CN107931812B

CN107931812B - Double-working-end automatic coping device for resistance spot welding electrode

Info

Publication number: CN107931812B
Application number: CN201711409635.7A
Authority: CN
Inventors: 高建; 顾扬; 顾啸; 邵东辉; 顾寅; 吴洪超; 陈林; 刘为民; 李治; 王义兵; 李耀
Original assignee: Tianjin Yangfan Technology Development Co ltd; Tianjin Haoyuan Jigao Machinery Parts Co ltd
Current assignee: Tianjin Yangfan Technology Development Co ltd; Tianjin Haoyuan Jigao Machinery Parts Co ltd
Priority date: 2017-12-22
Filing date: 2017-12-22
Publication date: 2023-08-29
Anticipated expiration: 2037-12-22
Also published as: CN107931812A

Abstract

The invention discloses a double-working-end automatic coping device for a resistance spot welding electrode, which comprises two working ends which are arranged in a working-end frame, are vertically symmetrical and have the same structure and are mutually independent, wherein each working end is matched with a coping angle compensation system and a coping positioning reference adjusting mechanism; the system for realizing cutting comprises a power input gear, a spline shaft, a ball cage, a gear shaft, a cutter carrier gear of a combined cutting tool and the like which are sequentially driven by an alternating current motor; the system for realizing the cutting displacement movement comprises a screw ball nut, a connecting plate, a supporting seat, a working end and the like which are sequentially driven by a servo motor; the grinding angle compensation system comprises two sets of stepping motors, worm gears, bolt pull rods, connecting blocks, pin shafts and the like; the coping positioning reference adjusting mechanism comprises a two-dimensional adjusting sliding table, an electrode positioning mechanism and the like. The invention has the positioning and micro-polishing capability for the surface of the electrode, the gradual increment compensation of the polishing angle and the accurate positioning capability of the polishing position of the electrode.

Description

Double-working-end automatic coping device for resistance spot welding electrode

Technical Field

The invention relates to special process equipment for repairing and grinding welding electrodes in the spot welding process, in particular to a double-working-end electrode automatic repairing and grinding device which is suitable for repairing and grinding electrodes of a straight-line moving welding tongs and swinging welding tongs in the spot welding process, and is hereinafter referred to as a repairing and grinding device for short; or, the electrode coping device can automatically coping the welding electrode of the coaxial work welding electrode and the welding electrode of the non-coaxial work swinging welding tongs.

Background

In the spot welding process, the electrode working surface is subjected to severe work cycle loads such as high temperature and high pressure, the composition and the diameter of the electrode working surface, the contact area between the electrode surface and the workpiece surface, the contact resistance and the contact thermal resistance between the electrode surface and the workpiece surface and the like are continuously changed towards the direction deviating from the process requirement, and the quality of a welding spot of a product is dynamically changed by a series of changes. In order to reduce the fundamental adverse effect on the quality of the welding spot caused by the overlarge change of the surface state of the electrode, the working surface of the electrode is polished regularly in production, so that the purpose of maintaining the dispersion of the quality of the welding spot relatively stable is achieved by limiting the diameter of the electrode and the surface state of the electrode to be fluctuated within a certain range.

The electrode grinding device is divided into a manual grinding device and an automatic grinding device; the price is greatly different due to different product types. The electrode polishing is mainly intended to achieve the following purposes: firstly, the diameter of the working surface of the electrode which is increased is restored to an initial set value, namely, the diameter of the conductive surface of the electrode is limited to fluctuate in the two electrode grinding periods, so that necessary conditions are created for ensuring the relative balance of the power feeding and heat conducting cross-section areas in the welding nugget forming process; and secondly, removing various non-electrode original materials formed on the working surface of the electrode in the spot welding process, including an alloy layer, an attachment layer and the like, and trimming the working surfaces of the two electrodes to be parallel to the surface of the workpiece at the same time so as to ensure that the contact resistance and the effective feed sectional area between the working surface of the electrode and the workpiece fluctuate within a limited range to the greatest extent, reduce the fluctuation of various welding boundary conditions and reduce the adverse effects on the welding quality caused by temperature field transfer and the like. When the manual coping device is used, the experience of a person is needed, so that the consistency and the correspondence of the diameters of the working surfaces of the two electrodes in a space state are ensured, and the parallel relation between the polished surface and the surface of a workpiece in a space virtual state at the moment is ensured, so that the manual coping device has quite difficult work. The automatic electrode grinding device does not adopt grinding angle increment compensation measures when grinding the working surface of the electrode of the swinging welding tongs, so that the following defects are also existed when the automatic electrode grinding device is applied to electrode grinding of the swinging movement welding tongs:

(1) The upper electrode and the lower electrode are coaxially and jointly clamped on the working surface of the electrode to be polished, the two sides of the upper electrode are provided with cutting edges which are parallel to each other and can rotate around the original position, relatively constant electrode pressure is always acted on the cutting edges on the two sides during electrode polishing, and the three parameters such as the rotating speed of the cutting edges, the electrode pressure, the polishing time and the like jointly determine the cutting quantity of each electrode to be polished and the like to be a common characteristic during the working of the existing electrode polisher, thereby generating various negative natural processing attributes as described in the 2 nd paragraph.

(2) Various negative attributes of the existing electrode automatic coping device are determined by common processing characteristics: firstly, the cutting tool rotates around a fixed shaft at a fixed position, the rotation axis of the cutting tool coincides with the electrode axis, a theoretical track line machined on the working surface of the electrode is provided with a helix angle, and the parallelism between the two polished electrode surfaces and the surface of the workpiece cannot be ensured; secondly, in order to reduce the adverse effect of dynamic load on the impact of the cutting edge, most of the cutting edge adopts a working mode that the cutting edge starts to rotate after electrode pressure is stably established on the cutting edge, namely the cutting edge system is started in a carrying way under the action of large electrode pressure, the rotating speed is increased from zero to the designed working rotating speed instantaneously, and the impact on the cutting edge is extremely large; thirdly, the cutting linear velocity from the outer diameter of the electrode to the cutting edge of the axial center of the electrode has the change from V=Vmax to V=0, namely the cutting linear velocity and the cutting acceleration of the outer diameter part of the electrode are the largest, and the impact on the cutting edge is the strongest; the cutting linear speed of the axial center part of the electrode is zero, the center part of the cutting edge has no cutting effect on the electrode surface, the stripping between the electrode material to be cut and the electrode surface at the position is the comprehensive result of the superposition effect of the rotating rolling and the rotating tearing of the cutting edge, and the electrode material uniformity, the conductivity, the cutting edge and the like on the electrode surface are damaged to a certain extent; fourth, in order to remove the metal to be cut at the axial center of the electrode, the length of the cutting edge must pass through the axial center in design in consideration of the factors such as the repeated positioning precision error of the electrode, the fit clearance required by the rotation of the cutting edge, and the local cutting edge exceeding the axial center bears severe working conditions such as reverse cutting and hard extrusion in the cutting process, which is extremely unfavorable for the service life of the cutting edge; fifthly, repeated positioning error precision causes offset of a pressure center, and the offset of the pressure center makes the electrode grinding surface form a certain processing deflection angle relative to the workpiece surface by utilizing a fit clearance, so that non-parallelism between the electrode working surface and the workpiece surface is increased, and adverse effects are formed on relative stability of the electrode feed cross-section area, welding spot quality and the like; sixth, because the impact stress born by the cutting tool in the electrode sharpening process is very large, the sharpness of the cutting tool edge is limited, and meanwhile, the small-cutting-amount cutting capability of the cutting tool edge is also limited, and excessive cutting is called as an absolute main body in each electrode sharpening amount.

(3) The grinding amount is determined by utilizing the matching relation of three parameters such as grinding time and the like, and the excessive cutting of the electrode material is difficult to effectively control instead of controlling the grinding cutting amount each time through grinding displacement.

4 the existing electrode automatic polishing device has no angle step-by-step automatic compensation function, and when polishing the swing type welding tongs electrode, the unevenness between the working surface of the polished electrode and the surface of the workpiece can be gradually amplified.

Disclosure of Invention

Aiming at the prior art, the invention provides a double-working-end automatic coping device for a resistance spot welding electrode, which can realize the following steps: (1) In the whole grinding process, the two electrodes are tightly attached to the positioning reference on the positioning block of the automatic electrode grinding device by the convex ring on the end face of the electrode holding rod all the time to serve as the reference in grinding and keep an open static state; before electrode grinding, the surface to be ground of the electrode is not contacted with the cutting edge of the cutting tool; when the electrode is polished, the displacement amount and the displacement precision of the two groups of the working end carrying tools moving towards the electrode surfaces at two sides determine the polishing amount and the length precision during polishing each time; the electrode dressing process is independent of electrode pressure. (2) The electrode is grinded by adopting a fixed displacement and micro-cutting mode for the linear movement type welding tongs or the swinging movement type welding tongs; (3) Electrode polishing of the swinging welding tongs is gradually increased to compensate the electrode polishing angle according to the characteristic that the electrode is gradually shortened along with polishing times, so that the timely parallelism of the polished electrode working surface and the workpiece surface in the spot welding process is ensured; (4) The grinding and cutting process is that a combined cutting tool formed by combining a cylindrical milling cutter with a cambered surface milling cutter or a round table milling cutter respectively realizes milling and grinding of the working surface and the adjacent side surface of the working end of the electrode in a revolution and autorotation mode; (5) The electrode of the swing type welding tongs is polished, and the angle displacement compensation mechanism can automatically superimpose an angle displacement increment on the working angle of the working end every time the electrode is polished according to the preset program, so that the timely parallelism between the polished electrode surface of the swing type welding tongs and the workpiece surface is ensured.

In order to solve the technical problems, the double-working-end automatic coping device for the resistance spot welding electrode comprises a bracket and a working end frame arranged on the bracket, wherein two working ends which are arranged symmetrically up and down and have the same structure are arranged in the working end frame, a coping angle compensation system is matched with each working end, and a coping positioning reference adjusting mechanism is arranged on the working end frame; the working end frame is of a combined structure type, comprises a left frame, a frame body upper plate, a right frame and a frame body lower plate, and is formed by fastening, assembling and combining locking bolts; a left guide shaft, a right guide shaft, a ball screw and a spline shaft are assembled between the upper plate of the frame body and the lower plate of the frame body through shaft holes and bearing assemblies corresponding to the upper and lower positions; the ball screw comprises two sections of spherical raceways which are symmetrical about the axial center and are mutually in positive and negative threads, and ball nuts which are mutually in positive and negative threads are respectively assembled on the two sections of spherical raceways; a spline gear is arranged at the bottom end of the spline shaft; the lower surface of the lower plate of the frame body is fixedly provided with a combination body of an alternating current motor and a speed reducer, an output shaft of the speed reducer passes through a through hole reserved on the lower plate of the frame body and then is arranged above the lower plate of the frame body, and the output shaft of the speed reducer is provided with a power input gear which is meshed with the spline gear; the working end comprises a working end body, a connecting plate fixed with one ball nut on the ball screw, and supporting seats respectively sleeved on the left guide shaft and the right guide shaft in a sliding manner, hanging shafts are arranged on two sides of the working end body, hanging shaft through holes are formed in the bottom ends of the two supporting seats, the two supporting seats are in sliding hinge connection with the working end body through shaft holes, and the two supporting seats are fixedly connected with the connecting plate through bolts; the two working ends and the side surfaces of the cavities of the two working end bodies are respectively and hermetically provided with a working end cover plate, so that the working end body and the working end cover plate connected with the working end body form a shell of the working end; a ball cage gear assembly and a tool rest gear assembly are arranged in the shell of the working end; the ball cage gear assembly comprises a gear shaft and a ball cage, the gear shaft is arranged in the working end body through a gear shaft bearing group and a corresponding bearing spacer bush, the ball cage is assembled on the spline shaft, a spline inner hole of the ball cage is in sliding fit with the spline shaft, the ball cage is provided with three half shafts, three jogging grooves matched with the three half shafts of the ball cage are formed in the inner hole of the gear shaft, the three half shafts are respectively jogged and arranged in the three jogging grooves, and a ball cage cover plate is arranged at the installation end of the ball cage on the gear shaft; the tool rest gear assembly comprises a tool rest gear, a tool rest body and a combined cutting tool; the combined cutting tool comprises a cutting tool shaft, wherein a shaft shoulder is arranged at one end of the cutting tool shaft, and a cutting tool left end bearing group, a first cutting tool, a second cutting tool, a cutting tool right end bearing group, a bevel pinion, a gasket, an elastic gasket and a nut are sequentially arranged from the inner side of the shaft shoulder of the cutting tool shaft to the other end of the cutting tool shaft; the bevel pinion is connected with the cutter shaft through a key; the tool rest gear is meshed with the gear shaft; the side wall of the cutter frame gear is provided with a cutter frame body mounting hole, a rectangular space is reserved in the cutter frame body for rotation of the cutter tools to serve as a cutter tool rotation cavity, two bearing holes for mounting bearings of the combined cutter tools are coaxially formed in two sides of the cutter frame body, the combined cutter tools are mounted in the cutter frame body through a cutter tool left end bearing group and a cutter tool right end bearing group, a first cutter tool and a second cutter tool of the combined cutter tools are positioned in the cutter tool rotation cavity, and the space of the cutter tool rotation cavity is larger than the space occupied by the first cutter tool and the second cutter tool in the combined cutter tools during rotation; the upper end and the lower end of the tool rest gear are respectively provided with a shaft shoulder, an upper angular contact ball bearing is assembled at the shaft shoulder of the upper end, a lower angular contact ball bearing is assembled at the shaft shoulder of the lower end, and a large bevel gear is assembled on the outer ring of the upper angular contact ball bearing in a matched manner; the big bevel gear is meshed with the small bevel gear; the two polishing angle compensation systems matched with the two working ends are respectively identical in structure and are respectively connected with the connecting plates on the two independent working ends; the grinding angle compensation system comprises a stepping motor fixed with the connecting plate, a worm is coaxially arranged with the output shaft of the stepping motor, the worm drives a worm wheel, the center hole of the worm wheel is a threaded hole, a threaded pull rod is assembled in the threaded hole, one end of the threaded pull rod passes through a bearing hole on the connecting plate and then reaches the other side of the connecting plate, and a connecting block is fixed at the tail part of the threaded pull rod passing through the connecting plate; the connecting block is hinged with the working end body by a pin shaft; a rolling shaft sleeve is arranged between the worm wheel and the bearing hole, a rolling shaft sleeve bearing group is arranged between the rolling shaft sleeve and the connecting plate, and the rolling shaft sleeve bearing group is axially limited by a clamp spring and is fixed on the connecting plate; the grinding positioning reference adjusting mechanism comprises a two-dimensional adjusting sliding table, the two-dimensional adjusting sliding table comprises a lower-layer vertical adjusting sliding table and an upper-layer horizontal adjusting sliding table, the lower-layer vertical adjusting sliding table is fixed with the right frame, an electrode positioning mechanism is fixed on the upper-layer horizontal adjusting sliding table and comprises a base plate, an intermediate plate, an upper wing plate and a lower wing plate, the intermediate plate is fixedly attached to the side face of the upper-layer horizontal adjusting sliding table, the upper wing plate and the lower wing plate are externally hung on the upper-layer horizontal adjusting sliding table, an upper angle plate is fixed on the upper wing plate, a lower angle plate is fixed on the lower wing plate, air cylinders are arranged at the end parts of the upper angle plate and the lower angle plate, open slots are formed in the upper angle plate and the lower angle plate, air cylinder rods of the two air cylinders penetrate through the side walls of the open slots and stretch into the open slots, V-shaped fixing faces are formed in the open slots and opposite to the side faces of the air cylinder rods, and when an electrode is ground, a small rod of the electrode is located between the air cylinder rods and the V-shaped fixing faces after the electrode is in place.

Furthermore, the double-working-end electrode automatic coping device for resistance spot welding is characterized in that a left anti-scratching support is fixedly connected between the left guide shaft and the left frame, a right anti-scratching support is fixedly connected between the right guide shaft and the right frame, and the positions of the left anti-scratching support and the right anti-scratching support in height are located between two working ends.

