Protective circuit for an electronic switching amplifier in series with an electromagnet
Abstract
Abstract A protective circuit for an electronic switching amplifier is controlled by an operating switch, the amplifier serving to turn on an electromagnet with timed pulses during its operating interval. The electromagnet may electromagnetically actuate positioning and actuating elements on sewing machines and the like, with the timed pulses. A cutoff voltage limiting circuit is connected on one side between the electromagnet and the switching amplifier. A free-running diode is connected in parallel with the electromagnet through an electronic switch as an additional cutoff voltage limiting circuit. The electronic switch is caused to conduct by the switching amplifier during the operating interval, at least during the decay of the timing pulses. The electronic switch is blocked when the operating interval is terminated by the operating switch. The cutoff voltage limiting circuit is designed to conduct when electronic switch is blocked.
Inventors
- 👤 Alfred Heidt
Bibliographic Details
Claims Analysis
Total Claims: 4References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-09-03 | 1983-03-05 | 1983-09-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-09-03 | 1987-03-05 | 1987-09-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-09-03 | 1991-03-05 | 1991-09-04 | $7700.00 | Window Closed / Lapsed |