JPH091357A - Capacitor stud planting machine by welding - Google Patents

Abstract

PURPOSE: To obtain a capacitor stud planting machine by welding to be used for pulling out work of a base metal of a vehicle body of an automobile, etc., which is deformed to a recessed shape. CONSTITUTION: A stud planting machine by welding 1, which executes stud planting by welding with DC generated by the rectifying circuit of the secondary side of a power source transformer 2, has a first DC supply circuit 3 to rectify AC from a supply power source 9 with the secondary side of a power source transformer and to supply DC to an output terminal 3d and a second DC circuit 5 and a third DC supply circuit 6 in parallel with the first DC supply circuit, and capacitors C2 .C3 having a capacity different from the first DC supply circuit are arranged to these second and third DC supply circuits. By this method, corresponding to a quantity of an insulating material stuck to a base metal 10 to be planted by welding or engaging fitting 11 to be planted by welding, a control circuit which successively executes switching of an output load of each DC supply circuit, is constituted and then an oxide film of the base metal to be planted by welding is successively carbonized so as to prevent generation of much spark and an explosion state, thereby stud planting by welding is made possible without piercing the vehicle base metal.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a condenser / stud welding machine for use in drawing out a base material of a vehicle body that has been deformed into a concave shape in sheet metal work for an automobile or the like.

[0002]

2. Description of the Related Art When performing sheet metal work on a base material of a vehicle body in which a vehicle body is deformed in a concave shape due to a vehicle accident or the like, a puller or the like is used for pulling out the concavely deformed portion prior to the sheet metal processing. Although it is performed by using it, welding of an engaging metal fitting such as a washer that engages with a tool such as a puller is performed on the deformed vehicle body base material side. As the stud implanting machine used for implanting the engaging metal fittings, those having an AC output circuit or a DC output circuit as shown in FIGS. 2 to 3 are generally popular.
In the description of the conventional stud-welding machine having an AC output circuit or a DC output circuit, the same reference numerals are used for the duplicated reference numerals used in the description of FIGS. 2 to 3.

FIG. 2 is a block diagram for explaining the circuit configuration of a conventional AC stud implanter 1a with AC output. In FIG. 2, the stud implanter having this AC output circuit is in phase with the power transformer 2. Control circuit 3b
It is composed of a hand switch 8, an output terminal 3d, and a welded portion 4.

The AC stud welder 1a having these configurations will be described with reference to the block diagram of FIG. The current supplied from the power supply 9 is input to the primary side of the power transformer 2 via the phase control circuit 3b, adjusted to a predetermined voltage, and then output to the welding unit 4 on the secondary side. One of the outputs to the welded portion 4 is output from the output terminal 3d to the stud gun 4a holding the washer which is the engaging fitting 11 for the stud through the welded cable 4c, and the other output is output from the output terminal 3d. It is connected as a ground 4b to the vehicle body base material 10 in the vicinity of the portion to be subjected to the stud processing via the welding cable 4c. When the hand switch 8 is started, a current load is started and stud welding is performed.

FIG. 3 is a block diagram for explaining the circuit configuration of a conventional DC stud implanter 1b with a DC output. The DC stud implanter 1b having the DC circuit shown in FIG. 2 and rectifier circuit 3c
It comprises a first switching element SW1, a second switching element SW2, a capacitor C1, a timing circuit 7, an output terminal 3d hand switch 8 and a welding unit 4.

The direct current stud welding machine 1b having this configuration will be described with reference to the block diagram of FIG. 3. The current supplied from the power supply 9 is input to the primary side of the power transformer 2 and the secondary voltage is adjusted after a predetermined voltage adjustment. On the side, the rectification circuit 3c converts to DC.

A first switching element SW1 is provided between the positive output of the rectifying circuit 3c and one terminal of the output terminal 3d.
And a second switching element SW2, and the minus output of the rectifier circuit 3c and the other terminal of the output terminal 3d are connected. And the first switching element S
The positive terminal of the capacitor C1 is connected between W1 and the second switching element SW2, and the negative terminal of the capacitor C1 is connected to the negative output of the rectifier circuit 3c.

