Abstract: A rope reel includes first circumferential wall portion that is erectly provided so as to surround outer circumference of recoil spring. A starter case includes second circumferential wall portion that is erectly provided so as to adjoin inner circumferential face or outer circumferential face of first circumferential wall portion. The first circumferential wall portion and the second circumferential wall portion are disposed so that end edges of the first circumferential wall portion and the second circumferential wall portion overlap each other when viewed in radial direction. A plate is disposed between starter case and recoil spring inside first circumferential wall portion. Thus, it is possible to provide structure which is realized in space-saving manner to make foreign substances difficult to intrude into starting device in order to prevent deformation or damage of recoil spring, and from which the foreign substances are easily discharged even if foreign substances have intruded.

Abstract: A rope reel includes first circumferential wall portion that is erectly provided so as to surround outer circumference of recoil spring. A starter case includes second circumferential wall portion that is erectly provided so as to adjoin inner circumferential face or outer circumferential face of first circumferential wall portion. The first circumferential wall portion and the second circumferential wall portion are disposed so that end edges of the first circumferential wall portion and the second circumferential wall portion overlap each other when viewed in radial direction. A plate is disposed between starter case and recoil spring inside first circumferential wall portion. Thus, it is possible to provide structure which is realized in space-saving manner to make foreign substances difficult to intrude into starting device in order to prevent deformation or damage of recoil spring, and from which the foreign substances are easily discharged even if foreign substances have intruded.

Abstract: The device includes an exhaust passage having an upstream end connected to an exhaust port of the engine and a downstream end provided with a catalytic converter, a secondary air passage having a downstream end connected to an intermediate point of the exhaust passage and an upstream end communicating with the atmosphere, and a reed valve provided in an upstream end of the secondary air passage to permit air flow from the atmosphere to the exhaust passage but not in the opposite direction. The reed valve has a resonance frequency which is z times the prescribed exhaust frequency of the engine, where z is an integer. The length of the secondary air passage is selected that the pulsation effect of air in the secondary air passage may be advantageously utilized.

Abstract: In a control apparatus for a general-purpose internal combustion engine including a generator as a power supply, the generator includes a main generator coil supplying power to the stepping motor, and an auxiliary generator coil supplying power to an ignition device of the engine. The apparatus includes ignition timing controller for, when starting the engine by a manual starter, detecting that an engine speed reaches or exceeds a predetermined engine speed not exceeding a connecting rotation speed of a centrifugal clutch to retard an ignition timing of the engine, thereby suppressing increase in the engine speed to less than the connecting rotation speed, and for restoring the ignition timing to its normal timing after a predetermined time elapses from start of retarding the ignition timing. Accordingly, it suppresses overshooting of an engine speed above the connecting rotation speed even if a delay occurs in closing a throttle valve by a delay in activating the motor.

Abstract: The device includes an exhaust passage having an upstream end connected to an exhaust port of the engine and a downstream end provided with a catalytic converter, a secondary air passage having a downstream end connected to an intermediate point of the exhaust passage and an upstream end communicating with the atmosphere, and a reed valve provided in an upstream end of the secondary air passage to permit air flow from the atmosphere to the exhaust passage but not in the opposite direction. The reed valve has a resonance frequency which is z times the prescribed exhaust frequency of the engine, where z is an integer. The length of the secondary air passage is selected that the pulsation effect of air in the secondary air passage may be advantageously utilized.

Abstract: In a control apparatus for a general-purpose internal combustion engine including a generator as a power supply, the generator includes a main generator coil supplying power to the stepping motor, and an auxiliary generator coil supplying power to an ignition device of the engine. The apparatus includes ignition timing controller for, when starting the engine by a manual starter, detecting that an engine speed reaches or exceeds a predetermined engine speed not exceeding a connecting rotation speed of a centrifugal clutch to retard an ignition timing of the engine, thereby suppressing increase in the engine speed to less than the connecting rotation speed, and for restoring the ignition timing to its normal timing after a predetermined time elapses from start of retarding the ignition timing. Accordingly, it suppresses overshooting of an engine speed above the connecting rotation speed even if a delay occurs in closing a throttle valve by a delay in activating the motor.

