Abstract: A type III rocker arm assembly operable in a first mode and a second mode based on rotation of a cam shaft includes a rocker shaft and a first rocker arm assembly. The first rocker arm assembly receives the rocker shaft and is configured to rotate around the rocker shaft in the first mode based on engagement with the first cam lobe. The first rocker arm assembly collectively comprises a valve side rocker arm, a cam side rocker arm and a latch pin. The valve side rocker arm defines a valve side rocker arm bore. The cam side rocker arm defines a cam side rocker arm bore. The latch pin assembly is received by the valve and cam side rocker arm bores and selectively couples the valve side rocker arm and the cam side rocker arm for concurrent movement in the first mode.

Abstract: A decompression shaft (56) of a decompression device (50) includes an engagement pin (53) that is guided by a guide groove (51a) formed in a decompression weight (51), a decompression cam (54) that is provided on one cam surface of an intake valve cam (25c) and an exhaust valve cam (25b) so as to advance and retreat, and a connection portion (55) that connects the engagement pin (53) and the decompression cam (54). The decompression weight (51) is formed with a rotation restricting groove (51e) that restricts rotation of the decompression shaft (56) when a force acts in a direction in which the decompression cam (54) moves on the decompression shaft (56) from an advanced position to a retracted position when an engine (E) is stopped and that is continuous with the guide groove (51a).

Abstract: A throttle tube assembly including a throttle tube, a throttle body, a bearing, and a stop collar. The throttle tube extends along a central axis from a proximal most end to a distal most end, the throttle including a lumen extending through the throttle tube. The throttle body is connected to the throttle tube, at the proximal end of the throttle tube, the throttle body having a bearing seat aligned along the central axis with the throttle body. The bearing being disposed in the bearing seat and axially aligned with the throttle body and partially axially aligned with the throttle tube. The stop collar is fixed to the throttle body configured and arranged to actuate a throttle by wire system.

Abstract: A twist grip throttle assembly and weed trimmer utilizing the same are described herein. The weed trimmer has a power head on an upper end of a drive shaft assembly. The power head has a power provider, such as a gas powered motor. A base assembly with a cutter head for receiving wrapped cord is on a lower end of the drive shaft assembly. A throttle activator includes a tubular member rotationally mounted on the drive shaft assembly. The tubular member defines a gripping area. Twisting rotation of the throttle activator adjusts an amount of power produced by said power provider.

Abstract: A valve timing controller for controlling a valve timing of an intake valve that opens and closes by a rotation of a camshaft to which a power is supplied from a crankshaft of an internal-combustion engine. The valve timing controller includes a phase changer changing a rotation phase for an adjustment of the valve timing; an electric actuator driving the phase changer; and a control section controlling an operation of the electric actuator, in which the control section performs a start time control process, controlling the valve timing to a rotation starter phase retarded from a preset reference phase at a start of crankshaft rotation, and controlling the valve timing to an engine started phase advanced therefrom after a passing of a top dead center in a first compression process by a piston in a cylinder after the start of crankshaft rotation and before completion of engine start.

Abstract: A control device for an internal combustion engine is configured to: execute a first decompression operating processing such that a decompression operating state is selected in a first engine speed region that passes in the course of engine stop; execute a decompression stop processing such that a switching from the decompression operating state to a decompression stop state is performed in the course of the engine stop after passage of the first engine speed region; when a temperature correlation value is greater than or equal to a threshold value upon an engine start-up request, execute a second decompression operating processing such that the decompression operating state is selected in a second engine speed region that passes in the course of engine start-up before the start of fuel injection. When the temperature correlation value is smaller than the threshold value, the second decompression operating processing is not executed.

Abstract: A method for starting an internal combustion engine by a compressed air starting system, in which in a first starting sequence the engagement of the starter is brought about by compressed air, a decompression valve for relieving the cylinder working space is acted on in the opening direction, and starting of the internal combustion engine is initiated by pulsed compressed air being applied to the starter. In a second starting sequence the decompression valve is acted on in the closing direction, and constant compressed air is applied to the starter.

Abstract: An engine brake device is disclosed. The engine brake device includes at least one intake camshaft which includes at least one intake cam group having at least one firing cam and at least one braking cam, at least one intake cam follower that is assigned to the firing cam and is provided for actuating at least one intake valve in a firing mode, at least one braking intake cam follower that is assigned to the braking cam and is provided for actuating the at least one intake valve in a braking mode, and a switchover device that is assigned to the intake camshaft and is provided for the purpose of translating a torque of the intake camshaft into a force for switching between the firing mode and the braking mode.

Abstract: A decompression pin is inserted into a swing range of an end portion of a rocker arm, on a side which is supported by a lash adjuster, when the rocker arm has been inclined toward a direction in which a valve is opened. The decompression pin comes into contact with the end portion of the rocker arm when the rocker arm is inclined toward a direction in which the valve is closed, and thereby restricts the rocker arm from returning to a position at which the valve is completely closed, and the valve becomes in a slightly opened state even in a compression stroke.

Abstract: The invention relates to a method for starting an internal combustion engine for a motor vehicle, said internal combustion engine having at least two cylinders, a valve drive with at least one inlet valve and at least one outlet valve for each of the cylinders, wherein at least the closing times of the inlet valves can be variably adjusted, and a direct injection system, in particular a gasoline direct injection system, the starting process being initiated by a direct injection and ignition in one of the cylinders. During a starting process, the closing time of at least one inlet valve differs from at least one of the other cylinders dependent on at least one current state value.

Abstract: A camshaft has a decompression device for an internal combustion engine, wherein a valve lifter is rotatably supported in a base circle of a cam, which can be brought into operative connection with a gas exchange valve via rotation. The valve lifter is operatively connected to a centrifugal fly weight, which is arranged coaxially to the camshaft and which is rotatably supported, in such a way that the valve lifter forms a contour of the base circle in the region of action with the gas exchange valve from a certain rotational speed of the camshaft. The camshaft has a cavity in the region of the centrifugal fly weight, to which cavity lubricant pressure can be applied. A radial first bore from the cavity to the centrifugal fly weight is arranged in the camshaft. A slideable element that can be displaced by the lubricant pressure is arranged in the first bore. By way of the design of the camshaft, an unstable centrifugal fly weight is stabilized and thus acoustics are improved.

Abstract: A method for operating an engine system is provided, the method may include varying a compression ratio of a cylinder by selectively releasing combustion charge from the cylinder through a cylinder bleed valve of a cylinder head, the cylinder bleed valve coupled to a bleed manifold with a turbine-generator, and varying combustion charge flow through a turbine-generator bypass conduit bypassing the turbine-generator based on engine operating conditions. In this way, the compression ratio may be varied by selectively bleeding combustion charge from the cylinder based on engine operating conditions to promote better engine performance. Additionally, the combustion charge bleed from the cylinder can routed around a turbine-generator to increase combustion efficiency during certain operating conditions, such as during start-up, to further improve engine performance.

Abstract: An engine compression brake device is disclosed. The brake device has at least one camshaft which has at least one cam group with at least one firing cam and at least one brake cam, and has at least one cam follower which is functionally assigned to the firing cam and which is provided for actuating at least one gas exchange valve in a firing mode, and has a cam follower which is functionally assigned to the brake cam and which is provided for actuating at least one gas exchange valve in a braking mode. The brake device further has a switchover device which is provided for the switchover between the firing mode and the braking mode, where the switchover device is provided for converting a torque of the camshaft into a force for the switchover between the firing mode and the braking mode.

Abstract: An internal combustion includes: a camshaft having a metal core rod insert formed centrally in the camshaft and a driven gear, an exhaust cam, etc. formed of resin integrally with the camshaft; and a decompression mechanism. The decompression mechanism includes: a pair of supporting protrusions provided on the driven gear and each having an insertion hole; a decompression member having a pair of projections disposed between the supporting protrusions; and a biasing spring disposed between the projections for normally biasing the decompression member toward the exhaust cam. The camshaft also has a guide recess and a balancing recess formed in opposite sides of the camshaft, and the metal core rod is exposed through the guide recess and the balancing recess.

