JPH0349832Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field This invention relates to a polishing device that automatically polishes the tip of a welding electrode used in spot welding.

Prior Art In spot welding, a metal plate to be welded is held between a pair of welding electrodes, and a low-voltage, high-current current is passed between the two welding electrodes to melt and weld the metal plates.
By the way, during spot welding, the metal plates to be welded are instantly melted and crimped by the high current flowing from the welding electrode, so the surface of the metal plate is oxidized and forms an oxide film, and this oxide film forms at the tip of the welding electrode. If a large amount of this adheres, it becomes difficult for current to flow, which may result in defective welding. Furthermore, during spot welding, the tip of the welding electrode sometimes wears out, making it impossible to obtain sufficient crimp force, resulting in poor welding.

Therefore, after spot welding has been performed a certain number of times, the spot welding machine periodically polishes the surface of the tip of the welding electrode to remove the oxide film or modify the shape.

Conventionally, welding electrodes were polished at the welding site by using a file or dresser to polish the electrode surface without removing the welding electrode from the spot welding process.

Problems that the invention aims to solve Conventionally, the welding electrodes were polished without removing them from the spot welding machine, which required a polishing device for each spot welding machine, resulting in high equipment costs. Furthermore, there was also the possibility that polishing powder generated during polishing would adhere to the spot welding machine and have an adverse effect.

Means for Solving the Problems This invention consists of a slide base and a movable frame placed on a base so as to be movable back and forth and facing each other, a cam rotatably mounted on the slide base, and a cam mounted on the slide base so as to be rotatable. a plurality of welding electrode holding attachments attached radially to the movable frame side attachment part; a rotating cylinder installed on the base to rotate the cam; and a rotation cylinder installed on the base to move the slide table back and forth. a polishing blade rotatably attached to the slide table side of the movable frame; a motor attached to the movable frame and rotating the polishing blade; and a first cylinder rotating the movable frame back and forth. 2 cylinders, the second cylinder is applied with a force weaker than the first cylinder, and the force is strong and weak.
It is designed to operate by switching between stages.

Function The above-mentioned polishing device holds the welding electrode to be polished in the corresponding welding electrode holding attachment, rotates the cam to oppose the held welding electrode to the polishing blade, and then holds the welding electrode in the first cylinder and the second cylinder. is operated to bring the slide table and movable frame close to each other, bring the welding electrode and polishing blade into contact, and rotate the polishing blade with the motor to polish the surface of the welding electrode.

Further, while the polishing blade is new, the second cylinder is operated with a weak force, and when the polishing blade wears out a certain amount, it is operated with a strong force to keep the polishing ability constant.

Embodiment FIGS. 1 to 3 are drawings showing an embodiment of the present invention. In the figures, reference numeral 1 denotes a base, and a rail 2 is laid on the upper surface along the longitudinal direction. 3 is a slide stand attached to the rail 2 so that it can slide freely,
A rotating shaft 4 stands up in the center and is rotatably supported by bearings 5 and 6. Reference numeral 7 denotes a cam placed on the slide table 3, which is formed into a substantially fan shape, and its corner portion is connected to the upper end of the rotating shaft 4. The cam 7
For example, a mounting portion 7a is formed facing in two different directions, welding electrode holding attachments 8 and 9 are attached radially to the mounting portion 7a, and knockout pins 10 and 1 are attached to the rear of each attachment 8 and 9, respectively.
1 is provided. the two attachments 8;
9 is provided so as to be compatible with two types of welding electrodes having different diameters. Incidentally, as the number of types of welding electrodes increases, a corresponding number of attachments may be provided radially. Reference numeral 12 denotes a rotary cylinder for rotating the rotary shaft 4, which is mounted and fixed on a support arm 13 extending behind the lower part of the slide table 3, and the tip of the piston rod 12a is connected to a link 1 configured in an L shape.
4 to the intermediate portion of the rotating shaft 4. Therefore, when the rotating cylinder 12 expands and contracts,
The rotary shaft 4 is pushed and pulled through the link 14 to rotate, and the cam 7 attached to the rotary shaft 4 is rotated.
The stroke of the rotary cylinder 12 is, for example, when in the shortened state, one attachment 8
is set along the longitudinal direction of the base 1, and the other attachment 9 is set along the longitudinal direction of the base 1 when it is in the extended state. Reference numeral 15 denotes a first cylinder that moves the slide table 3 back and forth, and is attached and fixed to a support plate 16 that is fixed upright on the upper surface of the rear end of the base 1, and the tip of the piston rod 15a is connected to a connection integrally formed on the slide table 3. It is connected to arm 17. Therefore, when the first cylinder 15 expands and contracts, the slide base 3 moves back and forth along the rail 2. Reference numeral 18 denotes an electrode extraction cylinder attached to the upper end of the support plate 16 along the front-rear direction, and its piston rod 18a is arranged opposite to the knockout pin 10 or 11 provided on the cam 7.
By the extension operation, the knockout pin 10 or 11 in the front is pushed in and the welding electrode 24 is pushed out from the attachment 8 or 9. A movable frame 19 is slidably attached to the rail 2 so as to face the slide table 3. 20 is movable frame 1
A polishing blade is rotatably attached to the upper end of the welding electrode 9 so as to face the cam 7, and the polishing surface at the rear end matches the shape of the tip of the welding electrode 24. Reference numeral 21 denotes a motor, such as an air motor, attached to the front surface of the upper end of the movable frame 19, and its output shaft (not shown) is connected to the blade 20. Reference numeral 22 denotes a second cylinder for moving the movable frame 19 back and forth, and is attached along the front-rear direction to a mounting plate 23 fixed upright on the front end of the base 1, and its piston rod 22a is connected to the movable frame 19. Therefore, when the second cylinder 22 expands and contracts, the movable frame 19 moves back and forth along the rail 2.

