JPH0469032B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a welding machine for resistance welding methods (hereinafter simply referred to as welding) such as spot welding, projection welding, and fusing welding, to prevent electrode roughness, foreign matter adhering to the electrode, etc. The present invention relates to an automatic electrode exchange device that automatically replaces old electrodes with new electrodes one by one in response to wear and tear.

Conventionally, the welding machine was stopped each time the electrodes were worn out and the electrodes were replaced manually. but,
There is the inconvenience that it is not automatic, and there is also the problem that the welding machine must be stopped frequently, resulting in a low operating rate.

The electrode device for a welding machine disclosed in Utility Model Publication No. 43-22281 has electrode set screws 25 ₁ , 25 ₂ , 25 attached to a head 21 which is rotatably attached to a fixed shaft 22 and fixed by a rotation set screw 23 . ₃ , the rear end is removably attached, and the head 21 at the tip protrudes radially from the side surface.It is merely an electrode device comprising welding rod electrodes 24 ₁ , 24 ₂ , 24 ₃ . . . having different shapes, and the electrodes 24 ₁ , 24 ₂ , 24 ₃ ..., with the welding machine stopped, loosen the rotation set screw 23 by hand, and remove the disc-shaped head 21.
The electrodes 24 ₁ , 24 ₂ , 24 ₃ . . . are rotated by hand around the fixed shaft 23 to select the electrodes 24 1 , 24 2 , 24 3 . The disadvantage is that it cannot be replaced automatically. Further, the electrodes 24 ₁ , 24
₂ , 24 ₃ . . . protrude radially from the fixed shaft 22, so the area around the electrode is large, and the fixed shaft 22 is weak against the bending moment of the welding reaction force. Further, in the welder electrode described in Japanese Utility Model Publication No. 44-21467, a movable block 12 is attached to a fixed block 3 fixed to the electrode rod 1 via a spindle 9 by a clamp nut 11.
It is simply a welder electrode with a plurality of electrodes 14 fixed in the radial direction to a movable block 12, which is rotatably held around an axis perpendicular to the welding machine. Loosen the nut 11 by hand, rotate the movable block 12 by hand around the axis of the spindle 9 to select a new electrode or an electrode made of a different metal, and then tighten the clamp nut 1.
1 is tightened by hand, which has the disadvantage that worn electrodes cannot be replaced automatically. Furthermore, since the unit electrodes 14 protrude in the radial direction at right angles to the axis of the electrode rod 1, the area around the electrodes is large, and the electrode rods 1 are weak against the bending moment of the welding reaction force. Jitsugan Showa 56-
The welding device described in the micro film of No. 127444 (Utility Model Application Publication No. 57-116386) uses a plurality of electrode rods 17.
are arranged radially around the lower electrode part 18, and when the lower electrode part 18 descends and the electrode rod 17 separates from the upper electrode plate 12, the lower electrode part 18 is intermittently rotated, so that the electrode rod 17 can be continuously used. This is merely a means of stopping use to avoid deterioration in life due to overheating and allowing continuous processing to proceed smoothly. To replace the electrode rod 17, the welding machine must be stopped and a new electrode rod 17 must be inserted into the lower electrode section 18. This method has the disadvantage that it must be replaced manually and worn electrodes cannot be replaced automatically. Further, since the electrode rod 17 protrudes in the radial direction of the pivot shaft 19, the area around the electrode rod is large, and the pivot shaft 19 is weak against the bending moment of the welding reaction force.

The present invention was made in view of the above problems, and in order to improve the operation rate of the welding machine, the present invention provides automatic electrode replacement in a welding machine that can automatically replace the electrode without stopping the welding machine. The purpose is to provide equipment.

