 33 in time to reduce the excitation current to reduce the tension.

[0051] In this embodiment of the invention, an indirect detection method is adopted, so the displacement sensor 45 does not need to be in direct contact with the electrode wire a, avoiding the interference and wear problems that may be caused by contact detection. The swing arm 41 mechanism converts tension changes into angle changes, which facilitates high-precision detection by the displacement sensor 45. The overall detection system has a simple structure, high reliability, and is easy to maintain.

[0052] In some embodiments, the swing angle range of the swing arm 41 is ±15°, the displacement detection accuracy of the displacement sensor 45 is less than or equal to 0.01mm, and the excitation current adjustment range of the magnetic powder controller 33 is 0.5A-5A, so that the tension adjustment response time is less than or equal to 20ms, and the tension fluctuation of the electrode wire a is controlled within ±1N.

[0053] In this invention, by limiting the swing angle range of the swing arm 41 to ±15°, the tension detection system is ensured to have good linearity and sensitivity within its effective working range. The displacement sensor 45, with a displacement detection accuracy of less than or equal to 0.01 mm, guarantees high precision in angle change detection, enabling it to capture minute changes in the tension of the electrode wire a. The magnetic powder controller 33, with an excitation current adjustment range of 0.5A-5A, covers the tension control requirements of electrode wires a of different specifications, achieving a tension adjustment response time of less than or equal to 20 ms and high-precision control of tension fluctuations within ±1 N.

[0054] Specifically, the swing range of the swing arm 41 ± 15° has been verified through kinematic analysis and experiments. Within this angle range, the angular displacement of the swing arm 41 exhibits a good linear relationship with the tension change of the electrode wire a, facilitating the implementation of the control algorithm. The high-precision detection capability of the displacement sensor 45 enables the system to distinguish minute changes in tension, providing a reliable feedback signal for precise control. The wide excitation current adjustment range of the magnetic powder controller 33 adapts to electrode wires a of different diameters and materials, and its fast response time ensures that the system can respond to tension changes in a timely manner.

[0055] In some embodiments, the wire guiding mechanism 2 includes: a first motor 21; a wire feeding drum 22 disposed at the power output end of the first motor 21; a plurality of guide wheels 23 rotatably disposed on the bracket 1; a second motor 24; and a wire feeding wheel 25 disposed at the power output end of the second motor 24; wherein, the control module 5 is electrically connected to the first motor 21 and the second motor 24, and the control module 5 calculates the theoretical tension value of the electrode wire a based on the pulse torque signals of the first motor 21 and the second motor 24.

[0056] like Figure 1 and Figure 2 As shown, in this invention, the wire guiding mechanism 2 includes a complete transmission system comprising a first motor 21, a wire feeding drum 22, multiple guide rollers 23, a second motor 24, and a wire feeding roller 25. The first motor 21 drives the wire feeding drum 22 to wind up the electrode wire a, and the second motor 24 drives the wire feeding roller 25 to feed the electrode wire a. The control module 5 is electrically connected to the first motor 21 and the second motor 24. By collecting the pulse torque signals of the two motors and combining the motor load characteristics and transmission relationship, the theoretical tension value of the electrode wire a is calculated, forming a dual verification mechanism with the direct detection result of the tension detection mechanism 4.

[0057] Specifically, the load torque of the first motor 21 and the second motor 24 during operation is related to the tension of the electrode wire a. When the tension of the electrode wire a increases, the winding resistance of the first motor 21 increases, and the feed resistance of the second motor 24 also changes accordingly. The torque signals of the two motors reflect the stress state of the electrode wire a. The control module 5 can calculate the theoretical tension value by collecting and analyzing the motor torque signals. This value serves as an auxiliary reference for tension detection and is cross-checked with the direct detection results of the displacement sensor 45 of the swing arm 41. The first motor 21 is a permanent magnet synchronous motor with a rated power of 1kW and a rated speed of 3000r / min. It is equipped with an absolute encoder with a resolution of ≥20 bits. Its output shaft is rigidly connected to the wire feed drum 22 through a coupling, driving the wire feed drum 22 to complete the cyclic winding and unwinding of the electrode wire a.