The first cutting tool is a cylindrical cutting tool, the spiral angles omega 1 of a plurality of spiral linear cutting edges are the same, and the relation among the diameter D1 of the cylindrical cutting tool, the number n1 of the cutting edges and the spiral angles omega 1 is as follows:

the geometrical parameters of the first cutting edge comprise a front angle alpha, a blade thickness f, a back angle sigma and a blade back width e, and the relation between the value range of the parameters and the material of the spot welding object is as follows:

the second cutting tool is a cambered surface cutting tool, and the surface of the cambered surface cutting tool is one of a convex cambered surface or a concave cambered surface; the arc radius of the arc-shaped cutting tool is matched with the arc radius of the side surface of the working end of the electrode to be cut and sharpened; the cambered surface-shaped cutting tool comprises a plurality of cutting edges with the same geometric shape; the structural dimensions of the cambered surface-shaped cutting tool comprise a cutting tool large end diameter D2, a cutting tool small end diameter D3 and the number of cutting edges n2; the relation between the value range of the structural dimension and the electrode diameter R to be cut and sharpened and the helix angle omega 2 of the cutting edge of the second cutting tool is as follows:

The second cutting tool is a round table-shaped cutting tool, and the taper angle of the round table-shaped cutting tool is matched with the taper angle of the side surface of the electrode working end to be cut and sharpened; the truncated cone-shaped cutting edge comprises a plurality of cutting edges with the same geometric shape; the structure size of the truncated cone-shaped cutting tool comprises a cutting tool large end diameter D2, a cutting tool small end diameter D3 and the number of cutting edges n3; the relation between the value range of the structural dimension and the electrode diameter R to be cut and sharpened and the back inclination epsilon of the cutting edge of the second cutting tool is as follows:

the geometrical parameters of the second cutting edge comprise a front angle lambda, a back angle delta, a blade thickness b and a blade thickness back angle theta; the relationship among the rake angle lambda, the relief angle delta, the blade thickness b and the blade thickness relief angle theta is as follows:

compared with the prior art, the invention has the beneficial effects that:

(1) The combined cutting tool is rotated at a high speed by taking the axis of the tool shaft as the shaft in the revolution process of the tool post gear by the structural combination mode of the cutting system, so that the cutting characteristic of grinding the electrode by the combined cutting tool in a revolution and high-speed rotation mode is formed, the spiral lift angle which is necessarily existed after the working surface of the electrode is ground due to the working principle in the prior art can be fundamentally eliminated, and the quality of welding spots is improved.

(2) The cutting displacement and the cutting speed are controlled by the cutting displacement moving system during electrode sharpening, so that the cutting sharpening amount of the electrode and the cutting tool cutting edge eating amount of the cutting tool can be precisely controlled by the cutting system, excessive cutting of the electrode can be effectively reduced, and the service life of the cutting tool can be prolonged.

(3) Through the coping angle compensation system, when the electrode of the swing type welding tongs is polished, the coping angle compensation system is suitable for the change of the polishing angle of the working end to gradually perform micro compensation, the timely parallelism between the working surface of the electrode and the surface of the workpiece after each polishing can be timely ensured, the effective feeding capacity of the surface of the electrode to the surface of the workpiece is improved, and the quality of welding spots is improved and the consumption of the electrode is reduced.

(4) By using the multi-edge combined cutting tool and adopting an electrode cutting mode of revolution and autorotation of the combined cutting tool, the cutting load of the cutting edge is greatly reduced under the condition of the same electrode cutting quantity, the service life of the cutting tool and the grinding quality of the electrode surface can be prolonged, and the use cost of the cutting tool is reduced.

(5) By using the trimming positioning reference fine adjustment mechanism, the influence of repeated precision errors generated by a robot or a person during electrode trimming on the position precision of the working surface of the electrode can be avoided, so that the cutting edge of the cutting tool always works under relatively balanced cutting stress, and the service life of the cutting tool and the quality of welding spots are improved.

Drawings

FIG. 1-1 is a front view of a dual working end automatic coping machine of the present invention with a setting positioning reference adjustment mechanism installed;

FIG. 1-2 is a left side view of the dual working end electrode trimmer of FIG. 1-1;

FIGS. 1-3 are right side views of the dual working end electrode trimmer of FIGS. 1-1;

FIGS. 1-4 are top views of the dual working end electrode dresser of FIGS. 1-1;

FIG. 2-1 is a front view of the working end of the dual working end electrode dresser of the present invention in principle;

FIG. 2-2 is a top view of the working end of the dual working end electrode trimmer of FIG. 2-1;

FIG. 3-1 is a front view of the structural principle of the dual working end electrode dresser blade carrier assembly of the present invention;

FIG. 3-2 is a cross-sectional view of a section B-B of the dual working end electrode dresser blade carrier assembly of FIG. 3-1;

FIG. 3-3 is a top view of the dual working end electrode dresser blade carrier assembly of FIG. 3-1;

FIG. 4-1 is a front view of a dual working end electrode dresser blade carrier of the present invention;

FIG. 4-2 is a cross-sectional view of the dual working end electrode dresser blade carrier of FIG. 4-1;

FIG. 5-1 is a cross-sectional view of a double working end electrode sharpener of the present invention having a combination blade in the shape of a circular table;

FIG. 5-2 is a cross-sectional view of the double working end electrode sharpener cambered surface combination cutting tool of the present invention;

FIG. 6-1 is an end view of a cylindrical blade in the dual working end electrode sharpener combination blade of the present invention;

FIG. 6-2 is an axial cross-sectional view of a cylindrical blade in the dual working end electrode sharpener combination blade of FIG. 6-1;

FIG. 6-3 is a three-dimensional view of a cylindrical blade in the dual working end electrode sharpener combination blade of FIG. 6-1;

FIG. 7-1 is an axial cross-sectional view of a cambered blade in a second blade of the double working end electrode sharpener of the present invention;

FIG. 7-2 is a left side view of the cambered blade in the second blade of the double working end electrode sharpener of FIG. 7-1;

FIG. 8-1 is an axial cross-sectional view of a frustoconical sharpener in a second sharpener of the dual working end electrode sharpener of the present invention;

FIG. 8-2 is a left side view of a frustoconical sharpener in the second sharpener of the dual working end electrode sharpener of FIG. 8-1;

FIG. 9 is a schematic diagram of the second blade edge configuration of the dual working end electrode sharpener of the present invention;

FIG. 10-1 is an external view of an outer convex arc electrode in a coping object of the coping machine of the invention;

FIG. 10-2 is an external view of a concave arc electrode in a coping object of the coping machine of the invention;

FIG. 10-3 is an external view of a truncated cone-shaped electrode in a coping object of the coping machine of the invention;

FIG. 11-1 is an axial cross-sectional view of the electrode cap of the present invention; an axial view of the ground electrode surface;

FIG. 11-2 is a bottom view of FIG. 11-1;

FIG. 11-3 is an enlarged view of a portion of the working surface of the electrode at B in FIG. 11-2;

FIG. 12-1 is a front view of a grinding positioning reference adjustment mechanism of the present invention;

FIG. 12-2 is a left side view of the coping positioning reference adjustment mechanism of FIG. 12-1;

FIG. 12-3 is a right side view of the coping positioning reference adjustment mechanism of FIG. 12-1;

FIG. 12-4 is a top view of the coping positioning reference adjustment mechanism of FIG. 12-1;

FIG. 12-5 is a three-dimensional view of the coping positioning reference adjustment mechanism of FIG. 12-1;

FIG. 13 is a view showing the relationship between the fine adjustment mechanism and the electrode plane in the three-dimensional axial positioning in the operating state;

fig. 14 is a three-dimensional view of a dual working end electrode trimmer of the present invention.

In the figure: 1-left frame, 2-upper plate of frame body, 3-left guide shaft, 4-step motor, 5-spline shaft, 6-spline shaft bearing set, 7-ball screw bearing set, 8-ball screw, 9-ball nut, 10-right guide shaft, 11-right frame, 12-connecting plate, 13-ball cage cover plate, 14-working end body, 15-supporting seat, 16-working end cover plate, 17-right flex support, 18-working end cover plate, 19-supporting seat, 20-working end body, 21-ball cage cover plate, 22-ball nut, 23-servo motor, 24-speed reducer, 25-alternating current motor, 26-speed reducer, 27-spline gear, 28-power input gear, 29-lower frame plate, 30-stepper motor, 31-connecting plate, 32-bolt, 33-supporting seat, 34-bolt, 35-left anti-deflection support, 36-supporting seat, 37-bolt, 38-hanging shaft, 39-hanging shaft, 40-worm wheel, 41-worm, 42-rolling shaft sleeve, 43-connecting block, 44-connecting block, 45-rolling shaft sleeve, 46-worm wheel, 47-worm, 48-anti-loosing bolt, 49-second cutting tool, 50-first cutting tool, 51-stepper motor support, 52-knife rest gear, 53-upper angle contact ball bearing, 54-large bevel gear, 55-lower angle contact ball bearing, 56-cutting tool shaft, 57-knife rest body, 58-gear shaft bearing group, 59-ball cage, 60-gear shaft, 61-bearing spacer bush, 62-pin shaft, 63-bolt pull rod, 64-clamp spring, 65-bolt pull rod bearing group, 66-bushing 1, 67-bushing 2, 68-cutter right end bearing group, 69-bevel pinion, 70-key, 71-nut, 72-elastic washer, 73-washer, 74-cutter left end bearing group, 75-cylinder, 76-upper angle plate, 77-base plate, 78-vertical adjusting hand wheel, 79-vertical adjusting screw support seat, 80-butterfly lock nut, 81-vertical adjusting screw, 82-horizontal sliding table, 83-horizontal adjusting screw 2, 84-adjusting nut, 85-bolt, 86-vertical sliding seat, 87-cylinder, 88-lower angle plate, 89-horizontal adjusting hand wheel, 90-horizontal adjusting screw support seat, 91-butterfly lock nut, 92-bolt, 93-control box, 94-bracket, 95-set screw, 96-electrode holding rod, 97-small holding rod, 98-electrode cap.