The second cylinder 22 is configured to be able to extend with a force weaker than that of the first cylinder 15 and can be switched between two stages, strong and weak. When the blade 20 is new, it is extended with a weak force, and when the blade 20 is worn out, it is extended with a weak force. Stretch it with strong force so that the polishing ability becomes constant.

To explain the operation of the above structure, the welding electrode 24 to be polished is removed from the spot welding machine, the rotary cylinder 12 is extended or shortened to rotate the cam 7, and the welding electrode 24 to be polished is removed from the spot welding machine. The corresponding attachment 8 or 9 is made to face the blade 20 along the front-back direction, and the welding electrode 24 is inserted therein. After that, when the start button is pressed, the first cylinder 15 is extended to move the slide table 3 forward, and the second cylinder 22 is also extended to move the movable frame 19 back and keep the welding electrode 24 and blade 20 at a constant position. Contact with pressure. When the slide table 3 moves to the forward end, the motor 21 operates to rotate the blade 20 and polish the tip of the welding electrode 24. After polishing for a certain period of time, a timer stops the operation of the motor 21 to stop the rotation of the blade 20, and then the first cylinder 15 and the second cylinder 22 are shortened to move the slide table 3 backward. At the same time, the movable frame 19 is moved forward to separate the welding electrode 24 and the blade 20, and when the slide table 3 reaches the retreating end, the electrode take-out cylinder 18 expands and contracts once to push the knockout pin 10 or 11 and remove the welding electrode. 24 from attachment 8 or 9. The extruded welding electrode 24 is collected in a collection box installed below.

The above operations are repeated to continuously polish the welding electrode 24.

Effects of the invention This invention can automatically polish the welding electrodes removed from the spot welding machine, so the electrodes can be removed from each spot welding machine, collected in one place, and polished, and many types of welding can be done with one polishing device. Since the electrode can be polished, the equipment can be made smaller, and since the polishing can be done at a location different from the welding site, there is no adverse effect on the welding machine.

In addition, the polishing device moves the slide table that holds the welding electrode and the movable frame that holds the polishing blade toward and away from each other.
The distance between the two can be widened, and welding electrodes with widely different lengths can be polished. Moreover, since the second cylinder is operated with a weaker force than the first cylinder, each time the polishing blade polishes, the second cylinder automatically extends to perform polishing. Furthermore, the second cylinder can be switched between two strong and weak levels, and when the polishing blade is new, it is pressed with a weak force, and when it has worn out to a certain extent, it is pressed with a strong force to keep the polishing ability constant. Stable polishing is possible.

[Brief explanation of drawings]

Figure 1 is a front view of the polishing device according to the present invention, Figure 2 is a front view of the polishing device according to the present invention;
The figure is a plan view, and FIG. 3 is a side view. 1... Base, 3... Slide base, 7... Cam, 8, 9... Attachment, 12... Rotating cylinder, 15... First cylinder, 19... Movable frame, 20... Blade, 21... motor, 2
2...Second cylinder.

Claims (1)

[Scope of utility model registration request] A slide stand and a movable frame placed on a base so as to be movable back and forth and arranged facing each other, a cam rotatably mounted on the slide stand, and radially attached to a mounting portion of the cam on the movable frame side. a plurality of welding electrode holding attachments; a rotating cylinder installed on the base to rotate the cam; a first cylinder installed on the base to move the slide table back and forth; and the slide of the movable frame. It has a polishing blade that is rotatably attached to the table side, a motor that is attached to the movable frame and rotates the polishing blade, and a second cylinder that moves the movable frame back and forth. An automatic polishing device for welding electrodes, characterized in that the device operates with a force weaker than that of the first cylinder and is switched between strong and weak in two stages.