JP2003136250A - Resistance welder for coated conductor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resistance welder for coated conductor which is suitable for a work having a large number of contacts without generating useless consumables. SOLUTION: This resistance welder for coated conductor is provided with a thermal electrode part 12 which has a heating mechanism 11 for stripping a coating 1a by fusion, an electrode part 13 arranged at a naked conductor 2, a welding circuit 14 arranged so as to apply a welding current Iw between both electrodes 12, 13, a heating circuit 15 arranged so as to apply a heating current Ih to the heating mechanism 11, a current detecting means (toroidal coil 16) which detects that the coating 1a is stripped by fusion and the welding current Iw starts to flow, a switch 17 which switches the heating circuit 15 and a control means 18 which controls the switch 17 so as to intercept a current which branches from the welding circuit 14 to the heating circuit 15.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resistance welding machine for coated conductors using a hot electrode section.

[0002]

2. Description of the Related Art Conventionally, various resistance welding machines have been developed as a device for welding a coated conductor such as a coated electric wire to another conductor or coated conductors.

For example, in Japanese Unexamined Patent Publication No. 2000-101229, a ribbon material for generating Joule heat is provided between welding electrode parts, and a current is applied to the ribbon material to heat a coated conductor to melt the insulating coating. After that, a technique of welding conductors to each other is disclosed. In addition, JP-A-8-392
In Japanese Patent Laid-Open No. 64, No. 64, Joule heat is generated in one conductor to be welded by using a bifurcated two-point contact type electrode part and one-point contact type electrode part, and the other coated conductor is heated by the heat. Then, the technique of melting an insulating coating is disclosed.

[0004]

[Patent Document 1] Japanese Unexamined Patent Application Publication No.
The apparatus disclosed in Japanese Patent Laid-Open No. 000-101229 is not preferable because a consumable item such as a ribbon material is required as a heating member. Further, in the technique disclosed in Japanese Patent Laid-Open No. 8-39264, since it is necessary to push the work into the inside of the bifurcated two-point contact type electrode portion, like the circuit used for the electrical connection box of the wire harness, It cannot be applied when a large number of contacts need to be formed on the same conductor.

The present invention has been made in view of the above problems, and an object of the present invention is to provide a resistance welding machine for coated conductors suitable for a work having a large number of contacts without generating wasteful consumables. There is.

[0006]

In order to solve the above-mentioned problems, the present invention provides a resistance welding machine for a coated conductor for welding a coated conductor coated with an insulator and a bare conductor, A hot electrode section that has a heating mechanism that generates Joule heat for melting and peeling the coating of the coated conductor, an electrode section that is provided for a bare conductor, and welds both conductors by generating Joule heat. A welding circuit for supplying a welding current for flowing between the two electrode portions, and a heating current for generating a Joule heat to heat the heating mechanism, and shunting the heating current to the heating mechanism. A heating circuit provided in the welding circuit, a current detection means for detecting that the coating of the coating conductor is melted and peeled off and a welding current starts to flow in the welding circuit; and the heating circuit, A switch for opening and closing the heating circuit, A resistance welding machine for coated conductors, comprising: a control means for controlling the switch so as to cut off a current diverted from the welding circuit to the heating circuit in response to the detection of the welding current by the flow detection means. Is.

According to the present invention, when welding the covered conductor covered with the insulator and the bare conductor, a heating current is passed through the heating circuit to heat the heating mechanism of the hot electrode section. The coating of the coated conductor can be melt stripped.
Further, since the current detecting means detects that the coating of the coated conductor is melted and peeled off and the welding current begins to flow between the two electrode parts, and the switch of the heating circuit is opened, the conductor is welded. During that time, the current shunting from the welding circuit to the heating circuit can be interrupted.

Next, another aspect of the present invention is a resistance welding machine for coated conductors for welding coated conductors coated with an insulator, which is for melting and peeling each coating of the coated conductors. A pair of hot electrode portions having a heating mechanism for generating Joule heat, and a welding circuit provided so as to flow a welding current for generating Joule heat to weld both conductors between the pair of hot electrode portions, A heating circuit for generating Joule heat to heat each of the heating mechanisms, the heating circuit being shunted from the welding circuit to flow into each heating mechanism, and provided in the welding circuit. Current detection means for detecting that the coating has been melted and peeled off and welding current has begun to flow in the welding circuit, a switch provided in the heating circuit for opening and closing the heating circuit, and a welding current by the current detection means. Welding times corresponding to detection A coated conductive collector resistance welding machine, characterized in that a control means for controlling the switch so as to interrupt a current shunted to the heating circuit from.

