Electric power tool and method of controlling rotational speed of motor in electric power tool
US10780563B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 4, 2017 |
| Grant date | Sep 22, 2020 |
| Priority date | — |
| Expiry date | Apr 3, 2038 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB25D2250/265
- WIPO fieldMachine tools
- WIPO sectorMechanical engineering
Abstract
An electric power tool according to one aspect of the present disclosure includes a main body, a motor, a tool holder configured to hold a tool bit, a hammer, a motion converter, a rotation transmitter, a first load detector, a second load detector, and a motor controller. The first load detector detects, based on information indicating a drive state of the motor, a load imposed from a work piece to the tool bit. The second load detector detects, based on information indicating a behavior of the main body, a load imposed from the work piece to the tool bit. The motor controller sets an upper limit of rotational speed of the motor to a predetermined no-load rotational speed in response to no-load on the tool bit being detected by both the first load detector and the second load detector.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.