Abstract:
An air injection system for an engine includes an exhaust flange formed in a cylinder head integrated with an exhaust manifold, wherein the exhaust manifold is coupled to the exhaust flange, an air injection nozzle provided on the cylinder head or the exhaust manifold, a valve configured to control air supplied to the air injection nozzle, and a controller configured to control the valve, wherein the controller is configured to control the valve and inject air through the air injection nozzle when an exhaust-gas temperature reaches a predetermined combustion temperature in an initial start stage of the engine.
Abstract:
A method for detecting a damaged-bearing in an engine using a vibration signal may include: separating, by a controller, a vibration signal of the engine detected by a vibration detecting device installed on one side of the engine of a vehicle into a vibration signal caused by combustion knocking and a vibration signal generated in a bearing, extracting a signal in a predetermined natural frequency band from the vibration signal generated in the bearing using a band-pass filter, and processing the extracted signal to a quantified bearing signal using the controller, and comparing the quantified bearing signal with a preset damaged-bearing criterion using the controller to determine whether the quantified bearing signal is equal to or higher than the preset damaged-bearing criterion to determine a damage to the bearing.
Abstract:
An engine system may include a main intake line, a supplementary intake line branched from the main intake line and joined to the main intake line, an intake bypass valve mounted to the main intake line, a main exhaust line mounted to an exhaust manifold, a supplementary exhaust line branched from the exhaust manifold and joined to the main exhaust line, an exhaust bypass valve mounted to the main exhaust line and selectively opening the main exhaust line, a turbocharger disposed adjacent to the supplementary exhaust line and operated by exhaust gas passing through the supplementary exhaust line, and a control unit for controlling the intake bypass valve and the exhaust bypass valve depending on an operation condition, wherein the exhaust gas is re-circulated from an upstream side of the exhaust bypass valve to the main intake line passing through an EGR (Exhaust Gas Recirculation) cooler and an EGR valve.
Abstract:
An engine system may include a first intake line connected to an intake manifold and supplying the intake manifold disposed on a cylinder block with outside air, an intake bypass valve disposed on the first intake line, a second intake line that bypasses the first intake bypass valve to the intake manifold, a first exhaust line through which exhaust gas flows from an exhaust manifold disposed on the cylinder block, an exhaust bypass valve disposed on the first exhaust line, a second exhaust line connected to the exhaust manifold and bypasses the exhaust bypass valve, a turbo charger disposed between the second intake line and the second exhaust line and operated by exhaust gas passing the second exhaust line to pump intake air flowing the second intake line, and a control portion that controls the intake bypass valve and the exhaust bypass valve depending on a driving condition.
Abstract:
An engine having a variable valve timing device and a variable tumble device, may include the variable valve timing device advancing or delaying a rotation of an intake camshaft or an exhaust camshaft, an intake valve or an exhaust valve configured to be operated by the intake camshaft or the exhaust camshaft respectively to open and close an intake port or an exhaust port, and the variable tumble device that may be disposed on an upstream side of the intake valve in the intake port and changes a flow of a gas being suck to form a tumble in a combustion chamber.
Abstract:
A secondary air injection system supplying some of air introduced into an intake manifold to an exhaust manifold may include: an electric supercharger compressing air introduced through an air duct; throttle valves installed at an upstream of the intake manifold and controlling the amount of air introduced into the intake manifold by controlling the amount of air passing through the electric supercharger; secondary air valves installed on branching paths branched from intake, lines that link the electric supercharger and the throttle vales and controlling the amount of air for secondary air injection; and an injector that post-combusts exhaust gas discharged from an engine by injecting secondary air passing through the secondary air valve to a runner of the manifold.