KR101923667B1 - Electric resistance spot welding machine with double composite electrode tips - Google Patents

Abstract

The present invention relates to an electric resistance spot welder having a double composite electrode tip, wherein an electric resistance spot welder having a double composite electrode tip according to the present invention includes a first metal plate and a second metal plate superimposed thereon, The spot welding rod includes a first spot welding support bar in the form of a rod, which is supplied with power from a first power supply unit, and a second spot welding rod A second spot welded support rod in the form of a rod receiving power from a second power supply and receiving the first spot welded support bar so as to be spaced apart from the first spot welded support bar, a first electrode tip coupled to an end of the first spot welded support bar, And a second electrode tip coupled to an end of the welding support rod and receiving the first electrode therein .

Description

TECHNICAL FIELD [0001] The present invention relates to an electric resistance spot welder having a double composite electrode tip,

The present invention relates to an electric resistance spot welder having a double composite electrode tip, and more particularly, to an electric resistance spot welder having a double composite electrode which welds two metal plates by melting a contact surface at a predetermined position between metal plates in a state in which metal plates of different materials are overlapped, To an electric resistance spot welder having an electrode tip.

Electrical resistance spot welding is a technique of melting and welding the contact surfaces of two metal plates by heat generated by contact resistance at the contact surfaces between the metal plates by energizing a large amount of current by using electrodes on a part of two overlapping metal plates. This is a relatively tricky technique in which the welding characteristics such as the size, time, and pressing conditions of the current to be welded must be controlled according to the state of the contact surface.

The use of non-ferrous metals is increasing due to the weight reduction of automobiles, and therefore spot welding between dissimilar metal plates between a conventional steel plate and a lightweight non-ferrous metal plate is required. However, in the case of spot welding by electrical resistance heat in the existing contact surface, it is difficult to spot weld the dissimilar metal plate due to the difference in melting temperature of the dissimilar metal plate to be welded, as compared with the heat generated by the contact resistance.

Korean Patent No. 10-1525018

SUMMARY OF THE INVENTION It is therefore an object of the present invention to solve the above-mentioned problems of the prior art, and it is an object of the present invention to provide an electrode for heating a welding portion by resistance heating of an electrode, A spot electrode having a double composite electrode tip including a tip is used to control the shape of the electrode tip, the amount of current supplied to the electrode tip, or the shape of the electrode tip according to the type and thickness of the dissimilar metal plate to enable spot welding of the dissimilar metal plate And an electric resistance spot welder having a double composite electrode tip.

The problems to be solved by the present invention are not limited to the above-mentioned problems, and other matters not mentioned can be clearly understood by those skilled in the art from the following description.

According to the present invention, there is provided an electric resistance spot detecting method comprising the steps of: placing a first metal plate material and a second metal plate material overlapping each other in a space therebetween and having a spot electrode having an electrode formed at one end thereof in contact with the metal plate material; In the welding machine, the spot electrode includes a first spot welding support bar in the form of a bar supplied with power from the first power supply unit; A second spot welding support bar in the form of a rod receiving power from a second power supply and receiving the first spot welding support bar so as to be spaced apart from the first spot welding support bar; A first electrode tip coupled to an end of the first spot weld support bar; And a second electrode tip coupled to an end of the second spot weld support bar and receiving the first electrode therein.

Here, the first spot welding support bar and the second spot welding support bar may each be formed of a cylindrical bar, and the first spot welding support bar may be disposed concentrically within the second spot welding support bar.

The first electrode tip may be formed with an indentation groove at an end thereof so that the groove of the indentation may be extrapolated to an end of the first spot welding support rod so that the first electrode tip may be coupled to the first spot welding support rod .

Here, a first inclined surface is formed on the outer surface of the end portion of the first spot welding support rod, and a second inclined surface corresponding to the first inclined surface is formed on the inner surface of the recessed groove of the first electrode tip, .

Here, the end of the second electrode tip may be inserted into the inner surface of the end portion of the second spot welding support rod, and the second electrode tip may be coupled to the second spot welding support rod.

A fourth inclined surface corresponding to the third inclined surface may be formed on an end surface of the end portion of the second electrode tip so as to be inserted and coupled to the inner surface of the end portion of the second spot welding support rod.

A circular rod having a circular protruding section is formed in the lower part of the first electrode tip, and one end face of the circular rod of the first electrode tip is exposed under the second electrode tip, A hole through which the rod is inserted can be formed.

Here, when the first spot welding electrode and the second spot welding electrode, which are disposed opposite to both sides of the overlapped metal plate, contact both surfaces of the metal plate, the first spot welding of the first power supply unit, A first electrode tip of the first spot-welding electrode, a first spot-welding support bar of the second spot-welding electrode, and a first waste-welding support rod of the first spot- A second electrode tip of the first spot welding electrode, a second electrode tip of the second spot welding electrode, a second spot welding electrode of the first spot welding electrode, And a second waste electrical circuit connected to the second power supply unit in order.

Here, the first spot welding support rod may further include a cooling water inlet tube into which a sealed cooling water space for injecting cooling water is inserted, and a coolant injection pipe inserted into the cooling water space to inject cooling water.

Here, one end surface of the first electrode tip and one end surface of the second electrode tip can simultaneously contact the metal plate.

Here, the second electrode tip is formed of a material having a high resistance value, and when the current flows through the second power supply unit, resistance heat is generated to heat the metal plate.

Here, the strength of the power supplied from the first power supply unit and the second power supply unit, the material of the first electrode tip and the second electrode tip, or the material of the first electrode tip and the second electrode tip, It is possible to perform spot welding with respect to different types of metal plate by changing at least one of the contact area and the contact area.

According to the present invention, the above object can also be achieved by a plasma processing apparatus comprising a spot electrode having a first metal plate and a second metal plate superimposed thereon and having an electrode formed at one end thereof in contact with the metal plate, In the resistance spot welding machine, the spot electrode includes a rod-shaped spot welding support rod supplied with power from a power supply unit; A first electrode tip coupled to an end of the spot weld support bar; And a second electrode tip coupled to an end of the spot weld support bar and receiving the first electrode tip therein.

Here, the spot welding support bar may have an annular groove formed at an end of the spot welding support rod, and the first electrode tip and the second electrode tip may be coupled to the annular groove.

The first electrode tip is formed with an engraved groove at an end thereof and the groove of the engraved first electrode tip is extrapolated to an inner side face of the annular groove so that the first electrode tip is coupled to the spot welding support rod .

Here, the end of the second electrode tip may be inserted into the outer side surface of the annular groove, and the second electrode tip may be coupled to the spot welding support rod.

According to the present invention, the above object can also be achieved by a plasma processing apparatus comprising a spot electrode having a first metal plate and a second metal plate superimposed thereon and having an electrode formed at one end thereof in contact with the metal plate, In the resistance spot welding machine, the spot electrode includes a rod-shaped spot welding support rod supplied with power from a power supply unit; A connection portion coupled to the spot welding support bar; A first electrode tip coupled to an end of the spot weld support bar; And a second electrode tip coupled to an end of the connection and receiving the first electrode tip therein.

The connection portion is formed with a hollow and is coupled to an outer circumferential surface of the spot welding support rod and extends to surround and surround the end portion of the end portion of the spot welding support rod to form an annular groove at an end of the spot welding support rod and the connection portion, And the first electrode tip and the second electrode tip may be coupled to the annular groove.

In this case, a side slope is formed on the outer circumferential surface of the spot welding support bar, and an inner slope corresponding to the side slope is formed in the hollow inner side of the connection portion where the hollow is inserted to be inserted into the spot welding support rod, Can be inserted and bonded.

The first electrode tip is formed with an engraved groove at an end thereof and the groove of the engraved first electrode tip is extrapolated to an inner side face of the annular groove so that the first electrode tip is coupled to the spot welding support rod .

Here, the end of the second electrode tip may be inserted into the outer side surface of the annular groove, and the second electrode tip may be coupled to the connection portion.

A circular rod having a circular protruding section is formed in the lower part of the first electrode tip, and one end face of the circular rod of the first electrode tip is exposed under the second electrode tip, A hole through which the rod is inserted can be formed.

Here, a first inclined surface is formed on the inner side surface of the annular groove, and a second inclined surface corresponding to the first inclined surface is formed on the inner side surface of the depressed portion of the first electrode tip.

Here, a third inclined surface is formed on the outer side surface in the annular groove, and a fourth inclined surface corresponding to the third inclined surface is formed on the outer surface of the end of the second electrode tip.

In this case, the spot welding support rod may further include a cooling water inlet tube into which a sealed cooling water space for injecting cooling water is inserted, and a cooling water injection pipe inserted into the cooling water space to inject cooling water.

Here, one end surface of the first electrode tip and one end surface of the second electrode tip can simultaneously contact the metal plate.

Here, the second electrode tip is formed of a material having a high resistance value, and when the current flows through the second power supply unit, resistance heat is generated to heat the metal plate.

According to the electric resistance spot welder having the double composite electrode tip of the present invention as described above, it is possible to perform spot welding with respect to the dissimilar metal plate material.

Further, the amount of current supplied to each electrode tip constituting the double composite electrode tip is controlled to be different from each other, and the spot weldability of the dissimilar metal plate material is controlled in accordance with the difference in amount of current supplied to each electrode tip, There is an advantage that the spot welding can be easily performed.

Further, since the double composite electrode tip can be easily replaced, the spot weldability of the dissimilar metal plate can be controlled by changing the material constituting the double composite electrode tip or adjusting the contact area with the metal plate according to the shape of the electrode, There is an advantage that spot welding can be easily performed with respect to the welding wire.

1 is a cross-sectional view showing a spot electrode of an electric resistance spot welder having a double composite electrode tip according to an embodiment of the present invention, disposed on both sides of a metal plate.
Fig. 2 is a partially cutaway perspective view of the double spot welding support bar of Fig. 1;
3 is a partially cutaway perspective view of the first electrode tip of FIG.
4 is a partially cutaway perspective view of the second electrode tip of FIG.
5 is a partially cutaway perspective view showing a state where the first electrode tip and the second electrode tip are coupled to the double spot welding support rod.
Fig. 6 is a front view of Fig. 5 showing the contact surface of the double composite electrode tip with the metal plate. Fig.
FIG. 7 is a view showing a flow of a double current when spot welding is performed using an electric resistance spot welder having a double composite electrode tip according to an embodiment of the present invention.
8 is a view illustrating a process of performing welding using an electric resistance spot welder having a double composite electrode tip according to an embodiment of the present invention.
9 is a cross-sectional view of a spot welding rod of an electric resistance spot welder having a double composite electrode tip according to another embodiment of the present invention.
Fig. 10 is a sectional view showing a modification of Fig. 9. Fig.

The details of the embodiments are included in the detailed description and the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention, and the manner of achieving them, will be apparent from and elucidated with reference to the embodiments described hereinafter in conjunction with the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. To fully disclose the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims. Like reference numerals refer to like elements throughout the specification.

Hereinafter, the present invention will be described with reference to the drawings for explaining an electric resistance spot welder having a double composite electrode tip according to embodiments of the present invention.

FIG. 1 is a cross-sectional view showing a spot electrode of an electric resistance spot welder having a double composite electrode tip according to an embodiment of the present invention disposed on both sides of a metal plate, FIG. 2 is a cross- 1 is a partial cutaway perspective view of the first electrode tip of FIG. 1, FIG. 4 is a partially cutaway perspective view of the second electrode tip of FIG. 1, FIG. 5 is a partial cutaway perspective view of the first electrode tip of FIG. FIG. 6 is a front view of FIG. 5 showing a contact surface of a double composite electrode tip with a metal plate, FIG. 7 is a cross-sectional view of a double- Fig. 5 is a diagram showing the flow of a double current when spot welding is performed using an electric resistance spot welder having a composite electrode tip. Fig.

The spot welding rod 100 of the electric resistance spot welder having the double composite electrode tip according to an embodiment of the present invention includes a first spot welding support rod 110, a second spot welding support rod 120, a first electrode tip 130, And a second electrode tip (140).

The first spot weld support bar 110 forms a double spot weld support bar together with the second spot weld support bar 120. The first spot weld support bar 110 receives a power from an external first power supply unit in the form of a rod, So that current flows through the first electrode tip 130 coupled to one end of the first electrode tip 110. Preferably, the first spot weld support bar 110 may be formed of a cylindrical bar, but is not limited thereto.

The first spot welding support rod 110 is formed with a closed cooling water space 112 into which cooling water is injected and is connected to the cooling water space 112 and the first spot welding A cooling water injection pipe 114 connecting the outside of the support rod 110 may be formed.

The second spot welding support rod 120 is supplied with power from an external second power supply unit in the form of a rod and is electrically connected to a second electrode tip 140 coupled to one end of the second spot welding support rod 120 .

1 and 2, the second spot weld support bar 120 receives the first spot weld support bar 110 therein so as to be spaced apart from the first spot weld support bar 110, The two spot welding support rods 120 are characterized in that the double spot welding support rods are formed so as not to contact each other. Therefore, the magnitude of the power supplied to the first spot welding support bar 110 through the first power supply unit and the magnitude of the power supplied to the second spot welding support bar 120 through the second power supply unit can be controlled to be different from each other . When the first spot welding support bar 110 is formed as a cylindrical bar, the second spot welding support bar 120 is also preferably formed of a concentric circular cylindrical bar.

The first electrode tip 130 is coupled to one end of the first spot weld support bar 110 and contacts the metal plate 200 during spot welding. 3, the upper portion of the first electrode tip 130 is formed into a cylindrical shape having a recess 132 formed therein. The recess 132 is formed at the lower end of the first spot welding support rod 110, So that the first electrode tip 130 can be coupled to the first spot welding support bar 110.

At this time, as shown in the drawing, the outer surface of the lower end portion of the first spot welding support rod 110 is formed with the inclined surface 111 so that the diameter of the cylindrical body is reduced downward, An inclined surface 131 is formed on the inner surface of the groove 132 to correspond to the inclined surface 111 so that the first electrode tip 130 can be easily coupled to the first spot welded support bar 110.

A circular rod 134 protruding in a circular shape in section may be formed under the first electrode tip 130. A circular rod 134 is inserted into a hole 144 of a second electrode tip 140 to be described later So that the first electrode tip 130 is brought into contact with the metal plate 200 to conduct electricity.

The second electrode tip 140 is coupled to one end of the second spot weld support bar 120 and contacts the metal plate 200 during spot welding. At this time, the second electrode tip 140 may be formed with a depression 142 corresponding to the shape of the first electrode tip 130 so as to receive the first electrode tip 130 therein. When the first electrode tip 130 is formed in a cylindrical shape, the second electrode tip 140 may be formed in a cylindrical shape having a corresponding depression 142 formed therein.

A hole 144 may be formed in the lower end of the second electrode tip 140 to allow the circular rod 134, which is the lower end of the first electrode tip 130, to be inserted. 6, one end face of the first electrode tip 130 may be exposed to the outside and may be in contact with the metal plate 200. In this case, the exposed first electrode tip contact surface 135 and the second electrode tip contact surface 145, which form the hole 144, are made to coincide with each other, so that when the spot welding is performed, The electrode tip 140 can be brought into contact with the metal plate 200 at the same time.

As shown in the drawing, the upper end of the second electrode tip 140 is inserted into the inner surface of the lower end of the second spot welding support rod 120, so that the second electrode tip 140 is attached to the second spot welding support rod 120 Can be combined.

At this time, the inner surface of the lower end of the second spot welding support rod 120 is formed with the inclined surface 121 so as to increase the diameter of the inner surface toward the bottom, and the outer surface of the upper portion of the second electrode tip 140 has the inclined surface 121 So that the second electrode tip 140 can be easily coupled to the second spot welded support bar 120. As shown in FIG.

Since the first electrode tip 130 is coupled to the first spot welding support rod 110 in an inclined plane and the second electrode tip 140 is coupled to the second spot welding support rod 120 in an inclined plane, , It is easy to replace the electrode tips 130 and 140 in the present invention.

7, by using the overlapped metal plate material 200 and the first spot electrode rod 100a and the second spot electrode rod 100b disposed opposite to the both surfaces thereof, Can be configured. That is, the current through the first spot welding support rod 110a and the first electrode tip 130a of the first spot welding rod 100a connected to the first power supply unit passes through the overlapped metal plate 200, And the first spot welding rod 100a connected to the second power supply unit constitutes a first waste electrical circuit connected to the first power supply source through the first electrode tip 130b and the first spot welding support rod 110b of the first spot welding electrode 100b, The current through the second spot welded support bar 120a and the second electrode tip 140a of the second spot electrode 100b through the overlapped metal plate 200 is again transmitted to the second electrode tip 140b and second The second waste electrical circuit connected to the second power source via the spot welding support rod 120b can be constructed.

Therefore, since different power sources can be supplied from the first power supply unit and the second power supply unit to the inner first spot welding support bar 110 and the outer second spot welding support bar 120 constituting the double spot welding support bar The size of the power supplied to the first electrode tip 130 and the size of the power supplied to the second electrode tip 140 can be controlled differently so that the amount of the current supplied to the electrode tips 130 and 140 It is easy to adjust the spot weldability of the dissimilar metal plates 200a and 200b according to the difference.

At this time, the material of the second electrode tip 140 through which the current flows through the first electrode tip 130 through which the current flows through the first power source and the second power source, and the material of the metal tip 130, (Not shown) so as to supply an appropriate current in accordance with a difference in cross sectional area of the contact surfaces 135 and 145 with the plate member 200. The power supply unit includes a current control unit (not shown) And a power supply.

Hereinafter, the operation of performing the spot welding using the electric resistance spot welder having the above-described double composite electrode tip will be described.

8 is a view illustrating a process of performing welding using an electric resistance spot welder having a double composite electrode tip according to an embodiment of the present invention.

The first metal plate 200a and the second metal plate 200b to be welded in the present invention are preferably formed of dissimilar metal plates 200a and 200b having different metal materials, It is not. That is, the electric resistance spot welder of the present invention may be used for welding a metal plate of the same kind.

The first spot welding rod 100a and the second spot welding rod 100b which are respectively disposed on the upper and lower portions of the overlapped different kinds of metal plates 200a and 200b, The two spot electrode bars 100b are moved so that the double composite electrode tips 130a, 140a, 130b and 140b bonded to the ends of the spot electrode bars 100a and 100b are brought into contact with the metal plate members 200a and 200b (b).

Next, a large amount of power is supplied from the second power supply unit to the second spot welding support rod 120a of the first spot welding rod 100a so that the second electrode tip 140a of the first spot welding rod 100a, So that current flows to the second electrode tip 140b of the second electrode 100b. The second electrode tip 140a of the first spot electrode rod 100a and the second electrode tip 140b of the second spot electrode rod 100b are formed of a material having a high resistance value .

Accordingly, when current flows through the second electrode tips 140a and 140b, the second electrode tips 140a and 140b are heated by resistance heating, and the heat is conducted to heat the metal plates 200a and 200b . More specifically, the resistance heating at the second electrode tip 140a of the first spot electrode rod 100a heats the first metal plate material 200a which is conductive and in contact with the second electrode strip 140a, Resistance heat generation at the electrode tip 140b causes the second metal plate 200b to be heated to be brought into contact with the electrode tip 140b.

Next, a large amount of power is supplied from the first power supply unit to the first spot welding support rod 110a of the first spot welding rod 100a so that the first electrode tip 130a of the first spot welding rod 100a, So that current flows to the first electrode tip 130b of the first electrode 100b. At this time, when a large amount of current flows between the dissimilar metal plates 200a and 200b through the protruded circular rod 134 of the first electrode tips 130a and 130b, the current flows from the contact surfaces of the dissimilar metal plates 200a and 200b The contact surface can be heated by the heat generated by the contact resistance.

At this time, the contact resistance heat generated by the first electrode tips 130a and 130b and the heat conducted from the second electrode tips 140a and 140b act synergistically to melt the contact surfaces between the dissimilar metal plates 200a and 200b, The metal plates 200a and 200b can be spot-welded.

As described above, in the present invention, the magnitude of the current flowing from the second electrode tip 140a of the first spot electrode rod 100a to the second electrode tip 140b of the second spot electrode rod 100b and the magnitude of the current flowing from the first spot electrode rod 100a The size of the current flowing from the first electrode tip 130a to the first electrode tip 130b of the second spot electrode rod 100b can be controlled differently to control the size of the different current, The metal plate members 200a and 200b can be easily spot-welded.

The second electrode tip 140a of the first spot welding rod 100a and the second electrode tip 140b of the second spot welding rod 100b can be made of a metal material having a different resistance value and the first spot electrode The electrode tips 130a, 130b, 140a, and 140b can be made of metal materials having different resistance values at the first electrode tip 130a of the first spot electrode 100a and the first electrode tip 130b of the second spot electrode 100b. 140b can be easily replaced by using the inclined surfaces 111, 121, 131, Accordingly, the material of the electrode tips 130a, 130b, 140a, 140b can be changed, and the different types of metal plates 200a, 200b having different melting temperatures can be easily spot-welded.

In addition, the size of the cross-sectional area of the second electrode tip 140a of the first spot electrode 100a in contact with the metal plate 200a and the size of the second electrode tip 140b of the second spot electrode rod 100b, The size of the cross-sectional area of the first spot electrode 100a in contact with the metal plate 200a and the size of the cross-sectional area of the first spot electrode 100a in contact with the metal plate 200a, In the present invention, the electrode tips 130a, 130b, 140a, and 140b having different shapes can be easily replaced with the inclined surfaces 111, 121, and 121b so that the tip 130b can have different cross- 131, and 141, respectively. Accordingly, the contact areas between the electrode tips 130a, 130b, 140a, 140b and the metal plates 200a, 200b can be changed, and the different types of metal plates 200a, 200b having different melting temperatures can be easily spot welded .

Hereinafter, an electric resistance spot welder having a double composite electrode tip according to another embodiment of the present invention will be described.

FIG. 9 is a cross-sectional view of a spot electrode of an electric resistance spot welder having a double composite electrode tip according to another embodiment of the present invention, and FIG. 10 is a cross-sectional view showing a modification of FIG.

Similar to the above embodiment, in this embodiment, spot welding is performed by two spot welding rods 100a and 100b which are in contact with each other between the overlapped first metal plate 200a and the second metal plate 200b, Each of the spot welding rods 100 includes a rod-shaped spot welding support rod 150 supplied with power from a power supply unit, a first electrode tip 130 and a spot welding support rod 150 coupled to ends of the spot welding support rod 150, And a second electrode tip 140 coupled to an end of the second electrode tip 140.

Hereinafter, the description of the present embodiment will be focused on differences from the above-described embodiments with reference to Figs. 1 to 7.

In the above embodiment, the first electrode tip 130 and the second electrode tip 140 are respectively coupled to the double spot welding support rods composed of the first spot welding support rod 110 and the second spot welding support rod 120 , The first electrode tip 130 and the second electrode tip 140 are coupled to the end of the single spot welding support rod 150 at the same time as shown in FIG. 9 in this embodiment.

The second electrode tip 140 is formed to receive the first electrode tip 130 therein so that the second electrode tip 140 can receive the first electrode tip 130 therein And an annular groove 152 (not shown) is formed at the end of the spot welding support rod 150 so that the first electrode tip 130 and the second electrode tip 140 can be coupled to the single spot welding support rod 150 Can be formed.

The shape of the first electrode tip 130 and the shape and structure of the second electrode tip 140 are the same as those in the previous embodiment and thus the inner side surface 153 in the annular groove formed in the end portion of the spot welding support rod 150, The groove 132 of the first electrode tip 130 is extrapolated to the first electrode tip 130 so that the first electrode tip 130 can be coupled to the end of the spot welding support rod 150. The inclined surface 153 is formed on the inner side surface 153 of the annular groove so that the diameter becomes smaller toward the bottom and the inclined surface 153 is formed on the inner side surface of the depressed groove 132 of the first electrode tip 130 The first electrode tip 130 can be easily coupled to the spot welding support rod 150 by forming the inclined surface 131 so as to correspond thereto.

The second electrode tip 140 is inserted into the spot welding support rod 150 so that the end of the second electrode tip 140 is inserted into the annular groove outer side surface 154 formed at the end of the spot welding support rod 150, Lt; / RTI > The outer surface of the end of the second electrode tip 140 is formed with an inclined surface 154 corresponding to the inclined surface 154. The inclined surface 154 is formed on the outer side surface 154 of the annular groove, The second electrode tip 140 can be easily coupled to the spot welding support rod 150. [

When a large amount of power is supplied from the power supply unit connected to the spot welding support rod 150, a part of the current flowing along the spot welding support rod 150 passes through the second electrode tip 140, The electrode tip 140 generates resistance and the heat is conducted to the metal plate 200 to heat the metal plate 200. The remaining current flowing along the spot welding support rod 150 flows to the contact surface of the dissimilar metal plates 200a and 200b through the first electrode tip 130 to heat the contact surface due to the heat generated by the contact resistance.

In this way, the heat generated by the second electrode tip 140 and the contact resistance generated by the first electrode tip 130 act upward to melt the contact surfaces between the dissimilar metal plates 200a and 200b to form the dissimilar metal plates 200a, 200b can be spot-welded.

Fig. 10 shows a modification of Fig. 9. As in the above-described embodiment, in this embodiment as well, two spots, which are in contact with each other between the overlapped first metal plate 200a and the second metal plate 200b, Each of the spot welding rods 100 is provided with a rod-shaped spot welding support rod 160 to receive power from a power supply unit, a connection portion 164 to be coupled to the spot welding support rod 160 A first electrode tip 130 coupled to an end of the spot welding support rod 160 and a second electrode tip 140 coupled to an end of the connection portion 164.

The connection portion 164 may be formed with a hollow portion and may be coupled to the outer circumferential surface of the spot welding support bar 160. The connection portion 164 may extend to surround the outer surface of the end portion of the spot welding support bar 160, The annular groove 162 is formed at the end of the annular groove. Accordingly, the first electrode tip 130 and the second electrode tip 140 can be coupled to each other in the same manner as in FIG.

The inner side surface of the connecting portion 164 is formed with an inner inclined surface 165 to correspond to the lower inclined surface 163 and the lower inclined surface 163 is formed on the outer surface of the middle portion of the cylindrical spot- And the connecting portion 164 can be easily coupled to the cylindrical spot-welding support bar 160. [ Hereinafter, the structure and the combination of the first electrode tip 130 and the second electrode tip 140 are the same as those of the embodiment of FIG.

Therefore, in this embodiment, the electric resistance spot welder of the double electrode according to the present invention can be easily formed by attaching the connecting portion 164 to the conventional spot electrode of the single electrode.

The scope of the present invention is not limited to the above-described embodiments, but may be embodied in various forms of embodiments within the scope of the appended claims. It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention as defined by the appended claims.

100: Spot electrode 100a: First spot electrode
100b: second spot welding rod 110: first spot welding support rod
111: slope 112: cooling water space
114: cooling water injection tube 120: second spot welding support rod
121: sloped surface 130: first electrode tip
131: sloped surface 132: groove
134: round rod 135: first electrode tip contact surface
140: second electrode tip 141: inclined surface
142: groove 144: hole
145: second electrode tip contact surface 150: spot welding support rod
152: groove 153: inner side surface in the groove, inclined surface
154: outer side surface in the groove, inclined surface 160: spot welding support rod
162: groove 163: inclined surface
164: connecting portion 165: inclined surface
200: metal plate 200a: first metal plate
200b: second metal plate material

Claims (27)

And a spot electrode having an electrode formed on one end of the first metal plate and the second metal plate overlapping the metal plate and contacting the metal plate and performing spot welding,
The spot electrode
A first spot welding support bar in the form of a bar that receives power from the first power supply;
A second spot welding support bar in the form of a rod receiving power from a second power supply and receiving the first spot welding support bar so as to be spaced apart from the first spot welding support bar;
A first electrode tip coupled to an end of the first spot weld support bar; And
And a second electrode tip coupled to an end of the second spot weld support bar for receiving the first electrode tip therein,
And a double composite electrode tip capable of individually controlling a current supplied to the first electrode tip from the first power supply unit and a current supplied to the second electrode tip from the second power supply unit. The method according to claim 1,
Wherein the first spot welding support bar and the second spot welding support bar are each formed of a cylindrical bar and the first spot welding support rods are disposed concentrically within the second spot welding support bar, . The method according to claim 1,
Wherein the first electrode tip is formed with a recessed groove at an end of the first electrode tip to extrude the recess of the first spot welded support rod at an end of the first spot welded support rod and the first electrode tip is coupled to the first spot welded support rod, Wherein the electric resistance spot welder has an electric resistance. The method of claim 3,
A first inclined surface is formed on the outer surface of the end portion of the first spot welding support rod and a second inclined surface corresponding to the first inclined surface is formed on the inner side surface of the depressed portion of the first electrode tip, Wherein the electric resistance spot welder has an electric resistance. The method according to claim 1,
And an end of the second electrode tip is inserted into an inner surface of the end portion of the second spot welding support rod, and the second electrode tip is coupled to the second spot welding support rod. 6. The method of claim 5,
A second electrode tip having a third inclined surface formed on the inner surface of the end portion of the second spot welding support rod and a fourth inclined surface corresponding to the third inclined surface formed on the outer surface of the end portion of the second electrode tip, Electric resistance spot welder. The method according to claim 1,
A circular rod having a circular cross-section is formed on the bottom of the first electrode tip,
And a hole for inserting the circular rod is formed in the lower portion of the second electrode tip so that the one end face of the circular rod of the first electrode tip is exposed to contact the metal plate. The method according to claim 1,
When the first spot electrode and the second spot electrode, which are disposed opposite to both sides of the overlapped metal plate, contact both surfaces of the metal plate,
A first electrode tip of the first spot electrode; a first electrode tip of the first spot electrode; a second electrode tip of the second spot electrode; a first spot weld of the second spot electrode; And a first power supply circuit connected in series to the first power supply unit,
A second electrode tip of the first spot welding electrode; a second electrode tip of the second spot welding electrode; a second spot welding of the second spot welding electrode; An electrical resistance spot welder having a double composite electrode tip constituting a second closed electrical circuit connected in series with the support bar and the second power supply. The method according to claim 1,
The electric resistance spot welder according to any one of claims 1 to 5, further comprising: a cooling water inlet tube for injecting cooling water into the cooling water space. The method according to claim 1,
Wherein the one end surface of the first electrode tip and the one end surface of the second electrode tip simultaneously contact the metal plate. The method according to claim 1,
And the second electrode tip has a double-composite electrode tip for heating the metal plate by generating resistance heat when a current is supplied from the second power supply unit. The method according to claim 1,
Wherein the strength of the power supplied from the first power supply unit and the second power supply unit, the material of the first electrode tip and the second electrode tip, or the material of the first electrode tip and the second electrode tip are in contact with the metal plate And a width of the contact area, and performing spot welding with respect to different types of metal plate members. And a spot electrode having an electrode formed on one end of the first metal plate and the second metal plate overlapping the metal plate and contacting the metal plate and performing spot welding,
The spot electrode
A rod-shaped spot welding support rod supplied with power from a power supply unit;
A first electrode tip coupled to an end of the spot weld support bar; And
And a second electrode tip coupled to an end of the spot welding support bar for receiving the first electrode tip therein,
Wherein the spot welding support bar has an annular groove formed at an end of the spot welding support rod and a double composite electrode tip in which the first electrode tip and the second electrode tip are coupled to the annular groove. delete 14. The method of claim 13,
Wherein the first electrode tip is formed with a recessed groove at an end thereof and the grooved groove of the first electrode tip is extrapolated at an inner side surface of the annular groove and the first electrode tip is coupled to the spot welding support rod An electrical resistance spot welder having a composite electrode tip. 14. The method of claim 13,
Wherein an end of the second electrode tip is inserted into the annular groove outer side surface and the second electrode tip is coupled to the spot welding support rod. And a spot electrode having an electrode formed on one end of the first metal plate and the second metal plate overlapping the metal plate and contacting the metal plate and performing spot welding,
The spot electrode
A rod-shaped spot welding support rod supplied with power from a power supply unit;
A connection portion coupled to the spot welding support bar;
A first electrode tip coupled to an end of the spot weld support bar; And
And a second electrode tip coupled to an end of the connection portion and receiving the first electrode tip therein,
Wherein the connection portion is formed with a hollow and is coupled to an outer circumferential surface of the spot welding support rod and extends to surround and surround the end portion of the end portion of the spot welding support rod to form an annular groove at an end of the spot welding support rod and the connection portion, Wherein the first electrode tip and the second electrode tip are coupled to a groove of the second electrode tip. delete 18. The method of claim 17,
The inner surface of the hollow portion of the connection portion where the hollow is inserted to be inserted into the spot welding support bar is formed with an inner inclined surface corresponding to the side inclined surface, ≪ / RTI > having a double composite electrode tip. 18. The method of claim 17,
Wherein the first electrode tip is formed with a recessed groove at an end thereof and the grooved groove of the first electrode tip is extrapolated at an inner side surface of the annular groove and the first electrode tip is coupled to the spot welding support rod An electrical resistance spot welder having a composite electrode tip. 18. The method of claim 17,
Wherein an end of the second electrode tip is inserted into an outer side surface of the annular groove and the second electrode tip is coupled to the connection portion. The method according to claim 13 or 17,
A circular rod having a circular cross-section is formed on the bottom of the first electrode tip,
And a hole for inserting the circular rod is formed in the lower portion of the second electrode tip so that the one end face of the circular rod of the first electrode tip is exposed to contact the metal plate. 21. The method according to claim 15 or 20,
And a second inclined surface corresponding to the first inclined surface is formed on the inner side surface of the depressed portion of the first electrode tip so as to be inserted and coupled to the inner surface of the annular groove, Resistance spot welder. The method according to claim 16 or claim 21,
A third inclined surface is formed on the outer side surface in the annular groove, and a fourth inclined surface corresponding to the third inclined surface is formed on the outer surface of the end of the second electrode tip, Spot welder. The method according to claim 13 or 17,
And a cooling water injection tube for injecting cooling water inserted into the cooling water space, wherein the cooling water space is formed in the inside of the spot welding support rod for injecting cooling water. The method according to claim 13 or 17,
Wherein the one end surface of the first electrode tip and the one end surface of the second electrode tip simultaneously contact the metal plate. The method according to claim 13 or 17,
Wherein the second electrode tip has a double composite electrode tip for heating the metal plate by generating resistance heat when a current flows through the power supply unit.

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