 Hydraulic control valve with manual override |
| In accordance with one aspect of the invention, a manual override handle is mounted for pivoting ... |
|
| Bulkhead connector |
| AND ADVANTAGES The subject invention is directed toward a bulkhead connector assembly for ... |
|
| Streamer cable |
| OF A PREFERRED EMBODIMENT In the following detailed desription and corresponding figures, like ... |
|
| Method of attaching guideways to a machine tool bed |
| OF THE INVENTION FIGS. 1, 2 and 3 illustrate views of a fixture for precisely orienting guideways ... |
|
| Continuous compounding and mixing apparatus |
| OF THE PREFERRED EMBODIMENT Now an exemplary embodiment of this invention will be described with ... |
|
| Manure spreader |
| The present invention relates generally to a liquid and semi-liquid type manure spreader, and more ... |
|
| Drop jet apparatus |
| An object of the invention is to provide a drop jet apparatus such as an ink-jet printing apparatus ... |
|
| Drip feed device for irrigation purposes |
| I claim: 1. A drip feed device for irrigation purposes in which a body (25) has a cylindrical wall (... |
|
| Loudspeaker diaphragm |
| What is claimed is: 1. A plane-type or cone-type loudspeaker diaphragm with a foam material having ... |
|
| Ultrasonic cleaning and sterilizing apparatus |
| The present invention relates to apparatus for the ultrasonic cleaning and sterilization of soft ... |
|
|
Tandem electrode welder and method of welding with two electrodes
| Details |
Inventors: Stava, Elliott K.; Peters, Steven R.;
Assignee: Lincoln Global, Inc. (Monterey Park, CA)
Primary Examiner: Shaw; Clifford C.
Assistant Examiner:
Attorney, Agent or Firm: Vickers, Daniels & Young
An electric arc welding apparatus comprising at least a first consumable electrode and a second consumable electrode movable in unison along a welding path between the edges of two adjacent, mutually grounded plates, a first power supply for passing a first welding current at a first low frequency between the first electrode and the two plates, a second power supply for passing a second welding current at a second low frequency between the second electrode and the two plates, where each of the power supplies includes a three phase voltage input operated at line frequency, a rectifier to convert the input voltage to a DC voltage link and a high frequency switching type inverter converting the DC voltage link to a high frequency AC current, an output rectifier circuit to provide a positive voltage tenninal and a negative voltage terminal, and an output switching network operated at a given low frequency for directing a pulsating welding current at the given low frequency from the two terminals across one of the electrodes and the plates, and a circuit for independently adjusting the given low frequency so the value of the first low frequency of the first power supply is different from the second low frequency of the second power supply. |
|
DETAILED DESCRIPTION Having thus defined the invention, the following is claimed: 1.
An electric arc welding apparatus comprising at least a first consumable electrode and a second consumable electrode movable in unison along a welding path between the edges of two adjacent, mutually grounded plates, a first power supply for passing a first welding current at a first low frequency between said first electrode and said plates, a second power supply for passing a second welding current at a second low frequency between said second electrode and said plates, each of said power supplies including a three phase voltage input operated at line frequency, a rectifier to convert said input voltage to a DC voltage link and a high frequency switching type inverter converting said DC voltage link to a high frequency AC current, an output rectifier circuit to provide a positive voltage terminal and a negative voltage terminal, and an output switching network operated at a given low frequency for directing a pulsating welding current at said given low frequency from said terminals across one of said electrodes and said plates, and a circuit for independently adjusting said given low frequency so the value of said first low frequency of said first power supply is different from said second low frequency of said second power supply.
2.
An electric arc welding apparatus as defined in claim 1 wherein said first and second low frequencies are in the general range of 5 to 200 Hz.
3.
An electric arc welding apparatus as defined in claim 2 wherein said consumable electrodes are advance welding wires.
4.
An electric arc welding apparatus as defined in claim 2 wherein said three phase voltage input for each of said first and second power supplies is the same power source.
5.
An electric arc welding apparatus as defined in claim 2 wherein said means for adjusting said given low frequency of at least one of said first and second power supplies includes means for causing said given low frequency to vary as a function of time
|
|
Gutter-related 
