摘要:
A valve timing control system for an internal combustion engine includes a housing having and a cover member mounted thereto, a phase adjusting mechanism accommodated in the housing to hydraulically change the rotation phase of a crankshaft and a camshaft, a supply/discharge rod arranged through a through hole of the cover member and connected to the phase adjusting mechanism, a seal ring engaged with the supply/discharge rod to hermetically seal a clearance between the supply/discharge rod and the phase adjusting mechanism, a taper surface formed on the periphery of the through hole to increase the diameter of the through hole toward the outside of the housing, and a protrusion formed with the cover member in a radially inside area thereof to protrude in the axial direction of the system, wherein the through hole is formed at the protrusion.
摘要:
A plurality of advanced angle chamber oil paths communicated to advanced angle hydraulic chambers and a plurality of retarded angle chamber oil paths communicated to retarded angle hydraulic chambers according to a change in rotating angle of a cam shaft are provided. The plurality of advanced angle chamber oil paths and the plurality of retarded angle chamber oil paths, respectively, are switched between communication and cut-off according to a rotating angle of the cam shaft. When torque in the direction of advanced angle acts in an advanced angle mode for phase shifting in the direction of advanced angle, the advanced angle hydraulic chambers are caused to communicate to a hydraulic power source and the retarded angle hydraulic chambers are caused to communicate to a drain. Also, at high speed of an engine, in the advanced angle mode, shut-off valves in the advanced angle chamber oil paths and the retarded angle chamber oil paths are opened so that hydraulic pressure is communicated from the hydraulic power source to the advanced angle chambers at all times in the same manner as in the related art.
摘要:
In a variable valve timing controlling apparatus for an internal combustion engine having an engine valve, the controlling apparatus having:a rotational body rotated in synchronization with an engine crankshaft;a camshaft, one end thereof being inserted into the rotational body and the camshaft including a cam located on an outer periphery of the camshaft to open the engine valve against a spring force exerted by a valve spring of the engine valve; a phase changing device interposed between the rotational body and the one end of the camshaft to hydraulically vary a relative rotational phase between the rotational body and the camshaft; and a hydraulic pressure circuit to relatively supply and drain a hydraulic pressure to and from at least one retardation angle hydraulic pressure chamber and at least one advance angle hydraulic pressure chamber, each hydraulic pressure chamber being formed within the rotational body to drive the cam phase changing device, an interrupting mechanism is provided to interrupt a hydraulic pressure passage of the hydraulic pressure circuit to supply the hydraulic pressure to at least one of the advance angle and retardation angle hydraulic pressure chambers for a time duration which corresponds to a torque peak region of a rotation variation torque developed on the camshaft.
摘要:
A variable displacement pump including a chamber volume varying mechanism including a moveable member, a first biasing member always biasing the moveable member in such a direction as to increase volumes of the working fluid chambers, and a second biasing member that is disposed with a set load and applies a biasing force to the moveable member in such a direction as to increase the volumes of the working fluid chambers when the moveable member is displaced against a biasing force of the first biasing member by a predetermined amount or more. The biasing force of the first biasing member is set such that before the moveable member is displaced against the biasing force of the first biasing member, the valve timing control device is shifted to a release state in which an open-and-closure timing of an engine valve is variably controlled.
摘要:
A plurality of advanced angle chamber oil paths communicated to advanced angle hydraulic chambers and a plurality of retarded angle chamber oil paths communicated to retarded angle hydraulic chambers according to a change in rotating angle of a cam shaft are provided. The plurality of advanced angle chamber oil paths and the plurality of retarded angle chamber oil paths, respectively, are switched between communication and cut-off according to a rotating angle of the cam shaft. When torque in the direction of advanced angle acts in an advanced angle mode for phase shifting in the direction of advanced angle, the advanced angle hydraulic chambers are caused to communicate to a hydraulic power source and the retarded angle hydraulic chambers are caused to communicate to a drain. Also, at high speed of an engine, in the advanced angle mode, shut-off valves in the advanced angle chamber oil paths and the retarded angle chamber oil paths are opened so that hydraulic pressure is communicated from the hydraulic power source to the advanced angle chambers at all times in the same manner as in the related art.
摘要:
A valve timing control device comprises a drive rotation member driven by a crankshaft of an internal combustion engine; a driven rotation member fixed to a camshaft that actuates engine valves to open and close, the drive rotation member and driven rotation member being coaxially arranged to make a relative rotation therebetween; a phase varying mechanism that rotates the driven rotation member relative to the drive rotation member within a given angle, the phase varying mechanism being able to cause the driven rotation member to take the most-retarded phase position, the most-advanced phase position and a middle phase position defined between the most-retarded phase position and the most-advanced phase position; and a position keeping mechanism that is able to keep the driven rotation member at least the most-retarded phase position and the middle phase position at the time of starting the engine, and is able to select one of the most-retarded phase position and the middle phase position in accordance with an operation condition of the engine.
摘要:
In a hydraulic pressure circuit including an introduction section through which oil is introduced, a main passage section installed at a downstream side of the introduction section to be communicated with a supply section through which oil is supplied to each of slide sections of an internal combustion engine, a branch passage branched from the main passage section to supply oil to a hydraulic pressure actuator, and a control valve having a valve body which is moved in accordance with a pressure of an upstream side thereof, and a variable capacitance pump configured to drain oil to the introduction section, the variable capacitance pump is configured to vary a drained flow quantity in accordance with the drained pressure of oil and a pressure under which the oil drained flow quantity is started to be varied is higher than a pressure under which the valve body is started to move.
摘要:
In a hydraulic pressure circuit including an introduction section through which oil is introduced, a main passage section installed at a downstream side of the introduction section to be communicated with a supply section through which oil is supplied to each of slide sections of an internal combustion engine, a branch passage branched from the main passage section to supply oil to a hydraulic pressure actuator, and a control valve having a valve body which is moved in accordance with a pressure of an upstream side thereof, and a variable capacitance pump configured to drain oil to the introduction section, the variable capacitance pump is configured to vary a drained flow quantity in accordance with the drained pressure of oil and a pressure under which the oil drained flow quantity is started to be varied is higher than a pressure under which the valve body is started to move.
摘要:
A variable displacement pump including a chamber volume varying mechanism including a moveable member, a first biasing member always biasing the moveable member in such a direction as to increase volumes of the working fluid chambers, and a second biasing member that is disposed with a set load and applies a biasing force to the moveable member in such a direction as to increase the volumes of the working fluid chambers when the moveable member is displaced against a biasing force of the first biasing member by a predetermined amount or more. The biasing force of the first biasing member is set such that before the moveable member is displaced against the biasing force of the first biasing member, the valve timing control device is shifted to a release state in which an open-and-closure timing of an engine valve is variably controlled.
摘要:
A parallel guide portion as an integral structure of a sprocket and a vane, as well as a slant guide portion, are arranged alternately on the same circumference, with circumferential gaps being formed between said guide portion and the parallel guide portion, said guide portion having a shape such that the circumferential gaps become smaller in one axial direction of a cam shaft. Wedge members are disposed in the circumferential gaps respectively and are moved in one axial direction to fill up the circumferential gaps, thereby fixing the phase between the sprocket and the vane into a locked state. The wedge angle of each wedge member is set sufficiently small and, by utilizing varying torques acting on the cam shaft, said members are each moved and locked in one axial direction with a spring. Said members are actuated in an opposite axial direction with oil pressure to release the locked state, thereby permitting a phase angle control. By utilizing a varying torque acting on the cam shaft, the phase of the cam shaft is returned for itself to an intermediate position and is locked without looseness.