Detailed Description

The technical solution of the present invention will be described in further detail with reference to the accompanying drawings and the specific embodiments, which are only illustrative of the present invention and are not intended to limit the present invention.

The invention provides a double-working-end automatic coping device for a resistance spot welding electrode, which comprises a bracket 94, a working-end frame and a control box 93, wherein the working-end frame and the control box 93 are arranged on the bracket 94, and the working-end frame and the control box are shown in fig. 14. The working end frame is internally provided with two working ends which are arranged symmetrically up and down and have the same structure,

as shown in fig. 1-1, 1-2, 1-3 and 1-4, the working end frame is in a combined structure type, and the working end frame comprises a left frame 1, a frame body upper plate 2, a right frame 11 and a frame body lower plate 29, and is formed by fastening, assembling and combining through a locking bolt 48. Four pairs of shaft holes corresponding to each other are formed in the upper frame plate 2 and the lower frame plate 29, and the shaft holes are respectively: and the left guide shaft 3 and the right guide shaft 10 are fixedly provided with assembly holes. The structural types of the upper working end and the lower working end are identical to those of the parts assembled and combined internally, and the upper working end and the lower working end are assembled on a left guide shaft 3 and a right guide shaft 10 of the working end frame in a mirror image relationship; hereinafter, the upper working end and the lower working end are collectively referred to as working ends, and the upper working end is mainly described as an example. Each working end is matched with a polishing angle compensation system, and a polishing positioning reference adjusting mechanism is arranged on the working end frame. The two working ends of the invention are not only the assembly matrix of the main mechanical parts of the grinding device of the invention, but also the assembly and working references of the grinding angle compensation system and the grinding positioning reference adjustment mechanism.

In order to ensure the rigidity of the working end frame, as shown in fig. 1-1, a left anti-flex support 35 is fixedly connected between the left guide shaft 3 and the left frame 1 through a fastening bolt 95, a right anti-flex support 17 is fixedly connected between the right guide shaft 10 and the right frame 11 through a fastening bolt 95, and the positions of the left anti-flex support 35 and the right anti-flex support 17 in height are located between the two upper and lower working ends.

A left guide shaft 3, a right guide shaft 10, a ball screw 8 and a spline shaft 5 are assembled between the upper frame plate 2 and the lower frame plate 29 through shaft holes and bearing assemblies corresponding to the upper and lower positions; the ball screw 8 comprises two sections of spherical raceways which are symmetrical with each other by taking the axial center as a positive and negative thread, and ball nuts which are mutually positive and negative threads are respectively assembled on the two sections of spherical raceways; the bottom end of the spline shaft 5 is provided with a spline gear 27.

As shown in fig. 1-1, 1-2 and 1-3, the upper plate 2 and the lower plate 29 of the frame body are provided with installing holes of a spline shaft bearing sleeve 6 and a spline gear 27 which are corresponding to each other in upper and lower positions for assembling the spline shaft 5; the upper plate 2 of the frame body is provided with a mounting hole of the screw ball bearing sleeve 7 and a through hole of a speed reducer 24 shaft of the servo motor 23. The combined body of the alternating current motor 25 and the speed reducer 26 is fixedly arranged on the lower surface of the lower frame plate 29, an output shaft of the speed reducer 26 penetrates through a through hole reserved in the lower frame plate 29 and then reaches the upper side of the lower frame plate 29, a power input gear 28 is arranged on the output shaft of the speed reducer 26, and the power input gear 28 is meshed with the spline gear 27.

The structure of the upper working end and the lower working end is the same, the structure of the upper working end is described by taking the upper working end as an example, as shown in fig. 1-1, fig. 1-2, fig. 1-3 and fig. 2-1, the working end comprises a working end body 14, a connecting plate 12 fixed with a ball nut 9 above the ball screw 8, and supporting seats 15 and 36 respectively sleeved on the left guide shaft 3 and the right guide shaft 10 in a sliding manner, as shown in fig. 2-2, a bushing 1 66 is arranged between the supporting seat 15 and the left guide shaft 3, a bushing 2 67 is arranged between the supporting seat 36 and the right guide shaft 10, hanging shafts 38 and 39 are arranged on two sides of the working end body 14, hanging shaft through holes are arranged at the bottom ends of the two supporting seats 15 and 36, the two supporting seats 15 and 36 are in sliding hinge connection with the working end body 14 through shaft holes, and the two supporting seats 15 and 36 are fixedly connected with the connecting plate 12 through bolts.

Working end cover plates 16 and 18 are respectively connected to the upper and lower working ends and to the surfaces of the chambers of the two working end bodies 14 and 20, so that each working end is formed by the working end body 14 (or 20) and the working end cover plate 16 (or 18) connected with the working end body 14 (or 20) to form a shell of the working end.

And a ball cage gear assembly and a tool rest gear assembly are arranged in the shell of the working end.

As shown in fig. 2-1 and 2-2, the ball cage gear assembly comprises a gear shaft 60 and a ball cage 59, the gear shaft 60 is installed in the working end body 14 through a gear shaft bearing group 58 and a corresponding bearing spacer 61, the ball cage 59 is assembled on the spline shaft 5, a spline inner hole of the ball cage 59 is in sliding fit with the spline shaft 5, the ball cage 59 is provided with three half shafts, three jogging grooves matched with the three half shafts of the ball cage are arranged in the inner hole of the gear shaft 60, the three half shafts are respectively jogged and installed in the three jogging grooves, and a ball cage cover plate is arranged at the installation end of the gear shaft 60, which is positioned on the ball cage.

As shown in fig. 3-1, 3-2 and 3-3, the knife holder gear assembly includes a knife holder gear 52, a knife holder body 57 and a combination sharpener; as shown in fig. 4-1 and 4-2, the combined cutter comprises a cutter shaft 56, a shaft shoulder is arranged at one end of the cutter shaft 56, and a cutter left end bearing group 74, a first cutter 50, a second cutter 49, a cutter right end bearing group 68, a bevel pinion 69, a washer 71, an elastic washer 72 and a nut 73 are sequentially arranged from the inner side of the shaft shoulder of the cutter shaft 56 to the other end of the cutter shaft 56; the bevel pinion 69 is connected with the cutter shaft 56 by a key 70; the carriage gear 52 is meshed with the gear shaft 60; the side wall of the cutter frame gear 52 is provided with a cutter frame body 57 mounting hole, a rectangular space is reserved in the cutter frame body 57 for rotation of the cutter tool to serve as a cutter tool rotation cavity, two bearing holes for mounting a combined cutter tool are formed in the cutter frame body 57, the combined cutter tool is mounted in the cutter frame body 57 through a cutter tool left end bearing group 74 and a cutter tool right end bearing group 68, a first cutter tool 50 and a second cutter tool 49 of the combined cutter tool are positioned in the cutter tool rotation cavity, and as shown in fig. 3-1, 3-2 and 3-3, the space of the cutter tool rotation cavity is larger than the space occupied by the first cutter tool 50 and the second cutter tool 49 in the combined cutter tool during rotation; the upper end and the lower end of the tool rest gear 57 are respectively provided with a shaft shoulder, an upper angular contact ball bearing 53 is assembled at the shaft shoulder of the upper end, a lower angular contact ball bearing 55 is assembled at the shaft shoulder of the lower end, and a large bevel gear 54 is assembled on the outer ring of the upper angular contact ball bearing 53 in a matched manner; the large bevel gear 54 meshes with the small bevel gear 69.