According to the present invention, as shown in FIG. 1, the slider 9 is connected to the drive device 11 and can advance and retreat along the guide bar 10, and the slider 9 is provided so as to be insertable and removable in the axial direction of the slider 9. a rotating body 2 positioned by a positioning pin 20;
4, a plurality of electrodes 1 arranged concentrically and parallel to the central axis of rotation on the rotating bodies 2 and 4; and one of the electrodes 1 is worn out and the slider 9 is moved back by the drive device 11. When the rotating bodies 2 and 4 come out of the slider 9 together with the positioning pin 20
An automatic electrode exchange device for a welding machine is provided, comprising: an indexing device 14 that automatically exchanges electrodes by indexing and rotating the electrodes around a rotation center axis.

According to the present invention, since the electrode 1 is arranged parallel to and concentrically with the center axis of rotation of the rotating bodies 2 and 4, the area around the electrode 1 is small and compact, and the axis of the electrode 1 and welding are Since the pressure direction is parallel, it is sufficiently strong against the influence of the bending moment of the rotation center axis due to the reaction force of pressure. Furthermore, in the present invention, when replacing the electrode 1, the positioning pin 20
The indexing device 14 for rotating the rotating bodies 2 and 4 with the electrodes 1 can be small.

Further, when one of the plurality of electrodes 1 is worn out, when the slider 9 is retreated by the drive device 11,
Since the rotating bodies 2 and 4 that have come out of the slider 9 are rotated by the indexing device 14, automatic exchange can be performed so that a new electrode 1 comes into contact with the product 18.

Next, the configuration of the present invention will be described with reference to embodiments shown in the drawings. FIG. 1 is a front sectional view showing the mechanism of the apparatus according to the present invention, FIG. 2 is a left side view taken along the arrow, and FIG. 3 is a right sectional view taken along the arrow--line in FIG.

A plurality of electrodes 1 are inserted into the socket 2 in a concentric circle parallel to the rotation center axis of the socket 2.
Reference numeral 3 denotes a back-up screw screwed into the socket 2, and the protruding length a of the electrode 1 to the left side of the socket 2 can be adjusted. 4 is a holder, and socket 2
are fitted with a taper so that they can be freely inserted and removed, and have a gear 5 on the outer periphery. Further, the holder 4 has a guide rod 6 at the rear that passes through the slider 9, and the holder 4 is pressed against the power feeding ring 7 at the tip of the slider 9 via the guide rod 6 by a spring 8. It is tapered fitted to the power feeding ring 7. Since the socket 2 and the holder 4 and the holder 4 and the power supply ring 7 are fitted in a tapered manner, a large conductor area for electricity supply is obtained, and the specific resistance of the device is low.
These sockets 2, holders 4, and power supply rings 7 are mounted on all sliders 9, and are slid by pressure cylinders 11 using two guide bars 10 of the sliders 9 as guides. On the other hand, 12 is a gear, and the indexing device 1 is assembled to the fixed base 13.
4 is coupled to transmit the indexing torque to the gear 5 on the outer periphery of the holder 4. 15, 16, and 17 are insulating materials. 18 is a product to be welded, 19 is a stopper that comes into contact with the guide rod 6, and 20 is a positioning pin fixed to the power supply ring 7 and inserted into the holder 4.

The above mechanism will be explained in order of operation. When the stopper 9 is advanced to the welding position by the pressure cylinder 11, the electrode 1 is pressed against the product 18 as shown in FIG. 1 through the slider 9, holder 4 and socket 2, and the product 18 is pressurized. Electricity is supplied from the power supply ring 7 to the electrode 1 via the holder 4 and the socket 2.
Current flows to the welding point and welding is completed. The socket 2 and the holder 4, and the holder 4 and the power supply ring 7 are each tapered fitted, and the positioning pin 20 fixed to the power supply ring 7 is inserted into the holder 4, so that the holding force in the rotational direction during welding is reduced. is sufficiently strong. Thereafter, the slider 9 is retreated by the pressurizing cylinder 11 to an original position (not shown) at the retreat end of the cylinder 11, and the guide rod 6 hits the stopper 19 on the way and stops. Through this series of operations, the tapered fit between the holder 4 and the power supply ring 7 is released, the positioning pin 20 fixed to the power supply ring 7 is removed from the holder 4, and the holder 4 becomes rotatable, allowing automatic replacement of the electrode 1. becomes possible. This state is set as the original position, and when welding is to be carried out continuously, the above operation is repeated by moving the slider 9 forward and backward by the pressurizing cylinder 11. Automatic exchange of electrodes
In this original position where the slider 9 is at the backward end,
Automatic exchange is performed by transmitting the indexing torque of the indexing position 14 from the gear 12 to the gear 5, and by rotating the holder 4 and the socket 2, the new electrode 1 is brought to face the product 18. The number of electrodes 1 inserted into socket 2 depends on the takt time of the welding machine,
It can be determined by taking into account the lifespan of the electrode 1, the number of indexes of the indexing device 14, the continuous operation time of the welding machine, etc.

