Automatic wire drawing trolley for automatic wire threading EDM wire cutting machine

Abstract

An automatic wire-clamping trolley for an automatic wire-threading electric spark wire cutting machine tool is characterized in that: the wire-clamping trolley is specially designed with a built-in wire clamping structure for clamping and clamping the electrode wire, and the structure is mainly composed of a lever, a compression spring, a pressure plate, and a guide groove provided on the wire-clamping trolley. The built-in wire clamping structure uses the lever principle to clamp and fix the electrode wire through the cooperation of the pressure plate and the guide groove, and can provide a stable and reliable clamping force. The wire-clamping trolley is also provided with an externally connected swing shaft, a guide wheel and an electrode wire head detector. In coordination with the automatic wire feeding mechanism of the machine tool, the wire clamping mechanism of the wire-clamping trolley can be automatically opened, the spatial posture can be adjusted, and the position of the electrode wire head can be detected. This solution can better solve the problem of the reliability of automatic wire threading in the lower wire drawing path.

Description

Technical Field

[0001] The present invention relates to the technical field of wire-cut electric discharge machining, and in particular to an automatic wire-threading CNC reciprocating wire-cut electric discharge machine tool. In the process of automatic wire threading, the trolley can realize the functions of automatic wire clamping, automatic wire measurement, automatic wire drawing, and posture adjustment from the lower part of the main wheel of the machine tool lower wire arm to the lower part of the wire drum in coordination with the corresponding electromechanical control unit of the machine tool automatic wire threading system. Background Art

[0002] As a metal cutting processing equipment, CNC reciprocating wire EDM (abbreviated as: EDM Wire Cutting Machine) occupies an important position in industrial production. EDM wire cutting uses a continuously moving thin metal wire (called electrode wire) as an electrode to perform pulsed spark discharge to erode metal and cut the workpiece into shape. Wire threading is required before or during the wire cutting process. At present, most EDM Wire Cutting Machines can only use manual threading. Manual threading is highly professional and requires professional operation. The process is complicated, the requirements are high, the workload is large, and the efficiency is low. To this end, in recent years, technicians in this field have been working hard to research and develop fully automatic threading devices and methods suitable for EDM Wire Cutting Machines. Fully automatic threading is a complex and meticulous system engineering in the field of EDM Wire Cutting Technology. It has high process requirements, many difficulties, and high technical difficulty. It has long been a technical problem in this field. Among them, how to realize automatic threading from the lower part of the main wheel of the machine tool lower wire arm to the lower part of the wire drum is one of the technical difficulties that need to be overcome. In the prior art, automatic wire threading is usually achieved by using a wire guide tube as a guide and pushing a pair of rollers and a fluid jet guide. This method not only has a long wire feeding path and a slender electrode wire, but also the mechanism of this method is easily blocked by viscous spark erosion products. Therefore, the electrode wire is prone to instability and bending during the feeding process, or is often blocked, resulting in failure of automatic wire threading. In addition, the mechanism of this method is also relatively complicated.

[0003] In view of this, the present invention proposes a specially designed automated wire clamping and drawing trolley, which realizes automatic wire clamping, automatic wire measuring, automatic wire drawing and other automated operations from the lower part of the main wheel of the machine tool's lower wire arm to the lower part of the wire drum in coordination with the corresponding electromechanical control unit of the machine tool's automatic wire threading, providing a new and effective way to solve this technical difficulty. Summary of the invention

[0004] The invention provides an automatic wire-clamping trolley for an automatic wire-threading electric spark wire cutting machine, which aims to solve the problem of automatic wire-threading reliability in a path from the lower part of a main guide wheel of a lower wire arm of the machine tool to the lower part of a wire drum.

[0005] To achieve the above-mentioned purpose, the technical solution adopted by the present invention is: an automatic wire-drawing trolley for an automatic wire-threading electric spark wire cutting machine, the innovation of which lies in: the wire-drawing trolley has a base, and the front-to-back direction of the base is defined as the X-axis direction, the left-to-right direction is the Y-axis direction, and the up-down direction is the Z-axis direction with the center of the base as the base point.

[0006] A lever is arranged on the base along the X-axis direction. The lever is rotatably supported on the base through a first support shaft at a fulcrum. The axis of the first support shaft is parallel to the Y-axis direction, so that the lever can swing relative to the base in a plane perpendicular to the Y-axis direction.

[0007] A pressing piece is arranged at the front end of the lever, and the pressing piece is connected to the front end of the lever in a rotational manner around the Y-axis direction, so that the pressing piece can swing relative to the lever in a plane perpendicular to the Y-axis direction. A second support shaft is arranged at the front end of the lever, and a through hole is opened on the pressing piece along the Y-axis direction, and the second support shaft is passed through the through hole.

[0008] A guide groove for threading the wire is opened on the base along the X-axis direction, and the lower part of the pressing sheet extends into the guide groove. The two side surfaces of the pressing sheet slide with the two side surfaces of the guide groove, and a wire clamping groove is formed between the lower end surface of the pressing sheet and the corresponding groove surface of the guide groove, wherein the lower end plane of the pressing sheet is the upper wire clamping surface, and the bottom plane corresponding to the guide groove is the lower wire clamping surface.