[0058] In one specific embodiment, when the electrode wire a has a diameter of 0.2 mm and the tension is set to 8 N during the cutting process, the displacement sensor 45 detects and displays a tension of 7.8 N. Simultaneously, the control module 5 calculates a theoretical tension of 7.9 N based on the torque signals from the first motor 21 and the second motor 24. The consistency of these two values ​​verifies the accuracy of the tension detection. If the two detected values ​​differ significantly, the system can determine that an abnormality exists and take corresponding measures.

[0059] In this embodiment of the invention, the established dual detection mechanism improves the reliability and accuracy of tension detection. By mutually verifying two detection methods based on different principles, sensor faults or detection anomalies can be effectively identified, improving the system's fault tolerance. The motor torque signal serves as the basis for calculating theoretical tension, providing additional data support for tension control and enhancing the stability of the control system.

[0060] like Figure 5 As shown, in some embodiments, there are two wire feeding wheels 25. The second motor 24 drives the two wire feeding wheels 25 to rotate synchronously in opposite directions through a gear set 26. The electrode wire a is sandwiched between the two wire feeding wheels 25.

[0061] In this invention, the arrangement of two wire feeding wheels 25 changes the traditional single-wheel drive method. The second motor 24 drives the two wire feeding wheels 25 to rotate synchronously in opposite directions through a gear set 26, with the electrode wire a clamped between the two wire feeding wheels 25. The dual-wheel clamping method forms a symmetrical constraint force on the electrode wire a, eliminating the lateral force that may be generated by single-wheel drive. The gear set 26 transmission ensures the strict synchronous operation of the two wire feeding wheels 25, avoiding the stretching or compression deformation of the electrode wire a due to the difference in rotational speed.

[0062] Specifically, the two wire feeding wheels 25 serve as the driving and driven wheels, respectively, and are mechanically connected by a gear set 26 to achieve synchronous and opposite rotation, with a speed ratio of 1:1 but opposite directions. The electrode wire a is clamped between the two wheels and receives a uniform driving force, avoiding the deviation of the electrode wire a that may be caused by unilateral driving. Compared with belt drive, gear transmission has higher transmission accuracy and synchronization, ensuring the consistency of the speed of the two wire feeding wheels 25 and providing stable feed power for the electrode wire a. The second motor 24 is a permanent magnet synchronous motor with a rated power of 1.5kW and a rated speed of 2000r / min. It is equipped with an absolute encoder with a resolution of ≥20 bits. Its output shaft is connected to the two wire feeding wheels 25 through a precision cylindrical gear set 26. The transmission ratio of the driving wheel and the driven wheel is 1:2. The module of the driving wheel and the driven wheel is 0.5, and the number of teeth is 20 and 40, respectively. The distance between the two rollers can be adjusted within the range of 0.02-0.35mm by adjusting the gear meshing clearance.

[0063] In this embodiment of the invention, the synchronous drive of the dual wire feed wheels 25 provides a more stable and uniform feed force, offering better transmission stability and reliability compared to single-wheel drive. Symmetrical clamping eliminates the influence of lateral forces, ensuring the straightness and stability of the electrode wire a during feeding, and providing reliable feed assurance for high-precision cutting.

[0064] In some embodiments, the outer peripheral surface of the wire feeding wheel 25 is provided with anti-slip texture, the groove depth of the anti-slip texture is 0.1-0.3mm and the groove width is 0.2-0.5mm.

[0065] In this invention, the outer circumferential surface of the wire feeding wheel 25 is provided with anti-slip texture. The technical parameters of the groove depth (0.1-0.3 mm) and groove width (0.2-0.5 mm) have been optimized to ensure sufficient friction to prevent the electrode wire a from slipping while avoiding excessive damage to the surface of the electrode wire a. The presence of the anti-slip texture increases the contact area and friction coefficient between the wire feeding wheel 25 and the electrode wire a, thereby improving the reliability of the feed transmission.

[0066] Specifically, the groove depth of the anti-slip texture is set in the range of 0.1-0.3mm, which provides effective mechanical constraint to prevent electrode wire a from slipping, without causing significant deformation or damage to the thin-diameter electrode wire a due to excessive groove depth. The groove width of 0.2-0.5mm ensures sufficient contact width, disperses contact stress, and reduces local pressure on electrode wire a. The geometry and dimensional parameters of the anti-slip texture comprehensively consider the adaptation requirements of electrode wires a of different diameters.

[0067] In this embodiment of the invention, the optimized anti-slip texture parameters provide reliable friction while minimizing damage to the surface of electrode wire a. The reasonable groove depth and width design balances the requirements of transmission reliability and electrode wire a protection, providing technical assurance for the stable feeding of electrode wires a of different specifications.

[0068] In some embodiments, the distance between the two wire feeding rollers 25 is adjustable, with an adjustment range of 0.02-0.35 mm.

[0069] In this invention, the spacing between the two wire feeding rollers 25 is adjustable, with an adjustment range of 0.02-0.35mm, adapting to the clamping requirements of electrode wires a of different diameters. The spacing adjustment function enables the system to provide the most appropriate clamping force for each specification of electrode wire a. Too small a spacing avoids excessive deformation of the electrode wire a, while too large a spacing prevents slippage caused by insufficient clamping force.

[0070] Specifically, the spacing adjustment mechanism is achieved through a precise mechanical structure. The operator can adjust the distance between the two feeding rollers 25 according to the diameter of the electrode wire a, ensuring that the electrode wire a receives appropriate clamping force between the rollers. A minimum spacing of 0.02mm accommodates the clamping requirements of fine-diameter electrode wires a, while a maximum spacing of 0.35mm meets the requirements for thicker-diameter electrode wires a. Precise spacing adjustment ensures optimal clamping performance for electrode wires a of different specifications.

[0071] In one specific embodiment, when changing the electrode wire a from a diameter of 0.1 mm to a diameter of 0.3 mm, the operator adjusts the spacing of the wire feeding rollers 25 from 0.12 mm to 0.32 mm through the adjustment mechanism, so that the new specification electrode wire a obtains appropriate clamping force, which not only ensures the reliability of feeding, but also avoids excessive compression of the electrode wire a, and maintains the geometric accuracy and surface quality of the electrode wire a.

[0072] In this embodiment of the invention, the adjustable spacing design significantly improves the device's adaptability to different specifications of electrode wire a. Operators can make precise adjustments according to the actual specifications of the electrode wire a used, ensuring that each electrode wire a can obtain the best clamping and feeding effect, expanding the application range of the device and improving its flexibility of use.

[0073] like Figure 6 As shown, in some embodiments, the wire guiding mechanism 2 further includes a speed detection component 27, which is connected to the wire feeding wheel 25 and is used to detect the running speed of the electrode wire a in real time; wherein, the control module 5 is electrically connected to the speed detection component 27 and controls the second motor 24 according to the speed signal of the speed detection component 27 so that the electrode wire a is fed at a constant speed.

[0074] In this invention, the wire guiding mechanism 2 is equipped with a speed detection component 27, which is connected to the wire feeding wheel 25 to detect the running speed of the electrode wire a in real time. The control module 5 is electrically connected to the speed detection component 27 and controls the second motor 24 based on the detected speed signal, forming a speed closed-loop control system. The speed closed-loop control enables the electrode wire a to achieve constant speed feeding, eliminating the influence of load changes, mechanical wear, and other factors on speed stability in open-loop control.

[0075] Specifically, the speed detection component 27 is installed on the wire feeding wheel 25, which is in direct contact with the electrode wire a, and can accurately reflect the actual running speed of the electrode wire a. The control module 5 compares the detected actual speed with the set target speed, calculates the speed deviation, and adjusts the rotational speed of the second motor 24 through a control algorithm to make the speed of the electrode wire a tend towards the set value. The closed-loop control mechanism can automatically compensate for the influence of external interference and maintain speed stability.

[0076] In a specific embodiment, when the speed of electrode wire a is set to 8 m / min, the cutting resistance increases due to the change in the density of the workpiece material during the cutting process. When the actual speed of electrode wire a drops to 7.8 m / min, the speed detection component 27 immediately detects this change, and the control module 5 correspondingly increases the rotational speed of the second motor 24, so that the speed of electrode wire a returns to 8 m / min. The entire adjustment process is completed quickly and automatically.

[0077] In this embodiment of the invention, the established speed closed-loop control system can monitor and adjust the speed of electrode wire a in real time, exhibiting higher speed stability and anti-interference capability compared to open-loop control. The constant-speed delivery function ensures the consistency of the discharge gap, improves the cutting surface quality, and reduces processing defects caused by speed fluctuations.

[0078] In some embodiments, the speed detection component 27 is a pulse encoder with a resolution greater than or equal to 1000 lines and a sampling frequency greater than or equal to 100Hz, so that the speed control accuracy of the electrode wire a is within ±0.5%.

[0079] In this invention, the speed detection component 27 is implemented using a pulse encoder. The pulse encoder has a resolution greater than or equal to 1000 lines and a sampling frequency greater than or equal to 100Hz, providing technical assurance for high-precision speed detection. The high-resolution encoder can detect minute angular changes in the wire feeding wheel 25, and the high sampling frequency ensures the real-time performance of speed detection, ultimately achieving a speed control accuracy of electrode wire a within ±0.5%.

[0080] Specifically, the 1000-line resolution pulse encoder generates 1000 pulse signals per revolution of the wire feed roller 25. Combined with the diameter parameter of the wire feed roller 25, the linear velocity of electrode wire a can be accurately calculated. The 100Hz sampling frequency means that the speed data is updated every 10ms, providing timely feedback to the control system. High-precision speed detection lays the foundation for accurate speed control, enabling the system to promptly detect and correct speed deviations.

[0081] In this embodiment of the invention, a high-precision pulse encoder and optimized control algorithm are used to achieve a speed control accuracy of ±0.5%, which is a significant improvement compared to traditional technologies. This high-precision speed control ensures the stability of the cutting process and improves the consistency of processing quality, making it particularly suitable for precision machining applications where high speed stability is required.

[0082] like Figure 4 As shown, in some embodiments, the smoothing guide wheel 31 includes a first smoothing wheel 311 and two second smoothing wheels 312 located on both sides of the first smoothing wheel 311, and the electrode wire a is sandwiched between the first smoothing wheel 311 and the tension belt 32.

[0083] In this invention, the smoothing guide wheel 31 adopts a three-wheel layout design with a first smoothing wheel 311 and two second smoothing wheels 312 located on both sides. The electrode wire a is sandwiched between the first smoothing wheel 311 and the tension belt 32. This layout allows the tension belt 32 to form a stable transmission path on the three guide wheels, increases the belt wrap angle, and improves transmission efficiency and reliability. The middle first smoothing wheel 311 is in direct contact with the electrode wire a, while the second smoothing wheels 312 on both sides play a guiding and supporting role.

[0084] Specifically, the geometric relationship formed by the three-wheel layout allows the tension belt 32 to stably wrap around each guide pulley, avoiding belt slack or over-tension. The first smooth pulley 311 is located in the central position, resulting in more stable contact with the electrode wire a, which is conducive to accurate tension transmission. The symmetrical arrangement of the two second smooth pulleys 312 balances the belt tension, prevents lateral displacement of the belt, and ensures the geometric accuracy and long-term stability of the transmission system.

[0085] In this embodiment of the invention, the three-wheel layout optimizes the transmission path of the tension belt 32, resulting in better transmission stability and higher transmission efficiency compared to a simpler layout. The rational geometric configuration ensures a good fit between the belt and the guide pulleys, extending their service life and providing a reliable mechanical transmission foundation for the tension control system.

[0086] In some embodiments, the tension adjustment mechanism 3 further includes a tension wheel for adjusting the tension of the tension belt 32.

[0087] In this invention, a tension adjustment mechanism 3 is supplemented with a tension wheel, which is used to adjust the tension of the tension belt 32. The tension wheel solves the problem of belt loosening that may occur during long-term use. By adjusting the position of the tension wheel, the elastic deformation and wear elongation of the belt can be compensated, maintaining the optimal working condition of the transmission system.

[0088] Specifically, the tension pulley is typically located on one side of the tension belt 32. The relative position of the tension pulley to the belt path can be changed via a mechanical adjustment mechanism, thereby adjusting the belt tension. When the belt becomes loose due to prolonged use, the tension pulley can be moved to restore proper tension. Proper belt tension ensures effective contact between the belt and the guide pulleys, preventing slippage due to insufficient tension or accelerated wear due to excessive tension.

[0089] In one specific embodiment, after prolonged continuous use, the tension belt 32 exhibits slight elongation. By adjusting the position of the tension pulley, the belt is restored to the appropriate tension, thus restoring the normal operating performance of the transmission system. The adjustment of the tension pulley is simple and convenient, requiring no extended downtime and improving equipment efficiency.

[0090] In this embodiment of the invention, the adjustable design of the tensioner provides a flexible tension control method, offering better adaptability and maintenance convenience compared to fixed tension. The adjustable tension function extends the belt's service life, reduces maintenance costs, and improves the reliability and economy of the transmission system.

[0091] In some embodiments, the tension belt 32 is made of polyurethane and is tightly connected to a plurality of smooth guide pulleys 31.

[0092] In this invention, the tension belt 32 is made of polyurethane, which has excellent elasticity, wear resistance, and chemical stability, and can withstand repeated stretching and bending during tension transmission. The tension belt 32 is tightly connected to multiple smooth guide pulleys 31, ensuring synchronization and precision during transmission and avoiding energy loss and reduced control precision caused by sliding friction.

[0093] Specifically, the elastic properties of polyurethane allow the belt to adapt to the geometry of the guide pulley, achieving a good fit and contact, while also providing a certain degree of cushioning to absorb impacts and vibrations during transmission. The material's wear resistance ensures the belt's dimensional stability and transmission accuracy over long-term use. The tight fit eliminates transmission gaps, improving the timeliness and accuracy of tension transmission.

[0094] In one specific embodiment, the polyurethane tension belt 32 exhibits good durability during continuous use, maintaining a stable contact with the smooth guide pulley 31 without significant wear or deformation. The belt's elastic properties effectively absorb minor vibrations during system operation, maintaining smooth tension transmission and providing a reliable transmission medium for precise tension control.

[0095] In this embodiment of the invention, the selection of polyurethane material fully considers the special requirements of tension transmission, and it has better overall performance compared to traditional materials. The excellent performance of the polyurethane belt ensures the accuracy and stability of tension transmission, provides a reliable material basis for high-precision tension control, and extends the service life of the transmission system.

[0096] In some embodiments, the control module 5 employs an adaptive fuzzy PID algorithm.

[0097] In this invention, control module 5 employs an adaptive fuzzy PID algorithm, which combines the advantages of fuzzy control and PID control, exhibiting stronger adaptability and robustness. The fuzzy control component can handle the nonlinear characteristics and uncertainties in the tension control process, while the adaptive algorithm continuously optimizes the control effect through online learning and parameter adjustment, adapting to different processing conditions and system state changes.

[0098] Specifically, the adaptive fuzzy PID algorithm first processes the input tension deviation signal using fuzzy logic, derives a preliminary control strategy through fuzzy rule inference, and then uses a PID controller for precise adjustment. The adaptive mechanism automatically adjusts the fuzzy rules and PID parameters based on the system's response characteristics, gradually improving the control effect. This intelligent control method reduces the complexity of manual parameter tuning and improves the system's automation level.

[0099] In a preferred embodiment of the present invention, the control module 5 uses a high-performance 32-bit ARM processor as the core control unit, with a main frequency of over 1 GHz, ensuring the system's fast response capability. The control module 5 is equipped with at least 128 MB of RAM for program execution and data caching, and at least 512 MB of Flash storage space for storing control programs, parameter configurations, and historical data.

[0100] The control module 5 establishes electrical connections with various system components through multiple interface circuits, including a digital signal interface with the pulse encoder, an analog signal interface with the displacement sensor 45, a drive control interface with the first motor 21 and the second motor 24, and a current control interface with the magnetic powder controller 33. These interface circuits employ opto-isolation and signal conditioning technologies to ensure the accuracy of signal transmission and the system's anti-interference capability.

[0101] Control module 5 employs an adaptive fuzzy PID algorithm to achieve intelligent control of the wire feeding system. This algorithm first collects key system state parameters in real time using various sensors, including wire speed deviation, tension deviation, and 41° angular displacement of the swing arm. The algorithm then divides the deviations and rates of change of these input quantities into seven fuzzy subsets: negative large, negative medium, negative small, zero, positive small, positive medium, and positive large, establishing a complete fuzzy input space.

[0102] The system's built-in fuzzy rule table contains more than 50 control rules, covering control strategies under various operating conditions. The fuzzy inference engine performs inference calculations based on the current input state using the fuzzy rule table to derive a preliminary control quantity. This preliminary control quantity is then used as the basis for adjusting the parameters of the PID controller, dynamically adjusting the proportional coefficient Kp, integral coefficient Ki, and derivative coefficient Kd of the PID controller to achieve adaptive optimization of the control parameters.

[0103] After processing by the fuzzy PID algorithm, the control module 5 finally outputs three types of precise control signals: the first type is the PWM drive signal output to the first motor 21, the duty cycle of which can be continuously adjusted within the range of 0-100%, used to precisely control the speed and torque output of the first motor; the second type is the speed adjustment amount output to the second motor 24, with an adjustment range of -50r / min to +50r / min, to achieve fine adjustment of the speed of the second motor 24; the third type is the excitation current adjustment amount output to the magnetic powder controller 33, with an adjustment range of -0.5A to +0.5A, used to precisely control the braking torque generated by the magnetic powder controller 33.

[0104] Through the synergistic effect of these three types of control signals, the system achieves closed-loop coordinated control of electrode wire tension, wire feed speed, and swing arm position, ensuring the stability and accuracy of various parameters during slow wire cutting. The application of the adaptive fuzzy PID algorithm gives the system good self-learning and self-adjustment capabilities, enabling it to adapt to different processing conditions and workpiece materials, thus improving the intelligence level of the control system and the consistency of processing quality.

[0105] In this embodiment of the invention, the adaptive fuzzy PID algorithm has a higher degree of intelligence and adaptability compared to traditional control methods. It can automatically handle various complex control situations and reduce the technical requirements for operators. The intelligent control algorithm improves the accuracy and stability of tension control, providing advanced control technology support for achieving high-quality wire EDM cutting.

[0106] In some embodiments, the control module 5 includes a human-computer interaction unit.

[0107] In this invention, the control module 5 includes a human-machine interface unit, which provides operators with an intuitive monitoring and operation interface. The human-machine interface unit allows operators to view the real-time operating status of the tension control system, including key parameters such as set tension, actual tension, and tension deviation. Simultaneously, it allows for convenient adjustment of control parameters and set values ​​to adapt to different processing requirements.

[0108] Specifically, the human-machine interface (HMI) unit typically includes hardware devices such as a display screen, operation buttons, or a touch interface, as well as corresponding software programs. The display interface can show the system's real-time operating data in graphical or numerical form, while the operation interface allows users to input new setpoints or modify control parameters. HMI functions also include fault diagnosis and alarm prompts, enabling timely notification of operators and provision of fault information when system anomalies occur.

[0109] In one specific embodiment, the operator can observe the real-time changes of the tension control curve through the human-machine interface unit. When large tension fluctuations are detected, relevant parameters can be adjusted promptly or the system status can be checked. Alarm information on the interface helps the operator quickly locate problems, shortens troubleshooting time, and improves the operating efficiency and reliability of the equipment.

[0110] The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this embodiment according to actual needs. Those skilled in the art can understand and implement this without any creative effort.

[0111] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A wire feed control device for slow wire electrical discharge machining, characterized in that, include: Support (1); The wire guide mechanism (2) is mounted on the bracket (1) and is used to transport the electrode wire; A tension adjustment mechanism (3) is disposed on the bracket (1), and the tension adjustment mechanism (3) includes: Multiple smooth guide wheels (31) are connected by a tension belt (32); A magnetic powder controller (33) is provided, the output of which is connected to one of the smooth guide wheels (31). The electrode wire is sandwiched between the tension belt (32) and one of the smooth guide rollers (31). The magnetic powder controller (33) controls the braking torque acting on the smooth guide roller (31) by adjusting the excitation current. The braking torque acts on the electrode wire through the tension belt (32) to generate controllable tension, which is used to adjust the tension of the electrode wire in real time.

2. The wire feed control device for slow wire EDM according to claim 1, characterized in that, Also includes: Tension detection mechanism (4) is set on the bracket (1) and is used to detect the real-time tension of the electrode wire; The control module (5) is electrically connected to the tension detection mechanism (4) and the magnetic powder controller (33). The control module (5) adjusts the excitation current of the magnetic powder controller (33) according to the deviation between the real-time tension detected by the tension detection mechanism (4) and the set tension.

3. The wire feed control device for slow wire EDM according to claim 2, characterized in that, The tension detection mechanism (4) includes: A swing arm (41), one end of which is rotatably connected to the bracket (1) via a pivot (42); The detection wheel (43) is rotatably mounted on the free end of the swing arm (41); A cam (44) is mounted on the rotating shaft (42); Displacement sensor (45) is used to detect the angle change of the cam (44); The electrode wire is wound around the detection wheel (43).

4. The wire feed control device for slow wire EDM according to claim 3, characterized in that, The swing angle range of the swing arm (41) is ±15°, and the displacement detection accuracy of the displacement sensor (45) is less than or equal to 0.01mm; The excitation current adjustment range of the magnetic powder controller (33) is 0.5A-5A, so that the tension adjustment response time is less than or equal to 20ms, and the tension fluctuation of the electrode wire is controlled within ±1N.

5. The wire feed control device for slow wire EDM according to claim 2, characterized in that, The guide wire mechanism (2) includes: First motor (21); The wire feed drum (22) is located at the power output end of the first motor (21); Multiple guide wheels (23) are rotatably mounted on the bracket (1); Second motor (24); The wire feeding wheel (25) is located at the power output end of the second motor (24); The control module (5) is electrically connected to the first motor (21) and the second motor (24). The control module (5) calculates the theoretical tension value of the electrode wire based on the pulse torque signals of the first motor (21) and the second motor (24).

6. The wire feed control device for slow wire EDM according to claim 5, characterized in that, There are two wire feeding wheels (25). The second motor (24) drives the two wire feeding wheels (25) to rotate synchronously in opposite directions through a gear set (26). The electrode wire is clamped between the two wire feeding wheels (25).

7. The wire feed control device for slow wire EDM according to claim 5, characterized in that, The wire guiding mechanism (2) further includes a speed detection component (27), which is connected to the wire feeding wheel (25) and is used to detect the running speed of the electrode wire in real time. The control module (5) is electrically connected to the speed detection component (27) and controls the second motor (24) according to the speed signal of the speed detection component (27) so that the electrode wire is conveyed at a constant speed.

8. The wire feed control device for slow wire EDM according to any one of claims 1-7, characterized in that, The smoothing guide wheel (31) includes a first smoothing wheel (311) and two second smoothing wheels (312) located on both sides of the first smoothing wheel (311). The electrode wire is sandwiched between the first smoothing wheel (311) and the tension belt (32).

9. The wire feed control device for slow wire EDM according to any one of claims 1-7, characterized in that, The tension adjustment mechanism (3) further includes a tension wheel, which is used to adjust the tension of the tension belt (32).

10. The wire feed control device for slow wire EDM according to any one of claims 2-7, characterized in that, The control module (5) adopts an adaptive fuzzy PID algorithm.

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