Hardware control for prevention of dangerous restart in a power tool
US10833503B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 9, 2018 |
| Grant date | Nov 10, 2020 |
| Priority date | — |
| Expiry date | Oct 9, 2038 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH02P29/10
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A power tool including a power supply interface, a motor control circuit configured to regulate supply of power from the power supply interface to a motor, and an input unit actuatable by a user. A no-volt prevention circuit receives a first voltage signal from the power supply interface and a second voltage signal from the input unit. The no-volt protection circuit includes a main semiconductor switch arranged on a current path from the power supply interface to at least one component of the motor control circuit, and a resistor-capacitor circuit to turn the main semiconductor switch ON when the input unit is actuated after the power supply interface is coupled to the power supply, but not when the input unit is actuated before to the power supply interface is coupled to the power supply.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.