Abstract: A vertical engine includes: an oil pump provided adjacent to the lower surface of a cylinder barrel and connected to a lower end portion of a cam gear shaft to be driven by the gear shaft; a first lubricating oil passageway for supplying lubricating oil from the oil pump to a lower bearing of a crankshaft; a second lubricating oil passageway extending through the crankshaft from the lower bearing to an upper bearing of the crankshaft; a third lubricating oil passageway provided adjacent to the upper surface of the barrel and extending from the crankcase to immediately below stem end portions of intake and exhaust valves so that lubricating oil leaked from the second lubricating oil passageway flows therethrough; and a fourth lubricating oil passageway for returning lubricating oil, dripped down from the third lubricating oil passageway to the stem end portions, to the pump.

Abstract: A vertical engine includes: an oil pump provided adjacent to the lower surface of a cylinder barrel and connected to a lower end portion of a cam gear shaft to be driven by the gear shaft; a first lubricating oil passageway for supplying lubricating oil from the oil pump to a lower bearing of a crankshaft; a second lubricating oil passageway extending through the crankshaft from the lower bearing to an upper bearing of the crankshaft; a third lubricating oil passageway provided adjacent to the upper surface of the barrel and extending from the crankcase to immediately below stem end portions of intake and exhaust valves so that lubricating oil leaked from the second lubricating oil passageway flows therethrough; and a fourth lubricating oil passageway for returning lubricating oil, dripped down from the third lubricating oil passageway to the stem end portions, to the pump.

Abstract: A thermal demand priority type cogeneration system, is made operative for obtaining power output without thermal demand. When the temperature in a hot water tank 17 is low, a heat request is output from a heat request generator 42 and thereby an engine 11 is driven. When the temperature T higher than a predetermined temperature T1, a first water supply instructing unit 44 opens a valve 39 and supplies water to the tank 17 to decrease the water temperature T. When the water temperature goes down, thermal demand is generated, the engine 11 is driven according to the heat request. So as to generate thermal demand, a discharge valve 41 may be opened when the water temperature T is at the predetermined temperature or higher. A second water supply instructing unit 46 opens the valve 39 when reserved water level in the tank 17 goes down. When the valve 39 is opened, water is supplied and the water temperature goes down and thermal demand is generated.

Abstract: In a general-purpose engine having a throttle valve installed in an air intake passage connected to a combustion chamber, sucked air mixing with fuel to generate an air-fuel mixture to be ignited to drive a piston to rotate a crankshaft connected to a load, a first warm-up time period during which the engine is warmed up and a second warm-up time period which is longer than the first time period are determined based on detected engine temperature and a fuel quantity is increased during the first time period. The operation of the motor is controlled such that a change rate of throttle valve opening is limited within a range until the measured time exceeds the second warm-up time period after it exceeded the first time period. With this, it becomes possible to complete warm-up operation in a short period of time, while improving rate of fuel consumption and emission performance.

Abstract: In a general-purpose internal combustion engine having a throttle valve and a choke valve each installed in an air intake passage connected to a combustion chamber, air sucked in flowing through the air intake passage and mixing with fuel supplied by a carburetor to generate an air-fuel mixture that enters the combustion chamber of a cylinder and is ignited to drive a piston to rotate a crankshaft to be connected to a load such as a generator, there are provided an electric motor (actuator), a throttle valve opening/closing mechanism connected to the motor to open/close the throttle valve and a choke valve opening/closing mechanism connected to the throttle valve opening/closing mechanism to open/close the choke valve in response to operation of the throttle valve opening/closing mechanism, thereby enabling to move a choke valve without need to install an additional actuator.

Abstract: In a capacitor-discharge ignition system for an internal combustion engine having a power generation coil, a capacitor connected to the power generation coil, an ignition coil having a primary winding connected to the capacitor through a thyristor and a secondary winding connected to a spark plug, and a microprocessor which turns on the thyristor at a predetermined crank angular position to produce ignition in the spark plug, an engine stop switch is installed to input an engine-stop command signal to the microprocessor when being turned off by the operator. With this, it becomes possible to surely stop the engine at any time if desired.

Abstract: In a general-purpose internal combustion engine having a throttle valve and a choke valve each installed in an air intake passage connected to a combustion chamber, air sucked in flowing through the air intake passage and mixing with fuel supplied by a carburetor to generate an air-fuel mixture that enters the combustion chamber of a cylinder and is ignited to drive a piston to rotate a crankshaft to be connected to a load such as a generator, there are provided an electric motor (actuator), a throttle valve opening/closing mechanism connected to the motor to open/close the throttle valve and a choke valve opening/closing mechanism connected to the throttle valve opening/closing mechanism to open/close the choke valve in response to operation of the throttle valve opening/closing mechanism, thereby enabling to move a choke valve without need to install an additional actuator.

Abstract: In a general-purpose engine having a throttle valve installed in an air intake passage connected to a combustion chamber, sucked air mixing with fuel to generate an air-fuel mixture to be ignited to drive a piston to rotate a crankshaft connected to a load, a first warm-up time period during which the engine is warmed up and a second warm-up time period which is longer than the first time period are determined based on detected engine temperature and a fuel quantity is increased during the first time period. The operation of the motor is controlled such that a change rate of throttle valve opening is limited within a range until the measured time exceeds the second warm-up time period after it exceeded the first time period. With this, it becomes possible to complete warm-up operation in a short period of time, while improving rate of fuel consumption and emission performance.

Abstract: In a capacitor-discharge ignition system for an internal combustion engine having a power generation coil, a capacitor connected to the power generation coil, an ignition coil having a primary winding connected to the capacitor through a thyristor and a secondary winding connected to a spark plug, and a microprocessor which turns on the thyristor at a predetermined crank angular position to produce ignition in the spark plug, an engine stop switch is installed to input an engine-stop command signal to the microprocessor when being turned off by the operator. With this, it becomes possible to surely stop the engine at any time if desired.

Abstract: A thermal demand priority type cogeneration system, is made operative for obtaining power output without thermal demand. When the temperature in a hot water tank 17 is low, a heat request is output from a heat request generator 42 and thereby an engine 11 is driven. When the temperature T higher than a predetermined temperature T1, a first water supply instructing unit 44 opens a valve 39 and supplies water to the tank 17 to decrease the water temperature T. When the water temperature goes down, thermal demand is generated, the engine 11 is driven according to the heat request. So as to generate thermal demand, a discharge valve 41 may be opened when the water temperature T is at the predetermined temperature or higher. A second water supply instructing unit 46 opens the valve 39 when reserved water level in the tank 17 goes down. When the valve 39 is opened, water is supplied and the water temperature goes down and thermal demand is generated.

Abstract: In an exhaust emission control system for an engine, comprising an exhaust emission control catalyst disposed in an exhaust muffler whose inside is divided into a plurality of chambers, at least a portion of the inside of the exhaust muffler is divided into a first chamber for converting mainly NOx in exhaust gas and a second chamber for converting HC and CO in the exhaust gas. The exhaust muffler comprises: a partition wall having a conduit for guiding the exhaust gas from the first chamber to the second chamber; an exhaust gas inlet for introducing the exhaust gas into the first chamber; an external-air suction means for sucking external air into the second chamber; and a discharge pipe for discharging the external air and the exhaust gas flowing through the second chamber.

Abstract: An exhaust gas reflux apparatus for an internal combustion engine includes one-way connection means provided between an intake rocker arm and an exhaust rocker arm. The one-way connection means moves between a non-operating position where the intake and exhaust rocker arms are released and an operating position where the intake and exhaust rocker arms are connected to open the exhaust valve only when the intake rocker arm rocks in a valve opening direction of the intake valve. An actuator for switching the one-way connection means between the non-operating position and the operating position is connected to the one-way connection means. Thus, an exhaust gas is sucked into a combustion chamber from an exhaust port using a general exhaust valve in an intake stroke, when exhaust gas reflux is required.

Abstract: An exhaust gas reflux apparatus for an internal combustion engine includes one-way connection means provided between an intake rocker arm and an exhaust rocker arm. The one-way connection means moves between a non-operating position where the intake and exhaust rocker arms are released and an operating position where the intake and exhaust rocker arms are connected to open the exhaust valve only when the intake rocker arm rocks in a valve opening direction of the intake valve. An actuator for switching the one-way connection means between the non-operating position and the operating position is connected to the one-way connection means. Thus, an exhaust gas is sucked into a combustion chamber from an exhaust port using a general exhaust valve in an intake stroke, when exhaust gas reflux is required.

Abstract: In an exhaust emission control system for an engine, comprising an exhaust emission control catalyst disposed in an exhaust muffler whose inside is divided into a plurality of chambers, at least a portion of the inside of the exhaust muffler is divided into a first chamber for converting mainly NOx in exhaust gas and a second chamber for converting HC and CO in the exhaust gas. The exhaust muffler comprises: a partition wall having a conduit for guiding the exhaust gas from the first chamber to the second chamber; an exhaust gas inlet for introducing the exhaust gas into the first chamber; an external-air suction means for sucking external air into the second chamber; and a discharge pipe for discharging the external air and the exhaust gas flowing through the second chamber.