Electric cutting device and method for machining mold accessories

Abstract

The invention discloses an electric cutting device and method for machining mold accessories, and relates to the technical field of mold electric cutting. On the basis of a conventional electric cutting equipment structure, a full-bridge tension sensor is installed between a wire collecting workbench and a guide wheel set in combination with two key values of tension fluctuation and current fluctuation; the current detection module is connected with the discharge system in series to obtain a real-time current value, the tension and current reference intervals under different working conditions are pre-stored by additionally arranging the coupling control module in the working period, and the tension and current reference intervals under different working conditions are calculated through actions such as reference parameter calibration, two-parameter real-time acquisition, coupling state two-way judgment and closed-loop coupling optimization. A dynamic incidence relation between tension and discharge current is established, a grading adjustment and compensation mode is adopted according to deviation grades, the limitation of single parameter adjustment is broken, two-way cooperative regulation is achieved, the machining quality is ensured on the premise that the wire breakage risk of the electrode wire is reduced, and the machining preparation period is shortened.

Description

Technical Field

[0001] This invention relates to the field of electric cutting technology for molds, and more specifically to an electric cutting device and method for processing mold parts. Background Technology

[0002] The fundamental difference between wire electrical discharge cutting (hereinafter referred to as EDM) and conventional mechanical stress cutting is that the electrode wire does not contact the product, thus avoiding mechanical stress. The key lies in the discharge system and the wire feeding system. High temperatures are generated through pulsed discharge between the electrode wire and the mold parts to be processed, melting and eroding the metal material to achieve precise material removal.

[0003] Theoretically speaking: cutting quality is not affected by the product material (the only requirement is that the material is conductive), the key lies in the movement and discharge process of the electrode wire: 1. The electrode wire can be used in two forms: high-speed reciprocating motion and unidirectional low-speed motion. The former is low in cost (the electrode wire can be reused) but lacks precision, while the latter is a disposable consumable, which can avoid wear and tear and improve precision. 2. The instantaneous high temperature generated during the discharge process is related to the current. If the energy is insufficient, the processing will stop or the surface will be rough and of poor quality. When processing ultra-thin parts, excessive energy can easily lead to excessive material removal or deformation. Furthermore, the relationship between discharge energy and temperature will also affect the wire feeding process. Without considering the quality of the wire, if the tension of the electrode wire is insufficient, the wire will vibrate more, the discharge will be unstable, and local breakage will occur. Alternatively, if the discharge energy per unit time is too large, the local temperature will be too high and the wire will break. Or, if the discharge energy is insufficient, the cutting difficulty will be increased, and the wire loss will be increased, which will also increase the risk of wire breakage.

[0004] To address the above two issues, this invention proposes a solution. Summary of the Invention

[0005] The purpose of this invention is to provide an electrical cutting device and method for processing mold parts. Without considering the quality of the electrode wire in the wire electrical discharge cutting process, the product cutting quality is directly related to the electrode wire running process and the discharge process. Moreover, the electrode wire running process and the discharge process are interconnected and affect each other, such as the risk of poor product cutting surface quality and electrode wire breakage.

[0006] The objective of this invention can be achieved through the following technical solution: an electric cutting method for processing mold parts, applied in an electric cutting device, wherein a current detection module is added in series with the discharge system in the electric cutting device and the real-time current value in the discharge circuit is acquired in real time; and a coupling control module is set up during the electric cutting operation, consisting of a reference parameter calibration action, a dual parameter acquisition action, a coupling state collaborative judgment action, and a closed-loop coupling optimization action. The coupling control module includes a coupling analysis unit for relating tension and current and a deviation compensation module. The coupling analysis unit is used to establish the dynamic correlation between tension and discharge current, and the deviation compensation module generates compensation commands based on the tension fluctuation characteristics and the current adaptation deviation.

[0007] Further configuration: Add a parameter pre-storage action to the coupling control module, and pre-store the tension reference range and discharge current reference range corresponding to different electrode wire models and workpiece materials in the parameter pre-storage action.

