US2748237A

US2748237A - Welding apparatus

Info

Publication number: US2748237A
Application number: US439813A
Authority: US
Inventors: Laporte Edmour
Original assignee: Individual
Current assignee: Individual
Priority date: 1954-06-28
Filing date: 1954-06-28
Publication date: 1956-05-29
Anticipated expiration: 1973-05-29

Description

May 29, 1956 E. LAPORTE 2,748,237

WELDING APPARATUS Filed June 28, 1954 179/60/0/1' Zdmmz/ Japan? United The present invention pertains to a novel apparatus for arc welding.

The principal object of the invention is to provide a substantially constant voltage in welding instead of a constant amperage, thereby increasing the efiiciency of the welding operation and improving the effectiveness of the weld.

It is well known that the actual procedures of arc welding are not always satisfactory. Since the quality of the weld is a function of the voltage, the invention provides a means for handling all the power required by the arc for fusing the metal. This power is a function of El=voltage current.

Another object is to control the adjustment of the energy necessary for the arc without the use of fuses.

A further object is to provide an accumulator or battery which permits a constant arc effect, that is, stable operation with power of a half, a fourth, etc., of the maximum required without accumulation.

A still further object is to enable variations of voltage on the transformer as a function of that desired on the accumulator the latter being a function of the desired eifect at the arc.

In the accomplishment of these objects, the invention comprises the use of an accumulator to obtain a constant voltage of a given weld.

The secondary of a transformer is included in a closed circuit that contains a single-phase full wave rectifier of the undulating type, a mercury diode with two anodes, or other suitable form. This circuit is joined to a controller, that is, a solenoid adapted to open a switch in the event of a direct short circuit, the switch being connected to the metal being worked upon. Another conductor extends from the midpoint of the secondary to the welding electrode. Finally, an accumulator or battery is branched between the last named conductor and the input side of the switch and is adjustable from the conductor. A fuse or directional relay is mounted between the rectifiers and accumulator. A resistance is used to control the overcurrent relay.

The invention is fully disclosed by way of example in the following description and in the accompanying drawings in which:

The single figure is a diagram of the circuit.

As clearly indicated, the invention comprises a transformer 1 having its primary winding connected to a source of power and the ends of the secondary winding joined in a closed circuit by a conductor 2 having a junction point 3. Rectifier 4 is mounted in the conductor 2 and may be of the full wave type, mercury diode with two anodes, or other suitable form.

A conductor 5 extends from point 3 to a switch 6 and thence to the base or metal '7 on which the welding is performed. A solenoid 8 connected in parallel with the switch 6 by a conductor 9 actuates an armature 10 connected to the switch to open the switch when the output is too high.

Patent 0 ice A welding cement coated electrode 11 is connected by a conductor 12 to the midpoint of the secondary winding. The cement coating is used for the protection of the arc and the metal. To the conductor 12 is also connected a movable accumulator 14 which has one end connected to the conductor 5.

A resistance 15 is mounted between the switch 6 and the base '7 and is adjustably engaged by an end of the solenoid conductor 9, in order to vary the current flowing through the solenoid 8. A fuse or directional relay 16 is mounted in the conductor 5 between the point 3 and the battery 14.

The described circuit permits a relatively constant voltage, that is, a variation of four to five volts with twentyfive volts at the are. A constant voltage results in a uniform weld of good quality. The required voltage is a function of the size of the electrode and the desired size of are. It may be noted that existing apparatus are the cause of large variations and irregularities at the expense of power consumption. As another advantage of the invention, when the voltage at the arc is increased a cutting arc may be produced.

Although a specific embodiment of the invention has been illustrated and described, it will be understood that various alterations in the details of construction may be made without departing from the scope of the invention as indicated by the appended claims.

What I claim is:

1. A welding apparatus comprising a transformer, a conductor joining the ends of the secondary winding thereof, rectifying means in said conductor, a metal working base, a second conductor extending from the first conductor to said base, a welding cement coated electrode at said base, a third conductor extending from the midpoint of the secondary winding to said electrode, an accumulator between the second and third conductor, and an automatic switch in the second conductor between said accumulator and said base.

2. A welding apparatus comprising a transformer, a conductor joining the ends of the secondary winding thereof, rectifying means in said conductor, a metal working base, a second conductor extending from the first conductor to said base, a welding cement coated electrode at said base, a third conductor extending from the midpoint of the secondary winding to said electrode, an accumulator between the second and third conductor, a contact from said third conductor and adjustable on said accumulator, and an automatic switch in the second conductor between said accumulator and said base.

3. A Welding apparatus comprising a transformer, a conductor joining the ends of the secondary winding thereof, rectifying means in said conductor, a metal Working base, a second conductor extending from the first conductor to said base, a welding cement coated electrode at said base, a third conductor extending from the midpoint of the secondary winding to said electrode, an accumulator between the second and third conductor, a switch in the second conductor between said accumulator and said base, and a solenoid connected across said switch and having an armature conncted to said switch.

4. A Welding apparatus comprising a transformer, a conductor joining the ends of the secondary winding thereof, rectifying means in said conductor, a metal working base, a second conductor extending from the first condoctor to said base, a welding cement coated electrode at said base, a third conductor extending from the midpoint of the secondary winding to said electrode, an accumulator between the second and third conductor, a contact from said third conductor and adjustable on said accumulator, a switch in the second conductor between said accumulator and said base, and a solenoid connected across said switch and having an armature connected to said switch.

5. A welding apparatus comprising a transformer, a conductor joining the ends of the secondary winding thereof, rectifying means in said conductor, a metal working base, a second conductor extending from the first conductor to said base, a welding cement coated electrode at said base, a third conductor extending from the midpoint of the secondary winding to said electrode, an accumulator between the second and third conductor, a switch in the second conductor between said accumulator and said base, and a solenoid connected across said switch and having an armature connected to said switch, and means for adjusting the current in said solenoid.

6. A welding apparatus comprising a transformer, a

conductor joining the ends of the secondary winding thereof, rectifying means in said conductor, a metal working base, a second conductor extending from the first conductor to said base, a welding cement coated electrode at said base, a third conductor extending from the midpoint of the secondary winding to said electrode, an accumulator between the second and third conductor, a switch in the second conductor between said accumulator and said base, and a solenoid connected across said switch and having an armature connected to said switch, a resistance in the second conductor between switch and said base, one end of said solenoid being adjustably connected to said resistance.

No references cited.