According to this aspect, when welding the coated conductors coated with the insulating material, a heating current is passed through the heating circuit to heat the heating mechanism of the pair of hot electrode portions.
The coating of each coated conductor can be melt stripped. In addition, the current detecting means detects that the coating of each coated conductor is melted and peeled off and the welding current begins to flow between both electrode parts, and the switch of the heating circuit is turned off, so that both conductors are welded. During this time, the current shunting from the welding circuit to the heating circuit can be interrupted.

A preferred embodiment of the present invention is the resistance welding machine for coated conductors, wherein the heating circuit is a circuit configured to flow a heating current in series in each heating mechanism. .

According to this preferred embodiment, since the heating circuit is configured to flow a heating current in series to each heating mechanism, only one switch for interrupting the heating current needs to be provided, The device can be simplified.

[0012]

BEST MODE FOR CARRYING OUT THE INVENTION A first embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

FIG. 1 is a conceptual diagram showing the structure of a resistance welding machine 10 for coated conductors according to a first embodiment of the present invention. Further, FIG. 2 is a conceptual diagram showing a circuit configuration of the resistance welding machine for coated conductors 10 according to the first embodiment of the present invention.

With reference to these figures, a resistance welding machine 10 for a coated conductor according to the illustrated first embodiment welds a coated conductor 1 covered with an insulator and a bare conductor 2. Which is a resistance welding machine for the coated conductor 1 and has a heating mechanism 11 and a heating electrode 11, an electrode portion 13 provided for the bare conductor 2, and Joule heat. A welding circuit 14 provided so that a welding current Iw for welding both conductors 1 and 2 is passed between the two electrode parts 12 and 13;
The heating current Ih for generating Joule heat to heat the heating mechanism 11 is shunted from the welding circuit 14 to generate the heating mechanism 11.
The heating circuit 15 and the welding circuit 14 that are provided so as to flow
Toroidal coil 16 (current detecting means) for detecting that the welding current Iw has started to flow, a switch 17 provided in the heating circuit 15 for opening and closing the heating circuit 15, and a control means 18 for controlling the switch 17. It has and.

In the heating mechanism 11, a material made of a metal having a high electric resistance, such as tungsten or molybdenum, is arranged in a bridge shape, a heating current Ih is passed through the material to generate Joule heat, and the Joule heat is applied to cover the material. Coating 1 for conductor 1
It is configured to melt and peel a.

In the hot electrode portion 12, the heating mechanism 11 is arranged at the curved portion of the U-shaped portion formed of a member of a good electric conductor such as copper provided on the side of the coated conductor 1, and the heating current is placed there. I
flowing h to generate Joule heat at the tip of the hot electrode part,
This is an electrode portion configured to melt and peel off the coating 1a of the coated conductor 1 by this Joule heat. Furthermore, after the coating 1a of the coated conductor 1 is melted and peeled off, a welding current is passed through the conductors 1 and 2 to generate Joule heat in the conductors 1 and 2, and the Joule heat causes the Joule heat to occur in the conductors 1. 2 are welded together.

The hot electrode portion 12 is driven by an elevator device (not shown) such as an air cylinder to drive the electrode portion 1.
The conductor receiving posture in which the gap between the electrodes 2 and 13 is widened, and the gap between the electrode portions 12 and 13 is narrowed, and the conductors 1 and 2 are interposed therebetween.
It is adapted to be displaced with respect to the conductor welding position in which the is clamped.

The electrode portion 13 is a normal electrode portion provided for the bare conductor 2, and a tip portion made of a metal having a high melting point temperature is arranged at the tip of a member made of a metal such as copper. After the coating 1a of the coated conductor 1 is melted and peeled off, a welding current is applied to both conductors 1 and 2 in cooperation with the hot electrode portion 12 to weld both conductors 1 and 2. It is the electrode part.

In the welding circuit 14, the welding current I is applied to the contact portion between the conductors 1 and 2 via the hot electrode portion 12 and the electrode portion 13.
It is an electric circuit provided for flowing w to melt and bond both conductors 1 and 2. The welding current Iw is from the welding power source 19 to the hot electrode portion 12, both conductors 1 and 2, normal electrodes. It is configured to pass through the portion 13 and return to the welding power source 19 again.