[0008] Further settings include: in the benchmark parameter calibration action, based on the material and thickness of the mold parts to be processed, combined with the attribute parameters of the electrode wire, retrieving the corresponding tension benchmark range and discharge current benchmark range from the parameter storage action, and setting the tension fluctuation judgment standard and current deviation judgment standard. In the dual-parameter real-time acquisition process: after the electric cutting device is started, the tension data of the electrode wire is continuously acquired, and the current detection module synchronously acquires the real-time current value of the discharge circuit and sends it to the coupling state coordination judgment action. In the bidirectional determination of coupling state: the tension data and real-time current value are coupled and bidirectional correlation is determined.

[0009] Further settings include the following determination methods in the bidirectional determination action of the coupled state: Method 1: Analyze the deviation of tension data from the tension reference range, and determine the tension deviation level based on the tension fluctuation state; Method 2: Based on the theoretical matching current corresponding to the current tension data, analyze the deviation between the real-time current value and the theoretical matching current to determine the current matching level; Method 3: Obtain the coupling state of tension and current based on the tension deviation level and current adaptation level.

[0010] Further settings include: In the closed-loop coupling optimization process, current dynamic adjustment is performed first, and includes the following actions: Action 1: When the tension is within the reference range and the current deviation meets the judgment criteria, maintain the current discharge current and continuously monitor parameter fluctuations; Action 2: When the tension is slightly deviated and the fluctuation is relatively smooth, adjust the discharge current according to the coupling state; Action 3: When the tension is in a state of moderate deviation or rapid fluctuation, the deviation compensation module is activated to generate a compensation command and generate a compensation current. Action 4: When the tension is severely deviated, immediately reduce the discharge current to a safe level and trigger the tension correction mechanism of the wire feeding system. After the tension is restored, restore the discharge current according to the coupling state.

[0011] Further settings include: after completing the dynamic current adjustment action, continuously collecting tension and discharge current data, and performing a two-way judgment action on the batch status again. When there is a difference between the tension and the current adaptation level, the coupling status is recalibrated until the tension and discharge current maintain a dynamic adaptation state.

[0012] The system is further configured such that when the discharge current continuously exceeds the current reference range and the duration of the excess reaches a preset threshold, the coupling control module determines that the discharge system is abnormal, immediately cuts off the discharge circuit, and issues an alarm signal.

[0013] The present invention also proposes an electric cutting device for processing mold parts, including a body, a working pool, a wire feeding drum, a wire take-up worktable, a wire wheel, a guide wheel assembly, a full-bridge tension sensor, and a current detection module. The wire feeding circuit is formed by the combination of the wire wheel, the guide wheel assembly, the wire feeding drum, and the wire take-up worktable. The full-bridge tension sensor is installed between the wire take-up worktable and the guide wheel assembly and is used to collect real-time tension data of the electrode wire.

[0014] The present invention has the following beneficial effects: 1. Improvements are made to the wire cutting principle in electrical discharge machining (EDM). By establishing a dynamic correlation between electrode wire tension and discharge current, the limitations of conventional "single parameter adjustment" are eliminated, and bidirectional synergistic control of the two is achieved. For different working conditions such as no tension deviation and slight / moderate / severe tension deviation, graded adjustment and compensation strategies are adopted to effectively solve problems such as unstable discharge gap caused by tension fluctuations, rough cutting surface caused by abnormal current, or excessive material removal.

[0015] 2. In addition to the above, the following measures are taken: On the one hand, the full-bridge tension sensor captures tension fluctuations in real time, and the current detection module monitors the discharge current synchronously. Combined with the graded optimization mechanism, the current is quickly reduced to a safe level and tension correction is triggered when the tension deviates significantly. When the current is abnormal, the circuit is cut off in time and an alarm is triggered, reducing the electrode wire breakage rate and reducing material consumption and rework costs. On the other hand, the closed-loop coupling optimization action realizes dynamic parameter calibration, adapting to the processing needs of mold parts of different thicknesses and materials, and improving the versatility and production efficiency of the equipment. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present 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 only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of the structure of an electric cutting device for processing mold parts proposed in this invention; Figure 2 This is a schematic diagram of the structure of the take-up worktable proposed in this invention; Figure 3 This is a schematic diagram of the electrode wire feeding method proposed in this invention; Figure 4 In this invention Figure 3 The front view; Figure 5 This is a schematic diagram illustrating the operation of an electric cutting method for processing mold parts proposed in this invention.

[0018] In the diagram: 1. Machine body; 2. Working pool; 3. Wire feed drum; 301. Full-bridge tension sensor; 4. Wire take-up table; 5. Wire reel; 6. Guide wheel assembly. Detailed Implementation

[0019] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Example 1: Without considering the quality of the electrode wire in the wire electrical discharge machining (EDM) process, the product cutting quality is directly related to the electrode wire movement and discharge processes, and these processes are interrelated. This can lead to issues such as poor product cut surface quality and the risk of electrode wire breakage. The following technical solution is proposed to address this: Reference Figures 1-4 This embodiment of an electric cutting device for processing mold parts includes a body 1, a working pool 2, a wire feeding drum 3, a wire take-up worktable 4, a wire reel 5, a guide wheel assembly 6, a full-bridge tension sensor 301, and a current detection module. The wire feeding circuit is formed by the wire reel 5, the guide wheel assembly 6, the wire feeding drum 3, and the wire take-up worktable 4. The full-bridge tension sensor 301 is installed between the wire take-up worktable 4 and the guide wheel assembly 6 and is used to collect real-time tension data of the electrode wire.

[0021] Basic Structure and Working Process Description: This section describes the electrical discharge cutting (EDC) technology: its structure is somewhat similar to that of a conventional wire saw, such as... Figure 3 and Figure 4 As shown, multiple guide wheel groups 6 work together with wire wheels to continuously feed wire. The wire moves in a direction and slowly comes into contact with the product. However, the difference in electric cutting technology is that the wire used is an electrode wire rather than the diamond wire used in wire saws. During the continuous cutting process, the electrode wire will not have obvious contact with the product, so no mechanical stress will be generated. The key is that the high temperature generated by the instantaneous discharge of the electrode wire "melts" the cutting metal. The working pool 2 of the present invention is mainly used to hold liquid media such as coolant or cutting fluid, while the overall wire winding worktable 4 is used to facilitate wire winding and ensure that the electrode wire is in a relatively taut state. On the other hand, it is also part of the circuit, and the product on it is used as a motor to complete the closed-loop current flow. Without considering the wire and product materials, the key parameters in the overall cutting process are the discharge current energy and the tension of the electrode wire. When the electrode wire tension is relatively stable, insufficient or excessive current energy will affect the quality of the cut surface. Conversely, when the current energy is relatively stable, excessive tension of the electrode wire may lead to wire breakage. Conversely, if the electrode wire tension is low and fluctuates significantly, the surface roughness of the cut surface will be insufficient. The key content of this invention is to improve the overall electric cutting process by addressing the tension and current values. During operation, the product to be cut is fixed on the wire take-up table 4, and the wire take-up table 4 is directionally moved according to a preset program, while the electrode wire remains energized and directionally moved. The basic electric cutting process does not need to be changed during the overall process.