Stop the welding machine only when all the inserted electrodes 1 are worn out, remove the socket 2 containing a plurality of worn electrodes 1 from the holder 4, and replace it with the socket 2 in which a plurality of new electrodes 1 have been prepared. .

As an example of numerical performance, the electrode replacement work by stopping the welding machine, which was conventionally done once every 30 minutes, is reduced to once every 4 hours with the present invention, extending the continuous operation interval of the welding machine by eight times. I was able to do that. Furthermore, the time required for electrode replacement can be reduced from the conventional 5 to 10 minutes to 30 seconds with the present invention.

As described above, since the automatic electrode exchange device according to the present invention has the above configuration, one of the plurality of electrodes
When the slider is retreated to the electrode replacement position by the drive device, the rotating body that comes out of the slider is rotated by the indexing device, so that the electrode is automatically replaced with a new one without stopping the welding machine. This has the excellent effect of significantly improving the operating rate of the welding machine. In addition, the time required to replace each electrode can be significantly shortened by replacing the electrodes as a set according to the present invention, and since the electrodes are arranged in a concentric circle parallel to the rotation axis, the periphery of the electrode can be made smaller. It is compact, the electrode rotation center axis is parallel to the welding pressure direction, there is little bending moment to the rotation center axis due to the reaction force of pressure, and it is sufficiently strong. Furthermore, the positioning pin does not come out when replacing the electrode. Therefore, there are many excellent effects, such as the fact that the indexing device for rotating the rotating body can be small.

[Brief explanation of the drawing]

FIG. 1 is a front sectional view showing the mechanism of the automatic electrode exchange device according to the present invention, FIG. 2 is a left side view taken along the arrow, and FIG. 3 is a right sectional view taken along the arrow--line in FIG. 1... Electrode, 2... Socket, 4... Holder,
6... Guide rod, 7... Power supply ring, 9... Slider, 11... Pressure cylinder, 14... Indexing device, 15, 16, 17... Insulating material, 18... Product, 19... Stopper, 20...Positioning pin.

Claims (1)

[Scope of Claims] 1. A slider connected to a drive device and capable of advancing and retracting along a guide bar; a rotating body that is removably inserted in the axial direction of the slider and positioned by a positioning pin; A rotating body having a plurality of electrodes arranged concentrically and parallel to a central axis of rotation on a body, and one of the electrodes being worn out and coming out of the slider together with the positioning pin when the slider is retreated by a drive device. An automatic electrode exchange device for a welding machine, comprising: an indexing device that indexes and rotates the electrode around a rotation center axis to automatically exchange the electrode. 2. Claim 1, characterized in that a power supply ring is fixed to the tip of the slider via an insulating material, and the rotating body and the electrode are energized via the power supply ring. automatic electrode exchange device for welding machines. 3. The automatic electrode exchange device for a welding machine according to claim 1, wherein the rotating body is provided with a taper so that it can be inserted into and removed from the power supply ring. 4. Claim 1, wherein the rotating body includes a socket that stores a plurality of the electrodes, and a holder into which the socket is fitted in a tapered manner, and the holder is rotated by an indexing device. An automatic electrode exchange device in a welding machine according to any one of Items 3 to 3.