The heating circuit 15 supplies a heating current Ih to the heating mechanism 11 to generate Joule heat, and the heating mechanism 11
Is an electric circuit provided for melting and peeling off the coating 1a of the coated conductor 1 which is in contact with the welding conductor. The heating current Ih passes from the welding power source 19 through the hot electrode portion 12 and the heating mechanism 11 and then the welding circuit It is configured such that the flow is branched from 14 and passes through the switch 17, and then merges with the welding circuit 14 again and returns to the welding power source 19.

The toroidal coil 16 is the welding circuit 1
4 is a current detection means provided so as to surround the welding circuit 14 between the confluence of the heating circuit 15 and the welding circuit 14 and the electrode portion 13, and the coating 1a of the coating conductor 1 is melted and peeled off. The fact that the welding current Iw begins to flow in the welding circuit 14 is detected by measuring the magnitude of the induced electromotive force generated by the welding current Iw in the toroidal coil 16.

The switch 17 is a switch mechanism which is provided in a portion of the heating circuit 15 where the current is divided from the welding circuit 14 and merges again, and which can open and close the current flowing through the heating circuit 15. In the present embodiment, the switch 17 is driven by driving an air cylinder (not shown) in response to the detection of the welding current Iw of the toroidal coil 16.
Is configured to open and close.

The control means 18 is for controlling the operation of each part of the resistance welding machine 10 for the coated conductor, and includes an operation switch, a current detection signal of the toroidal coil 16, and the like.
A microprocessor that operates based on an input signal from each unit and an electrical component connected to the microprocessor are provided.

The control means 18 detects the value of the welding current Iw by measuring the magnitude of the induced electromotive force generated by the welding current Iw with respect to the toroidal coil 16, and corresponds to the detection of the welding current Iw. Then, the switch 17 is controlled so as to cut off the current shunting from the welding circuit 14 to the heating circuit 15. Further, the hot electrode unit 12 is driven by an elevating device (not shown) so that the hot electrode unit 12 is displaced between the conductor receiving posture in which the gap between the electrode units is widened and the conductor welding posture in which the gap between the electrode units is narrowed. It controls and controls the energization of the welding circuit 14 and the heating circuit 15 from the welding power source. Further, in a state where welding of both conductors 1 and 2 is in progress, the control means 18 monitors the welding current Iw of the toroidal coil 16 and the welding current Iw flowing through the welding circuit 14.
Is controlled to control the welding power source 19 to an appropriate value.

Next, the operation of the first embodiment will be described with reference to FIGS.

Referring to FIG. 1, both conductors 1 and 2 are manually or manually inserted between the hot electrode portion 12 and the electrode portion 13 in a conductor receiving posture in which the distance between the electrode portions 12 and 13 is increased. , Automatically transported. Then, an elevating device (not shown) such as an air cylinder is driven to lower the hot electrode portion 12, and the carried conductors 1 and 2 are sandwiched between the hot electrode portion 12 and the electrode portion 13. The heating current Ih flows through the portion 12 and the heating of the heating mechanism 11 is started.

In FIG. 2A, the heating current I is applied to the hot electrode portion 12.
Although h is flowing, the coating 1a of the conductor 1 is not yet melted, but shows an initial heating state. In this state, the heating current Ih is from the welding power source 19 to the hot electrode portion 12 and the heating mechanism 1.
1, the switch 17 flows in this order, and the Joule heat generated by the heating current Ih causes the coating 1a of the conductor 1 to melt. On the other hand, in the welding circuit 14, since the coating 1a has not been melted yet, electrical continuity has not been established at the contact portions of the two conductors 1 and 2, and as a result, the welding current Iw
Is not flowing.

Further, in FIG. 2B, the heating mechanism 11 of the hot electrode portion 12 has reached a sufficiently high temperature, and the coating 1a of the coated conductor 1 is shown.
Shows the state in which the welding current Iw begins to flow and the welding of both conductors 1 and 2 has started. In this state, the coating 1a is melted to establish electrical continuity between the contact portions of both conductors 1 and 2, and in the welding circuit 14, from the welding power source 19 to the hot electrode portion 12, both conductors 1 and 2, normally. The welding current Iw starts to flow in the order of the electrode portion 13 and the toroidal coil 16.

In this state, the control means 18 outputs a signal for turning off the switch 17 in response to the detection of the welding current Iw of the toroidal coil 16, and the switch 17 outputs an air signal (not shown) based on this signal. When the cylinder is driven, the switch 17 is turned off, and the current split from the welding circuit 14 to the heating circuit 15 is cut off.

