JPS6031031Y2 - spot welding equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a spot welding device applied to, for example, after-hem spot welding, and particularly to a spot welding device with a simplified operating mechanism.

For example, when welding the edges of an automobile panel, the edges of the panel are bent in advance by hemming.
It is well known that after hem spot welding is performed by inserting a welding tip into the operating space of a hemming die for bending from the side of the die.

Such after hem spot welding equipment involves moving a welding tip into a small space of a hemming machine installed at a welded part of a workpiece such as a panel in a welding pressurizing direction and inserting and ejecting the welding tip orthogonally thereto. is required.

Conventionally, such a spot welding apparatus is provided with a plurality of driving cylinder devices and the like for operating the welding tip in two directions: workpiece processing and a direction perpendicular to the workpiece processing.

The operation of inserting and ejecting the welding tip into the welding part of the workpiece and the movement operation of applying pressure for spot welding and moving in the opposite direction of pressurization are performed separately by each cylinder device.

For this reason, in conventional spot welding equipment of this type, the control device for centering and perpendicularity of the welding tip is extremely complex, and the operating range is wide, so the secondary cable, air hose, etc. The structure of incorporating cooling water hoses, etc., was also complicated.

Therefore, conventional devices require sophisticated assembly techniques and a large number of man-hours, and have various problems in manufacturing, installation, operation, etc.

The present invention was devised to solve these conventional problems, and by using a rotating link mechanism, only a small number of cylinder devices can be used, simplifying the configuration and facilitating assembly technology. The purpose of the present invention is to provide a spot welding device that can reduce the number of processes and the number of man-hours.

In order to achieve such an objective, the configuration of the present invention is such that the approximately middle portion of the tip base is supported via a pivot so that it can swing freely in the direction of pressurizing the welding tip, and the tip base itself can be rotated in the direction of inserting and ejecting the tip. a retract arm, a retract spring that biases the retract arm in the direction of inserting the tip into the workpiece, a positioning stopper that stops at a predetermined welding position, and a retract arm and the tip base that bias the retract arm in the direction opposite to the direction of pressurizing the welding tip. A locking body that locks each other in a rigid state at a predetermined oscillation position, and a locking body that is connected to the opposite end of the tip base to drive the welding tip in the welding part of the tip base and in the direction of applying pressure. The cylinder device is equipped with a cylinder device.

A link mechanism having such a spring and a stopper, and a single cylinder device enable the welding tip to perform two-way movement in relation to the welding part of the workpiece through the tip base, thereby driving the welding tip. In addition to reducing the number of cylinder devices used as means, the structure for performing certain regulating operations is simplified, making it easier to center and verticalize the welding tip and to assemble various accessories such as secondary cables and air hoses. It is designed to reduce the number of man-hours required for assembly.

Hereinafter, specific embodiments of the configuration of the present invention will be described in detail with reference to the drawings.

Note that the spot welding device according to this embodiment is of a parallel tip type, that is, a type in which a plurality of welding tips are arranged side by side on a workpiece.

Therefore, unlike a spot welding device in which an upper electrode and a lower electrode are sandwiched between a workpiece and a spot welding device in which a cable is connected only to a welding tip placed above a workpiece support, this type has upper and lower electrodes. Of course, it can be applied to spot welding equipment.

In the figure, 1 is a welding device main body, 2 is a gun body that is insulatedly attached to the welding device main body 1, and 3 is a workpiece support that is attached to the gun body 2 so that its vertical position can be adjusted.

An end portion of a workpiece 4 such as an automobile panel is placed on the surface of this workpiece support stand 3.

Although not shown, a hemming die for bending and forming the ends of the workpieces to be welded in advance is disposed above the workpiece support stand 3 so as to be movable up and down.

This hemming die moves up and down with a constant up-and-down stroke, and it is impossible to provide a large space above the workpiece support 3 even when it is going up.

That is, only a relatively small space is provided above the workpiece support base 3, and the welding tip of the spot welding device cannot move significantly in the direction of applying pressure to the workpiece, that is, in the vertical direction.

Therefore, the welding tip 5 is moved via the tip base 6 in the direction in which pressure is applied to the welded portion of the workpiece 4 and in the direction in which the tip is inserted into and removed from the welded portion (horizontal direction in the figure) substantially perpendicular to this direction.

The driving means for moving the chip base 6 is roughly divided into a link mechanism section 7 and a cylinder section 8.

First, the link mechanism portion 7 will be explained.

A current supply cable 9 is connected to a tip base 6 having a welding tip 5 attached to one end.

A base arm 11 is integrally attached to the lower surface of this chip base 6 with an insulating plate 10 interposed therebetween.