As shown in fig. 6-1, 6-2 and 6-3, in the present invention, the first cutting tool 50 is a cylindrical cutting tool, the helix angles ω1 of the plurality of spiral linear cutting edges are the same, and the relationship among the diameter D1 of the cylindrical cutting tool, the number of cutting edges z=n1 and the helix angle ω1 is as follows:

the geometrical parameters of the cutting edge of the first cutting tool 50 comprise a front angle alpha, a blade thickness f, a back angle sigma and a blade back width e, and the relation between the value range of the parameters and the material of the spot welding object is as follows:

in the present invention, as shown in fig. 7-1 and 7-2, the second cutting tool 49 is a cambered surface cutting tool, and the surface of the cambered surface cutting tool is one of a convex cambered surface and a concave cambered surface; the arc radius of the arc-shaped cutting tool is matched with the arc radius of the side surface of the working end of the electrode to be cut and sharpened; the cambered surface-shaped cutting tool comprises a plurality of cutting edges with the same geometric shape; the structural dimensions of the cambered surface-shaped cutting tool comprise a cutting tool large end diameter D2, a cutting tool small end diameter D3 and the number Z=n2 of cutting edges; the relation between the value range of the structural dimension and the electrode diameter R to be cut and sharpened and the helix angle omega 2 of the cutting edge of the second cutting tool is as follows:

in the present invention, as shown in fig. 8-1 and 8-2, the second cutting tool 49 is a circular-table-shaped cutting tool, and the taper angle of the circular-table-shaped cutting tool is matched with the taper angle of the side surface of the working end of the electrode to be cut and sharpened; the truncated cone-shaped cutting edge comprises a plurality of cutting edges with the same geometric shape; the structure dimensions of the truncated cone-shaped cutting tool comprise a cutting tool large end diameter D2, a cutting tool small end diameter D3 and the number Z=n3 of cutting edges; the relation between the value range of the structural dimension and the electrode diameter R to be cut and sharpened and the back inclination epsilon of the cutting edge of the second cutting tool is as follows:

As shown in fig. 9, in the present invention, the geometrical parameters of the edge of the second blade 49 include a rake angle λ, a relief angle δ, a blade thickness b, and a blade thickness relief angle θ; the relationship among the rake angle lambda, the relief angle delta, the blade thickness b and the blade thickness relief angle theta is as follows:

in the present invention, as shown in fig. 1-1, 1-2 and 1-3, two coping angle compensation systems respectively associated with two working ends have the same structure and are respectively connected with the connection plates 12 and 31 on two independent working ends. Taking a polishing angle compensation system matched with a working end positioned above as an example to describe the structure, the polishing angle compensation system comprises a stepping motor 4 fixed with the connecting plate 12, as shown in fig. 2-1 and 2-2, a worm 47 is coaxially arranged with an output shaft of the stepping motor 4, the worm 47 drives a worm wheel 46, a center hole of the worm wheel 46 is a threaded hole, a threaded pull rod 63 is assembled in the threaded hole, one end of the threaded pull rod 63 passes through a bearing hole on the connecting plate 12 and then reaches the other side of the connecting plate 12, and a connecting block 44 is fixed at the tail part of the threaded pull rod 63 passing through the connecting plate 12; as shown in fig. 1-2, the connecting block 44 is hinged with the working end body 14 by a pin 62; a rolling shaft sleeve 45 is arranged between the worm wheel 46 and the bearing hole, a rolling shaft sleeve bearing group 65 is arranged between the rolling shaft sleeve 45 and the connecting plate 12, and the rolling shaft sleeve bearing group 65 is axially limited by a clamp spring 64, so that the rolling shaft sleeve bearing group 65 is fixed in the bearing hole of the connecting plate 12.

The grinding positioning reference adjusting mechanism comprises a two-dimensional adjusting sliding table, the two-dimensional adjusting sliding table can be purchased from the market, the two-dimensional adjusting sliding table comprises a lower-layer vertical adjusting sliding table and an upper-layer horizontal adjusting sliding table, the lower-layer vertical adjusting sliding table is fixed with the right frame 11, the upper-layer horizontal adjusting sliding table is fixedly provided with an electrode positioning mechanism, as shown in fig. 12-1, fig. 12-2, fig. 12-3, fig. 12-4 and fig. 12-5, the lower-layer vertical adjusting sliding table comprises a vertical sliding table seat 86, the vertical sliding table seat 86 is provided with a vertical adjusting screw rod supporting seat 79, a vertical adjusting screw rod 81 is arranged in the vertical adjusting screw rod supporting seat 79, the upper end of the vertical adjusting screw rod 81 is provided with a vertical adjusting hand wheel 78, an adjusting nut 84 is matched with the vertical adjusting screw rod 81, and a dovetail groove with a horizontal trend is formed in the adjusting nut 84; the upper layer horizontal adjustment slipway comprises a horizontal slipway 82, the horizontal slipway 82 is provided with a dovetail sliding block matched with the dovetail groove, a horizontal adjustment screw rod supporting seat 90 is arranged on the horizontal slipway 82, a horizontal adjustment screw rod 83 is arranged in the horizontal adjustment screw rod supporting seat 90, one end of the horizontal adjustment screw rod 83 is provided with a horizontal adjustment hand wheel 89, and the lower layer vertical adjustment slipway and the upper layer horizontal adjustment slipway are both provided with butterfly lock nuts. As shown in fig. 13, the electrode positioning mechanism includes a base plate 77, the base plate 77 includes a middle plate, an upper wing plate and a lower wing plate, the middle plate is attached to a side surface of the upper layer horizontal adjustment sliding table, and is fixed by a plurality of bolts 92, as shown in fig. 12-4 and 12-5, the upper wing plate and the lower wing plate are both suspended outside the upper layer horizontal adjustment sliding table, the upper wing plate is fixed with an upper corner plate 76, the lower wing plate is fixed with a lower corner plate 88, an air cylinder 75 is arranged at an end of the upper corner plate 76, an air cylinder 87 is arranged at an end of the lower corner plate 88, openings are formed in the upper corner plate 76 and the lower corner plate 88, an air cylinder rod of the air cylinder 75 penetrates through a side wall of the opening in the upper corner plate 76 to be inserted into the opening, a V-shaped fixing surface is formed in a side surface opposite to the air cylinder rod, when the two electrodes are polished, a small rod 97 of the upper electrode is positioned between the air cylinder rod and the V-shaped fixing surface, and a holding surface of the lower electrode 88 is positioned between the upper rod and the V-shaped fixing surface when the two electrodes are polished. The air cylinders 75 and 87 are used for clamping the electrode to be repaired in place, so that the position accuracy of the surface to be repaired of the electrode is ensured. After the horizontal datum is locked, the centering clamping action of the cylinder rods of the cylinders 75 and 87 and the V-shaped fixing surfaces in the upper corner plate 76 and the lower corner plate 88 ensures that each electrode grinding is performed under a uniform grinding datum.

In the invention, after an alternating current motor 25 assembled below a lower plate 29 of a working end frame body is started, the alternating current motor is synchronously rotated with a speed reducer 26 which is directly connected with the alternating current motor and assembled on the lower surface of the lower plate 29 of the frame body, and rotary power is transmitted to a spline shaft 5 through a power input gear 28 and a spline gear 27; the spline shaft 5 is assembled with the ball cage 59 in a matching way through a spline hole in the center of the ball cage 59; the three half shafts extending out of the ball cage 59 are embedded and assembled in corresponding mounting grooves in the gear shaft 60, and a meshing working pair is established between the three half shafts to transmit the rotation power received by the ball cage 59 to the gear shaft 60; the gear shaft 60 transmits the rotational power to the holder gear 52 engaged therewith. When the rotation power of the alternating current motor 25 is transmitted to the tool rest gear 52, the tool rest gear 52 carries the tool rest body 57 and the combined cutting tool arranged in the tool rest body 57 to synchronously rotate, and forms revolution of the combined cutting tool in the electrode grinding process; because the large bevel gear 54 fixedly arranged on the working end body 14 is meshed with the small bevel gear 69 in the combined cutter, and the small bevel gear 69 is bonded with the cutter shaft 56 through the key 70, the combined cutter coaxially and serially combined on the cutter shaft 56 synchronously rotates at a high speed along with the small bevel gear by taking the cutter shaft 56 as an axis according to the gear ratio relation between the large bevel gear 54 and the small bevel gear 69, so that the working characteristic of revolution and rotation of the combined cutter in the working process of the grinder is formed. In addition, a ball cage cover 13 is additionally provided on the upper surface of the gear shaft 60 in view of dust prevention of the meshing of the ball cage 59 with the gear shaft 60.

As shown in fig. 1-1, 1-2, 1-3, 1-4, 2-1 and 2-2, after the servo motor 23 of the present invention is started, the speed reducer 24 directly connected with the servo motor synchronously rotates; the output shaft end of the speed reducer 24 is directly connected with one end of the ball screw 8; the other axial end of the ball screw 8 is assembled in a bearing inner hole of the ball screw bearing sleeve 7 of the upper plate 2 of the frame body; the two sides of the axial center of the ball screw 8 are spherical raceways with positive and negative threads, and ball nuts 9 and 22 with positive and negative threads are respectively assembled on the spherical raceways on the two sides. The ball nuts 9 and 22 are fixedly assembled on the side plates of the upper connecting plate 12 and the lower connecting plate 31, respectively; two short shaft holes in the upper group of supporting seats 36 and 15 are respectively hinged with working end hanging shafts 38 on two sides of the upper working end body 14; two short shaft holes in the lower group of supporting seats 33 and 19 are respectively hinged with working end hanging shafts 39 on two sides of the lower working end body 20; the left and right sides of the connecting plate 12 are fixedly connected with the supporting seats 36 and 15 through bolts 37 respectively; the left and right sides of the connecting plate 31 are fixedly connected with the supporting seats 33 and 19 through bolts 32 respectively. When the servo electrode rotates to work, as the two ball nuts 9 and 22 are respectively fixedly assembled on the upper connecting plate 12 and the lower connecting plate 31, and the two sides of the ball-nut pair of the screw rod are mutually in positive and negative threads, the two ball nuts 9 and 22 respectively carry the upper connecting plate 12 and the lower connecting plate 31 to move oppositely, at the same speed and equidistantly corresponding to the rotation of the ball screw 8 at the fixed position; because the connecting plates 12 and 31 are respectively and fixedly connected with a group of supporting seats at the upper part and the lower part, and a sliding fit relation is established between the left guide shaft 3 and the right guide shaft 10 through long shaft holes in the supporting seats, corresponding to the rotation of the servo motor 23, the two working ends or the combined cutting tools carried by the working ends can move along the left guide shaft 3 and the right guide shaft 10 at the same speed and equidistance. By utilizing the characteristics of high subdivision precision and controllable speed of the servo motor 23, the working characteristics of controllable displacement speed or cutting speed and displacement precision or cutting quantity precision of the working end of the grinding device can be realized when the electrode is grinded.

According to the invention, the polishing angle compensation system is additionally provided for polishing the electrode of the swing type welding tongs, and by compensating the angular displacement deviation generated by the working surface of the electrode relative to the surface of the workpiece after each polishing, the timely parallelism between the surface of the electrode and the surface of the workpiece is ensured, and a necessary condition is created for ensuring the quality of welding spots. The grinding angle compensation system with two sets of structural forms and parts which are completely the same is arranged on the grinding device, two stepping motors 4 and 30 are respectively used as power, and independent working connection is respectively established between the two sets of working ends. As shown in fig. 2-1 and 2-2, the stepping electrode 4 is fixedly mounted on the outer upper surface of the upper connection plate 12 by a stepping motor mount 51; the stepper motor 4 is directly connected with the worm 47; a worm gear and worm matching working pair is formed between the worm 47 and the worm wheel 46; the center of the worm gear 46 is a threaded hole which is in threaded fit with the upper part of the bolt pull rod 63; the lower shaft end of the worm wheel 46 is tightly matched and installed in a rolling shaft sleeve 45 which can only rotate in situ; a thread matching working pair is formed between the thread inner hole of the worm wheel 46 and the thread of the bolt pull rod 63; the lower shaft end of the rolling shaft sleeve 45 is tightly matched and arranged in the bearing inner ring of the rolling shaft sleeve bearing group 65; the rolling shaft sleeve bearing group 65 is fixedly assembled in a bearing hole on the side wall of the upper connecting plate; the lower part of the rolling shaft sleeve bearing group 65 is limited by a clamp spring 64; the lower part of the bolt pull rod 63 is fixedly provided with a connecting block 44; the hinge connection between the three is made by pin 62 passing through a pin hole in the connecting block 44 and a pin hole in the raised portion of the rear of the upper working end body. When the stepping motors 4 and 30 are started, the worms 47 and 41 which are directly connected with the stepping motors 4 and 30 respectively synchronously rotate; the worm 47 and the worm 41 respectively drive worm gears 46 and 40 matched with the worm gears to rotate; because the screw working pair is arranged between the internal screw threads of the worm wheels 46 and 40 and the external screw threads of the bolt pull rod 63, the worm wheel can only carry the rolling shaft sleeve 45 to rotate by taking the axis of the rolling bearing group 65 as the shaft in the rotation process of the worm wheel, and meanwhile, the bolt pull rod 63 and the connecting blocks 44 and 43 are forced to drive the working end to rotate by taking the working end hanging shafts 38 and 39 as the shafts through the pin shaft 62. The polishing angle compensation system of the invention utilizes the characteristic of high subdivision precision of the stepping motor, and can realize the micro adjustment of the working swing angles of the working ends at two sides after each electrode polishing, namely the gradual increment compensation of the polishing angle.

In the invention, the grinding positioning reference adjusting mechanism is an auxiliary working unit of the grinding device and comprises a two-dimensional adjusting sliding table and an electrode positioning mechanism, and the whole body of the two-dimensional adjusting sliding table and the electrode positioning mechanism is fixedly assembled on the outer side of a working end frame, so that the two-dimensional adjusting sliding table has two main functions: firstly, the non-reference cutting of the grinder in the prior art is changed into the reference cutting, so that necessary conditions are created for effectively reducing excessive cutting during electrode grinding; and secondly, the tolerance length of the electrode is effectively utilized, and the utilization rate of electrode materials is improved.

As shown in fig. 12-1, 12-2, 12-3, 12-4 and 12-5, the two-dimensional adjustment sliding table is composed of two layers of standard sliding tables capable of being adjusted vertically and horizontally respectively, and the electrode positioning mechanism is integrally and fixedly arranged on the upper surface of the horizontal sliding table; the two-dimensional adjusting sliding table is fixedly arranged on the outer side face of the grinder frame through a fixing bolt. When the vertical adjusting hand wheel 78 is rotated, the vertical adjusting screw rod 81 synchronously rotates, drives the adjusting nut 84 to move along the matching surface of the adjusting nut and the vertical sliding table seat 86 in the vertical direction, and drives the horizontal sliding table seat 82 and the electrode positioning mechanism fixedly assembled on the horizontal sliding table seat 82 to synchronously move along the vertical direction through the matching relationship of the dovetail groove-dovetail sliding block between the adjusting nut 84 and the horizontal sliding table seat 82; when the horizontal adjustment hand wheel 89 is rotated, the horizontal adjustment screw 83 is rotated in synchronization, and the horizontal slide mount 82 moves along the horizontal direction of the dovetail groove sliding fit with the electrode positioning mechanism fixedly mounted on the upper surface thereof, since the movement of the adjustment nut 84 in the horizontal direction is restricted by the vertical adjustment screw 81. When the adjustment position in the vertical direction or the horizontal direction is determined, the position of the positioning unit in the vertical direction or the horizontal direction can be locked by the butterfly lock nuts 80 and 91, respectively.

The grinding positioning reference adjusting mechanism does not directly participate in electrode grinding work, and after the welding tongs serviced by the grinding device are determined, the horizontal adjustment in the grinding positioning reference adjusting mechanism adjusts the positions of the horizontal sliding seat 82 and the electrode positioning mechanism carried by the horizontal sliding seat 82 through the horizontal adjusting hand wheel 89, and is only used once when the horizontal grinding reference is adjusted for the first time, so that the accurate coordinate position of the electrode of the serviced welding tongs in the horizontal grinding is confirmed; after the grinding horizontal position reference is confirmed, the position of the welding tongs is locked by the butterfly lock nut 91 as long as the welding tongs are not replaced, and then the welding tongs are not started. The vertical adjustment in the grinding positioning reference adjusting mechanism utilizes a vertical adjusting hand wheel 78 to adjust the accurate position of the coordinates of the horizontal sliding table seat 82 and the electrode positioning mechanism carried by the horizontal sliding table seat in the vertical direction, and adjusts the consistency of the distance between the surfaces to be ground of the electrodes at the two sides of the working end of the grinder and the cutting edges of the two sets of combined cutting tools, so that the electrode materials are fully utilized; the function also only carries out one-time grinding reference positioning adjustment in the vertical direction when the electrode specification of the welding tongs served by the grinder is changed.

Fig. 1-3, 2-1, 3-1 and 3-2 show the positional relationship of the electrode dresser of the present invention with the combination of the electrode grip 96, the electrode small grip 97 and the electrode cap 98 of its processing target in the course of operation without a positioning mechanism.

