CS202751B1 - Rewinding device of the wire electrode for the electrospark cutting device - Google Patents

Description

The present invention relates to an embodiment of a coil electrode winding device for an electro drill cutting device.

The rewinding device of the electrode is one of the most important parts of the electro-wire cutting devices. The achievable technological parameters, in particular cutting speed, surface roughness and equipment and programmed control of the tread electrode path, as well as shape accuracy, depend to a large extent on its conversion. In a device for winding a wire electrode from a reel to a winding reel at a constant speed, the requirement to ensure a uniform tension of the wire electrode with a pre-selected force comes to the fore.

In the prior art devices, the tensioning of the electrode is converted either by direct braking of the rotation of the unwinding disk or by using a separate tensioning mechanism. The first device has the disadvantage that it does not provide a sufficiently uniform tension of the electrode. As a result of the application of the tensioning force, the unwinding crumb is forced between the threads of the upholstery layers. The resulting variable frictional effect results in relatively large changes in the tensioning force, which negatively affects the machining process parameters. The disadvantage of this device is also that the size of the tensioning force varies with the amount of unwound roll from the unwinding roll ·

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For devices. - with a separate tensioning mechanism - the resulting 'tensioning force' is given by the sum of the force exerted in the tensioning mechanism and the force resulting from the direct deceleration of the decoupling. roll. The problem is to ensure that the tensioning mechanism is designed so that the fraction of the force generated by the primary braking of the unwinding roll is minimized. One of the known devices is converted in such a way that the wire electrode is fed from the reel. into a tensioning mechanism where it is wrapped around a pulley and a radius groove. . The rotation of this pulley is braked by an adjustable brake. The disadvantage of this device is that - due to the relatively low - friction effect in the radial groove of the rotating roller - it is necessary for the correct function that a force of 15 to 25% is exerted by braking the unwinding disc. total tension force. This causes the drawbacks described in the direct decoiler braking device to be reflected in this device as well. · Another known device for the electrode penetration is converted so that the electrode is guided between the decoiler and the decoiler. pulleys with smooth cylindrical surface. The counter-rotation of one of the pulleys is adjusted by a controlled braking point, the other pulley being resiliently pressed in order to ensure a high friction of the electrode -mmdzx pulleys did not slip. Foreword of this zariidanii oppoti. the former is that braking - the unwinding roll can be reduced to a minimum. However, it has the disadvantage that it requires a special mechanism to push the pulleys onto the 'pulley'. elektrodu.- disadvantage of the balsa-ri-denial is that to draw a large destatečna - ^-: TRCN must be přítlačná- Force-rollers to the electrode drdtovú niekoTkonásobna largely made as required Let's drink-tion force. The direct pressure force on the electrode is very flat, which can lead to a cross-section of the electrode at the initial tensioning forces, thereby reducing the electrode cross-section. deteriorates accuracy - machining.

The above-mentioned disadvantages are avoided by the ripple device of the electrode for the clawrisk impact device according to the invention. is that the mtaizi is unwound and it is stored and spun in the path of the wire electrode. . with a rotating tensioner-pulley. electrodes mounted and - connected - to the drive unit. pulley. The wrap angle between the d-rd electrode and the tensioner roller and the wrap between the electrode and the drive pulley is at least 120 °. It is also an object of the present invention that the tensioner and the drive load extend from the right-hand plate connected to the left-hand plate and form the peripheral groove of the triangular-shaped plate. acute peak angle Z = 10 ° - to 18 °.

In the first embodiment of the electrode according to the invention, the present invention has a range of commonly used electrode diameters ranging from 0.03 to. 0.3 mm, between the tensioner pulley and the high-frictional impact electrode, which makes it possible,. so that the tensile force in. wire electrode was. at one end of the belts 20 to 100 times greater than the t-thrust force on the other. At the end of the wrapping, the electrode in the circumferential groove of the n-pin pulley does not slip through this effect and uses it to extend the tensioning force so that by unwinding the unwinding disc. it generates only 1 to 5% of this force, while the major part, i.e., 95-99%, is produced by applying the braking mommn to the rotation of the tensioning pulley. This achieves a high tension uniformity. electrodes. during its development and good technological parameters of electro-machining. D-Láic preSnooti device 2202 751 is the possibility of regulating the tensioning force in the wide range, simplicity of the design of the tensioning device, simple operation during operation and the fact that the distribution of pressure forces along the circumference of the wrapping causes deformation of the cross-section pulley practically excluded.

The drive unit according to the invention achieves the required pulling rewinding force by high frictional effect between the wire electrode and the drive roller by simple conversion. This unit represents a considerable simplification of the whole rewinding device and its operation, since it does not contain auxiliary pressure thrusts. and the electrode is guided to the kinematic path in the rewinder only by wrapping around the respective rollers.

In the accompanying drawings, an exemplary embodiment of a wire electrode winding device over an electro-spark cutting device is shown, wherein FIG. 1 is a schematic drawing of a winding device with an spark gap; Fig. 2 shows an embodiment of a tensioner and a drive pulley in a view, Fig. 3 shows a different embodiment of a tensioner and a drive pulley in a view; Fig. 4 shows a section of a tensioner pulley together with a mechanical brake; drive pulley together with drive unit ·

The wire electrode rewinding device for the EDM consists of a winding disk 2 (Fig. 1) and a winding disk 2, on which a wire electrode 1 is wound. Between the winding disk 2 and the winding disk 2, . In the path of the electrode χ behind the unwinding disk 2, a tensioning roller X is mounted on the braking unit 6, which may consist of a mechanical brake (FIG. 4), an electromechanical brake, an electromagnetic brake, a braking electric motor and the like. The wrapping angle of the electrode χ on the tensioning roller χ is 180 °. Between the tensioner roller X and the spark gap χ are mounted two guide swivel castors χ. Above and below the spark gap X there are fixed guide members 6 in the path of the electrode χ. Three guide rollers χ β and a drive roller 10 connected to the drive unit 11 are mounted between the spark gap X and the reel 2. The tensioner pulley χ and the drive pulley 10 consist of a right plate 12 (FIG. 2 and 3) and a hot plate 13 «which are rigidly connected to one another and form a circumferential groove 16 of a triangular shape. profile with sharp point angle Z = 12 °.

An exemplary embodiment of a mechanical brake (FIG. 4) consists of a fixed body XX, which is fixed to the frame 25 by a fixed pin 20. A fixed ring 18 is glued to the fixed brake body 17. annular ring 18. The right plate 12 and the melting plate 13 are connected to each other by 8 bolts 24 and at the same time attached to the rotary body 19. A fixed pivot 20 is provided with a non-rotatably mounted washer 21 resting against the rotary body 19. 23. wherein a compression spring 2X is mounted between it and the washer 21;

The drive unit 11 formed by the electric motor X6 and the gearbox 15 rotates the drive roller 202 751 to the drive roller 10 by the frictional effect between the walls of the circumferential groove 16a by the electrode 1 and transmits the necessary tensile force. The reel 6 is also rotated and wound by the electrode 1 in the spark gap and machined with the electrode 1. The wire electrode 1 moves at a constant speed and is uniformly tensioned. Drdtová'elektroda. 1 is removed - from the disassembly disc 6, which is partially braked. Further, the electrode 1 is passed through. circumferential groove 16. 2. The braking unit 6 derives the required braking torque such that. The biasing spring 22 / FIG. pushes over the washer 21 onto a rotatable body 12 which presses against the felt 18. The size of the braking monet is adjusted by the force 23 by changing the prestressing of the compression spring 22 Thus, the centering of the tensioning roller 2. maintains a uniformly tensioned wire electrode 1 throughout the machining process.

Claims (2)

OBJECT OF THE INVENTION · A wire electrode device for an electric cutting device ^{comprising a} winding reel and a winding reel ¹¹ , between which a wire electrode is guided by an array of guide elements and is characterized by: that between the unwinding disc (2) and the skrittcm (7) is located in the trajectory of the electrode (1) and - connected to the braking unit (4) of the tensioning pad (3), - between iekriSo. the winding disc (9) is mounted in the path of the electrode (1) and is connected to the drive unit. ./11/ drive pulley / 10 /, while! the wrapping angle between the electrode (1) and the tension roller (3) and the wrapping angle (mm) between the electrode (1) and the drive roller (10) is at least 120 °. . 2. Rewinding - drdtovej device electrodes for the cutting of the electrode - the device according to claim 1, characterized ^ <^ i ^ _(JUCE in that the tension roller / 3 / and the drive wheel - / 10 / consists of the right plate / 12 / fixed to the - 1'avým plate. / 13 /, vytvárajáce circumferential groove / 16 / tгt, iυhtlnkkove ^h t ^{d p} ro clay with sharp top uhlomZs 1 ^ ⁰ ° ^- and 18 °.