In addition, when we refer to the chip base below, we refer to base arm 1.
1 shall be included.

A bracket 12 is provided protrudingly from the lower surface of the tip base 6 at approximately the middle thereof, and the bracket 12 is attached to the retract arm 13 via a pivot 14 in a direction in which the welding tip 5 presses the welded part of the workpiece 4 (up and down direction in the figure). I support it freely.

This retract arm 13 is itself rotatably supported by the gun body 2 via a rotation shaft 14A in a direction in which the welding tip 5 is inserted into and removed from the side of the workpiece 4.

That is, the tip base 6 is rotatably supported by the gun body 2 via the retract arm 13 in a direction in which the welding tip 5 is inserted into and ejected from the side of the welded part of the workpiece 4, and at the same time, the tip base 6 is The welding tip 5 is swingable with respect to the retract arm 13 via a pivot 14 in directions for pressing and separating the welded portion of the workpiece 4 .

This retract arm 13 is biased by a retract spring 15 on the gun body 2 in the direction of inserting the chip into the workpiece 4 .

Then, it is stopped at a predetermined welding position on a wall surface as a vertical stopper 16 provided on the gun body 2.

In other words, the retract arm 13 is in a substantially vertical state, contacts the stopper 16 at a position where the welding tip 5 matches the welded part of the workpiece 4, and is restricted from rotating further in the tip insertion direction. ing.

Further, the retract arm 13 and the tip base 6 are fixed to each other in a rigid state by a locking body 17 at a predetermined swing position of the welding tip 5 in the anti-pressurizing direction.

That is, this locking body 17 is made of a bolt that is located on the side opposite to the workpiece from the pivot shaft 14 of the retract arm 13 and is screwed upward. It's coming.

By adjusting the height at which the bolt serving as the locking body 17 is screwed into the tract arm 13, the position at which the base arm 11 locks on the tip of the locking body 17 can be adjusted.

This locking body 17 comes into contact with the lower surface of the base arm 11 of the tip base 6 when the tip base 6 rotates clockwise in the figure, that is, so that the welding tip 5 moves upward away from the welded part of the workpiece 4. , rotation beyond a certain level is prevented, that is, it is locked in a rigid state.

A cylinder device 18 as the cylinder portion 8 described above is connected to the opposite end of the tip base 6 to the workpiece.

This cylinder device 18 is connected to the cylinder portion 18 via a shaft 19.
A is pivotally attached to the gun body 2, and the tip of the cylinder rod 1BB is rotatably connected to the tip base 6 by another shaft 20.

Therefore, this cylinder device 18 itself can perform substantially the same rotational movement as the retract arm 13 with respect to the gun body 2.

Further, the chip base 6 can also be rotated about the shaft 20 relative to each other.

According to such a configuration, for example, after the welding tip 5 is introduced from the side into the welding part of the workpiece 4 by moving the cylinder rod 18B of the cylinder device 18 in the protruding direction (upward), the welding tip 5 is inserted into the welding part of the workpiece 4. It is possible to pressurize the welded part of the

That is, the retract arm 13 is biased by the retract spring 15 so as to constantly pull the welding tip 5 toward the welded portion of the workpiece 4 .

Therefore, when the cylinder rod 18B is moved in the protruding direction, the retract arm 13 is rotated counterclockwise in the figure by the retract spring 15.

In other words, the welding tip 6 is introduced into the welding portion of the workpiece 4 from the side (right side in the figure).

Then, when the cylinder rod 18B is further extended, it is stopped at a predetermined position by the stopper 16, and the tip base 6 is further rotated counterclockwise about the pivot shaft 14 at the tip of the tract arm 13.

That is, the welding tip 5 is pressurized to the welded portion of the workpiece 4 .

In this case, the axis of the rotation shaft 14 of the retract arm 13,
The pressurizing position of the welding tip 5 against the workpiece 4 when the retract arm 13 is stopped is set based on the arrangement of the axis of the pivot 14 and the axis of the welding tip 5 or the stop position of the retract arm 13 by the stopper 16. be able to.

Therefore, by defining the arrangement of these axes in a certain relationship, the centering and perpendicularity of the welding tip 5 can be set in advance.

In this pressurized state of the welding tip 5, the cable 9
By applying a predetermined welding current to the welding tip 5 via the tip base 6, spot welding of a welded portion of the workpiece 4 can be performed, for example, between a plurality of welding tips arranged in parallel.

Further, after welding is completed, the cylinder rod 18B is driven to move back and forth toward the cylinder portion 18A.