[0009] A compression spring is arranged between the rear portion of the lever and a position corresponding to the base, and the compression spring acts in the Z-axis direction between the lever and the base.

[0010] In the assembled state, the force of the compression spring forces the lever to swing forward around the first support axis, and the second support axis drives the pressing plate to move downward as the lever swings forward, so that the upper wire clamping surface of the pressing plate is pressed against the lower wire clamping surface of the guide groove. At this time, if an electrode wire is passed between the upper wire clamping surface and the lower wire clamping surface, the electrode wire will be clamped and clamped, thereby forming a wire clamping structure built into the wire drawing trolley.

[0011] The relevant contents in the above technical solution are explained as follows:

[0012] 1. In the above scheme, a fork-shaped groove is opened at the front end of the lever along the Z-axis direction, the pressing piece is placed in the fork-shaped groove, and the second support shaft is penetrated in the through hole and positioned relative to the fork-shaped groove.

[0013] 2. In the above scheme, the lower part of the through hole on the pressing plate is a flat surface, and the second support shaft corresponding to the flat surface is a round shaft, and the flat surface is parallel to the upper wire clamping surface of the pressing plate.

[0014] 3. In the above scheme, the upper wire clamping surface of the pressing sheet is provided with a guiding angle which is beneficial to the electrode wire leading when threading the wire.

[0015] 4. In the above scheme, the front end of the guide groove is provided with a semi-open guide cone hole which is beneficial to the electrode wire leading when threading the wire.

[0016] 5. In the above scheme, a long groove is opened on the base along the X-axis direction, and the width of the long groove in the Y-axis direction is consistent with the width of the lever in the Y-axis direction. In the assembled state, the lever is placed in the long groove, and the two side surfaces between the lever and the long groove are slidably matched. When the lever swings, the long groove guides the lever in the Z-axis direction.

[0017] 6. In the above scheme, an external wire loosening power mechanism is provided for the compression spring at the rear of the lever, and the external wire loosening power mechanism is externally arranged relative to the wire clamping and drawing trolley, and the external wire loosening power mechanism has a controlled pressure output end, and the pressure output end is located at the wire loosening position set by the machine tool. In the working state, when the wire clamping and drawing trolley moves to the wire loosening position, the pressure output end acts on the rear of the lever to overcome the force of the compression spring to make the lever swing in the opposite direction around the first support shaft, and the second support shaft at the front end of the lever drives the pressing plate to move upward, thereby loosening the compressed electrode wire.

[0018] 7. In the above scheme, a wire head detector is arranged on the substrate, and an internal sensing piece and an external conducting piece are arranged on the wire head detector. The internal sensing piece is connected to the external conducting piece. When the wire head approaches or touches the internal sensing piece, the internal sensing piece triggers the corresponding wire head position detection unit of the automatic wire threading control system of the machine tool through the external conducting piece to generate a wire head in place signal.

[0019] 8. In the above scheme, the wire head detector is arranged at the rear of the pressing sheet and at the position corresponding to the guide groove, the inner sensing sheet is a contact, the contact is a conductor, the contact outer cover is provided with an insulating sleeve, the contact and the insulating sleeve are integrally fixedly installed on the base, the insulating sleeve is provided with a detection hole facing the threading part, and the contact is provided with a threading touch surface facing the detection hole. The outer conductive sheet is a detection touch surface, the insulating sleeve is provided with an open end facing the outside, the detection touch surface is arranged in the open end, and the detection touch surface is conductively connected to the contact.

[0020] In the working state, when the wire drawing trolley enters the wire clamping position set by the machine tool, the contact provided by the machine tool detection unit will touch the detection touch surface. When the front end of the electrode wire extends into the detection hole and touches the wire threading touch surface, the machine tool detection unit can detect that the electrode wire has entered the wire clamping slot of the wire drawing trolley and is in the correct position.

[0021] 9. In the above scheme, a wire guide block is arranged at the front end of the base body, and the wire guide block is fixedly connected to the base body. A conical hole for guiding the wire threading is opened at a position corresponding to the wire clamping groove along the front and rear directions of the wire clamping groove, and a wire guide hole larger than the diameter of the electrode wire is opened at the rear of the conical hole. In the working state, the electrode wire passes through the wire guide hole and enters the wire clamping groove under the guidance of the conical hole.

[0022] 10. In the above scheme, an inclined conical surface is also provided on one side of the wire guide block, and the shape and inclination angle of the inclined conical surface are adapted to the groove of the machine tool guide wheel. When the wire clamping and drawing trolley moves to the corresponding position of entering the machine tool guide wheel, the inclined conical surface enters the groove of the machine tool guide wheel. On the one hand, the inclined conical surface plays a role in blocking the electrode wire head from entering the machine tool guide wheel groove, and on the other hand, plays a role in cooperating with the tapered hole to guide the electrode wire entering the wire clamping trolley into the wire clamping groove.

[0023] 11. In the above scheme, a connecting shaft is arranged on one side surface of the base, one end of the connecting shaft is positioned and connected to the base, and the other end of the connecting shaft serves as an outwardly extending end.

