JP3407105B2 - Projection welding method for perforated parts - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention belongs to the field of projection welding a perforated part to a steel plate part, and is particularly useful in the case of a projection nut.

[0002]

2. Description of the Related Art A conventional method of welding a perforated part such as a projection nut to a steel plate part is to mount the steel plate part on an electrode with a guide pin, and at this time, prepare a pilot hole for the steel plate part. Insert the guide pin through the guide pin and fit the projection nut onto the guide pin. After that, the opposing electrodes are advanced to energize. The guide pin described above fulfills the function of positioning the nut, but does not fulfill the function of centering in relation to the guide pin of the counterpart electrode protruding from the nut. The opposing electrodes of the other party include a type without a guide pin and a type with a guide pin installed. Even the type having the guide pin does not perform the centering function in relation to the guide pin of the other electrode.

[0003]

[Means for Solving the Problem and Its Action] This invention is
The present invention is provided to solve the above-mentioned problems. In the invention of claim 1, in which a perforated part is welded to a steel plate part between both electrodes, a receiving hole and a taper are formed in a receiving guide pin of one electrode. Part is formed and the receiving guide pin
Emissions is configured to penetrate the lower hole of the steel sheet part, an insertion part provided which enters into the receiving hole in the entry guide pins of the other electrode, the entry guide pin penetrates the tapered hole part apertured The holding guide pin is configured to hold the perforated component, and the elasticity of the receiving guide pin is set to be stronger than the elasticity of the entry guide pin to project. After passing through the other electrode, the other electrode advances and the insertion part of the entry guide pin enters the receiving hole, and at the same time as this, the tapered part of the receiving guide pin matches the tapered hole of the perforated part, and the other electrode first entry guide pin and the other conductive when but advanced to
Pushed relatively to the in-electrode, then, pushed into the receiving guide pins also in one of the electrodes, one electrode and the steel sheet part, the steel sheet part and perforated parts are brought into close contact with a perforated part and the other electrode In the projection welding method for a perforated part, a welding current is applied in this state. Therefore, the entry guide pin advances to the place where the receiving guide pin penetrates the lower hole of the steel plate part, and the insertion part enters into the receiving hole, and at the same time as this, the tapered part of the receiving guide pin becomes When the electrode matches the taper hole and the other electrode advances, the entry guide pin is first pushed relatively into the electrode, and then the receiving guide pin is also pushed into the electrode, so that one electrode and the steel plate are pushed. The component, the steel plate component and the perforated component, and the perforated component and the other electrode are brought into close contact with each other, and the welding current is supplied in this state.

The invention of claim 2 is characterized in that, in claim 1, the perforated part is a projection nut, and the operation is the same as that described above.

[0005]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below with reference to the illustrated embodiments. As the perforated part to which the present invention is applied, there are various types such as a distance piece and a projection nut. In this embodiment, the projection nut is used. FIG. 5 is a side view schematically showing the entire apparatus, in which an arm 2 is connected to a column 1 firmly fixed to a stationary member, and an air cylinder 3 is attached to the tip thereof. One electrode 5 is attached to a piston rod 4 of the air cylinder 3, and a receiving guide pin 6 is installed at the tip thereof. Similarly, the air cylinder 8 is attached to the tip of the other arm 7, the other electrode 10 is attached to the piston rod 9, and the entry guide pin 11 projects from this electrode. The positional relationship between the electrodes 5 and 10 is set so that the guide pins 6 and 11 are coaxial with each other. As shown in FIGS. 1 and 2, the projection nut 12 has a threaded hole 13 and a tapered hole 14 which are continuous with each other, and a projection 15 for welding. The nut 12 is moved into the guide pin 11 by the nut supply device described later.
And the approach guide pin 11 penetrates the screw hole 13 and the tapered hole 14 to hold the nut 12.

A lower hole 17 through which the receiving guide pin 6 penetrates is formed in the steel plate component 16, and the steel plate component 16 is firmly gripped by the chuck 19 of the robot device 18.

Description will be given with reference to FIGS. 1 and 2. One electrode 5 has a cylindrical shape, and two members are integrated by a screw portion 20, and a cylinder 21 is formed inside. The receiving guide pin 6 is inserted so that it can slide in the through hole 22. The piston 23 is slidably inserted into the cylinder 21, and the receiving guide pin 6 is firmly connected to the piston 23. For this connection, a bolt 24 is provided integrally with the receiving guide pin 6, and a fixing nut 25 is fastened thereto. The coil spring 26 accommodated in the cylinder 21 provides elasticity for causing the receiving guide pin 6 to project. The coil spring 26 is seated on the insulating plate 27. The piston 23 and the insulating plate 27 are Teflon (registered trademark).
Made of synthetic resin like. The receiving guide pin 6 is made of stainless steel.