Abstract: A crankshaft rotating angle controlling method and a crankshaft rotating angle controlling system are provided. A shut-off signal is obtained, and an engine speed is judged. If the engine speed is lower than a specific value, a generator is set in a driving mode at an ending point of a missing tooth signal in a gear pulse signal, such that the generator in the driving mode drives a crankshaft to exceed a top-dead-center of a cylinder. When the crankshaft arrives at a bottom-dead-center of the cylinder, the generator is set to be in a holding mode of an error phase of a three-phase current. Through the generator in the driving mode, the given error phase of the three-phase current stops the generator immediately and the crankshaft is fixed within an angle range of a default stop position.

Abstract: An air cooled V-twin engine comprises first and second cylinders, first and second cylinder heads, first and second fuel injectors, a fuel tank, and first and second fuel pumps. The cylinders and the cylinder heads comprise cooling fins and define first and second combustion chambers. Each of the fuel injectors is attached to a respective one of the cylinder heads in a manner such that they can discharge fuel directly into said combustion chamber. The first fuel pump is operatively connected to the fuel tank and to the second fuel pump in a manner such that the first fuel pump can pump fuel from the fuel tank to the second fuel pump. The second fuel pump is operatively connected to the fuel injectors in a manner such that the second fuel pump can pump fuel to the fuel injectors.

Abstract: An exhaust system is disclosed for use with an engine. The exhaust system may have a compression relief valve associated with an engine cylinder. The exhaust system may also have an exhaust gas recirculation passage extending from the compression relief valve to an intake of the engine cylinder.

Abstract: A valve operating system for an internal combustion engine, which includes a decompression cam member (47) that is supported on a camshaft (26) and that operates an exhaust valve operating member (29e) in an opening direction of an exhaust valve (17e) in a compression stroke when the engine is started, an exhaust gas recirculation cam member (48) that is supported on the camshaft (26) and that operates the exhaust valve operating member (29e) in the opening direction of the exhaust valve (17e) in an intake stroke when the engine is running at high speed, and a centrifugal mechanism (46) that is mounted on a driven timing rotating member (32) rotating integrally with the valve operating cam (25) and makes the decompression cam member (47) and the exhaust gas recirculation cam member (48) move, wherein the valve operating cam (25) is provided with a recess (39) surrounding the camshaft (26), the recess (39) opening on the face on the other side of the driven timing rotating member (32) and on a base face of the

Abstract: A controller of a variable valve apparatus of an internal combustion engine has an engine start indication detecting circuit that detects an indication of an engine start. When the indication of the engine start is detected by the engine start indication detecting circuit in a state in which temperature of the engine is lower than a predetermined temperature, an electric motor provided in the variable valve apparatus is supplied with a current, and this current supply to the electric motor is maintained for a predetermined time from a time point of the detection of the indication of the engine start to an engine cranking start.

Abstract: A system for actuating an engine valve to decompress an engine cylinder for engine start up and/or engine braking is disclosed. The system may include a first member, such as an outer piston, disposed above an engine valve, which receives an inner piston extending into a bore provided in the first member. One or more springs may bias the inner piston into a predefined position in the first member. The inner piston may include a lower surface that directly, or through an intervening sliding pin, actuates an engine valve in response to the application of fluid pressure on the inner piston. The inner piston may be used to decompress an engine cylinder for engine start up and/or to provide engine braking.

Abstract: Engine valve actuation systems and methods used to decompress an engine cylinder during engine start-up, shut-down, and for bleeder braking are disclosed. An exemplary system may include a rocker arm pivotally mounted on a rocker shaft, and a structure mounted adjacent to the rocker arm in a fixed position relative to the rocker arm. A latch piston may be slidably disposed between the rocker arm and the structure. The latch piston may be selectively extended to engage both the rocker arm and structure to limit the pivotal motion of the rocker arm and maintain the engine valves in an open condition.

