Hydraulic valve lift device
US4408580A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Aug 15, 1980 |
| Grant date | Oct 11, 1983 |
| Priority date | — |
| Expiry date | Aug 15, 2000 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF01L1/245
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A hydraulic valve lift device for internal combustion engines includes a lifter having therein an oil pressure chamber for introduction of oil and slidably disposed in a cylindrical bore of a housing with one end thereof engaged by a cam on a cam shaft, and a plunger slidably disposed in the lifter for opening and closing an intake or exhaust valve of which a valve lift is variable depending upon the rotational speed of the cam by discharging oil from the oil pressure chamber through a throttling port. A braking chamber is defined by a flange portion of the plunger and the cylindrical bore, and is communicated through a slit with a oil feed chamber adapted to allow oil to flow thereinto. A relief valve is provided for communicating with the braking chamber to control its oil pressure below a set value. A control device is provided for controlling the relief valve depending upon an output of a detector such that the set force of the valve corresponds with a desired value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.