Torque limiting arrangement in an I.C. engine
US4633832A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 18, 1986 |
| Grant date | Jan 6, 1987 |
| Priority date | — |
| Expiry date | Feb 18, 2006 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02P9/005
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
In engine-powered machines (motor cutting saw, motor chain saw) with a centrifugal clutch a wearing on the clutch and belt takes place by a high load at an r.p.m. around or above the skidding r.p.m. of the centrifugal clutch. A step for reducing the said wearing can--according to the invention--be taken by limiting the driving torque of the engine in the above-said r.p.m. interval. The invention means that the cutting machine/motor saw is provided with electronic equipment counting r.p.m. and then controlling the ignition system so that the torque of the engine is lowered in a predetermined interval. In a cutting machine ignition is allowed in, for example, every third revolution within the interval 3000-6000 r.p.m. The working mode can also be widened so that the time difference between several revolutions is detected. It is then possible to indicate when the cutting machine/motor saw is in acceleration and thus refrain from reduction of the torque of the engine in order to make the machine rapidly return to a proper r.p.m. after a reduction thereof.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.