In FIG. 2 (c), the switch 17 is turned off, the current shunting to the heating circuit 15 is cut off, the welding current Iw flows only to the welding circuit 14, and both conductors 1 and 2 are welded. Indicates that

In this state, the control means 18 monitors the welding current Iw of the toroidal coil 16 and detects the welding circuit 14
The welding power source 19 is controlled so that the welding current Iw flowing through the wire is set to an appropriate value suitable for welding the conductors 1 and 2.

As described above, according to the first embodiment, when welding the coated conductor 1 covered with the insulator and the bare conductor 2, the heating circuit 15 is supplied with the heating current Ih to heat the conductor. By heating the heating mechanism 11 of the electrode portion 12, the coating 1a of the coated conductor 1 can be melted and peeled off. Also,
The coating 1a of the coated conductor 1 is melted and peeled off, and both electrode portions 1
The toroidal coil 16 detects that the welding current has started to flow between the 2nd and 13th and turns off the switch 17 of the heating circuit 15.
Therefore, the current shunted from the welding circuit 14 to the heating circuit 15 can be interrupted while the conductors 1 and 2 are being welded.

Next, a second embodiment of the present invention will be described with reference to FIGS.

FIG. 3 is a conceptual diagram showing the structure of a resistance welding machine 20 for coated conductors according to a second embodiment of the present invention. Further, FIG. 4 is a conceptual diagram showing a circuit configuration of a resistance welding machine 20 for a coated conductor according to a second embodiment of the present invention.

With reference to these drawings, the second embodiment according to the present invention is a coated conductor in which a coated conductor 1 coated with an insulator and a coated conductor 3 coated with insulation are welded. Resistance welding machine 20 for coatings, which are coatings 1a and (3a), respectively
The welding current Iw for welding the hot electrode portions 22a and (22b) having the heating mechanisms 21a and (21b) for melting and peeling the conductors and the hot electrode portions 22a and 22b.
The welding circuit 24 provided so as to flow between the heating circuit 2 and the welding circuit 24.
The heating circuit 25 provided so as to flow the heating current Ih for heating the 1a and 21b, and the coatings 1a and (3a) of the coating conductors 1 and (3) are melted and separated, and the welding current Iw is supplied to the welding circuit 24. Toroidal coil 26 for detecting the start of flow, and switch 27 for opening and closing heating circuit 25.
And a control means 28 for controlling the switch 27 so as to interrupt the current diverted from the welding circuit 24 to the heating circuit 25 in response to the detection of the welding current Iw by the toroidal coil 26.

The heating mechanisms 21a and 21b have the same structure as the heating mechanism 21 in the first embodiment. In the second embodiment, they are provided on both sides of the coated conductors 1 and 3, respectively. Joule heat is generated to melt and separate the coatings 1a and 3a.

The hot electrode portions 22a and 22b are also electrode portions having the same structure as the hot electrode portion 12 in the first embodiment, and in the second embodiment, the curved portions of the U-shaped portion are respectively formed. The heating mechanisms 21a and 21b are arranged, and the coatings 1a and 3a of the coated conductors 1 and 3 are melted and peeled off. Further, after melting and peeling the coatings 1a and 3a of the coated conductors 1 and 3,
Welding current Iw is applied to both conductors 1 and 3 so that both conductors 1 and 3
Is configured to be welded.

The welding circuit 24 is constructed so that the welding current Iw flows from the welding power source 29 through the hot electrode portion 22a, both conductors 1 and 3, and the hot electrode portion 22b, and returns to the welding power source 29 again. .

The heating circuit 25 comprises heating mechanisms 21a and 2a.
Coatings 1a, 3a of coated conductors 1, 3 in contact with 1b
Is an electric circuit provided for melting and peeling, and flows from the welding power source 29 through the hot electrode portion 22a and the heating mechanism 21a, branches from the welding circuit 24, passes through the switch 27, and then the hot electrode portion 22b. It is configured to return to the welding power source 29 through the heating mechanism 21b. As described above, in the second embodiment, the heating circuit 25 is configured to flow the heating current Ih in series to the heating mechanisms 21a and 21b.

In the second embodiment, the toroidal coil 26 is provided so as to surround the entire U-shaped portion of the hot electrode portion 22b. Therefore, in the second embodiment, unlike the first embodiment, the heating current Ih flows through the portion surrounded by the toroidal coil 26 so that the heating current Ih flows through the toroidal coil 26. Since it flows so as to reciprocate in the enclosed portion, the directions of the induced electromotive force are canceled out, and as a result, the toroidal coil 26 does not detect the heating current Ih. The toroidal coil 26 detects the magnitude of the welding current Iw flowing between the hot electrode portions 22a and 22b, as in the first embodiment.

Next, the operation of the second embodiment will be described with reference to FIG.

Referring to FIG. 4A, in FIG. 4A, the heating current Ih flows through the hot electrode portions 22a and 22b, but the coatings 1a and 3a of the conductors 1 and 3 are not yet melted. Shows the heating state of. In this state, the heating current Ih flows from the welding power source 29 to the hot electrode portion 22a, the heating mechanism 21a, the switch 29, the hot electrode portion 22b, and the heating mechanism 21b in this order in the heating circuit 25, and the heating current Ih generates joules. The heat causes the coatings 1a and 3a of the conductors 1 and 3 to be melted. On the other hand, in the welding circuit 24, the coatings 1a and 3a are not yet melted, and the electrical conduction is not established in the contact portions of the two conductors 1 and 3, so that the welding current I
w is not flowing.

Further, FIG. 4B shows the hot electrode portions 22a, 2a.
The heating mechanisms 21a and 21b of 2b have a sufficiently high temperature, the coatings 1a and 3a of the coated conductors 1 and 3 coated with an insulator are melted and separated, and the welding current Iw starts to flow, so that both the conductors 1 and 3 are flowed. Shows the state where the welding of is started. In this state, the coatings 1a and 3a are melted and electrical continuity is established in the contact portions of the conductors 1 and 3, and as a result, in the welding circuit 24 from the welding power source 29 to the hot electrode portion 22a and the conductors 1 and 2.
3, the welding current starts to flow in the order of the hot electrode portion 22b.

On the other hand, even if the welding current Iw begins to flow in the welding circuit 24, the switch 27 of the heating circuit 25 remains closed in this state, so that the heating current Ih continues to flow in the heating circuit 25.

In this state, the control means 28 sends a signal for turning off the switch 27 so as to cut off the current shunting from the welding circuit 24 to the heating circuit 25 in response to the detection of the welding current Iw of the toroidal coil 26. put out.

In FIG. 4C, the switch 29 is turned off, the current shunting the heating circuit 25 is cut off, the welding current Iw flows only in the welding circuit 24, and both conductors 1 and 3 are welded. Indicates that

In this state, the control means 28 monitors the welding current Iw of the toroidal coil 26, and the welding circuit 24
The welding power source 29 is controlled so that the welding current Iw flowing through the valve is set to an appropriate value.

As described above, according to the second embodiment of the present invention, when welding the coated conductors 1 and 3 coated with the insulator, the heating current Ih is passed through the heating circuit 25 to generate a pair of heat. By heating the heating mechanisms 21a and 21b of the electrode portions 22a and 22b, the coatings 1a and 3a of the coated conductors 1 and 3 can be melted and peeled off. The toroidal coil 26 detects that the coatings 1a and 3a of the coated conductors 1 and 3 are melted and separated and the welding current Iw starts to flow between the electrode portions 22a and 22b, and the switch 29 of the heating circuit 25 is detected. Is turned off, it is possible to interrupt the current shunted from the welding circuit 24 to the heating circuit 25 while the two conductors 1 and 3 are being welded.

Further, since the heating circuit 25 is constructed so as to flow a heating current in series to each heating mechanism 21, only one switch for interrupting the heating current needs to be provided, which simplifies the device. Can be achieved.

The above-described embodiment is merely an example of a preferred specific example of the present invention, and the present invention is not limited to the above-described embodiment.

For example, the good conductor parts of the hot electrode parts 12, 22a, 22b and the electrode part 13 do not necessarily have to be copper, but may be made of a good electric conductor metal member.

The heating mechanisms 11, 21a and 21b are not necessarily made of tungsten or molybdenum, but have high electric resistance and generate sufficient Joule heat, and the Joule heat melts and separates the coating 1a of the coated conductor 1. Any material can be used as long as it can be used.

Current detecting means Further, not limited to the toroidal coil, any device may be used as long as it can detect the welding current Iw in the welding circuits 14 and 24.

Further, as the heating circuit 25 in the second embodiment of the present invention, as shown in FIG.
Each heating mechanism 21a, 21 from the individual welding power source 29
The heating current Ih does not have to be configured to flow in series with b, and each may have a welding power source 29 and a switch 27, and separately supply electric power.

Needless to say, various design changes can be made within the scope of the claims of the present invention.

[0056]

As described above, according to the present invention,
It is possible to realize a resistance welding machine for coated conductors suitable for a work having a large number of contacts without generating wasteful consumables.

[Brief description of drawings]

FIG. 1 is a conceptual diagram showing a configuration of a resistance welding machine for coated conductors according to a first embodiment of the present invention.

FIG. 2 is a conceptual diagram showing a circuit configuration of a resistance welding machine for coated conductors according to the first embodiment of the present invention. (A) is
A heating current is flowing in the hot electrode portion, but the initial heating state in which the conductor coating is not yet melted is shown. Also,
(B) shows a state in which the coating of the coated conductor is melted and peeled off, a welding current starts to flow, and welding of both conductors is started. (C) shows a state in which the switch is turned off, the current shunting to the heating circuit is cut off, the welding current flows only in the welding circuit, and both conductors are welded.

FIG. 3 is a conceptual diagram showing the configuration of a resistance welding machine for coated conductors according to a second embodiment of the present invention.

FIG. 4 is a conceptual diagram showing a circuit configuration of a resistance welding machine for coated conductors according to a second embodiment of the present invention. (A) is
A heating current is flowing through both hot electrode portions, but the initial heating state in which the conductor coating is not yet melted is shown. Further, (b) shows a state in which the coatings of both coated conductors are melted and peeled off, a welding current begins to flow, and welding of the conductors is started. (C) shows a state in which the switch is turned off, the current shunting to the heating circuit is cut off, the welding current flows only in the welding circuit, and both conductors are welded.

[Explanation of symbols]

1, 3 coated conductor 2 bare conductor 1a, 3a coating 10, 20 Resistance welding machine for coated conductors 11, 21a, 21b Heating mechanism 12, 22a, 22b Hot electrode part 13 Electrode part 14, 24 Welding circuit 15, 25 heating circuit 16,26 toroidal coil (current detection means) 17,27 switch 18, 28 Control device 19, 29 Welding power source Heating current Ih Welding current Iw

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification symbol FI theme code (reference) B23K 101: 38 B23K 101: 38 (72) Inventor Tatsuya Hattori 1-14 Nishisuehiro-cho, Yokkaichi-shi, Mie Sumitomo Inside Denso Co., Ltd. (72) Inventor Nobu Hattori 1-14 Nishisuehiro-cho, Yokkaichi-shi, Mie Sumitomo Denso Co., Ltd.

Claims (3)

[Claims] 1. A resistance welding machine for a coated conductor for welding a coated conductor coated with an insulator and a bare conductor, wherein Joule heat is generated for melting and peeling the coating of the coated conductor. A heating electrode part having a heating mechanism for making it possible, an electrode part provided for a bare conductor, and a welding current for generating Joule heat to weld both conductors so as to flow between the two electrode parts. A welding circuit provided, a heating circuit provided to generate a Joule heat to shunt the heating current for heating the heating mechanism from the welding circuit, and to flow the heating current to the heating mechanism; and Current detection means for detecting that the coating of the coating conductor has been melted and peeled off and welding current has begun to flow in the welding circuit; a switch provided in the heating circuit for opening and closing the heating circuit; and welding by the current detection means. Melted in response to current detection Coated conductive collector resistance welding machine, characterized in that a control means for controlling the switch so as to interrupt a current shunted to the heating circuit from the circuit. 2. A resistance welding machine for coated conductors for welding coated conductors coated with an insulator, comprising a heating mechanism for generating Joule heat for melting and peeling off each coating of the coated conductor. A pair of hot electrode parts, a welding circuit provided so as to flow a welding current for generating joule heat to weld both conductors between the pair of hot electrode parts, and generate a joule heat to generate each of the heating A heating circuit provided so as to shunt a heating current for heating the mechanism from the welding circuit and to flow to each heating mechanism, and is provided in the welding circuit, and the coating of the coating conductor is melted and peeled to the welding circuit. A current detecting means for detecting that the welding current has started to flow, a switch provided in the heating circuit for opening and closing the heating circuit, and heating from the welding circuit corresponding to the detection of the welding current by the current detecting means. Divert to the circuit And a control means for controlling the switch so as to cut off the electric current. 3. The resistance welding machine for a coated conductor according to claim 2, wherein the heating circuit is a circuit configured to flow a heating current in series to each heating mechanism. Resistance welding machine for body.