[0024] A guide wheel is arranged on the other side opposite to the connected side of the base, and the guide wheel is connected to the other side of the base through a wheel axle. The guide wheel is rotatably connected to the wheel axle, and the axis of the wheel axle is parallel to the axis of the connecting shaft, and are separated by a set distance in the X-axis direction, wherein the guide wheel is located at one end of the wire clamping head of the wire drawing trolley.

[0025] 12. In the above scheme, the wire drawing trolley is provided with a wire feeding mechanism and a guide track on the machine tool, wherein:

[0026] The wire feeding and drawing mechanism has a wire feeding and drawing action end, which is rotatably connected to the outwardly protruding end of the connecting shaft in the direction around the axis of the connecting shaft.

[0027] The guide rail is laid on the machine tool along the wire drawing path, and the guide wheel is located in the guide rail.

[0028] When in working state, the wire feeding and drawing mechanism drives the wire clamping and drawing trolley to move forward or backward through the feeding and drawing action end. During the operation of the wire clamping and drawing trolley, the guide wheel moves along the guide track, and the base body can swing around the axis of the connecting shaft to guide the swing of the head of the wire clamping and drawing trolley, thereby changing the base body posture of the wire clamping and drawing trolley and meeting the requirements for the spatial posture change of the wire clamping and drawing trolley during the automatic wire threading process of the machine tool.

[0029] The design principle and technical concept of the present invention are: in order to solve the reliability problem of automatic wire threading in the path from the lower part of the main wheel of the machine tool lower wire arm to the lower part of the wire drum, the most prominent feature of the present invention is that a wire drawing trolley for automatic wire threading is specially designed for a specific wire threading path, and a built-in wire clamping structure for clamping and clamping the electrode wire is specially designed on the wire drawing trolley. The built-in wire clamping structure is mainly composed of a lever, a compression spring, a pressing plate, and a guide groove arranged on the base of the wire drawing trolley. The built-in wire clamping structure uses the lever principle to clamp and fix the electrode wire through the pressing plate and the guide groove. The built-in wire clamping structure can not only provide a stable and reliable clamping force, but also can move with the wire drawing trolley and maintain a clamped and fixed state for a long time without external intervention. The wire drawing trolley is also designed with a wire guide block structure and a wire head detector. The wire guide block structure is used to guide the electrode wire to thread, and the wire head detector is used to detect whether the electrode wire is threaded in place. In addition, the automatic wire threading system of the machine tool is also designed with an external wire loosening power mechanism, a wire feeding and drawing mechanism, and a guide track. The external wire loosening power mechanism is used to loosen the built-in wire clamping structure, the wire feeding mechanism is used to pull the wire clamping trolley, and the guide rail is used to guide the direction of the wire clamping trolley and adjust the posture of the wire clamping trolley. Through the design of the adjustable posture of the wire clamping trolley, when the wire clamping trolley runs to the wire connecting position, the wire clamping trolley is in a vertical posture, and its front end can directly guide and clamp the electrode wire head delivered vertically, avoiding the need for the electrode wire to be turned and guided before being sent into the wire clamping trolley, greatly improving the reliability of automatic wire threading. In the process of pulling the electrode wire behind the wire clamping trolley, the electrode wire can be directly fed into the wire barrel clamp of the machine tool through the running trajectory and posture changes of the wire clamping trolley, avoiding the auxiliary action of using other mechanisms to feed the electrode wire into the wire barrel clamp.

[0030] Due to the application of the above scheme, the present invention has the following advantages and effects compared with the prior art:

[0031] 1. The built-in wire clamping structure of the present invention adopts a spring and a lever to increase the force, which can generate a larger clamping force under a smaller shape, so that the wire clamping trolley has a compact structure and a small size.

[0032] 2. The built-in wire clamping structure designed on the wire clamping trolley of the present invention can provide built-in clamping force, and can reliably clamp the wire without providing external force, and maintain the clamping fixed state for a long time, which is convenient for the automatic operation of the wire clamping trolley. If the wire clamping trolley itself uses gas, liquid, or electricity as power to clamp the wire, it will inevitably pull the gas, liquid, or electricity pipelines, affecting the flexibility and reliability of the movement of the wire clamping trolley.

[0033] 3. The pressing plate of the present invention adopts a floating design (that is, the lower part of the through hole on the pressing plate is a flat surface, the second support shaft corresponding to the flat surface is a round shaft, and the flat surface is parallel to the upper wire clamping surface of the pressing plate), which can clamp the wire evenly over the entire length of the wire clamping section without causing bending to the wire head, affecting the subsequent repeated wire threading and reducing the success rate of wire threading.

[0034] 4. The present invention can automatically and reliably open the built-in wire clamping structure on the wire drawing trolley by arranging an external wire loosening power mechanism at the wire loosening position of the machine tool for automatic wire threading, thereby realizing automatic clamping and releasing of the wire.

