Did You Know...
...that Charles Goodyear performed some of his experiments on rubber while in debtor's prison? He was there so often he referred to it as his "hotel". Chronically in debt because of poor business sense and ill health, Goodyear depended on the generosity of friends and family. Even after he unlocked the secret to vulcanizing rubber, he was unable to improve his financial situation. When he died, his estate was $200,000 in debt.
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| Number | Title | Issue Date |
| 5764500 | Switching power supply A switching power supply (30) uses a transformer 37 having a first primary winding (38A) and a second primary winding (38B) wrapped around the same core (52, 53) but wrapped around opposite sides of the core (52, 53). One of the ends from each of a pair o... | 06/09/1998 |
| 5612664 | Electronic circuit An electronic circuit in which resistors R0 . . . Rn+m are coupled in series with fusible cut-outs Q0 . . . Qn+m and in which at least one fusible cut-out Qn+1 . . . Qn+m is bridged by an a... | 03/18/1997 |
| 4858095 | Magnetron drive apparatus In a magnetron drive apparatus a high frequency voltage converted and outputted by a frequency converter is inputted to a primary winding of a transformer and a high voltage power outputted from a secondary winding of the transformer is rectified and supp... | 08/15/1989 |
| 4841428 | Non-saturating magnetic amplifier controller A magnetic amplifier including a magnetic core having a primary leg, a secondary leg, and a control leg. A primary winding is wound about the primary leg of the magnetic core for generating a non-saturating magnetic AC flux in the magnetic core, and a sec... | 06/20/1989 |
| 4837497 | Variable transformer, reactor and method of their control A variable transformer, reactor having a core combining at least two complete core elements wiht a common yoke; primary winding divided into two independently fed sets of phase coils wound in opposite direction, arranged on symmetrical legs of core elemen... | 06/06/1989 |
| 4766365 | Self-regulated transformer-inductor with air gaps The transformer comprises a three-limbed magnetic core having two outer limbs each defining a central air gap. Two windings, an alternating current one and a direct current one, are wound around each outer limb. Primary and secondary windings are disposed... | 08/23/1988 |
| 4620144 | Self-controlled variable inductor with air gaps An electric power apparatus, namely a variable inductor comprising a magnetic core provided with a center limb and two outer limbs all having first and second ends. The first ends are interconnected through a first common point of the magnetic core, and t... | 10/28/1986 |
| 4600872 | Apparatus for variable speed drive of an induction motor from a fixed frequency AC source A control system for driving a variable speed AC motor employing a fixed frequency AC power source, combines pulses representative of a desired slip frequency with pulses of a frequency proportional to the speed of the motor. The combined pulses are emplo... | 07/15/1986 |
| 4445082 | Variable ratio transformer and static balance compensator Variable ratio transformer constructed around a control transformer comprising: two closed magnetic circuits each constructed around a ferromagnetic core. An alternating current magnetic field circulates in the first core and a direct current magnetic fie... | 04/24/1984 |
| 4378522 | Adjustable current source An adjustable current source comprises a choke (1) and a capacitor (2) whose reactive impedances are equal at the frequency of a variable voltage source (3), as well as a load current matching and adjusting unit made as a magnetic amplifier (4). Some outp... | 03/29/1983 |
| 4339792 | Voltage regulator using saturable transformer A voltage regulator using a saturable transformer comprises a transformer having a primary and secondary windings, an AC power source for supplying the primary winding a fluctuating alternating current, and a rectifier connected to the secondary winding f... | 07/13/1982 |
| 4328458 | Variable leakage transformer and control circuit therefore A variable leakage transformer having a closed main magnetic path and a closed submagnetic path having a leg common with said main magnetic path. A primary winding is wound on said common leg, and a secondary winding is wound on said main magnetic path. T... | 05/04/1982 |
| 4138636 | Voltage regulating transformer having EI laminations and two center legs of different reluctance A shell-type voltage regulating transformer includes a magnetic core comprising a stack of modified EI laminations having a center leg forming two sections. One of the center leg sections defines a low reluctance magnetically saturable path while the othe... | 02/06/1979 |