A receiving hole 28 is opened in the center of the receiving guide pin 6, and a taper portion 29 is formed on the outer peripheral side of the receiving hole 28. This taper portion 29 is the nut 1
It coincides with the two tapered holes 14.

The other electrode 10 has a cylindrical shape, and two members are integrated by a screw portion 30, and a cylinder 3 is provided inside.
1 is formed. The entry guide pin 11 is inserted so that it can slide in the through hole 32. The piston 33 is slidably inserted into the cylinder 31, and the entry guide pin 11 is firmly connected to the piston 33. For this connection, a bolt 34 is provided integrally with the approach guide pin 11, and a fixing nut 35 is fastened thereto.
The coil spring 36 accommodated in the cylinder 31 imparts an elastic force that causes the approach guide pin 11 to project. The coil spring 36 is seated on the insulating plate 37. The elasticity of the coil spring 36 is set to be weaker than the elasticity of the coil spring 26 of the one electrode 5. Since the coil spring 36 has a weak elasticity, stop the coil spring 36 and press the air hose 4 as shown by the chain double-dashed line.
7 may be opened in the cylinder 31, and the elastic force may be applied to the piston 33 with a weak air pressure. The piston 33 and the insulating plate 37 are made of synthetic resin such as Teflon (registered trademark) . And the approach guide pin 11
Is made of stainless steel.

The entry guide pin 11 has a small diameter insertion portion 38, a large diameter portion 39 that slides in the through hole 32, and a taper shape that connects the insertion portion 38 and the large diameter portion 39 to lock the nut 12. The connecting portion 40 of Further, the insertion portion 38 is set to a thickness that allows the insertion portion 28 to be properly inserted into the receiving hole 28, and in the state where the nut 12 is held, it projects from the nut 12 over a sufficient length as illustrated.

There are various methods for supplying the nut 12 to the entrance guide pin 11, but two examples are shown in FIGS. 3 and 4. The one in Figure 3 is
A concave portion 42 which opens downward is formed at the tip of the supply rod 41, and a magnet 43 for holding the nut 12 received therein is attached to the concave portion 42. Supply rod 41
Is provided with a driving means such as an air cylinder (not shown) so as to perform a square motion like a square arrow 44. When the supply rod 41 descends from the state of FIG. 3 to fit the screw hole 13 of the nut 12 into the entry guide pin 11 and the supply rod 41 retracts to the right from that position, the nut supply ends.

In the case of FIG. 4, the supply rod 45 is of a type that advances and retreats obliquely from above, and has a screw hole 13 of the nut 12.
A thin guide rod 46 that penetrates through is provided. The feed rod 45 advances with the nut 12 skewered, and the tip of the guide rod 46 enters the entry guide pin 11
When stopped immediately before, the nut 12 descends by inertia and is fitted to the approach guide pin 11 to complete the nut supply.

The operation of this embodiment will be described. The steel plate component 16 is stopped by the chuck 19 at the position shown in FIG. First, when one of the electrodes 5 descends, the receiving guide pin 6 enters into the pilot hole 17 and the descending of the electrode 5 stops when the end surface of the electrode 5 comes into close contact with the steel plate component 16. In this state, the taper portion 29 also projects below the steel plate component 16. Next, when the other electrode 10 rises, the insertion portion 38 of the entry guide pin 11 enters the receiving hole 28, and at the same time as this, the tapered portion 29 causes the tapered portion 1 to move.
Match 4 Further, when the electrode 10 rises, the elastic force of the coil spring 26 is stronger than the elastic force of the coil spring 36, so that the approach guide pin 11 is pushed down and the lower end surface of the nut 12 comes into close contact with the upper end surface of the electrode 10. In this state, the protrusion 15 and the lower surface of the steel plate component 16 are not in contact with each other, but when the electrode 10 further rises, the rising force of the electrode 10 is transmitted to the receiving guide pin 6 from the matching portion of the taper. The receiving guide pin 6 is relatively pushed into the electrode 5 while compressing the coil spring 26. As a result, the protrusion 15 is pressed against the lower surface of the steel plate component 16. Here, when a welding current is applied between both electrodes, the projection 15 is welded to the steel plate component 16 and the state shown in FIG. 2 is obtained. From this state, the electrode returns in the reverse order of the above-described operation, and the steel plate component 16 with the nut is sent to the next location by the robot device 18.

When the above-mentioned protrusion 15 is pressed against the lower surface of the steel plate component 16, one electrode 5 and the steel plate component 16, the steel plate component 16 and the nut 12, and the nut 12 and the other electrode 10 are provided.
Each is closely attached. In order to obtain the above-mentioned operation, the air cylinders 3 and 8 must be operated in sequence, but this is achieved by adopting a normal electrically operated air control valve or control circuit. Since it can be easily implemented, detailed description is omitted here.

In the illustrated embodiment, the steel plate component 16
Is supported by the chuck 19, so that the steel plate component 16 has both electrodes advanced while the steel plate component 16 remains stationary.
Where the 6 can be moved, the steel plate part 16 may be moved towards the one stationary electrode 5 to allow the receiving guide pin 6 to pass through the pilot hole 17; The invention described above includes such a case. Further, the nut 12 is in a state of being held by the connecting portion 40 and floating in the air in FIG. 1, but instead of this, as shown by the two-dot chain line in FIG. Holding the end faces in close contact with each other can also be included in another claim. Such a modification has an advantageous effect that the retracting stroke of the approach guide pin 11 is minimized and the operation is simplified.

In the above-described embodiment, the tapered portion 28 is shown to fit into the tapered hole 14 almost at the same time when the insertion portion 38 enters the receiving hole 28. Having a width is also included in the present invention. Specifically, after the insertion portion 38 enters the receiving hole 28, the upper end surface of the other electrode 10 comes into close contact with the lower end surface of the nut 12, and the nut 12 moves while the electrode 10 moves upward. A taper match is made. This is what is stated in the claims as "substantially at the same time".

By adopting a method of supporting the steel plate component 16 so that the steel plate component 16 can be moved along the stroke axis of the electrode, various operating sequences of the electrodes 5, 10 can be selected. That is, when the electrode 10 is stationary and only the electrode 5 is moved, when only the electrode 10 is moved and the electrode 5 is stationary, when both electrodes 5 and 10 are moved as described in the above operation. and so on. The steel plate component 16 is suitably supported by a chuck mechanism attached to the stroke mechanism so that it can follow such various electrode movements. However, in some cases, it is also possible for an operator to manually support the steel plate component to adapt to the movement of the electrode.

In the illustrated embodiment, both electrodes are aligned on the vertical axis, but the axes may be inclined or horizontal, or the embodiment may be turned upside down. It is also possible to However, when changing the direction like this, the approach guide pin 1
It is necessary to embed a magnet in the nut 1 so that the nut 12 does not drop or be displaced. The embedding of such a magnet can also be described as another claim.

[0019]

According to the present invention, the receiving guide pin penetrates the lower hole of the steel plate component to determine the relative position between the receiving guide pin and the steel plate component, and the receiving guide pin is inserted into the receiving hole of the receiving guide pin. The relative position between the perforated part and the steel plate part is fixed by the insertion part entering and the centering of both guide pins being confirmed, and the tapered part of the receiving guide pin matching the taper hole of the perforating part, etc. Therefore, it is possible to remarkably improve the accuracy of the welding position of both parts. In particular, the receiving guide pin penetrates the steel plate part and the insertion part enters the receiving hole, so that the relative positions of both parts and both electrodes are determined, and the cause of positional deviation is completely eliminated. Therefore, it is possible to obtain highly accurate component welding and reliable welding operation.

Since the elastic force in the protruding direction imparted to both guide pins is set to have the above-mentioned strength, the both guide pins are sequentially pushed into the electrodes in order, and FIG. It is possible to reliably reach the final close contact state such as.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional side view showing a main part of an embodiment of the present invention.

FIG. 2 is a partial vertical cross-sectional side view in which a local portion of FIG. 1 is enlarged.

FIG. 3 is a side view showing a method of supplying perforated parts.

FIG. 4 is a side view showing another method for supplying a perforated component.

FIG. 5 is a side view of the entire apparatus.

[Explanation of symbols]

5, 10 electrodes 16 Steel plate parts 12 Perforated parts (projection nut) 6 Acceptance guide pin 28 receiving hole 29 Tapered part 17 pilot hole 11 Approach guide pin 38 Insert 14 Taper hole 26 coil spring 36 coil spring

Claims (2)

(57) [Claims] 1. A one welding the perforated parts in the steel sheet part between both the electrodes, have been receiving hole and the tapered portion receiving the guide pin of one of the electrodes is formed, the acceptance Gaidopi
Emissions is configured to penetrate the lower hole of the steel sheet part, an insertion part provided which enters into the receiving hole in the entry guide pins of the other electrode, the entry guide pin penetrates the tapered hole part apertured The holding guide pin is configured to hold the perforated component, and the elasticity of the receiving guide pin is set to be stronger than the elasticity of the entry guide pin to project. After passing through the other electrode, the other electrode advances and the insertion part of the entry guide pin enters the receiving hole, and at the same time as this, the tapered part of the receiving guide pin matches the tapered hole of the perforated part, and the other electrode first entry guide pin and the other conductive when but advanced to
Pushed relatively to the in-electrode, then, pushed into the receiving guide pins also in one of the electrodes, one electrode and the steel sheet part, the steel sheet part and perforated parts are brought into close contact with a perforated part and the other electrode , A projection welding method for perforated parts, wherein a welding current is applied in this state. 2. The projection welding method for a perforated part according to claim 1, wherein the perforated part is a projection nut.