Back to results
US 2013/0340694 A1Published application
Variably operated valve system for internal combustion engine
AssigneeHitachi Automotive Systems, Ltd.
InventorMakoto NAKAMURA
Life of this patent
Estimating the term…
Abstract
A variably operated valve system for an internal combustion engine, a valve stop mechanism (11) makes at least one of a pair of fulcrum members lost motion to stop open-and-closure drives for one of two engine valves per cylinder and a stop of open-and-closure drives for the one of the engine valves is inhibited, in a case where a lost motion quantity of the valve stop mechanism exceeds a predetermined value (M3).
Claims20
A variably operated valve system comprising:
- a drive shaft to which a rotation driving force is transmitted from an engine crankshaft and on an outer periphery of which drive cams are disposed;
- two swing cams that operate two engine valves per engine cylinder to open against spring forces of respective valve springs;
- a transmission mechanism that converts rotation motions of the drive cams into swing motions and transmits the converted swing motions to the respective swing cams;
- a pair of swing arms interposed between the respective swing cams and the respective engine valves to operate the respective engine valves to open or close;
- a pair of fulcrum members each of which provides a swing fulcrum of each of the swing arms;
- a control mechanism that varies a posture of the transmission mechanism to variably control a lift quantity of each of the engine valves;
- a valve stop mechanism that makes at least one of the pair of fulcrum members lost motion to stop open-and-closure drives for one of the two engine valves;
- and
- valve stop inhibit means for inhibiting a stop of open-and-closure drives for the one of the engine valves, in a case where a lost motion quantity of the valve stop mechanism exceeds a predetermined value.
6 more elements
A variably operated valve system for an internal combustion engine, comprising:
- drive cams to which a rotational force is transmitted from a crankshaft;
- engine valves, two of the engine valves being mounted in each of engine cylinders and each engine valve being biased toward a valve closure direction by means of a spring force of a corresponding one of valve springs;
- swing cams that make the respective engine valves open operation against spring forces of valve springs;
- a transmission mechanism that converts rotation motions of the drive cams into swing motions and transmits the converted swing motions to the swing cams;
- a control mechanism that varies a posture of the transmission mechanism to variably control a lift quantity of each of the engine valves;
- a pair of operational members that swing in accordance with the swing motions of the swing cams to operate the respective engine valves to open or close;
- a valve stop mechanism that absorbs a swing quantity of one of the pair of operational members to stop open-and-closure operations of one of the two engine valves;
- and
- valve stop inhibiting means for inhibiting an absorption of a swing motion of the valve stop mechanism in a case where the swing quantity of each of the pair of the operational members exceeds a predetermined quantity.
6 more elements
A variably operated valve system for an internal combustion engine, comprising:
- a drive cam rotationally driven through a crankshaft;
- a pair of engine valves, each engine valve being biased toward a closure direction by means of a spring force of a valve spring;
- a pair of swing cams that swing to drive the pair of engine valves via a pair of operational members;
- a transmission mechanism that converts a rotation motion of the drive cam into a swing motion and transmits the converted swing motion to the pair of swing cams;
- a control mechanism that varies a posture of the transmission mechanism to vary operation characteristics of the pair of the engine valves;
- and
- a valve stop mechanism disposed on at least one of the pair of operational members to make a lost motion to stop a drive of one of the pair of engine valves, wherein, in a case where a valve lift quantity of one of the pair of engine valves exceeds a predetermined value, an operation of a valve stop through the valve stop mechanism is inhibited.
4 more elements
Dependencies are inferred from the claim text.