Abstract: A method and apparatus for starting an internal combustion engine is disclosed. A motor is mechanically coupled to the engine, the engine having at least one moveable element mounted in a chamber, the moveable element being operable to cause a changing compression condition within the chamber and being mechanically coupled to a shaft for generating mechanical power. The method involves causing the motor to supply a positioning torque to the engine to move the at least one moveable element into a starting position, The method also involves causing the motor to supply a starting torque to the engine when the at least one moveable element is in the starting position to cause the moveable element to accelerate from the starting position under low compression conditions to generate sufficient momentum to overcome a peak compression condition in the chamber, thereby reducing the starting torque required to start the engine.

Abstract: In a method for determining, whether a crankshaft of a combustion engine rotating forward after a reverse rotation is oscillating or continues the forward movement, when noticing a reverse rotation of the crankshaft, the covered rotational angle during a reverse rotation is detected, an actual threshold is computed by adding the covered rotational angle and a predetermined safety distance. The rotational angle of the crankshaft rotating immediately forward after a reverse rotation is compared to the actual threshold.

Abstract: A hybrid powertrain includes an internal combustion engine, an electro-mechanical transmission and an electric machine. In an engine starting routine, flow control devices located proximate each combustion chamber in the engine initially restrict airflow into the cylinders to allow for a starter motor to rotate the engine at lower expansion and compression torque whereafter rotation of the engine is transitioned to the electric machine.

Abstract: A method for improving starting of an engine that may be operated with fuels having varying alcohol concentrations is presented. In one embodiment, the method adjusts a compression ratio of an engine in response to a number of combustion events after an engine stop and a concentration of alcohol in a fuel supplied to the engine. The method may make engine starting more repeatable at lower engine temperatures.

Abstract: A decompression mechanism provided in a valve operating system configured to drive a valve for opening and closing a port, includes an accommodating member provided in the valve operating system; a decompression member which is accommodated in the accommodating member such that the decompression member is extendable and retractable, the decompression member being configured to extend from the valve operating system to press the valve to open the port in a compression stroke of the engine; and an insertion member which is inserted into the valve operating system, the insertion member being configured to be inserted through the accommodating member in a direction crossing a direction in which the decompression member is extendable and retractable.

Abstract: A decompressor for an internal combustion engine that is capable of preventing the dropping-off of the decompression shaft during maintenance work includes a falling-off prevention pin inserted into a pin insertion hole having an opening to the outer circumferential surface of a camshaft and intersecting, at least partially, an insertion hole. A decompression shaft is inserted and fitted into the insertion hole. The falling-off prevention pin engages with the decompression shaft while the decompression shaft is allowed to rotate. The decompression shaft is prevented from moving in the axial direction of the decompression shaft. The opening of the pin insertion hole of the camshaft into which the falling-off prevention pin is inserted is blocked by a bearing. A swing portion includes a bearing-restriction portion formed so as to protrude towards the bearing. The bearing-restrict portion restricts the movement of the bearing in the axial direction of the camshaft.

Abstract: A method for adjusting a camshaft of an internal combustion engine during a stop phase and during a subsequent new startup phase of the internal combustion engine. Such methods are used, in particular, in so-called start-stop designs for combustion engines. The camshaft controls intake valves and/or exhaust valves of the internal combustion engine and is adjustable by a camshaft adjuster. By a desired startup position of the camshaft adjuster, control time points of the intake valves and/or the exhaust valves are defined in which mechanical work necessary for starting the internal combustion engine is reduced and/or pollutant emissions of the internal combustion engine are reduced. In the method according to the invention it is provided that the camshaft adjuster is set in a desired stop position during the stop phase. During a first section of the startup phase, the camshaft adjuster is set from the desired stop position into the desired startup position.

Abstract: To suppress the overall length of a camshaft including the length of a decompression device provided in an engine and also to suppress an increase in number of parts of the decompression device, an engine includes a decompression device having a decompression weight pivotably supported through a pivot shaft to a camshaft and adapted to be rotated at a predetermined angle by a centrifugal force generated during the rotation of the camshaft. A weight accommodating portion for pivotably accommodating the decompression weight is formed between the opposite end portions of the camshaft. The outer diameter of the decompression device mounted to the camshaft is smaller than that of a ball bearing. The decompression weight is directly engaged with one end of a decompression camshaft to thereby rotate the decompression camshaft.

