Marine shift speed equalizer
US4986776A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 20, 1989 |
| Grant date | Jan 22, 1991 |
| Priority date | — |
| Expiry date | Jun 20, 2009 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A shift speed equalizer is provided in a marine transmission in a marine drive subject to a decrease in engine speed upon shifting from neutral to a forward or reverse gear due to a high propeller pitch or the like, such as in bass boat applications, and subject to an increase in engine speed upon shifting back to neutral. The shift from neutral to forward or reverse is sensed, and engine speed is increased in response thereto, to compensate the decrease in engine speed due to shifting. The return shift back to neutral is sensed, and engine speed is decreased in response thereto, to compensate the increase in engine speed due to shifting. Engine speed is increased by advancing engine spark ignition timing, and engine speed is decreased by retarding or returning engine ignition timing to its initial setting. Particular methodology and structure is disclosed, including modifications to an existing shift plate and to an existing guide block to enable the noted functions, and including the addition of an auxiliary circuit to existing ignition circuitry enabling the desired altering of engine ignition timing to keep engine speed from dropping when shifting into forward or reverse.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.