FIGS. 10-1, 10-2 and 10-3 illustrate the combined relationship of the electrode small grip 97 and the electrode cap 98, and the specific cutting sharpening location of the electrode surfaces by the first and second sharpening tools 50, 49 of the sharpener of the present invention during operation; wherein the S surface represents the plane of the working surface of the electrode to be sharpened and is borne by the first cutting tool 50 in the combined cutting tool; the Q surface is a curved surface side surface jointed with the working surface of the electrode, namely corresponds to the convex arc surface, the concave arc surface or the truncated cone-shaped electrode.

Fig. 13 shows a positional relationship between the electrode plane and the axial three-dimensional positioning in the working state of the electrode grinding by the grinding positioning reference adjustment mechanism. Wherein, the plane positioning of the electrode refers to the state of the joint part of the electrode holding rod 97 and the electrode small holding rod 98 of the two side electrodes being tightly attached to the upper surface of the upper angle plate 76 and the lower surface of the lower angle plate 88 in the positioning mechanism; the axial positioning of the electrodes refers to the state when the two small electrode holding rods 98 which enter the V-shaped fixing surfaces on the upper corner plate 76 and the lower corner plate 88 of the positioning mechanism are contacted with the two inclined surfaces in the V-shaped fixing surfaces under the pushing of the cylinder rods of the cylinders 75 and 87.

FIGS. 11-1, 11-2 and 11-3 show an axial cross-sectional view of the electrode cap 98, an axial outward looking bottom view of the electrode coping surface, and a partial enlarged view of the electrode working plane after coping, respectively; the electrode coping is aimed at a surface plane S in the electrode cap 98 and a side surface curved surface Q surface joined to the S surface.

When the coping device works under the condition of no angle compensation, the two groups of working ends always keep opposite movement in mirror image relation with each other, and the two sets of tool rest gear assemblies respectively arranged in the coping device carry one tool rest assembly to synchronously move along with the working ends; each knife rest assembly is internally provided with a set of combined cutting tool; each group of combined cutting tools respectively bears the sharpening work of one electrode at the side of the working end; the working ends are all formed into a box body structure by the same working end body and working end cover plates; the mechanical parts related to the electrode cutting work are all assembled in the closed space of the working end box body formed by the working end body and the working end cover plate.

The two holes labeled M in fig. 2-2 are mounting reference holes that are not relevant to the operation of the inventive sander.

The automatic double-working-end electrode grinding device can be directly arranged on the wall surface by utilizing the side surface of the working end frame, and can be arranged on the bracket according to the requirement of a use site; the control box and the working end frame may also be mounted separately. FIG. 14 is a three-dimensional view of the dual working end electrode self-dresser of the present invention mounted in combination with a control box and a support; in the drawing, the control box 93 and the dresser of the present invention are integrally assembled to the bracket 94, which is one of the mounting forms of the dresser of the present invention.

The electric control system of the automatic double-working-end electrode grinding device can select single-chip microcomputer control or PLC control.

When the electrode automatic grinding device is used in production, various sensors can be used for controlling the automatic start and stop of the grinding device, and a manual switch can also be used for controlling the start and stop of the grinding device.

The invention relates to a double-working-end electrode automatic grinding device which is applicable to automatic grinding of a linear motion electrode and a swinging motion electrode in automatic welding tongs, manual welding tongs and fixed spot welding machines in the spot welding process. The electrode polishing device has the following characteristics in the electrode polishing process: in the working mode of the double working ends, each working end only bears the grinding of one side electrode; secondly, the control of the grinding displacement and the grinding speed can be realized through the control of the servo motor; thirdly, gradually increasing and changing the working angle of the electrode after each grinding of the working surface of the swinging welding tongs electrode can gradually increase and compensate the grinding angle; fourthly, working in a revolution and autorotation mode when the cutting tool grinds the electrode; fifthly, each cutting tool in the combined cutting tools is a multi-edge cutting tool with the number of cutting edges being more than or equal to 10; sixthly, the grinding positioning reference adjusting and locking function is achieved. The combined use of a series of technical measures determines that the grinding device has better grinding quality, lower electrode material consumption and longer service life of the cutting tool for electrodes of various welding tongs, and has positive effects on the aspects of improving the welding quality, reducing the cost of a spot welding process and the like.

The automatic grinder for the resistance spot welding electrode has the following characteristics according to the defects in the known technology:

(1) The working mode of the double working ends is as follows: the two working ends are respectively used for independently bearing the grinding work of one side electrode of the electrodes on two sides of the welding tongs, and compared with the known single working end grinding mode, the welding tongs have the following advantages: firstly, each set of multi-edge combined cutting tool is carried in each working end, and each working end or each set of combined cutting tool only bears the sharpening work of one side electrode, so that the cutting load of the cutting tool can be reduced; the electrode of the welding tongs with the same swing angle or different swing angles can be automatically polished by using the polishing angle displacement automatic compensation system of the polishing device.

(2) Cutting characteristics: the cutting characteristic of the grinder is realized by a cutting system and a cutting displacement moving system. Firstly, micro-cutting amount cutting under the positioning moving condition is realized through controlling the movement speed and movement displacement of the cutting displacement moving system, so that the aims of reducing excessive cutting of an electrode and prolonging the service life of a cutting tool are fulfilled; and secondly, by combining the working characteristics of revolution and rotation of the cutting tool and the use of the multi-edge cutting tool, the quality of the working surface of the electrode is improved, and the use cost of the cutting tool is reduced.

(3) Automatic compensation characteristic of grinding angular displacement: when the working surface of the electrode is polished once, a small deflection angle is generated on the working surface of the electrode of the swing type welding tongs relative to the surface of a fixed workpiece, so that the working surface of the electrode is not parallel to the surface of the workpiece in practice during spot welding, and further the welding quality and the electrode consumption are negatively influenced. The polishing angular displacement automatic compensation system provided by the invention can timely compensate the angular displacement deviation after each electrode polishing, so that the quality of welding spots can be effectively improved and the consumption of electrodes can be reduced.

(4) Grinding positioning reference adjusting mechanism: because of the double influences of abrasion of the electrode mounting conical surface on the welding tongs and the axial manufacturing precision of the electrode, after each pair of new electrodes are installed in the welding tongs, the offset relative to the grinding reference is larger, and the utilization rate of electrode materials is negatively influenced. The deviation can be eliminated by adjusting the trimming positioning reference fine adjustment mechanism, and the utilization rate of the electrode is improved.

In summary, the double-working-end automatic coping device for the resistance spot welding electrode solves the problems caused by the structural and working principle attributes and the like in the prior art. The working mode that the knife rest carries the combined cutting tool to rotate is established, so that the combined cutting tool in the invention revolves and rotates at high speed in the electrode grinding process, and a necessary condition is created for the use of the multi-edge cutting tool; the cutting edge of the multi-edge cutting tool is sharper and the cutting tool has high rotating speed, and the positioning, moving and cutting of the working end of the electrode under the micro-cutting-tool-volume condition is realized by combining the accurate control of the moving speed and the moving displacement of the cutting displacement; the polishing angle compensation system can compensate the polishing angle displacement of the swing type welding tongs, so that the working surface of the electrode is timely parallel to the surface of the workpiece after the electrode of the swing type welding tongs is polished. The comprehensive implementation of the technical measures of the invention not only effectively improves the service life of the cutting tool and the grinding quality of the electrode surface, but also can achieve good effects in the aspects of reducing the consumption of electrode materials, improving the quality of welding spots and the like.

Although the invention has been described above with reference to the accompanying drawings, the invention is not limited to the above-described embodiments, which are merely illustrative and not restrictive, and many modifications may be made by those of ordinary skill in the art without departing from the spirit of the invention, which fall within the protection of the invention.