Abstract: A compression release assembly is disclosed, the assembly including a camshaft rotatable about a camshaft axis, a trigger rotatable about a trigger axis substantially perpendicular to the camshaft axis, and a spring position between the trigger and the camshaft. Preferably, the trigger is rotated from an engagement position toward a disengagement position when a rotational velocity of the camshaft achieves a known value, and is rotated from the disengagement position toward the engagement position when the rotational velocity of the camshaft is below the known value.

Abstract: A compression release assembly is disclosed, the assembly including a camshaft rotatable about a camshaft axis, a trigger rotatable about a trigger axis substantially perpendicular to the camshaft axis, and a spring position between the trigger and the camshaft. Preferably, the trigger is rotated from an engagement position toward a disengagement position when a rotational velocity of the camshaft achieves a known value, and is rotated from the disengagement position toward the engagement position when the rotational velocity of the camshaft is below the known value.

Abstract: A method of operating a hybrid powertrain system is provided for a vehicle that includes an internal combustion engine having an engine output to drive the vehicle and a motor having a motor output to drive the vehicle. The motor is operatively connected to the engine and operable to crank the engine. The method includes the steps of reducing compression in at least one engine cylinder and operating the motor to crank the engine. A hybrid powertrain system for a hybrid vehicle is also provided.

Abstract: A decompression apparatus includes a plunger and a decompression shaft. The plunger is provided in a plunger hole formed in a cam shaft which is configured to move an engine valve of an internal combustion engine. The plunger is movable in the plunger hole between a decompression position in which the plunger opens the engine valve and a decompression cancel position in which the plunger does not open the engine valve. The plunger hole has a first opening which partially locates on a cam surface of a valve cam which is provided on the cam shaft. A first end portion of the plunger protrudes from the first opening to open the engine valve in the decompression position. The decompression shaft is provided in the cam shaft and configured to move the plunger between the decompression position and the decompression cancel position.

Abstract: An apparatus and method for establishing two operating compression ratios in an internal combustion engine resulting in improved mileage and including the provision of a fuel additive vapor for reducing a required temperature for compression.

Abstract: A method for adjusting a camshaft of an internal combustion engine during a stop phase and during a subsequent new startup phase of the internal combustion engine. Such methods are used, in particular, in so-called start-stop designs for combustion engines. The camshaft controls intake valves and/or exhaust valves of the internal combustion engine and is adjustable by a camshaft adjuster. By a desired startup position of the camshaft adjuster, control time points of the intake valves and/or the exhaust valves are defined in which mechanical work necessary for starting the internal combustion engine is reduced and/or pollutant emissions of the internal combustion engine are reduced. In the method according to the invention it is provided that the camshaft adjuster is set in a desired stop position during the stop phase. During a first section of the startup phase, the camshaft adjuster is set from the desired stop position into the desired startup position.

Abstract: An automatic decompression mechanism for selectively actuating a cylinder valve of an engine so as to reduce the starting force required to start the engine. The mechanism includes a cam gear, a centrifugal member, and a cover member comprising an integrally formed biasing means for biasing and retaining the centrifugal member in the cam gear. The biasing means urges the centrifugal member into a decompression position when the cam gear is rotating at a lower speed, wherein a projecting portion of the centrifugal member actuates the valve mechanism to reduce the starting force required to start the engine. During normal engine operation, the centrifugal member pivots into a non-decompression position wherein the projecting portion of the centrifugal member recedes below the cam profile surface so as to prevent the projecting portion from actuating the valve mechanism.

Abstract: An automatic decompression mechanism for selectively actuating a cylinder valve of an engine so as to reduce the starting force required to start the engine. The mechanism includes a cam gear, a centrifugal member, and a cover member comprising an integrally formed biasing means for biasing and retaining the centrifugal member in the cam gear. The biasing means urges the centrifugal member into a decompression position when the cam gear is rotating at a lower speed, wherein a projecting portion of the centrifugal member actuates the valve mechanism to reduce the starting force required to start the engine. During normal engine operation, the centrifugal member pivots into a non-decompression position wherein the projecting portion of the centrifugal member recedes below the cam profile surface so as to prevent the projecting portion from actuating the valve mechanism.

Abstract: An internal combustion engine including a valve system and a breather system. The valve system includes a camshaft having intake cams and exhaust cams. The intake cams open and close intake valves, and the exhaust cams open and close exhaust valves. The breather system includes an upstream-side breather chamber and a downstream-side breather chamber. Blow-by gas flows into the upstream-side breather chamber through a chain chamber. The down-stream side breather chamber is provided in the camshaft, and also formed of a through hole constituted of a plurality of hole portions. The hole portions have different sizes and are aligned in the axial direction. The through bole opens to the chain chamber at a first shaft end portion of the camshaft, and also opens to the down-stream side breather chamber at a second shaft end portion of the camshaft. The down-stream side breather chamber is formed of a cam holder.

Abstract: An internal combustion engine (101, 601, 901) alters an effective compression ratio from an effective compression ratio for a start-up operation to a larger effective compression ratio for a normal operation when an engine rotation speed (NE) increases beyond a resonance rotation speed region during cranking. A controller (104, 610, 910) determines whether or not the engine (101, 601, 901) has reached a combustion possible state on the basis of the engine rotation speed (NE) during cranking and an operating parameter (PA, TA, TW, P_Rail, V_Ang) other than the engine rotation speed (NE) (S1102, S1202, S1204). When the determination is negative, the controller (104, 610, 910) inhibits fuel supply to the engine (101, 601, 901) by a fuel supply device (207), even when the engine rotation speed has increased beyond the resonance rotation speed region (S406). In so doing, a combustion defect such as a misfire is prevented.

Abstract: To suppress the overall length of a camshaft including the length of a decompression device provided in an engine and also to suppress an increase in number of parts of the decompression device, an engine includes a decompression device having a decompression weight pivotably supported through a pivot shaft to a camshaft and adapted to be rotated at a predetermined angle by a centrifugal force generated during the rotation of the camshaft. A weight accommodating portion for pivotably accommodating the decompression weight is formed between the opposite end portions of the camshaft. The outer diameter of the decompression device mounted to the camshaft is smaller than that of a ball bearing. The decompression weight is directly engaged with one end of a decompression camshaft to thereby rotate the decompression camshaft.

Abstract: Mechanical compression and vacuum release mechanisms for internal combustion engines. The compression and vacuum release mechanism may include a pair of centrifugally responsive flyweights pivotally mounted to the cam gear. One of the flyweights actuates a vacuum release member having a vacuum release cam and the other of the flyweights actuates a compression release member having a compression release cam. In another embodiment, the compression and vacuum release mechanism includes a single flyweight having structure associated therewith to actuate a vacuum release member and a compression release member having respective vacuum and compression release cams. The compression and vacuum release cams are in lifting engagement with the valve actuation structure of one of the intake or exhaust valves of the engine during engine starting to relieve compression and vacuum within the combustion chamber and thereby facilitate easier engine starting.

Abstract: At an intake timing of an initial combustion cylinder, an actual intake valve timing is adjusted to a target intake valve timing corresponding to a target intake air flow rate of the initial combustion cylinder. At intake timing of the other cylinders which contributes to increment of the engine speed after the initial combustion, the actual intake valve timing is adjusted to a target valve timing corresponding to a target intake air flow rate of the other cylinders. Thereby, the intake air flow rate of each cylinder is accurately controlled, so that the increment of the engine speed is restricted within a range in which a startability is not deteriorated and a vehicle vibration and an over shoot of the engine speed is appropriately restricted.

Abstract: An internal combustion engine (101, 601, 901) alters an effective compression ratio from an effective compression ratio for a start-up operation to a larger effective compression ratio for a normal operation when an engine rotation speed (NE) increases beyond a resonance rotation speed region during cranking. A controller (104, 610, 910) determines whether or not the engine (101, 601, 901) has reached a combustion possible state on the basis of the engine rotation speed (NE) during cranking and an operating parameter (PA, TA, TW, P_Rail, V_Ang) other than the engine rotation speed (NE) (S1102, S1202, S1204). When the determination is negative, the controller (104, 610, 910) inhibits fuel supply to the engine (101, 601, 901) by a fuel supply device (207), even when the engine rotation speed has increased beyond the resonance rotation speed region (S406). In so doing, a combustion defect such as a misfire is prevented.