Then, a shaft 20 is attached to the tip of this cylinder rod 18B.
The tip base 6 connected through the welding tip 6 rotates clockwise about the pivot 14 (in the direction of upward separation of the welding tip 5 from the workpiece 4).

Then, the rotation of the welding tip 5 in the anti-pressure direction progresses by a predetermined angle, and the locking body 1 provided on the retract arm 13
7, the tip base 6 can no longer rotate with respect to the retract arm 13, and after that, the tip base 6 is in rigid contact with the retract arm 13, and the retract spring 15 is not attached. It rotates clockwise in the figure (in the direction in which the welding tip 5 is ejected from the welded portion of the workpiece 4 laterally) about the rotation axis 14A against the force.

That is, by the movement of the cylinder rod 1BB in the retracting direction, the welding tip 5 first moves in the counter-pressurizing direction, and then, together with the retract arm 13, a continuous rotation movement is performed to eject the workpiece 4 as a whole from the welded part to the side. It is something that is done.

According to the device of this embodiment having the following configuration and operation, although a single cylinder device 18 is used,
The welding tip 5 can be reliably operated in two directions: the pressurizing direction and the insertion/ejection direction of the workpiece 4.

Therefore, vertical alignment and centering of the welding tip 5 can be performed in advance by setting the tract arm 13, the pivot shaft 14, the rotation axis 14A, etc. as the link mechanism part 7, and the above-mentioned two directions can be achieved by using the minimum driving means. Since the rotational movement can be performed, the operating range is narrower compared to conventional cylinder devices that use a plurality of cylinder devices, and attachment of accessory equipment such as secondary cables, air hoses, cooling water hoses, etc. can be easily performed.

Furthermore, the number of man-hours required for manufacturing and assembling these devices can be significantly reduced compared to conventional devices.

Although this is not the gist of the present invention, the work support stand 3 can be tightened and loosened relative to the gun body 2 by bolts 21, and can be moved in the direction of the workpiece 4 by adjustment bolts 22.

As a result, the workpiece support surface of the workpiece support stand 3 can be freely adjusted to match the dot surface checker 23 fixedly attached to the gun body 2, that is, to a position that supports the workpiece 4 at a predetermined welding height. I can do it.

In addition, according to the apparatus of the present invention, the structure of the entire apparatus can be simplified, and therefore, the welding conditions are also suitable for a case where the capacity is lighter than that which is commonly used in the past.

In other words, the conventional welding current of 8000
A~9000A, welding current 700 for 9~120 kg at 100 welding force, 8 cycles to 12 cycles for energization time.
It is possible to implement QA to 800QA, pressurizing force of 40 to 60 to 9, and energization time of 7 to 8 cycles.

If the diameter of the electrode tip is made smaller by the amount that the current, pressurizing force, energization time, etc. are reduced, and the current density is made to correspond to approximately the same, a spot with approximately the same conditions as conventional large-capacity welding equipment can be obtained. Welding is possible, and a cooling water supply device can be omitted.

As described in detail in the above embodiments, according to the present invention, complex insertion and ejection of welding tips, welding pressurization operations, etc. can be realized using a small number of cylinder devices using a link mechanism.
Centering and perpendicularity of the electrode can be easily performed, and at the same time, the assembly technique for accessory equipment is also simplified, reducing man-hours, making it possible to create a reliable spot welding device with such a simple equipment configuration. can now be carried out, and the initial purpose can be distantly related.

[Brief explanation of drawings]

The figure is a side view showing an embodiment of the present invention. 4... Workpiece, 5... Welding tip, 6
......Tip base, 13...Retract arm, 14...Pivot, 15...Retract spring, 16...Stopper, 18
・・・・・・Cylinder device.

Claims (1)

[Scope of utility model registration request] In the spot welding device, the tip base on which the welding tip is attached is moved by a driving means in a direction in which the welding tip applies pressure to a welding part of a workpiece and in a direction substantially perpendicular to this in a direction in which the tip is inserted into and removed from the welding part. The driving means is
A tract arm that supports a substantially middle portion of the tip base via a pivot so as to be swingable in the direction of pressurizing the welding tip, and is itself rotatable in the direction of inserting and ejecting the tip;
A retract spring that urges the retract arm in the direction of inserting and ejecting the tip into the workpiece, a positioning stopper that stops at a predetermined welding position, and a positioning stopper that moves the retract arm and the tip base to a predetermined oscillation position in the opposite direction of pressurizing the welding tip. a locking body that locks each other in a rigid state, and a cylinder device that is connected to the opposite end of the tip base and drives the welding tip in the welding part of the tip base in the direction of insertion and removal and in the pressurizing direction. A spot welding device comprising: