Abstract:
An engine generator has an opening and closing mechanism including: a control shaft provided to a valve shaft of a choke valve to be rotatable relative thereto within a predetermined angular range; an urging member urging the valve shaft relative to the control shaft in a direction in which an opening degree of the choke valve decreases; a restriction mechanism that sets a minimum opening degree of the choke valve by restricting a range of rotation of the control shaft; a choke operating portion which, upon operation, drives the restriction mechanism in a direction in which the minimum opening degree of the choke valve decreases; and a negative pressure mechanism driven by a negative pressure generated during an operation of the engine to cause the control shaft to rotate to increase the minimum opening degree of the choke valve within the range of rotation restricted by the restriction mechanism.
Abstract:
In a variably operated valve system for a multi-cylinder internal combustion engine and a control apparatus for the variably operated valve system, a first valve stop mechanism is configured to switch between a valve operation state in which one of a pair of intake valves from among the pair of intake valves of a part of a plurality of cylinders is operated to be open or closed and a valve stopped state in which the valve open or closure operation of the one of the intake valves is stopped, a second valve stop mechanism is configured to switch between the valve operation state in which the other of the pair of intake valves from among the pair of intake valves of the part of the cylinders is operated to be open or closed and the valve stopped state in which the valve open or closure operation is stopped.
Abstract:
Provided is a variable valve device for an internal combustion engine, capable of improving engine characteristics by increasing the maximum valve lift of an intake valve to a large valve lift while preventing excessive lost motion operation of lost motion mechanisms. The variable valve device includes intake- and exhaust-side swing arms that pivot to open and close intake valves (3a, 3b) and exhaust valves (61a, 61b) in two cylinders #1, #2, intake- and exhaust-side hydraulic lash adjusters (10a, 10b, 65a, 65b) that serve as pivot points of the respective swing arms, a variable valve system that continuously varies valve lift characteristics of the intake valves and lost motion mechanisms (11) that stop opening and closing of the intake exhaust valves by lost motion of the intake- and exhaust-side hydraulic lash adjusters on the cylinder #1. The maximum valve lifts of the intake valves are set larger than valve lifts of the exhaust valves. The minimum valve lifts of the intake valves are set smaller than the valve lifts of the exhaust valves.
Abstract:
A valve control apparatus includes first and second engine valves; a first drive cam configured to rotate integrally with the drive shaft; a second drive cam provided on the drive shaft and configured to rotate integrally with the drive shaft; a swing cam configured to swing; a transmission mechanism configured to convert a rotation of the first drive cam into a swinging force and to transmit the swinging force to the swing cam; a first swing arm configured to open the first engine valve by a swing of the swing cam; a second swing arm configured to open the second engine valve by a rotation of the second drive cam; a control mechanism configured to vary a swing amount of the swing cam by varying an attitude of the transmission mechanism; and a connection changeover mechanism configured to connect and disconnect the first swing arm with/from the second swing arm.
Abstract:
A variably operated valve system includes: a planar section cut out an outer peripheral surface of a control shaft in order for a linkage member to be grasped from an axial direction of the control shaft; a bolt hole drilled along a diameter direction of the control shaft via an oil passage from the planar section and having a female screw formed at a position of the control shaft which is an opposite side to the planar section; and a limitation section having a convexity section disposed on either one of the linkage member and the planar section and a recess section disposed on the other of the linkage member and the planar section to be fitted into the convexity section, a fixture bolt being screwed and tightened to the bolt hole via a bolt inserting hole of the linkage member to fix the linkage member to the control shaft.
Abstract:
An engine with intake and exhaust valves that may be controlled with a circular cam lobe is provided. The rotating axis of the circular cam lobe is offset from the physical center of the cam lobe. This permits the cam lobe to impart a reciprocal opening and closing of the valve. To maintain the valve in the closed position, the interconnection between the cam lobe and the valve 12 may have a spring which is compressed to allow the valve to remain closed for a set duration of time while the cam lobe continues to rotate.
Abstract:
A valve operating device for an internal combustion engine enabling both valve timing and valve lift characteristic to be varied depending on engine operating conditions includes intake and exhaust camshafts, an eccentric cam fixed to a first one of the intake and exhaust camshafts so that an axis of the eccentric cam is eccentric to an axis of the first camshaft. A rockable cam is supported on the first camshaft so that the rockable cam rotates or oscillates about the axis of the first camshaft. A rocker arm is oscillatingly supported on an outer periphery of the eccentric cam so that a center of an oscillating motion of the rocker arm revolves around the axis of the first camshaft. Also provided is a control shaft variably controlling the center of the oscillating motion of the rocker arm.
Abstract:
The invention relates to a valve mechanism for controlling a disc valve (1) of an internal combustion engine and comprises a control shaft (2) which is driven by the engine crankshaft, and a push rod (3) which is driven by the control shaft (2) and which for the purpose of transmitting reciprocating movement is connected to one arm (14) of a two-arm rocker (4) which is pivotable about a rocker shaft (15) and the other arm (16) of which rocker transmits these movements to the valve (1). The valve mechanism according to the invention is characterized in that the control shaft (2) is intended to act upon the push rod (3) in both directions of movement thereof; in that the first arm (14) of the rocker (4) extends essentially at right angles to the push rod (3) and the second arm (16) of the rocker extends essentially parallel with the longitudinal geometric axis of the valve (1); and in that a lifting arm (5) is provided for transferring rocker movement to the valve (1). The other arm (16) of the rocker (4) is provided with activating means (18) for coaction with the lifting arm (5), one end of which is pivotally mounted on a lifting arm shaft (19) and the other end of which is provided with means for activating the valve (1). The lifting arm surface (20) which co-acts with the second arm (16) of the rocker (4) is profiled in a manner to achieve the desired pattern of movement of the second end of the lifting arm (5) in response to movement of the rocker (4).