Claims

1. A dual working end automatic coping device for a resistance spot welding electrode, comprising a bracket (94) and a working end frame arranged on the bracket (94), characterized in that:

the inside of the working end frame is provided with two working ends which are vertically symmetrically arranged and have the same structure, each working end is matched with a grinding angle compensation system, and the working end frame is provided with a grinding positioning reference adjusting mechanism;

the working end frame is of a combined structure type, and comprises a left frame (1), a frame body upper plate (2), a right frame (11) and a frame body lower plate (29) which are fastened and assembled through check bolts (48);

a left guide shaft (3), a right guide shaft (10), a ball screw (8) and a spline shaft (5) are assembled between the upper frame plate (2) and the lower frame plate (29) through shaft holes and bearing assemblies corresponding to the upper and lower positions; the ball screw (8) comprises two sections of spherical raceways which are symmetrical with each other by taking the axial center as a positive and negative thread, and ball nuts which are mutually positive and negative threads are respectively assembled on the two sections of spherical raceways; a spline gear (27) is arranged at the bottom end of the spline shaft (5);

A left anti-scratching support (35) is fixedly connected between the left guide shaft (3) and the left frame (1), a right anti-scratching support (17) is fixedly connected between the right guide shaft (10) and the right frame (11), and the positions of the left anti-scratching support (35) and the right anti-scratching support (17) in height are located between two working ends;

the combined body of an alternating current motor (25) and a speed reducer (26) is fixedly arranged on the lower surface of the lower frame plate (29), an output shaft of the speed reducer (26) passes through a through hole reserved in the lower frame plate (29) and then reaches the upper part of the lower frame plate (29), a power input gear is arranged on the output shaft of the speed reducer (26), and the power input gear is meshed with the spline gear (27);

the working end comprises a working end body, a connecting plate fixed with one ball nut on the ball screw (8) and supporting seats respectively sleeved on the left guide shaft (3) and the right guide shaft (10) in a sliding manner, hanging shafts are arranged on two sides of the working end body, hanging shaft through holes are formed in the bottom ends of the two supporting seats, a shaft hole is formed between the two supporting seats and the working end body in a sliding manner, and the two supporting seats are fixedly connected with the connecting plate through bolts; the two working ends are respectively and hermetically provided with a working end cover plate on the surfaces positioned outside the cavities of the two working end bodies, so that a shell of the working end is formed by the working end bodies and the working end cover plates connected with the working end bodies;

A ball cage gear assembly and a tool rest gear assembly are arranged in the shell of the working end;

the ball cage gear assembly comprises a gear shaft (60) and a ball cage (59), the gear shaft (60) is installed in the working end body through a gear shaft bearing group (58) and a corresponding bearing spacer (61), the ball cage (59) is assembled on the spline shaft (5), a spline inner hole of the ball cage (59) is in sliding fit with the spline shaft (5), the ball cage (59) is provided with three half shafts, three embedding grooves matched with the three half shafts of the ball cage are formed in the inner hole of the gear shaft (60), the three half shafts are respectively embedded and installed in the three embedding grooves, and a ball cage cover plate is arranged at the installation end of the ball cage on the gear shaft (60);

the knife rest gear assembly comprises a knife rest gear (52), a knife rest body (57) and a combined cutting tool; the combined cutting tool comprises a cutting tool shaft (56), wherein a shaft shoulder is arranged at one end of the cutting tool shaft (56), and a cutting tool left end bearing group (74), a first cutting tool (50), a second cutting tool (49), a cutting tool right end bearing group (68), a bevel pinion (69), a gasket (71), an elastic gasket (72) and a nut (73) are sequentially arranged from the inner side of the shaft shoulder of the cutting tool shaft (56) to the other end of the cutting tool shaft (56); the bevel pinion (69) is connected with the cutter shaft (56) through a key (70); the tool rest gear (52) is meshed with the gear shaft (60); a cutter holder body (57) mounting hole is formed in the side wall of the cutter holder gear (52), a rectangular space is reserved in the cutter holder body (57) for rotation of the cutter as a cutter rotation cavity, two bearing holes for mounting of combined cutter bearings are coaxially formed in two sides of the cutter holder body (57), the combined cutter is mounted in the cutter holder body (57) through a cutter left end bearing group (74) and a cutter right end bearing group (68), a first cutter (50) and a second cutter (49) of the combined cutter are positioned in the cutter rotation cavity, and the space of the cutter rotation cavity is larger than the space occupied by the first cutter (50) and the second cutter (49) in the combined cutter during rotation; the upper end and the lower end of the tool rest gear (52) are respectively provided with a shaft shoulder, an upper angular contact ball bearing (53) is arranged at the shaft shoulder of the upper end, a lower angular contact ball bearing (55) is arranged at the shaft shoulder of the lower end, and a large bevel gear (54) is arranged on the outer ring of the upper angular contact ball bearing (53) in a matched manner; the big bevel gear (54) is meshed with the small bevel gear (69);

The first cutting tool (50) is a cylindrical cutting tool, the spiral angles omega 1 of a plurality of spiral linear cutting edges are the same, and the relation among the diameter D1 of the cylindrical cutting tool, the number n1 of the cutting edges and the spiral angles omega 1 is as follows:

the geometrical parameters of the cutting edge of the first cutting tool (50) comprise a front angle alpha, a blade thickness f, a back angle sigma and a blade back width e, and the relation between the value range of the parameters and the material of a spot welding object is as follows:

the two polishing angle compensation systems matched with the two working ends are respectively identical in structure and are respectively connected with the connecting plates on the two independent working ends; the grinding angle compensation system comprises a stepping motor (4) fixed with the connecting plate, a worm (47) is coaxially arranged with an output shaft of the stepping motor (4), the worm (47) drives a worm wheel (46), a center hole of the worm wheel (46) is a threaded hole, a threaded pull rod (63) is arranged in the threaded hole, one end of the threaded pull rod (63) passes through a bearing hole on the connecting plate and then reaches the other side of the connecting plate, and a connecting block is fixed at the tail part of the threaded pull rod (63) passing through the connecting plate; the connecting block is hinged with the working end body by a pin shaft (62); a rolling shaft sleeve is arranged between the worm wheel (46) and the bearing hole, a rolling shaft sleeve bearing group is arranged between the rolling shaft sleeve and the connecting plate, and the rolling shaft sleeve bearing group is axially limited by a clamp spring and is fixed on the connecting plate;

The grinding positioning reference adjusting mechanism comprises a two-dimensional adjusting sliding table, the two-dimensional adjusting sliding table comprises a lower-layer vertical adjusting sliding table and an upper-layer horizontal adjusting sliding table, the lower-layer vertical adjusting sliding table is fixed with a right frame (11), an electrode positioning mechanism is fixed on the upper-layer horizontal adjusting sliding table, the electrode positioning mechanism comprises a base plate (77), the base plate (77) comprises a middle plate, an upper wing plate and a lower wing plate, the middle plate is fixedly attached to the side face of the upper-layer horizontal adjusting sliding table, the upper wing plate and the lower wing plate are externally hung on the upper-layer horizontal adjusting sliding table, an upper corner plate (76) is fixed on the upper wing plate, a lower corner plate (88) is fixed on the lower wing plate, air cylinders are arranged at the ends of the upper corner plate (76) and the lower corner plate (88), air cylinders penetrate through the side walls of the opening grooves and stretch into the opening grooves, V-shaped fixing faces are arranged on the side faces opposite to the air cylinders in the opening grooves, and when the electrodes are ground, the V-shaped fixing faces are located between the V-shaped fixing faces and the electrode holding faces of the electrode holding faces (97).

2. The double working end automatic sharpening machine for resistance spot welding electrodes as defined in claim 1, wherein the second blade (49) is a cambered blade, the surface of which is one of a convex cambered surface or a concave cambered surface; the arc radius of the arc-shaped cutting tool is matched with the arc radius of the side surface of the working end of the electrode to be cut and sharpened;

The cambered surface-shaped cutting tool comprises a plurality of cutting edges with the same geometric shape; the structural dimensions of the cambered surface-shaped cutting tool comprise a cutting tool large end diameter D2, a cutting tool small end diameter D3 and the number of cutting edges n2; the relation between the value range of the structural dimension and the electrode diameter R to be cut and sharpened and the helix angle omega 2 of the cutting edge of the second cutting tool is as follows:

3. the dual tip automatic sharpening machine for resistance spot welding electrodes as recited in claim 1, wherein said second blade (49) is a circular-table shaped blade having a taper angle that matches the taper angle of the electrode working tip side to be cut sharpened;

the truncated cone-shaped cutting edge comprises a plurality of cutting edges with the same geometric shape; the structure size of the truncated cone-shaped cutting tool comprises a cutting tool large end diameter D2, a cutting tool small end diameter D3 and the number of cutting edges n3; the relation between the value range of the structural dimension and the electrode diameter R to be cut and sharpened and the back inclination epsilon of the cutting edge of the second cutting tool is as follows:

4. a dual tip self-sharpening machine for resistance spot welding electrodes as defined in claim 2 or 3, wherein the geometric parameters of the cutting edge of the second blade (49) include rake angle λ, relief angle δ, edge thickness b, and edge thickness relief angle θ; the relationship among the rake angle lambda, the relief angle delta, the blade thickness b and the blade thickness relief angle theta is as follows: