JPH04129591U - Spot welding gun electrode polishing device - Google Patents

Abstract

(57) [Summary] [Purpose] The main purpose of the present invention is to prevent the chips of the electrode tip from being seize on the blade of the cutter that polishes the electrode tip of the welding gun. [Configuration] Electrode tips 11, 12 of spot welding gun 10
A rotary cutter 30 is provided opposite to the cutter 30 . The electrode tips 11 and 12 can be moved toward and away from the blade portions 31 and 32 of the cutter 30 in the axial direction. An oil-impregnated air injection mechanism 42 is provided that jets oil-impregnated air toward the blade portions 31 and 32 of the cutter 30. The nozzle 40 of the oil-impregnated air injection mechanism 42 faces the blade portion 31 of the cutter 30. The injection timing of oil-impregnated air is controlled by a limit valve 47, and the oil-impregnated air injection mechanism 42 ejects oil-impregnated air to the blade portion 31 immediately before the start of polishing by the cutter 30, during polishing, and immediately after polishing.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

This invention uses a rotary cutter to polish the electrode tip of a spot welding gun. This invention relates to an electrode polishing device for a spot welding gun.

0002

[Conventional technology]

For example, in automobile manufacturing factories, robots equipped with spot welding guns are used. It is being said. The spot welding gun is equipped with a pair of electrode tips, and the Spot welding is performed by placing the part to be welded on a workpiece such as a steel plate between the I'm trying to do that. Therefore, the tip of the electrode tip must have a specified shape. There is.

0003 The regular shape of the tip portion of the electrode tip is, for example, a semicircular sphere. However, every now and then As a result of repeated use, the tip wears out and gradually becomes flat. For this reason, Periodically, the tip of the electrode tip is polished using a rotary cutter using an electrode polisher. I then polished it and adjusted the shape.

0004

[Problem that the idea aims to solve]

However, in the case of conventional electrode polishing equipment, as the cutter rotates at high speed, the Chips from the electrode tip may adhere to the blade of the cutter and become burned into the blade. If the chips from the electrode tip stick to the cutter blade, the chips and electricity will be removed even when the cutter rotates. The electrode tips come into contact with each other, making it impossible for the blade to polish the electrode tips sufficiently. The function of the cutter will deteriorate significantly.

[0005] For this reason, the cutter itself must be removed from the electrode polishing device and polished several times a month. The work must be carried out. In that case, the cutter has to be replaced frequently, and Not only is it time-consuming to set up the work, but the lifespan of the cutter is also shortened. Ta.

[0006] Therefore, the purpose of this invention is to prevent the chips of the electrode tip from being burnt in the cutter for polishing the electrode tip. You can prevent the cutter from sticking, reduce the frequency of polishing the cutter, and Electrode polishing equipment for spot welding guns that can extend the life of the cutter It is about providing.

[0007]

[Means to solve the problem]

This invention, which was developed to achieve the above purpose, is a spot welding gun electrode tip. an electrode tip that is opposed to the electrode tip and is movable relative to the electrode tip in the axial direction; A rotary cutter for polishing and air containing oil towards the blade of the cutter. The oil-impregnated air injection mechanism is equipped with a nozzle that spouts oil, and the electrode is connected to the cutter. When the chip relatively moves to a predetermined position, oil-impregnated air is ejected from the nozzle. This is an electrode polishing device for a spot welding gun, which is equipped with an injection timing control means.

[0008]

[Effect]

In the electrode polishing device of the present invention, the electrode tip of the welding gun is fixed to the cutter. When the oil-impregnated air reaches the position, the oil-impregnated air is activated by the injection timing control means. Sprayed onto the cutter blade. Oil-containing air is sprayed using a cutter with an electrode tip. It is preferable to carry out the process immediately before the polishing starts. As the cutter rotates, the electric When the tip of the electrode tip is pressed against the cutter, the tip of the electrode tip The part is polished. Even during polishing, oil-impregnated air flows from the nozzle toward the cutter blade. Since the chips from the electrode tip are blown away by the oil-containing air, In addition, the oil in the oil-containing air adheres to the cutter blade, causing chips to burn onto the blade. It is prevented from sticking.

[0009]

【Example】

An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. FIG. 1 shows a spot welding gun 10 that is part of a welding robot. vinegar Pot welding gun 10 includes a pair of electrode tips 11 and 12. electrode tip 11 and 12 are opposed to each other in the axial direction. Each tip of the electrode tips 11 and 12 Each part is semicircular.

0010 Electrode tips 11 and 12 are provided on a frame 13 of a welding robot. Friends The arm 13 can reciprocate within a predetermined stroke range in the directions of arrows A and B in the figure. It has become so. A workpiece such as a metal panel is placed between these electrode tips 11 and 12. Spot welding is performed by applying current to the electrode tips 11 and 12 while sandwiching the welded part. will be done.

[0011] The electrode tips 11 and 12 wear out depending on the number of times they are used, and their tips become flat. It needs to be polished regularly to keep it in shape. The polishing work is called a chip dresser. This is done by an electrode polishing device 15. The welding gun 10 is operated by a driving hand (not shown). It is moved by the stage to the polishing stage where the electrode polishing device 15 is provided. It has become so.

0012 The electrode polishing device 15 includes a base body 20 provided on a floor (not shown). A guide hole 22 along the vertical direction is provided in the bracket 21 provided on the base body 20. I'm being kicked. A column 23 is held in this guide hole 22 so as to be movable in the axial direction. ing. A movable base 25 is provided on the support column 23. Cutter on movable base 25 - A holder 26 and an actuator 27 are provided.

[0013] A cutter 30 is detachably held in the cutter holder 26. cutter 30 Blade portions 31 and 32 are provided on both the front and back sides, respectively. This cutter 30 is Rotated by the actuator 27 via a gear assembly (not shown), etc. It looks like this. The operation of the actuator 27 is controlled by a controller 33. It will be done.

[0014] The movable base 25 has a certain amount of stress against the bracket 21 of the base body 20. It is possible to move up and down within the Roku range. This movable base 25 is It is held floating in a neutral position in the vertical direction by compression coil springs 35 and 36. There is.

[0015] Nozzles 40 and 41 are provided on the movable base 25. The nozzles 40, 41 are It constitutes a part of the oil-impregnated air injection mechanism 42. The above nozzles 40 and 41 are the cutter 3 It faces the direction of the blade parts 31 and 32 of 0. Nozzles 40 and 41 are oil-impregnated air piping 4 Connected to 3.

[0016] The oil-containing air pipe 43 is connected to an air supply pipe 46 via an oiler 45. Ru. The air supply pipe 46 is connected to a discharge port 50 of a limit valve 47. An air pipe 52 is connected to an inlet portion 51 of the limit valve 47. air distribution The tube 52 is connected to a compressed air supply 53.

[0017] The limit valve 47 is provided on the base body 20 side of the electrode polishing device 15. Li A lever-shaped detection section 55 is provided on the mitt valve 47. Detector 55 is on , the limit valve 47 becomes open and compressed air flows into the air supply pipe 4. 6 will be sent.

[0018] The detection unit 55 detects that the electrode tips 11 and 12 of the welding gun 10 are connected to the axis of the cutter 30. By touching a part of the welding gun 10 at the position just before it moves to the line, The limit valve 47 is opened.

[0019] Next, we will discuss the operation of the electrode polishing device 15 equipped with the oil-containing air injection mechanism 42 configured as described above. explain about. The spot welding gun 10 is used to spot metal panels, etc. on a welding line in a factory. Used for cut welding work. Electrode tips 11 and 12 become damaged due to repeated use. Because of wear, the electrode tips 11 and 12 are periodically sent to the electrode polishing device 15 for polishing. Polishing is done.

[0020] The electrode tips 11 and 12 of the welding gun 10 move to the electrode polishing device 15. When the electrode tips 11 and 12 are aligned directly opposite the blades 31 and 32 of the cutter 30, In the previous position, a part of the welding gun 10 may come into contact with the detection part 55 of the limit valve 47. As a result, the limit valve 47 opens and the compressed air from the compressed air supply source 53 is released. The air is sent to the air supply pipe 46 through the limit valve 47.

[0021] When the compressed air passes through the oiler 45, it contains mist-like oil. The air passes through the oil-containing air pipe 43 and is ejected from the nozzle 40 toward the blade portion 31. do. In other words, in this embodiment, the cutter 30 starts polishing the electrode tip 11. Oil-impregnated air is blown onto the blade portion 31 of the cutter 30 before the cutter 30 is cut. In addition, if When the mitt valve 47 is activated, the actuator 27 is activated and the cutter 30 is activated. The rotation begins.

[0022] In the above state, the frame 13 of the welding gun 10 is moved a certain distance in the direction of arrow A in FIG. By moving the electrode tip 11 on the upper side in the figure, one side of the cutter 30 is moved. is pressed against the blade portion 31 of. In this case, depending on the degree of wear of the electrode tip 11, , by appropriately bending the spring 35, the electrode tip 11 is attached to the blade portion 31 of the cutter 30. It is pressed against the electrode tip 11 with a moderate elastic contact force, and the difference in the degree of wear of the electrode tip 11 is also absorbed. It will be done.

[0023] Then, by rotating the cutter 30, the tip of the electrode tip 11 is shaped into a desired shape. After polishing, the frame 13 of the welding gun 10 rises to remove the electrode chip. The pull 11 separates from the blade portion 31 of the cutter 30. At that time, the electrode tip 11 is damaged. The oil-impregnated air is blown by the nozzle 40 for a while after leaving the blade part 31 of the filter 30. Continue attaching.

[0024] As shown in FIG. 2, when the frame 13 of the welding gun 10 is raised, the The electrode tip 12 is pressed against the lower blade portion 32 in the axial direction. In this case too, Before the electrode tip 12 comes into contact with the blade portion 32 of the cutter 30, the oil-impregnated air flows through the nozzle. The liquid is ejected from the pipe 41 toward the blade portion 32.

[0025] Then, the spring 36 is appropriately bent depending on the degree of wear of the electrode tip 12, so that The electrode tip 12 is pressed against the blade part 32 of the cutter 30 with an appropriate pressing force, and rotated. The electrode tip 12 on the lower side of the figure is also shaped into a predetermined shape by the blade portion 32 of the cutter 30. Polished.

[0026] After polishing, the frame 13 of the welding gun 10 is lowered a certain distance, The electrode tip 12 separates from the blade portion 32 of the cutter 30. At that time, electrode tip 1 2 is separated from the blade portion 32 of the cutter 30, the oil-impregnated air is not blown. forced to continue.

[0027] In this way, the oil-impregnated air is sprayed onto the blade parts 31 and 32 of the cutter 30, Do this immediately before polishing with the cutter 30, during polishing, and for a short time after polishing. Therefore, when the electrode tips 11 and 12 are polished by the cutter 30, the Cutting chips from the electrode tips 11 and 12 that are stuck on the blades 31 and 32 of the cutter 30 are prevented from burning. can be avoided.

[0028] For this reason, polishing of the cutter 30 itself, which was previously required several times a month, is now possible. This makes it possible to significantly reduce the number of operations performed, and therefore the cutter 30 can be replaced with a polishing device. It is also possible to reduce the frequency of attachment and detachment. Also, the lifespan of the cutter 30 is We were able to extend it significantly compared to the past.

[0029]

[Effect of the idea]

According to the present invention, chips from the electrode tip are not burned into the cutter for polishing the electrode tip. This reduces the frequency of polishing the cutter, and can extend the lifespan of

[Brief explanation of drawings]

FIG. 1 is a partially sectional side view showing an electrode polishing device and a welding robot according to an embodiment of the present invention.

FIG. 2 is a side view, partially in section, showing an example of the operating mode of the electrode polishing apparatus shown in FIG. 1;

[Explanation of symbols]

10... Spot welding gun, 11, 12... Electrode tip, 1
5... Electrode polishing device, 30... Cutter, 31, 32... Blade portion, 40, 41... Nozzle, 42... Oil-impregnated air injection mechanism,
47...Limit valve (injection timing control means).

Claims (1)

[Scope of utility model registration request] 1. A rotary cutter for polishing an electrode tip, which is opposed to an electrode tip of a spot welding gun and is movable relative to the electrode tip in an axial direction; The oil-impregnated air injection mechanism includes a nozzle that ejects air, and an injection timing control means that ejects oil-impregnated air from the nozzle when the electrode tip moves relative to the cutter to a predetermined position. Electrode polishing device for spot welding guns.