A circumferential line cutting device

Abstract

The utility model discloses a circumference line cutting device, the quick wire feeding mechanism is located right rear side of base, the slow wire feeding mechanism is located left rear side of base, the crossbeam connects the inside of quick wire feeding mechanism and slow wire feeding mechanism, and the inside of longitudinal beam connects the inside of crossbeam, and the longitudinal feeding mechanism sleeve joint is longitudinal beam, and the upper side of longitudinal feeding mechanism sleeve joint is the lower side of transverse feeding mechanism, and the rotary feeding mechanism is placed in the upper side of transverse feeding mechanism, and the work piece is located at the rotary feeding mechanism four jaw chuck, and the bracing piece connects the outside of longitudinal beam and the bottom of working fluid recovery pool, and the working fluid recovery pool is located base front end, and the quick wire feeding mechanism, slow wire feeding mechanism, work piece, rotary feeding mechanism connect pulse power supply, and transverse feeding mechanism, longitudinal feeding mechanism, rotary feeding mechanism connect numerical control device, the utility model discloses on the cutting equipment of line has increased rotary feeding mechanism, can process any taper and have spherical arc surface circumference class male die, the utility model discloses similar turning, and the machining precision is higher, and is more suitable for batch processing.

Description

Technical Field

[0001] This utility model belongs to the field of special processing technology, specifically relating to a circumferential wire cutting device. Background Technology

[0002] Commonly used materials for stamping dies include carbon tool steel, low alloy tool steel, high carbon high chromium steel, high speed steel, and cemented carbide. These materials are the mainstream choice for manufacturing die working parts due to their high hardness, high strength, and high wear resistance.

[0003] The high hardness, high strength, and high wear resistance of the above materials limit their machinability. While mold steels such as carbon tool steel, low-alloy tool steel, high-carbon high-chromium steel, and high-speed steel can be annealed and rough-machined, then hardened by heat treatment, and subsequently semi-finished and finished using electrical discharge machining (EDM), the high technical requirements for heat treatment hardening of mold steel often necessitate multiple heat treatments to obtain the desired metallographic structure, resulting in significant heat treatment deformation and thus larger machining allowances. If a forming electrode matching the punch is used for EDM, the ablation of the forming electrode is substantial, and the ablation is uneven across different parts of the forming electrode, requiring timely regrinding by a fitter, which is costly. This is especially true for cemented carbide, which has high hardness, ultra-wear resistance, and high brittleness, making it difficult to machine directly using the forming electrode. Electrical discharge machining (EDM) causes greater erosion of the forming electrode, requiring more frequent manual re-grinding and increasing costs, making mass production difficult. While existing wire EDM equipment can cut and process circumferential molds and conical molds with a certain taper through beveling, and uses electrode wires for CNC machining, resulting in low costs and no need for manual labor, the limited cutting thickness restricts the processed dimensions. Furthermore, the limited beveling angle of the electrode wire limits the taper. Overloading can easily burn out the electrode wire, and existing wire EDM equipment only has longitudinal and transverse feed mechanisms, limiting its ability to process spherical arc surfaces. Therefore, how to use wire EDM equipment to process large and medium-sized large-tapered and circumferential punches with spherical arc surfaces has become an unsolved problem. Utility Model Content

[0004] To overcome the shortcomings of the existing technology, this utility model provides a circumferential wire cutting device capable of processing large and medium-sized circumferential punches with arbitrary taper and spherical arc surfaces.