[0022] Example 2: The overall control process is explained as follows, based on the action process of Example 1: Reference Figure 5 Before a complete set of electrical cutting equipment is put into production, a wire feeding program is preset according to the production parameters, including the physical characteristics of the wire, the discharge parameters and motion parameters of the electrode wire, and the product movement path. Theoretically, the cutting action of the corresponding product can be completed according to this program. However, during actual operation, unexpected situations may occur due to a variety of uncontrollable factors, such as differences in hardness in local areas of the product and fluctuations in the movement state of the electrode wire. The fundamental technical content of this embodiment lies in: first, establishing a benchmark correlation; then, capturing deviations in real time; and finally, performing graded optimization and compensation. The tension state of the electrode wire directly affects its vibration level and stability, while the magnitude of the discharge current determines the processing energy intensity. These two factors do not act independently. Tension fluctuations can lead to instability in the discharge gap, while abnormal current energy can exacerbate electrode wire wear or deformation, thereby causing sudden tension changes. Therefore, this invention breaks through the limitations of "single parameter adjustment" by establishing a dynamic correlation between the two factors, achieving "two-way synergistic control," which ensures processing quality while reducing the risk of wire breakage. The following analysis process is conducted: S1: First, based on past production parameters, record the tension range and discharge current range that can ensure cutting quality and avoid wire breakage under each working condition. Pre-store these data in the module's database to form a standardized benchmark parameter library, providing a "dedicated reference standard" for subsequent processing. This avoids repeated trial and error before processing, shortens preparation time, and ensures that the control direction matches the actual working condition. This part can be directly retrieved from the database of each electric cutting machine, or the corresponding parameters can be edited by professional technicians. S2: Before starting the work, the key information of the current processing task is read first: electrode wire type, workpiece material, and workpiece thickness. This part is only related to the product and is used as a relative fixed value parameter in this invention. Then, the corresponding tension reference range (such as [Tmin, Tmax]) and discharge current reference range (such as [min, Imax]) are retrieved from the pre-stored memory through working condition matching. Based on the retrieved reference range, a reasonable deviation judgment standard is set to determine the maximum allowable tension fluctuation range and the maximum current deviation range, and the judgment method of "normal state" and "abnormal state" is clarified. S3: During the electric cutting process, the real-time tension of the electrode wire is continuously monitored by a full-bridge tension sensor installed between the wire take-up table 4 and the guide wheel group 6, accurately capturing instantaneous tension fluctuations (such as tension jitter caused by uneven discharge, tension attenuation caused by electrode wire wear, and tension sudden changes caused by fluctuations in the wire feeding system). The only difference between the wire take-up table 4 and conventional machining fixtures is that the wire feeding process of the guide wheel group 6 is mainly determined by the setting position of multiple guide wheels, and the key is to ensure that one end of the electrode wire is in a relatively vertical state. Secondly, there is the current detection process. Through the current detection module connected in series with the discharge system, the real-time current value of the discharge circuit is collected synchronously, and the changes in discharge energy (such as the sudden drop in current caused by poor circuit contact, the current overload caused by parameter drift, etc.) are recorded. The two sets of collected data are transmitted to the coupling state judgment unit in real time to ensure data synchronization and avoid misjudgment caused by data delay. S4: This part can be understood as proceeding synchronously with S3. Specifically, it is a bidirectional judgment action of the coupled state. It compares the real-time tension data with the calibrated tension reference range, and combines the frequency and amplitude of tension fluctuations to determine whether the tension is in a state of no deviation, slight deviation, moderate deviation, or severe deviation. For example: if the real-time tension is within the reference range and the fluctuation is gentle, it is judged as no deviation; if the real-time tension exceeds the reference range but the fluctuation is small, it is judged as slight deviation; if the real-time tension significantly exceeds the reference range and the fluctuation is violent, it is judged as severe deviation. Based on the "tension-current correlation" (i.e., the optimal discharge current corresponding to a certain tension state) established by the coupling analysis unit, the theoretical matching current corresponding to the current real-time tension is first determined. Then, the real-time current value is compared with the theoretical matching current to determine whether the current is in a matching, slightly deviated, moderately deviated, or severely deviated state. For example: if the deviation between the real-time current and the theoretical matching current is small, it is determined to be a matching; if the deviation is large and the duration is short, it is determined to be a slightly deviated; if the deviation is significant and continuous, it is determined to be a severely deviated. Secondly, the tension deviation level and the current adaptation level are combined to form the final coupling state (such as "slight tension deviation + slight current deviation", "severe tension deviation + moderate current deviation", etc.) to determine the degree of abnormality of the working condition and the cause of its generation (whether it is the current adaptation deviation caused by the tension problem or the tension change caused by the current abnormality). S5: Combining the above S1~S4 sections, the key content of this invention lies in the closed-loop coupling optimization action. Based on the coupling state determination result, a graded optimization method of "mild adjustment, moderate compensation, and severe emergency response" is adopted: 1) No imbalance state (tension in the reference range + current adaptation): The real-time tension is within the calibrated tension reference range, and the fluctuation amplitude does not exceed the allowable range. The deviation between the real-time current and the theoretical adaptation current is within the allowable range. Optimization method: Maintain the current discharge current and wire feeding system parameters unchanged, and continuously monitor the fluctuations in tension and current to maintain stable operation; 2) Slight imbalance (such as slight deviation of tension, slight deviation of current, or both): There is a slight deviation in tension or current, but the fluctuation is gentle and does not have a significant impact on processing; Optimization method: Make small-scale adjustments based on the coupling state. For example, if the tension is slightly higher than the reference range, appropriately reduce the discharge current to reduce the expansion and deformation of the electrode wire caused by high temperature, thereby alleviating the problem of excessive tension. Conversely, if the current intensity deviates, fine-tune the current according to the tension state so that the two return to the matching state. 3) Moderate imbalance (such as moderate deviation of tension, moderate deviation of current, or rapid fluctuation): The tension or current deviates significantly from the reference range, or the fluctuation frequency is relatively fast; Optimization method: Activate the deviation compensation module to generate targeted compensation instructions. For example, when the tension fluctuates rapidly due to uneven discharge, the discharge energy is adjusted by the compensation current to stabilize the discharge gap and thus suppress tension fluctuations. When the current has a moderate deviation, the current is quickly corrected by the compensation instruction to re-adapt the current to the current tension and prevent the deviation from expanding. 4) Severe imbalance (such as severe tension deviation, severe current deviation): When the tension is significantly beyond the reference range (such as excessive tension or slack), or the current is severely overloaded / insufficient, there is a clear risk of wire breakage or a serious decline in processing quality. Optimization method: Activate the emergency control mechanism to immediately reduce the discharge current to a safe level (to avoid the electrode wire breaking due to high temperature or excessive force), and at the same time trigger the tension correction mechanism of the wire feeding system (such as adjusting the speed of the wire feeding drum, tightening or loosening the electrode wire). After the tension is restored to the reference range, the discharge current is gradually restored according to the new coupling state to ensure that it re-enters a stable state.

[0023] After completing steps 1) to 4) above, proceed to the secondary calibration and abnormal alarm actions: Secondary calibration process: After the above adjustment is completed, the module continuously collects new tension and current data and repeats the coupling state determination process. If the new state has returned to normal, the current parameters are maintained; if there is still a deviation, the optimization action is repeated until the tension and current maintain a dynamic adaptation state.

[0024] Abnormal alarm: If the discharge current is detected to continuously exceed the reference range and reach the preset threshold, the above-mentioned coupling state collaborative judgment method is not required. It is directly judged as an abnormality of the discharge system (such as electrode wire damage, circuit short circuit, etc.), the discharge circuit is immediately cut off and an audible and visual alarm is issued to prompt the operator to check the fault and avoid equipment damage or processing accidents.

[0025] The preferred embodiments of the present invention disclosed above are merely illustrative of the invention. These preferred embodiments do not exhaustively describe all details, nor do they limit the invention to specific implementations. Clearly, many modifications and variations can be made based on the content of this specification. This specification selects and specifically describes these embodiments to better explain the principles and practical applications of the invention, thereby enabling those skilled in the art to better understand and utilize the invention. The invention is limited only by the claims and their full scope and equivalents.

Claims

1. An electric cutting method for processing mold parts, applied in an electric cutting device, characterized in that, A current detection module is added that is connected in series with the discharge system in the electric cutting device and acquires the real-time current value in the discharge circuit. During the electric cutting operation, a coupling control module is set up, which consists of a reference parameter calibration action, a dual parameter acquisition action, a coupling state collaborative judgment action, and a closed-loop coupling optimization action. The coupling control module includes a coupling analysis unit for relating tension and current and a deviation compensation module. The coupling analysis unit is used to establish the dynamic correlation between tension and discharge current, and the deviation compensation module generates compensation commands based on the tension fluctuation characteristics and the current adaptation deviation.

2. The electric cutting method for processing mold parts according to claim 1, characterized in that, A parameter pre-storage action is added to the coupling control module. In the parameter pre-storage action, the tension reference range and discharge current reference range corresponding to different electrode wire models and workpiece materials are pre-stored.

3. The electric cutting method for processing mold parts according to claim 2, characterized in that, In the benchmark parameter calibration action, based on the material and thickness of the mold parts to be processed, combined with the attribute parameters of the electrode wire, the corresponding tension benchmark range and discharge current benchmark range are retrieved from the parameter storage action, and the tension fluctuation judgment standard and current deviation judgment standard are set. In the dual-parameter real-time acquisition process: after the electric cutting device is started, the tension data of the electrode wire is continuously acquired, and the current detection module synchronously acquires the real-time current value of the discharge circuit and sends it to the coupling state coordination judgment action. In the bidirectional determination of coupling state: the tension data and real-time current value are coupled and bidirectional correlation is determined.

4. The electric cutting method for processing mold parts according to claim 3, characterized in that, The bidirectional determination of coupling state includes the following determination methods: Method 1: Analyze the deviation of tension data from the tension reference range, and determine the tension deviation level based on the tension fluctuation state; Method 2: Based on the theoretical matching current corresponding to the current tension data, analyze the deviation between the real-time current value and the theoretical matching current to determine the current matching level; Method 3: Obtain the coupling state of tension and current based on the tension deviation level and current adaptation level.

5. The electric cutting method for processing mold parts according to claim 4, characterized in that, The closed-loop coupling optimization process first performs dynamic current adjustment, which includes the following actions: Action 1: When the tension is within the reference range and the current deviation meets the judgment criteria, maintain the current discharge current and continuously monitor parameter fluctuations; Action 2: When the tension is slightly deviated and the fluctuation is relatively smooth, adjust the discharge current according to the coupling state; Action 3: When the tension is in a state of moderate deviation or rapid fluctuation, the deviation compensation module is activated to generate a compensation command and generate a compensation current. Action 4: When the tension is severely deviated, immediately reduce the discharge current to a safe level and trigger the tension correction mechanism of the wire feeding system. After the tension is restored, restore the discharge current according to the coupling state.

6. The electric cutting method for processing mold parts according to claim 5, characterized in that, After completing the dynamic current adjustment action, the tension and discharge current data are continuously collected, and the bidirectional judgment action of the batch status is performed again. When the tension deviates from the level or the current adaptation level is different, the coupling status is recalibrated until the tension and discharge current maintain a dynamic adaptation state.

7. The electric cutting method for processing mold parts according to claim 6, characterized in that, When the discharge current is detected to continuously exceed the current reference range and the duration exceeds the preset threshold, the coupling control module determines that the discharge system is abnormal, immediately cuts off the discharge circuit and issues an alarm signal.

8. An electric cutting apparatus for processing mold parts, using the electric cutting method for processing mold parts as described in claim 6, characterized in that, The device includes a body (1), a working pool (2), a wire feeding drum (3), a take-up worktable (4), a wire reel (5), a guide wheel assembly (6), a full-bridge tension sensor (301), and a current detection module. The wire feeding circuit is formed by the combination of the wire reel (5), the guide wheel assembly (6), the wire feeding drum (3), and the take-up worktable (4). The full-bridge tension sensor (301) is installed between the take-up worktable (4) and the guide wheel assembly (6) and is used to collect real-time tension data of the electrode wire.

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