System for controlling energy output of combustion-powered, fastener-driving tool
US5592580A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 10, 1994 |
| Grant date | Jan 7, 1997 |
| Priority date | — |
| Expiry date | Nov 10, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S388/937
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
A system for controlling the energy output of a combustion-powered, fastener-driving tool in which a fan is arranged to produce turbulence in a combustion chamber when the fan is driven, in which a direct current motor is arranged to drive the fan when a driving voltage is applied across the motor, and in which a battery provides a battery voltage not less than the driving voltage. A voltage divider includes a settable resistance, either a potentiometer or two parallel, fixed resistances that can be alternatively selected, and is used to provide a setpoint voltage. A comparator, an inverter, and a transistor switch are arranged to sample a voltage proportional to the rotational speed of the fan, to compare the sampled voltage to the setpoint voltage, to apply the driving voltage across the motor if the sampled voltage is less than the setpoint voltage, and to remove the driving voltage from across the motor if the sampled voltage is not less than the setpoint voltage. The voltage divider also includes a permanently grounded resistance, two selectively groundable resistances, and two photoelectric switches, each including a phototransmissive diode and a photoreceptive transistor and…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.