[0005] A circular wire EDM device includes: a fast wire EDM mechanism, a transverse feed mechanism, a working fluid recovery tank, a base, a crossbeam, a longitudinal feed mechanism, a support rod, a longitudinal beam, a slow wire EDM mechanism, a workpiece, a rotary feed mechanism, a pulse power supply, and a CNC device. The fast wire EDM mechanism is located on the right rear side of the base, and the slow wire EDM mechanism is located on the left rear side of the base. The left and right ends of the crossbeam are respectively fixedly connected to the inner middle sections of the fast wire EDM mechanism and the slow wire EDM mechanism. The inner side of the longitudinal beam is fixedly connected to the center of the inner side of the crossbeam. The longitudinal feed mechanism is sleeved on the longitudinal beam, forming a sliding pair. The upper side of the longitudinal feed mechanism is connected to the lower side of the transverse feed mechanism. The components are interlocked to form a sliding pair; the rotary feed mechanism is located on the upper center of the transverse feed mechanism, and the workpiece is located at the four-jaw chuck of the rotary feed mechanism; the upper end of the support rod is connected to the lower outer end of the longitudinal beam, and the lower end of the support rod is connected to the bottom of the working fluid recovery tank, which is located on the upper front side of the base; the electrode clamps of the fast wire feeding mechanism, slow wire feeding mechanism, workpiece, and rotary feed mechanism are connected to a pulse power supply via wires to form a pulse current circuit; the rotary feed motors of the transverse feed mechanism, longitudinal feed mechanism, and rotary feed mechanism are connected to a CNC device via wires to form a feed control circuit.

[0006] Both the fast wire cutting mechanism and the slow wire cutting mechanism are existing general-purpose wire cutting mechanisms; the electrode wire of the fast wire cutting mechanism is preferably molybdenum wire, and the electrode wire of the slow wire cutting mechanism is preferably copper wire.

[0007] Both the transverse feed mechanism and the longitudinal feed mechanism are existing general-purpose wire cutting feed mechanisms.

[0008] The workpiece being processed is provided with a clamping process end, the diameter of which is smaller than the cutting thickness of a general-purpose wire cutting machine, making it easy to remove after processing.

[0009] The rotary feed mechanism includes: a four-jaw chuck, an electrode clamp, a reducer, a rotary feed motor, an L-plate, a connecting sleeve, and an electrode. The input end of the reducer on the right side is connected to the rotary feed motor, and the left end of the output end on the left side is connected to the right end of the large end of the electrode on the right side. The small end of the electrode on the left side is located inside the connecting sleeve. The right end of the connecting sleeve is connected to the left end of the large end of the electrode on the right side, and the left side is fitted into the central hole of the four-jaw chuck. The electrode clamp is connected to a pulse power supply via a wire, and its inner hole is fitted into the outer circle of the large end of the electrode on the right side. The lower mounting plate is bolted to the upper part of the L-plate. The right side of the L-plate is connected to the lower support of the reducer, and the lower support is connected to the transverse feed mechanism.

[0010] The electrode clamp includes: a copper clamp, an inner liner, a nut, and a bolt; the inner liner is located inside the copper clamp, the bolt is fitted into the mounting holes of the two mounting plates on the lower side of the copper clamp, and the nut is located outside the mounting plate on the lower side of the copper clamp and fitted into the right end of the bolt; the copper clamp is welded or lapped with wires to connect to the pulse power supply.

[0011] The copper clamp has an open circular ring on the upper side and two mirror-symmetrical mounting plates on the lower side, with the mounting holes on the two mounting plates aligned with each other; the material is elastic brass.

[0012] The lining material is graphite packing for valves and pumps.

[0013] The reducer is a continuously variable transmission (CVT).

[0014] The rotary feed motor is a continuously variable speed motor that can rotate in both directions and is adapted to a reciprocating wire feeding mechanism.

[0015] The upper side of the L-plate has mounting holes for fitting bolts.

[0016] The electrode includes: a mandrel, a copper sleeve, a partition, and a spacer ring; the mandrel is embedded in the central hole of the copper sleeve, and the top of the mandrel is located inside the central hole of the copper sleeve; the partition is located on the right side of the large end of the right side of the copper sleeve, and the spacer ring is located on the left side of the large end of the right side of the copper sleeve and is sleeved on the small end of the left side of the copper sleeve.

[0017] The mandrel is a heat-treated high-strength alloy steel cylindrical pin, slightly shorter than the copper sleeve.

[0018] The copper sleeve is a cylindrical structure with a stepped center hole on the left and a larger center hole on the right, and is made of brass.

[0019] The partition is a disc structure that connects the right end of the copper sleeve to the output end of the reducer. It is made of glass fiber filled polypropylene.

[0020] The spacer ring is a circular ring structure that connects the right end of the connecting sleeve to the left end of the large right end of the copper sleeve. It is made of glass fiber filled polypropylene.

[0021] Based on existing wire EDM equipment, this utility model makes full use of the original longitudinal and transverse feed mechanisms and adds a rotary feed mechanism. By drawing on the principle of CNC machining, the wire EDM equipment can process large and medium-sized arbitrarily tapered and circumferential punches with spherical arc surfaces, with higher processing accuracy, higher working efficiency, wider processing range, and is more suitable for batch processing.

[0022] The working principle of this utility model is as follows: In the roughing and semi-finishing processes of this invention, the workpiece is first placed against the electrode and then clamped using a four-jaw chuck. The fast wire EDM mechanism and rotary feed motor are then activated. The rotary feed motor drives the workpiece to rotate via a reducer. After adjusting the reducer to the optimal speed for dynamic balance, the transverse and longitudinal feed mechanisms are activated to move the workpiece to the right of the electrode wire of the fast wire EDM mechanism. The electrode wire performs electrical discharge machining on the surface of the rotating workpiece using pulse discharge, similar to progressive machining in turning, leaving a finishing allowance. During roughing and semi-finishing, the linear speed at which the rotary feed motor drives the workpiece to rotate... The wire feed direction is aligned with the wire feed direction, reducing the relative speed difference between the workpiece and the electrode wire. This increases the electrical discharge time at the machining position, deepening the ablation layer and improving the efficiency of roughing and semi-finishing. For fast wire feed mechanisms, molybdenum wire is preferred. Molybdenum wire is a multi-stage electrode wire with strong ablation resistance, effectively increasing the pulse current during roughing and semi-finishing, deepening the ablation layer, and improving the efficiency of these processes. During roughing and semi-finishing, the machine operator must use calipers to check the diameter of the molybdenum wire regularly. If the diameter exceeds the tolerance, it should be replaced promptly to prevent excessively ablated molybdenum wire from breaking during use and causing accidents.

[0023] After roughing and semi-finishing, the transverse feed mechanism and the longitudinal feed mechanism move the workpiece to the left to the electrode wire of the slow wire feeding mechanism for finishing. During finishing, the linear velocity of the workpiece driven by the rotary feed motor is opposite to the wire feeding direction. The relative speed difference between the workpiece and the electrode wire increases, the electrical discharge time at the machining position is shortened, which can effectively reduce the thickness of the ablation layer and effectively improve the machining accuracy and surface finish.

[0024] This invention utilizes CNC lathe speed stabilization technology (CNC lathes can stabilize the cutting speed of conical and spherical machining by adjusting the spindle speed) to stabilize the wire cutting speed. When the electrode wire approaches the center of the workpiece, the CNC device controls the rotary feed motor to decelerate appropriately; when the electrode wire moves away from the center of the workpiece, the CNC device controls the rotary feed motor to accelerate appropriately, controlling the relative speed difference between the workpiece and the electrode wire to stabilize the wire cutting speed. During roughing and semi-finishing, due to the poor centering of the workpiece shape, the CNC device should not deviate too much from the optimal dynamic balance speed when controlling the rotary feed motor speed to avoid vibration. During finishing, since the workpiece shape is already centered and the dynamic balance is greatly improved, the CNC device should primarily focus on stabilizing the wire cutting speed when controlling the rotary feed motor speed.

[0025] After finishing, the process end of the workpiece is cut off, and then the fitter grinds and assembles it.

[0026] Compared with existing related technologies, this utility model has the following advantages: This utility model has a wide processing range: Based on the existing longitudinal and transverse feed mechanisms of wire EDM equipment, this utility model adds a rotary feed mechanism. Under the control of the CNC device, it can feed in three directions simultaneously: longitudinal and transverse linear feed and axial rotary feed, achieving a similar turning effect. It can process large and medium-sized arbitrarily tapered circumferential punches with spherical arc surfaces that cannot be processed by existing wire EDM equipment; it can also process the outer circles of circumferential workpieces such as arc-section rollers, corrugated plate rollers, ball valve cores, inner rings of spherical bearings, and lathe centers.

[0027] This invention features high machining precision: similar to progressive turning, the external dimensions are controlled by the CNC device operating the longitudinal and transverse feed mechanisms and the rotary feed mechanism, avoiding machining errors caused by uneven burning of different parts of the forming electrode in EDM.

[0028] This invention offers high processing efficiency and is suitable for batch processing. In contrast, the uneven ablation of different parts of the forming electrode during EDM (Electrical Discharge Machining) accumulates errors across multiple parts, increasing the number of times the fitter needs to re-grind and ultimately leading to scrapping, resulting in smaller processing volumes. This invention, however, uses electrode wire EDM, similar to the progressive forming process of turning. The processing accuracy is unaffected by the electrode, and there is no need for mid-process re-grinding by the fitter, resulting in higher processing efficiency and making it more suitable for batch processing.

[0029] The rotary feed mechanism of this utility model takes into account both insulation and connection strength: the partition plate connects the copper sleeve and the reducer, and the spacer ring connects the connecting sleeve and the copper sleeve. Both the partition plate and the spacer ring are made of glass fiber filled polypropylene, which connects the reducer and the connecting sleeve to the electrode and provides insulation to prevent leakage. The glass fiber filling can effectively improve the strength and crack resistance of polypropylene, and the resistivity of glass fiber is higher than that of polypropylene, so it does not affect the insulation.

[0030] The electrode clamp of this utility model combines conductivity and wear resistance: the inner lining material of the electrode clamp is valve pump graphite packing, which has low resistivity, low friction coefficient and good self-lubricating effect, and can act as a sliding bearing, effectively balancing conductivity and wear resistance.

[0031] The electrode of this invention balances conductivity and structural strength: the mandrel is embedded in the central hole of the copper sleeve, and its length is slightly shorter than that of the copper sleeve, ensuring that after installation, the top of the mandrel is located inside the central hole of the copper sleeve, ensuring that the copper sleeve and the workpiece fit tightly together when clamping and machining, avoiding poor contact; the copper sleeve is made of brass, balancing conductivity and structural strength, and the mandrel is a heat-treated high-strength alloy steel cylindrical pin, which can further improve the electrode's supporting rigidity and structural strength. Attached Figure Description

[0032] Figure 1 A schematic diagram of the structure of this utility model; Figure 2 AA sectional view of this utility model; Figure 3 Schematic diagram of the rotary feed mechanism of this utility model; Figure 4 Schematic diagram of the electrode clamp structure of this utility model; Figure 5 Schematic diagram of the electrode structure of this utility model. Detailed Implementation

[0033] like Figure 1 , Figure 2 , Figure 3 , Figure 4 , Figure 5 As shown, a circular wire cutting device includes: a fast wire cutting mechanism 1, a transverse feed mechanism 2, a working fluid recovery tank 3, a base 4, a crossbeam 5, a longitudinal feed mechanism 6, a support rod 7, a longitudinal beam 8, a slow wire cutting mechanism 9, a workpiece 10, a rotary feed mechanism 11, a pulse power supply 12, and a CNC device 13; the fast wire cutting mechanism 1 is located on the right rear side of the base 4, and the slow wire cutting mechanism 9 is located on the left rear side of the base 4; the left and right ends of the crossbeam 5 are respectively fixedly connected to the inner middle sections of the fast wire cutting mechanism 1 and the slow wire cutting mechanism 9; the inner side of the longitudinal beam 8 is fixedly connected to the center of the inner side of the crossbeam 5; the longitudinal feed mechanism 6 is sleeved on the longitudinal beam 8, forming a sliding pair; the upper side of the longitudinal feed mechanism 6 and the lower side of the transverse feed mechanism 2 are sleeved together. The following components are connected to form a sliding pair: the rotary feed mechanism 11 is positioned on the upper center of the transverse feed mechanism 2, and the workpiece 10 is located at the four-jaw chuck 11-1 of the rotary feed mechanism 11; the upper end of the support rod 7 is connected to the lower outer end of the longitudinal beam 8, and the lower end of the support rod 7 is connected to the bottom of the working fluid recovery tank 3, which is located on the upper front end of the base 4; the fast wire feeding mechanism 1, the slow wire feeding mechanism 9, the workpiece 10, and the electrode clamp 11-2 of the rotary feed mechanism 11 are connected to the pulse power supply 12 via wires to form a pulse current circuit; the transverse feed mechanism 2, the longitudinal feed mechanism 6, and the rotary feed motor 11-4 of the rotary feed mechanism 11 are connected to the CNC device 13 via wires to form a feed control circuit.

[0034] Both the fast wire cutting mechanism 1 and the slow wire cutting mechanism 9 are existing general-purpose wire cutting mechanisms; the electrode wire of the fast wire cutting mechanism 1 is preferably molybdenum wire, and the electrode wire of the slow wire cutting mechanism 9 is preferably copper wire.

[0035] Both the transverse feed mechanism 2 and the longitudinal feed mechanism 6 are existing general-purpose wire cutting feed mechanisms.

[0036] The workpiece 10 is provided with a clamping process end, the diameter of which is smaller than the cutting thickness of a general-purpose wire cutting equipment, so that it can be removed after processing.

[0037] The rotary feed mechanism 11 includes: a four-jaw chuck 11-1, an electrode clamp 11-2, a reducer 11-3, a rotary feed motor 11-4, an L-plate 11-5, a connecting sleeve 11-6, and an electrode 11-7. The right input end of the reducer 11-3 is connected to the rotary feed motor 11-4, and the left output end is connected to the right end of the right large end of the electrode 11-7. The left small end of the electrode 11-7 is located inside the connecting sleeve 11-6. The right end of the connecting sleeve 11-6 is connected to the left end of the right large end of the electrode 11-7, and the left side is fitted into the middle hole of the four-jaw chuck 11-1. The electrode clamp 11-2 is connected to the pulse power supply 12 via a wire, and its inner hole is fitted into the outer circle of the right large end of the electrode 11-7. The lower mounting plate is bolted to the upper side of the L-plate 11-5. The right side of the L-plate 11-5 is connected to the lower support of the reducer 11-3, and the lower support is connected to the transverse feed mechanism 2.

[0038] The electrode clamp 11-2 includes: a copper clamp 11-2-1, an inner liner 11-2-2, a nut 11-2-3, and a bolt 11-2-4; the inner liner 11-2-2 is located inside the copper clamp 11-2-1, the bolt 11-2-4 is fitted into the mounting holes of the two mounting plates on the lower side of the copper clamp 11-2-1, and the nut 11-2-3 is located outside the mounting plate on the lower side of the copper clamp 11-2-1 and fitted into the right end of the bolt 11-2-4; the copper clamp 11-2-1 is welded or lapped with wires to connect to the pulse power supply 12.

[0039] The copper clamp 11-2-1 has an open circular ring on the upper side and two mirror-symmetrical mounting plates on the lower side, with the mounting holes on the two mounting plates aligned with each other; the material is elastic brass.

[0040] The inner lining 11-2-2 is made of valve and pump graphite packing.

[0041] The reducer 11-3 is a continuously variable transmission (CVT).

[0042] The rotary feed motor 11-4 is a continuously variable speed motor that can rotate in both directions and is adapted to a reciprocating wire feeding mechanism.

[0043] The upper side of the L-plate 11-5 has mounting holes for bolts 11-2-4.

[0044] The electrode 11-7 includes: a mandrel 11-7-1, a copper sleeve 11-7-2, a partition 11-7-3, and a spacer ring 11-7-4; the mandrel 11-7-1 is embedded in the middle hole of the copper sleeve 11-7-2, and the top of the mandrel 11-7-1 is located inside the middle hole of the copper sleeve 11-7-2; the partition 11-7-3 is located on the right side of the large end of the copper sleeve 11-7-2, and the spacer ring 11-7-4 is located on the left side of the large end of the copper sleeve 11-7-2, and is sleeved on the small end of the left side of the copper sleeve 11-7-2.

[0045] The mandrel 11-7-1 is a heat-treated high-strength alloy steel cylindrical pin, and its length is slightly shorter than that of the copper sleeve 11-7-2.

[0046] The copper sleeve 11-7-2 is a stepped cylinder with a central hole, made of brass.

[0047] The partition 11-7-3 is a disc structure that connects the right end of the copper sleeve 11-7-2 to the output end of the reducer 11-3. The material is glass fiber filled polypropylene.

[0048] The spacer ring 11-7-4 is a circular ring structure that connects the right end of the connecting sleeve 11-6 to the left end of the right large end of the copper sleeve 11-7-2. The material is glass fiber filled polypropylene.

Claims

1. A circumferential wire cutting device, comprising: The system comprises a fast wire EDM mechanism, a transverse feed mechanism, a working fluid recovery tank, a base, a crossbeam, a longitudinal feed mechanism, a support rod, a longitudinal beam, a slow wire EDM mechanism, a workpiece, a rotary feed mechanism, a pulse power supply, and a CNC device. The crossbeam is fixedly connected to the inner middle sections of the fast wire EDM mechanism and the slow wire EDM mechanism at both ends, and the inner side of the longitudinal beam is connected to the center of the inner side of the crossbeam. The longitudinal feed mechanism is sleeved on the longitudinal beam, with its upper side and the lower side of the transverse feed mechanism interlocked. The support rod connects the lower outer end of the longitudinal beam to the bottom of the working fluid recovery tank, which is located on the upper front side of the base. The fast wire EDM mechanism is located on the right rear side of the base, and the slow wire EDM mechanism is located on the left rear side of the base. The rotary feed mechanism is positioned on the center of the upper side of the transverse feed mechanism, and the workpiece is located at the four-jaw chuck of the rotary feed mechanism. The electrode clamps of the fast wire EDM mechanism, the slow wire EDM mechanism, the workpiece, and the rotary feed mechanism are connected to the pulse power supply via wires, and the rotary feed motors of the transverse feed mechanism, the longitudinal feed mechanism, and the rotary feed mechanism are connected to the CNC device via wires.

2. The circumferential wire cutting device according to claim 1, characterized in that: The rotary feed mechanism includes: a four-jaw chuck, an electrode clamp, a reducer, a rotary feed motor, an L-plate, a connecting sleeve, and an electrode. The right input end of the reducer is connected to the rotary feed motor, and the left output end is connected to the right end of the electrode. The small end of the electrode is located inside the connecting sleeve. The right end of the connecting sleeve is connected to the left end of the large end of the electrode, and the left side is fitted into the central hole of the four-jaw chuck. The electrode clamp is connected to a pulse power supply via a wire, and its inner hole is fitted into the outer circle of the large end of the electrode on the right side. The lower mounting plate is bolted to the upper part of the L-plate. The right side of the L-plate is connected to the lower support of the reducer, and the lower support is connected to the transverse feed mechanism.

3. A circumferential wire cutting device according to claim 1 or 2, characterized in that: The electrode includes: a mandrel, a copper sleeve, a partition, and a spacer ring; the mandrel is embedded in the central hole of the copper sleeve, and the top of the mandrel is located inside the central hole of the copper sleeve; the partition is located on the right side of the copper sleeve, and the spacer ring is located on the left side of the large end of the right side of the copper sleeve and is sleeved on the small end of the left side of the copper sleeve.

4. The circumferential wire cutting device according to claim 3, characterized in that: The length of the mandrel is slightly shorter than that of the copper sleeve.

5. A circumferential wire cutting device according to claim 4, characterized in that: The copper sleeve is a cylindrical tube with a stepped center hole, smaller on the left and larger on the right.

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