| 5954985 |
Matching apparatus for connecting high frequency solid state electrical power |
Paul F. Scott, Michael Turzhitsky, Thomas G. Lee |
1999-09-21 |
| 5902506 |
Matching apparatus for connecting high frequency solid state electrical power generator to a load |
Paul F. Scott, Michael Turzhitsky, Thomas G. Lee |
1999-05-11 |
| 5814791 |
Electrical apparatus with a variable circuit protection device |
— |
1998-09-29 |
| 5571437 |
Induction welding of tubing with multiple induction coils |
— |
1996-11-05 |
| 4916278 |
Severing metal strip with high frequency electrical current |
Humfrey N. Udall |
1990-04-10 |
| 4906805 |
Method and apparatus for high frequency electrical cast welding and surface hardening |
— |
1990-03-06 |
| 4845326 |
Apparatus and method for electrically butt welding of skelp edge faces which have been preheated |
Humfrey N. Udall, Robert R. Harriau |
1989-07-04 |
| 4508949 |
Method and apparatus for welding tapered metal poles |
— |
1985-04-02 |
| 4362921 |
Welding of fins to tubing |
— |
1982-12-07 |
| 4326583 |
Heat exchanger panels |
— |
1982-04-27 |
| 4287947 |
Solar panel elements and method of manufacture thereof |
Edgar D. Oppenheimer, Humfrey N. Udall |
1981-09-08 |
| 4278868 |
Methods and apparatus for heating metal parts with magnetically driven travelling electric arc |
Humfrey N. Udall |
1981-07-14 |
| 4241284 |
Electrical contact apparatus for high frequency welding |
Humfrey N. Udall |
1980-12-23 |
| 4234776 |
Method of producing areas of alloy metal on a metal part using electric currents |
Humfrey N. Udall |
1980-11-18 |
| 4219722 |
Methods and apparatus for heating metal parts with magnetically driven travelling electric arc |
Humfrey N. Udall |
1980-08-26 |
| 4215259 |
Surface hardening of metals using electric currents |
Humfrey N. Udall |
1980-07-29 |
| 4197441 |
High frequency induction welding with return current paths on surfaces to be heated |
— |
1980-04-08 |
| 4192984 |
Embedment of hard particles in a metal surface |
— |
1980-03-11 |