Abstract: A pull-starter for a combustion engine of an engine-powered apparatus having a startup element automatically actuated upon initial pulling of a pull-cord. The pull-cord is attached to and wound around a recoil pulley, routed at least partially around a portion of a movable dampener member, and attached to a handle. The dampener member is biased toward a rest position and a portion thereof is linked to the startup element. The pull-cord is pulled to displace the dampener member away from its rest position, automatically actuate the at least one startup element, and unwind the pull-cord from around the recoil pulley and thereby rotate the recoil pulley in an unwind direction to rotate a crankshaft of the engine via a coupling. At least upon release of the pull-cord, the dampener member and the startup element automatically return to their normal state during engine operation.

Abstract: An engine decompression system that can secure a projecting height of a decompression cam from a base face of a valve operating cam to be relatively large in an engine starting rotational region, and maintain a state in which the projection height is decreased in a complete combustion rotational region of the engine. The decompression system includes a decompression cam shaft provided on a valve operating cam shaft or a rotating member integrally coupled thereto, the decompression cam shaft being capable of rotating between an operating position in which a decompression cam projects above a base face of a valve operating cam to slightly open engine valves during a compression stroke and a release position in which the decompression cam is withdrawn to allow the engine valves to close.

Abstract: An engine decompressor includes a decompressor pin provided through a pin hole on the surface of a valve cam, a decompressor pin operating shaft in an oil passage provided in a valve cam shaft of the valve cam for vertically moving the decompressor pin by its rotation, a fly weight rotatable by rotation of the valve cam shaft so as to rotate the decompressor pin operating shaft, and a thrust receiving plate separate from the fly weight for restricting the axial movement of the decompressor pin operating shaft in the oil passage. The engine decompressor is capable of operating a decompressor mechanism normally even if the lubricating oil increases in pressure.

Abstract: Satisfactory restartability has not been obtained so far because the timing of opening an exhaust valve of a cylinder under expansion stroke is adjusted for improvement of startability and a valve adjusting mechanism is always controlled in the same manner regardless of the engine status at start. In the invention, control is performed to adjust the timing of closing an intake valve so that an effective compression ratio of a cylinder under compression stroke reduces. Also, the effective compression ratio of the compression stroke cylinder is decided based on a piston position at engine restart. By varying the intake valve closing timing in the expansion stroke cylinder to reduce the effective compression ratio depending on the engine status at restart, it is possible to lessen a load imposed on a starter when the engine is restarted, and to improve startability without complicating the engine system.

Abstract: An engine features a decompression mechanism that extends through a bore formed in a camshaft. The mechanism has an actuator that is formed of multiple shafts. The shafts are joined in the region of a decompression pin. The actuator rotates relative to the camshaft and the rotation drives translation of decompression pins in a radial direction of the camshaft.

Abstract: The description relates to a method for starting a direct-injection internal combustion engine equipped with an engine management system and having n cylinders, in which n pistons oscillate between a top dead center (TDC) and a bottom dead center (BDC), and a crankshaft. It is proposed to set forth a method of the aforesaid type which overcomes the known disadvantages inherent in the state of the art known, the particular intention being to achieve a shortening of the starting times.

Abstract: Mechanical compression and vacuum release mechanisms which are of simple construction and which significantly reduce the effort required to start an internal combustion engine. In several embodiments, the compression and vacuum release mechanisms include a centrifugally responsive flyweight pivotally mounted to the camshaft, the flyweight coupled to a pair of compression and vacuum release pins which include respective compression and vacuum release cams that are in lifting engagement with the valve actuation structure of one of the intake or exhaust valves of the engine during engine starting to relieve compression and vacuum within the combustion chamber and thereby facilitate easier engine starting. After the engine is started and reaches running speed, the flyweight pivots responsive to centrifugal force and in turn pivots the compression and vacuum release cams out of engagement with the valve actuation structure of the intake or exhaust valve to allow the engine to operate normally.