The charge / discharge of the electric charge to the capacitor C1 is performed by controlling the operation of the timing circuit 7 to switch the operation of the first switching element SW1 and the second switching element SW2. That is, the load of the stud power on the welding unit 4 controls the timing circuit 7 in which the first switching element SW1 is turned off and the second switching element SW2 is turned on by starting the hand switch 8, and the capacitor Charge accumulated in C1 is output terminal 3d
It is carried out by outputting to a stud gun holding a washer which is an engaging metal fitting for a stud via an output cable. In this case, the other output terminal 3d is a portion to be subjected to a stud process via the welding cable 4c. A ground 4b is formed on the vehicle body base material 10 in the vicinity of.

The charging of the capacitor C1 is performed by controlling the timing circuit 7 so that the first switching element SW1 is turned on and the second switching element SW2 is turned off when the stud implantation is completed. Done.

[0010]

However, when such stud welding is performed, the paint or oil usually attached to the welding surface of the base material of the vehicle body, or the engaging metal fittings that abut the welding surface. Adhering oil and dust are removed, but if this removal process is not complete or the oxide film formed on the surface of these metals becomes an insulator, it will be good if a large amount of current is applied in such a situation. Since there is no electrical continuity, a large amount of sparks and sometimes an explosive state may occur, and the explosion may cause holes in the vehicle body base material 10 to make it unsuitable for practical use.

Therefore, the present invention has been made to solve these problems, and the second DC supply circuit to the third DC supply circuit for disposing the capacitor are provided on the surface of the vehicle body base material or the engaging fitting. Capacitor stud welding machine that sequentially carbonizes the oxide film generated on the surface to prevent the generation of a large amount of sparks and the state of explosion and enables good stud welding without forming holes in the vehicle base metal. The purpose is to provide.

[0012]

The present invention has been made to achieve these objects, and a first feature of the means for solving the problems of the present invention is to provide a secondary power transformer. The first DC supply circuit that rectifies the AC current from the power supply at the secondary side of the power transformer and supplies the DC current to the output terminal in the stud implanter that performs the stud implantation by the DC current generated by the rectification circuit on the side And a second DC supply circuit and a third DC supply circuit in parallel with the first DC supply circuit on the secondary side of the power transformer, these second DC supply circuit, the third DC By providing a capacitor with a capacity different from that of the first DC supply circuit in the supply circuit, the output of each DC supply circuit can be adjusted according to the amount of insulation attached to the base material to be welded or the metal fitting to be welded. Switching the load sequentially Is that a structure having a control circuit.

Further, as a second feature, the capacitor capacity provided in the second DC supply circuit to the third DC supply circuit is smaller than the capacitor capacity provided in the first DC supply circuit. That is.

[0014]

In the capacitor / stud welding machine according to the present invention, when the current is output to the stud gun for implantation, the timing circuit precedes the charge output from the first conventional DC supply circuit and the timing circuit is the secondary side of the power transformer. A second direct current supply circuit provided in parallel with the first direct current supply circuit behind the rectifier circuit of
Alternatively, the electric charge accumulated in the capacitor provided in the third DC supply circuit is sequentially output according to the oxidation state of the vehicle body base material and the engagement fitting.

That is, due to the charge load of the second DC supply circuit, the insulating material such as paint, oil or oxide film adhered to the surface of the vehicle body base material or the engaging metal fittings is carbonized to cause conduction failure. Although the removal is performed, when the removal of the insulator is incomplete, the charge of the third DC supply circuit is further loaded to remove the insulator. After this removal process is completed and a good welded state is achieved, the charge of the first DC supply circuit is applied, and the metal fittings that engage the base metal of the vehicle body are not accompanied by a spark or explosion due to the welded state. Melting is done. On the other hand, for charging the capacitors of the first DC supply circuit to the third DC supply circuit, the first switching element SW1 is turned ON after the stud welding as the output of the first DC supply circuit is completed, Each capacitor C of each DC supply circuit
1, C2, C3.

[0016]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the condenser / stud welding machine of the present invention will be described with reference to the drawings. Of the reference numerals used in the reference drawings of the embodiments, the same reference numerals as those used in the above description of the prior art have the same constituent elements, and the description thereof will be omitted.

FIG. 1 is a block diagram for explaining one embodiment of the condenser / stud welding machine according to the present invention. In FIG. 1, reference numeral 1 indicates a condenser / stud welding machine, and the condenser / stud welding machine 1 includes a power transformer 2, a rectifier circuit 3c, a first DC supply circuit 3, and a second DC supply. Circuit 5 and third DC supply circuit 6
And the timing circuit 7 and the melted portion 4.

The first DC supply circuit 3 is composed of a first switching element SW1, a second switching element SW2 and a capacitor C1, and the positive terminal of the capacitor C1 is connected to the positive output side of the rectifier circuit 3c. The first switching element SW1 and the second switching element SW2 are arranged with the terminal sandwiched therebetween. The negative terminal of the capacitor C1 is connected to the negative output of the rectifier circuit 3c, and the negative terminal of the capacitor C1 and the capacitors C2 and C2 arranged in each of the second DC supply circuit 5 and the third DC supply circuit 6 which will be described later. C3
Is connected to the negative terminal of. The positive terminals of the capacitors C2 and C3 are connected to the positive output side first switching element S of the rectifier circuit 3c via a resistor.
It is connected between W1 and the second switching element SW2.

The second DC supply circuit 5 is a capacitor C2 and a third switching element SW3, and the third DC supply circuit 6 is a capacitor C3 and a fourth switching element SW4.
And are arranged in parallel with the first DC supply circuit 3.

The welded portion 4 comprises a stud gun 4a, a welded cable 4c and a ground 4b.
The metal fittings (washers) 11 are clamped by a
Stud welding to 0 is done, but this stud gun 4
The welding current is supplied to a by the output from the first DC supply circuit via the welding cable 4c.

Reference numerals 5 to 6 are the second DC supply circuit or the third DC supply circuit. The charge storage capability of the capacitor C2 or C3 arranged in these DC supply circuits is the first DC supply circuit. The capacity is extremely small as compared with the storage capacity of the capacitor C1 arranged in the circuit 3, and the stud implantation is impossible due to the discharge of the charge stored in the capacitor C2 or the capacitor C3. Furthermore, the capacitance of the capacitor C2 of the second DC supply circuit 5 and the capacitor C2 of the third DC supply circuit 6
In the comparison of the capacities of No. 3 and No. 3, the capacity difference between the two is set according to the specifications of the vehicle body base material 10 and the engaging fitting 11 which are desired objects to be melted.

A timing circuit denoted by reference numeral 7 controls the DC output of the first DC supply circuit 3 to the third DC supply circuit 6, and the timing circuit 7 includes the first switching elements SW1 to SW4. In addition to being connected to each of the switching elements SW4, their operations are specifically controlled as described later in the description of operations.

Reference numeral 8 is a hand switch. When the hand switch 8 is turned on, stud welding is executed, and OF
Canceled by F. That is, the hand switch 8 is a switch for operating the start and end of the condenser / stud welding machine 1, and the operation of the hand switch 8 starts and ends the control of the timing circuit 7.

Explaining the function of the condenser / stud welding machine 1 configured as described above, the direct current output from the rectifier circuit 3c is controlled by the respective switching elements of the timing circuit 7 so as to control the direct current. The electric charge is stored in each capacitor arranged in the DC supply circuit.

First, prior to the stud welding, the second DC supply circuit 5 discharges the stud gun 4a and the earth 4b of the welding portion 4 through the output terminal 3d. Alternatively, the engaging fitting 1 attached to the tip of the stud gun 4a and abutting on the vehicle body base material 10
The carbonization of the remaining paint / oil that adheres to the contact point of 1 is achieved, and it fulfills the function of preventing sparks and explosion due to heating of the insulator in the later stud welding.

Further, when the amount of discharge of the second DC supply circuit 5 is insufficient and carbonization of the paint / oil remaining at the expected contact position is not achieved, the third DC supply circuit 6 is arranged. The capacitor C3 is discharged and has a function of performing a compensation process for removing an insulator.

The output timing of the output current from the second DC supply circuit 5 to the third DC supply circuit 6 can be arbitrarily set by the control of the timing circuit 7, and the output current value can also be set to the first value. It can be arbitrarily set by the charging voltage of the capacitors C2 to C3 arranged in the second DC supply circuit 5 to the third DC supply circuit 6 and the capacity of the capacitor, and further, the vehicle body base material that is the body to be melted 1
Needless to say, it is also possible to change the value depending on 0, the material of the engaging fitting 11, the thickness, and the like.

Explaining the operation of the condenser / stud welding machine 1 having these functions, first, the power supply 9 is turned on and the main switch 3a is turned on to enter the stud waiting state. At the same time, the rectifying circuit 3c is activated. After that, the current is charged in the capacitors C1 to C3. At this time, the first switching element SW1 is in the ON state, and the second switching element SW2 to the fourth switching element SW4 are in the OFF state.

When an operator turns on the hand switch 8 to carry out stud welding, signals (gate signals) are sent from the timing circuit 7 to the first switching element SW1 to the fourth switching element SW4 in the following order, and the stud is turned on. The hot-melting process is started.

In the second DC supply circuit 5, the charge accumulated in the capacitor C2 in advance is the stud gun 4a of the welded portion 4.
Is output, and carbonization of the insulating material such as paint and oil remaining after the removal of the insulating material adhering to the abutting surfaces of the vehicle body base material 10 and the engaging metal fitting 11 by heating is achieved.

When carbonization of the paint / oil insulator remaining at the contact point due to the discharge of the capacitor C2 of the second DC supply circuit 5 is insufficient, the fourth switching element SW4 is turned on and another switching operation is performed. A gate signal for turning off the element is sent to each switching element, the electric charge accumulated in the capacitor C3 of the third DC supply circuit 6 is output to the stud gun 4a of the welded portion 4, and the remaining paint. Filling work for carbonization of insulation such as oil is performed.

After these processes are performed, the first switching element SW1, the third switching element SW3, and the fourth switching element SW1.
The OFF gate signal is applied to the second switching element SW4.
An ON gate signal is sent to the switching element SW2 to start stud welding. It should be noted that after the completion of the stud welding, the first switching element SW1 is turned on and the capacitors C1, C2 and C3 are charged.

[0033]

According to the present invention as described above, the following effects can be obtained. That is, the discharge of the capacitors provided in the second DC supply circuit and the third DC supply circuit causes the paint and the oil content adhering to the contact points of the vehicle body base material and the engaging metal fittings that contact the vehicle body base material. Since carbonization of insulators such as oxide films is sequentially achieved, it is possible to prevent the generation of a large amount of sparks and the explosion state due to the remaining insulators that have frequently occurred in the past, and to prevent holes from being formed in the base metal of the vehicle body due to the explosion. This has the effect of enabling favorable stud welding without causing the above.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating an embodiment of a condenser / stud welder according to the present invention.

FIG. 2 is a block diagram illustrating a circuit configuration of a conventional AC stud implanter with AC output.

FIG. 3 is a block diagram illustrating a circuit configuration of a conventional DC stud implanter with DC output.

[Explanation of reference symbols] 1 condenser stud implanter 1a AC stud implanter 1b DC stud implanter 2 power transformer 3 first DC supply circuit 3a main switch 3b phase control circuit 3c rectifier circuit 3d output terminal 4 implant Part 4a Stud gun 4b Earth 5 Second DC supply circuit 6 Third DC supply circuit 7 Timing circuit 8 Hand switch 9 Power supply 10 Body material 11 Engagement fitting (washer) C1 Capacitor (First DC supply circuit) C2 capacitor (second DC supply circuit) C3 capacitor (third DC supply circuit) SW1 first switching element SW2 second switching element SW3 third switching element SW4 fourth swinging element

Claims (2)

[Claims] 1. A stud implanter for performing stud implantation using a DC current generated by a rectifier circuit on the secondary side of a power transformer, rectifying an AC current from a power supply on the secondary side of the power transformer and outputting a DC current. A first direct current supply circuit for supplying to a terminal, and a second direct current supply circuit and a third direct current supply circuit in parallel with the first direct current supply circuit on the secondary side of the power transformer. By arranging the second DC supply circuit and the third DC supply circuit with capacitors having different capacities from the first DC supply circuit, it is possible to reduce the amount of insulation adhered to the base material to be melted or the metal fittings to be melted. Correspondingly, the capacitor / stud welder has a control circuit for sequentially switching the output load of each DC supply circuit. 2. The capacitor capacity provided in the second DC supply circuit to the third DC supply circuit is smaller than the capacitor capacity provided in the first DC supply circuit. 1. Capacitor stud welding machine described in 1.