[0035] 5. The present invention sets a connecting shaft and a guide wheel which cooperate with the wire feeding mechanism and the guide rail of the machine tool. Under the guidance of the wire feeding mechanism of the machine tool, during the operation of the wire drawing trolley, the wire drawing trolley changes its posture by swinging around the connecting shaft and guiding the guide wheel by the guide rail, thereby meeting the need for changing the spatial posture of the wire drawing trolley during the automatic wire threading process of the machine tool.

[0036] 6. The present invention is provided with a wire head position detector for the electrode wire, which can automatically detect whether the wire head of the electrode wire enters the wire clamping groove of the wire drawing trolley in coordination with the machine tool detection unit, and at the same time accurately sense and control the position of the wire head, thereby achieving accurate and reliable wire clamping and ensuring the stability and reliability of automatic wire threading of the machine tool.

[0037] 7. The present invention arranges an inclined cone surface structure at the head of the wire drawing trolley. When the wire drawing trolley moves to the guide wheel of the machine tool, it can block the electrode wire head from entering the groove of the guide wheel of the machine tool when it moves downward, and at the same time cooperate with the tapered hole to guide the electrode wire into the wire clamping groove, thereby improving the reliability of wire threading. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Attached Figure 1 This is a first-view stereoscopic diagram of a wire drawing trolley according to an embodiment of the present invention;

[0039] Attached Figure 2 This is a stereoscopic view of the wire drawing trolley from a second viewing angle according to an embodiment of the present invention;

[0040] Attached Figure 3 This is a front view of the wire drawing trolley according to an embodiment of the present invention;

[0041] Attached Figure 4 A top view of a wire drawing trolley according to an embodiment of the present invention;

[0042] Attached Figure 5 This is a left view of the wire drawing trolley according to an embodiment of the present invention;

[0043] Attached Figure 6 This is a left view of the wire drawing trolley according to an embodiment of the present invention;

[0044] Attached Figure 7 This is a bottom view of the wire drawing trolley according to an embodiment of the present invention;

[0045] Attached Figure 8 for Figure 7 AA section view in;

[0046] Attached Fig. 9 for Figure 8 BB section view in;

[0047] Attached Fig.10 This is a schematic diagram of the detection principle of the wire head detector of the wire drawing trolley according to an embodiment of the present invention;

[0048] Attached Fig.11 This is a schematic diagram of the horizontal posture of the wire drawing trolley according to an embodiment of the present invention;

[0049] Attached Fig.12 This is a schematic diagram of the upward posture of the head of the wire drawing trolley according to an embodiment of the present invention;

[0050] Attached Fig.13 This is a schematic diagram of the vertical posture of the wire drawing trolley according to an embodiment of the present invention;

[0051] Attached Fig.14 It is a schematic diagram of the downward posture of the head of the wire drawing trolley according to an embodiment of the present invention.

[0052] In the above figures: 1. Wire drawing trolley; 2. base; 3. long groove; 4. lever; 5. first support shaft; 6. fork-shaped groove; 7. pressing plate; 8. through hole; 9. second support shaft; 10. guide groove; 11. wire clamping groove; 12. upper wire clamping surface; 13. lower wire clamping surface; 14. compression spring; 15. flat surface; 16. contact; 17. insulating sleeve; 18. detection hole; 19. detection touch surface; 20. wire threading touch surface; 21. wire guide block; 22. tapered hole; 23. wire guide hole; 24. oblique tapered surface; 25. connecting shaft; 26. guide wheel; 27. wheel axle; 28. outwardly extending end; 29. ​​electrode wire; 30. guide angle; 31. guide tapered hole. DETAILED DESCRIPTION

[0053] The present invention will be further described below in conjunction with the accompanying drawings and embodiments:

[0054] Embodiment: An automatic wire-drawing trolley for an automatic wire-threading electric spark wire cutting machine.

[0055] like Figure 1-9 As shown, the wire drawing carriage 1 has a base 2 (see Figure 1 , Figure 2 , Figure 3 and Figure 8 ), with the center of the base 2 as the base point, the front-to-back direction of the base 2 is defined as the X-axis direction, the left-right direction is the Y-axis direction, and the up-down direction is the Z-axis direction (see Figure 1 The X-axis, Y-axis and Z-axis coordinates are shown in Figure 1).

[0056] The base 2 is provided with a lever 4 along the X-axis direction. The lever 4 is rotatably supported on the base 2 through a first support shaft 5 at a fulcrum (see FIG. Figure 1 , Figure 3 and Figure 8), the axis of the first support shaft 5 is parallel to the Y-axis direction, so that the lever 4 can swing relative to the base 2 in a plane perpendicular to the Y-axis direction (see Figure 8 In this embodiment, a long groove 3 is formed on the substrate 2 along the X-axis direction (see Figure 1 , Figure 2 and Figure 8 ), the width of the long slot 3 in the Y-axis direction is consistent with the width of the lever 4 in the Y-axis direction, and the lever 4 is placed in the long slot 3 in the assembled state (see Figure 1 and Figure 8 ), and the two side surfaces of the lever 4 and the long slot 3 are slidably matched, and the long slot 3 guides the lever 4 in the Z-axis direction when the lever 4 swings.

[0057] A pressing plate 7 (see FIG. 1 ) is provided at the front end of the lever 4. Figure 1 , Figure 4 and Figure 8 ), the pressing piece 7 is connected to the front end of the lever 4 in rotation around the Y-axis direction, so that the pressing piece 7 can swing relative to the lever 4 in a plane perpendicular to the Y-axis direction. In this embodiment, the pressing piece 7 is connected to the front end of the lever 4 in rotation around the Y-axis direction by: a fork-shaped groove 6 is opened at the front end of the lever 4 along the Z-axis direction (see Figure 1 , Figure 2 and Figure 4 ), the pressing sheet 7 is placed in the fork-shaped groove 6 (see Figure 1 , Figure 4 and Figure 8 ), a through hole 8 is provided on the pressing sheet 7 along the Y-axis direction (see Figure 8 ), a second support shaft 9 is disposed in the through hole 8 and positioned relative to the fork groove 6 (see Figure 1 , Figure 2 and Figure 4 However, the present invention is not limited to providing the fork-shaped groove 6 at the front end of the lever 4. The fork-shaped groove 6 may also be provided in the pressing plate 7. Alternatively, the fork-shaped groove 6 may not be provided but the front end of the lever 4 and the pressing plate 7 may be directly connected to each other by a pin shaft after being parallel to each other.

[0058] A guide groove 10 for threading is provided on the base 2 along the X-axis direction (see Fig. 9 ), the lower part of the pressing sheet 7 extends into the guide groove 10 (see Fig. 9 ), the two side surfaces of the pressing piece 7 are slidably matched with the two side surfaces of the guide groove 10 (see Fig. 9 ), a wire clamping groove 11 is formed between the lower end surface of the pressing sheet 7 and the corresponding groove surface of the guide groove 10 (see Fig. 9 ), wherein the lower end plane of the pressing sheet 7 is the upper wire clamping surface 12 (see Fig. 9 ), the bottom plane corresponding to the guide groove 10 is the lower wire clamping surface 13 (see Fig. 9 ).

[0059] A compression spring 14 is provided between the rear portion of the lever 4 and the corresponding position of the base 2 (see Figure 2 , Figure 5 and Figure 8 ), the compression spring 14 acts in the Z-axis direction between the lever 4 and the base 2 (see Figure 8 ).

[0060] In the assembled state, the force of the compression spring 14 forces the lever 4 to swing forward around the first support shaft 5 (in Figure 8 The positive swing is clockwise swing), the second support shaft 9 drives the pressing plate 7 to press downward with the positive swing of the lever 4, so that the upper wire clamping surface 12 of the pressing plate 7 is pressed with the lower wire clamping surface 13 of the guide groove 10 (see Figure 8 ), at this time, if the electrode wire 29 is passed between the upper wire clamping surface 12 and the lower wire clamping surface 13 (see Figure 8 ), the electrode wire 29 is compressed and clamped, thereby forming a wire clamping structure built into the wire drawing trolley 1.

[0061] In this embodiment, the lower part of the through hole 8 on the pressing plate 7 is designed to be a flat surface 15, and the second support shaft 9 corresponding to the flat surface 15 is a round shaft, and the flat surface 15 is parallel to the upper wire clamping surface 12 of the pressing plate 7. Such a floating design of the pressing plate 7 can clamp the wire evenly over the entire length of the wire clamping section, without causing bending of the wire head, affecting subsequent repeated wire threading, and reducing the success rate of wire threading. In addition, in order to better guide the wire threading, the front end of the upper wire clamping surface 12 of the pressing plate 7 can be provided with a guiding angle 30 (see FIG. 2 ) that is conducive to the wire drawing of the electrode wire 29 during wire threading. Figure 8 At the same time, the front end of the guide groove 10 can also be provided with a semi-open guide cone hole 31 (see Figure 8 and Fig. 9 ).

[0062] In order to cooperate with the wire-clamping and drawing trolley 1 to loosen the wire, an external wire-loosening power mechanism (not shown in the figure) is provided for the compression spring 14 at the rear of the lever 4. The external wire-loosening power mechanism is externally arranged relative to the wire-clamping and drawing trolley 1, and the external wire-loosening power mechanism has a controlled pressure output end (for example, a cylinder, a linear motor, a solenoid valve, a linear drive mechanism, etc. that can provide a driving device for linear motion), and the pressure output end is located at the wire-loosening position set by the machine tool. In the working state, when the wire-clamping and drawing trolley 1 moves to the wire-loosening position, the pressure output end acts on the rear of the lever 4 to overcome the force of the compression spring 14 and make the lever 4 swing in the opposite direction around the first support shaft 5 (in the working state). Figure 8 In the figure, the reverse swing is the counterclockwise swing), the second support shaft 9 at the front end of the lever 4 drives the pressing sheet 7 to move upward, thereby loosening the compressed electrode wire 29.

[0063] In order to cooperate with the wire drawing trolley 1 to realize automatic wire threading, a wire head detector is arranged on the base 2, and an inner sensing piece and an outer conducting piece are arranged on the wire head detector. The inner sensing piece is connected to the outer conducting piece. When the wire head approaches or touches the inner sensing piece, the corresponding wire head position detection unit of the machine tool automatic wire threading control system is triggered through the outer conducting piece to generate a wire head in place signal. In this embodiment, specifically: the wire head detector is arranged at the rear of the pressing plate 7 and at the position corresponding to the guide groove 10, and the inner sensing piece is a contact 16 (see Figure 8 ), the contact 16 is a conductor, and the contact 16 is provided with an insulating sleeve 17 (see Figure 8 ), the contact 16 and the insulating sleeve 17 are integrally fixedly mounted on the base 2, and the insulating sleeve 17 is provided with a detection hole 18 (see Figure 8 ), the contact 16 is provided with a threading contact surface 20 facing the detection hole 18 (see Figure 8 The outer conductive sheet is a detection touch surface 19 (see Figure 8 ), the insulating sleeve 17 is provided with an open end toward the outside, the detection touch surface 19 is arranged in the open end, and the detection touch surface 19 is conductively connected to the contact 16 (see Figure 8 ).

[0064] In working state, see Fig.10 As shown in the (Schematic diagram of the detection principle of the wire head detector of the wire drawing trolley), when the wire drawing trolley 1 enters the wire clamping position set by the machine tool, the contact provided by the machine tool detection unit touches the detection touch surface 19, and when the front end of the electrode wire 29 extends into the detection hole 18 and touches the wire threading touch surface 20, the machine tool detection unit can detect that the electrode wire 29 has entered the wire clamping groove 11 of the wire drawing trolley 1 and is in the correct position. At this time, the downward pressure of the external wire loosening power mechanism on the rear end of the lever 4 can be removed, the compression spring 14 presses one end of the lever 4, and the other end of the lever 4 drives the pressing plate 7 to press and lock the electrode wire 29 in the wire clamping groove 11. It can be seen that the machine tool detection unit can automatically detect whether the wire head of the electrode wire 29 enters the wire clamping groove 11 of the wire drawing trolley 1 with the cooperation of the wire head detector, and accurately sense and control the position of the wire head, thereby achieving accurate and reliable wire clamping and ensuring the stability and reliability of automatic wire threading of the machine tool.

[0065] In order to effectively guide the threading, a wire guide block 21 (see Figure 1 , Figure 6 and Figure 8 ), the wire guide block 21 is fixedly connected to the base 2, and the wire guide block 21 is provided with a tapered hole 22 for guiding the wire threading at a position corresponding to the wire clamping groove 11 along the front-to-back direction of the wire clamping groove 11 (see Figure 1 and Figure 8 ), a wire guide hole 23 larger than the diameter of the electrode wire 29 is opened at the rear of the tapered hole 22 (see Figure 6 and Figure 8), in the working state, the electrode wire 29 is guided by the tapered hole 22, passes through the wire guide hole 23 and enters the wire clamping groove 11.

[0066] The guide wire block 21 is also provided with an oblique cone surface 24 (see Figure 1 and Figure 6 ), the shape and inclination angle of the inclined conical surface 24 are adapted to the groove of the machine tool guide wheel. When the wire drawing trolley 1 moves to the corresponding position of the machine tool guide wheel, the inclined conical surface 24 enters the groove of the machine tool guide wheel. On the one hand, the inclined conical surface 24 blocks the head of the electrode wire 29 from entering the groove of the machine tool guide wheel. On the other hand, it cooperates with the tapered hole 22 to guide the electrode wire 29 entering the wire drawing trolley 1 into the wire clamping groove 11.

[0067] In order to drive the wire drawing carriage 1 to move and adjust its posture during movement, a connecting shaft 25 (see Figure 1 , Figure 3 , Figure 5-9 ), one end of the connecting shaft 25 is positioned and connected to the base 2 (it can be fixedly connected or rotatably connected around the Z axis), and the other end of the connecting shaft 25 serves as an outwardly extending end 28.

[0068] A guide wheel 26 is arranged on the other side opposite to the connected side of the base body 2 (see Figure 1-4 and Figure 8 ), the guide wheel 26 is connected to the other side of the base 2 through the wheel axle 27, the guide wheel 26 is rotatably connected to the wheel axle 27, the axis of the wheel axle 27 is parallel to the axis of the connecting shaft 25, and are separated by a set distance in the X-axis direction, wherein the guide wheel 26 is located at one end of the wire clamping head of the wire drawing trolley 1.

[0069] The wire drawing trolley 1 is provided with a wire feeding mechanism (not shown in the figure, such as a chain sprocket traction mechanism, a belt traction mechanism, a wire rope wheel traction mechanism, a gear rack, a cylinder hydraulic cylinder traction mechanism, etc.) and a guide rail (not shown in the figure) on the machine tool, wherein:

[0070] The wire feeding and drawing mechanism comprises a wire feeding and drawing action end, which is connected to the outwardly extending end 28 of the connecting shaft 25 in a rotational direction around the axis of the connecting shaft 25 .

[0071] The guide rail is laid on the machine tool along the wire drawing path, and the guide wheel 26 is located in the guide rail.

[0072] In working state, see Fig.11As shown in (Schematic diagram of the posture change of the wire drawing trolley), the wire feeding and drawing mechanism drives the wire drawing trolley 1 to move forward or backward through the feeding and drawing action end. During the operation of the wire drawing trolley 1, the guide wheel 26 moves along the guide track, and the base 2 can swing around the axis of the connecting shaft 25 to guide the head of the wire drawing trolley 1 to swing, thereby changing the posture of the base 2 of the wire drawing trolley 1 and meeting the requirements for the spatial posture change of the wire drawing trolley during the automatic wire threading process of the machine tool. Fig.11 It indicates that the wire drawing trolley 1 is in a horizontal posture. Fig.12 It indicates that the head of the wire drawing trolley 1 is in an upward tilted posture. Fig.13 It indicates that the wire drawing trolley 1 is in a vertical posture. Fig.14 It indicates that the head of the wire drawing trolley 1 is in a downward posture.

[0073] The above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. An automatic wire drawing trolley for an automatic wire threading electric spark wire cutting machine, characterized in that: The wire drawing trolley (1) comprises a base body (2), with the center of the base body (2) being used as a base point to define the front-to-back direction of the base body (2) as the X-axis direction, the left-to-right direction as the Y-axis direction, and the up-down direction as the Z-axis direction; A lever (4) is arranged on the base (2) along the X-axis direction. The lever (4) is rotatably supported on the base (2) at a fulcrum through a first support shaft (5). The axis of the first support shaft (5) is parallel to the Y-axis direction, so that the lever (4) can swing relative to the base (2) in a plane perpendicular to the Y-axis direction. A pressing plate (7) is arranged at the front end of the lever (4), and the pressing plate (7) is connected to the front end of the lever (4) in a rotational manner around the Y-axis direction, so that the pressing plate (7) can swing relative to the lever (4) in a plane perpendicular to the Y-axis direction; A second support shaft (9) is provided at the front end of the lever (4), a through hole (8) is opened on the pressing plate (7) along the Y-axis direction, and the second support shaft (9) is inserted into the through hole (8); A guide groove (10) for threading a wire is provided on the base (2) along the X-axis direction, the lower part of the pressing plate (7) extends into the guide groove (10), the two side surfaces of the pressing plate (7) are slidably matched with the two side surfaces of the guide groove (10), and a wire clamping groove (11) is formed between the lower end surface of the pressing plate (7) and the corresponding groove surface of the guide groove (10), wherein the lower end plane of the pressing plate (7) is the upper wire clamping surface (12), and the bottom plane corresponding to the guide groove (10) is the lower wire clamping surface (13); A compression spring (14) is provided between the rear portion of the lever (4) and a position corresponding to the base (2), and the compression spring (14) acts in the Z-axis direction between the lever (4) and the base (2); In the assembled state, the force of the compression spring (14) forces the lever (4) to swing forward around the first support shaft (5), and the second support shaft (9) drives the pressing plate (7) to move downward along with the forward swing of the lever (4), so that the upper wire clamping surface (12) of the pressing plate (7) and the lower wire clamping surface (13) of the guide groove (10) are pressed together. At this time, if an electrode wire (29) is passed between the upper wire clamping surface (12) and the lower wire clamping surface (13), the electrode wire (29) is clamped and clamped, thereby forming a wire clamping structure built into the wire drawing trolley (1).

2. The wire drawing trolley according to claim 1, characterized in that: A fork-shaped groove (6) is provided at the front end of the lever (4) along the Z-axis direction, the pressing sheet (7) is arranged in the fork-shaped groove (6), and the second support shaft (9) is passed through the through hole (8) and positioned relative to the fork-shaped groove (6).

3. The wire drawing trolley according to claim 2, characterized in that: The lower part of the through hole (8) on the pressing plate (7) is a flat surface (15), and the second support shaft (9) corresponding to the flat surface (15) is a round shaft. The flat surface (15) is parallel to the upper thread clamping surface (12) of the pressing plate (7).

4. The wire drawing trolley according to claim 1, characterized in that: The front end of the upper wire clamping surface (12) of the pressing sheet (7) is provided with a guide angle (30) which is beneficial to the leading of the electrode wire (29) during wire threading.

5. The wire drawing trolley according to claim 1, characterized in that: The front end of the guide groove (10) is provided with a semi-open guide cone hole (31) which is beneficial for guiding the electrode wire (29) during wire threading.

6. The wire drawing trolley according to claim 1, characterized in that: A long groove (3) is provided on the base (2) along the X-axis direction. The width of the long groove (3) in the Y-axis direction is consistent with the width of the lever (4) in the Y-axis direction. In the assembled state, the lever (4) is placed in the long groove (3), and the two side surfaces between the lever (4) and the long groove (3) are slidably matched. When the lever (4) swings, the long groove (3) guides the lever (4) in the Z-axis direction.

7. The wire drawing trolley according to claim 1, characterized in that: An external wire loosening power mechanism is provided for the compression spring (14) at the rear of the lever (4). The external wire loosening power mechanism is externally arranged relative to the wire clamping and drawing trolley (1). The external wire loosening power mechanism has a controlled pressure output end, and the pressure output end is located at the wire loosening position set by the machine tool. In the working state, when the wire clamping and drawing trolley (1) moves to the wire loosening position, the pressure output end acts on the rear of the lever (4) to overcome the force of the compression spring (14) so ​​that the lever (4) swings in the opposite direction around the first support shaft (5), and the second support shaft (9) at the front end of the lever (4) drives the pressing plate (7) to move upward, thereby loosening the clamped electrode wire (29).

8. The wire drawing trolley according to claim 1, characterized in that: The base (2) is provided with a wire head detector, and the wire head detector is provided with an inner sensing sheet and an outer conducting sheet, the inner sensing sheet is connected to the outer conducting sheet, and when the wire head approaches or touches the inner sensing sheet, the inner sensing sheet triggers the corresponding wire head position detection unit of the machine tool automatic wire threading control system through the outer conducting sheet, thereby generating a wire head in place signal.

9. The wire drawing trolley according to claim 8, characterized in that: The wire head detector is arranged at the rear of the pressing sheet (7) and at a position corresponding to the guide groove (10); the inner sensing sheet is a contact (16), which is a conductor; an outer cover of the contact (16) is provided with an insulating sleeve (17); the contact (16) and the insulating sleeve (17) are integrally fixedly mounted on the base (2); a detection hole (18) is provided in the insulating sleeve (17) toward the wire threading position; and a wire threading touch surface (20) is provided on the contact (16) facing the detection hole (18); the outer conductive sheet is a detection touch surface (19); an open end is provided on the insulating sleeve (17) toward the outside; the detection touch surface (19) is arranged in the open end; and the detection touch surface (19) is conductively connected to the contact (16); In the working state, when the wire drawing trolley (1) enters the wire clamping position set by the machine tool, the contact point provided by the machine tool detection unit touches the detection touch surface (19), and when the front end of the electrode wire (29) extends into the detection hole (18) and touches the wire threading touch surface (20), the machine tool detection unit can detect that the electrode wire (29) has entered the wire clamping groove (11) of the wire drawing trolley (1) and is in the correct position.

10. The wire drawing trolley according to claim 1, characterized in that: A wire guide block (21) is arranged at the front end of the base body (2), and the wire guide block (21) is fixedly connected to the base body (2). The wire guide block (21) is provided with a tapered hole (22) for guiding the wire threading at a position corresponding to the wire clamping groove (11) along the front-rear direction of the wire clamping groove (11), and a wire guide hole (23) larger than the diameter of the electrode wire (29) is provided at the rear of the tapered hole (22). In the working state, the electrode wire (29) is guided by the tapered hole (22) and passes through the wire guide hole (23) to enter the wire clamping groove (11).

11. The wire drawing trolley according to claim 10, characterized in that: A conical surface (24) is also provided on one side of the wire guide block (21). The shape and inclination angle of the conical surface (24) are adapted to the groove of the machine tool guide wheel. When the wire drawing trolley (1) moves to a corresponding position where it enters the machine tool guide wheel, the conical surface (24) enters the groove of the machine tool guide wheel. The conical surface (24) not only blocks the head of the electrode wire (29) from entering the groove of the machine tool guide wheel, but also cooperates with the conical hole (22) to guide the electrode wire (29) entering the wire drawing trolley (1) into the wire clamping groove (11).

12. The wire drawing trolley according to claim 1, characterized in that: A connecting shaft (25) is provided on one side surface of the base (2), one end of the connecting shaft (25) is positioned and connected to the base (2), and the other end of the connecting shaft (25) serves as an outwardly extending end (28); A guide wheel (26) is provided on the other side opposite to the connected side of the base (2), and the guide wheel (26) is connected to the other side of the base (2) via a wheel axle (27). The guide wheel (26) is rotatably connected to the wheel axle (27), and the axis of the wheel axle (27) is parallel to the axis of the connecting shaft (25) and is spaced a set distance apart in the X-axis direction, wherein the guide wheel (26) is located at one end of the wire clamping head of the wire clamping trolley (1).

13. The wire drawing trolley according to claim 12, characterized in that: The wire drawing trolley (1) is provided with a wire feeding mechanism and a guide rail on the machine tool, wherein: The wire feeding and drawing mechanism comprises a wire feeding and drawing action end, and the wire feeding and drawing action end is connected to the outwardly extending end (28) of the connecting shaft (25) in a rotational direction around the axis of the connecting shaft (25); The guide rail is laid on the machine tool along the wire drawing path, and the guide wheel (26) is located in the guide rail; In the working state, the wire feeding and drawing mechanism drives the wire clamping and drawing trolley (1) to move forward or backward through the feeding and drawing action end. During the operation of the wire clamping and drawing trolley (1), the guide wheel (26) moves along the guide track, and the base (2) can swing around the axis of the connecting shaft (25) to guide the head of the wire clamping and drawing trolley (1) to swing, thereby changing the posture of the base (2) of the wire clamping and drawing trolley (1) to meet the requirements for the change of the spatial posture of the wire clamping and drawing trolley (1) during the automatic wire threading process of the machine tool.

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